PHYSIOLOGY AND PERSONALITY MEASURES THEORY Cato Grønnerød PSY FYSIOLOGI OG PERSONLIGHET MÅLING TEORIER Cato Grønnerød PSY1006 FYSIOLOGISK TILNÆRMING Hjernefunksjon • Temporallappene • Nevrotransmittere Autonome nervesystem • Sympatiske og parasympatiske systemer Hormonelt system • Kjønnshormoner • Adrenalin, kortisol Eksterne agenter SHELDON’S PHYSIOLOGICAL APPROACH TO PERSONALITY Argued that body type determines personality Did not use blind ratings, most later research failed to replicate Some work suggesting relationship between body type and job choice Physiological personality psychologists today do not focus on global variables such as body type © 2008 The McGraw-Hill Companies, Inc. All rights reserved. HISTORISKE TEORIER Kroppsvæsker (Galen) • • • • Flegmatisk: passiv, rolig, tankefull Sangvinsk: glad, utadvendt og livlig Kolerisk: ustabil, aggressiv og oppfarende Melankolsk: nedstemt og pessimistisk Kroppstyper (Sheldon) • Ektomorf: intelligente, fryktsomme • Mesomorf: populære, hardtarbeidende • Endomorf: glade, late, skjødesløse PHYSIOLOGICAL MEASURES COMMONLY USED IN PERSONALITY RESEARCH Electrodermal Activity (Skin Conductance) Cardiovascular activity Brain Activity Other measures: Biochemical analyses of blood and saliva © 2008 The McGraw-Hill Companies, Inc. All rights reserved. FYSIOLOGISKE MÅLINGER Hudmotstand (Skin Conductance, Electrodermal Activity) • Elektroder eller sensorer på huden Kardiovaskulær aktivitet • Blodtrykk, puls Hjerneaktivitet • Elektroencefalografi, fMRI, PET Biokjemiske analyser av blod og slim ELECTRODERMAL ACTIVITY (EDA): SKIN CONDUCTANCE Most obtained by electrodes or sensors placed on the skin surface Advantage: Noninvasive, no discomfort Disadvantage: Movement constrained © 2008 The McGraw-Hill Companies, Inc. All rights reserved. ELECTRODERMAL ACTIVITY (EDA): SKIN CONDUCTANCE Electrodermal activity—due to increased sweat with arousal, skin conductance of electricity increases Can measure responses to various stimuli, including sudden noises, emotionally charged pictures, pain, anxiety, fear, guilt Some people show EDA in the absence of external stimuli—associated with anxiety and neuroticism © 2008 The McGraw-Hill Companies, Inc. All rights reserved. HUDMOTSTAND (EDA) Aktivering av autonomt nervesystem • -> økt aktivitet i svettekjertlene • -> økt mengde saltvann • -> økt ledbarhet for strøm Responser til forskjellige stimuli • Fight or flight-respons • Plutselige lyder, emosjonelt ladede bilder, smerte, angst, frykt, skyldfølelse HUDMOTSTAND (EDA) EDA i fravær av eksterne stimuli • Angst og nevrotisisme • Fortrengning, ubevisste prosesser? Fordeler • Ikke-invaderende • Kjenner ingenting Ulemper • Begrenset bevegelighet • ”Påklistret” følelse CARDIOVASCULAR ACTIVITY Blood pressure—measure of, e.g., stress reactivity Heart rate—increases with anxiety, fear, arousal, cognitive effort © 2008 The McGraw-Hill Companies, Inc. All rights reserved. CARDIOVASCULAR ACTIVITY Cardiac reactivity—greater than normal increase in blood pressure and heart rate when performing task such as backward serial subtraction • Associated with Type A personality—impatience, competitiveness, hostility • Cardiac reactivity (and Type A) associated with coronary heart disease © 2008 The McGraw-Hill Companies, Inc. All rights reserved. KARDIOVASKULÆR AKTIVITET Blodtrykk • Diastolisk trykk: mellom hjerteslag • Systolisk trykk: maksimum trykk ved hjerteslag • Øker ved stress Puls • Øker ved fight-flight-aktivering • angst, frykt, generell aktivering KARDIOVASKULÆR AKTIVITET Hjertereaktivitet • Både blodtrykk og puls øker ved kognitive anstrengelser • Særlig koblet med stress Type A-personlighet • Fiendtlighet, utålmodighet, konkurranseinnstilling • Øker risiko for hjerteproblemer BRAIN ACTIVITY Brain spontaneously produces small amounts of electrical activity; can be measured by electrodes on scalp— electroencephalograph (EEG) Evoked potential technique—uses EEG, but the participant is given a stimulus and the researcher assess specific brain response to stimulus © 2008 The McGraw-Hill