Hockenbury Discovering Psychology 5th txtbk

The Trait Perspective on Personality443FOCUS ON NEUROSCIENCEPersonality Traits and Patterns of Brain ActivityPeople who rate high on the personality trait of extraversion tendto be upbeat, optimistic, and sociable. They also report experiencingmore positive emotions on a daily basis than less extra -verted people. In contrast, people who rate high on neuroticismtend to be anxious, worried, and socially insecure. And theyreport more negative emotions in everyday life than less neuroticpeople. Could these personality traits also influence how thebrain responds to emotional situations?To investigate this idea, psychologist Turhan Canli and his colleagues(2001) gave 14 healthy female volunteers a personalitytest to determine their level of extraversion or neuroticism. Then,each woman was placed in a functional magnetic resonanceimaging (fMRI) scanner to record her brain’s reaction to positiveimages (e.g., a happy couple, puppies, ice cream, sunsets) or negativeimages (e.g., angry or crying people, spiders, guns, or acemetery).The fMRI showed that the women who scored high on extraversionhad greater brain reactivity to positive images than did thewomen who scored low on extraversion. In image (a), red locationsshow significant positive correlations between extraversion andreactions to positive images. For the extraverted women, brainactivity in response to the positive images was most stronglycorrelated with brain areas associated with emotion, includingthe frontal cortex and the amygdala.In contrast, the women who scored high on neuroticism hadmore brain activation in response to negative images, but infewer brain areas associated with emotions. In image (b), bluelocations show significant positive correlations between neuroticismand reactions to negative images. These areas of activationwere mostly in the left frontal and temporal cortical areas.What this study shows is that specific personality traits areassociated with individual differences in the brain’s reaction toemotional stimuli. According to researcher John Gabrieli (2001),“Depending on personality traits, people’s brains seem to amplifysome aspects of experience over others. All of the participants inthis study saw very positive and very negative scenes, but people’sbrain reactions were very different. One group saw the cup asbeing very full while the other group saw it as very empty.”(a) Extraversion correlating with brain reactivity to positive pictures(b) Neuroticism correlating with brain reactivity to negative picturesKeep in mind, however, that human behavior is the result of a complex interactionbetween traits and situations (Mischel, 2004). People do respond, sometimesdramatically, to the demands of a particular situation. But the situations that peoplechoose, and the characteristic way in which they respond to similar situations, arelikely to be consistent with their individual personality dispositions (Mischel &Shoda, 1995; Mischel & others, 2002).Personality Traits and Behavioral GeneticsJust a Chip off the Old Block?Do personality traits run in families? Are personality traits determinedby genetics? Many trait theorists, such as Raymond Cattelland Hans Eysenck, believed that traits are at least partially geneticin origin. For example, our daughter, Laura, has always been outgoingand sociable, traits that she shares with both her parents.But is she outgoing because she inherited that trait from us? Or isshe outgoing because we modeled and reinforced outgoing behavior?Is it even possible to sort out the relative influence that geneticsand environmental experiences have on personality traits?The Continuity of Traits overthe Life span Kenneth’sconscientiousness was a traitthat was evident throughouthis life. Because he was tooold to join the military whenthe United States enteredWorld War II, Kenneth volunteeredhis legal expertise tothe American Red Cross,providing them with legalservices for the western halfof the United States.