PSYC 330 EXAM 1

notion that traits are categories of acts - trait categories like “dominance” and “impulsivity” have specific acts as members

• formulation of traits as purely descriptive summaries

make no assumptions about internality or causality, merely describes expressed behavior

(ex: the trait of jealousy accurately summarizes the general trend in george’s expressed behavior of  glaring at other men who talk to his girlfriend – but no assumptions are are about what cause george’s behavior)

individuals carry their desires, needs, and wants from one situation to the next; those desires and needs are assumed to be causal in the sense that they explain the behavior of the individuals who possess them

(i)    internal desire influences external behavior, causing people to act in certain ways

(ii)   traits can lie dormant in the sense that the capacities remain present even when particular behaviors are not actually expressed

(iii) when traits viewed as internal cues, other situational causes are ruled out (ex: joan parties a lot bc she’s extroverted, not bc her boyfriend drags her to them)

1. lexical

2. statistical

3. theoretical

all important individual differences have become encoded within the natural language- over time words were invented to talk about important differences

1. synonym frequency

2. cross-cultural universality

if an attribute has more than 1 or 2 trait adjectives to describe it, then it is a more important dimension of individual difference

if a trait is suf- ficiently important in all cultures that its members have codified terms to describe the trait, then the trait must be universally important in human affairs.

In contrast, if a trait term exists in only one or a few languages, then it may be of only local relevance.

(1)   Lexical approach initially focused on adjectives (ex: they’re friendly, shy,etc) - Only now the field is starting to focus more on other speech like adverb & other descriptive labels, to describe personality

(2)   Although helpful to know how the average is like, there might be traits or characteristics that researchers might be interested in, but aren’t captured well in vernacular (Ex: sensitivity to context) - Relying solely on lexicons might lead researchers to miss out on important aspects of personality research

“boil down” data to reveal underlying trait MVPs – good for crunching big data

Ex: factor analysis

(1)   Starting from whatever is given from raw data, then statistically running analyses to look for themes within the given data

(2)   Start with LOTS with individual items

(3)   Then identify groups of items that covary w/ one another but not w/ other items

(4)   Ex: not all 50 items on a survey are directly about conscientiousness, but look for items that clump together and may lead to conclusions about conscientiousness

(a)   Paragraph analogy – you’re reading newspaper article, then somehow the words on the paper all get scattered, in order to piece it back together you determine how the items connect to each other, narrow down which items connect with each other

(1)   It’s only as good what you put in – if the specific items are good, you’re able to capture good connections, whereas if the items are insufficient then you don’t get as good of an analysis

You start with a Theory that guides in identifying important variables, not how the data shakes out

(1)   Ex: elaboration likelihood model (petty & cacioppo, 1984) - Asked How much are ppl thinking?

“good” theory charts important traits clearly

(1)   How might the trait relate to each other and what might that predict?

(2)   Comprehensive

(3)  parsimony

the theory does a good job of explaining all of the facts and observations within its domain - explains more empirical findings

does the theory provide a guide to important new discoveries about personality that were not known before? Theories that steer scientists to making these discoveries are generally superior to theories that fail to provide this guidance.

does the theory provide precise predictions that can be tested empirically?

does the theory contain few premises and assumptions (parsimony) or many premises and assumptions (lack of parsimony)? As a general rule, theories that require many premises and assumptions to explain a given set of findings are judged to be poorer than theories that can explain the same findings with fewer premises and assumptions.

(1)   Lead to Difficulty in behavior predictions & connections

(2)   Not falsifiable

(3)   Inherently disconnected from daily life & experience – low generalizability

(4)   Lack of clarity could lead to inappropriate assumptions

(a)   Type 1 and type 2 error could occur at the same time

• hierarchical structure: 4-tiered, nested system (you can look down to the specific acts of personality & up to supertraits)

• biological underpinnings:

  • He asserted that there is a causal relationship between ppl’s behavior and physiological factors “important” traits should…

    • Be heritable

    • Have a psychophysiological foundation – physiological differences as the starting point of characteristic differences (There is more than what we can with our naked eyes behind behavior)

• Psychoticism (P)– when person is high in psychoticism, lack of empathy, lack of feelings of remorse, high impulsivity, sometimes cruelty, pleasure & stimulation seeking

