Eysenck and Gray's Theories of Personality

Eysenck, Gray and the Big Three

Hans Jürgen Eysenck (1916 - 1997)

  • Background:

    • Comes from a German Jewish family.

    • Parents were actors; Eysenck was more science-oriented.

    • Left Germany in 1934 to escape from the Nazis.

    • Earned his doctoral degree in 1940.

    • Worked as a clinical psychologist.

  • Theoretical Contributions:

    • Developed his personality approach based on theoretical foundations using the types of Galen-Hippocrates and Jung.

Eysenck’s Basic Principles

  • Personality Factors:

    • Establish based on psychometric evidence.

  • Biological Background:

    • Heredity is crucial.

  • Theoretical Background:

    • Must be clarified before measurements on personality (contrasted with Cattell and factor analysis).

  • Social Relevance:

    • Factors must have social relevance.

Galen's Temperament Types

  • Continuum of Temperaments:

    • Galen stated that there are no complex temperaments (e.g., sanguine-choleric).

    • Eysenck argued that individuals can occupy any position between the two extremes of a continuum; personality traits are continuous variables.

    • Empirical findings suggest most individuals fall into the middle zone of this continuum.

Eysenck’s Fundamental Traits

  • Description of human behavior involves a few fundamental traits:

    • Extraversion/Introversion:

    • Lability/Stability:

    • Referred to as neuroticism (emotionality).

    • Psychoticism:

    • Initially considered a measure of intelligence, later developed into psychoticism.

  • Personality Types:

    • Determined by combinations of the two axes:

    • Instable Introverted = melancholic

    • Instable Extraverted = choleric

    • Stable Introverted = phlegmatic

    • Stable Extraverted = sanguine

Orthogonal Rotation of Personality Factors

  • High Neuroticism Traits:

    • Moody, anxious, rigid, sober, pessimistic, reserved, unsociable, quiet.

  • Introversion Characteristics:

    • Passive, careful, thoughtful, peaceful, melancholic, phlegmatic.

  • Choleric Traits:

    • Touchy, restless, aggressive.

  • Extraversion Traits:

    • Excitable, changeable, impulsive, optimistic, active, sociable, outgoing, talkative, responsive, easygoing, lively, and controlled.

  • Low Neuroticism Traits:

    • Reliable, even-tempered, calm, carefree, and indicate leadership qualities.

Types and Levels of Personality Traits

  • Type Level Traits:

    • Sociability (Extraversion):

    • Engaging strangers, smiling at people.

    • Impulsivity:

    • Making rapid decisions, telling jokes, buying a new car.

  • Specific Response Level:

    • Persistence (Introversion):

    • Social shyness, keeping at school work, completing jobs.

    • Studies alone; declines invitations; works on hobbies alone.

Eysenck’s Theory on Super Factors

  • Personality can be described along three dimensions:

    • Factor E: Extraversion/Introversion

    • Factor N: Neuroticism/Emotional stability

    • Factor P: Psychoticism/Superego function

Extraversion and its Characteristics

  • Biological Determination:

    • Differences are biologically and genetically determined.

  • Cortical Arousal:

    • High extraversion related to lower levels of cortical arousal; characterized by sociability, liveliness, quick wit, optimism, and impulsiveness.

    • Introverted traits include being quiet, passive, careful, thoughtful, and introspective; greater cortical arousal results in avoidance of excitement and careful planning.

Neuroticism/Emotional Stability

  • Describes an individual's excitability and emotionality.

    • High Neuroticism:

    • Requires less stress to trigger a neurotic disorder, prone to emotional overreactions and difficulties in emotional recovery.

    • Low Neuroticism:

    • Greater resistance to neurotic disorders even under extreme stress conditions.

Psychoticism

  • Defined as a rough personality trait added later by Eysenck.

  • Theoretical Assumptions:

    • Normality and psychological disorders exist on the same continuum.

    • Psychosis and neurosis are independent dimensions.

  • High P Scores:

    • Characterized by egocentrism, coldness, nonconformity, impulsivity, hostility, aggressiveness, suspicion, psychopathy, and antisocial behavior.

  • Low P Scores:

    • Altruistic, highly socialized, empathetic, caring, cooperative, and conventional.

Gray's Concept of Behavior

  • Contrasting Theories:

    • Neuropsychologist Gray (1981, 1987) contrasts with Eysenck regarding brain activity and behavior.

  • Brain Systems:

    • Proposed at least two independent neurobiological systems governing behavior:

    • Go (BAS):

      • Behavioral approach system focused on reward-seeking and positive emotions.

    • Stop (BIS):

      • Behavioral inhibition system focused on avoidance and negative emotions.

BAS and BIS Dynamics

  • BAS (Behavioral Activation System):

    • Responsible for approaching rewards; leads to umpositive emotions like hope and excitement.

  • BIS (Behavioral Inhibition System):

    • Reactive to punishment cues; extends its influence to various negative emotional responses and anxiety.

Comparison of Eysenck's and Gray's Theories

  • Independent Processes:

    • Gray asserts that anxiety and impulsivity arise from separate mechanisms linked to sensitivity to anxiety-inducing stimuli (BIS) and attraction to anticipated reward (BAS).

  • Extraversion and Neuroticism:

    • Gray views these as derived from anxiety and impulsivity rather than fundamental traits.

Psychological Disorders According to Gray

  • Anxiety Disorders:

    • Not combinations of introversion and neuroticism, but stem from BIS sensitivity (high anxiety tendency).

  • Psychopathy and Antisocial Traits:

    • Do not arise from a blend of extraversion and neuroticism but rather from an active BIS with low inhibition.

Neural Mechanisms Influencing Introversion

  • Beyond ARAS System:

    • Introversion determined by various neural areas:

    • Medial Septal area (attention control, complex processing).

    • Hippocampus (memory).

    • Orbitofrontal cortex (organization of social behavior).

    • These areas create a negative feedback loop influencing the level of introversion.

Measuring BIS/BAS

  • BAS Measurements:

    • Higher BAS tied to greater relative left prefrontal activity (EEG).

  • BIS Measurements:

    • Higher BIS linked to greater relative right prefrontal activity (EEG).

  • Self-reporting Questionnaires:

    • Developed by Carver and White, 1994, assess happiness, performance (BAS), and emotional responses (BIS).

  • Variance of Questionnaire Results:

    • 25% of variance can be explained by the asymmetry of brain activity.