Physiological Perspective

Physiological Perspective Types of measures Sampling of Research Topics Eysenck, Gray: Extraversion Zukerman: Senation-Seeking Cloninger: Neurotransmitters Davidson: Brain Asymmetry Amodio: Political Brain

Phineas Gage (1850s) Dynamite accident Changes in personality Frontal lobe insights Executive functions Emotion regulation Impulsivity, planning

Orbital-frontal Cortex

Dorsolateral Prefrontal Cortex

Anterior Cingulate Cortex

3 Frontal Lobe Clinical Syndromes Dorsolateral (Cognition) Working memory, decision-making, reasoning Orbital-frontal (Emotion) irritabilty, anger, low empathy Anterior Cingulate (Motiv) apathy

ADD Symptom Clusters Attention deficit Impulsivity Concentration problems Easily distracted Sloppy, disorganized Impulsivity Get into fights Stubborn, strong-willed 3) Emotion disregulation feel guilty, feel angry

ADD relation to Big Five

ADD relation to Big Five M ADHD Controls

Amygdala Hippocampus Basal Ganglia Accumbens Hoogman et al. (2017) Brain Volume and ADHD Hoogman et al. (2017) Amygdala Hippocampus Basal Ganglia Accumbens Meta-analysis of approx 3,000 (half controls, half persons diagnosed with ADHD) individuals. Main finding was reduced size in several subcortical brain regions.

170 AD: Galen’s 4 Humors Blood sanguine happy Bodily fluids  personality (170 AD) (Hippocrates, 400BC) Phlegm phlegmatic calm Blood sanguine happy Yellow Bile choleric excitable Black Bile melancholy unhappy

1809 Phrenology: Francis Gall Traits=bumps Bump=more brain tissue Pseudoscience Brain? Localization of of function—yes. Cranial bumps? Wrong.

Sheldon’s Somatotype Theory (1940s) Body shape  personality Mesomorph Athletic Dominant Ectomorph Slight Introverted Endomorph Rotund Jolly

Physiological Measures Polygraph “Meet the Fockers” (2004)

Electrodermal Activity (EDA) Derma= skin Sweat conducts electricity (“GSR”) Sweating due to Sympathetic Arousal Emotional arousal (pain, anxiety, fear, guilt…) Elevated baseline EDA & personality: Neuroticism

Lying & Sympathetic Arousal Ancient Arabia lick hot iron… if burn tongue, you are lying. Ancient China & India chew rice powder, spit out… if dry, you are lying. Sympathetic arousal inhibit digestion (e.g. saliva  ) activate metabolism respiration  heart rate  ventilation 

Cardiovascular activity Blood pressure —measure of stress reactivity Heart rate —increases with anxiety, fear, arousal, cognitive effort

Cardiovascular activity Cardiac reactivity greater than normal increase in blood pressure and heart rate in response to a challenge Associated with Type A personality: (impatient + competitive + angry/hostile) Cardiac reactivity & Type A is associated with elevated risk of coronary heart disease

Brain Activity Brain spontaneous electrical activity Measure by electrodes on scalp (EEG) Evoked Potential technique Stimulus given, EEG measured Evoked Auditory Potential (Auditory stimuli) Evoked Visual Potentials (Visual Stimuli) Waves patterns analyzed Augmenting vs Reducing

P300 a positive electrical potential that reliably occurs 300 milliseconds after a stimulus

P300 Discovered in 1964 “Context updating” signature Schizophrenia - weak (abnormal amplitude) Borderline Disorder - delayed (abnormal latency)

P300 impulsiveness - longer latency creativity, openness, curiosity “need for cognition” (intellectual curiosity) - higher amplitude P300a  novelty orienting P300b  surprise orienting

Brain Imaging Mapping brain structure and function Positron emission tomography (PET) Functional magnetic resonance imaging (fMRI) Deffusion Tensor Imaging neural connectivity, mapping circuits

