Psychological - Eysenck personality

• Extraversion

  Positive, Outgoing, needing external stimulation

  Biological basis - under-aroused nervous system

  Leads to risk taking
• Neuroticism

  Depressed and anxious

  Biological basis - Volatile nervous system

  Leads to unpredictability
• Psychoticism

  Aggression and Unpredictability

  Biological basis - High testosterone

  Leads to aggression and lack of empathy
• EPI/EPQ


  The measurement of criminality
• Socialisation 


  Socialisation impacts development - building of attachments in early childhood and seeing, speaking and considering others

  • Criminals did not learn to consider others and delay gratification
  • So both nature and nurture are important
  • Those high in extraversion and neuroticism had nervous systems that were harder to condition
• Evidence supporting the criminal personality theory

  Eysenck and Eysenck (1970) - Strength

  Compared 2070 male and prisoners’ scores on the EPI with 2422 male controls

  Groups were subdivided into age groups, ranging from 16-69

  On measure of Psychoticism, Extraversion, and Neuroticism prisoners recorded higher scores than controls which accords with predictions of the theory
• Evidence supporting the criminal personality theory

  Farrington et al (1982)

  Reviewed several studies and reported that offenders tended to score higher on Psychoticism measures but not for Extraversion and Neuroticism

  There is also very little evidence of consistent differences in EEG measures (used to measure cortical arousal) between extroverts and introverts, which casts doubt on Eysenck‘s theory
• Oversimplification - Weakness 


  The idea that all offending behaviour can be explained by a single personality type has been heavily criticised

  Moffitt (1993) - proposed several distinct types of adult male offender based on the timing of the first offence, and how long offending persists
• Oversimplification - Weakness

  Eysenck’s criminal type is out-of-step with modern personality theories

  John Digman (1990) - five factor model of personality suggests that alongside extraversion and neuroticism, there are additional dimensions of openess, agreeableness and conscientiousness

  Multiple combinations are available and therefore a high extraversion and neuroticism does not mean offending is inevitable
• Culture bias - weakness

  Bartol and Holanchock (1979)

  Hispanic and African-American offenders in a max security prison were divided into six groups based on their criminal history and the nature of their offence

  It was found that all 6 groups were found to be less extroverted than a non-criminal control group

  This suggested that this was because their sample was a very different cultural group than that investigated by Eysenck, which questions the generalisability of the criminal personality