Theories of Personality and Stage Theories. Modern

Perspectives of Psychology

Personality developmentPersonality development• Developmental psychology Developmental psychology studies the physical, studies the physical,

social,social, and psychological changes that occur at and psychological changes that occur at different ages anddifferent ages and stages over the lifespan, from stages over the lifespan, from conception to old age.conception to old age. The development of the The development of the beliefs, moods, and behaviorsbeliefs, moods, and behaviors that differentiate that differentiate among people.among people. The concept of The concept of personality personality refers to refers to the profile ofthe profile of stable beliefs, moods, and behaviors stable beliefs, moods, and behaviors that differentiatethat differentiate among children (and adults) who among children (and adults) who live in a particular society.live in a particular society.

• The profiles that differentiate children across culturesThe profiles that differentiate children across cultures of different historical times will not be the same of different historical times will not be the same becausebecause the most adaptive profiles vary with the the most adaptive profiles vary with the values ofvalues of the society and the historical era. An essay the society and the historical era. An essay on personalityon personality development written 300 years ago by development written 300 years ago by a New Englanda New England Puritan would have listed piety as a Puritan would have listed piety as a major psychologicalmajor psychological trait but that would not be trait but that would not be regarded as an important personalityregarded as an important personality trait in trait in contemporary America.contemporary America.

UUnderstandingnderstanding of personality of personality developmentdevelopment• Contemporary theorists emphasize personalityContemporary theorists emphasize personality

traits traits having to do with individualism, internalized having to do with individualism, internalized conscienceconscience,, sociability with strangers, the sociability with strangers, the ability ability to controlto control strong strong emotion emotion and impulse, and and impulse, and personal achievement.personal achievement.

• An important reason for the immaturity of our An important reason for the immaturity of our understandingunderstanding of personality development is the of personality development is the heavy relianceheavy reliance on questionnaires that are filled out on questionnaires that are filled out by parents ofby parents of children or the responses of older children or the responses of older children to questionnaires.children to questionnaires. Because there is less Because there is less use of behavioral observationsuse of behavioral observations of children, our of children, our theories of personality developmenttheories of personality development are not strong.are not strong.

HHypotheses regarding theypotheses regarding the early origins of early origins of personalitypersonality: a : a temperamental biastemperamental bias

• There are five different hypotheses regarding theThere are five different hypotheses regarding the early origins of personality.early origins of personality. One assumes that the One assumes that the child’s inherited biology, usuallychild’s inherited biology, usually called a called a temperamental bias, is an important basis for thetemperamental bias, is an important basis for the child’s later personality. Alexander Thomas and Stellachild’s later personality. Alexander Thomas and Stella ChessChess suggested there were nine temperamental suggested there were nine temperamental dimensionsdimensions along with three synthetic types they along with three synthetic types they called thecalled the difficult child, the easy child, and the child difficult child, the easy child, and the child who is slowwho is slow to warm up to unfamiliarity. to warm up to unfamiliarity.

• Longitudinal studies of childrenLongitudinal studies of children suggest that a shy suggest that a shy and fearful style of reacting toand fearful style of reacting to challenge and novelty challenge and novelty predicts, to a modest degree, anpredicts, to a modest degree, an adult personality adult personality that is passive to challenge and introvertedthat is passive to challenge and introverted in mood.in mood.

Importance of Importance of family family experienceexperience

Importance of Importance of family family experienceexperience• A second hypothesis regarding personality A second hypothesis regarding personality

developmentdevelopment comes from Sigmund Freud’s comes from Sigmund Freud’s suggestion that variationsuggestion that variation in the sexual and in the sexual and aggressive aims of the aggressive aims of the idid, which, which is biological is biological in nature, combined with in nature, combined with family family experience,experience, leads to the development of the leads to the development of the ego ego and and superegosuperego..