  • aggressive, antisocial, cold, impersonal

• Extraversion-introversion (E) – enjoying and seeking sensations

  • sociably, lively, active, assertive

• Neuroticism-emotional stability (N) - proneness to experience negative emotions (depression, anxiety, etc)

  • anxious, depressed, shy, moody, emotional

Eysenck holds PEN

goal: identify & measure personality’s basic units

• cattell was a proponent of statistical approach - factor analysis

cattell identified 16 dimensions of personality including:

• warmth

• reasoning

• emotional stability

• dominance

• liveliness

• rule-consciousness

• social boldness

• sensitivity

• vigilance

• abstractedness

• privateness

• apprehension

• openness to change

• self-reliance

• perfectionism

• tension

Comprehensive model

(1)   Can get cumbersome, or have to sacrifice some items in analysis

(2)   16 factors not always replicable

(3)   Parsimony problem – are the 16 factors all distinguishable? Or can they collapse into common factors

wiggins interested in interpersonal traits (interpersonal - interactions among people involving exchanges) & the 2 resources that define social exchange are love and status

• dimensions of status and love define the 2 major axes of the wiggins circumplex

1. provides an explicit definition of interpersonal behavior (possible to locate any transaction in hich the resources of status or love are exchanged within a specific area of the circumplex pie)

2. specifies the relatinships b/t each trait and every other trait within the model

   1. adjacency - how close the traits are to each other in the circumplex (positively correlated)

   2. bipolarity - traits located at opposite sides of the circle & negatively correlated

   3. orthogonality - traits that are perpendicular to each other on the model, entirely unrelated (ex: dominance is orthogonal to agreeableness)

3. alerts investigators to gaps in investigations of interpersonal behavior

i)      Thought of as on a dimensional range (high to low)

ii)     Started in the lexical approach

OCEAN:

• Openness: novelty seeking (new experiences), openness to change (adaptability), openness to knowledge

  • if low, then not comfortable to change, new experiences, not high in adaptability

• conscientiousness: organized, detail-oriented, punctual, tidiness

  • on the extreme, perfectionism

  • someone low on conscientiousness more of a go-with-the-flow kind of person, not caring abt deadlines as much

• extraversion: sensation-seeking characteristics

• agreeableness: more important to get along than to go against standards, caring, nurturing

• neuroticism: anxiousness, overthinking, frequent mood changes (emotional instability/volatility)

  • someone who’s low on neuroticism varies less in emotions

the “big five” bc there’s replication across

• samples

• items formarts

• ages

• languages/formats

• “troublesome” 5th factor – openness out of the five factors, tougher to be replicated

• Conceptually, the definition of openness varies a lot

• Data gets messy bc of diff operational definitions

• McAdams &Walden (2010):

  • There is more to personality than just traits

  • The model doesn’t capture other dimensions of personality

  • “HEXACO can replace the big five”

• Atheoretical – M&W state that it might have been atheoretical before, but not so much in modern day

• Overreliance on factor analysis – M&W disagree bc there has been additional work to support the model’s construct validity (does it capture the elements of the concept it seems to talk about)

• *Omits important traits (like honesty) –*W&M agree but state that later works have incorporated other traits like honesty

• Antiquated view of trait measurement – W&M agree, but this criticism should be applied to the entire field of personality psychology

  • `Cumulative vs. differential (cumulative would say that more of a trait is positive but higher is not always better (differential)

• Can be trumped by a 2-factor system: W&M say that if Block thinks the big five misses out on traits, then it doesn’t make sense to leave out even more elements

M&W agree that the big five model is good for what it tries to do – good at describing traits BUT, there’s several levels of personality:

• ACTOR – dispositional traits (temperament), inferred from social behavior; emerges in birth & early childhood

• Observable traits & linked to the big five

• AGENT - clear and self-conscious comprehension of the self as purposive and goal-directed. Agents form goals, strivings, projects, plans, and the like for their own lives; emerges in late childhood & adolescence

• AUTHOR – person is their own meaning-making narrator, develops and internalizes an evolving, self-defining life story that explains how the person came to be and where their life may go in the future; emerges in early adulthood

• Considered a potential replacement of the five-factor model

• 6th factor: honesty-humility (on opposite side, arrogant, conceited, greedy, pompous)

• Ex:

  • “I would never accept a bribe, even if it were very large”

