Chapter 7 Physiological Approaches to Personality 1 M

Chapter 7 Physiological Approaches to Personality 1 © M. Guthrie Yarwood

Part Two. Biological Domain � Chapter 6: Do our genes influence our personality traits? � Chapter 7: Do our physiological systems (e. g. , brain, peripheral nervous system) influence our personality traits? � Chapter 8: How are personality traits adaptive (Evolutionary Theory)? 2 © M. Guthrie Yarwood

Chapter 7 Outline � Physiologically Based Theories of Personality � Eysenck’s PEN Model � Gray’s RST Model � Zuckerman’s Sensation Seeking Theory � Cloninger’s Tridimensional Personality Model � Recent Research � Gray: Neurotransmitters and Brain Structures � Frontal Asymmetry 3 © M. Guthrie Yarwood

Eysencks’ PEN Model Psychoticism 4 Extraversion © M. Guthrie Yarwood Neuroticism

Eysenck’s PEN Model: Extraversion-Introversion ARAS admits little stimulation to brain ARAS admits much stimulation to brain 5 Feel underaroused Seek stimulation in environment EXTRAVERT! Feel overaroused Do not seek stimulation in environment INTROVERT! © M. Guthrie Yarwood

EPQ-R Items � Extraversion � Are you rather lively? Are you a talkative person? � Psychoticism Would being in debt worry you? � Do you take much notice of what people think? � � Neuroticism Does your mood often go up and down? � Are you an irritable person? � � Lie If you say you will do something, do you always keep your promise no matter how inconvenient it might be? � Have you ever blamed someone for doing something you knew was really your fault? � 6 © M. Guthrie Yarwood

Eysenck’s PEN Model: Optimal Level of Arousal � Eysenck applied Optimal Level of Arousal (Hebb, 1955) to further explain differences between E and I � Level of arousal that is just right for any given task � Varies 7 by individual © M. Guthrie Yarwood

Performance Level High E I Low 8 High Level of Stimulation in Environment © M. Guthrie Yarwood

Testing PEN: � Performance � Mild Stimulation (caffeine; Bullock & Gilliland, 1993) � Moderate Stimulation (recorded traffic noise; Belogevic et al. , 2001) � Alpha Activity (measures low-levels of arousal; Gale, 1983) �I showed greater alpha activity than E. � Other 9 studies: No differences in resting arousal © M. Guthrie Yarwood

I/E, Music, and Performance � Music IV Conditions � No Music � High Complexity Instrumental � Low Complexity Instrumental � Personality (PEN): Introverted, Extraverted � DV = reading comprehension � Results � Extravert/Introvert performance not affected by music condition � Other 10 Research found effects for I © M. Guthrie Yarwood

Eysenck’s PEN Model: Testing theory � No difference in resting levels � Introverts ARE more reactive to moderate levels of stimulation than extraverts � Eysenck Revised – it’s arousability, not resting arousal! 11 © M. Guthrie Yarwood

Match the Big Five Factors to the PEN factors! Extraversion Psychoticism Extraversion Neuroticism Conscientiousness Agreeableness Neuroticism 12 Openness to Experience © M. Guthrie Yarwood

Gray’s RST Theory: Sensitivity to Reward and Punishment � 3 1. 2. 3. Neural Systems Behavioral Activation System (BAS) Behavioral Inhibition System (BIS) Fight-Flight-Freeze System (FFFS; previously, FFS) � Textbook: explains Gray’s original RST theory (Gray, 1972, 1975, 1990) � We will discuss his revised theory (Gray, & Mc. Naughton 2000) 13 © M. Guthrie Yarwood

Gray’s RST Theory: Individual Differences in 3 Systems BAS BIS FFFS 14 • IMPULSIVITY • Motivate people to approach rewarding stimuli • ANXIETY • During goal conflict, activates BAS or FFFS • FEAR • Motivate people away from danger © M. Guthrie Yarwood

3 Types of Goal Conflict � Approach-Approach � Choose between 2 desirable goals � Avoidance-Avoidance � Choose between two undesirable goals � Approach-Avoidance � Same 15 goal is desirable and undesirable © M. Guthrie Yarwood

Gray’s RST Theory: BIS Resolves Approach. Avoidance Goal Conflict Reward > Threat BIS engages BAS and inhibits FFFS Approach Behavior Conflict Resolved! 16 © M. Guthrie Yarwood

Gray’s RST Theory: BIS Resolves Approach. Avoidance Goal Conflict Threat > Reward BIS engages FFFS and inhibits BAS Avoidance Behavior Conflict Resolved! 17 © M. Guthrie Yarwood

Gray’s RST Theory: Physiological Systems BAS BIS FFFS 18 • Greater left front cortical activity • Cerebral cortex, thalamus, striatum • Greater right front cortical activity • Brain stem, frontal lobe • Sympathetic nervous system © M. Guthrie Yarwood

Frontal Asymmetry: Does greater activation on one side of the frontal lobe explain individual differences in personality? 19 © M. Guthrie Yarwood

Right Frontal Lobe = More behavioral avoidance than behavioral activation Left Frontal Lobe = More behavioral activation than behavioral avoidance Approach! Avoid! Extraversion Neuroticism BAS BIS 20 (Davidson 2002; Harmon-Jones & Allen, 1998 Zuckerman, 2005) © M. Guthrie Yarwood

How does this relate to mental illness? � Left Asymmetry / BAS Activation � Impulsive, � Right Asymmetry / BIS Activation � Anxiety, 21 over-reactive to rewards over-reactive to punishers © M. Guthrie Yarwood