Companies, Inc. All rights reserved. BRAIN ACTIVITY Brain imaging techniques—map structure and function of brain • Positron emission tomography (PET) • Functional magnetic resonance imaging (fMRI) © 2008 The McGraw-Hill Companies, Inc. All rights reserved. HJERNEAKTIVITET EEG: elektroencefalogram • Elektroder som registrerer små elektriske signaler i hjernen • Aktivitetsmønstre i forskjellige deler av hjernen • Evoked potential: reaksjoner på stimulering PET: Positron Emission Tomography fMRI: Functional Magnetic Resonance Imaging HJERNEAKTIVITET Canli et al. (2001) • fMRI mens personer så på positivt og negativt emosjonelt ladede bilder • Nevrotisisme korrelerte med økt aktivering i temporallappene ved negative bilder • Ekstroversjon korrelerte med økt aktivering i temporallappene ved positive bilder ANDRE FYSIOLOGISKE MÅL Immunsystem • Endres ved stress og emosjoner Testosteron • Uhemmede, aggressive og risikofylte atferdsmønstre Kortisol • Høyere nivåer hos sjenerte barn MAO: Monoaminoksidase • Sensation Seeking PHYSIOLOGICALLY BASED THEORIES OF PERSONALITY Extraversion-Introversion Sensitivity to Reward and Punishment Sensation Seeking Neurotransmitters and Personality Morningness-Eveningness Brain Asymmetry and Affective Style © 2008 The McGraw-Hill Companies, Inc. All rights reserved. FYSIOLOGIBASERTE FORSKJELLER FYSIOLOGIBASERTE PERSONLIGHETSTEORIER Ekstroversjon-Introversjon Sensitivitet for belønning og straff Sensation Seeking Nevrotransmittere og personlighet A- og B-mennesker Hjerneasymmetri og affektiv stil EXTRAVERSION-INTROVERSION Measured by Eysenck Personality Questionnaire (EPQ) High extraversion: Talkative, outgoing, likes meeting new people and going to new places, active, bored easily, hates routine Low extraversion: Quiet, withdrawn, prefers being alone or with a few friends to large crowds, prefers routines, prefers familiar to unexpected © 2008 The McGraw-Hill Companies, Inc. All rights reserved. EKSTROVERSJON – INTROVERSJON Eysenck Personality Questionnaire (EPQ) Høy ekstroversjon • Snakkesalig, utadvendt, liker sosiale sammenhenger og nye steder, aktiv, kjeder seg lett, hater rutine Lav ekstroversjon (Introversjon) • Stille, tilbaketrukket, foretrekker å være alene eller med få venner, liker rutiner og det kjente frafor det ukjente EYSENCK’S THEORY Introverts have a higher level than extraverts of activity in the brain’s ascending reticular activating system (ARAS) People strive to keep ARAS activity at optimal level—introverts work to decrease and avoid stimulation; extraverts work to increase and seek out stimulation EYSENCKS TEORI Introverte har et høyere aktiveringsnivå i retikulærsubstansen (RS) enn ekstroverte Forsøker å holde ARAS-aktivitet på et optimalt nivå • Introverte demper og unngår stimulering • Ekstroverte øker og søker stimulering EYSENCK’S THEORY Research indicates that introverts and extraverts are NOT at different resting levels, but introverts ARE more reactive to moderate levels of stimulation than extraverts This work led Eysenck to revise his theory—the difference between introverts and extraverts lies in arousability, not in baseline arousal © 2008 The McGraw-Hill Companies, Inc. All rights reserved. EYSENCKS TEORI Forsøk viser at introverte og ekstroverte ikke ligger på forskjellig hvilenivå Men: introverte er mer reaktive for moderate stimuleringsnivåer Eysenck reviderte sin teori • Forskjellen mellom introverte og ekstroverte ligger i aktiverbarhet, ikke i hvilenivå EYSENCK’S THEORY When given a choice, extraverts prefer higher levels of stimulation than introverts Geen (1984): Introverts and extraverts choose different levels of stimulation, but equivalent in arousal under chosen stimulation © 2008 The McGraw-Hill Companies, Inc. All rights reserved. EYSENCKS TEORI Når de får velge foretrekker ekstroverte høyere stimuleringsnivå enn introverte Geen (1984) • Introverte og ekstroverte velger forskjellig stimuleringsnivå • Ekvivalent aktivering under den valgte stimuleringen EYSENCKS TEORI: GEEN (1984) SENSITIVITY TO REWARD AND PUNISHMENT Personality