  • “I’d be tempted to use counterfeit money if I were sure I could get away with it” (R -reverse coded)

• Connections to “dark triad”

  • Narcissism, Machiavellianism (tendency to use others, to be manipulative and calculating), psychopathy

1. “meaningful individual differences exist”

2. “traits are relatively stable over time”

3. “there is some consistency to traits across situations”

• Humans differ from each other in important ways that impact aspects of their lives (goals, traits)

• Influences researchers’ ability to capture traits

• Statistics are important to trait researchers bc they can measure & compare, make predictions about individuals based on those stats

• Color wheel analogy – you can start from what feels like a small number of colors, but when you put them together, you can see a wider spectrum of colors

  • Diff amounts and combos of traits give rise to the vast variability when it comes to human outcomes

• (Initially in the field, researchers thought traits were stable over time, but now it is “relatively” bc there’s been empirical work that clarified that not everyone is the same throughout the entirety of their lifetime)

• BUT Behavioral manifestations may change

  • Relatively strong negative correlation between number of childhood tantrums & job longevity (r=-0.45)

  • There are behavioral expressions of the same underlying traits (the trait itself didn’t change, only how it’s expressed)

• Rank order differences:

  • To assess this, you can track traits over time(longitudinal studies), accounting for expected changes

    • Ex: we generally assume that kids are more impulsive than adults, if jimmy is more impulsive than Timmy when they’re young -→ we expect jimmy and Timmy to be less impulsive when they grow u -→ but rank order diff states that jimmy is likely more impulsive than Timmy even at an older age

• COVID pandemic has given people a chance to become more aware of their traits

  • Ex: ppl spend more of their time at home, they become more introverted bc they spend less time with others & also ppl became more aware that they like spending time with others in the vast amount of free time allowed towards the end of quarantine (so more extroverted)

• New research suggests that it has…

  • Decreases in Openness, conscientiousness, extraversion & agreeableness

  • Increases in neuroticism- Esp. pronounced among YOUNG ADULTS (college students)

  • “disrupted maturity” (sutin et. Al., 2022) (iv)

• Original assumption: Behavior=Person (behavior is a function of who you are as a person)

• Ex: if they display outgoing behavior, it must be because they’re extroverted

• Push-back on idea of consistency of traits across situations

• situanism= behavior due to context, not just behavior, if the behavior changes when the context changes

• Hartshone & may’s (1928): “honesty study”

  • Student who cheated in one class was a stellar student who never cheated in another class = according to context, people’s behavior changes

• Michel’s marshmallow test: behavior is shaped largely by the exigencies of a given situation and the notion that individuals act in consistent ways across different situations, reflecting the influence of underlying personality traits, is a myth

1. Demonstrate how situation changes behavior - Examine Delayed gratification, impulsivity

2. Mischel state that People can be flexible when there’s reframing of the situation (ex: if kids are told the marshmallow is fake, more likely to wait)

#3 tweak: person-situation interaction

&

#3 tweak: aggregation

B= f(P*S) ; behavior is a function of personality and situation

• Strong vs. weak situations

  • Strong situation = the situational constraints are so powerful they control the behavior (almost anyone would behave the same way under the same circumstances)

  • Weak situation = not a lot of pressure, leads to personal differences in behavior

interactions with situations include selection, evocation, and manipulation (which reflect our personalities)

• selection: we choose situations to enter (how we choose our friends, romantic partners, hobbie, classes, careers)

  • ex: someone who’s outgoing selects team-oriented activities

• evocation: the reactions we produce in other UNINTENTIONALLY (we create he social environment that we inhabit)

  • ex: someone who’s very talkative unconsciously makes the people around feel like they can’t talk

• manipulation: ways in which we INTENTIONALLY attempt to influence others

• ex: someone who knows that their friend is going through a tough time brings them flowers and candy to make them feel better

• More data= more accurate picture

• Jackson et al. (2015)

  • Predicting longevity from S-data vs. lots of O-data

  • Aggregated O-data (from friends)= better predictor of someone’s longevity than S-data

• Personality tests are better predictors of general tendencies rather than single acts

1. carelessness

2. faking

3. wording

people may not be completing the survey with quite the care and effort that you would expect them to

• Satisficing (Krosnick) – ppl may be using mental shortcuts or not putting effort into taking the test