High BIS? Low BIS? High BAS? Low BAS? �Anxiety Disorders �Obsessive-Compulsive Disorder �Bipolar Disorders �ADHD �Conduct Disorder �Substance Abuse �Histrionic Personality Disorder �Avoidant Personality Disorder �Dependent Personality Disorder 22 © M. Guthrie Yarwood

Gray’s RST Theory: Bringing It Together High BAS High BIS � Extraversion � Neuroticism � Positive � Negative Emotions � Impulsive; over-reactive to rewards � Externalizing Disorders 23 Emotions � Anxiety; Overreactive to punishers � Internalizing Disorders © M. Guthrie Yarwood

Zuckerman: Sensation Seeking � Tendency to seek out thrilling, exciting activities, take risks, avoid boredom � High sensation seekers: � less tolerant of sensory deprivation � Require much stimulation to reach optimal level of arousal � High need for stimulation in their daily lives � Zuckerman’s � 4 24 Sensation Seeking Scale-V (SSS-V) Factors © M. Guthrie Yarwood

(Factors) 25 © M. Guthrie Yarwood

High or Low Sensation Seeking? � Young or old? � Whites or Blacks? � Religious or Not Religious? � College or High School Degree? � Divorced 26 or Married? � Wisconsin � US or California? or France? � Saudi Arabia or Mexico? � Firstborns � Bipolar or laterborns? or Antisocial? © M. Guthrie Yarwood

Sensation Seeking by US State � http: //buzz. drkencarter. com/chart. html 27 © M. Guthrie Yarwood

Zuckerman: Sensation Seeking and MAO � Physiological basis for sensation seeking � Monoamine Oxidase (MAO) � Enzyme that maintains a proper level of neurotransmitters � Too little MAO = too much neurotransmitter � Too much MAO = too little neurotransmitter � Negative 28 Correlation b/w MAO level and SS © M. Guthrie Yarwood

Zuckerman: Sensation Seeking and MAO � High sensation seekers have low levels of MAO, � The low MAO, leads to less inhibition of other neurotransmitters � Results in less control over behavior, thoughts, emotions 29 © M. Guthrie Yarwood

Problems with measure? (Y/N Response) � TAS: �I prefer the surface of the water to the depths � I would like to go scuba diving. � ES �I dislike all body odors. � I like some of the earthy body smells. � DIS �I dislike “swingers” (people who are uninhibited about sex) � I enjoy the company of real “swingers” � BS � The worse social sin is to be rude. � The worst social sin is to be a bore. 30 © M. Guthrie Yarwood

Zuckerman: Sensation Seeking and Big Five Extraversion Openness to Experience TAS ES Dis BS . 30 ― ― ― . 50 ― ― ― SSS. 34. 37 Note. NEO-PI-R used for Big Five measures 31 (Aluja, García, © M. Guthrie Yarwood & García, 2003)

Overview: Neurotransmitters and Personality � Individuals differences in levels of neurotransmitter cause individual differences in personality. 32 Dimension Level of Neurotransmitter Novelty Seeking High Dopamine Harm Avoidance Abnormalities in serotonin. Reward Dependence Low Norepinephrine © M. Guthrie Yarwood

Cloninger’s Tridimensional Personality Model Dimension Description Novelty Seeking (Active Dopamine) Individual differences in excitability, impulsiveness, extravagance, disorderliness Individual differences in worry, pessimism fear, shyness, fatigability; tendency to avoid pain and anxiety Harm Avoidance (Inactive Serotonin) Low = energetic, outgoing, optimistic High = cautious, inhibited, shy, apprehensive; expect to experience unpleasant events Reward Dependence (Inactive Norepinephrine) 33 Individual differences in sentimentality, warm communication, dependence; tendency to develop strong emotional attachments; persistent in behaving in ways that produce reward. © M. Guthrie Yarwood

Active Dopamine Inactive Serotonin Inactive Norepinephrine ↑ Response to pleasurable, exciting stimuli ↑ Response to harmful, unpleasant stimuli ↑ Response to stimuli previously associated with pleasure High Novelty Seeking High Harm Avoidance High Reward Dependence 34 © M. Guthrie Yarwood

Gray’s Recent Research (De. Young & Gray, in press) Higher Levels of: O Serotonin Dopamine C E + + A N + — + Testosterone + — Norepinephrine + Oxytocin/ Vasopressin Blood Glucose 35 + + © M. Guthrie Yarwood

36 © M. Guthrie Yarwood

Gray’s Recent Research (De. Young et al. , 2010) Big Five Trait Brain Structure Corr. w/ Volume C Lateral prefrontal cortex + Keeping info in working memory and executing planned action E Medial orbitofrontal cortex + Processes info about rewards A Cingulate cortex + Increased ability to understand others’ thoughts (i. e. theory of mind) — Sensitivity to threat and punishment, increased tendency to experience negative emotion; reduced ability to regulate emotions. N 37 Prefontal cortex; hippocampus Why? © M. Guthrie Yarwood

Summary: Neurotransmitters and Personality � Gray’s theory links individual differences in personality to � individual differences in levels of neurotransmitters and � Individual differences in the volume of brain structures � Frontal asymmetry is a promising area of research for individual differences in personality � Left-Dominant = tendency to approach � Right-Dominant = tendency to avoid 38 © M. Guthrie Yarwood

Summary and Evaluation � Study of personality can be approached biologically � Two ways to think about how physiological variables are useful in personality theory and research… � Use physiological measures as variables that may be correlated with personality traits � View physiological events as providing causal substrate for personality trait 39 © M. Guthrie Yarwood