based on two hypothesized brain systems Behavioral Activation System (BAS): Responsive to incentives (cues to reward) and regulates approach behavior © 2008 The McGraw-Hill Companies, Inc. All rights reserved. FØLSOMHET FOR BELØNNING OG STRAFF To systemer i hjernen Behavioral Activation System (BAS) • • • • • • Mottakelig for incentiver, tegn på belønning Regulerer tilnærmingsatferd Produserer impulsivitet Hemmer tilbaketrekning Øker aktivering jo nærmere målet personen kommer Lærer best ved belønning SENSITIVITY TO REWARD AND PUNISHMENT Behavioral Inhibition System (BIS): Responsive to cues to punishment, frustration, uncertainty, and motivates ceasing, inhibiting, or avoidance behavior Active BIS produces anxiety, active BAS produces impulsivity © 2008 The McGraw-Hill Companies, Inc. All rights reserved. FØLSOMHET FOR BELØNNING OG STRAFF Behavioral Inhibition System (BIS) • • • • • Mottakelig for tegn på straff og frustrasjon Regulerer tilbaketrekkingsatferd Produserer angst Hemmer tilnærming Lærer best ved straff Under separat nevral kontroll To ulike læringssystemer SENSITIVITY TO REWARD AND PUNISHMENT Integration with Eysenck’s model: Impulsive = high extraversion, moderate neuroticism; Anxious = moderate introversion, high neuroticism According to Gray, impulsive people do not learn well from punishment because of weak BIS; learn better from reward— supported by research © 2008 The McGraw-Hill Companies, Inc. All rights reserved. FØLSOMHET FOR BELØNNING OG STRAFF Integrasjon med Eysencks modell • Høy BAS/Impulsiv = høy ekstroversjon? • Høy BIS/Engstelig = høy nevrotisisme? SENSATION SEEKING Tendency to seek out thrilling, exciting activities, take risks, avoid boredom Early sensory deprivation research Hebb’s theory of optimal level of arousal © 2008 The McGraw-Hill Companies, Inc. All rights reserved. SENSATION SEEKING Tendens til å oppsøke spennende aktiviteter, ta risiko, unngå kjedsomhet Hebbs teori om optimalt aktiveringsnivå • Hvis underaktivert er aktivering belønnende • Hvis overaktivert er mindre aktivering belønnende • Vitalbalanse? SENSATION SEEKING Zuckerman: High sensation seekers are less tolerant of sensory deprivation; require much stimulation to get to optimal level of arousal Zuckerman’s Sensation Seeking Scale Moderate positive correlation between extraversion and sensation seeking © 2008 The McGraw-Hill Companies, Inc. All rights reserved. SENSATION SEEKING Zuckermans modell • Sensation seekers er mindre tolerante for sensorisk deprivasjon • Behøver mye stimulering for å oppnå et optimalt aktiveringsnivå • Moderat positiv korrelasjon mellom skårer på Zuckermans Sensation Seeking Scale og ekstroversjon • Høyere sensation seekers • Opprørspoliti, fallskjermhoppere, spillere SENSATION SEEKING Physiological basis for sensation seeking • Neurotransmitters—chemicals in nerve cells are responsible for the transmission of nerve impulse from one cell to another • Monoamine Oxidase (MAO)—enzyme that maintains a proper level of neurotransmitters © 2008 The McGraw-Hill Companies, Inc. All rights reserved. NEUROTRANSMITTERS AND PERSONALITY Dopamine—associated with pleasure Serotonin—associated with depression and other mood disorders Norepinepherine—associated with fight or flight response © 2008 The McGraw-Hill Companies, Inc. All rights reserved. NEVROTRANSMITTERE Dopamin • Assosiert med nytelse, glede, impulsivitet Serotonin • Assosiert med depresjon og stemningslidelser, lav impulsivitet Norepinefrin • Assosiert med fight/flight-responsen SENSATION SEEKING Physiological basis for sensation seeking • Too little MAO = too much neurotransmitter; too much MAO = too little neurotransmitter • High sensation seekers have low levels of MAO, producing a need for stimulation to reach the optimal level of arousal © 2008 The McGraw-Hill Companies, Inc. All rights reserved. SENSATION SEEKING Monoaminoxidase (MAO) • Enzym som regulerer signalstoffnivået i nervesynapsen ved nedbryting • For mye MAO = for lite signalstoff • For lite MAO = for mye signalstoff Høy sensation seeking relatert til lavt