Quiz 14: Eysencks Biologically Based Factor Theory
A.Evidence for the biological basis of personality comes from many different sources,including temperament,behavioral genetics,and brain measure research. B.First,temperament is the biologically based tendency to behave in particular ways from very early in life.In one study,for example,Janet DiPietro and her colleagues (1996) showed that fetal activity and fetal heart rate predict temperament differences over the fi rst year of life. C.Secondly,to understand how heredity affects behavior and personality,psychologists turn to the science of behavioral genetics or the scientifi c study of the role of heredity in behavior (Fuller & Thompson,1960).The extent to which a characteristic is infl uenced by genetics is known as heritability,as we saw in the McCrae and Costa chapter.Researchers use twin-adoption studies and gene-by-environment studies to study heritability. D.Thirdly,biological aspects of personality are assessed using brain imaging techniques,the two most common forms of which are the electroencephalography (EEG) and functional magnetic resonance imaging (fMRI).
A.First,psychometric evidence for the factor's existence must be established.A corollary to this criterion is that the factor must be reliable and replicable.Other investigators,from separate laboratories,must also be able to find the factor,and these investigators consistently identify Eysenck's extraversion,neuroticism,and psychoticism. B.A second criterion is that the factor must also possess heritability and must fit an established genetic model.This criterion eliminates learned characteristics,such as the ability to mimic the voices of well-known people or a religious or political belief. C.Third,the factor must make sense from a theoretical view.Eysenck employed the deductive method of investigation,beginning with a theory and then gathering data that are logically consistent with that theory. D.The fi nal criterion for the existence of a factor is that it must possess social relevance; that is,it must be demonstrated that mathematically derived factors have a relationship (not necessarily causal) with such socially relevant variables as drug addiction,proneness to unintentional injuries,outstanding performance in sports,psychotic behavior,criminality,and so on.
A.Eysenck has built his personality theory on measures of types,or superfactors.The superfactors are broader than traits,with a single trait forming a cluster of several traits.Eysenck's procedure has yielded only three general bipolar types: extraversion/introversion (E),neuroticism/stability (N),and psychoticism/superego functioning (P). B.Extraverts are sociable,impulsive,lively,quick-witted,and optimistic.They enjoy taking risks and seek other types of excitement,including stimulating social activities.Introverts are quiet,passive,unsociable,careful,reserved,thoughtful,pessimistic,peaceful,and controlled; they have a congenitally low cortical arousal level that keeps them from exciting,dangerous activities. C.High N scores are overreactive,frequently complain of vague physical symptoms,and have difficulty returning to a normal state after emotional arousal.Low N scores are emotionally stable,calm,even-tempered,and controlled. D.People who score high on P are not necessarily suffering form a psychosis,but they do have a high predisposition to develop pathology under periods of high stress. E.According to Eysenck,all three types have a strong genetic component.