Introduction to Psychology
A Research Paper Presented to
The Academic Department of the
School of Social and Human Studies
In Partial Fulfillment of the Academic Requirements
For the Degree of PhD in Psychology
Atlantic International University
Table of Contents
Table contents ---------------------------------------------------------------------------- 2
Introduction ------------------------------------------------------------------------------ 3-4
Psychology definition s------------------------------------------------------------------ 4-7
Human development -------------------------------------------------------------------- 8-13
Evolution by means of natural selection --------------------------------------------- 13-23
The nature-nurture controversy ------------------------------------------------------- 24-26
Structure and function of the brain --------------------------------------------------- 26-27
Sensation and Perception -------------------------------------------------------------- 27-35 Development, Personality, and Stage theory --------------------------------------- 36-48
Mind body Connection ---------------------------------------------------------------- 48-52
Learning theory and behavioral Psychology --------------------------------------- 52-57 Memory, Intelligence, and states of mind ------------------------------------------ 57-86
Motivation and Emotion -------------------------------------------------------------- 86-96
Branches of Psychology -------------------------------------------------------------- 96-111 Research methods in Psychology --------------------------------------------------- 111-118
Criticism ------------------------------------------------------------------------------- 118-119
We all use the principles of psychology everyday and probably don’t even realize it. When we spank our child for doing something wrong, we are utilizing the learning principle of punishment. When we get nervous right before we have to give that big speech, we are activating our autonomic nervous system. When we talk to ourselves in our heads, telling ourselves to "calm down," "work harder," or "give up," we are utilizing cognitive approaches to change our behaviors and emotions.
1.1.0. In essence, Psychology is the study of cognitions, emotions, and behavior. Psychologists are involved in a variety of tasks. Many spend their careers designing and performing research to better understand how people behave in specific situations, how and why we think the way we do, and how emotions develop and what impact they have on our interactions with others. These are the research psychologists who often work in research organizations or universities. Industrial-organizational psychologists work with businesses and organizations to help them become more productive, effective, and efficient, and to assist them in working with their employees and their customers. Practitioners, typically counseling and clinical psychologists, work with individuals, couples, families, and small groups to help them feel less depressed, less anxious, become more productive or motivated, and overcome issues which prevent them from living up to their potentials.
1. 1. 1. Psychology differs from the other social sciences anthropology, economics, political science, and sociology in seeking to explain the mental processes and behavior of individuals. Psychology differs from biology and neuroscience in that it is primarily concerned with the interaction of mental processes and behavior on a systemic level, as opposed to studying the biological or neural processes themselves. In contrast, the subfield of neuropsychology studies the actual neural processes and how they relate to the mental effects they subjectively produce. Biological psychology is the scientific study of the biological bases of behavior and mental states.
2.0. The study of Psychology has five goals:
1. Describe – The first goal is to observe behavior and describe, often in minute detail, what was observed as objectively as possible
2. Explain – While descriptions come from observable data, psychologists must go beyond what is obvious and explain their observations. In other words, why did the subject do what he or she did?
3. Predict – Once we know what happens, and why it happens, we can begin to speculate what will happen in the future. There’s an old saying, which very often holds true: "the best predictor of future behavior is past behavior."
4. Control – Once we know what happens, why it happens and what is likely to happen in the future, we can excerpt control over it. In other words, if we know you choose abusive partners because your father was abusive, we can assume you will choose another abusive partner, and can therefore intervene to change this negative behavior.
5. Improve – Not only do psychologists attempt to control behavior, they want to do so in a positive manner, they want to improve a person’s life, not make it worse. This is not always the case, but it should always be the intention.
2. 1. 0. Various definitions of Psychology
2. 1. 1. Psychology is an academic and applied discipline involving the scientific study of mental processes and behavior. Psychology also refers to the application of such knowledge to various spheres of human activity, including relating to individuals' daily lives and the treatment of mental illness.
2.1.2. Psychology is an academic and applied field involving the study of behavior, mind and thought and the subconscious neurological bases of behavior.
2.1.3. Psychology also refers to the application of such knowledge to various spheres of human activity, including problems of individuals' daily lives and the treatment of mental illness. It is largely concerned with humans, although the behavior and mental processes of animals can also be part of psychology research, either as a subject in its own right (e.g. animal cognition and ethnology), or somewhat more controversially, as a way of gaining an insight into human psychology by means of comparison (including comparative psychology).
2.1.4. Psychology is commonly defined as the science of behavior and mental processes.
2.1.5. Psychology does not necessarily refer to the brain or nervous system and can be framed purely in terms of phenomenological or information processing theories of mind. Increasingly, though, an understanding of brain function is being included in psychological theory and practice, particularly in areas such as artificial intelligence, neuropsychology, and cognitive neuroscience.
2.1.6. Psychology describes and attempts to explain consciousness, behavior and social interaction. Empirical psychology is primarily devoted to describing human experience and behavior as it actually occurs. In the past 20 years or so psychology has begun to examine the relationship between consciousness and the brain or nervous system. It is still not clear in what ways these interact: does consciousness determine brain states or do brain states determine consciousness - or are both going on in various ways? Perhaps to understand this you need to know the definition of "consciousness" and "brain state" - or is consciousness some sort of complicated 'illusion' which bears no direct relationship to neural processes? The late 19th century marks the start of psychology as a scientific enterprise. The year 1879 is commonly seen as the start of psychology as an independent field of study, because in that year German scientist Wilhelm Wundt founded the first laboratory dedicated exclusively to psychological research in Leipzig, Germany. Wundt combined philosophical introspection with techniques and laboratory apparatuses brought over from his physiological studies with Helmholtz, as well as many of his own design. This experimental introspection was in contrast to what had been called psychology until then, a branch of philosophy where people introspected themselves.
2.1.7. Introspection is the direct observation or rumination of one's own heart, mind and/or soul and its processes, as opposed to introspection, the observation of things external to one's self.
3.0. Early Systems of Psychology
Wundt's form of psychology is called structuralism. It is in a class called systematic interpretations because it attempted to explain all behavior with reference to one systematic position. Some other systems of psychology are functionalism, behaviorism, gestalt psychology, and psychodynamic psychology.
3.1.Functionalism is concerned with the reason for behavior and not the structure of the brain. It allowed the study of new subjects including children and animals.
3.2.Behaviorism is an approach to psychology based on the proposition that behavior can be studied and explained scientifically without recourse to internal mental states. Psychologists that use behaviorism are concerned mainly with muscular movements and glandular secretions.
3.3.Gestalt psychology is a theory of mind and brain that proposes that the operational principle of the brain is holistic, parallel, and analog, with self-organizing tendencies. It has a particular interest in perceptual problems and how they can be interpereted. A Gestaltist believes that the whole is greater than or different than the sum of all of the parts. Trying to break up behavior into separate parts is simplistic because everything affects everything else.
While the use of one system to solve all problems has been abandoned by most psychologists, these early systems were important in the development of new systems and ideas. There are eight major perspectives that psychologists usually take, although many use an eclectic approach instead of confining themselves to just one.
4.1.The psychodynamic perspective emphasizes unconscious drives and the resolution of conflicts, the behavioral emphasizes the acquisition and alteration of observable responses, and the humanistic approaches attempt to achieve maximum human potential as set in Maslow's hierchy of needs.
4.2. The biological perspective is the scientific study of the biological bases of behavior and mental states, very closely related to neuroscience.
4.3. Evolutionary psychology is a theoretical approach to psychology that attempts to explain certain mental and psychological traits—such as memory, perception, or language as evolved adaptations, i.e., as the functional products of natural or sexual selection.
4.4. Cognitive psychology accepts the use of the scientific method, but rejects introspection as a valid method of investigation. It should be noted that Herbert Simon and Allen Newell identified the 'thinking-aloud' protocol, in which investigators view a subject engaged in introspection, and who speaks his thoughts aloud, thus allowing study of his introspection.
4.5. Social psychology is the scientific study of how people's thoughts, feelings, and behaviors are influenced by the actual, imagined, or implied presence of others (Allport, 1985). Wundt argued that "we learn little about our minds from casual, haphazard self-observation. It is essential that observations be made by trained observers under carefully specified conditions for the purpose of answering a well-defined question." Many scientists threw away the idea of introspection as part of psychology because the observation of stimulation was speculative without an empirical approach. However the case, an opposite to introspection called extrospection has been created with a relation to Psychophysics.
4.6.Psychophysics is the branch of psychology dealing with the relationship between physical stimuli and their perception. The important distinction is that Wundt took this method into the experimental arena and thus into the newly formed psychological field. Other important early contributors to the field of psychology include Hermann Ebbinghaus (a pioneer in studies on memory), the Russian Ivan Pavlov (who discovered the learning process of classical conditioning), and the Austrian Sigmund Freud. The mid-20th century saw a rejection of Freud's theories among many psychologists as being too unscientific, as well as a reaction against Edward Titchener's abstract approach to the mind.
5.0. Early development
5.1. The first use of the term "psychology" is often attributed to the German scholastic philosopher Rudolf Goeckel (Latinized Rudolph Goclenius), published in 1590. More than six decades earlier, however, the Croatian humanist Marko Marulić used the term in the title of a work, which was subsequently lost. This, of course, may not have been the very first usage, but it is the earliest documented use at present.
The term did not fall into popular usage until the German idealist philosopher, Christian Wolff (1679-1754) used it in his Psychologia empirical and Psychologia rationalis.This distinction between empirical and rational psychology was picked up in Diderot's Encyclopedie and was popularized in France by Maine de Biran.
The root of the word psychology (psyche) is very roughly equivalent to "soul" in Greek, and (logy) equivalent to "study". Psychology came to be considered a study of the soul (in a religious sense of this term) much later, in Christian times. Psychology as a medical discipline can be seen in Thomas Willis' reference to psychology (the "Doctrine of the Soul") in terms of brain function, as part of his 1672 anatomical treatise "De Anima Brutorum" ("Two Discourses on the Souls of Brutes"). Until about the end of the 19th century, psychology was regarded as a branch of philosophy.
6.0. Human Development
6.1. Biological basis of behavior
Like every other aspect of life, behavior is determined largely by an individual's DNA makeup. DNA can be considered as a "blueprint" for every aspect of life. Evolutionary psychologists study the role of natural selection in the passing on of behavioral and other psychological traits. Genetic makeup is generally believed to account for much of an individual's temperament.
6.2. Structure and Function of DNA
The nucleic acids are the largest of the organic molecules. DNA stands for deoxyribonucleic acid. It is made up of units called nucleotides, which themselves are composed of a deoxyribose 5-carbon sugar molecule, a nitrogen base, and a phosphate group. These nucleotides are bonded in columns by phosphate covalent bonds (very strong), and are laterally bound to other nucleotides with weaker hydrogen bonds. Nucleotides are arranged such that they form genes, which are specific biochemical units that code for a characteristic. In DNA replication, DNA is split and transcribed to form proteins, which are the basic structural units of life. Individual-to-individual variance, introduced in reproduction and meiosis, is the basis for different personality traits and differences in temperament between individuals.
7.0. Natural Selection in Behavioral Traits
7.1.Natural selection is the processes by which heritable traits that make it more likely for an organism to survive and successfully reproduce become more common in a population over successive generations. It is a key mechanism of evolution.
The natural genetic variation within a population of organisms means that some individuals will survive and reproduce more successfully than others in their current environment. For example, the peppered moth exists in both light and dark colors in the United Kingdom, but during the industrial revolution many of the trees on which the moths rested became blackened by soot, giving the dark-colored moths an advantage in hiding from predators. This gave dark-colored moths a better chance of surviving to produce dark-colored offspring, and in just a few generations the majority of the moths were dark. Factors which affect reproductive success are also important, an issue which Charles Darwin developed in his ideas on sexual selection.
Natural selection acts on the phenotype, or the observable characteristics of an organism, but the genetic (heritable) basis of any phenotype which gives a reproductive advantage will increase in frequency over the following generations (see allele frequency). Over time, this process can result in adaptations that specialize organisms for particular ecological niches and may eventually result in the emergence of new species. In other words, natural selection is an important process (though not the only process) by which evolution takes place within a population of organisms.
Natural selection is one of the cornerstones of modern biology. The term was introduced by Darwin in his groundbreaking 1859 book On the Origin of Species in which natural selection was described by analogy to artificial selection, a process by which animals and plants with traits considered desirable by human breeders are systematically favored for reproduction. The concept of natural selection was originally developed in the absence of a valid theory of heredity; at the time of Darwin's writing, nothing was known of modern genetics. The union of traditional Darwinian evolution with subsequent discoveries in classical and molecular genetics is termed the modern evolutionary synthesis. Natural selection remains the primary explanation for adaptive evolution.
7.2. General principles
Darwin's illustrations of beak variation in the finches of the Galápagos Islands, which hold 13 closely related species that differ most markedly in the shape of their beaks. The beak of each species is suited to its preferred food, suggesting that beak shapes evolved by natural selection.
Natural variation occurs among the individuals of any population of organisms. Many of these differences do not affect survival (such as differences in eye color in humans), but some differences may improve the chances of survival of a particular individual. A rabbit that runs faster than others may be more likely to escape from predators, and algae that are more efficient at extracting energy from sunlight will grow faster. Individuals that have better odds for survival also have better odds for reproduction. If the traits that give these individuals a reproductive advantage are also heritable, that is, passed from parent to child, then there will be a slightly higher proportion of fast rabbits or efficient algae in the next generation. This is known as differential reproduction. Even if the reproductive advantage is very slight, over many generations any heritable advantage will become dominant in the population, due to exponential growth. In this way the natural environment of an organism "selects" for traits that confer a reproductive advantage, causing gradual changes or evolution of life. This effect was first described and named by Charles Darwin.
The concept of natural selection predates the understanding of genetics, which is the study of heredity. In modern times, it is understood that selection acts on an organism's phenotype, or observable characteristics, but it is the organism's genetic make-up or genotype that is inherited. The phenotype is the result of the genotype and the environment in which the organism lives (see Genotype-phenotype distinction). This is the link between natural selection and genetics, as described in the modern evolutionary synthesis. Although a complete theory of evolution also requires an account of how genetic variation arises in the first place (such as by mutation and sexual reproduction) and includes other evolutionary mechanisms (such as gene flow), natural selection is still understood as a fundamental mechanism for evolution.
7.3.0.The term natural selection has slightly different definitions in different contexts. It is most often defined to operate on heritable traits, because these are the traits that directly participate in evolution. However, natural selection is "blind" in the sense that changes in phenotype (physical and behavioral characteristics) can give a reproductive advantage regardless of whether or not the trait is heritable (non heritable traits can be the result of environmental factors or the life experience of the organism).
7.3.1. Following Darwin's primary usage the term is often used to refer to both the evolutionary consequence of blind selection and to its mechanisms It is sometimes helpful to explicitly distinguish between selection's mechanisms and its effects; when this distinction is important, scientists define "natural selection" specifically as "those mechanisms that contribute to the selection of individuals that reproduce", without regard to whether the basis of the selection is heritable. This is sometimes referred to as "phenotypic natural selection".Traits that cause greater reproductive success of an organism are said to be selected for, whereas those that reduce success are selected against. Selection for a trait may also result in the selection of other correlated traits that do not themselves directly influence reproductive advantage. This may occur as a result of pleiotropy or gene linkage.
8.0.Types of selection
8.1.Natural selection can act on any phenotypic trait, and selective pressure can be produced by any aspect of the environment, including sexual selection and competition with members of the same species. However, this does not imply that natural selection is always directional and results in adaptive evolution; natural selection often results in the maintenance of the status quo by eliminating less fit variants. The unit of selection can be the individual or it can be another level within the hierarchy of biological organization, such as genes, cells, and kin groups. There is still debate about whether natural selection acts at the level of groups or species to produce adaptations that benefit a larger, non-kin group. Selection at a different level such as the gene can result in an increase in fitness for that gene, while at the same time reducing the fitness of the individuals carrying that gene, in a process called intragenomic conflict. Overall, the combined effect of all selection pressures at various levels determines the overall fitness of an individual, and hence the outcome of natural selection. The life cycle of a sexually reproducing organism. Various components of natural selection are indicated for each life stage. Natural selection occurs at every life stage of an individual. An individual organism must survive until adulthood before it can reproduce, and selection of those that reach this stage is called viability selection. In many species, adults must compete with each other for mates via sexual selection, and success in this competition determines who will parent the next generation. When individuals can reproduce more than once, a longer survival in the reproductive phase increases the number of offspring, called survival selection. The fecundity of both females and males (for example, giant sperm in certain species of Drosophila can be limited via "fecundity selection". The viability of produced gametes can differ, while intragenomic conflicts such as meiotic drive between the haploid gametes can result in gametic or "genic selection". Finally, the union of some combinations of eggs and sperm might be more compatible than others; this is termed compatibility selection.
It is useful to distinguish between "ecological selection" and "sexual selection". Ecological selection covers any mechanism of selection as a result of the environment (including relatives, e.g. kin selection, competition, and infanticide), while "sexual selection" refers specifically to competition for mates. Sexual selection can be intersexual, as in cases of competition among individuals of the same sex in a population, or intersexual, as in cases where one sex controls reproductive access by choosing among a population of available mates. Most commonly, intersexual selection involves male–male competition and intersexual selection involves female choice of suitable males, due to the generally greater investment of resources for a female than a male in a single offspring. However, some species exhibit sex-role reversed behavior in which it is males that are most selective in mate choice; the best-known examples of this pattern occur in some fishes of the family Syngnathidae, though likely examples have also been found in amphibian and bird species. Some features that are confined to one sex only of a particular species can be explained by selection exercised by the other sex in the choice of a mate, for example, the extravagant plumage of some male birds. Similarly, aggression between members of the same sex is sometimes associated with very distinctive features, such as the antlers of stags, which are used in combat with other stags. More generally, intersexual selection is often associated with sexual dimorphism, including differences in body size between males and females of a species.
9.0. Examples of natural selection
9.1. A well-known example of natural selection in action is the development of antibiotic resistance in microorganisms. Since the discovery of penicillin in 1928 by Alexander Fleming, antibiotics have been used to fight bacterial diseases. Natural populations of bacteria contain, among their vast numbers of individual members, considerable variation in their genetic material, primarily as the result of mutations. When exposed to antibiotics, most bacteria die quickly, but some may have mutations that make them slightly less susceptible. If the exposure to antibiotics is short, these individuals will survive the treatment. This selective elimination of maladapted individuals from a population is natural selection.
These surviving bacteria will then reproduce again, producing the next generation. Due to the elimination of the maladapted individuals in the past generation, this population contains more bacteria that have some resistance against the antibiotic. At the same time, new mutations occur, contributing new genetic variation to the existing genetic variation. Spontaneous mutations are very rare, and advantageous mutations are even rarer. However, populations of bacteria are large enough that a few individuals will have beneficial mutations. If a new mutation reduces their susceptibility to an antibiotic, these individuals are more likely to survive when next confronted with that antibiotic. Given enough time, and repeated exposure to the antibiotic, a population of antibiotic-resistant bacteria will emerge.
The widespread use and misuse of antibiotics has resulted in increased microbial resistance to antibiotics in clinical use, to the point that the methicillin-resistant Staphylococcus aureus (MRSA) has been described as a "superbug" because of the threat it poses to health and its relative invulnerability to existing drugs. Response strategies typically include the use of different, stronger antibiotics; however, new strains of MRSA have recently emerged that are resistant even to these drugs. This is an example of what is known as an evolutionary arms race, in which bacteria continue to develop strains that are less susceptible to antibiotics, while medical researchers continue to develop new antibiotics that can kill them. A similar situation occurs with pesticide resistance in plants and insects. Arms races are not necessarily induced by man; a well-documented example involves the elaboration of the RNA interference pathway in plants as means of innate immunity against viruses.
10.0 Evolution by means of natural selection
10.1.A prerequisite for natural selection to result in adaptive evolution, novel traits and speciation, is the presence of heritable genetic variation that results in fitness differences. Genetic variation is the result of mutations, recombinations and alterations in the karyotype (the number, shape, size and internal arrangement of the chromosomes). Any of these changes might have an effect that is highly advantageous or highly disadvantageous, but large effects are very rare. In the past, most changes in the genetic material were considered neutral or close to neutral because they occurred in noncoding DNA or resulted in a synonymous substitution. However, recent research suggests that many mutations in non-coding DNA do have slight deleterious effects. Although both mutation rates and average fitness effects of mutations are dependent on the organism, estimates from data in humans have found that a majority of mutations are slightly deleterious.
The exuberant tail of the peacock is thought to be the result of sexual selection by females. This peacock is an albino; selection against albinos in nature is intense because they are easily spotted by predators or are unsuccessful in competition for mates.
By the definition of fitness, individuals with greater fitness are more likely to contribute offspring to the next generation, while individuals with lesser fitness are more likely to die early or fail to reproduce. As a result, alleles which on average result in greater fitness become more abundant in the next generation, while alleles which generally reduce fitness become rarer. If the selection forces remain the same for many generations, beneficial alleles become more and more abundant, until they dominate the population, while alleles with a lesser fitness disappear. In every generation, new mutations and recombination’s arise spontaneously, producing a new spectrum of phenotypes. Therefore, each new generation will be enriched by the increasing abundance of alleles that contribute to those traits that were favored by selection, enhancing these traits over successive generations.
Some mutations occur in so-called regulatory genes. Changes in these can have large effects on the phenotype of the individual because they regulate the function of many other genes. Most, but not all, mutations in regulatory genes result in non-viable zygotes. Examples of nonlethal regulatory mutations occur in HOX genes in humans, which can result in cervical ribs polydactyl, an increase in the number of fingers or toes. When such mutations result in a higher fitness, natural selection will favor these phenotypes and the novel trait will spread in the population.
Established traits are not immutable; traits that have high fitness in one environmental context may be much less fit if environmental conditions change. In the absence of natural selection to preserve such a trait, it will become more variable and deteriorate over time, possibly resulting in a vestigial manifestation of the trait. In many circumstances, the apparently vestigial structure may retain a limited functionality, or may be co-opted for other advantageous traits in a phenomenon known as preadaptation. A famous example of a vestigial structure, the eye of the blind mole rat, is believed to retain function in photoperiod perception.
10.1.1. Speciation requires selective mating, which result in a reduced gene flow. Selective mating can be the result of, for example, a change in the physical environment (physical isolation by an extrinsic barrier), or by sexual selection resulting in assortative mating. Over time, these subgroups might diverge radically to become different species, either because of differences in selection pressures on the different subgroups, or because different mutations arise spontaneously in the different populations, or because of founder effects - some potentially beneficial alleles may, by chance, be present in only one or other of two subgroups when they first become separated. A lesser-known mechanism of speciation occurs via hybridization, well-documented in plants and occasionally observed in species-rich groups of animals such as cichlid fishes. Such mechanisms of rapid speciation can reflect a mechanism of evolutionary change known as punctuated equilibrium, which suggests that evolutionary change and particularly speciation typically happens quickly after interrupting long periods of stasis.
Genetic changes within groups result in increasing incompatibility between the genomes of the two subgroups, thus reducing gene flow between the groups. Gene flow will effectively cease when the distinctive mutations characterizing each subgroup become fixed. As few as two mutations can result in speciation: if each mutation has a neutral or positive effect on fitness when they occur separately, but a negative effect when they occur together, then fixation of these genes in the respective subgroups will lead to two reproductively isolated populations. According to the biological species concept, these will be two different species.
The modern theory of natural selection derives from the work of Charles Darwin in the nineteenth century.
Several ancient philosophers expressed the idea that nature produces a huge variety of creatures, apparently randomly, and that only those creatures survive that manage to provide for themselves and reproduce successfully; well-known examples include Empedocles and his intellectual successor, Lucretius, while related ideas were later refined by Aristotle. The struggle for existence was later described by al-Jahiz in the 9th century. Such classical arguments were reintroduced in the 18th century by Pierre Louis Maupertuis[ and others, including Charles Darwin's grandfather Erasmus Darwin. While these forerunners had an influence on Darwinism, they later had little influence on the trajectory of evolutionary thought after Charles Darwin.
Until the early 19th century, the prevailing view in Western societies was that differences between individuals of a species were uninteresting departures from their Platonic idealism (or typhus) of created kinds. However, the theory of uniformitarians in geology promoted the idea that simple, weak forces could act continuously over long periods of time to produce radical changes in the Earth's landscape. The success of this theory raised awareness of the vast scale of geological time and made plausible the idea that tiny, virtually imperceptible changes in successive generations could produce consequences on the scale of differences between species. Early 19th century evolutionists such as Jean Baptiste Lamarck suggested the inheritance of acquired characteristics as a mechanism for evolutionary change; adaptive traits acquired by an organism during its lifetime could be inherited by that organism's progeny, eventually causing transmutation of species. This theory has come to be known as Lamarckism and was an influence on the anti-genetic ideas of the Stalinist Soviet biologist Trofim Lysenko.
