Personality psychology chapter7 biological processess and personality

Behavioral Approach System BAS• Regulates movement toward desired states or objects incentive • Responsible for positive emotions left prefrontal cortex • Relates to conditioning involvi

Chapter Seven

Biological Processes and

Personality

Biological Processes and

Personality

• Hans Eysenck—level of extraversion/

introversion reflects differences in cerebral

cortex activation

–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

–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

• 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 do 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 do 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

• 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)

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

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, mother-infant bonding, general social bonding, and adult

pair-bonding 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 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

• 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?