Eysenck's Theory of the Criminal Personality (AQA A-Level Psychology): Revision Notes
Eysenck's Theory of the Criminal Personality
The theory
Eysenck developed his personality theory in 1963 as a general framework that later became influential in explaining criminal behaviour. The theory suggests that personality consists of measurable traits that exist on continuums, and the combination of these traits can predict criminal tendencies.
Initially, Eysenck proposed two core personality dimensions, but in 1976 he expanded the model to include a third trait after working with individuals with schizophrenia. The three personality traits are: extraversion, neuroticism, and psychoticism.
Eysenck's approach was revolutionary because it attempted to quantify personality traits rather than simply describing them qualitatively. This measurable approach allowed for scientific testing of his theories about criminal behaviour.
Extraversion
Individuals high in extraversion tend to be sociable, impulsive, expressive and enjoy risk-taking activities. Those low in extraversion (introverts) prefer their own company, act more cautiously, and are generally happier in solitary situations.
Neuroticism
People scoring high on neuroticism display behaviours such as nervousness, anxiety and obsessiveness. At the opposite end of this continuum, individuals are described as emotionally stable, maintaining a calm demeanour and carefree attitude.
Psychoticism
Those high in psychoticism tend to be insensitive, unconventional and lack a developed conscience. Eysenck argued that most people would score low on this dimension, with the distribution being less even compared to the other two traits.
The Eysenck personality questionnaire
Eysenck developed the Eysenck Personality Questionnaire (EPQ) to measure these three dimensions. The full version contains approximately 100 items, with a shorter 48-item version also available.
Sample EPQ Questions:
Extraversion:
- Do you like to talk a lot?
- Are you rather lively?
Neuroticism:
- Do you worry about things that might happen?
- Are your feelings rather easily hurt?
Psychoticism:
- Do you seem to get into a lot of fights?
- Would you enjoy practical jokes that could sometimes really hurt people?
Biological basis to the theory
Eysenck believed that personality traits had biological foundations and were largely inherited, suggesting that criminals are essentially born with personalities that predispose them to offending behaviour.
Extraversion and the brain
The biological basis for extraversion lies in cortical arousal levels in the brain. The reticular activating system (RAS) regulates activation levels. Eysenck compared this to a car engine - when activation is low, individuals seek environmental stimulation to reach optimal functioning levels.
Extraverts naturally have lower brain arousal and therefore seek stimulation from their environment, whilst introverts have higher baseline arousal and prefer to avoid overstimulation.
Neuroticism and the nervous system
Neuroticism relates to the autonomic nervous system. Some individuals react more swiftly and intensely to stress, and Eysenck argued that those scoring high on neuroticism respond more quickly and to a greater degree to stressful situations.
Psychoticism and hormones
Eysenck provided less detail about the biological basis of psychoticism, though he suggested that male hormones such as testosterone might be involved in this dimension.
Eysenck's theory applied to criminal behaviour
The theory proposes several key principles when applied to criminality:
Core Principles of Criminal Personality Theory:
- Offenders display distinctive personality traits or behavioural patterns
- These personality traits have a genetic foundation
- Faulty development of conscience can prevent individuals from controlling their offending behaviour
How each trait contributes to criminality
High extraversion makes individuals more likely to commit crimes because they are sensation seekers who may be drawn to the thrill and excitement of criminal activities. Their impulsive nature means they are less likely to consider consequences before acting.
High neuroticism contributes to criminality because these individuals experience intense emotions and may be more likely to commit crimes during emotionally charged situations. Their responsive autonomic nervous system makes them more easily conditioned, potentially leading to learned criminal behaviours.
High psychoticism increases criminal likelihood because these individuals are aggressive, lack empathy, and have underdeveloped consciences. This means fewer internal barriers prevent them from harming others or breaking societal rules.
Research evidence
Furnham (1984)
This study assessed 210 participants' personalities and found that the strongest predictors of self-reported delinquency were high levels of psychoticism, followed by neuroticism, then moral guidance, extraversion, and social skills. The findings suggest some association between Eysenck's personality traits and criminal behaviour.
Farrington (1992)
Research comparing caught and convicted offenders with self-confessed criminals revealed interesting patterns. Convicted offenders showed high neuroticism and low extraversion, whilst self-confessed criminals who had not been caught displayed low neuroticism and high extraversion. This suggests that personality characteristics may differ between different types of criminals, with impulsive individuals more likely to be caught.
Heaven (1996)
A longitudinal study following 282 fourteen-year-olds over two years found that psychoticism was the best predictor of later delinquency. This provides some support for Eysenck's theory linking personality traits to criminality.
Evaluation
Strengths
Positive Aspects of Eysenck's Theory:
- The theory has generated substantial research and has empirical support from multiple studies
- It provides a clear, testable framework for understanding criminal personality
- The biological basis gives the theory scientific credibility
Weaknesses
Mixed research support: Studies do not consistently support all three traits as predictors of criminality. Results for extraversion are particularly mixed, possibly because different types of crimes attract different personality types. For example, extraverts may be drawn to exciting crimes that raise adrenaline, but if these aren't measured in research, their criminal tendencies may be missed.
Deterministic implications: The argument that personality is inherited and predisposes individuals to crime raises serious questions about personal responsibility and culpability. If someone is born with a criminal personality, this challenges fundamental assumptions of the legal system about individual choice and accountability.
Sample bias: Eysenck has been criticised for developing his theory using samples that may not adequately represent the general population. This means specific personality types might appear more dominant than they actually are in the broader community.
Key Points to Remember:
- Eysenck's theory proposes three personality traits (extraversion, neuroticism, psychoticism) that combine to predict criminal behaviour
- Each trait has a biological basis: extraversion relates to brain arousal, neuroticism to the nervous system, and psychoticism to hormones
- High scores on all three traits supposedly increase criminal likelihood through different mechanisms
- Research evidence is mixed, with some support but inconsistent findings across all three traits
- The theory raises important questions about free will and moral responsibility in criminal behaviour