10.1.3. Darwin’s theory
In 1859, Charles Darwin set out his theory of evolution by natural selection as an explanation for adaptation and speciation. He defined natural selection as the "principle by which each slight variation [of a trait], if useful, is preserved". The concept was simple but powerful: individuals best adapted to their environments are more likely to survive and reproduce. As long as there is some variation between them, there will be an inevitable selection of individuals with the most advantageous variations. If the variations are inherited, then differential reproductive success will lead to a progressive evolution of particular populations of a species, and populations that evolve to be sufficiently different eventually become different species. Darwin's ideas were inspired by the observations that he had made on the Beagle voyage, and by the work of two political economists. The first was the Reverend Thomas Malthus, who in An Essay on the Principle of Population, noted that population (if unchecked) increases exponentially whereas the food supply grows only arithmetically; thus inevitable limitations of resources would have demographic implications, leading to a "struggle for existence" as a divinely ordained law "in order to rouse man into action, and form his mind to reason" for the greater good despite the "partial evil" limiting population. The second was Adam Smith who, in The Wealth of Nations, identified a regulating mechanism in free markets, which he referred to as the "invisible hand", which suggests that prices self-adjust according to supplies and demand. When Darwin read Malthus in 1838 he was already primed by his work as a naturalist to appreciate the "struggle for existence" in nature and it struck him that as population outgrew resources, "favorable variations would tend to be preserved, and unfavorable ones to be destroyed. The result of this would be the formation of new species." Once he had his theory "by which to work", Darwin was meticulous about gathering and refining evidence as his "prime hobby" before making his idea public. He was in the process of writing his "big book" to present his researches when the naturalist Alfred Russel Wallace independently conceived of the principle and described it in an essay he sent to Darwin to forward to Charles Lyell. Lyell and Joseph Dalton Hooker decided (without Wallace's knowledge) to present his essay together with unpublished writings which Darwin had sent to fellow naturalists, and On the Tendency of Species to form Varieties; and on the Perpetuation of Varieties and Species by Natural Means of Selection was read to the Linnean Society announcing co-discovery of the principle in July 1858. Darwin published a detailed account of his evidence and conclusions in On the Origin of Species in 1859. In the 3rd edition of 1861 Darwin acknowledged that others notably William Charles Wells in 1813, and Patrick Matthew in 1831 had proposed similar ideas, but had neither developed them nor presented them in notable scientific publications. Darwin thought of natural selection by analogy to how farmers select crops or livestock for breeding, which he called "artificial selection"; in his early manuscripts he referred to a 'Nature' which would do the selection. At the time, other mechanisms of evolution such as evolution by genetic drift were not yet explicitly formulated, and Darwin believed that selection was likely only part of the story: "I am convinced that [it] has been the main, but not exclusive means of modification." In a letter to Charles Lyell in September 1860, Darwin regretted the use of the term "Natural Selection", preferring the term "Natural Preservation". For Darwin and his contemporaries, natural selection was essentially synonymous with evolution by natural selection. After the publication of The Origin of Species, educated people generally accepted that evolution had occurred in some form. However, natural selection remained controversial as a mechanism, partly because it was perceived to be too weak to explain the range of observed characteristics of living organisms, and partly because even supporters of evolution balked at its "unguided" and non-progressive nature, a response that has been characterized as the single most significant impediment to the idea's acceptance. However, some thinkers enthusiastically embraced natural selection; after reading Darwin, Herbert Spencer introduced the term survival of the fittest, which became a popular summary of the theory. The fifth edition of On the Origin of Species published in 1869 included Spencer's phrase as an alternative to natural selection, with credit given: "But the expression often used by Mr. Herbert Spencer, of the Survival of the Fittest, is more accurate, and is sometimes equally convenient." Although the phrase is still often used by non-biologists, modern biologists avoid it because it is tautological if "fittest" is read to mean "functionally superior" and is applied to individuals rather than considered as an averaged quantity over populations.
10.1.4. Impact of the idea
Darwin's ideas, along with those of Adam Smith and Karl Marx, had a profound influence on 19th century thought. Perhaps the most radical claim of the theory of evolution through natural selection is that "elaborately constructed forms, so different from each other, and dependent on each other in so complex a manner" evolved from the simplest forms of life by a few simple principles. This claim inspired some of Darwin's most ardent supporters—and provoked the most profound opposition. The radicalism of natural selection, according to Stephen Jay Gould, lay in its power to "dethrone some of the deepest and most traditional comforts of Western thought". In particular, it challenged long-standing beliefs in such concepts as a special and exalted place for humans in the natural world and a benevolent creator whose intentions were reflected in nature's order and design.
11.0. Social and psychological theory
11.1. The social implications of the theory of evolution by natural selection also became the source of continuing controversy. Friedrich Engels, a German political philosopher and co-originator of the ideology of communism, wrote in 1872 that "Darwin did not know what a bitter satire he wrote on mankind when he showed that free competition, the struggle for existence, which the economists celebrate as the highest historical achievement, is the normal state of the animal kingdom". Interpretation of natural selection as necessarily 'progressive', leading to increasing 'advances' in intelligence and civilization, was used as a justification for colonialism and policies of eugenics, as well as broader sociopolitical positions now described as Social Darwinism. Konrad Lorenz won the Nobel Prize in Physiology or Medicine in 1973 for his analysis of animal behavior in terms of the role of natural selection (particularly group selection). However, in Germany in 1940, in writings that he subsequently disowned, he used the theory as a justification for policies of the Nazi state. He wrote "... selection for toughness, heroism, and social utility...must be accomplished by some human institution, if mankind, in default of selective factors, is not to be ruined by domestication-induced degeneracy. The racial idea as the basis of our state has already accomplished much in this respect." Others have developed ideas that human societies and culture evolve by mechanisms that are analogous to those that apply to evolution of species.
More recently, work among anthropologists and psychologists has led to the development of sociobiology and later evolutionary psychology, a field that attempts to explain features of human psychology in terms of adaptation to the ancestral environment. The most prominent such example, notably advanced in the early work of Noam Chomsky and later by Steven Pinker, is the hypothesis that the human brain is adapted to acquire the grammatical rules of natural language. Other aspects of human behavior and social structures, from specific cultural norms such as incest avoidance to broader patterns such as gender roles, have been hypothesized to have similar origins as adaptations to the early environment in which modern humans evolved. By analogy to the action of natural selection on genes, the concept of memes - "units of cultural transmission", or culture's equivalents of genes undergoing selection and recombination - has arisen, first described in this form by Richard Dawkins and subsequently expanded upon by philosophers such as Daniel Dennett as explanations for complex cultural activities, including human consciousness. Extensions of the theory of natural selection to such a wide range of cultural phenomena have been distinctly controversial and are not widely accepted.
12.0. Information and systems theory
12.1. In 1922, Alfred Lotka proposed that natural selection might be understood as a physical principle which could be described in terms of the use of energy by a system, a concept that was later developed by Howard Odum as the maximum power principle whereby evolutionary systems with selective advantage maximize the rate of useful energy transformation. Such concepts are sometimes relevant in the study of applied thermodynamics.
The principles of natural selection have inspired a variety of computational techniques, such as "soft" artificial life, that simulate selective processes and can be highly efficient in 'adapting' entities to an environment defined by a specified fitness function. For example, a class of heuristic optimization algorithms known as genetic algorithms, pioneered by John Holland in the 1970s and expanded upon by David E. Goldberg, identify optimal solutions by simulated reproduction and mutation of a population of solutions defined by an initial probability distribution. Such algorithms are particularly useful when applied to problems whose solution landscape is very rough or has many local minima.
13.0. Genetic basis of natural selection
The idea of natural selection predates the understanding of genetics. We now have a much better idea of the biology underlying heritability, which is the basis of natural selection.
13.1.0. Genotype and Phenotype
. Natural selection acts on an organism's phenotype, or physical characteristics. Phenotype is determined by an organism's genetic make-up (genotype) and the environment in which the organism lives. Often, natural selection acts on specific traits of an individual, and the terms phenotype and genotype are used narrowly to indicate these specific traits.
When different organisms in a population possess different versions of a gene for a certain trait, each of these versions is known as an allele. It is this genetic variation that underlies phenotypic traits. A typical example is that certain combinations of genes for eye color in humans which, for instance, give rise to the phenotype of blue eyes. (On the other hand, when all the organisms in a population share the same allele for a particular trait, and this state is stable over time, the allele is said to be fixed in that population.)
Some traits are governed by only a single gene, but most traits are influenced by the interactions of many genes. A variation in one of the many genes that contributes to a trait may have only a small effect on the phenotype; together, these genes can produce a continuum of possible phenotypic values.
13.1.1.Directionality of selection
When some component of a trait is heritable, selection will alter the frequencies of the different alleles, or variants of the gene that produces the variants of the trait. Selection can be divided into three classes, on the basis of its effect on allele frequencies.
Directional selection occurs when a certain allele has a greater fitness than others, resulting in an increase of its frequency. This process can continue until the allele is fixed and the entire population shares the fitter phenotype. It is directional selection that is illustrated in the antibiotic resistance example above.
Far more common is stabilizing selection (also known as purifying selection), which lowers the frequency of alleles that have a deleterious effect on the phenotype - that is, produce organisms of lower fitness. This process can continue until the allele is eliminated from the population. Purifying selection results in functional genetic features, such as protein-coding genes or regulatory sequences, being conserved over time due to selective pressure against deleterious variants.
Finally, a number of forms of balancing selection exist, which do not result in fixation, but maintain an allele at intermediate frequencies in a population. This can occur in diploid species (that is, those that have two pairs of chromosomes) when heterozygote individuals, who have different alleles on each chromosome at a single genetic locus, have a higher fitness than homozygote individuals that have two of the same alleles. This is called heterozygote advantage or overdominance, of which the best-known example is the malarial resistance observed in heterozygous humans who carry only one copy of the gene for sickle cell anemia. Maintenance of allelic variation can also occur through disruptive or diversifying selection, which favors genotypes that depart from the average in either direction (that is, the opposite of over dominance), and can result in a bimodal distribution of trait values. Finally, balancing selection can occur through frequency-dependent selection, where the fitness of one particular phenotype depends on the distribution of other phenotypes in the population. The principles of game theory have been applied to understand the fitness distributions in these situations, particularly in the study of kin selection and the evolution of reciprocal altruism.
14.0. Selection and genetic variation
A portion of all genetic variation is functionally neutral in that it produces no phenotypic effect or significant difference in fitness; the hypothesis that this variation accounts for a large fraction of observed genetic diversity is known as the neutral theory of molecular evolution and was originated by Moto Kimura. Neutral variation was once thought to encompass most of the genetic variation in non-coding DNA, which was hypothesized to be composed of "junk DNA". However, more recently, the functional roles of non-coding DNA, such as the regulatory and developmental functions of RNA gene products, has been studied in depth; large parts of non-protein-coding DNA sequences are highly conserved under strong purifying selection and thus do not vary much from individual to individual, indicating that mutations in these regions have deleterious consequences. When genetic variation does not result in differences in fitness, selection cannot directly affect the frequency of such variation. As a result, the genetic variation at those sites will be higher than at sites where variation does influence fitness.
14.1. Mutation selection balance
Natural selection results in the reduction of genetic variation through the elimination of maladapted individuals and consequently of the mutations that caused the maladaptation. At the same time, new mutations occur, resulting in a mutation-selection balance. The exact outcome of the two processes depends both on the rate at which new mutations occur and on the strength of the natural selection, which is a function of how unfavorable the mutation proves to be. Consequently, changes in the mutation rate or the selection pressure will result in a different mutation-selection balance.
15.0. Genetic linkage
15.1. Genetic linkage occurs when the loci of two alleles are linked, or in close proximity to each other on the chromosome. During the formation of gametes, recombination of the genetic material results in reshuffling of the alleles. However, the chance that such a reshuffle occurs between two alleles depends on the distance between those alleles; the closer the alleles are to each other, the less likely it is that such a reshuffle will occur. Consequently, when selection targets one allele, this automatically results in selection of the other allele as well; through this mechanism, selection can have a strong influence on patterns of variation in the genome.
Selective sweeps occur when an allele becomes more common in a population as a result of positive selection. As the prevalence of one allele increases, linked alleles can also become more common, whether they are neutral or even slightly deleterious. This is called genetic hitchhiking. A strong selective sweep results in a region of the genome where the positively selected haplotype (the allele and its neighbors) are essentially the only ones that exist in the population.
Whether a selective sweep has occurred or not can be investigated by measuring linkage disequilibrium, or whether a given haplotype is overrepresented in the population. Normally, genetic recombination results in a reshuffling of the different alleles within a haplotype, and none of the haplotypes will dominate the population. However, during a selective sweep, selection for a specific allele will also result in selection of neighboring alleles. Therefore, the presence of strong linkage disequilibrium might indicate that there has been a 'recent' selective sweep, and this can be used to identify sites recently under selection.
Background selection is the opposite of a selective sweep. If a specific site experiences strong and persistent purifying selection, linked variation will tend to be weeded out along with it, producing a region in the genome of low overall variability. Because background selection is a result of deleterious new mutations, which can occur randomly in any haplotype, it produces no linkage disequilibrium.
16.0. Theory of natural selection
16.1. Theory of natural selection may be applied to psychological, as well as biological traits. This is known as evolutionary psychology or the evolutionary perspective.
The basic idea of evolutionary psychology is this; genetic mutations are capable of altering not only an organism's physical traits, but also its behavioral traits. Like physical traits, these mutations may help the organism reproduce and pass its mutation on to the next generation. This theory explains how behaviors like mating rituals and migration came to be multi-generation rituals in some species.
16.2. Controversy Surrounding
Presently, the evolutionary psychology perspective is extremely controversial as it is unable to be scientifically proven in a laboratory setting and is, by definition, very susceptible to hind-sight bias.
17.0.In Early Human Development
Consider the following- in a population's gene pool, the normal genotype is for an infant that is unattached to its mother- it will crawl away and does not have any "love" or other significant attachment to its mother. Over time, mutations accumulate and there develops another genotype that causes infants to become uncomfortable and cry when their mothers leave. Naturally, the crying infant that signals distress will have more protection from the elements and other predatory environmental forces. Thus, the "attached" infant will have a higher chance of survival. Over many generations, more "attached" infants will survive to mate and pass on the allele for secure attachment. Thus, a new behavior has developed by means of natural selection. This illustrates the basic idea behind evolutionary psychology in human development; that the innate behaviors of very young children are pre-programmed in their genotypes and that we can understand these behaviors by studying the environmental forces that surrounded our ancestors.
18.0.The Nature-Nurture Controversy
One of the central debates in psychology involves the origin of human behavior. Is it, as theorized by many, caused by biological factors present in the human body, or is it caused by interactions between the individual and its environment (including other individuals of its species) that finally lead to changes in both behavior and even physical structure? This debate has often been termed Nature versus Nuture, and is not an easy one to solve.
18.1.Nature Human behavior is the result of already-present biological factors Strict adherents of the nature philosophy often use genetic code as support for their theory. It contains the instructions for millions of protein commands that eventual determine our basic structure as human beings. But is it definitive? And can it be changed?
18.2.Nurture Human behavior is the result of interaction with ones environment As for Nature adherents, there is also strong evidence that supports followers of the Nurture philosophy. It is well documented that interaction with ones environment can provoke changes in brain structure and chemistry, and that situations of extreme stress can cause problems like depression.
The base of the nervous system is the neuron. Neurons are cells that are specialized for communicating information. They are the basic tissue and element of the nervous system.
19.1.0.Neurons have a basic structure of:
One cell body
One or more dendrites
19.1.1. The cell body (or soma) is the bulbous end of a neuron, containing the cell nucleus. The soma makes use of nutrients to supply energy for neuronal activity.
19.1.2.Axons are organelles that carry information away from the cell body. Axons may be as small as several microns or as long as several meters in giraffes and whales. The axons main job is to send a signal to the dendrites of another neuron, but some say that they may also receive signals in certain situations. Each neuron has only one axon, but the axon may have branches with what are called terminal buttons at its end.
19.1.3.Dendrites are organelles that sense the neurotransmitter secreted by the axon of another neuron. Most neurons have more than one dendrite. Dendrites and axons do not directly touch each other; there is a gap, called a synapse.
20.0.The Transmission of the Signal
The transmission of the signal is basically the same in all cells, the signal is sent across the synapse by the axon and the dendrite of the next cell picks up the signal.
20.1.1. The synapse is a gap between two cells. Synapse is one way junctions between neurons and other cells. The neurotransmitter is emitted from the axon of one cell and usually goes to the dendrite of the next cell. Sometimes the signal goes to the soma or the axon of the next cell instead of the dendrite (Arnold Wittig 2001).
The terminal button at the end of the axon holds the synaptic vesicles. When the signal reaches the end of the axon the vesicles discharge a chemical called a neuro transmitter. Neurotransmitters are chemicals that are used to relay, amplify and modulate electrical signals between a neuron and another cell. There are approximately 40 to 60 different chemicals that are used as neurotransmitters. The neurotransmitters from the axon fit into receptors of the dendrite on the next neuron. They will then either excite the cell or make it fire or inhibit it and stop it from doing so. The sum of the excitation and inhibition of the neuron is called the graded potential. If the graded potential is greater than that cells threshold then the cell fires, sending the message to the next cell.
20.1.3. Resting Potential
When the cell hasn't fired for a certain amount of time it is considered at its resting potential. The resting potential of a neuron is approx. 70 mV because the membrane surrounding the cell lets in positive potassium ions (K+) and negative chloride ions (Cl-) and keeps out positive sodium ions (Na+). It is easier to fire a cell that is at its resting potential than one that is in the refractory phase.
20.1.4. Action Potential
When the graded potential passes the neurons threshold, an action potential takes place. The action potential sends the signal the entire length of the cell and never dies within the cell, which can be referred to as the all-or-none-principle. During firing the inside of the cell becomes positive, which is sometimes incorrectly called Depolarization and should be called the raising phase of the action potential. After the action potential hits its peak the cell starts the refractory phase.
After the action potential changes the neuron from negative to positive there is a refractory phase where it changes back to negative. At the beginning of this period it is impossible for another signal to be transmitted, this is called absolute refractory phase. After the absolute refractory phase is the relative refractory phase where it is possible to send another signal but more excitation than normal is needed.
20.1.6. Signal Strength
For the signal to be passed from one neuron to the next it must have enough energy to break a point called the threshold. Once the threshold is broken the signal is transmitted. The neuron fires at the same strength every time. The strength of a signal is decided by how many different neurons are being fired and at what frequency they are being fired.
20.1.7. Glial cells
The amount of glial cells to every neuron in the nervous system is disputed. Glial cells function as support for the neurons; they produce the myelin sheath, which surrounds some neurons, and also form part of the blood-brain barrier. The blood-brain barrier is a structure that prevents certain substances in the bloodstream from reaching the brain. Many axons are sheathed with tubes of myelin, which is a fatty material. The glial cells produce myelin. The myelin sheaths on axons have gaps, which are called the nodes of Rangier. Myelinated sheaths help transmit information quickly and efficiently.
21.0. Structure and function of the brain
The brain is split up into three major layers, the hindbrain is the first, the second is the midbrain, and the forebrain is last.
The hindbrain is a well-protected central core of the brain and includes the cerebellum, reticular formation, and the brain stem. The cerebellum plays an important role in the integration of sensory perception and motor output. It utilizes constant feedback on body position to fine-tune motor movements. The brain stem contains the puns, and the medulla oblongata. The puns relay sensory information between the cerebellum and cerebrum. The medulla oblongata is the lower portion of the brainstem. It controls autonomic functions such as breathing and vomiting, and relays nerve signals between the brain and spinal cord. The reticular formation is a part of the brain that is involved in stereotypical actions, such as walking, sleeping, and lying down.
This part of the brain is located between the hindbrain and the forebrain making up part of the brain stem. All sensory and motor information going to and from the fore brain and the spinal cord must pass through the midbrain.
The anterior most division of the developing vertebrate brain that contains the most complex neural network in the CNS is the Forebrain. The forebrain has two major divisions, the lower diencephalon, which contains the thalamus and the hypothalamus, and the upper telencephalon, which contains the cerebrum.
21.4. Methods for observing or evaluating brain activity
In the past only two methods of observation were available. The first was observing individuals who have received brain damage and assume that the part of the brain that was damaged controlled the behavior or sense that had changed. The second was connecting electrodes to the outside of someone’s head and recording the readings.
Newer methods include computed tomography (CT scan), positron emission tomography (PET scan), magnetic resonance imaging (MRI), and super conduction quantum interference devices (SQUID).
22.0. Sensation and Perception
Although intimately related, sensation and perception play two complimentary but different roles in how we interpret our world. Sensation refers to the process of sensing our environment through touch, taste, sight, sound, and smell. This information is sent to our brains in raw form where perception comes into play. Perception is the way we interpret these sensations and therefore make sense of everything around us.
This chapter will describe various theories related to these two concepts and explain the important role they play in the field of psychology. Through this chapter, you will gain a better idea of how our senses work and how this information is organized and interpreted.
Sensation is the process by which our senses gather information and send it to the brain. A large amount of information is being sensed at any one time such as room temperature, brightness of the lights, someone talking, a distant train, or the smell of perfume. With all this information coming into our senses, the majority of our world never gets recognized. We don't notice radio waves, x-rays, or the microscopic parasites crawling on our skin. We don't sense all the odors around us or taste every individual spice in our gourmet dinner. We only sense those things we are able too since we don't have the sense of smell like a bloodhound or the sense of sight like a hawk; our thresholds are different from these animals and often even from each other.
The absolute threshold is the point where something becomes noticeable to our senses. It is the softest sound we can hear or the slightest touch we can feel. Anything less than this goes unnoticed. The absolute threshold is therefore the point at which a stimuli goes from undetectable to detectable to our senses.
22.3. Difference Threshold
Once a stimulus becomes detectable to us, how do we recognize if this stimulus changes. When we notice the sound of the radio in the other room, how do we notice when it becomes louder. It's conceivable that someone could be turning it up so slightly that the difference is undetectable. The difference threshold is the amount of change needed for us to recognize that a change has occurred. This change is referred to as the Just Noticeable Difference.
This difference is not absolute, however. Imagine holding a five-pound weight and one pound was added. Most of us would notice this difference. But what if we were holding a fifty-pound weight? Would we notice if another pound were added? The reason many of us would not is because the change required to detect a difference has to represent a percentage. In the first scenario, one pound would increase the weight by 20%, in the second, that same weight would add only an additional 2%. This theory, named after its original observer, is referred to as Weber's Law.
22.4.Signal Detection Theory
Have you ever been in a crowded room with lots of people talking? Situations like that can make it difficult to focus on any particular stimulus, like the conversation we are having with a friend. We are often faced with the daunting task of focusing our attention on certain things while at the same time attempting to ignore the flood of information entering our senses. When we do this, we are making a determination as to what is important to sense and what is background noise. This concept is referred to as signal detection because we attempt detect what we want to focus on and ignore or minimize everything else.
22.5. Sensory Adaptation
The last concept refers to stimuli, which has become redundant or remains unchanged for an extended period of time. Ever wonder why we notice certain smells or sounds right away and then after a while they fade into the background? Once we adapt to the perfume or the ticking of the clock, we stop recognizing it. This process of becoming less sensitive to unchanging stimulus is referred to as sensory adaptation, after all, if it doesn't change, why do we need to constantly sense it?
As mentioned in the introduction, perception refers to interpretation of what we take in through our senses. The way we perceive our environment is what makes us different from other animals and different from each other. In this section, we will discuss the various theories on how our sensation are organized and interpreted, and therefore, how we make sense of what we see, hear, taste, touch, and smell.
23.1.Gestalt Principles of Grouping
The German word "Gestalt" roughly translates to "whole" or "form," and the Gestalt psychologist's sincerely believed that the whole is greater than the sum of its parts. In order to interpret what we receive through our senses, they theorized that we attempt to organize this information into certain groups. This allows us to interpret the information completely without unneeded repetition. For example, when you see one dot, you perceive it as such, but when you see five dots together, you group them together by saying a "row of dots." Without this tendency to group our perceptions, that same row would be seen as "dot, dot, dot, dot, dot," taking both longer to process and reducing our perceptive ability. The Gestalt principles of grouping include four types: similarity, proximity, continuity, and closure.
Similarity refers to our tendency to group things together based upon how similar to each other they are. In the first figure above, we tend to see two rows of red dots and two rows of black dots. The dots are grouped according to similar color. In the next figure, we tend to perceive three columns of two lines each rather than six different lines. The lines are grouped together because of how close they are to each other, or their proximity to one another. Continuity refers to our tendency to see patterns and therefore perceive things as belonging together if they form some type of continuous pattern. In the third figure, although merely a series of dots, it begins to look like an "X" as we perceive the upper left side as continuing all the way to the lower right and the lower left all the way to the upper right. Finally, in the fourth figure, we demonstrate closure, or our tendency to complete familiar objects that have gaps in them. Even at first glance, we perceive a circle and a square.
23.2.Maintaining Perceptual Constancy
Imagine if every time an object changed we had to completely reprocess it. The next time you walk toward a building, you would have to re-evaluate the size of the building with each step, because we all know as we get closer, everything gets bigger. The building that once stood only several inches is now somehow more than 50 feet tall.
Luckily, this doesn't happen. Due to our ability to maintain constancy in our perceptions, we see that building as the same height no matter what distance it is. Perceptual constancy refers to our ability to see things differently without having to reinterpret the object's properties. There are typically three constancies discussed, including size, shape, and brightness.
23.2.1.Size constancy refers to our ability to see objects as maintaining the same size even when our distance from them makes things appear larger or smaller. This holds true for all of our senses. As we walk away from our radio, the song appears to get softer. We understand, and perceive it as being just as loud as before. The difference being our distance from what we are sensing.
Everybody has seen a plate shaped in the form of a circle. When we see that same plate from an angle, however, it looks more like an ellipse. Shape constancy allows us to perceive that plate as still being a circle even though the angle from which we view it appears to distort the shape.
23.2.2.Brightness constancy refers to our ability to recognize that color remains the same regardless of how it looks under different levels of light. That deep blue shirt you wore to the beach suddenly looks black when you walk indoors. Without color constancy, we would be constantly re-interpreting color and would be amazed at the miraculous conversion our clothes undertake.
We determine distance using two different cues: monocular and binocular. Monocular cues are those cues which can be seen using only one eye. They include size; texture, overlap, shading, height, and clarity.
23.3.1.Size refers to the fact that larger images are perceived as closer to us, especially if the two images are of the same object. The texture of objects tend to become smoother as the object gets farther away, suggesting that more detailed textured objects are closer. Due to overlap, those objects covering part of another object is perceived as closer. The shading or shadows of objects can give a clue to their distance, allowing closer objects to cast longer shadows which will overlap objects which are farther away. Objects which are closer to the bottom of our visual field are seen as closer to us due to our perception of the horizon, where higher (height) means farther away. Similar to texture, objects tend to get blurry as they get farther away, therefore, clearer or more crisp images tend to be perceived as closer (clarity).
