Eysenck's personality theory

• What were the three personality types?

  Extroversion

  Introversion

  Neuroticism
• People's personality varies along two dimensions:

  Extraversion vs Introversion(E): how much stimulation is needed

  Neuroticism vs emotional stability(N): how emotionally unstable they are.
• Eysenck suggest that E and N measure characteristics of the nervous system.

  E measures your central and autonomic arousal level: the LOWER this is the more stimulation you need from your environment and the harder you are to condition successfully.

  N measures how strongly your nervous system reacts to aversive stimuli: The stronger your responses the more extreme your emotional changes. High N scorers are also hard to condition.
• Lower E levels : hard to condition

  Higher N levels: hard to condition
• People with High E scores are sociable, active, lively and sensation seeking. E is determined by the overall level of arousal in the persons CNS (central nervous system) and ANS (autonomic nervous system). High E scorers have a low level of arousal and therefore need more stimulation from their environment.
• People with High N scores are anxious, depressed, and react very strongly to aversive stimuli. N is determined by the overall level of lability in the person's CNS. Where N is low, the person has a stable, relatively un-reactive nervous system whereas a high N score results in a high degree of instability.
• People with a High P (psychoticism) score are aggressive, anti-social, cold and egocentric. He also believed P to be largely genetically determined as High P levels can overlap with serious psychiatric illnesses such as schizophrenia
• How does this link to criminality?

  Eysneck believes that whilst most people have personalities somewhere around the middle of both scales, the criminal personality scores high on both E and N.

  In other words, criminals tend to be strongly extraverted and neurotic
• What is conditioning?

  Where some psychologists argue that through experience, we learn to seek pleasure (or rewards) and avoid pain (or punishment).
• What is genetic inheritance?

  Esyneck argues that we learn through conditioning, but that some individuals inherit a nervous system that causes them to develop a criminal personality.
• Esyneck believes that extroverts have a nervous system that requires high levels of stimulation which leads to impulsive behaviour (which leads to punishment) and Neurotics are harder to condition into following societies rules. Therefore the combination of high E and N is likely to lead to criminality.
• What are the strengths of Eysneck's personality theory?

  -It describes how some measurable tendencies may lead to criminality

  -Studies suggest that offenders tend to have high E, P and N scores
• What are the weaknesses of Eysenck's personality theory?

  -Studies show that prisoners are not often extroverted

  -E measures two separate things (impulsiveness and sociability. These things don't always correspond.

  -Personality type and criminality are correlated, but this doesn't prove personality types cause criminality.

  -Convicted offenders may not be typical offenders

  -Eysneck used self-report questionnaires- people may lie, making the results invalid (social desirability bias)