• Freud suggested that differences in parental Freud suggested that differences in parental socializationsocialization produced variation in anxiety produced variation in anxiety which, in turn, leadswhich, in turn, leads to different personalities.to different personalities.

Role of the Role of the socialsocial experiencesexperiences• A third set of hypotheses emphasizes direct socialA third set of hypotheses emphasizes direct social

experiences with parents. After World War II, experiences with parents. After World War II, AmericansAmericans and Europeans held the more benevolent and Europeans held the more benevolent idealistic conceptionidealistic conception of the child that described of the child that described growth as motivatedgrowth as motivated by affectionate ties to others by affectionate ties to others rather than by the narcissismrather than by the narcissism and hostilityand hostility implied by implied by Freud’s writings. Freud’s writings.

• JohnJohn Bowlby Bowlby contributed to this new emphasis on contributed to this new emphasis on the infant’sthe infant’s relationships with parents in his books on relationships with parents in his books on attachmentattachment.. Bowlby argued that the nature of the Bowlby argued that the nature of the infant’s relationshipinfant’s relationship to the caretakers and especially to the caretakers and especially the mother created a profilethe mother created a profile of emotional reactions of emotional reactions toward adults that might lasttoward adults that might last indefinitely.indefinitely.

CConcept of self critical to the child’soncept of self critical to the child’s personalitypersonality• OObjective experiencesbjective experiences develop different develop different

personality profiles becausepersonality profiles because they construct they construct different conceptions about themselvesdifferent conceptions about themselves and and others from the same experiences. The others from the same experiences. The notion thatnotion that each child imposes a personal each child imposes a personal interpretation to their experiencesinterpretation to their experiences makes the makes the concept of self critical to the child’sconcept of self critical to the child’s personality.personality.

• An advantage of awarding importance to a An advantage of awarding importance to a conceptconcept of self and personality development of self and personality development is that the process ofis that the process of identification with identification with parents and others gains in significance.parents and others gains in significance. All All children wish to possess the qualities that children wish to possess the qualities that theirtheir culture regards as good. Some of these culture regards as good. Some of these qualities are thequalities are the product of identification product of identification with each parent.with each parent.

OObservationsbservations of a child’s of a child’s behaviorbehavior• A final source of hypotheses regarding the origins ofA final source of hypotheses regarding the origins of

personality comes from inferences based on direct personality comes from inferences based on direct observationsobservations of a child’s behavior. This strategy, of a child’s behavior. This strategy, which relieswhich relies on induction, focuses on different on induction, focuses on different characteristics at differentcharacteristics at different ages. Infants differ in ages. Infants differ in irritability, three-year-oldsirritability, three-year-olds differ in shyness, and six-differ in shyness, and six-year-olds differ in seriousnessyear-olds differ in seriousness of mood. of mood.

• A major problem with this approach is thatA major problem with this approach is that each class each class of behavior can have different historical antecedents.of behavior can have different historical antecedents. Children who prefer to play alone rather thanChildren who prefer to play alone rather than with with others do so for a variety of reasons. Some might beothers do so for a variety of reasons. Some might be temperamentally shy and are uneasy with other temperamentally shy and are uneasy with other childrenchildren while others might prefer solitary activity.while others might prefer solitary activity.

The current categories of child The current categories of child psychopathologypsychopathology• The current categories of child psychopathologyThe current categories of child psychopathology influenced influenced

the behaviors that are chosen by scientiststhe behaviors that are chosen by scientists for study. for study. Fearfulness and Fearfulness and conduct disorder conduct disorder predominatepredominate in clinical in clinical referrals to psychiatrists and psychologists.referrals to psychiatrists and psychologists.

• A cluster of behaviors that includes avoidance ofA cluster of behaviors that includes avoidance of unfamiliar unfamiliar events and places, events and places, fear fear of dangerous animals,of dangerous animals, shyness with shyness with strangers, sensitivity to strangers, sensitivity to punishmentpunishment,, and extreme and extreme guilt guilt is is called the internalizing profile.called the internalizing profile.