• Ex: acquiescence, nay-saying (saying yes to every single question or no to every Q)

(1)   Short(er) surveys

(2)   Duplicate items (if same Q answered differently,then redflag)

(3)   Reverse-coding

(4)   Infrequency scale

*some of these prevent carelessness, some of them lets the researcher recognize the participants’ carelessness

• faking goodness – social desirability bias (making yourself seem better than in reality for social acceptance)

• faking bad – access to certain resources that you would not get if you didn’t meet the criteria (ex: faking injury as more severe to get it covered by insurance)

(1)   faking good/bad profiles (Cattell et al, 1970) - made fake profiles so they could compare with answers and see if they were similar

(2)   neutral wording (instead of saying “on a scale of 1-10, how depressed are you?” you ask “how often do you feel apathetic?”)

(3)   anonymity – if person is able to stay anonymous, no need to fake responses for their benefit

difficult wording of questions, ambiguous wording, assuming questions (asking how long ago someone got their license when they didn’t actually get their license), Qs that ask more than one Q, lead participants to be confused or not understand the question, which could lead to invalid responses

categories – opting for dichotomies can lead to misrepresentation/lack of inclusivity of people

• categorizing is a problem bc ppl in reality fall on a dimensional spectrum of conditions, and may not show the same symptoms/behavior as some others who have the same illness

if more is always better -→ examined dominance vs. ideal point models of personality measurement

• found that more is not always better and there are sweet spots to traits

cognitive bias that occurs when individuals believe that generic personality descriptions and statements apply to themselves.

In reality, the description is general and vague enough to apply to almost everyone.

ex: “omg not being able to commit to a single job is so me” but 10 other people agree

바, 너만 그런거 아니야 (barnum)

• Modern lie detector – polygraph – mechanical devise relies on psychophysiological measures like heart rate, respiration, skin conductance

• Use of physiological measures began in 1900s, w/ idea that it’s useful for detecting nervous arousal that often accompanies lying

• Originally designed to detect guilt reactions that arise from denying specific criminal acts, but employers used to screen general honesty

• During the 1970s-1980s, most people took a polygraph test as part of an employment screening procedure, often when applying for jobs in fast-food outlets

• However, lying is not always accompanied by physiological arousal and sometimes physiological arousal is not accompanied by lying -→ no “lie detection” test was foolproof

• In 1988, congress banned the use of polygraph in private sector

• Instead of polograph, companies use integrity tests that are designed to assess whether a person is generally honest, trustworthy, reliable, helpful and dependable

• Low test-retest reliability (Categorical treatment of continuous traits)

• Barnum effect – vague items/ statements

• Treats some traits as mutually exclusive (Ex: thinking “v” perceiving – you have to be either thinking OR perceiving (not a mix of both)

• High Face validity – easy to determine what trait is being determined (ppl can decide the way they want to present themselves, too obvious)

• Low Construct validity – does this thing actually measure what we think it measures? (The MBTI test doesn’t really correlate to a lot of stuff)

• Low predictive validity

• Minnesota multiphasic personality inventory (MMPI)

  • Identifying significant dysfunction

• California personality inventory (CPI)

  • Law enforcement suitability

• Hogan personality inventory (HPI)

  • Good psychometric properties – high reliability, high validity, good at predicting, has correlations to many things

  • Go-to for business settings

• Worries about misuse of BG findings

  • Holocaust

  • “the bell curve” – started by looking at intelligence differences across groups

  • Legal implications - If someone has a genetic propensity for violence, is a person responsible for the genes they inherited?

  • *Genetic determinism: belief that genetic contributions to phenotypes are exclusively or at least much more important than the contributions of other factors such as epigenetic and environmental ones, even in the case of complex traits such as behaviors and personality

• Remember: “is ≠ ought”

• Role of free will

genetic info

i)      Allele is a variation of a gene

physical, observed characteristics (physical expression of underlying genes)

• traits

many genes influence a trait (few, if any, are causal)

the GENOTYPE DRD4 – “novelty seeking gene” is associated with the PHENOTYPE of extraversion, impulsivity, quick-temperednedd, excitable, exploratory

• focused on gene structure & function

• more fine-grained

• starts with what gene is thought to be linked with that outcome

• candidate gene studies – searching for what one single gene does

  • “warrior gene” (MAOA)

• Starting at phenotypic level

• What “mix” of nature & nurture accounts for observed trait diffs?

