4 - Eysenck's Biologically Based Factor Theory

essence of Eysenck’s theory

uniting biology and trait theory

temperament

biologically based tendency to behave in particular ways from early life

heritability

extent to which a characteristic is influenced by genetics

meaningless

Esyenck thought factor analysis was _______ unless it could be connected to biology

criteria for identifying factors

1. psychometric evidence
2. heritability
3. theoretical sense
4. social relevance

psychometric evidence

(criteria for factors)

have to do factor analysis and find it across measurements with reliable results

heritability

(criteria for factors)

fit genetic models

* entirely eliminates learned aspects

theoretical sense

(criteria for factors)

start with a theory of what factor is, and then test it

* deductive approach

social relevance

(criteria for factors)

* cant just be hypothetical
* has to be connected to real world phenomenon

hierarchy of behaviour organization

1. specific acts or cognitions
2. habitual acts or cognitions
3. traits
4. types

specific behaviours

first stage of behaviour organization hierarchy

* discrete individual behaviours, may not be characteristic of that person
* \

habitual acts

second stage of behaviour organization hierarchy

* responses that have to reoccur under specific conditions
* creates reliability
* \

trait

third stage of behaviour organization hierarchy

* related habitual responses
* need to be extrapolated on basis of a system, factor analysis
* defined in terms of significant intercorrelations between different habitual behaviours
* Cattell’s source traits
* \

types

fourth stage of behaviour organization hierarchy

* superfactors, supertraits
* ex., introversion

extraversion

characterized behaviourally by sociability and impulsiveness and physiologically by a low level of cortical arousal

* optimism
* react less to sensory stimulation, thus can put selves in more stimulating events

introversion

characterized by unsociability and caution and by a high level of cortical arousal

* pessimism
* react more to sensory stimulation

Lemon drop study

found that introverts have greater sensitivity to stimuli in general, lower pain threshold

* a lot of salivation to lemon drops on tongue

neuroticism

higher scores indicate anxiety, hysteria, obsessive-compulsive disorders, or criminality

* overreact emotionally
* headaches, backaches


* low scores indicate emotional stability
* over responsive limbic system

\

diathesis stress-model

some individuals more vulnerable to illness due to genetic predisposition triggered by stress

* higher development of neurosis or psychoticism

introvert with high neuroticism

presents with depression

extrovert with high neuroticism

presents with somatic symptoms and outward emotional instability

psychoticism

higher scores indicate hostility, self-centeredness, suspicion, and nonconformity

* aggressive, psychopathic, antisocial


* low scores indicate proper superego function
* altruistic, socialized, empathetic, caring, conforming
* independent from other factors

Eysenck’s four personality inventories

* Maudsley Personality Inventory (MPI)
* only assessed E and N
* intercorrelation between factors
* Eysenck Personality Inventory (EPI)
* only E and N
* independent scales
* added faking detection
* Junior EPI
* developed by his wife
* Eysenck Personality Questionnaire (EPQ)
* added P

evidence for biological basis of personality

1. researchers found same factors across cultures
2. individual scores were stable over time
3. twin studies showed higher concordance for identical twins

\

antecedents (biological bases of perosnality)

* distal
* proximal

genetic and biological factors

* distal: DNA
* proximal: limbic system arousal

consequences (biological bases of perosnality)

* proximal
* distal

how the psychometric traits combine to different results

* proximal: conditioning, sensitivity, perception, memory, etc.
* distal: how it appears in the world
* sociability, criminality, creativity, psychopathology, sexual behaviour, etc.

extraverted and introverted children and learning

* extraverted children do better with active discovery learning
* introverted children do better with passive reception learning

biological basis of extraversion

introverts are more reactive than extraverts

* Beauducel predicted extraverts less cortically aroused, show worse performance in boring and monotonous tasks
* Dobbs found extraverts performed better than introverts on noise and music conditions, but not silent conditions

biological basis of neuroticism

neuroticism resulted from increased activity or responsiveness and lower activation thresholds in limbic system

* increased left amygdala activity
* reduced neural connections between amygdala and other regions controlling thoughts
* inhibits “off-switch” of amygdala, resulting in overactivity
* higher degrees of grey brain matter for high N
* high N more sensitive to negative emotional experience
* low N suppress emotions, lung cancer

Eysenck controversy

* he believed race impacted IQ
* contributed to discriminatory school practices
* studies not easily replicated
* cooking his numbers

critique of this theory

* biological evidence inconsistent
* falsified studies, difficult to replicate
* tried to essentialize trait theories are purely biological