• The cluster that includes disobedience toward parentThe cluster that includes disobedience toward parent and and teachers, teachers, aggression aggression to peers, excessive dominanceto peers, excessive dominance of of other children, and impulsive decisions isother children, and impulsive decisions is called the called the externalizing profile. These children are mostexternalizing profile. These children are most likely to be at likely to be at risk for later risk for later juvenile delinquencyjuvenile delinquency. The. The association association between inability of a three-year-old to inhibitbetween inability of a three-year-old to inhibit socially socially inappropriate behavior and later inappropriate behavior and later antisocialantisocial behavior behavior is the is the most reliable predictive relationmost reliable predictive relation between a characteristic between a characteristic scene in the young child andscene in the young child and later personality trait.later personality trait.

Influences on personality Influences on personality developmentdevelopment

• The influence comes from a variety of The influence comes from a variety of temperamenttemperament but especially ease of arousal, irritability, fearfulness,but especially ease of arousal, irritability, fearfulness, sociability, and activity level. sociability, and activity level.

• The experiential contributionsThe experiential contributions to personality include to personality include early attachment relations,early attachment relations, parental socialization, parental socialization, identification with parents,identification with parents, class, and ethnic groups, class, and ethnic groups, experiences with other children,experiences with other children, ordinal position in the ordinal position in the family, physical attractiveness,family, physical attractiveness, and school success or and school success or failure, along with a number of unpredictablefailure, along with a number of unpredictable experiences like experiences like divorcedivorce, early parental, early parental death, death, mental mental illness illness in the family, and supporting relationshipsin the family, and supporting relationships with with relatives or teachers.relatives or teachers.

The most important personality The most important personality profilesprofiles The most important personality profiles in a The most important personality profiles in a

particularparticular culture stem from the challenges to culture stem from the challenges to which the childrenwhich the children of that culture must of that culture must accommodate. Most childrenaccommodate. Most children must deal with three must deal with three classes of external challenges: classes of external challenges:

• unfamiliarity, especially unfamiliar people, tasks, unfamiliarity, especially unfamiliar people, tasks, andand situations; situations;

• request by legitimate authority or request by legitimate authority or conformityconformity to to and acceptance of their standards, and and acceptance of their standards, and

• dominationdomination by or attack by other children. by or attack by other children. In addition, allIn addition, all children must learn to control two children must learn to control two

important families ofimportant families of emotions: anxiety, fear, and emotions: anxiety, fear, and guilt, on the one hand, andguilt, on the one hand, and on the other, on the other, angeranger, , jealousyjealousy, and resentment., and resentment.

FFour important influences on our important influences on personalitypersonality• Of the four important influences on personality—Of the four important influences on personality—

identification, ordinal position, social class, and identification, ordinal position, social class, and parentalparental socialization—identification is the most socialization—identification is the most important. Byimportant. By six years of age, children assume that six years of age, children assume that some of the characteristicssome of the characteristics of their parents belong to of their parents belong to them and they experiencethem and they experience vicariously the emotion vicariously the emotion that is appropriate to thethat is appropriate to the parent’s experience. parent’s experience.

• A six-year-old girl identified withA six-year-old girl identified with her mother will her mother will experience pride should mother win aexperience pride should mother win a prize or be prize or be praised by a friend. However, she will experiencepraised by a friend. However, she will experience shame or anxiety if her mother is criticized or is shame or anxiety if her mother is criticized or is rejectedrejected by friends. The process of identification has by friends. The process of identification has greatgreat relevance to personalty development.relevance to personalty development.

Personality inventoryPersonality inventory

• Personality inventoryPersonality inventory is a is a method of personality method of personality assessment based on aassessment based on a questionnaire asking a person questionnaire asking a person to report feelings orto report feelings or reactions in certain situations.reactions in certain situations. Personality inventories, also called objective tests,Personality inventories, also called objective tests, are are standardized and can be administered to a number ofstandardized and can be administered to a number of people at the same time. people at the same time.

