Personality Theory.

• Because of this trait theories are sometimes called psychometric trait theories

• [3.3] the basic questions are: how many traits? How do we identify them? How are they related? What are their origins?

• [3.4] it is possible to find a relatively small number of traits that have important effects in a wide variety of contexts.

• So it is possible to construct theories that are simple and powerful

• How do we identify traits?

• Focus on self descriptions or other descriptions (parents, siblings, peers, friends, peers, etc.)

• Adjectives (“submissive”) versus behaviours (“It is hard for me to be assertive with other people”)

• Key question: Do these methods converge?

How are traits related?

• Two basic models:

• #1        Independent dimensions (‘orthogonal’)

• #2        Related dimensions (‘correlated’)        

• A special form of relatedness is ‘circumflex’ or ‘circular’ models

• Usually called ‘interpersonal’ models

• May want to distinguish different theories depending upon:

• Different methods of identifying traits (See slide 11)

• Different models of the relationships between traits (slides 12-17)

• Whether theories are idiographic or nomothetic

• Idiographic (‘one’s own’) versus nomothetic (‘lawful’) traits [‘personal’ language versus common language]

• Different levels of explanation:

• Descriptive versus explanatory (Neuropsychic, psychodynamic, interpersonal)

• May want to distinguish different theories depending upon:

• Different methods of identifying traits (See slide 11)

• Different models of the relationships between traits (slides 12-17)

• Whether theories are idiographic or nomothetic

• Idiographic (‘one’s own’) versus nomothetic (‘lawful’) traits [‘personal’ language versus common language]

• Different levels of explanation:

• Descriptive versus explanatory (Neuropsychic, psychodynamic, interpersonal)

• Pioneered the attempt to find quantitative methods to describe personal dispositions

• Letters to Jenny

• Emphasised that child and adult personalities were different in kind

• Qualitative differences rather than just quantitative differences

• The only trait theory to see personality as ‘open’ and therefore in a process of ‘becoming’ (‘propriate striving’)

• Insisted that traits had neuropsychic causes, but little more than speculation about the nature of those causes

[6] Interpersonal Circles and Five Factor Models

• Historical Introduction:

• Allport & Odbert (1936)

• Approx. 18000 trait names in Webster’s Dictionary

• That capture those dimensions that are theoretically important, because they are biologically or socially relevant

• Reduced to 16 variables by R. Cattell (1943-47)

• Using statistical analysis combined with some extra-statistical and ‘arbitrary’ decisions

• Subsequently:

• Interpersonal Circumplex (Leary, 1957) and Five Factor Models [FFM]

• The Five Factor Model

• McCrae & Costa

• OCEAN = Openness, Conscientiousness, Extraversion, Agreeableness, Neuroticism

• Why Five Factors?

• Five basic questions (Hampson, 1982)

• Q1: Will P dominate me ?  [E-I][Dom-Sub]

• Q2: Will I like P [Affiliation]

• Q3: May I trust P to do a good job? [Conscientiousness]

• Q4: Is P emotionally stable? [Neuroticism]

• Q5: Is P smart [Open-minded?  Open to culture?]

• Hence OCEAN

• Because of convergence between the Interpersonal and Five Factor Models the OCEAN dimensions are often described as the Big Five

[6] Interpersonal Circles and Five Factor Models

• Descriptive claims:

• As far as the lexicon is concerned, the factors can be identified in a very wide variety of languages (linguistic universals?)

• Stable over long periods of time [40-50 yrs]

• Explanatory claims [McCrae, Costa, and associates].  Link to neurological systems dealing with:

• behavioural activation versus behavioural inhibition [BAS, BIS][Gray]

• Positive affect versus negative affect [PANAS][Tellegen]

• Strengths:

• Optimal trade-off between goals of accuracy and parsimony (using the minimum number of dimensions)

• Broadly based measures of personality that are reliable and valid

• Models continue to develop

• Measurement scales are in the public domain

• Weaknesses:

• The structure of the trait lexicon may not be the same as the deep structure of personality

• The efficient measurement of common traits is not all that is needed for a theory of personality