23.3.2. Binocular cues refer to those depth cues in which both eyes are needed to perceive. There are two important binocular cues; convergence and retinal disparity.
23.3.3. Convergence refers to the fact that the closer an object, the more inward our eyes need to turn in order to focus. The farther our eyes converge the closer an object appears to be. Since our eyes see two images, which are then sent to our brains for interpretation, the distance between these two images, or their retinal disparity, provides another cue regarding the distance of the object.
24.1. Consciousness is the awareness we have of our environment and ourselves. Different states of consciousness are associated with different patterns of brain waves. Brain waves are tracings of electrical activity that is going on in the brain. Scientists record brain waves using an electroencephalograph (EEG), which monitors electrical activity through electrodes placed on the scalp. There are four main types of brain waves: alpha, beta, theta, and delta.
24.2. Type of Brain Wave Corresponding Mental State
1. Alpha -Very relaxed or meditating
2. Beta- Awake and alert
3. Theta- Lightly asleep
4. Delta- Deeply asleep
Sleep is just one of many types of consciousness we experience, and sleep itself comprises several states of consciousness. Even when we’re sleeping, our brains and bodies continue to work.
24.2.2. Biological Rhythms
Sleep is affected by biological rhythms or periodic physiological changes. Biological rhythms are regular, periodic changes in a body’s functioning. There are three types of biological rhythms:
24.2.3. Circadian rhythms:
Biological cycles that occur about every twenty-four hours are known as Circadian rhythms. Sleep follows a circadian rhythm. Hormone secretion, blood pressure, body temperature, and urine production also have circadian rhythms.
24.2.4. Infradian rhythms
Biological cycles that takes longer than twenty-four hours. For example, women’s menstrual cycles occur about every twenty-eight days.
24.2.5. Ultradian rhythms
Biological cycles that occur more than once a day. Sleep follows an ultradian rhythm of about ninety minutes as well as a circadian rhythm. Alertness and hormone levels also follow ultradian rhythms.
Biological rhythms usually synchronize with environmental events such as changes in daylight. However, experiments have shown that many biological rhythms continue to have the same cycle even without cues from the environment. Such biological rhythms are endogenous, which means that they originate from inside the body rather than depend on outside cues.
24.2.6. Biological Clocks
Endogenous rhythms exist because the body has biological clocks that keep time. Biological clocks can be adjusted by environmental cues, such as changes in temperature. In humans, the suprachiasmatic nucleus (SCN) is the main biological clock that regulates circadian rhythms of sleep. The SCN lies in the brain’s hypothalamus. When light stimulates receptors in the retina of the eye, the receptors send signals to the SCN. The SCN then sends signals to the nearby pineal gland, which secretes melatonin, a hormone that regulates the sleep cycle.
Jet lag is the fatigue and disorientation air travelers feel after a long flight. Although traveling itself drains energy, the time change also contributes to fatigue. People experience jet lag when
the events in their environment are out of sync with their biological clocks. Example: A traveler leaves New York City at eight in the morning and arrives in London about seven hours later. For her, it’s three in the afternoon, but because of the time change, in London it’s eight in the evening. Her body, thinking it’s mid-afternoon, will be confused by the lack of sunlight, and she’ll experience jet lag.
24.2.8.The Function of Sleep
Although everyone sleeps, no one really knows why people sleep. Researchers have proposed several theories to explain how sleep evolved to be a necessary behavior: People conserve energy by sleeping periodically. Sleep has a protective function, as it keeps people tucked away at night, safe from predators. Sleep restores body tissues that are depleted during daily activities. Sleep research has provided a lot of information about what happens to the brain and body during sleep. Researchers study sleep by monitoring subjects who spend the night in labs, and they use various instruments for different purposes: Electroencephalographs (EEGs): record brain waves Electromyography (EMGs): record muscle activity Electrooculographs (EOGs): record eye movements Electrocardiographs (EKGs): record the activity of the heart Other instruments monitor breathing, body temperature, and pulse.
25.0. Sleep Stages
During one night’s sleep, people pass through several cycles of sleep, each lasting about ninety to one hundred minutes. There are five distinct stages of sleep in each cycle: 1, 2, 3, 4, and REM. Stages 1–4 when people are relaxed and ready to fall asleep, their EEG will show mostly alpha waves. When people fall asleep, they enter into stage 1 sleep, which lasts just a few minutes. In stage 1, the EEG shows mostly theta waves. Heart rate, breathing rate, and body temperature drop, and muscles relax. Fantasies or bizarre images may float around in the mind. After a few minutes of stage 1 sleep, people move into stage 2 sleep. Stage 2 lasts about twenty minutes and is characterized by short bursts of brain waves called sleep spindles. People then pass into slow-Wave sleep, which occurs during stages 3 and 4. In stages 3 and 4, which together last about thirty minutes, the EEG displays mostly delta waves. People in stage 3 and 4 sleep show slow breathing and pulse rates, have limp muscles, and are difficult to rouse.
Most people in stage 4 sleep are still, quiet, and difficult to rouse. Sleepwalkers, however, sometimes become physically active during stage 4. They may get up and walk around their room or even carry on a conversation, take a bath, cook, or go outside and get in their car. Because they are in a deep sleep, most sleepwalkers remember nothing of their actions when they wake up.
REM Sleep At the end of stage 4, people go back through the stages in reverse, from stage 4 to 3 to 2 to 1. When they reach stage 1, instead of waking up, people go into REM, or rapid eye movement, sleep. A single cycle might look like this: 1 2 3 4 3 2 REM . REM sleep is a stage of deep sleep in which, paradoxically, brain wave activity resembles that of an alert person. REM sleep is also called paradoxical sleep. During REM sleep, pulse rate and breathing become irregular, eyes move rapidly under closed lids, and muscles remain very relaxed. Genital arousal also happens during REM. In women, the clitoris becomes swollen with blood, and vaginal lubrication increases. In men, the penis becomes erect. EEGs show mostly beta waves during REM sleep. Although dreaming happens in other sleep stages as well, dreams are most vivid and frequent during REM sleep. People typically go through about four sleep cycles during one night of sleep. The REM stage of sleep gets longer and longer as the night passes, while stage 3 and 4 sleep gets shorter and shorter. During the nights first sleep cycle, the REM stage lasts about ten minutes. During the nights last sleep cycle people may spend about forty - sixty minutes in REM sleep. Non-REM sleep becomes shallower as the night goes on, and eventually the sleeper awakens.
25.2. Sleep Deprivation
Different people need different amounts of sleep. Some people can function with fewer than six hours of sleep a night, while others can’t manage without at least nine hours. Research shows that getting insufficient sleep can have negative effects on health, productivity, and performance. Researchers have also studied the effects of insufficient REM sleep. Experiment subjects who are intentionally deprived of REM sleep tend to enter the REM stage of sleep more and more frequently during the night. After an REM-deprivation experiment has ended, subjects usually experience a REM rebound effect, spending more time in the REM stage on subsequent nights to make up for lost REM time.
25.3. Aging and Sleep
Sleep patterns change as people get older. Newborn babies spend about two-thirds of their time in sleep. As people age, they tend to sleep less. The amount of time spent in REM sleep also changes over time. In very young babies, about half of all sleep is REM sleep. As babies get older, the proportion of REM sleep decreases.
25.4. Sleep Disorders
Everyone has occasional difficulty sleeping, but some people have insomnia, a chronic problem with falling or staying asleep. Another kind of sleep disorder is narcolepsy, which is a tendency to fall asleep periodically during the day. Narcolepsy can be dangerous, as people who experience it may fall asleep while driving or operating machinery. Sleep apnea is another condition that can have negative effects on health and safety. People who have sleep apnea stop breathing many times during a night’s sleep, and each time they stop breathing, they wake up briefly and gasp for air. This prevents them from getting enough deep sleep, which leads to irritability and sleepiness during the day. Chronic sleep apnea can also result in high blood pressure.
26.0.Development, Personality, and Stage Theories
When discussing any type of development, most theorists break it down into specific stages. These stages are typically progressive. In other words, you must pass through one stage before you can get to the next. Think about how you learned to run; first you had to learn to crawl, then you could learn to walk, and finally you could develop the skills needed to run. Without the first two stages, running would be impossibility.
26.1. Motor Development in Infancy and Childhood
Most infants develop motor abilities in the same order and at approximately the same age. In this sense, most agree that these abilities are genetically preprogrammed within all infants. The environment does play a role in the development, with an enriched environment often reducing the learning time and an impoverished one doing the opposite.
The following chart delineates the development of infants in sequential order. The ages shown are averages and it is normal for these to vary by a month or two in either direction.
2 months – able to lift head up on his own
3 months – can roll over
4 months – can sit propped up without falling over
6 months – is able to sit up without support
7 months – begins to stand while holding on to things for support
9 months – can begin to walk, still using support
10 months – is able to momentarily stand on her own without support
11 months – can stand alone with more confidence
12 months – begin walking alone without support
14 months – can walk backward without support
17 months – can walk up steps with little or no support
18 months – able to manipulate objects with feet while walking, such as kicking a ball
26.2.Cognitive Development in Children
Probably the most cited theory in the cognitive development in children is Jean Piaget (1896-1980). As with all stage theories, Piaget’s Theory of Cognitive Development maintains that children go through specific stages as their intellect and ability to see relationships matures. These stages are completed in a fixed order with all children, even those in other countries. The age range however, can vary from child to child.
26.2.1. Sensor motor Stage. This stage occurs between the ages of birth and two years of age, as infants begin to understand the information entering their sense and their ability to interact with the world. During this stage, the child learns to manipulate objects although they fail to understand the permanency of these objects if they are not within their current sensory perception. In other words, once an object is removed from the child’s view, he or she is unable to understand that the object still exists. The major achievement during this stage is that of Object Permanency, or the ability to understand that these objects do in fact continue to exist. This includes his ability to understand that when mom leaves the room, she will eventually return, resulting in an increased sense of safety and security. Object Permanency occurs during the end of this stage and represents the child’s ability to maintain a mental image of the object (or person) without the actual perception.
26.2.2. Preoperational Stage. The second stage begins after Object Permanency is achieved and occurs between the ages of two to seven years of age. During this stage, the development of language occurs at a rapid pace. Children learn how to interact with their environment in a more complex manner through the use of words and images. This stage is marked by Egocentrism, or the child’s belief that everyone sees the world the same way that she does. The fail to understand the differences in perception and believe that inanimate objects have the same perceptions they do, such as seeing things, feeling, hearing and their sense of touch.
A second important factor in this stage is that of Conservation, which is the ability to understand that quantity does not change if the shape changes. In other words, if a short and wide glass of water is poured into a tall and thin glass. Children in this stage will perceive the taller glass as having more water due only because of its height. This is due to the children’s inability to understand reversibility and to focus on only one aspect of a stimulus (called centration), such as height, as opposed to understanding other aspects, such as glass width.
26.2.3. Concrete Operations Stage. Occurring between ages 7 and about 12, the third stage of cognitive development is marked by a gradual decrease in centristic thought and the increased ability to focus on more than one aspect of a stimulus. They can understand the concept of grouping, knowing that a small dog and a large dog are still both dogs or that pennies, quarters, and dollar bills are part of the bigger concept of money. They can only apply this new understanding to concrete objects (those they have actually experienced). In other words, imagined objects or those they have not seen, heard, or touched, continue to remain somewhat mystical to these children, and abstract thinking has yet to develop.
26.2.4. Formal Operations Stage. In the final stage of cognitive development (from age 12 and beyond), children begin to develop a more abstract view of the world. They are able to apply reversibility and conservation to both real and imagined situations. They also develop an increased understanding of the world and the idea of cause and effect. By the teenage years, they are able to develop their own theories about the world. Most children achieve this stage, although failure to do so has been associated with lower intelligence.
27.0.Erikson’s Stages of Psychosocial Development
Like Piaget, Erik Erikson (1902-1994) maintained that children develop in a predetermined order. Instead of focusing on cognitive development, however, he was interested in how children socialize and how this affects their sense of self. Erikson’s Theory of Psychosocial Development has eight distinct stage, each with two possible outcomes. According to the theory, successful completion of each stage results in a healthy personality and successful interactions with others. Failure to successfully complete a stage can result in a reduced ability to complete further stages and therefore a more unhealthy personality and sense of self. These stages, however, can be resolved successfully at a later time.
27.1.0.Trust Versus Mistrust. From birth to one year, children begin to learn the ability to trust others based upon the consistency of their caregiver(s). If trust develops successfully, the child gains confidence and security in the world around him and is able to feel secure even when threatened. Unsuccessful completion of this stage can result in an inability to trust, and therefore an sense of fear about the inconsistent world. It may result in anxiety, heightened insecurities, and an over feeling of mistrust in the world around them.
27.1.1. Autonomy vs. Shame and Doubt. Between the ages of one and three, children begin to assert their independence, by walking away from their mother, picking which toy to play with, and making choices about what they like to wear, to eat, etc. If children in this stage are encouraged and supported in their increased independence, they become more confident and secure in their own ability to survive in the world. If children are criticized, overly controlled, or not given the opportunity to assert themselves, they begin to feel inadequate in their ability to survive, and may then become overly dependent upon others, lack self-esteem, and feel a sense of shame or doubt in their own abilities.
27.1.2. Initiative vs. Guilt. Around age three and continuing to age six, children assert themselves more frequently. They begin to plan activities, make up games, and initiate activities with others. If given this opportunity, children develop a sense of initiative, and feel secure in their ability to lead others and make decisions. Conversely, if this tendency is squelched, either through criticism or control, children develop a sense of guilt. They may feel like a nuisance to others and will therefore remain followers, lacking in self-initiative.
27.1.3. Industry vs. Inferiority. From age six years to puberty, children begin to develop a sense of pride in their accomplishments. They initiate projects, see them through to completion, and feel good about what they have achieved. During this time, teachers play an increased role in the child’s development. If children are encouraged and reinforced for their initiative, they begin to feel industrious and feel confident in their ability to achieve goals. If this initiative is not encouraged, if it is restricted by parents or teacher, then the child begins to feel inferior, doubting his own abilities and therefore may not reach his potential.
27.1.4. Identity vs. Role Confusion. During adolescence, the transition from childhood to adulthood is most important. Children are becoming more independent, and begin to look at the future in terms of career, relationships, families, housing, etc. During this period, they explore possibilities and begin to form their own identity based upon the outcome of their explorations. This sense of who they are can be hindered, which results in a sense of confusion ("I don’t know what I want to be when I grow up") about themselves and their role in the world.
27.1.5. Intimacy vs. Isolation. Occurring in Young adulthood, we begin to share ourselves more intimately with others. We explore relationships leading toward longer-term commitments with someone other than a family member. Successful completion can lead to comfortable relationships and a sense of commitment, safety, and care within a relationship. Avoiding intimacy, fearing commitment and relationships can lead to isolation, loneliness, and sometimes depression.
27.1.6. Generativity vs. Stagnation. During middle adulthood, we establish our careers, settle down within a relationship, begin our own families and develop a sense of being a part of the bigger picture. We give back to society through raising our children, being productive at work, and becoming involved in community activities and organizations. By failing to achieve these objectives, we become stagnant and feel unproductive.
27.1.7.Ego Integrity vs. Despair. As we grow older and become senior citizens, we tend to slow down our productivity, and explore life as a retired person. It is during this time that we contemplate our accomplishments and are able to develop integrity if we see ourselves as leading a successful life. If we see our lives as unproductive, feel guilt about our pasts, or feel that we did not accomplish our life goals, we become dissatisfied with life and develop despair, often leading to depression and hopelessness.
28.0.Freud’s Stages of Psychosexual Development
Sigmund Freud (1856-1939) is probably the most well known theorist when it comes to the development of personality. Freud’s Stages of Psychosexual Development are, like other stage theories, completed in a predetermined sequence and can result in either successful completion or a healthy personality or can result in failure, leading to an unhealthy personality. This theory is probably the most well known as well as the most controversial, as Freud believed that we develop through stages based upon a particular erogenous zone. During each stage, an unsuccessful completion means that a child becomes fixated on that particular erogenous zone and either over– or under-indulges once he or she becomes an adult.
28.1.0. Oral Stage (Birth to 18 months). During the oral stage, the child is focused on oral pleasures (sucking). Too much or too little gratification can result in an Oral Fixation or Oral Personality, which is evidenced by a preoccupation with oral activities. This type of personality may have a stronger tendency to smoke, drink alcohol, over eat, or bite his or her nails. Personality wise, these individuals may become overly dependent upon others, gullible, and perpetual followers. On the other hand, they may also fight these urges and develop pessimism and aggression toward others.
28.1.1. Anal Stage (18 months to three years). The child’s focus of pleasure in this stage is on eliminating and retaining feces. Through society’s pressure, mainly via parents, the child has to learn to control anal stimulation. In terms of personality, after effects of an anal fixation during this stage can result in an obsession with cleanliness, perfection, and control (anal retentive). On the opposite end of the spectrum, they may become messy and disorganized (anal expulsive).
28.1.2. Phallic Stage (ages three to six). The pleasure zone switches to the genitals. Freud believed that during this stage boy develop unconscious sexual desires for their mother. Because of this, he becomes rivals with his father and sees him as competition for the mother’s affection. During this time, boys also develop a fear that their father will punish them for these feelings, such as by castrating them. This group of feelings is known as Oedipus Complex ( after the Greek Mythology figure who accidentally killed his father and married his mother).
Later it was added that girls go through a similar situation, developing unconscious sexual attraction to their father. Although Freud Strongly disagreed with this, it has been termed the Electra Complex by more recent psychoanalysts.
According to Freud, out of fear of castration and due to the strong competition of his father, boys eventually decide to identify with him rather than fight him. By identifying with his father, the boy develops masculine characteristics and identifies himself as a male, and represses his sexual feelings toward his mother. A fixation at this stage could result in sexual deviancies (both overindulging and avoidance) and weak or confused sexual identity according to psychoanalysts.
28.1.3. Latency Stage (age six to puberty). It’s during this stage that sexual urges remain repressed and children interact and play mostly with same sex peers.
28.1.4. Genital Stage (puberty on). The final stage of psychosexual development begins at the start of puberty when sexual urges are once again awakened. Through the lessons learned during the previous stages, adolescents direct their sexual urges onto opposite sex peers, with the primary focus of pleasure is the genitals.
29.0. Freud's Structural and Topographical Models of Personality
Sigmund Freud's Theory is quite complex and although his writings on psychosexual development set the groundwork for how our personalities developed, it was only one of five parts to his overall theory of personality. He also believed that different driving forces develop during these stages that play an important role in how we interact with the world.
29.1.Structural Model (id, ego, superego)
According to Freud, we are born with our Id. The id is an important part of our personality because as newborns, it allows us to get our basic needs met. Freud believed that the id is based on our pleasure principle. In other words, the id wants whatever feels good at the time, with no consideration for the reality of the situation. When a child is hungry, the id wants food, and therefore the child cries. When the child needs to be changed, the id cries. When the child is uncomfortable, in pain, too hot, too cold, or just wants attention, the id speaks up until his or her needs are met.
The id doesn't care about reality, about the needs of anyone else, only its own satisfaction. If you think about it, babies are not real considerate of their parents' wishes. They have no care for time, whether their parents are sleeping, relaxing, eating dinner, or bathing. When the id wants something, nothing else is important.
Within the next three years, as the child interacts more and more with the world, the second part of the personality begins to develop. Freud called this part the Ego. The ego is based on the reality principle. The ego understands that other people have needs and desires and that sometimes being impulsive or selfish can hurt us in the long run. It’s the ego's job to meet the needs of the id, while taking into consideration the reality of the situation.
By the age of five, or the end of the phallic stage of development, the Superego develops. The Superego is the moral part of us and develops due to the moral and ethical restraints placed on us by our caregivers. Many equate the superego with the conscience as it dictates our belief of right and wrong.
In a healthy person, according to Freud, the ego is the strongest so that it can satisfy the needs of the id, not upset the superego, and still take into consideration the reality of every situation. Not an easy job by any means, but if the id gets too strong, impulses and self gratification take over the person's life. If the superego becomes to strong, the person would be driven by rigid morals, would be judgmental and unbending in his or her interactions with the world. You'll learn how the ego maintains control as you continue to read.
29.2. Topographical Model
Freud believed that the majority of what we experience in our lives, the underlying emotions, beliefs, feelings, and impulses are not available to us at a conscious level. He believed that most of what drives us is buried in our unconscious. If you remember the Oedipus and Electra Complex, they were both pushed down into the unconscious, out of our awareness due to the extreme anxiety they caused. While buried there, however, they continue to impact us dramatically according to Freud.
The role of the unconscious is only one part of the model. Freud also believed that everything we are aware of is stored in our conscious. Our conscious makes up a very small part of who we are. In other words, at any given time, we are only aware of a very small part of what makes up our personality; most of what we are is buried and inaccessible. The final part is the preconscious or subconscious. This is the part of us that we can access if prompted, but is not in our active conscious. It’s right below the surface, but still buried somewhat unless we search for it. Information such as our telephone number, some childhood memories, or the name of your best childhood friend is stored in the preconscious. Because the unconscious is so large, and because we are only aware of the very small conscious at any given time, this theory has been likened to an iceberg, where the vast majority is buried beneath the water's surface. The water, by the way, would represent: everything that we are not aware of, have not experienced, and that has not been integrated into our personalities, referred to as the non-conscious.
30.0.Ego Defense Mechanisms
We stated earlier that the ego's job was to satisfy the id's impulses, not offend the moralistic character of the superego, while still taking into consideration the reality of the situation. We also stated that this was not an easy job. Think of the id as the 'devil on your shoulder' and the superego as the 'angel of your shoulder.' We don't want either one to get too strong so we talk to both of them, hear their perspective and then make a decision. This decision is the ego talking, the one looking for that healthy balance.
Before we can talk more about this, we need to understand what drives the id, ego, and superego. According to Freud, we only have two drives; sex and aggression. In other words, everything we do is motivated by one of these two drives.
Sex, also called Eros or the Life force, represents our drive to live, prosper, and produce offspring. Aggression, also called Thanatos or our Death force, represents our need to stay alive and stave off threats to our existence, our power, and our prosperity.
Now the ego has a difficult time satisfying both the id and the superego, but it doesn't have to do so without help. The ego has some tools it can use in its job as the mediator - tools that help defend the ego. These are called Ego Defense Mechanisms or Defenses. When the ego has a difficult time making both the id and the superego happy, it will employ one or more of these defenses:
arguing against an anxiety provoking stimuli by stating it doesn't exist
denying that your physician's diagnosis of cancer is correct and seeking a second opinion
taking out impulses on a less threatening target
slamming a door instead of hitting as person, yelling at your spouse after an argument with your boss
avoiding unacceptable emotions by focusing on the intellectual aspects
focusing on the details of a funeral as opposed to the sadness and grief
placing unacceptable impulses in yourself onto someone else
when losing an argument, you state "You're just Stupid;" homophobia
supplying a logical or rational reason as opposed to the real reason
stating that you were fired because you didn't kiss up the the boss, when the real reason was your poor performance
taking the opposite belief because the true belief causes anxiety
having a bias against a particular race or culture and then embracing that race or culture to the extreme
returning to a previous stage of development
sitting in a corner and crying after hearing bad news; throwing a temper tantrum when you don't get your way
pulling into the unconscious
forgetting sexual abuse from your childhood due to the trauma and anxiety
acting out unacceptable impulses in a socially acceptable way
sublimating your aggressive impulses toward a career as a boxer; becoming a surgeon because of your desire to cut; lifting weights to release 'pent up' energy
pushing into the unconscious
trying to forget something that causes you anxiety
Ego defenses are not necessarily unhealthy as you can see by the examples above. In face, the lack of these defenses, or the inability to use them effectively can often lead to problems in life. However, we sometimes employ the defenses at the wrong time or overuse them, which can be equally destructive.
31.0.Kohlberg’s Stages of Moral Development
Although it has been questioned as to whether it applied equally to different genders and different cultures, Kohlberg’s (1973) stages of moral development is the most widely cited. It breaks our development of morality into three levels, each of which is divided further into two stages:
31.1.0.Preconvention Level (up to age nine):
31.1.1.Self Focused Morality
1. Morality is defined as obeying rules and avoiding negative consequences. Children in this stage see rules set, typically by parents, as defining moral law.
2. That which satisfies the child’s needs is seen as good and moral.
31.2.0.Conventional Level (age nine to adolescence):
31.2.1.Other Focused Morality
3. Children begin to understand what their parents, teacher, etc expect of them. Morality is seen as achieving these expectations.
4. Fulfilling obligations as well as following expectations are seen as moral law for children in this stage.
31.3.0.Post conventional Level (adulthood):
31.3.1.Higher Focused Morality
5. As adults, we begin to understand that people have different opinions about morality and that rules and laws vary from group to group and culture to culture. Morality is seen as upholding the values of your group or culture.
6. Understanding your own personal beliefs allow adults to judge themselves and others based upon higher levels of morality. In this stage what is right and wrong is based upon the circumstances surrounding an action. Basics of morality are the foundation with independent thought playing an important role.
32.0.Mind Body Connection
Most experts in the field of psychology and biology agree that the mind and the body are connected in more complex ways than we can even comprehend. Research constantly shows us that the way we think affects the way we behave, the way we feel, and the way our body’s respond. The opposite is also true, physical illness, physical exhilaration, exercising, insomnia all affect the way we feel and behave, but also the way we think about ourselves and the world.
A Neuron is a specialized nerve cell that receives, processes, and transmits information to other cells in the body. We have a fixed number of neurons, which means they do not regenerate. About 10,000 neurons die every day, but since we start out with between ten and 100 billion (Hooper & Teresi, 1987), we only lose about 2% over our lifetime.
Information comes into the neuron through the Dendrites from other neurons. It then continues to the Cell Body – (soma) which is the main part of the neuron, which contains the nucleus and maintains the life sustaining functions of the neuron. The soma processes information and then
Passes it along the Axon. At the end of the axon are bulb-like structures called Terminal Buttons that pass the information on to glands, muscles, or other neurons.
