Asked by: Belinda Anstey, Doncaster
Many of the sort of people who the media and general public would probably consider ‘evil’ – such as murderers and other violent offenders who lack remorse – would not be labelled as such by psychologists, who strive for the objectivity of a scientist.
Instead, psychologists would describe these immoral, sadistic individuals as high scorers on the personality trait of ‘psychopathy’, which consists of an interpersonal component (lying and manipulativeness), an emotional component (callousness and lack of emotion), and a behavioural component (violence and criminality).
A couple of years ago, researchers at King’s College London and Imperial College London conducted a systematic review of 24 studies involving thousands of pairs of twins who had been assessed using measures of psychopathy. The researchers concluded that all three aspects of psychopathy are heritable (passed on through the genes inherited from one’s parents) – and that the aspect with the strongest genetic predisposition is the callousness/unemotional element.
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