An international team of scientists has shown that psychopathy negatively affects the level of intelligence. The results of the work have been published on the bioRxiv preprint server.
Psychopathy is a syndrome that is expressed in a combination of personality traits such as manipulativeness, inability to empathize and sincere remorse for harming other living organisms. In popular culture, such as cinema, characters with psychopathy are often portrayed as highly intelligent - and a number of studies support the link between the syndrome and thinking.
However, the exact nature of this correlation has not been sufficiently studied. To fill the gap, researchers at the University of Cambridge and other universities conducted a meta-analysis of 187 studies on the relationship between psychopathy and intelligence, conducted from 1941 to 2015. The total sample size was 9010 people with an average age of 32.2 years. Some of them (4321 people) showed antisocial behavior.
The results showed that the majority (57 percent) of antisocial personalities were criminal psychopaths. More often, the intelligence of psychopaths was studied using the culturally independent Cattell test (CFT20-R), Wechsler test (WAIS), or Raven's matrices (for abstract thinking). The first two showed insignificantly reduced intelligence in psychopaths, the last - normal intelligence.
According to the authors, these data indicate that the portrayal of psychopaths as predominantly intellectual individuals is not true. More characteristic traits for psychopaths are impulsiveness, propensity to criminal actions and auto-aggression. Meanwhile, in a number of cases, such people achieve a high social status, despite their low intelligence.
Denis Strigun