Anatomy of a Neuron
Biochemical substances called neurotransmitters, which we will talk about in more detail shortly, carry information. The terminal buttons and the dendrites of other neurons do not touch, but instead pass the information containing neurotransmitters through a Synapse. Once the neurotransmitter leaves the axon, and passes through the synapse, it is caught on the dendrite by what are termed Receptor Sites.
Neurotransmitters have been studied quite a bit in relation to psychology and human behavior. What we have found is that several neurotransmitters play a role in the way we behave, learn, the way we feel, and sleep. And, some play a role in mental illnesses. The following are those neurotransmitters that play a significant role in our mental health.
32.1.1.Acetylcholine – involved in voluntary movement, learning, memory, and sleep and Too much acetylcholine is associated with depression, and too little in the hippocampus has been associated with dementia.
32.1.2.Dopamine – correlated with movement, attention, and learning and Too much dopamine has been associated with schizophrenia, and too little is associated with some forms of depression as well as the muscular rigidity and tremors found in Parkinson’s disease.
32.1.3.Nor epinephrine – associated with eating, alertness and Too little nor epinephrine has been associated with depression, while an excess has been associated with schizophrenia.
32.1.4.Epinephrine – involved in energy, and glucose metabolism and Too little epinephrine has been associated with depression.
32.1.5.Serotonin – plays a role in mood, sleep, appetite, and impulsive and aggressive behavior and Too little serotonin is associated with depression and some anxiety disorders, especially obsessive-compulsive disorder. Some antidepressant medications increase the availability of serotonin at the receptor sites.
32.1.6.GABA (Gamma-Amino Butyric Acid) – inhibits excitation and anxiety and too little GABA is associated with anxiety and anxiety disorders. Some antianxiety medication increases GABA at the receptor sites.
32.1.7. Endorphins – involved in pain relief and feelings of pleasure and contentedness.
33.0. The Brain and Nervous System
The nervous system is broken down into two major systems: Central Nervous System and Peripheral Nervous System. We’ll discuss the Central Nervous System first.
The Central Nervous System consists of the brain and the spinal cord. The Cerebral Cortex, which is involved in a variety of higher cognitive, emotional, sensory, and motor functions is more developed in humans than any other animal. It is what we see when we picture a human brain, the gray matter with a multitude of folds covering the cerebrum. The brain is divided into two symmetrical hemispheres: left (language, the ‘rational’ half of the brain, associated with analytical thinking and logical abilities) and right (more involved with musical and artistic abilities). The brain is also divided into four lobes:
33.1.1. Frontal – (motor cortex) motor behavior, expressive language, higher-level cognitive processes, and orientation to person, place, time, and situation
33.1.2. Parietal – (somatosensory Cortex) involved in the processing of touch, pressure, temperature, and pain Occipital – (visual cortex) interpretation of visual information
33.1.3. Temporal – (auditory cortex) receptive language (understanding language), as well as memory and emotion
Typically the brain and spinal cord act together, but there are some actions, such as those associated with pain, where the spinal cord acts even before the information enters the brain for processing. The spinal cord consists of the Brainstem, which is involved, in life sustaining functions. Damage to the brainstem is very often fatal. Other parts of the brainstem include the 33.1.4.Medulla Oblongata, which controls heartbeat, breathing, blood pressure, digestion; Reticular Activating System (Reticular Formation), involved in arousal and attention, sleep and wakefulness, and control of reflexes; Pons – regulates states of arousal, including sleep and dreaming.
33.1.5.Cerebellum – balance, smooth movement, and posture
33.1.6.Thalamus – "central switching station" – relays incoming sensory information (except olfactory) to the brain
33.1.7.Hypothalamus – controls the autonomic nervous system, and therefore maintains the body’s homeostasis, which we will discuss later (controls body temperature, metabolism, and appetite. Translates extreme emotions into physical responses.
33.1.8.Limbic System – emotional expression, particularly the emotional component of behavior, memory, and motivation
33.1.9.Amygdala – attaches emotional significance to information and mediates both defensive and aggressive behavior
33.2.0.Hippocampus – involved more in memory, and the transfer of information from short-term to long-term memory
33.3.0. The Peripheral Nervous System is divided into two sub-systems.
33.3.1. The Somatic Nervous System – primary function is to regulate the actions of the skeletal muscles. Often thought of as mediating voluntary activity. The other sub-system, called the Autonomic Nervous System, regulates primarily involuntary activity such as heart rate, breathing, blood pressure, and digestion. Although these activities are considered involuntary, they can be altered either through specific events or through changing our perceptions about a specific experience. This system is further broken down into two complimentary systems: Sympathetic and Parasympathetic Nervous Systems.
33.3.2. The Sympathetic Nervous System controls what has been called the "Fight or Flight" phenomenon because of its control over the necessary bodily changes needed when we are faced with a situation where we may need to defend ourselves or escape. Imagine walking down a dark street at night alone. Suddenly you hear what you suspect are footsteps approaching you rapidly. What happens?
Your Sympathetic Nervous System kicks in to prepare your body: your heart rate quickens to get more blood to the muscles, your breathing becomes faster and deeper to increase your oxygen, blood flow is diverted from the organs so digestion is reduced and the skin gets cold and clammy and rerouted so to speak to the muscles, and your pupils dilate for better vision. In an instant, your body is prepared to either defend or escape.
Now imagine that the footsteps belong to a good friend who catches up to you and offers to walk you home. You feel relief instantly, but your body takes longer to adjust. In order to return everything to normal, the Parasympathetic Nervous System kicks in. This system is slow acting, unlike its counterpart, and may take several minutes or even longer to get your body back to where it was before the scare.
These two subsystems are at work constantly shifting your body to more prepared states and more relaxed states. Every time a potentially threatening experience occurs (e.g., someone slams on their breaks in front of you, you hear a noise in your house at night, you hear a loud bang, a stranger taps you on the shoulder unexpectedly), your body reacts. The constant shifting of control between these two systems keeps your body ready for your current situation.
34.0.Learning Theory and Behavioral Psychology
Learning can be defined as the process leading to relatively permanent behavioral change or potential behavioral change. In other words, as we learn, we alter the way we perceive our environment, the way we interpret the incoming stimuli, and therefore the way we interact, or behave. John B. Watson (1878-1958) was the first to study how the process of learning affects our behavior, and he formed the school of thought known as Behaviorism. The central idea behind behaviorism is that only observable behaviors are worthy of research since other abstraction such as a person’s mood or thoughts are too subjective. This belief was dominant in psychological research in the United Stated for a good 50 years.
Perhaps the most well known Behaviorist is B. F. Skinner (1904-1990). Skinner followed much of Watson’s research and findings, but believed that internal states could influence behavior just as external stimuli. He is considered to be a Radical Behaviorist because of this belief, although nowadays it is believed that both internal and external stimuli influence our behavior.
Behavioral Psychology is basically interested in how our behavior results from the stimuli both in the environment and within ourselves. They study, often in minute detail, the behaviors we exhibit while controlling for as many other variables as possible. Often a grueling process, but results have helped us learn a great deal about our behaviors, the effect our environment has on us, how we learn new behaviors, and what motivates us to change or remain the same.
34.1.0.Classical and Operant Conditioning
34.1.1.Classical Conditioning. One important type of learning, Classical Conditioning, was actually discovered accidentally by Ivan Pavlov (1849-1936). Pavlov was a Russian physiologist who discovered this phenomenon while doing research on digestion. His research was aimed at better understanding the digestive patterns in dogs.
During his experiments, he would put meat powder in the mouths of dogs who had tubes inserted into various organs to measure bodily responses. What he discovered was that the dogs began to salivate before the meat powder was presented to them. Then, the dogs began to salivate as soon as the person feeding them would enter the room. He soon began to gain interest in this phenomenon and abandoned his digestion research in favor of his now famous Classical Conditioning study.
Basically, the findings support the idea that we develop responses to certain stimuli that are not naturally occurring. When we touch a hot stove, our reflex pulls our hand back. It does this instinctually, no learning involved. It is merely a survival instinct. But why now do some people, after getting burned, pull their hands back even when the stove is not turned on? Pavlov discovered that we make associations that cause us to generalize our response to one stimuli onto a neutral stimulus that it is paired with. In other words, hot burner = ouch, stove = burner, therefore, stove = ouch. Pavlov began pairing a bell sound with the meat powder and found that even when the meat powder was not presented, the dog would eventually begin to salivate after hearing the bell. Since the meat powder naturally results in salivation, these two variables are called the unconditioned stimulus (UCS) and the unconditioned response (UCR), respectively. The bell and salivation are not naturally occurring; the dog was conditioned to respond to the bell. Therefore, the bell is considered the conditioned stimulus (CS), and the salivation to the bell, the conditioned response (CR).
The pairing of stimuli today shapes many of our behaviors. Have you ever noticed that certain stimuli, such as the smell of cologne or perfume, a certain song, a specific day of the year, results in fairly intense emotions? It's not that the smell or the song are the cause of the emotion, but rather what that smell or song has been paired with...perhaps an ex-boyfriend or ex-girlfriend, the death of a loved one, or maybe the day you met you current husband or wife. We make these associations all the time and often don’t realize the power that these connections or pairings have on us. But, in fact, we have been classically conditioned.
34.1.2.Operant Conditioning. Another type of learning, very similar to that discussed above, is called Operant Conditioning. The term "Operant" refers to how an organism operates on the environment, and hence, operant conditioning comes from how we respond to what is presented to us in our environment. It can be thought of as learning due to the natural consequences of our actions.
Let's explain that a little further. The classic study of Operant Conditioning involved a cat who was placed in a box with only one way out; a specific area of the box had to be pressed in order for the door to open. The cat initially tries to get out of the box because freedom is reinforcing. In its attempt to escape, the area of the box is triggered and the door opens. The cat is now free. Once placed in the box again, the cat will naturally try to remember what it did to escape the previous time and will once again find the area to press. The more the cat is placed back in the box, the quicker it will press that area for its freedom. It has learned, through natural consequences, how to gain the reinforcing freedom.
We learn this way every day in our lives. Imagine the last time you made a mistake; you most likely remember that mistake and do things differently when the situation comes up again. In that sense, you’ve learned to act differently based on the natural consequences of your previous actions. The same holds true for positive actions. If something you did results in a positive outcome, you are likely to do that same activity again.
35.1. The term reinforce means to strengthen, and is used in psychology to refer to anything stimulus which strengthens or increases the probability of a specific response. For example, if you want your dog to sit on command, you may give him a treat every time he sits for you. The dog will eventually come to understand that sitting when told to will result in a treat. This treat is reinforcing because he likes it and will result in him sitting when instructed to do so.
This is a simple description of a reinforcer (Skinner, 1938), the treat, which increases the response, sitting. We all apply reinforcers everyday, most of the time without even realizing we are doing it. You may tell your child "good job" after he or she cleans their room; perhaps you tell your partner how good he or she look when they dress up; or maybe you got a raise at work after doing a great job on a project. All of these things increase the probability that the same response will be repeated.
There are four types of reinforcement: positive, negative, punishment, and extinction. We’ll discuss each of these and give examples.
35.1.1. Positive Reinforcement. The examples above describe what is referred to as positive reinforcement. Think of it as adding something in order to increase a response. For example, adding a treat will increase the response of sitting; adding praise will increase the chances of your child cleaning his or her room. The most common types of positive reinforcement or praise and rewards, and most of us have experienced this as both the giver and receiver.
35.1.2. Negative Reinforcement. Think of negative reinforcement as taking something negative away in order to increase a response. Imagine a teenager who is nagged by his mother to take out the garbage week after week. After complaining to his friends about the nagging, he finally one day performs the task and to his amazement, the nagging stops. The elimination of this negative stimulus is reinforcing and will likely increase the chances that he will take out the garbage next week.
35.1.3. Punishment. Punishment refers to adding something aversive in order to decrease a behavior. The most common example of this is disciplining (e.g. spanking) a child for misbehaving. The reason we do this is because the child begins to associate being punished with the negative behavior. The punishment is not liked and therefore to avoid it, he or she will stop behaving in that manner.
35.1.4. Extinction. When you remove something in order to decrease a behavior, this is called extinction. You are taking something away so that a response is decreased.
Research has found positive reinforcement is the most powerful of any of these. Adding a positive to increase a response not only works better, but allows both parties to focus on the positive aspects of the situation. Punishment, when applied immediately following the negative behavior can be effective, but results in extinction when it is not applied consistently. Punishment can also invoke other negative responses such as anger and resentment.
Know that we understand the four types of reinforcement, we need to understand how and when these are applied (Ferster & Skinner, 1957). For example, do we apply the positive reinforcement every time a child does something positive? Do we punish a child every time he does something negative? To answer these questions, you need to understand the schedules of reinforcement.
Applying one of the four types of reinforcement every time the behavior occurs (getting a raise after every successful project or getting spanked after every negative behavior) is called a Continuous Schedule. It is continuous because the application occurs after every project, behavior, etc. This is the best approach when using punishment. Inconsistencies in the punishment of children, often results in confusion and resentment. A problem with this schedule is that we are not always present when a behavior occurs or may not be able to apply the punishment.
There are two types of continuous schedules:
35.2.1.Fixed Ratio. A fixed ratio schedule refers to applying the reinforcement after a specific number of behaviors. Spanking a child if you have to ask him three times to clean his room is an example. The problem is that the child (or anyone for that matter) will begin to realize that he can get away with two requests before he has to act. Therefore, the behavior does not tend to change until right before the preset number.
35.2.2.Fixed Interval. Applying the reinforcer after a specific amount of time is referred to as a fixed interval schedule. An example might be getting a raise every year and not in between. A major problem with this schedule is that people tend to improve their performance right before the time period expires so as to "look good" when the review comes around.
When reinforcement is applied on an irregular basis, they are called variable schedules.
35.2.3.Variable Ratio. This refers to applying a reinforcer after a variable number of responses. Variable ratio schedules have been found to work best under many circumstances and knowing an example will explain why. Imagine walking into a casino and heading for the slot machines. After the third coin you put in, you get two back. Two more and you get three back. Another five coins and you receive two more back. How difficult is it to stop playing?
35.2.4.Variable Interval. Reinforcing someone after a variable amount of time is the final schedule. If you have a boss who checks your work periodically, you understand the power of this schedule. Because you don’t know when the next ‘check-up’ might come, you have to be working hard at all times in order to be ready.
In this sense, the variable schedules are more powerful and result in more consistent behaviors. This may not be as true for punishment since consistency in the application is so important, but for all other types of reinforcement they tend to result in stronger responses.
36.0.Memory, Intelligence, and States of Mind
There are various states of mind, how our memory works, why we forget things, the debate over intelligence and intelligence testing, and the power of the mind to control states of relaxation and hypnosis. Obviously there are a lot of things, both internal and external, that can affect our current state. Emotions, noise, stress, and of course the use of alcohol and drugs all come to mind. All of these things should be taken into consideration when learning about states of mind and how to control them.
Human memory, like memory in a computer, allows us to store information for later use. In order to do this, however, both the computer and we need to master three processes involved in memory. The first is called encoding; the process we use to transform information so that it can be stores. For a computer this means transferring data into 1’s and 0’s. For us, it means transforming the data into a meaningful form such as an association with an existing memory, an image, or a sound.
Next is the actual storage, which simply means holding onto the information. For this to take place, the computer must physically write the 1’ and 0’s onto the hard drive. It is very similar for us because it means that a physiological change must occur for the memory to be stored. The final process is called retrieval, which is bringing the memory out of storage and reversing the process of encoding. In other words, return the information to a form similar to what we stored.
The major difference between humans and computers in terms of memory has to do with how the information is stored. For the most part, computers have only two types; permanent storage and permanent deletion. Humans, on the other hand are more complex in that we have three distinct memory storage capabilities (not including permanent deletion). The first is Sensory memory, referring to the information we receive through the senses. This memory is very brief lasting only as much as a few seconds.
36.1.0. Short Term Memory (STM) takes over when the information in our sensory memory is transferred to our consciousness or our awareness (Engle, Cantor, & Carullo, 1993; Laming, 1992). This is the information that is currently active such as reading this page, talking to a friend, or writing a paper. Short term memory can definitely last longer than sensory memory (up to 30 seconds or so), but it still has a very limited capacity. According to research, we can remember approximately 5 to 9 (7 +/- 2) bits of information in our short term memory at any given time (Miller, 1956)
If STM lasts only up to 30 seconds, how do we ever get any work done? Wouldn't we start to lose focus or concentrate about twice every minute? This argument prompted researchers to look at a second phase of STM that is now referred to as Working Memory. Working Memory is the process that takes place when we continually focus on material for longer than STM alone will allow (Baddeley, 1992).
What happens when our short term memory is full and another bit of information enters? 36.1.1.Displacement means that the new information will push out part of the old information. Suddenly some one says the area code for that phone number and almost instantly you forget the last two digits of the number. We can further sharpen our short term memory skills, however, by mastering chunking and using rehearsal (which allows us to visualize, hear, say, or even see the information repeatedly and through different senses).
Finally, there is long term memory (LTM), which is most similar to the permanent storage of a computer. Unlike the other two types, LTM is relatively permanent and practically unlimited in terms of its storage capacity. Its been argued that we have enough space in our LTM to memorize every phone number in the U.S. and still function normally in terms of remembering what we do now. Obviously we don’t use even a fraction of this storage space.
There are several subcategories of LTM. First, memories for facts, life events, and information about our environment are stored in declarative memory. This includes semantic memory, factual knowledge like the meaning of words, concepts, and our ability to do math (Lesch & Pollatsek, 1993, Rohrer et al., 1995) and episodic memory, memories for events and situations (Goldringer, 1996; Kliegel & Lindberger, 1993). The second subcategory is often not thought of as memory because it refers to internal, rather than external information. When you brush your teeth, write your name, or scratch your eye, you do this with ease because you previously stored these movements and can recall them with ease. This is referred to as nondeclarative (or implicit) memory. These are memories we have stored due to extensive practice, conditioning, or habits.
36.2. Why We Remember What We Remember
36.2.0. Short Term Memory. There are typically six reasons why information is stored in our short term memory.
36.2.1. Primacy effect - information that occurs first is typically remembered better than information occurring later. When given a list of words or numbers, the first word or number is usually remembered due to rehearsing this more than other information.
36.2.2.Recency effect - often the last bit of information is remembered better because not as much time has past; time which results in forgetting.
36.2.3. Distinctiveness - if something stands out from information around it, it is often remembered better. Any distinctive information is easier to remember than that which is similar, usual, or mundane.
36.2.4. Frequency effect - rehearsal, as stated in the first example, results in better memory. Remember trying to memorize a formula for your math class. The more you went over it, the better you knew it.
36.2.5. Associations - when we associate or attach information to other information it becomes easier to remember. Many of us use this strategy in our professions and everyday life in the form of acronyms.
36.2.6. Reconstruction - sometimes we actually fill in the blanks in our memory. In other words, when trying to get a complete picture in our minds, we will make up the missing parts, often without any realization that this is occurring.
36.3. Long Term Memory. Information that passes from our short term to our long term memory is typically that which has some significance attached to it. Imagine how difficult it would be to forget the day you graduated, or your first kiss. Now think about how easy it is to forget information that has no significance; the color of the car you parked next to at the store or what shirt you wore last Thursday. When we process information, we attach significance to it and information deemed important is transferred to our long term memory.
There are other reasons information is transferred. As we all know, sometimes our brains seem full of insignificant facts. Repetition plays a role in this, as we tend to remember things more the more they are rehearsed. Other times, information is transferred because it is somehow attached to something significant. You may remember that it was a warm day when you bought your first car. The temperature really plays no important role, but is attached to the memory of buying your first car.
You can’t talk about remembering without mentioning its counterpart. It seems that as much as we do remember, we forget even more. Forgetting isn’t really all that bad, and is in actuality, a pretty natural phenomenon. Imagine if you remembered every minute detail of every minute or every hour, of every day during your entire life, no matter how good, bad, or insignificant. Now imagine trying to sift through it all for the important stuff like where you left your keys.
There are many reasons we forget things and often these reasons overlap. Like in the example above, some information never makes it to LTM. Other times, the information gets there, but is lost before it can attach itself to our LTM. Other reasons include decay, which means that information that is not used for an extended period of time decays or fades away over time. It is possible that we are physiologically preprogrammed to eventually erase data that no longer appears pertinent to us. Failing to remember something doesn’t mean the information is gone forever though. Sometimes the information is there but for various reasons we can’t access it. This could be caused by distractions going on around us or possibly due to an error of association (e.g., believing something about the data which is not correct causing you to attempt to retrieve information that is not there). There is also the phenomenon of repression, which means that we purposefully (albeit subconsciously) push a memory out of reach because we do not want to remember the associated feelings. This is often cited in cases where adults ‘forget’ incidences of sexual abuse when they were children. And finally, amnesia, which can be psychological or physiological in origin.
The assessment of human abilities dates back nearly 4000 years when China used written tests to rate applicants for civil service. Two-thousand years later, during the Hans Dynasty, civil service type exams were used in the areas of law, military, agriculture, and geography. In the early 1800s British diplomats observed the Chinese assessments and modified them for use in Britain and eventually the United States for use in civil service placement.
Sir Francis Galton is a key figure in modern intelligence testing. As the first cousin of Charles Darwin, he attempted to apply Darwin's evolutionary theory to the study of human abilities. He postulate that intelligence was quantifiable and normally distributed. In other words, he believed that we could assign a score to intelligence where the majority of people fall in the average range and the percentage of the population decreases the farther from the middle their score gets.
The first workable intelligence test was developed by French psychologist Alfred Binet. He and his partner, Theodore Simon, were commissioned by the French government to improve the teaching methods for developmentally disabled children. They believed that intelligence was the key to effective teaching, and developed a strategy whereby a mental age (MA) was determined and divided by the child's chronological age (CA). This formula, stated as "MA/CA X 100." Another theorist, Raymond Cattell, described intelligence as having two distinct factors. The first he called Crystallized Intelligence, representing acquired knowledge, and second, Fluid Intelligence, or our ability to use this knowledge.
Sternberg (1988) argued that there are a number of ways to demonstrate intelligence or adaptive functioning. He proposed a model of intelligence referred to as the triarchic theory. According to this model there are three types of intelligence: (1) analytical, or the ability to solve a problem by looking at its components; (2) creative, the ability o use new or ingenious ways to solve problems; and (3) practical, referring to street smarts or common sense. While most IQ tests measure only analytical intelligence, they fail to include practical intelligence which is the most understandable to most of us (Sternberg et al., 1995)
Intelligence is not something we can see or hear, or taste. We can see the results of intelligence...sometimes. Many argue that quantifying intelligence correctly is impossible and all that modern IQ tests do is test our knowledge and abilities. While it is true that a person can learn to improve his or her score, this can only occur if correct responses are taught to the person, which is highly unethical. We have also found that our individual IQ score remains quite consistent as we get older. Some argue, however, that modern IQ tests are prejudiced against certain ethnicities and cultures and tend to result in higher scores for others. Where this leaves us, however, is uncertain. As of today, these IQ tests are the best we have in our attempt to quantify the construct known as intelligence.
36.6.Relaxation and Hypnosis
Many internal and external factors affect how we think, feel, and behave. Although alcohol and drugs have been studied in great detail and have been shown to have both positive and negative effects on our state of mind, though my major focus will be primarily on the internal factors that influence our state of mind, particularly relaxation and hypnosis. These two terms are not foreign to most of us, but they can be highly misunderstood. Let's explore the concept of relaxation first.
When studied in psychology, relaxation refers to a focusing on the mind and a relaxing of the body's muscles. Research has shown that being too tense and/or living with too much stress has a significant negative impact on our lives. It can lead to physical illnesses such as high blood pressure, ulcers, fatigue, and headaches and many psychological issues, including inappropriate or misdirected emotions, confusion, difficulty concentrating, and burn-out. People utilize relaxation, in combination with stress management, to improve their quality of life, reduce the physical components of stress, and improve their psychological functioning.
There are different forms of relaxation, including breathing exercises, deep muscle relaxation, progressive muscle relaxation, imagery, meditation, and yoga. Although each of these has different components, the main goal in each is to relax the body's muscles and focus the mind. Since the body and the mind cannot be separated, most agree that both of these components must be present for any relaxation technique to work.
Hypnosis is very similar to relaxation in that the same two components of physical and mental must be addressed together. Most professionals agree that hypnosis is a very deep state of relaxation where your mind is more focused and the connection between your thoughts, emotions, and behaviors are more clear. Hypnosis is not magical; it can not cause you to do anything against your judgment or ethical beliefs; it can not make you 'cluck like a chicken.' What it can do it help you to focus on specific areas of your life with more clarity and teach you how to do this in a positive manner. A hypnotherapist is typically a licensed professional who uses hypnosis as part of a treatment regimen for certain psychological disorders. It is rarely used as the primary treatment, but instead is most beneficial when used with relaxation and talk-therapy for a more rounded therapeutic approach. A hypnotist is a non-clinical term usually referring to an unlicensed individual who perform various forms of hypnosis for entertainment purposes. The two are quite different, the former is therapeutic and the latter is not designed to be so. Most people are able to be hypnotized, although many factors play a role in your individual susceptibility. These factors include your belief in hypnosis, your trust for the therapist, your sense of safety, ability to concentrate and focus your mind, and the absence of external factors such as noise, uncomfortable temperature, and physical comfort. The key to successful hypnosis is your ability to focus on your body and mind and to trust and believe in your therapist. Without these hypnosis will not work, at least not to the fullest therapeutic value.