• *nature-nurture debate exists only at group level, across diff groups= for individuals, there is inseparable intertwining of genes & environment

• Proportion of phenotypic variance across individuals that’s explained by genetic variance (Ex: height)

• Falconer’s formula: Heritability= 2 (minozygotic r – dizygotic r)

  • Monozygotic twins are genetically identical, dizygotic twins share fewer genes

  • ‘r’ is the correlation coefficient

  • How similar are identical twins compared to fraternal twins

• Can’t be applied to a single individual

• Is NOT constant across time/pops

• Heritability is an estimate – there are other factors that affect personality

artificial selection- as occurs when dogs are bred for certain qualities-can take place only if the desired characteristics are under the influence of heredity.

• selective breeding occurs by identifying the dogs that possess the desired characteristics and having them mate only with other dogs that also possess the characteristic

• manipualtion of behavioral and physical traits

• if heritability of the desired trait is high, then selective breeding will be highly successful and will happen rapidly

correlate the degree of genetic relatedness among family members with the degree of personality similarity.

• They capitalize on the fact that there are known degrees of genetic relatedness among family members.

• If a personality characteristic is highly heritable, then family members with greater genetic relatedness should be more similar to each other than are family members with less genetic relatedness.

• If a personality characteristic is not at all heritable, then even family members who are closely related \n genetically, such as siblings, should not be \n any more similar to each other than are family \n members who are less genetically related to \n each other.

• Identical twins raised apart

• A high number of similarities although raised in diff environments

1. MZ vs DZ twins

2. equal environments assumption (EEA)

3. adoption studies

4. twins reared apart

Are MZ more similar than DZ? (identical vs. fraternal twins?)

• If yes, then it’s evidence of heritability

• Higher tendency of genes to have affected traits bc identical twins share genes more than fraternal twins

• Something about the shared genetic makeup that contributes to similarity more than fraternal twins who only share 50% of their genetic makeup

twin method assumes that the environments experienced by identical twins are no more similar to each other than are the environments experienced by fraternal twins (“environments for MZ & DZ twins are equally similar”)

• If they are more similar, then the greater similarity of the identical twins could be due to the fact that they experience more similar environments rather than the fact that they have more genes in common.

• If identical twins are treated by their parents as more similar than fraternal twins are treated by their parents—for example, if the parents of identical twins dress them in more similar clothing than do the parents of fraternal twins—then the greater similarity of the identical twins might be due to more similar treatment.

• If parents dress their identical twins in the same way, compared to fraternal twins who were dresses differently -→ violation of the assumption

• research finding: however twins are labeled, the environments experienced by identical twins do not seem to be functionally more similar to each other than the environments experienced by fraternal twins.

• does child resemble adoptive or bio parents more

• nurture: when kids resemble their adoptive parents more than bio parents

• nature: when kids resemble their bio parents more than adoptive parents

they allow direct estimates of genetic effects on behavior and health, because they share all their genes, but differ in their environments.

Big Five (OCEAN) heritability estimates b/t 20% and 50%

• 20-50% of observed individ diffs = due to genetic diffs

• A, C, O: 20-45% (heritability lower than E & N)

• E & N 55-60% (we have a better foundation of these traits in physiology)

• Environmentality – percentage of observed behavior NOT due to genetics

• attitudes tend to be stable over time, sometimes linked with actual behavior

  • convervative values preferred over modern values, heritability of .59

• genes appear to influence occupational preferences -→ occupational preferneces like desire for competititon and wealth can lead to choosing occupations in which more status and income are actually achieved

• however, heritability nonexistent for belief in god, involvement in religious affairs, and racial integration

drinking & smoking seen as behavioral manifestations of personality dispositions, like sensation seeking, extraversion, and neuroticism

• Individual differences in drinking and smoking habits also show evidence of heritability. - identical twin who smoked was 16 times more likely than an identical twin who didn’t smoke to hve a twin who also smoked

• heritability tests for drinking more mixed, but show moderate heritability

  • but for alcoholism,shows stronger heritability -→ genetic link b/t alcoholism and conduct disorder (antisocial behavior)

• Shared: features shared by siblings (Ex: # of books in the home, vacations taken)