• A psychologist need not be presentA psychologist need not be present when the test is when the test is given, and the answers can usuallygiven, and the answers can usually be scored by a be scored by a computer. Scores are obtained by comparisoncomputer. Scores are obtained by comparison with with norms for each category on the test. A personalitynorms for each category on the test. A personality inventory may measure one factor, such as anxietyinventory may measure one factor, such as anxiety level, or it may measure a number of different level, or it may measure a number of different personalitypersonality traits at the same time, such as the traits at the same time, such as the Sixteen PersonalitySixteen Personality Factor Questionnaire (16 PF).Factor Questionnaire (16 PF).

Minnesota MultiphasicMinnesota Multiphasic Personality InventoryPersonality Inventory• The personality inventory used most often for diagnosingThe personality inventory used most often for diagnosing

psychological disorders is the psychological disorders is the Minnesota MultiphasicMinnesota Multiphasic Personality InventoryPersonality Inventory, generally referred to as, generally referred to as the MMPI. It the MMPI. It consists of 550 statements that the test takerconsists of 550 statements that the test taker has to mark as has to mark as “true,” “false,” or “cannot say.” “true,” “false,” or “cannot say.”

• AnswersAnswers are scored according to how they correspond with are scored according to how they correspond with thosethose given by persons with various psychological disorders,given by persons with various psychological disorders, including including depression, hysteria, paranoia, psychopathicdepression, hysteria, paranoia, psychopathic deviancydeviancy, and , and schizophreniaschizophrenia. The MMPI was originally. The MMPI was originally developed (and is still used) for the diagnosis of these anddeveloped (and is still used) for the diagnosis of these and other other serious psychological problems. However enoughserious psychological problems. However enough responses responses have been collected from people with less severehave been collected from people with less severe problems to problems to allow for reliable scoring of responsesallow for reliable scoring of responses from these persons as from these persons as well. well.

• Many people with no severeMany people with no severe disorder are now given the MMPI as disorder are now given the MMPI as an assessment toolan assessment tool when they begin when they begin psychotherapypsychotherapy, with , with scoring geared towardscoring geared toward personality attributes rather than clinical personality attributes rather than clinical disorders.disorders.

The California Psychological The California Psychological InventoryInventory• The California Psychological Inventory (CPI), basedThe California Psychological Inventory (CPI), based on less on less

extreme measures of personality than the MMPI,extreme measures of personality than the MMPI, assesses assesses traits, including dominance, responsibility, selfacceptance,traits, including dominance, responsibility, selfacceptance, and and socializationsocialization. In addition, some parts of. In addition, some parts of the test specifically the test specifically measure traits relevant to academicmeasure traits relevant to academic achievement. Another achievement. Another inventory designed to measure ainventory designed to measure a spectrum of personality spectrum of personality variables in variables in normal normal populationspopulations is the Personality Research is the Personality Research Form (PRF), whose Form (PRF), whose measurementmeasurement scales include scales include affiliationaffiliation, , autonomy, change,autonomy, change, endurance, and exhibition. endurance, and exhibition.

• The Neuroticism The Neuroticism ExtroversionExtroversion Openness Personality Openness Personality InventoryInventory and and Revised (NEO-PIR)Revised (NEO-PIR) also measures common also measures common dimensions of personalitydimensions of personality such as sensitivity and extroversion, such as sensitivity and extroversion, but it differs frombut it differs from other tests in its inclusion of both “private” other tests in its inclusion of both “private” and “public” versions. The questions in the private version are and “public” versions. The questions in the private version are answeredanswered like those in other personality inventories, but thelike those in other personality inventories, but the public version consists of having another person acquaintedpublic version consists of having another person acquainted with the test taker answer questions about himwith the test taker answer questions about him or her. or her. Significant discrepancies between the two versionsSignificant discrepancies between the two versions can be an can be an important source of information for thoseimportant source of information for those interpreting the test.interpreting the test.