37.0.Broadbent's filter theory
Broadbent's theories of selective attention and short-term memory were developed as digital computers were beginning to become available to the academic community, and were among the first to use computer analogies to make a serious contribution to the analysis of human cognition. They were combined to form what became known as the "single channel hypothesis". His Filter Model proposed that the physical characteristics (e.g., pitch, loudness) of an auditorily presented message were used to focus attention to only a single message. Broadbent's Filter model is referred to as an early selection model because irrelevant messages are filtered out before the stimulus information is processed for meaning. These and other theories were brought together in his 1958 book "Perception and Communication" which remains one of the classic texts of cognitive psychology Broadbent's theory accounts for a theoretical filter device, which is located in between the incoming sensory register and the short-term memory storage. His theory is based upon the multi-storage paradigm of William James(1890) and later the Atkinson & Shiffrin's 'multi-store' memory model (1968). This filter functions together with a buffer, and enables the subject to handle two kinds of stimuli, presented at the same time. One of the inputs is allowed through the filter, while the other is waiting in the buffer for later processing. The filter prevents overloading of the limited capacity mechanism beyond the filter, which is the short-term memory. It is based on the famous cocktail party problem of the British scientist Colin Cherry, who is trying to explain how we are able to focus our attention towards the stimuli which we find most interesting. Broadbent comes up with the theory based on data from an experiment where three pairs of different digits are presented simultaneously, three digits in one ear and three in the other. Most participants recalled the digits ear by ear,
rather than pair by pair. Thus, if 496 were presented to one ear and 852 to the other, the recall would be 496852 rather than 489562.
37.1.Relationship with working memory
The relationship between short-term memory and working memory is described differently by various theories, but it is generally acknowledged that the two concepts are distinct. Working memory is a theoretical framework that refers to structures and processes used for temporarily storing and manipulating information. As such, working memory might also be referred to as working attention. Short-term memory generally refers, in a theory-neutral manner, to the short-term storage of information, and it does not entail the manipulation or organization of material held in memory. Thus while there are short-term memory components to working memory models, the concept of short-term memory is distinct from these more hypothetical concepts. Within Baddeley’s influential 1986 model of working memory there are two short-term storage mechanisms: the phonological loop and the visuospatial sketchpad. Most of the research referred to her involves the phonological loop, because most of the work done on short-term memory has used verbal material. In recent years, however, there has been a surge in research on visual short term memory, and also increasing work on spatial short term memory
37.2.Duration of short-term memory
The limited duration of short-term memory immediately suggests that its contents
Spontaneously decay over time. The decay assumption is part of many theories of short-term memory, most notably Baddeley's model of working memory. The decay assumption is usually paired with the idea of rapid covert rehearsal: In order to overcome the limitation of short-term memory, and retain information for longer, information must be periodically repeated, or rehearsed either by articulating it out loud, or by mentally simulating such articulation. In this way, the information will re-enter the short-term store and be retained for a further period.
Several researchers, however, dispute that spontaneous decay plays any significant role in
forgetting over the short term, and the evidence is far from conclusive. Authors doubting that decay causes forgetting from short-term memory often offer as an alternative some form of interference: When several elements (such as digits, words, or pictures) are held in short term memory simultaneously, their representations compete with each other for recall, or degrade
each other. Thereby, new content gradually pushes out older content, unless the older content is actively protected against interference by rehearsal or by directing attention to it.
37.3.Capacity of short-term memory
Whatever the cause or causes of forgetting over the short term may be, there is consensus that it severely limits the amount of new information that we can retain over brief periods of time. This limit is referred to as the finite capacity of short-term memory. The capacity of short-term memory is often called memory span, in reference to a common procedure of measuring it. In a memory span test, the experimenter presents lists of items (e.g. digits or words) of increasing length. An individual's span is determined as the longest list length that he or she can recall correctly in the given order on at least half of all trials. In an early and highly influential article, The Magical Number Seven, Plus or Minus Two, the psychologist George Miller suggested that human short-term memory has a forward memory span of approximately seven items plus or minus two. More recent research has shown that this "magical number seven" is roughly accurate for college students recalling lists of digits, but memory span varies widely with populations tested and with material used. For example, the ability to recall words in order depends on a number of characteristics of these words: fewer words can be recalled when the words have longer spoken duration; this is known as the word-length effect, or when their speech sounds are similar to each other; this is called the phonological similarity effect. More words can be recalled when the words are highly familiar or occur frequently in the language. Recall performance is also better when all of the words in a list are taken from a single semantic category (such as sports) than when the words are taken from different categories. According to the available evidence, the best overall estimate of short-term memory is about four pieces or "chunks" of information. Chunking
Chunking is the process with which we can expand our ability to remember things in the short-term. Chunking is also a process by which a person organizes material into meaningful groups. Although the average person may only retain about four different units in short-term memory, chunking can greatly increase a person's recall capacity. For example, in recalling a phone number, the person could chunk the digits into three groups: first, the area code (such as 215), then a three-digit chunk (123) and lastly a four-digit chunk (4567). This method of remembering phone numbers is far more effective than attempting to remember a string of 10 digits. Practice and the usage of existing information in long-term memory can lead to additional improvements in one's ability to use chunking. In one testing session, an All-
American cross-country runner was able to recall a string of 79 digits after hearing them only once by chunking them into different running times (e.g. the first four numbers were 1518, a three-mile time.)
37.4.Factors Affecting Short Term Memory
It is very difficult to demonstrate the exact capacity of STM due to the fact that it will vary depending on the nature of the material to be recalled. Till now, there is no way of defining the basic unit of information to be stored in the STM store. It is also possible that STM is not the store described by Atkinson and Shiffrin. In that case, the task of defining the task of STM becomes even more difficult. Some other factors are listed below: Reading Aloud: Digital spans tend to increase if the digits are read aloud by participants instead of being read sub-vocally. Baddley (1999) suggests that the sounds are also stored in the echoic store which makes storing it easier.
37.5.1.Working memory is a theoretical construct within cognitive psychology as to the structures and processes used for temporarily storing and manipulating information in short-term memory. Many theories exist both as to the theoretical structure of working memory as well as to the role of specific parts of the brain involved in working memory. Most research identifies that the frontal cortex, parietal cortex, anterior cingulate, and parts of the basal ganglia are crucial for its functioning. The neural basis of working memory mostly comes from lesion experiments in animals and functional imaging upon humans.
The term "working memory" was coined by Miller, Galanter, and Pribram, and was used in the 1960s in the context of theories that likened the mind to a computer. Atkinson and Shiffrin (1968) also used this term, "working memory" (p.92) to describe their "short-term store." What we now call working memory was referred to as a "short-term store" or short-term memory, primary memory, immediate memory, operant memory, or provisional memory. Short-term memory is the ability to remember information over a brief period of time (in the order of seconds). Most theorists today use the concept of working memory to replace or include the older concept of short-term memory, thereby marking a stronger emphasis on the notion of manipulation of information instead of passive maintenance. The earliest mention of experiments on the neural basis of working memory can be traced back to over 100 years ago, when Hitzig and Ferrier described ablation experiments of the prefrontal cortex (PFC). They concluded that the frontal cortex was important for cognitive processes rather than sensory ones. In 1935 and 1936, Jacobsen and colleagues were the first to conclude that the cognitive processes in the PFC were notable in delay-dependent tasks; in other words, they suffered from short-term memory loss.
37.5.3.Theories of working memory
There have been numerous models proposed regarding how working memory functions, both anatomically and cognitively. Of those, three have received the distinct notice of wide acceptance.
37.5.4.The Baddeley and Hitch model
Baddeley and Hitch (1974 introduced and made popular the multicomponent model of working memory. This theory proposes that two "slave systems" are responsible for short-term maintenance of information, and a "central executive" is responsible for the supervision of information integration and for coordinating the slave systems. One slave system, the phonological loop, stores phonological information (i.e., the sound of language) and prevents its decay by continuously articulating its contents, thereby refreshing the information in a rehearsal loop. It can, for example, maintain a seven-digit telephone number for as long as one repeats the number to oneself again and again. The other slave system, the visuo-spatial sketch pad, stores visual and spatial information. It can be used, for example, for constructing and manipulating visual images, and for the representation of mental maps. The sketch pad can be further broken down into a visual subsystem (dealing with, for instance, shape, colour, and texture), and a spatial subsystem (dealing with location). The central executive (see executive system) is, among other things, responsible for directing attention to relevant information, suppressing irrelevant information and inappropriate actions, and for coordinating cognitive processes when more than one task must be done at the same time.
Baddeley (2000) extended the model by adding a fourth component, the episodic buffer, which holds representations that integrate phonological, visual, and spatial information, and possibly information not covered by the slave systems (e.g., semantic information, musical information). The component is episodic because it is assumed to bind information into a unitary episodic representation. The episodic buffer resembles Tulving's concept of episodic memory, but it differs in that the episodic buffer is a temporary store.
37.5.5.The theory of Cowan
Cowan regards working memory not as a separate system, but as a part of long-term memory. Representations in working memory are a subset of the representations in long-term memory. Working memory is organized in two embedded levels. The first level consists of long-term memory representations that are activated. There can be many of these; there is no limit to activation of representations in long-term memory. The second level is called the focus of attention. The focus is regarded as capacity limited and holds up to four of the activated representations. Oberauer has extended the Cowan model by adding a third component, a more narrow focus of attention that holds only one chunk at a time. The one-element focus is embedded in the four-element focus and serves to select a single chunk for processing. For example, you can hold four digits in mind at the same time in Cowan's "focus of attention". Now imagine that you wish to perform some process on each of these digits, for example, adding the number two to each digit. Separate processing is required for each digit, as most individuals can not perform several mathematical processes in parallel. Oberauer's attentional component selects one of the digits for processing, and then shifts the attentional focus to the next digit, continuing until all of the digits have been processed.
37.5.6.The theory of Ericsson and Kintsch
Ericsson and Kintsch (1995) have argued that we use skilled memory in most everyday tasks. Tasks such as reading, for instance, require to maintain in memory much more than seven chunks - with a capacity of only seven chunks our working memory would be full after a few sentences, and we would never be able to understand the complex relations between thoughts expressed in a novel or a scientific text. We accomplish this by storing most of what we read in long-term memory, linking them together through retrieval structures. We need to hold only a few concepts in working memory, which serve as cues to retrieve everything associated to them by the retrieval structures. Anders Ericsson and Walter Kintsch refer to this set of processes as "long-term working memory". Retrieval structures vary according to the domain of expertise, yet as suggested by Gobet they can be categorized in three typologies: generic retrieval structures, domain knowledge retrieval structures and the episodic text structures. The first corresponds to Ericsson and Kintsch’s ‘classic’ retrieval structure and the second to the elaborated memory structure. The first kind of structure is developed deliberately and is arbitrary (e.g. the method of loci), the second one is similar to patterns and schemas and the last one takes place exclusively during text comprehension. Concerning this last typology, Kintsch, Patel and Ericsson consider that every confirmed reader is able to form an episodic text structure during text comprehension, if the text is well written and if the content is familiar. Guido and colleagues using this last feature have proposed the ‘personalization method’ as a way to operationalise the long-term working memory.
37.5.7.Working memory capacity
Working memory is generally considered to have limited capacity. The earliest quantification of the capacity limit associated with short-term memory was the "magical number seven" introduced by Miller (1956). He noticed that the memory span of young adults was around seven elements, called chunks, regardless whether the elements were digits, letters, words, or other units. Later research revealed that span does depend on the category of chunks used (e.g., span is around seven for digits, around six for letters, and around five for words), and even on features of the chunks within a category. For instance, span is lower for long words than for short words. In general, memory span for verbal contents (digits, letters, words, etc.) strongly depends on the time it takes to speak the contents aloud, and on the lexical status of the contents (i.e., whether the contents are words known to the person or not). Several other factors also affect a person's measured span, and therefore it is difficult to pin down the capacity of short-term or working memory to a number of chunks. Nonetheless, Cowan (2001) has proposed that working memory has a capacity of about four chunks in young adults (and fewer in children and old adults). Whereas most adults can repeat about seven digits in correct order, some individuals have shown impressive enlargements of their digit span - up to 80 digits. This feat is possible by extensive training on an encoding strategy by which the digits in a list are grouped (usually in groups of three to five) and these groups are encoded as a single unit (a chunk). To do so one must be able to recognize the groups as some known string of digits. One person studied by K. Anders Ericsson and his colleagues, for example, used his extensive knowledge of racing times from the history of sports. Several such chunks can then be combined into a higher-order chunk, thereby forming a hierarchy of chunks. In this way, only a small number of chunks at the highest level of the hierarchy must be retained in working memory. At retrieval, the chunks are unpacked again. That is, the chunks in working memory act as retrieval cues that point to the digits that they contain. It is important to note that practicing memory skills such as these do not expand working memory capacity proper. This can be shown by using different materials - the person who could recall 80 digits was not exceptional when it came to recalling words.
37.5.8.Measures of working-memory capacity and their correlates
Working memory capacity can be tested by a variety of tasks. A commonly used measure is a dual-task paradigm combining a memory span measure with a concurrent processing task, sometimes referred to as "complex span". Daneman and Carpenter invented the first version of this kind of task, the "reading span", in 1980. Subjects read a number of sentences (usually between 2 and 6) and try to remember the last word of each sentence. At the end of the list of sentences, they repeat back the words in their correct order. Other tasks that don't have this dual-task nature have also been shown to be good measures of working memory capacity. The question of what features a task must have to qualify as a good measure of working memory capacity is a topic of ongoing research.
Measures of working-memory capacity are strongly related to performance in other complex cognitive tasks such as reading comprehension, problem solving, and with any measures of the intelligence quotient. Some researchers have argued that working memory capacity reflects the efficiency of executive functions, most notably the ability to maintain a few task-relevant representations in the face of distracting irrelevant information. The tasks seem to reflect individual differences in ability to focus and maintain attention, particularly when other events are serving to capture attention. These effects seem to be a function of frontal brain areas. Others have argued that the capacity of working memory is better characterized as the ability to mentally form relations between elements, or to grasp relations in given information. This idea has been advanced, among others, by Graeme Halford, who illustrated it by our limited ability to understand statistical interactions between variables. These authors asked people to compare written statements about the relations between several variables to graphs illustrating the same or a different relation, as in the following sentence: "If the cake is from France, then it has more sugar if it is made with chocolate than if it is made with cream, but if the cake is from Italy, then it has more sugar if it is made with cream than if it is made of chocolate." This statement describes a relation between three variables (country, ingredient, and amount of sugar), which is the maximum most individuals can understand. The capacity limit apparent here is obviously not a memory limit (all relevant information can be seen continuously) but a limit on how many relationships are discerned simultaneously.
37.6.0.Experimental studies of working memory capacity
There are several hypotheses about the nature of the capacity limit. One is that there is a limited pool of cognitive resources needed to keep representations active and thereby available for processing, and for carrying out processes. Another hypothesis is that memory traces in working memory decay within a few seconds, unless refreshed through rehearsal, and because the speed of rehearsal is limited, we can maintain only a limited amount of information. Yet another idea is that representations held in working memory capacity interfere with each other. There are several forms of interference discussed by theorists. One of the oldest ideas is that new items simply replace older ones in working memory. Another form of interference is retrieval competition. For example, when the task is to remember a list of 7 words in their order, we need to start recall with the first word. While trying to retrieve the first word, the second word, which is represented in close proximity, is accidentally retrieved as well, and the two compete for being recalled. Errors in serial recall tasks are often confusions of neighboring items on a memory list (so-called transpositions), showing that retrieval competition plays a role in limiting our ability to recall lists in order, and probably also in other working memory tasks. A third form of interference assumed by some authors is feature overwriting. The idea is that each word, digit, or other item in working memory is represented as a bundle of features, and when two items share some features, one of them steals the features from the other. The more items are held in working memory, and the more their features overlap, the more each of them will be degraded by the loss of some features.
None of these hypotheses can explain the experimental data entirely. The resource hypothesis, for example, was meant to explain the trade-off between maintenance and processing: The more information must be maintained in working memory, the slower and more error prone concurrent processes become, and with a higher demand on concurrent processing memory suffers. This trade-off has been investigated by tasks like the reading-span task described above. It has been found that the amount of trade-off depends on the similarity of the information to be remembered and the information to be processed. For example, remembering numbers while processing spatial information, or remembering spatial information while processing numbers, impair each other much less than when material of the same kind must be remembered and processed. Also, remembering words and processing digits, or remembering digits and processing words, is easier than remembering and processing materials of the same category. These findings are also difficult to explain for the decay hypothesis, because decay of memory representations should depend only on how long the processing task delays rehearsal or recall, not on the content of the processing task. A further problem for the decay hypothesis comes from experiments in which the recall of a list of letters was delayed, either by instructing participants to recall at a slower pace, or by instructing them to say an irrelevant word once or three times in between recall of each letter. Delaying recall had virtually no effect on recall accuracy.. The interference hypothesis seems to fare best with explaining why the similarity between memory contents and the contents of concurrent processing tasks affects how much they impair each other. More similar materials are more likely to be confused, leading to retrieval competition, and they have more overlapping features, leading to more feature overwriting. One experiment directly manipulated the amount of overlap of phonological features between words to be remembered and other words to be processed. Those to-be-remembered words that had a high degree of overlap with the processed words were recalled worse, lending some support to the idea of interference through feature overwriting.
37.6.3.Time-based resource sharing model
The theory most successful so far in explaining experimental data on the interaction of maintenance and processing in working memory is the "time-based resource sharing model”. This theory assumes that representations in working memory decay unless they are refreshed. Refreshing them requires an intentional mechanism that is also needed for any concurrent processing task. When there are small time intervals in which the processing task does not require attention, this time can be used to refresh memory traces. The theory therefore predicts that the amount of forgetting depends on the temporal density of intentional demands of the processing task - this density is called "cognitive load". The cognitive load depends on two variables, the rate at which the processing task requires individual steps to be carried out, and the duration of each step. For example, if the processing task consists of adding digits, then having to add another digit every half second places a higher cognitive load on the system than having to add another digit every two seconds. Adding larger digits takes more time than adding smaller digits, and therefore cognitive load is higher when larger digits must be added. In a series of experiments, Barrouillet and colleagues have shown that memory for lists of letters depends on cognitive load, but not on the number of processing steps (a finding that is difficult to explain by an interference hypothesis) and not on the total time of processing (a finding difficult to explain by a simple decay hypothesis). One difficulty for the time-based resource-sharing model, however, is that the similarity between memory materials and materials processed also affects memory accuracy.
37.6.4.Training of working memory
One theory of attention-deficit hyperactivity disorder states that ADHD can lead to deficits in working memory. Recent studies suggest that working memory can be improved by training in ADHD patients through the Cog med computerized program developed by Torkel Klingberg and his colleagues at the Karolinska Institute in Sweden. This random controlled study has found that a period of working memory training increases a range of cognitive abilities and increases IQ test scores. Consequently, this study supports previous findings suggesting that working memory underlies general intelligence. Another study of the same group has shown that, after training, measured brain activity related to working memory increased in the prefrontal cortex, an area that many researchers have associated with working memory functions. It has been shown that working memory training leads to measurable density changes for cortical dopamine neuroreceptors in test persons. A controversial study has shown that training with a working memory task (the dual n-back task) improves performance on a very specific fluid intelligence test in healthy young adults. The study's conclusion that improving or augmenting the brain's working memory ability increases fluid intelligence is backed by some and questioned by others. In Torkel Klingberg’s 2009 book The Overflowing Brain, he proposes that working memory is enhanced through exposure to excess neural activation. The brain map of an individual, he argues, can be altered by this activation to create a larger area of the brain activated by a particular type of sensory experience. An example would be that in learning to play guitar, the area activated by sensory impressions of the instrument is larger in the brain of a player than it is in a nonpayer.
37.7.0.Working memory in the brain
The first insights into the neuronal basis of working memory came from animal research. Fuster recorded the electrical activity of neurons in the prefrontal cortex (PFC) of monkeys while they were doing a delayed matching task. In that task, the monkey sees how the experimenter places a bit of food under one of two identical looking cups. A shutter is then lowered for a variable delay period, screening off the cups from the monkey’s view. After the delay, the shutter opens and the monkey is allowed to retrieve the food from under the cups. Successful retrieval in the first attempt – something the animal can achieve after some training on the task – requires holding the location of the food in memory over the delay period. Fuster found neurons in the PFC that fired mostly during the delay period, suggesting that they were involved in representing the food location while it was invisible. Later research has shown similar delay-active neurons also in the posterior parietal cortex, the thalamus, the caudate, and the globus pallidus.
Localization of brain functions in humans has become much easier with the advent of brain imaging methods (PET and fMRI). This research has confirmed that areas in the PFC are involved in working memory functions. During the 1990s much debate has centered on the different functions of the ventrolateral (i.e., lower areas) and the dorsolateral (higher) areas of the PFC. One view was that the dorsolateral areas are responsible for spatial working memory and the ventrolateral areas for non-spatial working memory. Another view proposed a functional distinction, arguing that ventrolateral areas are mostly involved in pure maintenance of information, whereas dorsolateral areas are more involved in tasks requiring some processing of the memorized material. The debate is not entirely resolved but most of the evidence supports the functional distinction. Brain imaging has also revealed that working memory functions are by far not limited to the PFC. A review of numerous studies shows areas of activation during working memory tasks scattered over a large part of the cortex. There is a tendency for spatial tasks to recruit more right-hemisphere areas, and for verbal and object working memory to recruit more left-hemisphere areas. The activation during verbal working memory tasks can be broken down into one component reflecting maintenance, in the left posterior parietal cortex, and a component reflecting subvocal rehearsal, in the left frontal cortex (Broca’s area, known to be involved in speech production) There is an emerging consensus that most working memory tasks recruit a network of PFC and parietal areas. A study has shown that during a working memory task the connectivity between these areas increases. Another study has demonstrated that these areas are necessary for working memory, and not simply activated accidentally during working memory tasks, by temporarily blocking them through transcranial magnetic stimulation (TMS), thereby producing an impairment in task performance.
37.7.3.Functions of different areas
A current debate concerns the function of these brain areas. The PFC has been found to be active in a variety of tasks that require executive functions. This has led some researchers to argue that the role of PFC in working memory is in controlling attention, selecting strategies, and manipulating information in working memory, but not in maintenance of information. The maintenance function is attributed to more posterior areas of the brain, including the parietal cortex. Other authors interpret the activity in parietal cortex as reflecting executive functions, because the same area is also activated in other tasks requiring executive attention but no memory
Most brain imaging studies of working memory have used recognition tasks such as delayed recognition of one or several stimuli, or the n-back task, in which each new stimulus in a long series must be compared to the one presented n steps back in the series. The advantage of recognition tasks is that they require minimal movement (just pressing one of two keys), making fixation of the head in the scanner easier. Experimental research and research on individual differences in working memory, however, has used largely recall tasks (e.g., the reading span task, see below). It is not clear to what degree recognition and recall tasks reflect the same processes and the same capacity limitations. A few brain imaging studies have been conducted with the reading span task or related tasks. Increased activation during these tasks was found in the PFC and, in several studies, also in the anterior cingulated cortex (ACC). People performing better on the task showed larger increase of activation in these areas, and their activation was correlated more over time, suggesting that their neural activity in these two areas was better coordinated, possibly due to stronger connectivity.
37.7.5.Effects of stress
Working memory is impaired by acute psychological stress. fMRI research finds that reduced working memory caused by accute stress links to reduced activation of the prefrontal cortex. This effect could link to the effects upon the prefrontal cortex of stress increased levels of catecholamines.
37.7.6.Neural maintenance of working memories
Much has been learned over the last two decades on where in the brain working memory functions are carried out. Much less is known on how the brain accomplishes short-term maintenance and goal-directed manipulation of information. The persistent firing of certain neurons in the delay period of working memory tasks shows that the brain has a mechanism of keeping representations active without external input. Keeping representations active, however, is not enough if the task demands maintaining more than one chunk of information. In addition, the components and features of each chunk must be bound together to prevent them from being mixed up. For example, if a red triangle and a green square must be remembered at the same time, one must make sure that “red” is bound to “triangle” and “green” is bound to “square”. One way of establishing such bindings is by having the neurons that represent features of the same chunk fire in synchrony, and those that represent features belonging to different chunks fire out of sync. In the example, neurons representing redness would fire in synchrony with neurons representing the triangular shape, but out of sync with those representing the square shape. So far, there is no direct evidence that working memory uses this binding mechanism, and other mechanisms have been proposed as well. It has been speculated that synchronous firing of neurons involved in working memory oscillate with frequencies in the theta band (4 to 8 Hz). Indeed, the power of theta frequency in the EEG increases with working memory load, and oscillations in the theta band measured over different parts of the skull become more coordinated when the person tries to remember the binding between two components of information.
38.0.Working memory and learning
There is now extensive evidence that working memory is linked to key learning outcomes in literacy and numeracy. In a recent large-scale screening study, one in ten children in mainstream classrooms were identified with working memory deficits. The majority of them performed very poorly in academic achievements, independent of their IQ. Without appropriate intervention, these children lag behind their peers. Recent research has also confirmed that working memory capacity, but not IQ, predicts learning outcomes two years later. This suggests that working memory impairments are associated with low learning outcomes and constitute a high risk factor for educational under achievement for children. In children with learning disabilities such as dyslexia, ADHD, and developmental coordination disorder, a similar pattern is evident. In a classroom, common characteristics of working memory impairment include a failure to remember instructions and an inability to complete learning activities. Without early diagnosis, working memory impairment negatively impacts a child’s performance throughout their scholastic career.
38.1.Working memory and attention
Research suggests a close link between the working memory capacities of a person and their ability to control the information from the environment that they can selectively enhance or ignore. Such attention allows for example for the voluntarily shifting in regard to goals of a person's information processing to spatial locations or objects rather than ones that capture their attention due to their sensory saliency (such as an ambulance siren). The goal directing of attention is driven by “top-down” signals from the prefrontal cortex that bias processing in posterior cortical areas and saliency capture by “bottom-up” control from sub cortical structures and the primary sensory cortices. The ability to override sensory capture of attention differs greatly between individuals and this difference closely links to their working memory capacity. The greater a person's working memory capacity, the greater their ability to resist sensory capture. The limited ability to override attentional capture is likely to result in the unnecessary storage of information in working memory, suggesting not only that having a poor working memory affects attention but that it can also limit the capacity of working memory even further.