Canli et al (2001), fMRI E: +pics N: -pics

De Young et al. (2010)

Positron Emission Tomography

Neuroscience of extraversion Johnson et al. (1999) PET 9 low (I), 9 high (E) resting state only RESULTS Thalamus I: ↑ Anterior, E: ↑ posterior Insula I: ↑ Anterior, E: ↑ posterior Broca’s Area I > E ( talking to yourself !!) JOHNSON ET AL 1999 18 healthy Ss (aged 19-48 yrs) positron emission tomography. Correlations of regional CEREBRAL BLOODFLOW with introversion/extraversion were calculated, and a three-dimensional map of those correlations was generated. introversion was associated with increased blood flow in the frontal lobes and in the anterior thalamus. anterior cingulate gyrus, the temporal lobes, and the posterior thalamus = extraversion. The findings of the study lend support to the notion that introversion is associated with increased activity in frontal lobe regions. Moreover, the study suggests that individual differences in introversion and extraversion are related to differences in a fronto-striato-thalamic circuit. Gale (46) speculated that introverts might engage in a running monologue in the absence of external stimulation. The observed increased blood flow in Broca’s area in introverts might be interpreted as biological evidence of “self-talk.” blood flow in the anterior insula is correlated with introversion, whereas blood flow in the posterior insula is correlated with extraversion.Recent studies of emotion have found that the anterior portion of the insula is activated when subjects recall or imagine events, whereas the posterior insula is activated by interpretation of current sensory information (49, 50). The distinction between an inward focus And an outward focus is very much the difference between introverts and extraverts.

Neuroscience of spiritual feelings Borg et al. (1999)

Neuroscience of spiritual feelings Borg et al. (1999) Measured “self-transcendence” Measured serotonin receptor density Conclusions Weak serotonin binding Weak gating of sensory stimuli [?]

Other Physiological Measures Blood-born metabolites Monoamine Oxidaze (MAO) Immune system (e.g., saliva swabs) e.g. Master et al. (2009) . . . “Emotional Approach”

Emotional Approach Scale Master et al. (2009) After a profoundly upsetting event, I take time to figure out what I’m really feeling In especially trying circumstances, I delve into my feelings to get a thorough understanding of them When dealing with unusual challenges, I realize that my feelings are valid and important When coping with a really stressful experience, I acknowledge my emotions

Masters et al. (2009) Higher scores on the emotional approach scale significantly predicted… Stronger immune response to laboratory stressor (physiological challenge) Reduced recovery time after heart surgery

Other Physiological Measures Cortisol Kagan & Snidman (1991) Testosterone (Ts) Dabbs & Dabbs (2000) “crafty”, “sly”, “manipulative”

Hormones and Personality Gender differences in personality Agreeableness (d=.50) Neuroticism (d=.50) Large gender differences in testosterone Indivdual differences in testosterone within sex aggressiveness ??

Testosterone and dominance Masur et al, 1992 Post-victory surge High Ts Jobs: Trial Lawyer Actors Athletes High Ts traits Boastful, arrogant, devious

Testosterone and 2D:4D Fetal testosterone levels influence length of third finger. Estrogen influences length of first finger. Adult digit ratio is useful in research as a proxy for fetal Ts exposure levels Gender differences exist in 2D4D: lower ratio in men.

Meindl et al. (2012) Testosterone and 2D:4D 2D4D is correlated with adult facial masculinity. 17 boys, aged 3-11. Facial dimensions recorded. Data used to construct computer model of 2D4D effects on facial shape.

Meindl et al. (2012) 2D:4D

Testosterone and 2D:4D Most consistent personality correlates of Low 2D4D: Sensation-Seeking Impulsiveness Aggression Interpersonal dominance / boldness Psychopathy However, the associations are typically not very strong in magnitude and often fail to replicate.

