IN PSYCHOPATHS, HIGHER IQ CORRELATES WITH GREATER SEVERITY

In 1941, Hervey Cleckley published The Mask of Sanity, the first psychiatric description of psychopaths- dangerous people, many of them violent or white-collar criminals, who exhibit shallowness and narcissism, callousness and lack of empathy, impulsiveness, a lack of remorse, and egocentricity.

Cleckley's description has stood the test of time, except for one observation: that psychopaths, unlike other criminals, tend to be highly intelligent. Later studies revealed that in general, psychopaths have IQs similar to those of non-psychopathic lawbreakers.

A new study, however, suggests that the severity of criminality increases in psychopaths who are more intelligent-a pattern opposite to that seen in criminals who are not psychopathic.

Peter Johansson and Margaret Kerr studied 370 men sent to a Swedish nationwide assessment center for violent offenders. Forty percent of the men were convicted of murder, attempted murder, or manslaughter.

The researchers report, "The key finding in this study is that psychopathic and non-psychopathic criminals, although not different in overall levels of intelligence, did differ in how high intelligence was related to the seriousness of misbehavior. For non-psychopaths, higher intelligence, particularly verbal intelligence, meant a later start in violent crime. For those diagnosed as psychopaths, however, high intelligence meant an early start in violent offending and more problematic behavior in and outside of institutions."

The researchers say that while psychopaths are not more intelligent than non-psychopaths as Cleckley suggested, high intelligence appears to "enhance the destructive potential" of a psychopath. They speculate, "[P]erhaps an explanation lies in the experience of having high intellectual abilities together with characteristics such as impulsivity and irresponsibility that do not allow one to succeed in the ways that people with high intellectual abilities normally do."

"Psychopathy and intelligence: a second look," Peter Johansson and Margaret Kerr, Journal of Personality Disorders, Vol. 19, No. 4, 2005, 357-69. Address: Peter Johansson, Center for Developmental Research, Department of Behavioral, Social and Legal Sciences, Örebro University, SE-701 82 Örebro, Sweden, peter.johansson@bsr.oru.se.