Today there are hundreds of research laboratories around the world studying various aspects of working memory There are numerous applications of working memory in the field, such as using working memory capacity to explain intelligence, success at emotion regulation, and other cognitive abilities, furthering the understanding of autism, ADHD, motor dyspraxia, and improving teaching methods, , and creating artificial intelligence based on the human brain.
38.2.1.Amnesia (from Greek Ἀμνησία) is a memory condition in which memory is disturbed. In simple terms it is the loss of memory. The causes of amnesia are organic or functional. Organic causes include damage to the brain, through trauma or disease, or use of certain (generally sedative) drugs. Functional causes are psychological factors, such as defense mechanisms. Hysterical post-traumatic amnesia is an example of this. Amnesia may also be spontaneous, in the case of transient global amnesia. This global type of amnesia is more common in middle-aged to elderly people, particularly males, and usually lasts less than 24 hours. Another effect of amnesia is the inability to imagine the future. A recent study published online in the Proceedings of the National Academy of Sciences shows that amnesiacs with damaged hippocampus cannot imagine the future. This is because a normal human being, imagining the future, uses past experiences to construct a possible scenario. For example, a person trying to imagine what would happen at a party set to occur in the near future would use past experience at parties to help construct the event.
38.3.0.Forms of amnesia
38.3.1. In anterograde amnesia, new events contained in the immediate memory are not transferred to the permanent as long-term memory.
38.3.2.Retrograde amnesia is the distinct inability to recall some memory or memories of the past, beyond ordinary forgetfulness.
The terms are used to categorize patterns of symptoms, rather than to indicate a particular cause or etiology. Both categories of amnesia can occur together in the same patient, and commonly result from drug effects or damage to the brain regions most closely associated with episodic/declarative memory: the medial temporal lobes and especially the hippocampus.
An example of mixed retrograde and anterograde amnesia may be a motorcyclist unable to recall driving his motorbike prior to his head injury (retrograde amnesia), nor can he recall the hospital ward where he is told he had conversations with family over the next two days (anterograde amnesia). The effects of amnesia can last long after the condition has passed; many sufferers claim that amnesia changes from a neurological condition to a psychological condition, whereby the patient loses confidence and faith in their own memory and accounts of past events.
38.4.0.Types and causes of amnesia
38.4.1.Post-traumatic amnesia is generally due to a head injury (e.g. a fall, a knock on the head). Traumatic amnesia is often transient, but may be permanent of either anterograde, retrograde, or mixed type. The extent of the period covered by the amnesia is related to the degree of injury and may give an indication of the prognosis for recovery of other functions. Mild trauma, such as a car accident that results in no more than mild whiplash, might cause the occupant of a car to have no memory of the moments just before the accident due to a brief interruption in the short/long-term memory transfer mechanism. The sufferer may also lose knowledge of who people are, they may remember events, but will not remember faces of them.
38.4.2.Dissociative amnesia results from a psychological cause as opposed to direct damage to the brain caused by head injury, physical trauma or disease, which is known as organic amnesia. Dissociative amnesia can include:
38.4.3.Repressed memory refers to the inability to recall information, usually about stressful or traumatic events in persons' lives, such as a violent attack or rape. The memory is stored in long term memory, but access to it is impaired because of psychological defense mechanisms. Persons retain the capacity to learn new information and there may be some later partial or complete recovery of memory. This contrasts with e.g. anterograde amnesia caused by amnestics such as benzodiazepines or alcohol, where an experience was prevented from being transferred from temporary to permanent memory storage: it will never be recovered, because it was never stored in the first place. Formerly known as "Psychogenic Amnesia"
38.4.4.Dissociative Fugue (formerly Psychogenic Fugue) is also known as fugue state. It is caused by psychological trauma and is usually temporary, unresolved and therefore may return. The Merck Manual defines it as "one or more episodes of amnesia in which the inability to recall some or all of one's past and either the loss of one's identity or the formation of a new identity occur with sudden, unexpected, purposeful travel away from home." While popular in fiction, it is extremely rare.
38.4.5.Posthypnotic amnesia is where events during hypnosis are forgotten, or where past memories are unable to be recalled.
38.5.5.Lacunar amnesia is the loss of memory about one specific event.
38.5.6.Childhood amnesia (also known as infantile amnesia) is the common inability to remember events from one's own childhood. Sigmund Freud attributed this to sexual repression, while others have theorised that this may be due to language development or immature parts of the brain.
38.5.7.Transient global amnesia is a well-described medical and clinical phenomenon. This form of amnesia is distinct in that abnormalities in the hippocampus can sometimes be visualized using a special form of magnetic resonance imaging of the brain known as diffusion-weighted imaging (DWI). Symptoms typically last for less than a day and there is often no clear precipitating factor nor any other neurological deficits. The cause of this syndrome is not clear, hypotheses include transient reduced blood flow, possible seizure or an atypical type of migraine. Patients are typically amnestic of events more than a few minutes in the past, though immediate recall is usually preserved.
38.5.8.Source amnesia is a memory disorder in which someone can recall certain information, but they do not know where or how they obtained the information.
38.5.9.Memory distrust syndrome is a term invented by the psychologist Gisli Gudjonsson to describe a situation where someone is unable to trust their own memory.
38.5.10.Blackout phenomenon can be caused by excessive short-term alcohol consumption, with the amnesia being of the anterograde type.
38.5.11.Korsakoff's syndrome can result from long-term alcoholism or malnutrition. It is caused by brain damage due to a Vitamin B1 deficiency and will be progressive if alcohol intake and nutrition pattern are not modified. Other neurological problems are likely to be present in combination with this type of Amnesia. Korsakoff's syndrome is also known to be connected with confabulation.
38.5.12.Drug-induced amnesia is intentionally caused by injection of an amnesiac drug to help a patient forget surgery or medical procedures, particularly those which are not performed under full anesthesia, or which are likely to be particularly traumatic. Such drugs are also referred to as "premedicants". Most commonly a 2'-halogenated benzodiazepine such as midazolam or flunitrazepam is the drug of choice, although other strongly amnestic drugs such as propofol or scopolamine may also be used for this application. Memories of the short time frame in which the procedure was performed are permanently lost or at least substantially reduced, but once the drug wears off, memory is no longer affected.
38.5.13.Prosopamnesia is the inability to remember faces, even in the presence of intact facial recognition capabilities. Both acquired and inborn cases have been documented.
38.5.14.Situation-Specific amnesia can arise in a variety of circumstances (e.g., commiting an offence, child sexual abuse) resulting in PTSD. It has been claimed that it involves a narrowing of consciousness with attention focused on central perceptual details and/or that the emotional or traumatic events are processed differently from ordinary memories.
39.0.Amnesia in popular culture
Global amnesia is a common motif in fiction despite being extraordinarily rare in reality. In the introduction to his anthology The Vintage Book of Amnesia, Jonathan Lethem writes:
Real, diagnosable amnesia – people getting knocked on the head and forgetting their names – is mostly just a rumor in the world. It's a rare condition, and usually a brief one. In books and movie, though, versions of amnesia lurk everywhere, from episodes of Mission Impossible to metafictional and absurdist masterpieces, with dozens of stops in between. Amnesiacs might not much exist, but amnesiac characters stumble everywhere through comic books, movies, and our dreams. We've all met them and been them.
Lethem traces the roots of literary amnesia to Franz Kafka and Samuel Beckett, among others, fueled in large part by the seeping into popular culture of the work of Sigmund Freud, which also strongly influenced genre films such as film noir. Amnesia is so often used as a plot device in films, that a widely-recognized sterotypical dialogue has even developed around it, with the victim melodramatically asking "Where am I? Who am I? What am I?", or sometimes inquiring of his own name, "Bill? Who's Bill?"
In movies and television, particularly sitcoms and soap operas, it is often depicted that a second blow to the head, similar to the first one which caused the amnesia, will then cure it. In reality, however, repeat concussions may cause cumulative deficits including cognitive problems, and in extremely rare cases may even cause deadly swelling of the brain associated with second-impact syndrome.
Amnesia has also been useful as a plot device in many video games, to help explain why the main character, and therefore the player, knows very little about the world he is in.
The concept was originated by Sigmund Freud in his 1896 essay Zur Ätiologie der Hysterie ("On the etiology of hysteria Freud abandoned his theory between 1897 and 1905, replacing it during 1920-1923 with his impulse-based concept of Ego, super-ego, and id. Friedrich Nietzsche was the first to suggest an active, conscious thought management method in the second essay of his On the Genealogy of Morals as a necessary fundament of efficiency, responsibility, and maturity.
Some research indicates that memories of child sexual abuse and other traumatic incidents may be forgotten. Evidence of the spontaneous recovery of traumatic memories has been shown, and recovered memories of traumatic childhood abuse have been corroborated. Van der Kolk and Fisler's research shows that traumatic memories are retrieved, at least at first, in the form of mental imprints that are dissociated. These imprints are of the affective and sensory elements of the traumatic experience. Clients have reported the slow emergence of a personal narrative that can be considered explicit (conscious) memory. The level of emotional significance of a memory correlates directly with the memory's veracity. Studies of subjective reports of memory show that memories of highly significant events are unusually accurate and stable over time. The imprints of traumatic experiences appear to be qualitatively different from those of nontraumatic events. Traumatic memories may be coded differently than ordinary event memories, possibly because of alterations in attentional focusing or the fact that extreme emotional arousal interferes with the memory functions of the hippocampus. Although research on repressed memory is limited, a few studies have suggested that memories of trauma that are forgotten and later recalled have a similar accuracy rate as trauma memories that had not been forgotten. There has also been significant questioning of the reality of repressed memories. There is considerable evidence that rather than being pushed out of consciousness, the difficulty with traumatic memories for most people are their intrusiveness and inability to forget. One case that is held up as definitive proof of the reality of repressed memories, recorded by David Corwin has been criticized by Elizabeth Loftus and Melvin Guyer for ignoring the context of the original complaint and falsely presenting the sexual abuse as unequivocal and true when in reality there was no definitive proof.
It has been speculated that repression may be one method used by individuals to cope with traumatic memories, by pushing them out of awareness (perhaps as an adaptation via psychogenic amnesia) to allow a child to maintain attachment to a person on whom they are dependent for survival. Researchers have proposed that repression can operate on a social level as well.
The existence of repressed memory recovery has not been completely accepted by mainstream psychology, nor unequivocally proven to exist, and some experts in the field of human memory feel that no credible scientific support exists for the notions of repressed/recovered memories. One research report states that a distinction should be made between spontaneously recovered memories and memories recovered during suggestions in therapy.
Some criminal cases have been based on a witness' testimony of recovered repressed memories, often of alleged childhood sexual abuse. In some jurisdictions, the statute of limitations for child abuse cases has been extended to accommodate the phenomena of repressed memories as well as other factors. The repressed memory concept came into wider public awareness in the 1980s and 1990s followed by a reduction of public attention after a series of scandals, lawsuits, and license revocations. In a 1996 ruling, a US District Court allowed repressed memories entered into evidence in court cases. Jennifer Freyd writes that Ross Cheit's case of suddenly remembered sexual abuse is one of the most well-documented cases available for the public to see. Cheit prevailed in two lawsuits, located five additional victims and tape-recorded a confession. On 16 December 2005 the Irish Court of Criminal Appeal issued a certificate confirming a Miscarriage of Justice to a former nun Nora Wall whose 1999 conviction for child rape was partly based on Repressed Memory evidence. The judgement stated that: "There was no scientific evidence of any sort adduced to explain the phenomenon of ‘flashbacks’ and/or ‘retrieved memory’, nor was the applicant in any position to meet such a case in the absence of prior notification thereof."
40.0. Motivation and Emotion
Ever wonder why some people seem to be very successful, highly motivated individuals? Where does the energy, the drive, or the direction come from? Motivation is an area of psychology that has gotten a great deal of attention, especially in the recent years. The reason is because we all want to be successful, we all want direction and drive, and we all want to be seen as motivated.
There are several distinct theories of motivation; Some include basic biological forces, while others seem to transcend concrete explanation. I will focus on the five major theories of motivation.
Instinct theory is derived from our biological make-up. We've all seen spider's webs and perhaps even witnessed a spider in the tedious job of creating its home and trap. We've all seen birds in their nests, feeding their young or painstakingly placing the twigs in place to form their new home. How do spiders know how to spin webs? How do birds now how to build nests? The answer is biology. All creatures are born with specific innate knowledge about how to survive. Animals are born with the capacity and often times knowledge of how to survive by spinning webs, building nests, avoiding danger, and reproducing. These innate tendencies are preprogrammed at birth, they are in our genes, and even if the spider never saw a web before, never witnessed its creation, it would still know how to create one.
Humans have the same types of innate tendencies. Babies are born with a unique ability that allows them to survive; they are born with the ability to cry. Without this, how would others know when to feed the baby, know when he needed changing, or when she wanted attention and affection? Crying allows a human infant to survive. We are also born with particular reflexes which promote survival. The most important of these include sucking, swallowing, coughing, blinking. Newborns can perform physical movements to avoid pain; they will turn their head if touched on their cheek and search for a nipple (rooting reflex); and they will grasp an object that touches the palm of their hands.
40.3.Drive Reduction Theory
According to Clark Hull (1943, 1952), humans have internal internal biological needs which motivate us to perform a certain way. These needs, or drives, are defined by Hull as internal states of arousal or tension which must be reduced. A prime example would be the internal feelings of hunger or thirst, which motivates us to eat. According to this theory, we are driven to reduce these drives so that we may maintain a sense of internal calmness.
Similar to Hull's Drive Reduction Theory, Arousal theory states that we are driven to maintain a certain level of arousal in order to feel comfortable. Arousal refers to a state of emotional, intellectual, and physical activity. It is different from the above theory, however, because it doesn't rely on only a reduction of tension, but a balanced amount. It also does better to explain why people climb mountains, go to school, or watch sad movies.
Remember Sigmund Freud and his five part theory of personality. As part of this theory, he believed that humans have only two basic drives: Eros and Thanatos, or the Life and Death drives. According to Psychoanalytic theory, everything we do, every thought we have, and every emotion we experience has one of two goals: to help us survive or to prevent our destruction. This is similar to instinct theory, however, Freud believed that the vast majority of our knowledge about these drives is buried in the unconscious part of the mind.
Psychoanalytic theory therefore argues that we go to school because it will help assure our survival in terms of improved finances, more money for healthcare, or even an improved ability to find a spouse. We move to better school districts to improve our children's ability to survive and continue our family tree. We demand safety in our cars, toys, and in our homes. We want criminal locked away, and we want to be protected against poisons, terrorists, and anything else that could lead to our destruction. According to this theory, everything we do, everything we are can be traced back to the two basic drives
40.6. Humanistic Theory
Although discussed last, humanistic theory is perhaps the most well know theory of motivation. According to this theory, humans are driven to achieve their maximum potential and will always do so unless obstacles are placed in their way. These obstacles include hunger, thirst, financial problems, safety issues, or anything else that takes our focus away from maximum psychological growth. The best way to describe this theory is to utilize the famous pyramid developed by Abraham Maslow (1970) called the Hierarchy of Needs. Maslow believed that humans have specific needs that must be met and that if lower level needs go unmet, we can not possible strive for higher level needs. The Hierarchy of Needs shows that at the lower level, we must focus on basic issues such as food, sleep, and safety. Without food, without sleep, how could we possible focus on the higher level needs such as respect, education, and recognition?
Throughout our lives, we work toward achieving the top of the pyramid, self actualization, or the realization of all of our potential. As we move up the pyramid, however, things get in the way which slow us down and often knock us backward. Imagine working toward the respect and recognition of your colleagues and suddenly finding yourself out of work and homeless. Suddenly, you are forced backward and can no longer focus your attention on your work due to the need for finding food and shelter for you and your family.
According to Maslow, nobody has ever reached the peak of his pyramid. We all may strive for it and some may even get close, but no one has achieved full self-actualization. Self-actualization means a complete understanding of who you are, a sense of completeness, of being the best person you could possibly be. To have achieved this goal is to stop living, for what is there to strive for if you have learned everything about yourself, if you have experienced all that you can, and if there is no way left for you to grow emotionally, intellectually, or spiritually.
Everybody has heard of peer pressure, but most people argue that they are not affected by it, or at least not affected as 'most people.' The truth is, we are all affected by the people we interact with, many of whom we don't even know personally. Our social environments play a significant role in how we view ourselves, and conversely, how we see ourselves impacts our view of the world.
41.1.Our View of Self and Others
The way we look at ourselves plays an important role in how we see the world. The way we see the world plays an important role in how we see ourselves. In this sense, our view of self and others is an ever-changing circle of influence. We know that those who are happy see more positive aspects of the world than those who are depressed. We also know that living in an abusive household or an overly restrictive environment can both lead to depression. This section will explore the social areas of attribution (how we interpret those around us) and attraction (what we seek in a friend or partner).
We tend to explain our own behavior and the behavior of others by assigning attributes to these behavior. An attribute is an inference about the cause of a behavior. According to the Attribution Theory, we tend to explain our own behavior and the behavior of others by assigning attributes to these behavior.
There are basically two sources for our behavior; those influenced by Situational (external) factors and those influenced by Dispositional (internal) factors. Imagine walking into your boss's office and he immediately tells you, in an angry tone, not to bother him. An external explanation of this behavior might be, "He's really a nice guy but the stress is overwhelming. He needs a vacation." On the other hand, you might see the same behavior and say, "What a jerk, I don't know why is is so angry all the time." The same behavior is given two very opposite explanations.
Many factors play a role in how we assign attributes to behaviors. Obviously our view of the world, our previous experience with a particular person or situation, and our knowledge of the behavior play an important role. Other factors can influence our interpretation as well, and there are two important errors or mistakes we tend make when assigning these attributes.
41.2.0. Fundamental Attribution Error. This refers to the tendency to over estimate the internal and underestimate the external factors when explaining the behaviors of others. This may be a result of our tendency to pay more attention to the situation rather than to the individual (Heider, 1958) and is especially true when we know little about the other person. For example, the last time you were driving and got cut off did you say to yourself "What an idiot" (or something similar), or did you say "She must be having a rough day." Chances are that this behavior was assigned mostly internal attributes and you didn't give a second thought to what external factors are playing a role in her driving behavior.
41.2.2. Self-Serving Bias. We tend to equate successes to internal and failures to external attributes (Miller & Ross, 1975). Imagine getting a promotion. Most of us will feel that this success is due to hard work, intelligence, dedication, and similar internal factors. But if you are fired, well obviously your boss wouldn't know a good thing if it were staring her in the face. This bias is true for most people, but for those who are depressed, have low self-esteem, or view themselves negatively, the bias is typically opposite. For these people, a success may mean that a multitude of negatives have been overlooked or that luck was the primary reason. For failures, the depressed individual will likely see their own negative qualities, such as stupidity, as being the primary factor.
Why are we attracted to certain people and not others? Why do our friends tend to be very similar to each other? And what causes us to decide on a mate? Many of these questions relate to social psychology in that society's influence and our own beliefs and traits play an important role. Research has found five reasons why we choose our friends.:
42.1.Proximity - The vast majority of our friends live close to where we live, or at least where we lived during the time period the friendship developed (Nahemow & Lawton, 1975). Obviously friendships develop after getting to know someone, and this closeness provides the easiest way to accomplish this goal. Having assigned seats in a class or group setting would result in more friends who's last name started with the same letter as yours (Segal, 1974).
42.2.Association - We tend to associate our opinions about other people with our current state. In other words, if you meet someone during a class you really enjoy, they may get more 'likeability points' then if you met them during that class you can't stand.
42.3.Similarity - On the other hand, imagine that person above agrees with you this particular class is the worse they have taken. The agreement or similarity between the two of you would likely result in more attractiveness (Neimeyer & Mitchell, 1988)
42.4.Reciprocal Liking - Simply put, we tend to like those better who also like us back. This may be a result of the feeling we get about ourselves knowing that we are likable. When we feel good when we are around somebody, we tend to report a higher level of attraction toward that person (Forgas, 1992; Zajonc & McIntosh, 1992)
42.5.Physical Attractiveness - Physical attraction plays a role in who we choose as friends, although not as much so as in who we choose as a mate. Nonetheless, we tend to choose people who we believe to be attractive and who are close to how we see our own physical attractiveness.
This last statement brings up an important factor in how we determine our friends and partner. Ever wonder why very attractive people tend to 'hang around' other very attractive people? Or why wealthy men seem to end up with physically attractive, perhaps even much younger, women? There is some truth to these stereotypical scenarios because we tend to assign "social assets" or "attraction points" to everyone we meet.
These points are divided into categories such as physical attractiveness, sense of humor, education, and wealth. If we view education as very important, we may assign more points to this category making it more likely that our friends or our mate will have more education. If we view wealth as more important then we will be more likely to find a mate who has more money.
We rate ourselves on these same categories and, at least at some level, know our score. We tend to then pick friends and partners who have a similar score that we do. Hence an attractive person hangs with other attractive people; or a wealthy older man gets the beautiful younger woman. Think about your friends and how you would rate them in these categories to find out what is important to you.
43.0.Obedience and Power
Why do we obey some people and not others? Why are you able to influence your friends? What attributes cause a person to be more influential? These questions are paramount in understanding social order. The answers to these questions also play an important role in many professions, such as sales and marketing and of course politics.
43.1. What 'power' is, Power is typically thought of has having a certain attribute which gives one person more influence over another. This attribute could be intelligence or experience; it could be job title, or perhaps money. According to most social psychologists, there are five types of power: coercive, reward, legitimate, expert, and referent.
43.1.0. Coercive power means the power punish. Parents are said to have coercive power because they can place their child in time-out, for example; bosses have coercive power because they can fire an employee or assign an employee a less pleasing job. Reward power is almost the opposite; it is the power to reward. In that sense parents and bosses have this type of power as well, as do many others in our lives. Legitimate power refers to the power granted by some authority, such as the power a police officer has due to the local or state government or the power a professor has due to the rules of a college or university.
43.1.1.Expert power results from experience or education. Those individuals with more knowledge tend to have more power in situations where that knowledge is important. For instance, the physician will have more power in a medical emergency than the plumber. But, when the pipes explode and the house is being flooded, the physician is not the person to call. Finally, referent power refers to admiration or respect. When we look up to people because of their accomplishments, their attitude, or any other personal attribute, we tend to give them more power over us. Imagine being asked to do something by your "hero" or your favorite movie star; we are very likely to comply out of admiration or respect.
43.2.Using Power to Influence Others
Now that we know what power is and how people get it, lets talk about how this power is used to influence others. Most of us know that liking and agreeing tend to go together. We agree with our friends about many issues, especially the bigger ones, and often disagree with our opponents. Also, beliefs and behaviors tend to go together. For instance, most people who believe stealing is very immoral would not steal, most who believe littering is wrong, do not litter. What's interesting about this latter concept is what happens when our belief and our behavior do not correspond. You might think that we would change the way we act, but in the real world, we tend to change our belief about a topic before we would change our behavior. The person who believes littering is wrong, after throwing a soda can from their car window, might say to himself, "It was only one time," or "look at all the other trash on the freeway." in this sense, his belief has changed; littering is now okay if it is only done once or if others have littered first. To equate this with influencing others, we see that if we can change the way a person behaves, we can change the way they think or feel. Imagine the car salesman who is able to convince the potential buyer that this new car is the one he wants to buy. The sales man might try to use many different techniques, but one is the 'test drive.' The theory behind this is that if the person's actions include driving the car, they are more likely to change their belief about the car. There are other variables associated with influencing others or attitude change. Lets take a look first at what attributes the source or the talker help her influence others. First of all is power, as discussed above. The more types of power and the stronger each of these is, the more influential she will be. Second, a person must be believable in order to influence us. The source must therefore be trustworthy, after all, if we don't believe someone, they're going to have a much more difficult time changing our minds. Finally, attractiveness plays a role in how influence us. We tend to be influenced more by attractive people, including physical and social attractiveness, likeability, demeanor, and dress.
The target or listener plays a role in how he will be influenced as well. Those with low self-esteem and/or high self-doubt tend to be more influenced that others. The more we doubt our own ability, the more we look to others for guidance or input. Other factors such as age, IQ, gender, or social status do not appear to play a significant role in how we are influenced by others. Finally, lets look at the relationship between the source and the target. First of all, there needs to be some similarity between the two people. If the target or listener does not feel any similarity with the talker, he is much less likely to accept what she is saying. After all, we have nothing in common so what could she possible know about my life. The more similar the two, the greater the influential ability. Second, there needs to be a moderate discrepancy in attitude. If the difference between the two is too large, changing the listener's attitude or belief will be too difficult. If the difference is too small, then no significant change will take place at all. The difference must be great enough that a change is possible but small enough that the listener is open to the change.
44.0.The Role of Groups
Do you think you act differently when alone than when other people are around? The answer to this question is typically a resounding 'yes.' We are concerned with our social image or how other people see us; some more than others, but very few people see no difference in their behavior. This section will discuss various theories relating to our behavior in group settings or when others are present.
Let’s look at this simple theory related to social psychology. When alone, we tend to be more relaxed, less concerned with the outward expression of our behavior, and are basically 'ourselves.' Add just one other person, even if we don't know that person, our behavior tends to change, and not always for the better. Research has found that when others are present, our level of arousal is increased (Zajonc, 1965). In other words, we are suddenly more aware of what's going on around us. Because of this, we tend to perform better at tasks that are well learned or simple (Guerin, 1993). When completing a difficult or new task, however, our performance level decreases and we tend to do more poorly.
This phenomenon is called Social Facilitation (Guerin, 1993) , and as we try harder due to the presence of others, our performance actually decreases for difficult or unlearned tasks. Think about learning to play basketball for the first time. If you are alone, you will likely be more relaxed, and better able to concentrate. When others are watching you, however, you are more likely to be self-conscious, and therefore make more mistakes. Professional basketball players, however, because the task is so well learned, perform better when others are watching and they are able demonstrate their confidence and ability.