• Is personality theory the psychology of a stranger? (McAdams, 1992)

R

• #1        Start with observation:

• Some clinical patients are very extraverted [hysterical, psychopathic], some very introverted [dysthymic disorders: anxiety, phobias, obsessive-compulsive]

• Clinical patients are unstable (by definition), normal subjects are stable (by definition), although there is a continuum between the two

• Suggested importance of dimensions E-I, N-S

• #2        Develop self-report scales to measure  E-I and N-S, validated against scores of criterion groups

• #3        Use scales to collect data about the effects of E-I and N-S in a wide variety of contexts

• #4        Use data to make inferences about the nature of E-I and N-S at levels of surface traits and source traits

• First theory:

• S-R theory based on the work of C.L. Hull: learning occurs when actions lead to the reduction of primary or secondary drives

• E have stronger reactive inhibition than I, so less likely to persist at a given task

• N have higher levels of drive than S, so more likely to have extreme reactions

• Led to work of behaviour therapy [largely productive] and to work on the ψ of crime (E+N → criminality?) and social attitudes (E = tough-minded, I = tender-minded)[largely unproductive]

• Replicated [primary] data:

• Speed and accuracy in motor skill tasks such as spiral maze

• Vigilance tasks: E worse than I, but time of day effects [interaction more important?]

• Learning ‘styles’: E want noisy, sociable environments

• Sensory thresholds: E higher thresholds for pain than I

• Perceptual after effects: shorter for E than I

• Secondary (more controversial) data

• Criminology and conditioning [E+N→…]        [X]

• Political attitudes

• E= tough-minded, I=tender-minded

• Fascists and communist both tough-minded and extravert, Liberals tender-minded and introverted                [X]

• Smoking and Health

• Protected if P+I+N                                [?]

• Personality and the paranormal        

• E more likely to have paranormal abilities because they are under-aroused: so less cognitive controls?                [?]

• Recent extensions:

• #1        Development of P dimension

• Supposed to measure tendencies to psychosis just as N measures tendencies to neurosis

• But more like tendencies to psychopathy?

• Eysenck now sees impulsivity as part of P rather than as part of E

• Generally thought to be a mistake        

• But more like tendencies to psychopathy?

• Recent extensions: [Health warning: put simply]

• #2        Rejection of initial biological theories ?

• Either:

• Many arousal systems: so only part of the story

• Or:

• E-I not related to arousal systems at all, N-S not related to visceral brain activity

• Best source: Eysenck, M. (1998) Personality: An Integrated Approach.

• Recent extensions:

• #3        Into cognitive neuroscience and genetics

• E-I linked to sensitivity in base levels of dopamine

• levels of dopamine linked to variation in gene D4DR

• N-S linked to levels of serotonin 

• levels of serotonin affected by variations in DNA

• P linked to research on endocrine system

• androgens lower arousal levels and remove inhibitions

• These claims are controversial

Evaluation

• Strengths

• Combines experimental psychology with the study of individual differences [important]

• Has generated an enormous amount of research, in the UK and abroad, in many domains

• Everyone agrees that E-I and N-S are basic dimensions that cannot be ignored

• Primary data set highly replicable

• Continue to examine links with neuroscience

• Progress is being made, despite considerable changes in thinking

Evaluation

• Weaknesses

• Many predictions from the theory rely on ad hoc assumptions

• Links between E and arousal often speculative and post-hoc

• Although progress continues to be made?

• Many parts of the theory [the early parts, and the most social parts] have failed

[8] General evaluation of trait theories

• Strengths

• The theories are empirical, testable, and tested

• Trait theorists have provided a technology for scientific research, linking studies of individual differences to general psychology

• Descriptive work has led to explanatory theories

• Trait theories cover many different explanatory theories [London & Exner, 1978]

• Weaknesses

• Are general traits an illusion [Mischel, 1963]

• Persons x situations debate Showing that trait  theorists need to pay more attention to personality in its social context [Eysenck, 1988; Magnusson & Törestad, 1993]

• Trait theory only part of the story [broadly-based pitched at level of ψ of stranger: see McAdams, 1992]