• Non-shared: features that diff across siblings; helps us identify differences in traits (Ex: peer group)

• Current research: non-shared environmental influences = critical for personality

Diff genotypes exposed to diff environments -→ we’re more likely to find the same genotypes in certain environments

ex: individuals with different genotypes (e.g., those with high versus low verbal abilities) are exposed to different environments (e.g., high versus low stimulation)

Correlation can be…

• Passive: individ didn’t do anything to be in that environment (passive genotype-environment correlation)

  • kid w/ good verbal skills lives in a house with lots of books bc parents like to read

• reactive: related to evocation, eliciting responses without intention (reactive genotype-environment correlation)

  • kid who loves to be touched “trains” parents to hold her

• active: related to selection, individ chose to be in that environment (active genotype-environment correlation)

  • thrill-seeker chooses to take up sky-diving

diff genotypes in same environment lead to diff responses

• ex: introverts vs. extroverts perform differently in equally loud setting

MAOA-L: monoamine oxidase A

• Lower levels of MAO (enzyme)-→ higher levels of circulating neurotransmitters -→ linked to less inhibition, higher levels of impulsivity, violence, aggression

• inhibits the brake system in brain

Role of environment:

• Upbringing: People who had lower activity MAOA and had committed multiple violent crimes found to have had difficult childhood environment

• Social support -→ less social support, lower MAOA-L activity

aim: To investigate whether the MAOA gene predicts behavioral aggression after provocation

Participants of McDermott et al:

-78 male subjects in 2 different groups \n -Some carrying MAOA-H (high) \n -Some carrying MAOA-L (low)

Procedure of McDermott et al:

~~-~~Subjects could administer unpleasantly hot (spicy) sauce to an opponent who doesn't like the taste \n -How much hot sauce administered was the behavioral measure of aggression

Procedure 2

-In each round subjects had a portion of their earnings (experimentally manipulated) taken from a vocabulary task from an anonymous, fictional person \n -Participants could punish the player through forced administration of hot sauce

Procedure 3

Participants were told they were given a new supply of hot sauce each time which they could forcefully administer or trade in for money

What were the levels of amount taken?

80% and 20% \n High take is 80% \n Low take is 20%

-Researchers found evidence of a gene-environment interaction

- having more taken made them angrier regardless of gene \n -but Individuals with low MAOA (neurotransmitter build-up) were more likely to administer hot sauce to their opponent when 80% of their earnings were taken more than those with high MAOA \n -Lower differences between MAOA groups when only 20% of the money was taken

= “warriors” with low MAOA react more aggressively under conditions of high provocation

1. electrodermal activity (EDA)

2. cardiovascular activity (Blood pressures & heart rate)

3. brain activity (EEG & fMRI)

4. saliva testing

5. blood testing

tests sweat gland permeability on palms of hands or soles of feet, observed as changes in the resistance of the skin to a small electrical current -→ the more water present in the skin, the more easily the skin carries/conducts electricity

• SNS (sympathetic nervous system) arousal -→ prepares body for fight-or-flight mechanism during episodes of anxiety, startle, or anger

• BP(blood pressure)-activation of the SNS in fight-or-flight response

• HR (heart rate) – anxiety, arousal, cognitive effort

measures electrical activity in the brain using small, metal discs (electrodes) attached to the scalp - obtained while person is asleep, is relaxed but awake, or is doing task -→ provides info about patterns of activation in various parts of the brain, which may be associated with diff types of medical conditions or cognitive tasks

images show which portions of the brain are active while the person is performing a specific task

• hormone levels (testosterone, oxytocin, cortisol)

• indicator of how competently a person’s immune system is functioning -→ quality of immune system goes up and down w/ stress or emotions and thereby may relate to personality

MAOA levels

1. extraversion-introversion (eysenck)

2. reinforcement sensitivity theory (RST)

3. sensation seeking

4. neurotransmitters & personality

5. morningness-eveningness

6. brain asymmetry & affective style

extraversion/introversion is more than just a social difference and is indicative of underlying physio diffs

Eysenck’s original theory:

• introverts= higher baseline levels of cortical activity in ARAS (brain stem structure associated with arousal)

• BUT… EEG findings stated that there was no diff @ rest = in the absence/low level of stimulation, arousal levels were comparable b/t introverts and extroverts