Rorschach techniqueRorschach technique

• A projective personality assessment based on theA projective personality assessment based on the subject’s subject’s reactions to a series of ten inkblot pictures.reactions to a series of ten inkblot pictures. Popularly known Popularly known as the “Inkblot” test, the Rorschachas the “Inkblot” test, the Rorschach technique, or Rorschach technique, or Rorschach Psychodiagnostic Test isPsychodiagnostic Test is the most widely used projective the most widely used projective psychological test. Thepsychological test. The Rorschach is used to help assess Rorschach is used to help assess personality personality structurestructure and identify emotional problems. Like and identify emotional problems. Like other other projectiveprojective techniquestechniques, it is based on the principle , it is based on the principle that subjectsthat subjects viewing neutral, ambiguous stimuli will project viewing neutral, ambiguous stimuli will project theirtheir own personalities onto them, thereby revealing a varietyown personalities onto them, thereby revealing a variety of of unconscious unconscious conflicts and motivations. conflicts and motivations.

• AdministeredAdministered to both adolescents and adults, the Rorschach to both adolescents and adults, the Rorschach can also becan also be used with children as young as three years old. used with children as young as three years old. The testThe test provides information about a person’s thought provides information about a person’s thought processes,processes, perceptions, motivations, and attitude toward his perceptions, motivations, and attitude toward his or heror her environmentenvironment, and it can detect internal and external, and it can detect internal and external pressures and conflicts as well as illogical or psychoticpressures and conflicts as well as illogical or psychotic thought patterns.thought patterns.

Thematic Apperception Thematic Apperception TestTest• The Thematic Apperception Test is an untimed, The Thematic Apperception Test is an untimed,

individuallyindividually administered psychological test used for administered psychological test used for personalitypersonality assessment. Suitable for ages 14-40, it is assessment. Suitable for ages 14-40, it is used toused to identify dominant drives, emotions, and identify dominant drives, emotions, and conflicts, asconflicts, as well as levels of emotional maturity, well as levels of emotional maturity, observational skills,observational skills, imaginationimagination, and , and creativitycreativity. The . The subject is shown a seriessubject is shown a series of pictures, one at a time, and of pictures, one at a time, and asked to make up aasked to make up a story about each one, and his or story about each one, and his or her responses are evaluatedher responses are evaluated by a trained psychologist. by a trained psychologist.

• The test is usually givenThe test is usually given in two sessions, with 10 in two sessions, with 10 pictures shown in each one. Sessionspictures shown in each one. Sessions are untimed but are untimed but generally last about an hour. Forgenerally last about an hour. For children ages 3-10, children ages 3-10, see Children’s Apperception Test.see Children’s Apperception Test.

Major Perspectives in Major Perspectives in PsychologyPsychology

• Any given topic in contemporary psychology Any given topic in contemporary psychology can be approached from a variety ofcan be approached from a variety of perspectives. Each perspective discussed here perspectives. Each perspective discussed here represents a different emphasis orrepresents a different emphasis or point of point of view that can be taken in studying a particular view that can be taken in studying a particular behavior, topic, or issue.behavior, topic, or issue.

• TThe influence of the early schools of he influence of the early schools of psychology is apparentpsychology is apparent in the first four in the first four perspectives that characterize contemporary perspectives that characterize contemporary psychologypsychology..

The Biological The Biological PerspectivePerspective• The The biological perspective biological perspective emphasizesemphasizes studying the studying the

physical bases of human and animal behavior, includingphysical bases of human and animal behavior, including the the nervous system, endocrine system, immune system, and nervous system, endocrine system, immune system, and genetics.genetics. Interest in the biological perspective has grown in Interest in the biological perspective has grown in the last few decades,the last few decades, partly because of advances in partly because of advances in technology and medicine. For example, in the latetechnology and medicine. For example, in the late 1950s 1950s and early 1960s, medications were developed that helped and early 1960s, medications were developed that helped control the symptomscontrol the symptoms of serious psychological disorders, of serious psychological disorders, such as schizophrenia and depression.such as schizophrenia and depression.