Physiological Perspective Measures Theories Eysenck, Gray: Extraversion Zukerman: Senation-Seeking Oxley / Amodio: Political Brain Cloninger: Neurotransmitters Davidson: Brain Asymmetry

Physiological-Based Dimensions of Personality Extraversion-Introversion Eysenck’s Theory: Introverts are characterized by higher levels of activity in the brain’s ascending reticular activating system.  ARAS

Ascending Reticular Activating System 1950s: ARAS controls amount of Cortical Arousal

Yerkes-Dodson Law: Optimal Arousal for a Task

Extraversion-Introversion When given a choice, extraverts prefer higher levels of stimulation than introverts Classic study by Russ Geen (1984) Compared Extrav (E) and Introv (I) Noise level preferences Autonomic reactvity

Geen (1984) Learning task Distracting noise over headphones Hi E, Low E subjects Noise level chosen by Self, Intr, Extr Measure stress reactions (physio)

Extraversion-Introversion Geen (1984) Introverts and extraverts perform task… Best under their own chosen stimulation level Poorest under level chosen by opposite personality

Eysenck’s Theory of E No baseline differences in arousal. Revised theory: Extraversion-Introversion= Differences in arousal reactivity, not average levels of arousal

Reinforcement Sensitivity Theory (Gray, 1972; 1990) Jeffrey Gray, biopsychologist (rats) Alternative theory of Extr and Neur Focuses on two different brain systems: Beh Activation System BAS Beh Inhibition System BIS

Approach Avoidance

Sensitivity to Reward and Punishment Behavioral Activation System (BAS): Sensitive to reward cues Activate/Energize/Get Personality? impulsive Behavioral Inhibition System (BIS) Sensitive to threat cues Inhibit/Stop/Evaluate Personality? Anxious

Integration of Gray and Eysenck theories Impulsive =High extraversion, moderate neuroticism Anxious =Moderate introversion, high neuroticism

Gray’s Rotation of Eysenck BAS BIS N E

But data supports a closer alignment to Eysenck BIS N BAS E

Larsen, Chen, Zelenski (2003) Learning task (fast colour naming) Manipulate type of trial feedback: Punishment for wrong answer Reward for correct answer Measure BAS and BIS traits. RESULT? BIS people did better in punishment condition BAS people did better in reward condition

Size of bets placed after punishment vs reward Pierce-McCall & Newman (1986) IV= won versus lost. DV= Size of bet on next task. Result: After gain: E = I After loss: E > I

Physiological Perspective Measures Theories Eysenck, Gray: Extraversion Zukerman: Senation-Seeking Oxley / Amodio: Political Brain Cloninger: Neurotransmitters Davidson: Brain Asymmetry

Sensation Seeking Marvin Zuckerman 1970s-80s Sensory deprivation studies: Extraversion Hebb’s Optimal Level of Arousal theory SSSK =Diff in optimal level of arousal Zuckerman’s Sensation Seeking Scale Moderate positive correlation between extraversion and sensation seeking

Boredom Susceptibility Thrill and Adventure Seeking Sensation-seeking 4 factors (DEBT) Disinhibition Experience-Seeking Boredom Susceptibility Thrill and Adventure Seeking

Sensation Seeking Physiological basis for sensation seeking Monoamine Oxidase (MAO) Enzyme that regulates neurotransmitters After neurotransmitter binds to receptor need to stop it somehow MAO puts the brakes on (at the receptor)

Sensation Seeking Physiological basis for sensation seeking Too much MAO= strong braking Too little MAO= weak braking High SSK have low MAO Stimulation seeking is due to weak synaptic braking

Cortical Evoked Potentials and Sensation-Seeking Augmenting is evident among high SSkers Reducing is evident among low SSkers

MAO, Child Abuse, and Antisocial Tendencies Interaction of gene and child maltreatment experiences Low MAO + maltreatment= high risk to become antisocial Caspi et al (2002)

Physiological Perspective Measures Theories Eysenck, Gray: Extraversion Zukerman: Senation-Seeking Oxley / Amodio: Political Brain Cloninger: Neurotransmitters Davidson: Brain Asymmetry