44.2.Group Think and Group Polarization
If you've ever been involved in a group decision making process, you've probably seen one of two things happen: either the group agrees on all of the major issues, or there is significant dissent that splits the group. If the group is cohesive; if they agree on most issues, they tend to stifle dissent because group harmony is the anticipated outcome (Janis, 1972). When we all agree, and are happy with that agreement, we typically do not want to hear opposing arguments. This phenomenon is referred to as Group Think. It can lead to impulsive decisions and a failure to identify and/or consider all sides of an argument. Some classic examples of group decisions going bad include lynch mobs, actions of the Ku Klux Klan, discrimination among hate groups, and mass riots.
Similar to this, Group Polarization refers to a groups tendency to talk itself into extreme
positions. In this case, a group gets so focused and energized about a decision that it creates an internal fuel, so to speak, which pushes itself forward faster than originally intended. Imagine a group of protesters, all agreeing and deciding to picket. You can see how this could get out of hand because opposing views (Group Think) are not considered and the push to move forward for the cause is fueled internally (Group Polarization).
Another phenomenon that occurs in groups is referred to as Social Loafing. This theory states that as a group gets larger, the individual contribution decreases disproportionate to the group size (Everett, Smith, & Williams, 1992; Hardy & Latane, 1986; Ingham et al., 1974) . This is due to the diffusion of responsibility created as the size of the group increases. Imagine being assigned a project to complete by yourself. Most likely you would complete 100% of it. Now if two people are involved, the percentage will typically not be 50/50. As more people are added to the group, you will end up with a small percentage doing a large portion of the work and a large percentage doing a much smaller proportion.
This last phenomenon is an unfortunate reality which has been observed far to many times in groups and in larger cities. We've all heard stories of people getting mugged, or beaten, or raped in broad daylight while people around offered no assistance. We have found that the internal push to help a person in need decreases as the group gets larger, very similar to Social Loafing. In this instance, however, people tend to be followers and will only get involved if they witness another person getting involved. What results is a group of people witnessing a crime and wondering why nobody is helping. This does not occur if you are the only person witnessing the crime. If nobody else is around, a person will tend to help the victim. The more people, however, the less likely someone will offer assistance.
45.0.Branches of Psychology
Psychology is an extremely broad field, encompassing many different approaches to the study of mental processes and behavior. Below are the major areas of inquiry that comprise psychology, divided into fields of research psychology and fields of applied psychology. A comprehensive list of the sub-fields and areas within psychology can be found at the list of psychological topics and list of psychology disciplines.
The study of psychology in philosophical context dates back to the ancient civilizations of Egypt, Greece, China, India, and Persia. Psychology began adopting a more clinical and experimental approach under medieval Muslim psychologists and physicians, who built psychiatric hospitals for such purposes. In 1802, French physiologist Pierre Cabanis helped to pioneer biological psychology with his essay Rapports du physique et du moral de l'homme (On the relations between the physical and moral aspects of man). Cabanis interpreted the mind in light of his previous studies of biology, arguing that sensibility and soul are properties of the nervous system.
Though the use of psychological experimentation dates back to Alhazen's Book of Optics in 1021, psychology as an independent experimental field of study began in 1879, when the German physician Wilhelm Wundt founded the first laboratory dedicated exclusively to psychological research at Leipzig University in Germany, for which Wundt is known as the "father of psychology". The year 1879 is thus sometimes regarded as the "birthdate" of psychology. The American philosopher and psychologist William James published his seminal book, Principles of Psychology in 1890, laying the foundations for many of the questions on which psychologists would focus for years to come. Other important early contributors to the field include the German psychologist Hermann Ebbinghaus (1850–1909), a pioneer in the experimental study of memory at the University of Berlin; and the Russian physiologist Ivan Pavlov (1849–1936) who investigated the learning process now referred to as classical conditioning.
Starting in the 1950s, the experimental techniques set forth by Wundt, James, Ebbinghaus, and others would be reiterated as experimental psychology became increasingly cognitive (concerned with information and its processing) and, eventually, constituted a part of the wider cognitive science. In its early years, however, this development was seen as a "revolution", as it both responded to and reacted against strains of thought—including psychodynamics and behaviorism—that had developed in the meantime.
From the 1890s until his death in 1939, the Austrian physician Sigmund Freud developed a method of psychotherapy known as psychoanalysis. Freud's understanding of the mind was largely based on interpretive methods, introspection and clinical observations, and was focused in particular on resolving unconscious conflict, mental distress and psychopathology. Freud's theories became very well-known, largely because they tackled subjects such as sexuality, repression, and the unconscious mind as general aspects of psychological development. These were largely considered taboo subjects at the time, and Freud provided a catalyst for them to be openly discussed in polite society. Clinically, he helped to pioneer the method of free association and a therapeutic interest in dreams.
Freud had a significant influence on Swiss psychiatrist Carl Jung, whose analytical psychology became an alternative form of depth psychology. Other well-known psychoanalytic thinkers of the mid-twentieth century included Sigmund Freud's daughter psychoanalyst Anna Freud, German-American psychologist Erik Erickson, Austrian-British psychoanalyst Melanie Klein, English psychoanalyst and physician D. W. Winnicott, German psychologist Karen Horney, German-born psychologist and philosopher Erich Fromm, and English psychiatrist John Bowlby. Throughout the 20th century, psychoanalysis evolved into diverse schools of thought, most of which may be classed as Neo-Freudian. Psychoanalytic theory and therapy were criticized by psychologists such as B. F. Skinner and Hans Eysenck, and by philosophers including Karl Popper. Skinner and other behaviorists believed that psychology should be more empirical and efficient than psychoanalysis, although they frequently agreed with Freud in ways that became overlooked as time passed. Popper, a philosopher of science, argued that Freud's, as well as Alfred Adler's, psychoanalytic theories included enough ad hoc safeguards against empirical contradiction that the theories fell outside the realm of scientific inquiry. By contrast, Eysenck maintained that although Freudian ideas could be subjected to experimental science, they had not withstood experimental tests. By the 21st century, psychology departments in American universities had become experimentally oriented, marginalizing Freudian theory and regarding it as a "desiccated and dead" historical artifact. Meanwhile, however, researchers in the emerging field of neuro-psychoanalysis defended some of Freud's ideas on scientific grounds, while scholars of the humanities maintained that Freud was not a "scientist at all, but ... an interpreter."
Founded in the early 20th century by American psychologist John B. Watson, behaviorism was embraced and extended by Americans Edward Thorndike, Clark L. Hull, Edward C. Tolman, and later B. F. Skinner. Behaviorism reflected a belief that the methodology behind laboratory-based animal experimentation, which was increasing in popularity as physiology grew more sophisticated, could provide useful psychosocial understanding of a type that comparatively subjective inquiries, such as psychodynamic analysis as employed by Freud or introspection as used by Wundt and James, could not.
The behaviorists shared with their predecessors a philosophical inclination toward positivism and determinism. With Skinner, however, they entered into a line of thought, extending back to Austrian physicist and philosopher Ernst Mach, which held that the research methods most faithful to their scientific orientation would yield "the pursuit of tools for the control of life problems rather than a search for timeless truths". The behaviorists argued that many contents of the mind were not open to scientific scrutiny and that scientific psychology should emphasize the study of observable behavior. Behaviorists focused on behavior-environment relations and analyzed overt and covert (i.e., private) behavior as a function of the organism interacting with its environment. Therefore, they often rejected or deemphasized dualistic explanations such as "mind" or "consciousness"; and, in lieu of probing an "unconscious mind" that underlies unawareness, they spoke of the "contingency-shaped behaviors" in which unawareness becomes outwardly manifest. Among the behaviorists' most famous creations are Watson's Little Albert experiment, which applied classical conditioning to a human being, and Skinner's notion of operant conditioning, which acknowledged that human agency could affect patterns and cycles of environmental stimuli and behavioral responses. American linguist Noam Chomsky's critique of the behaviorist model of language acquisition is regarded by many as a key factor in the decline of behaviorism's prominence. But Skinner's behaviorism has not died, perhaps in part because it has generated successful practical applications. The fall of behaviorism as an overarching model in psychology, however, gave way to a new dominant paradigm: cognitive approaches.
45.4.Humanism and existentialism
Humanistic psychology was developed in the 1950s in reaction to both behaviorism and psychoanalysis. By using phenomenology, intersubjectivity and first-person categories, the humanistic approach sought to glimpse the whole person—not just the fragmented parts of the personality or cognitive functioning. Humanism focused on fundamentally and uniquely human issues, such as self-identity, death, aloneness, freedom, and meaning. The humanistic approach was distinguished by its emphasis on subjective meaning, rejection of determinism, and concern for positive growth rather than pathology. Some of the founders of this school of thought were American psychologists Abraham Maslow, who formulated a hierarchy of human needs, and Carl Rogers, who created and developed client-centered therapy; and German-American psychiatrist Fritz Perls, who co-founded Gestalt therapy. It became so influential as to be called the "third force" within psychology, along with behaviorism and psychoanalysis. Later, positive psychology opened up humanistic themes to scientific modes of exploration.
Influenced largely by the work of German philosopher Martin Heidegger and Danish philosopher Søren Kierkegaard, psychoanalytically-trained American psychologist Rollo May pioneered an existential breed of psychology, which included existential therapy, in the 1950s and 1960s. Existential psychologists differed from others often classified as humanistic in their comparatively neutral view of human nature and in their relatively positive assessment of anxiety. Existential psychologists emphasized the humanistic themes of death, free will, and meaning, suggesting that meaning can be shaped by myths, or narrative patterns, and that it can be encouraged by an acceptance of the free will requisite to an authentic, albeit often anxious, regard for death and other future prospects. Austrian existential psychiatrist and Holocaust survivor Viktor Frankl drew evidence of meaning's therapeutic power from reflections garnered from his own internment, and he created a variety of existential psychotherapy called logotherapy. In addition to May and Frankl, Swiss psychoanalyst Ludwig Binswanger and American psychologist George Kelly may be said to belong to the existential school.
Noam Chomsky helped to ignite a "cognitive revolution" in psychology when he criticized the behaviorists' notions of "stimulus", "response", and "reinforcement", arguing that such ideas—which Skinner had borrowed from animal experiments in the laboratory—could be applied to complex human behavior, such as language acquisition, in only a vague and superficial manner. Chomsky emphasized that research and analysis must not ignore the innate contribution of the child to such behavior, while social learning theorists such as Albert Bandura argued that the child's environment could make contributions of its own to the behaviors of an observant subject. The notion that behavior could be precipitated only by the functioning of an internal device or by the perception of external surroundings posed a challenge to the behaviorist position that behavior is contingent upon the prior associations that individuals have made between behavioral responses and pleasurable or painful stimuli.
Meanwhile, accumulating technology helped to renew interest and belief in the mental states and representations i.e. the cognition that had fallen out of favor with behaviorists. English neuroscientist Charles Sherrington and Canadian psychologist Donald O. Herb used experimental methods to link psychological phenomena with the structure and function of the brain. With the rise of computer science and artificial intelligence, analogies were drawn between the processing of information by humans and information processing by machines. Research in cognition had proven practical since World War II, when it aided in the understanding of weapons operation. By the late 20th century, though, cognitivism had become the dominant paradigm of mainstream psychology, and cognitive psychology emerged as a popular branch.
Assuming both that the covert mind should be studied and that the scientific method should be used to study it, cognitive psychologists set such concepts as "subliminal processing" and "implicit memory" in place of the psychoanalytic "unconscious mind" or the behavioristic "contingency-shaped behaviors". Elements of behaviorism and cognitive psychology were synthesized to form the basis of cognitive behavioral therapy, a form of psychotherapy modified from techniques developed by American psychologist Albert Ellis and American psychiatrist Aaron T. Beck. Cognitive psychology was subsumed along with other disciplines, such as philosophy of mind, computer science, and neuroscience, under the umbrella discipline of cognitive science.
45.6.Schools of thought
Various schools of thought have argued for a particular model to be used as a guiding theory by which all, or the majority, of human behavior can be explained. The popularity of these has waxed and waned over time. Some psychologists may think of themselves as adherents to a particular school of thought and reject the others, although most consider each as an approach to understanding the mind, and not necessarily as mutually exclusive theories. On the basis of Tinbergen's four questions a framework of reference of all fields of psychological research can be established (including anthropological research and humanities).
In modern times, psychology has adopted an integrated perspective towards understanding consciousness, behavior, and social interaction. This perspective is commonly referred to as the biopsychosocial approach. The basic tenet of the biopsychosocial model is that any given behavior or mental process affects and is affected by dynamically interrelated biological, psychological, and social factors. The psychological aspect refers to the role that cognition and emotions play in any given psychological phenomenon for example, the effect of mood or beliefs and expectations on an individual's reactions to an event. The biological aspect refers to the role of biological factors in psychological phenomena—for example, the effect of the prenatal environment on brain development and cognitive abilities, or the influence of genes on individual dispositions. The socio-cultural aspect refers to the role that social and cultural environments play in a given psychological phenomenon for example, the role of parental or peer influence in the behaviors or characteristics of an individual.
Psychology encompasses a vast domain, and includes many different approaches to the study of mental processes and behavior. Below are the major areas of inquiry that comprise psychology. A comprehensive list of the sub-fields and areas within psychology can be found at the list of psychology topics and list of psychology disciplines.
Abnormal psychology is the study of abnormal behavior in order to describe, predict, explain, and change abnormal patterns of functioning. Abnormal psychology studies the nature of psychopathology and its causes, and this knowledge is applied in clinical psychology to treat patients with psychological disorders.
It can be difficult to draw the line between normal and abnormal behaviors. In general, abnormal behaviors must be maladaptive and cause an individual significant discomfort in order to be of clinical and research interest. According to the DSM-IV-TR, behaviors may be considered abnormal if they are associated with disability, personal distress, the violation of social norms, or dysfunction.
Biological psychology is the scientific study of the biological substrates of behavior and mental states. Seeing all behavior as intertwined with the nervous system, biological psychologists feel it is sensible to study how the brain functions in order to understand behavior. This is the approach taken in behavioral neuroscience, cognitive neuroscience, and neuropsychology. Neuropsychology is the branch of psychology that aims to understand how the structure and function of the brain relate to specific behavioral and psychological processes. Neuropsychology is particularly concerned with the understanding of brain injury in an attempt to work out normal psychological function. The approach of cognitive neuroscience to studying the link between brain and behavior is to use neuroimaging tools, such as to observe which areas of the brain are active during a particular task.
Clinical psychology includes the study and application of psychology for the purpose of understanding, preventing, and relieving psychologically-based distress or dysfunction and to promote subjective well-being and personal development. Central to its practice are psychological assessment and psychotherapy, although clinical psychologists may also engage in research, teaching, consultation, forensic testimony, and program development and administration. Some clinical psychologists may focus on the clinical management of patients with brain injury this area is known as clinical neuropsychology. In many countries clinical psychology is a regulated mental health profession.
The work performed by clinical psychologists tends to be influenced by various therapeutic approaches, all of which involve a formal relationship between professional and client (usually an individual, couple, family, or small group). The various therapeutic approaches and practices are associated with different theoretical perspectives and employ different procedures intended to form a therapeutic alliance, explore the nature of psychological problems, and encourage new ways of thinking, feeling, or behaving. The four major theoretical perspectives are Psychodynamic, Cognitive Behavioral, Existential-Humanistic, and Systems or Family therapy. There has been a growing movement to integrate the various therapeutic approaches, especially with an increased understanding of issues regarding culture, gender, spirituality, and sexual-orientation. With the advent of more robust research findings regarding psychotherapy, there is growing evidence that most of the major therapies are about of equal effectiveness, with the key common element being a strong therapeutic alliance. Because of this, more training programs and psychologists are now adopting an
eclectic therapeutic orientation.
Cognitive psychology studies cognition, the mental processes underlying mental activity. Perception, learning, problem solving, reasoning, thinking, memory, attention, language and emotion are areas of research. Classical cognitive psychology is associated with a school of thought known as cognitivism, whose adherents argue for an information processing model of mental function, informed by functionalism and experimental psychology.
On a broader level, cognitive science is an interdisciplinary enterprise of cognitive psychologists, cognitive neuroscientists, researchers in artificial intelligence, linguists, human–computer interaction, computational neuroscience, logicians and social scientists. Computational models are sometimes used to simulate phenomena of interest. Computational models provide a tool for studying the functional organization of the mind whereas neuroscience provides measures of brain activity.
Community psychology deals with the relationships of the individual to communities and the wider society. Community psychologists seek to understand the quality of life of individuals, communities, and society. Their aim is to enhance quality of life through collaborative research and action Community Psychology makes use of various perspectives within and outside of Psychology to address issues of communities, the relationships within them, and people's attitudes about them. Through collaborative research and action, community psychologists (practitioners and researchers) seek to understand and to enhance quality of life for individuals, communities, and society. Community psychology takes a public health approach and focuses on prevention and early intervention as a means to solve problems in addition to treatment. Rappaport (1977) discusses the perspective of community psychology as an ecological perspective with the person-environment fit being the focus of study and action instead of attempting to change the person or the environment when an individual is seen as having a problem
Comparative psychology refers to the study of the behavior and mental life of animals other than human beings. It is related to disciplines outside of psychology that study animal behavior such as ethology. Although the field of psychology is primarily concerned with humans the behavior and mental processes of animals is also an important part of psychological research. This being either as a subject in its own right (e.g., animal cognition and ethology) or with strong emphasis about evolutionary links, and somewhat more controversially, as a way of gaining an insight into human psychology. This is achieved by means of comparison or via animal models of emotional and behavior systems as seen in neuroscience of psychology (e.g., affective neuroscience and social neuroscience).
Counseling psychology seeks to facilitate personal and interpersonal functioning across the lifespan with a focus on emotional, social, vocational, educational, health-related, developmental, and organizational concerns. Counselors are primarily clinicians, using psychotherapy and other interventions in order to treat clients. Traditionally, counseling psychology has focused more on normal developmental issues and everyday stress rather than psychopathology, but this distinction has softened over time. Counseling psychologists are employed in a variety of settings, including universities, hospitals, schools, governmental organizations, businesses, private practice, and community mental health centers.
Critical psychology applies the methodology of critical theory to psychology. Accordingly, it seeks to identify the supportive roles that psychology and psychologists play, often unwittingly, in oppressive ideologies, and it strives to replace these roles with ones that can transform oppressive social structures. Critical psychology operates on the belief "that mainstream psychology has institutionalized a narrow view of the field’s ethical mandate to promote human welfare" and critical psychology endeavors to broaden the view of that mandate.
A critical psychologist might ask whether a case of "work stress" warrants efforts to change the macro-level systems that control the work,] rather than to treat in isolation those individuals who experience the stress. One might also ask why "mainstream trauma efforts fail to incorporate a focus on human rights and social justice" in war-ravaged communities. In short, critical psychology seeks, where it deems appropriate, to raise psychology's level of analysis from the individual to society, and to render psychology more foundationally transformative than superficially ameliorative. Critical psychology has been applied to a wide array of psychology's other subfields, and many of its theorists are employed in mainstream psychological professions.
Mainly focusing on the development of the human mind through the life span, developmental psychology seeks to understand how people come to perceive, understand, and act within the world and how these processes change as they age. This may focus on intellectual, cognitive, neural, social, or moral development. Researchers who study children use a number of unique research methods to make observations in natural settings or to engage them in experimental tasks. Such tasks often resemble specially designed games and activities that are both enjoyable for the child and scientifically useful, and researchers have even devised clever methods to study the mental processes of small infants. In addition to studying children, developmental psychologists also study aging and processes throughout the life span, especially at other times of rapid change (such as adolescence and old age). Developmental psychologists draw on the full range of theorists in scientific psychology to inform their research.
Educational psychology is the study of how humans learn in educational settings, the effectiveness of educational interventions, the psychology of teaching, and the social psychology of schools as organizations. The work of child psychologists such as Lev Vygotsky, Jean Piaget and Jerome Bruner has been influential in creating teaching methods and educational practices. Educational psychology is often included in teacher education programs, at least in North America, Australia, and New Zealand.
Evolutionary psychology explores the genetic roots of mental and behavioral patterns, and posits that common patterns may have emerged because they were highly adaptive for humans in the environments of their evolutionary past—even if some of these patterns are maladaptive in today's environments. Fields closely related to evolutionary psychology are animal behavioral ecology, human behavioral ecology, dual inheritance theory, and sociobiology. Memetics, founded by British evolutionary biologist Richard Dawkins, is a related but competing field that proposes that cultural evolution can occur in a Darwinian sense but independently of Mendelian mechanisms; it therefore examines the ways in which thoughts, or memes, may evolve independently of genes.
Forensic psychology applies psychology to legal cases, covering a broad range of practices including the clinical evaluations of defendants, reports to judges and attorneys, and courtroom testimony on given issues. Forensic psychologists are appointed by the court or hired by attorneys to conduct competency to stand trial evaluations, competency to be executed evaluations, sanity evaluations, involuntary commitment evaluations, provide sentencing recommendations, and sex offender evaluation and treatment evaluations and provide recommendations to the court through written reports and testimony. Many of the questions the court asks the forensic psychologist go ultimately to legal issues, although a psychologist cannot answer legal questions. For example, there is no definition of sanity in psychology. Rather, sanity is a legal definition that varies from place to place throughout the world. Therefore, a prime qualification of a forensic psychologist is an intimate understanding of the law, especially criminal law.
Global psychology is a subfield of psychology that addresses the issues raised in the global sustainability debate. Like critical psychology, global psychology expands the objective of psychology to macro-level trends; it examines the overwhelming consequences of global warming, economic destabilization and other large-scale phenomena, while recognizing that global sustainability can best be achieved by psychologically sound individuals and cultures. Global psychologists advocate a simple and sensible, yet comprehensive, psychology, whose strength is its focus on the long-term well-being of all of humanity.
Health psychology is the application of psychological theory and research to health, illness and health care. Whereas clinical psychology focuses on mental health and neurological illness, health psychology is concerned with the psychology of a much wider range of health-related behavior including healthy eating, the doctor-patient relationship, a patient's understanding of health information, and beliefs about illness. Health psychologists may be involved in public health campaigns, examining the impact of illness or health policy on quality of life and in research into the psychological impact of health and social care.
Industrial and organizational psychology (I/O) applies psychological concepts and methods to optimize human potential in the workplace. Personnel psychology, a subfield of I/O psychology, applies the methods and principles of psychology in selecting and evaluating workers. I/O psychology's other subfield, organizational psychology, examines the effects of work environments and management styles on worker motivation, job satisfaction, and productivity.
Legal psychology is a research-oriented field populated with researchers from several different areas within psychology (although social and cognitive psychologists are typical). Legal psychologists explore such topics as jury decision-making, eyewitness memory, scientific evidence, and legal policy. The term "legal psychology" has only recently come into use, and typically refers to any non-clinical law-related research.
Occupational health psychology (OHP) is a discipline that emerged out of health psychology, industrial/organizational psychology, and occupational health. OHP is concerned with identifying psychosocial characteristics of workplaces that give rise to problems in physical (e.g., cardiovascular disease) and mental health (e.g., depression). OHP has investigated such psychosocial characteristics of workplaces as workers' decision latitude and supervisors' supportiveness. OHP also concerns itself with interventions that can prevent or ameliorate work-related health problems. Such interventions have important, beneficial implications for the economic success of organizations. Other research areas of concern to OHP include workplace violence, unemployment, and workplace safety. Two exemplary OHP journals are the Journal of Occupational Health Psychology and Work & Stress. Two prominent OHP professional organizations include the European Academy of Occupational Health Psychology and the Society for Occupational Health Psychology.
Personality psychology studies enduring patterns of behavior, thought, and emotion in individuals, commonly referred to as personality. Theories of personality vary across different psychological schools and orientations. They carry different assumptions about such issues as the role of the unconscious and the importance of childhood experience. According to Freud, personality is based on the dynamic interactions of the ego, superego, and id. Trait theorists, in contrast, attempt to analyze personality in terms of a discrete number of key traits by the statistical method of factor analysis. The number of proposed traits has varied widely. An early model proposed by Hans Eysenck suggested that there are three traits that comprise human personality: extraversion-introversion, neuroticism, and psychoticism. Raymond Cattell proposed a theory of 16 personality factors. The "Big Five" or Five Factor Model, proposed by Lewis Goldberg currently has strong support among trait theorists.
46.0.Research Methods in Psychology
Research psychology encompasses the study of behavior for use in academic settings, and contains numerous areas. It contains the areas of abnormal psychology, biological psychology, cognitive psychology, comparative psychology, developmental psychology, personality psychology, social psychology and others. All branches of psychology can have a research component to them. Research psychology is contrasted with applied psychology.
Research in psychology is conducted in broad accord with the standards of the scientific method, encompassing both qualitative ethological and quantitative statistical modalities to generate and evaluate explanatory hypotheses with regard to psychological phenomena. Where research ethics and the state of development in a given research domain permits, investigation may be pursued by experimental protocols. Psychology tends to be eclectic, drawing on scientific knowledge from other fields to help explain and understand psychological phenomena. Qualitative psychological research utilizes a broad spectrum of observational methods, including action research, ethography, exploratory statistics, structured interviews, and participant observation, to enable the gathering of rich information unattainable by classical experimentation. Research in humanistic psychology is more typically pursued by ethnographic, historical, and historiographic methods.
The testing of different aspects of psychological function is a significant area of contemporary psychology. Psychometric and statistical methods predominate, including various well-known standardized tests as well as those created ad hoc as the situation or experiment requires.
Academic psychologists may focus purely on research and psychological theory, aiming to further psychological understanding in a particular area, while other psychologists may work in applied psychology to deploy such knowledge for immediate and practical benefit. However, these approaches are not mutually exclusive and most psychologists will be involved in both researching and applying psychology at some point during their career. Clinical psychology, among many of the various disciplines of psychology, aims at developing in practicing psychologists knowledge of and experience with research and experimental methods which they will continue to build up as well as employ as they treat individuals with psychological issues or use psychology to help others.
