Personality psychology chapter7 biological processess and personality

Chapter Seven Biological Processes and Personality Extraversion • Hans Eysenck—level of extraversion/ introversion reflects differences in cerebral cortex activation • Introverts Extraverts – Higher basal cortical activation •Lower basal cortical activation – More alert when nothing happening •Less alert when nothing happening – Withdraw to avoid overstimulation • Seek stimulation to elevate arousal – Fewer mistakes on tasks requiring •More bored by repetitive tasks vigilance – Require more depressant drugs to •Require more stimulants to reach reach given index of unalertness given level of arousal Neuroticism • High neuroticism reflects easily aroused emotion centers in the brain – Emotional arousal exaggerates behavioral responses of introverts and extraverts Behavioral Approach System (BAS) • Regulates movement toward desired states or objects (incentive) • Responsible for positive emotions (left prefrontal cortex) • Relates to conditioning involving positive outcomes, but not negative outcomes • People with different levels of BAS sensitivity demonstrate differences in behavioral and emotional responses to incentives • May be related to dopamine activity Behavioral Inhibition System (BIS) • Regulates movement away from undesired states or objects • Associated with anxiety (right prefrontal cortex) • Relates to conditioning involving negative outcomes, but not positive outcomes • People with different levels of BIS sensitivity demonstrate differences in behavioral and emotional responses to punishment • May be related to serotonin and/or GABA activity Approach/Inhibition and Traits • BIS-related neuroticism/emotionality – Anxiety at core of emotionality – High BIS-sensitive people respond to anxiety manipulations • BAS-related to extraversion – High BAS-sensitive people respond to positive mood manipulations Areas of Disagreement • Social qualities of extraversion? – Perhaps it’s useful to think of social incentives as an important class of rewards to which extraverts are drawn in order to experience positive affect • Role of impulsivity – Is it linked to extraversion? – Is it a separate trait (the flip-side of conscientiousness)? – Another view—impulsivity with positive affect belongs with extraversion – Impulsivity items not load with BAS or extraversion items in a factor analysis Sensation Seeking • Marvin Zuckerman • High sensation seekers are in search of new, varied, and exciting experiences – – – – – – Drive faster More likely to use drugs and increase alcohol use over time More high-risk sports More risky antisocial behavior More sexually experienced and responsive More dissatisfied with relationships • Monoamine Oxidase (MAO) – Related to levels of sensation seeking – Also associated with social dominance, aggression, and gene linked to impulsivity Function of Sensation Seeking • Regulates exposure to stimulus intensity – High sensation seekers (HSS) open themselves up to stimulation – HSS well in overstimulating conditions – Low sensation seekers (LSS) adapt better to most ordinary circumstances, but may shut down under intense conditions – Impulsive unsocialized sensation seeking (IUSS) —inability to inhibit behavior appropriate to social constraints Impulsiveness • Issue: How best to account for impulsiveness • Approach and inhibition systems – High BAS – Low BIS – Combination (high BAS and low BIS) • Serotonin – Most studies relate serotonin to negative emotion – Low serotonin function associated with anger, impulsive aggression – Serotonin levels positively related to conscientiousness – Suggestive that impulsiveness derives from a separate biological system Hormones and Personality • Testosterone: – Higher prenatal levels weeks 8-24, months 1-5 after birth, and after puberty for normal males – Developmental default is female – Exposure to androgens results in male physical and neurological development – Exposure to higher levels of prenatal androgens: • Associated with higher self-reported physical aggression scores in response to hypothetical situation (boys and girls) • Associated with cross-gender toy selection among girls Testosterone and Adult Personality • Focus on associations with dominance and antisocial behavior – Positive associations with: • Violation of prison rules among inmates and likelihood of having committed violent crime • Veterans’ trouble with parents, teachers, and classmates when growing up (increased effects among low SES) • Being a trial lawyer, actor, NFL football player • More dominant and confident social interactions • Not being married, getting divorced, having an affair, and domestic abuse among men – Factor analysis with personality items—testosterone data loaded with impulsiveness, sensation seeking, and dominance Cycles of Testosterone Action • Testosterone rises after: – Success in a competitive event – Your team wins – Sexual intercourse – Challenged by insult • Testosterone falls after: – Failure or humiliation – Your team loses Testosterone, Dominance, and Evolutionary Psychology • Males: Overt aggressiveness helps confer dominance and status increasing reproductive advantage • Females: No advantage for aggressiveness in females and may interfere with reproductive success and child rearing activities • Irony: In today’s society, dominance and status are defined in greater socioeconomic terms High levels of testosterone may interfere with socioeconomic advancement Men, Women, and Oxytocin • In response to threat, animals engage “fight or flight” response – Most research demonstrating this effect was done with males • Different response may be activated for females—“tend and befriend” – Reflects differing evolutionary pressures on males and females due to offspring investment (i.e., not effective to fight when pregnant or caring for an infant) – Derived from systems that produce bonding between infant and caregiver • Oxytocin—hormone resulting in relaxation, calming, motherinfant bonding, general social bonding, and adult pairbonding in some species – Females typically have higher levels than men – Androgens inhibit release of oxytocin under stress; estrogens activate release – Released during orgasm, childbirth, massage, and breast-feeding Assessment • Assessment tied to biological processes – EEG—measures of electrical brain activity – PET—mapping of brain activity from metabolic function – MRI—images of brain function from magnetic fields created from neural activity • Functional MRI—assesses levels of activation at rest and during mental activity Problems in Behavior • Anxiety—indicative of oversensitive BIS activity • Depression – High BIS activity – Weak BAS activity • Antisocial personality – High BAS activity – Low BIS activity – Third system—sensation seeking, low MAO, high testosterone Therapy • Modifying biological function may change manifestation of disorders • Pharmacotherapy—drug administration – Antianxiety drugs – Antidepressants (SSRIs) • If drug therapy changes personalities, what are the implications for the way we view the construct? ... impulsiveness derives from a separate biological system Hormones and Personality • Testosterone: – Higher prenatal levels weeks 8-24, months 1-5 after birth, and after puberty for normal males –... hypothetical situation (boys and girls) • Associated with cross-gender toy selection among girls Testosterone and Adult Personality • Focus on associations with dominance and antisocial behavior –... Dominance, and Evolutionary Psychology • Males: Overt aggressiveness helps confer dominance and status increasing reproductive advantage • Females: No advantage for aggressiveness in females and may