• The relative success of these new drugs sparked new The relative success of these new drugs sparked new questionsquestions about the interaction among biological factors about the interaction among biological factors and human behavior,and human behavior, emotions, and thought processes.emotions, and thought processes. Equally important were technological advances that have Equally important were technological advances that have allowedallowed psychologists and other researchers to explore the psychologists and other researchers to explore the humanhuman brain as never before. The development of the PET brain as never before. The development of the PET scan, MRI scan,scan, MRI scan, and functional MRI (fMRI) scan has allowed and functional MRI (fMRI) scan has allowed scientists to study thescientists to study the structure and activity of the intact structure and activity of the intact brain. These and other advancesbrain. These and other advances have produced new have produced new insights into the biological bases of memory,insights into the biological bases of memory, learning, learning, mental disorders, and other behaviors. mental disorders, and other behaviors.

Looking at Brain-Scan Looking at Brain-Scan ImagesImages

Demonstration of Cortical Activities During Demonstration of Cortical Activities During SpeechSpeechThe figures show the pathway for reading and The figures show the pathway for reading and naming something that is seen, such as reading naming something that is seen, such as reading aloud. PET scans show the areas of the brain that are aloud. PET scans show the areas of the brain that are most activemost activeduring various phases of speech. during various phases of speech. Red Red indicates the indicates the most active areas; most active areas; blue blue indicates the least active indicates the least active areas.areas.

The Psychodynamic The Psychodynamic PerspectivePerspective• The key ideas and themes of Freud’s The key ideas and themes of Freud’s

landmark theory of psychoanalysislandmark theory of psychoanalysis continue to be important among many continue to be important among many psychologists, especiallypsychologists, especially those working in those working in the mental health field. the mental health field.

• Today,Today, psychologists who take the psychologists who take the psychodynamic perspectivepsychodynamic perspective emphasize emphasize the importance of unconscious influences,the importance of unconscious influences, early life experiences, and interpersonal early life experiences, and interpersonal relationshipsrelationships in explaining the underlying in explaining the underlying dynamics of behavior ordynamics of behavior or in treating people in treating people with psychological problems.with psychological problems.

The Behavioral The Behavioral PerspectivePerspective• Watson and Skinner’s contention that Watson and Skinner’s contention that

psychologypsychology should focus on observable should focus on observable behaviors and the fundamentalbehaviors and the fundamental laws of laws of learning is evident today in the learning is evident today in the behavioralbehavioral perspective. perspective. Contemporary psychologists Contemporary psychologists whowho take the behavioral perspective take the behavioral perspective continue to study howcontinue to study how behavior is acquired behavior is acquired or modified by environmentalor modified by environmental causes. causes.

• Many psychologists who work in the area Many psychologists who work in the area ofof mental health also emphasize the mental health also emphasize the behavioral perspectivebehavioral perspective in explaining and in explaining and treating psychological disorders.treating psychological disorders.

The Humanistic The Humanistic PerspectivePerspective• The influence of the work of Carl Rogers and The influence of the work of Carl Rogers and

Abraham Maslow continues to beAbraham Maslow continues to be seen among seen among contemporary psychologists who take the contemporary psychologists who take the humanistic perspective.humanistic perspective. The The humanistic humanistic perspective perspective focuses on the motivation of people to focuses on the motivation of people to grow psychologically,grow psychologically, the influence of interpersonal the influence of interpersonal relationships on a person’s self-concept,relationships on a person’s self-concept, and the and the importance of choice and self-direction in striving importance of choice and self-direction in striving to reach one’s potential.to reach one’s potential.