MAOnivå i blodet Lavere hemning og kontroll -> høyere impulsivitet • Ikke søking mot optimalt nivå NEUROTRANSMITTERS AND PERSONALITY Cloninger’s Tridimensional Personality Model • Novelty seeking—low levels of dopamine • Harm avoidance—low levels of serotonin • Reward dependence—low levels of norephinepherine © 2008 The McGraw-Hill Companies, Inc. All rights reserved. NEVROTRANSMITTERE Cloningers tredimensjonale personlighetsmodell • Søking etter noe nytt (novelty seeking): lavt dopaminnivå • Unngåelse av skade: lavt serotoninnivå • Avhengighet av belønning: lavt norepinefrinnivå Type 4 dopaminreseptorgenet (D4DR) • Visse kombinasjoner på genet knyttet til novelty seeking MORNINGNESS-EVENINGNESS Being a “morning-type” or “evening-type” of person is a stable characteristic Due to differences in underlying biological rhythms © 2008 The McGraw-Hill Companies, Inc. All rights reserved. MORNINGNESS-EVENINGNESS Many biological processes fluctuate around a 24-25 hour cycle—circadian rhythm; e.g., body temperature, endocrine secretion rates But wide individual differences are in the circadian rhythm, identified through temporal isolation studies © 2008 The McGraw-Hill Companies, Inc. All rights reserved. MORNINGNESS-EVENINGNESS Individuals with shorter circadian rhythms hit peak body temperature and alertness earlier in day, get sleepy earlier, than individuals with longer rhythm Individuals with shorter rhythm tend to be morning persons; individuals with longer rhythms tend to be evening persons © 2008 The McGraw-Hill Companies, Inc. All rights reserved. MORNINGNESS-EVENINGNESS Morningness-Eveningness Questionnaire Cross-cultural replication and documentation of stability of characteristic © 2008 The McGraw-Hill Companies, Inc. All rights reserved. BRAIN ASYMMETRY AND AFFECTIVE STYLE Left and right sides of the brain are specialized, with asymmetry in control of psychological functions Using EEG, can measure brain waves, such as alpha wave—an inverse indicator of brain activity © 2008 The McGraw-Hill Companies, Inc. All rights reserved. HJERNEASYMMETRI OG AFFEKTER Hjernens høyre og venstre deler er spesialiserte, kontrollerer forskjellige psykologiske funksjoner EEG: alfabølger • Jevne bølger på 8-12 Hz • Rolig, avslappet, uoppmerksom • Invers indikator på hjerneaktivering BRAIN ASYMMETRY AND AFFECTIVE STYLE Left frontal hemisphere is more active than the right when a person is experiencing pleasant emotions; right is more active than left with unpleasant emotions Patterns replicated in adults, children, and infants © 2008 The McGraw-Hill Companies, Inc. All rights reserved. HJERNEASYMMETRI OG AFFEKTER Ved positive affekter • Venstre frontale cortex mer aktiv Ved negative affekter • Høyre frontale cortex mer aktiv Samme mønster funnet hos voksne, barn, spebarn og aper BRAIN ASYMMETRY AND AFFECTIVE STYLE Research indicates that the tendency to exhibit asymmetry (favoring left over right, or right over left activation) is a stable individual characteristic Dispositionally positive persons show greater left frontal EEG activity; dispositionally negative persons show greater right frontal EEG activity © 2008 The McGraw-Hill Companies, Inc. All rights reserved. HJERNEASYMMETRI OG AFFEKTER Tendens til å vise asymmetri er en stabil individuell karakteristikk over tid Disposisjonelt positive personer (BASpreferanse) viser større venstresidig aktivitet Disposisjonelt negative personer (BISpreferanse) viser større høyresidig aktivitet BRAIN ASYMMETRY AND AFFECTIVE STYLE Conclusion: Person’s affective lifestyle may have origins in, or be predicted by a pattern of asymmetry in frontal brain activation © 2008 The McGraw-Hill Companies, Inc. All rights reserved. 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… © 2008 The McGraw-Hill Companies, Inc. All rights reserved. SUMMARY AND EVALUATION Use physiological measures as variables that may be correlated with personality traits View physiological events as providing causal substrate for personality trait © 2008 The McGraw-Hill Companies, Inc. All rights reserved.