Eysenck’s revised theory:

• Diff b/t introverts & extroverts = arousability

  • Introverts = more reactive to stimulation

  • Extroverts = “stimulation hungry”

• Ppl have diff sweet spots for arousal that they operate best under

• “IV1”: EPI(Eysenck personality inventory) score (extravert, introvert) – ppl come into take a personality survey, if above a certain number then extrovert, if not then introvert

• Participants have to perform a task while there’s noise in the room

• IV2: 3 noise conditions

  • Choice- 1/3 of participants can choose the level of noise they want to work under

  • assigned same – if extrovert, you don’t get to choose but researchers choose the level of noise other extroverts chose, same for introverts

  • assigned other – if introvert, then receives noise level that the last extrovert chose (same for extrovert- introvert choose for them)

• DV1: measured “physio arousal” (HR, EDA)

• DV2: learning task performance

personality main effects:

1. Introverts selected quieter noise levels (M=55dB) than extroverts (M=72dB)

2. Introverts = more physio arousal than extroverts (HR of introverts significantly higher than that of extroverts)

interactive effect on learning:

1. High bars = bad performance

2. When both introverts and extroverts under choice condition, they set it at their optimal level and they perform equally well

3. When assigned the same noise condition, when in the noise environment of the same genotype, performance is still relatively high for both introverts and extroverts

4. In the assigned other condition, both extroverts and introverts do not perform well, but introverts perform much worse than extroverts when not in their optimal environment a. Extroverts are understimulated if they’re in introverts’ desired noise level b. Introverts are overstimulated when they're in extroverts’ desire noise level

Geen’s findings fit w/ Eysenck’s revised model bc diffs emerge in reaction to stimulation -→ introverts and extroverts have different sweet spots for arousal

Jeffrey created model of human personality based on 2 hypotheiszed biological systems in the brain:

1. behavioral activation system (BAS)

2. behavioral inhibition system (BIS)

responsive to incentives, such as cues for reward, and regulates approach behavior, most likely through the dopamine system

ex: a child learns about an ice cream truck that makes deliveries to their neighborhood while playing music -→ when child hears music (cue of reward), their BAS creates the urge to run out into the street to find the truck (approach motivation)

• associated with impulsivity, desire to engage in new stuff (high Extroversion, moderate Neuroticism)

accelerator that motivated approach behavior

responsive to cues for punishment, frustration, and uncertainty. The effect of BIS activation is to cease or inhibit behavior or to bring about avoidance behavior.

ex: child scolded by mother for running into the street, street becomes a punishment cue to the BIS, which causes the child to inhibit their behavior

• associated with anxiety (high neuroticism, lower extraversion)

brake that inhibits behavior/help stop person what they’re doing

• Connections to other domains

• Neural underpinnings for individual diffs in:

  • Coping/adjustment

  • Anxiety/fearfulness due to sensitive BIS

  • Motivation

    • Processing of threats vs. incentives

    • Sensitive BIS

  • Learning:

    • Ex: impulsive folks learn better via sensitive BAS

sensation seeking: Tendency to seek out excitement, take risk, avoid boredom

Hebb (1950s):

• Sensory deprivation studies – at some point, ppl tapped out of the study (to be completely devoid of sensations was aversive)

  • Some ppl went longer, some ppl were not as bothered-→ there are individual diffs in the optimal level of arousal (some amount of stimulation that is actually desirable for a person, we are motivated to seek that out)

  • this was controversial at the time bc it was radical that ppl voluntarily seek out sensation

• believed that people least tolerant of sensory deprivation were in high need of sensation

• developed sensation-seeking scale (questionnaire designed to measure the extent to which a person needs novel/exciting experiences &enjoys thrills/excitements)

  • predicted how well ppl tolerated the sensory deprivation sessions

• moderately strong positive correlation b/t extraversion and sensation seeking

• thus, there is a physiological basis for sensation-seeking behavior -→ role of neuroTs

• MAO responsible for maintaining proper levels of neuroTs -→ high sensation seekers tend to have low levels of MAO in bloodstream -→ sensation seeking is caused by/maintained by having high levels of neuroTs in nervous system

1. dopamine

2. serotonin

3. norepinephrine

pos association w/ pleasure & pleasure-seeking behavior

neg association w/ depression, irritability

activates “fight or flight” response