• Like the psychodynamic perspective, the Like the psychodynamic perspective, the humanistic perspective is oftenhumanistic perspective is often emphasized among emphasized among psychologists working in the mental health field. psychologists working in the mental health field.

The The humanistic perspectivehumanistic perspective focuses on the focuses on the motivation of people to grow psychologically,motivation of people to grow psychologically, the the influence of interpersonal relationships on a influence of interpersonal relationships on a person’s self-concept,person’s self-concept, and the importance of choice and the importance of choice and self-direction in striving to reach one’s and self-direction in striving to reach one’s potential.potential.

The Cognitive The Cognitive PerspectivePerspective• During the 1960s, psychology experienced a return to During the 1960s, psychology experienced a return to

the study of how mentalthe study of how mental processes influence behavior. processes influence behavior. This movement was called “theThis movement was called “the cognitive revolution” cognitive revolution” because it represented a break from traditional because it represented a break from traditional behaviorism.behaviorism. Cognitive psychology focused once Cognitive psychology focused once again on the important role ofagain on the important role of mental processes in mental processes in how people process and remember information, how people process and remember information, developdevelop language, solve problems, and think.language, solve problems, and think.

• The development of the first computers in the 1950s The development of the first computers in the 1950s contributed to the cognitivecontributed to the cognitive revolution. Computers revolution. Computers gave psychologists a new model for conceptualizinggave psychologists a new model for conceptualizing human mental processes—human thinking, memory, human mental processes—human thinking, memory, and perception could be understoodand perception could be understood in terms of an in terms of an information-processing model. information-processing model.

The Cross-Cultural The Cross-Cultural PerspectivePerspective• More recently, psychologists have taken a More recently, psychologists have taken a

closer look at how cultural factors influencecloser look at how cultural factors influence patterns of behavior—the essence of the patterns of behavior—the essence of the cross-cultural perspective. cross-cultural perspective.

• By theBy the late 1980s, late 1980s, cross-cultural psychology cross-cultural psychology had emerged in full force as large numbershad emerged in full force as large numbers of of psychologists began studying the diversity of psychologists began studying the diversity of human behavior in different culturalhuman behavior in different cultural settings settings and countries. and countries.

• In the process,In the process, psychologists discovered that psychologists discovered that some well-established psychological findingssome well-established psychological findings were not as universal as they had thought.were not as universal as they had thought.

SSocial loafingocial loafing• For example, one well-established psychological For example, one well-established psychological

finding was that people exertfinding was that people exert more effort on a task more effort on a task when working alone than when working as part of a when working alone than when working as part of a group,group, a phenomenon called a phenomenon called social loafing. social loafing. First First demonstrated in the 1970s, social loafingdemonstrated in the 1970s, social loafing has been has been a common finding in many psychological studies a common finding in many psychological studies conducted withconducted with American and European subjects. American and European subjects.

• But when similar studies were conducted withBut when similar studies were conducted with Chinese participants during the 1980s, the opposite Chinese participants during the 1980s, the opposite was found to be true. Chinese participants worked was found to be true. Chinese participants worked harder on a task whenharder on a task when they were part of a group they were part of a group than when they were working alone.than when they were working alone. These findings These findings were just the tip of the iceberg. Today, were just the tip of the iceberg. Today, psychologists arepsychologists are keenly attuned to the influence of keenly attuned to the influence of cultural and ethnic factors on behaviorcultural and ethnic factors on behavior..

The Evolutionary The Evolutionary PerspectivePerspective• The newest psychological perspective to gain The newest psychological perspective to gain

prominence is that of evolutionaryprominence is that of evolutionary psychology. psychology. Evolutionary psychology Evolutionary psychology refers to the refers to the application of the principlesapplication of the principles of evolution to of evolution to explain psychological processes and explain psychological processes and phenomena. phenomena.