When an area of interest requires specific training and specialist knowledge, especially in applied areas, psychological associations normally establish a governing body to manage training requirements. Similarly, requirements may be laid down for university degrees in psychology, so that students acquire an adequate knowledge in a number of areas. Additionally, areas of practical psychology, where psychologists offer treatment to others, may require that psychologists be licensed by government regulatory bodies as well.
Quantitative psychology involves the application of statistical analysis to psychological research, and the development of novel statistical approaches for measuring and explaining human behavior. It is a young field (only recently have Ph.D. programs in quantitative psychology been formed), and it is loosely comprised of the subfields psychometrics and mathematical psychology.
Psychometrics is the field of psychology concerned with the theory and technique of psychological measurement, which includes the measurement of knowledge, abilities, attitudes, and personality traits. Measurement of these unobservable phenomena is difficult, and much of the research and accumulated knowledge in this discipline has been developed in an attempt to properly define and quantify such phenomena. Psychometric research typically involves two major research tasks, namely: (i) the construction of instruments and procedures for measurement; and (ii) the development and refinement of theoretical approaches to measurement.
Psychology is a science and therefore, must be approached as such. This means that the scientific method must be used, especially in designing an experiment.
There are several research methods that psychologists employ:
Although there are many different kinds of research designs in psychology, the general kinds of studies are: descriptive or qualitative, correlational, and experimental. The method of data collection also varies, with self-report on one end of the spectrum and naturalistic observation on the other.
Studies that do not test specific relationships between variables are called descriptive studies. In this research method, general or specific behaviors or attributes are observed and measured, without respect to each other. These studies are generally the design of choice for breaking into new areas, as the vast but often inconclusive amount of information collected can be drawn upon for future hypotheses.
An example of such a study would be a researcher inquiring into the quality of mental health institutions. This would be done by observation or measurements of various criteria, as opposed to relationships between variables. Alternatively, the study could be conducted without any specific criteria in mind.
This method of statistical analysis shows the relationship between two variables. For example, research has shown that alcohol dependence correlates with depression. That is to say, the more alcohol people consume, the more depressed they become. On the other hand, it could be the other way around as well: the more depressed people become, the more likely they are to consume alcohol.
The attributes of correlations include strength and direction. The direction may be positive (both variables both increase or decrease together), negative (one variable increases while the other decreases) or unrelated (a random relationship between variables). The strength of a correlation ranges from -1 to +1 with a 0 reflecting no relationship between variables. A correlational study serves only to describe/predict behavior and not to explain it. This is so because a third variable could be shown to cause the occurrence of one of the variables. Furthermore, only experiments can prove causation.
Experiments are generally the studies that are the most precise and have the most weight to them due to their conclusive power. They are particularly effective in proving hypotheses about cause and effect relationships between variables. A hypothesis is a prediction of how one variable relates to another. There are two types of hypotheses, null and directional. The null is a prediction that there will not be any change in the dependent variable when the researcher changes the independent variable. The directional hypothesis states that the change in the independent variable will induce a change in the dependent variable. In a true experiment, all variables are held constant except for the independent variable, which is manipulated. Thus, any changes in the experimental groups can be solely attributed to the action of the independent variable. This is called being objective.
For instance, in an experiment to test whether music improves people's memories, we would have a sheet of paper with ten unrelated words on it for people to memorize. The control group would have no music playing in the background while the experimental group would have some music in the background. Because as researchers we have adhered to the scientific method and held all variables as constant as possible, if the experimental group does report better recollection of words, then we could assume that the music had an effect on memory. However, we must be certain to do our best to ensure that any controllable differences between the two groups are eliminated in order to ensure that no confounding variable interferes with the experiment.
There are two main ways to pick, or sample the subjects in an experiment, random and stratified. In a random sampling each person has an equal chance at being picked. This means that if 90% of the population being sampled from are Christian then 90% of the sample will be Christian. If the researcher wanted all religions represented equally he would employ stratified sampling. For instance, the experiment could be performed only on women, or on mixed groups with equal numbers of each sex in them, to eliminate the possibility of biased results from one gender having better average memory than the other.
Steps must be taken to make sure that there is no experimenter bias. Two common forms of bias are demand characteristics and expectancy effects. If a researcher expects certain results from an experiment and influences the subjects response this is called demand characteristics. If the experimenter inadvertently interprets the information to be as expected in his hypothesis it is called expectancy effect. To counteract experimenter bias the subjects can be kept uninformed on the intentions of the experiment, which is called single blind. If the people collecting the information and the subjects giving it are kept uninformed then it is called a double blind experiment.
The experiment should also be reported so that other researchers can repeat it. If an experiment isn't repeatable it will not hold much weight in the scientific community. To help an experiment be repeatable the researcher should have the variables be measureable, this is called being empirical.
Whether researching humans or animals the experiment should be ethical. When humans are the subjects they should be informed of what the study is, consent to being in it, be debriefed afterwards, and their information should also be kept confidential.
Researchers study organisms in their natural environments or habitats without trying to manipulate or control anything. In this method, the researcher observes the behavior under study in its natural setting while attempting to avoid influencing or controlling it. The observations are done in a naturalistic setting without any preparation or participation of the researcher. Therefore, the behavior is observed in public places, streets, homes, and schools. Observing people from other cultures response in the same setting is a way to provide information for cross-cultural research.
This method includes tests, questionnaires, and interviews. All of which do the same thing, give the subject a stimuli, i.e. the question, and get a response. The advantage of using these is the ability to inexpensively and rapidly collect vast amounts of data. This allows a psychologist to compare one person, or a group of peoples results to thousands of others. The disadvantage is that they are not always telling what the subject's response is but what the subject says is the response.
Once the information is gathered it has to be put into some kind of form, usually numerical. Statistics deals with the collection, analysis, interpretation, and presentation of numerical data. The goal of statistics is to summarize the data and let descriptions or inferences be made. Inferences are used when making predictions of the relationships of variables. Descriptions are concise displays, using statistical symbols, of the information in frequency distributions, measures of central tendency, or measures of variability.
There are agreed upon standard symbols used in statistical displays. These symbols can be used by themselves or in equations.
N = number of scores
X = score (or scores)
M = mean
d = difference of a score from the mean
Σ = sum of
D = difference in rank
r or ρ = correlation
SD = standard deviation
A frequency distribution is obtained by taking the score and splitting them into subgroups. The subgroups are then put on either a histogram (bar graph) or a frequency polygram (line graph). When a frequency distribution has most of the scores on one side of the graph it is considered skewed. If it has most of the scores in the middle with equal amounts on both sides it is considered symmetrical.
46.6.4.Measures of Central Tendency
In measures of central tendency there is one number that is used to represent a group of numbers. This number is the mean, median, or the mode.
46.6.5.Measures of Variability
Variability is concerned with the dispersement of the scores, called variability i.e. are the scores clustered together or spread out. Range and standard deviation are the measures most commonly used. To find the range just subtract the number of the lowest score from the number of the highest score. This can be deceiving if most of the scores are bunched together and one of the scores is very far away from it. In this case standard deviation must be used. A formula commonly used for standard deviation is SD = the square root of Σd²/N.
In the course of treating a patient a psychologist will take records of problems, insights, and techniques that were important in the patients treatment. A clinical case history may be drawn upon by researchers to expose a factor that is important for understanding a behavior.
a. Independent variable = variable that one manipulates in order to see if it has any effect on the dependent variable (eg. in the example above, the independent variable would be music and its effect on memory)
b. dependent variable = variable that depends on the effect of the independent variable (eg. in the example above, the dependent variable would be memory and better recollection of words)
c. double-blind procedure = procedure in which neither the researcher nor the subjects know which group (experimental or control) the subjects are in in order to minimize experimenter cues.
d. single-blind procedure = procedure in which only the researcher knows which group which kind of subject is in.
e. experimenter cues - subtle and often unintentional cues that the experimenter makes which implies which group which kind of subject is in. for example, if an experimenter believes that music does indeed improve memory, some cues would be the experimenter's smiling/winking at the experimental group. This smile/wink would imply to the subjects in the experimental group that the researcher is secretly implying that they're in the experimental group.
f. placebo effect - a treatment works because of the patient's belief that it works and not because it actually does.
g. experimenter - the person who is researching through the participant.
47.1.Status as a science
Criticisms of psychology often come from perceptions that it is a "fuzzy" science. Philosopher Thomas Kuhn's 1962 critique implied psychology overall was in a pre-paradigm state, lacking the agreement on overarching theory found in mature sciences such as chemistry and physics. Psychologists and philosophers have addressed the issue in various ways. Because some areas of psychology rely on research methods such as surveys and questionnaires, critics have asserted that psychology is not scientific (due to the largely correlational nature of survey research). Other phenomena that psychologists are interested in such as personality, thinking, and emotion cannot be directly measured and are often inferred from subjective self-reports, which may be problematic.
Misuses of hypothesis-testing occur in psychology, particularly by psychologists without doctoral training in experimental psychology and statistics. Research has documented that many psychologists confuse statistical significance with practical importance. Statistically significant but practically unimportant results are common with large samples. Some psychologists have responded with an increased use of effect size statistics, rather than sole reliance on the Fisherian p < .05 significance criterion (whereby an observed difference is deemed 'statistically significant' if an effect of that size or larger would occur with 5% (or less) probability in independent replications, assuming the truth of the null-hypothesis of no difference between the treatments).
Sometimes the debate comes from within psychology, for example between laboratory-oriented researchers and practitioners such as clinicians. In recent years, and particularly in the U.S., there has been increasing debate about the nature of therapeutic effectiveness and about the relevance of empirically examining psychotherapeutic strategies. One argument states that some therapies are based on discredited theories and are unsupported by empirical evidence. The other side points to recent research suggesting that all mainstream therapies are of about equal effectiveness, while also arguing that controlled studies often do not take into consideration real-world conditions.
47.2. Fringe clinical practices
There is also concern about a perceived gap between scientific theory and its application, in particular with the application of unproven or unsound clinical practices. Researchers such as Beyerstein (2001) say there has been a large increase in the number of mental health training programs that do not emphasize science training. According to Lilienfeld (2002) "a wide variety of unvalidated and sometimes harmful psychotherapeutic methods, including facilitated communication for infantile autism... suggestive techniques for memory recovery (e.g., hypnotic age-regression, guided imagery, body work), energy therapies (e.g., Thought Field Therapy, Emotional Freedom Technique)... and New Age therapies of seemingly endless stripes (e.g., rebirthing, reparenting, past-life regression, primal therapy, neurolinguistic programming, alien abduction therapy, angel therapy) have either emerged or maintained their popularity in recent decades." Allen Neuringer made a similar point in the field of the experimental analysis of behavior in 1984.
Ashby, F. G.& Casale, M. B. (2005). FROST: A distributed neurocomputational model of working memory maintenance. Journal of Cognitive Neuroscience
Anderson, M (1995). Sexual Selection. Princeton, New Jersey: Princeton University Press.
Atkinson, R. C., & Shiffrin, R. M. (1968). Human memory: A proposed system and its control processes.The psychology of learning and motivation (Vol. 2, pp. 89-195). New York: Academic Press.
Baddeley, A. (2003). Working memory: Looking back and looking forward. Nature
Baddeley, A.D. Hitch, G.J.L (1974). Working Memory, In G.A. Bower (Ed.), the psychology of learning and motivation: advances in research and theory (Vol. 8, pp. 47-89), New York: Academic Press.
Barlow GW. (2005). How Do We Decide that a Species is Sex-Role Reversed? The Quarterly Review of Biology 80(1):28–35.
Bejerano G, Makunin I, Stephen S, (2004). Ultra conserved elements in the human genome. Science 304:1321-5
Bhowmick NA, Chytil A, Plieth D, et al. (2004). "TGF-beta signaling in fibroblasts modulates the oncogenic potential of adjacent epithelia".
Brown, G. D. A., Neath, I., & Chater, N. (2007). A ratio model of scale-invariant memory and identification. Psychological Review, 114, 539-576.
Berman, M. G., & Moore, K. S. (2008). The mind and brain of short-term memory. Annual Review of Psychology, 59, 193-224.
Baddeley, A. D., Thomson, N., & Buchanan, M. (1975). Word length and the structure of short term memory. Journal of Verbal Learning and Verbal Behavior, 14, pp. 575–589.
Barrouillet, P., Bernardin, S., & Camos, V. (2004). Time constraints and resource sharing in adults' working memory spans. Journal of Experimental Psychology:
Conway Zirkle (1941). Natural Selection before the "Origin of Species",
Conrad, R., & Hull, A. J. (1964). Information, acoustic confusion and memory span.
Cherry, E.C.(1958).Some experiments on the recognition of speech with one and two ears.
Cowan, N. (2001). The magical number 4 in short-term memory: A reconsideration of mental storage capacity. Behavioral and Brain Sciences, 24, 87-185
Cowan, N. (2001). The magical number 4 in short-term memory: A reconsideration of mental storage capacity. Behavioral and Brain Sciences, 24, pp. 1–185.
Cowan, N. (2001). The magical number 4 in short-term memory: A reconsideration of mental storage capacity. Behavioral and Brain Sciences, 24, 97-185.
Charles Darwin; ed. Nora Barlow (1958). "The autobiography of Charles Darwin 1809-1882". London: Collins. pp. 120.
Collier, Judith. et al. (2006). Oxford Handbook of Clinical Specialties 7th edn. Oxford. pp. 350–1.
Conway, A. R. A. & Engle, R. W. (2003). Working memory capacity and its relation to general intelligence. Trends in Cognitive Sciences, 7, 547-552.
Curtis, C. E., & D'Esposito, M. (2003). Persistent activity in the prefrontal cortex during working memory. Trends in Cognitive Sciences.
Collette, F& Van der Linden, M. (2006). Exploration of the neural subtrates of executive functioning by functional neuroimaging. Neuroscience.
Davelaar, E. J. & Usher, M. (2005): The demise of short-term memory revisited: empirical and computational investigation of decency effects. Psychological Review, 112, pp. 3–42.
Daneman, M., & Carpenter, P. A. (1980). Individual differences in working memory and reading. Journal of Verbal Learning and Verbal Behavior, 19(4), 450-466.
Dawkins R. (1989). The Selfish Gene. Oxford University Press: New York, NY, USA, p.192.
Dennett DC. (1991). Consciousness Explained. Little, Brown, and Co: New York, NY, USA.
Dobzhansky (1937). Genetics and the Origin of Species. Columbia University Press, New York.
D.E. Moody (2009). "Can intelligence be increased by training on a task of working memory?"Intelligence 37 (4): 327-328.
Endo K, Matsumoto T, Kobayashi T, (2005). "Diabetes-related changes in contractile responses of stomach fundus to endothelin-1 in streptozotocin-induced diabetic rats.
Eons M, Pinxten R. (2000). Sex-role reversal in vertebrates: behavioral and endocrinological accounts.
Ender JA (1986). Natural Selection in the Wild. Princeton, New Jersey: Princeton University Press.Easley L. (1958). Darwin's Century: Evolution and the Men Who Discovered It. Doubleday & Co: New York, USA.
Engle, R. W,& Conway, A. R. A. (1999). Working memory, short term memory and general fluid intelligence: A latent variable approach. Journal of Experimental Psychology:
Fisher RA (1930). The Genetical Theory of Natural Selection. Clarendon Press, Oxford.
Futuyma DJ (2005). Evolution. Sinauer Associates, Inc., Sunderland, Massachusetts. Falconer DS & Mackay TFC (1996). Introduction to Quantitative Genetics. Addison Wesley Longman, Harlow, Essex,
Frühbeck G (July 2004). "The adipose tissue as a source of vasoactive factors".
Fuster, J. M. (1997). The Prefrontal Cortex: Anatomy, physiology, and neuropsychology of the frontal lobe : Lippincott.
Fuster, J. M. (1973). Unit-activity in prefrontal cortex during delayed-response performance - neuronal correlates of transient memory. Journal of Neurophysiology, 36, 61-78.
Gales F (1999).Why do almost all mammals have seven cervical vertebrae? Developmental constraints,
Goldberg DE. (1989). Genetic Algorithms in Search, Optimization and Machine Learning. Addison-Wesley: Boston, MA, USA
Gould, Stephen Jay (2002). The Structure of Evolutionary Theory. Harvard University Press.
Gobet, F. (2000). Some shortcomings of long-term working memory. British Journal of Psychology, 91, 551-570.
Guida, A., & Tardieu, H. (2005). Is personalization a way to operationalise long-term working memory?Current Psychology Letters: Behaviour, Brain & Cognition, 15(1), 1-15.
Hulme, C., Roodenrys, G.& Mercer, R. (1995). The role of long-term memory mechanisms in memory span. British Journal of Psychology, 86, 527-536.
Haldane, J.B.S. 1953. The measurement of natural selection. Proceedings of the 9th International Congress of Genetics
Haldane JBS (1932). The Causes of Evolution. The cost of natural selection.
Hamilton WD. (1964). The genetical evolution of social behavior I and II. Journal of Theoretical Biology.
He L, Hannon GJ. (2004). MicroRNAs: small RNAs with a big role in gene regulation. Nat Rev Genet 5(7)
Halford, G. S., Baker, R., McCredden, J. E., & Bain, J. D. (2005). How many variables can humans process? Psychological Science, 16, 70-76.
Honey, G. D, Brammer, M. J. (2002). Effects of verbal working memory load on corticocortical connectivity modeled by path analysis of functional magnetic resonance imaging data. NeuroImage.
Julian Huxley (2003). The Origin of Species. Signet Classics. On the origin of species by means of natural selection, or the preservation of favored races in the struggle for life.
Just, M. A. & Carpenter, P. A. (1992). A capacity theory of comprehension: Individual differences in working memory. Psychological Review, 99, 122-149
Jaeggi, S. M., & Perrig, W. J. (2008). Improving fluid intelligence with training on working memory.
Kryukov GV, Schmidt S & Sunyaev S (2005). Small fitness effect of mutations in highly conserved non-coding regions. Human Molecular Genetics 14:2221-9
Kuhn TS (1996). The Structure of Scientific Revolution 3rd ed. University of Chicago Press:
Kauffman SA (1993) The Origin of order. Self-organization and selection in evolution.
Kasper et al. (2005). Harrison's Principles of Internal Medicine. McGraw Hill. pp. 2074.
Kraft U (2007). "Rhythm and Blues". Scientific American Mind.
Kaushansky K ( 2006). "Lineage-specific hematopoietic growth factors".
Kintsch, W., Patel, V., & Ericsson, A. (1999). The role of long-term working memory in text comprehension. Psychologia, 42, 186–198.
Klingberg, T., Forssberg, H., & Westerberg, H. (2002). Training of working memory in children with ADHD. Journal of Clinical & Experimental Neuropsychology, 24, 781-791.
Kane, M. J., & Engle, R. W. (2002). The role of prefrontal cortex in working-memory capacity, executive attention, and general fluid intelligence: An individual-differences perspective.
Kondo, H., Osaka, N. & Osaka, M. (2004). Cooperation of the anterior cinculate cortex and dorsolateral prefrontal cortex for attention shifting. NeuroImage, 23, 670-679.
Klimesch, W. (2006). Binding principles in the theta frequency range.
Lander R & Arnold SJ (1983). The measurement of selection on correlated characters. Lucy A, Guo H, Li W, Ding S (2000). "Suppression of post-transcriptional gene silencing by a plant viral protein localized in the nucleus."
Luck, S. J., & Vogel, E. K. (1997). The capacity of visual working memory for features and conjunctions. Nature, 390, 279-281
Lewandowsky, S & Brown, G. D. A. (2004). Time does not cause forgetting in short-term serial recall. Psychonomic Bulletin & Review, 11, 771-790.
Lehrl, S., & Fischer, B. (1988): The basic parameters of human information processing: their role in the determination of intelligence. Personality and individual Differences, 9, pp. 883–896.)
Lewandowsky, & Brown, G. D. A. (2004). Time does not cause forgetting in short-term serial recall. Psychonomic Bulletin & Review, 11, 771-790
Lange, E. B., & Oberauer, K. (2005).Overwriting of phonemic features in serial recall. Memory,
Mills SK, Beatty JH.(1994). The Propensity Interpretation of Fitness.
Mitchell, Melanie, (1996), An Introduction to Genetic Algorithms, MIT Press, Cambridge, MA.
Mayr E (1942). Systematics and the Origin of Species Columbia University Press, New York.
Maynard Smith, John (1993). The Theory of Evolution:
Miller, GA., Galanter, E. & Pribram, KH. (1960) "Plans and the Structure of Behavior."
M. J., & Engle, R. W. (2002). The role of prefrontal cortex in working-memory capacity, executive attention, and general fluid intelligence: An individual differences perspective
Miller, G. A. (1956). The magical number seven, plus or minus two: Some limits on our capacity for processing information. Psychological Review, 63, 81-97.
Maehara, Y., & Saito, S. (2007). The relationship between processing and storage in working memory span: Not two sides of the same coin. Journal of Memory and Language.
Mottaghy, F. M. (2006). Interfering with working memory in humans. Neuroscience..
Nairne, J. S., & Dutta, A. (1992). Spatial and temporal uncertainty in long-term memory. Journal of Memory and Language, 31, 396-407.
Nairne, J. S. (2002). Remembering over the short-term: The case against the standard model.
Orrell, David (2007). Apollo's Arrow Toronto: HarperCollins Publishers Ltd.
Oberauer, K., & Kliegl, R. (2006). A formal model of capacity limits in working memory.
Oberauer, K. (2002). Access to information in working memory: Exploring the focus of attention. Journal of Experimental Psychology: Learning, Memory, and Cognition, 28, 411-421.
Oberauer, K. R.& Wittmann, W. W. (2000). Working memory capacity - facets of a cognitive ability construct. Personality and individual Differences, 29, 1017-1045.
Oberauer, K. & Kliegl, R. (2006). A formal model of capacity limits in working memory.
Oberauer, K., & Lewandowsky, S. (2008). Forgetting in immediate serial recall: Decay, temporal distinctiveness, or interference? Psychological Review, 115, 544-576
.Olesen, P. J., Westerberg, H. & Klingberg, T. (2004). Increased prefrontal and parietal activity after training of working memory. Nature Neuroscience.
Owen, A. M. (1997). The functional organization of working memory processes within human lateral frontal cortex: The contribution of functional neuroimaging. European Journal of Neuroscience.
Osaka, N. Osaka, & Shibasaki, H. (2003). The neural basis of executive function in working memory: an fMRI study based on individual differences. NeuroImage, 21, 623-631.
O'Reilly, R., Busby, R. S., & Soto, R. (2003). Three forms of binding and their neural substrates: Alternatives to temporal synchrony. In A. Cleeremans (Ed.), The unity of consciousness:
Pitnick S & Markow TA (1994). Large-male advantage associated with the costs of sperm production in Drosophila hydei, a species with giant sperm.
Pitnick S (1996) Investment in testes and the cost of making long sperm in Drosophila.
Pinker S. (1995). The Language Instinct: How the Mind Creates Language. HarperCollins: New York, NY, USA
Popper, Karl (1978). Natural selection and the emergence of mind
Pentikäinen V, Erkkilä K, Suomalainen L, (2000). "Estradiol acts as a germ cell survival factor in the human testis in vitro".
Parmentier, F. G., & Mayberry, M. (2005). Transitional information in spatial serial memory: path characteristics affect recall performance. Journal of Experimental Psychology: Learning,
Poirier, M., & Saint-Aubin, J. (1996). Immediate serial recall, word frequency, item identity and item position. Canadian Journal of Experimental Psychology, 50, pp. 408–412.
Poirier, M., & Saint-Aubin, J. (1995). Memory for related and unrelated words: Further evidence on the influence of semantic factors in immediate serial recall. Quarterly Journal of Experimental Psychology, 48A, pp. 384–404.
Postle, B. R. (2006). Working memory as an emergent property of the mind and brain. Neuroscience,
Qin S, Hermans EJ, Fernández G. (2009). Acute psychological stress reduces working memory-related activity in the dorsolateral prefrontal cortex. Biol Psychiatry.
Rose H, Rose SPR, Jencks C. (2000). Alas, Poor Darwin: Arguments Against Evolutionary Psychology.
Rice SH. (2004). Evolutionary Theory: Mathematical and Conceptual Foundations. Sinauer Associates: Sunderland, Massachusetts, USA.
R.J. Sternberg (2008). "Increasing fluid intelligence is possible after all (Commentary).”
Raffone, A., & Wolters, G. (2001). A cortical mechanism for binding in visual working memory.
Sober E (1984; 1993) The Nature of Selection: Evolutionary Theory in Philosophical Focus.
Schito GC (2006). "The importance of the development of antibiotic resistance in Staphylococcus aureus". Clin Microbiol Infect 12 Suppl 1: 3–8
Sanyal S, Jansen HG, de Grip WJ, (1990). The eye of the blind mole rat, Spalax ehrenbergi.
Salzburger W, Baric S, Sturmbauer C. (2002). Speciation via introgressive hybridization in East African cichlids?
Sober, Elliott (1984) The Nature of Selection: Evolutionary Theory in Philosophical Focus.
Schacter, D. L. (1997): Searching for Memory: The Brain, the Mind, and the Past.
Tarnow, Eugen (2005): The Short Term Memory Structure In State-Of-The Art Recall/Recognition Experiments of Rubin, Hinton and Wentzel.
Tarnow, Eugen (2008): Short Term Memory May Be the Depletion of the Readily Releasable Pool of Presynaptic Neurotransmitter Vesicles.
Towse, J. N., Hitch, G. J., & Hutton, U. (2000). On the interpretation of working memory span in adults. Memory & Cognition, 28, 341-348
T. Klingberg (2009). The overflowing brain: information overload and the limits of working memory.
Waugh, N. C., & Norman, D. A. (1965). Primary memory. Psychological Review,
Williams GC (1966). Adaptation and Natural Selection. Oxford University Press.
Wilson, DS (2002). Darwin's Cathedral: Evolution, Religion, and the Nature of Society.
Williams, George C. (1966) Adaptation and Natural Selection: A Critique of Some Current Evolutionary Thought.
Williams George C. (1992) Natural Selection: Domains, Levels and Challenges.