• TheThe evolutionary perspective has grown out of a evolutionary perspective has grown out of a renewed interest in the work of Englishrenewed interest in the work of English naturalist naturalist Charles Darwin. Charles Darwin. Darwin’s first book Darwin’s first book on evolution, on evolution, On the OriginOn the Origin of Species by Means of Species by Means of Natural Selection, of Natural Selection, was published in 1859.was published in 1859.

The important point here is that a few thousand yearsThe important point here is that a few thousand years is is not long enough for sweeping evolutionary changes to not long enough for sweeping evolutionary changes to take place. take place. PsychologicalPsychological

processes that processes that were adaptations were adaptations to a prehistoric to a prehistoric way of life may way of life may continue to existcontinue to exist in in the behavioral the behavioral repertoire of repertoire of people today. people today. However, some of However, some of those processes those processes maymay not not necessarily be necessarily be adaptive in our adaptive in our modern worldmodern world..

The theory of evolutionThe theory of evolution• The theory of evolution proposes that the The theory of evolution proposes that the

individual members of a speciesindividual members of a species compete for compete for survival. Because of inherited differences, some survival. Because of inherited differences, some members of a speciesmembers of a species are better adapted to their are better adapted to their environment than are others. Organisms that environment than are others. Organisms that inheritinherit characteristics that increase their chances characteristics that increase their chances of survival in their particular habitatof survival in their particular habitat are more are more likely to survive, reproduce, and pass on their likely to survive, reproduce, and pass on their characteristics to theircharacteristics to their offspring. offspring.

• Conversely, individuals that inherit less-useful Conversely, individuals that inherit less-useful characteristics are lesscharacteristics are less likely to survive, likely to survive, reproduce, and pass on their characteristics. This reproduce, and pass on their characteristics. This process reflectsprocess reflects the principle of the principle of natural selection: natural selection: The most adaptive characteristics are “selected”The most adaptive characteristics are “selected” and perpetuated to the next generation.and perpetuated to the next generation.

The theory of evolutionThe theory of evolution

How is evolutionary theory applied to psychology?How is evolutionary theory applied to psychology?

• Basically, psychologistsBasically, psychologists who take the evolutionary perspective who take the evolutionary perspective assume that psychological processes areassume that psychological processes are also subject to the also subject to the principle of natural selection. principle of natural selection. A A given psychological process given psychological process exists in the form it does because it “solved a specificexists in the form it does because it “solved a specific problem problem of individual survival or reproduction recurring over human of individual survival or reproduction recurring over human evolutionaryevolutionary history.” That is, those psychological processes history.” That is, those psychological processes that helped individuals adaptthat helped individuals adapt to their environments also to their environments also helped them survive, reproduce, and pass those abilitieshelped them survive, reproduce, and pass those abilities on to on to their offspring.their offspring.

• TThe role of evolution in shaping modern psychological he role of evolution in shaping modern psychological processes,processes, keep a couple of things in mind.keep a couple of things in mind. We tend to take We tend to take the trappings of civilization—the trappings of civilization— governments, transportation governments, transportation systems, factories and manufacturing,systems, factories and manufacturing, education and education and organized medicine—for granted. But these aspects of organized medicine—for granted. But these aspects of everydayeveryday life developed only recently in the evolutionary life developed only recently in the evolutionary history of history of Homo sapiens. Homo sapiens. What weWhat we think of as human history think of as human history has existed for less than 10,000 years, since the earliesthas existed for less than 10,000 years, since the earliest appearance of agriculture.appearance of agriculture. In contrast, our evolutionary In contrast, our evolutionary ancestors spent more than ancestors spent more than 2 million years 2 million years asas hunter-hunter-gatherers. Our lives as humans living in agricultural, industrial,gatherers. Our lives as humans living in agricultural, industrial, and postindustrial societies make up less than 1 percent of the and postindustrial societies make up less than 1 percent of the time that humanstime that humans spent as hunter-gatherers. spent as hunter-gatherers.