Researchers from Queen’s, McMaster, Lethbridge and Saskatchewan are challenging the commonly held belief that psychopaths suffer from a mental disorder. Their new study is published in Frontiers of Psychology. From Queen’s University:
Historically, psychopaths – people who are uncaring about others, extreme risk-takers, and often commit strings of violent crimes – were thought to be mentally disordered.
However, a study led by Queen’s University postdoctoral fellow Daniel Krupp supports more recent thinking, from the perspective of evolutionary psychology, that psychopaths may not be disordered after all. Rather, psychopathy may have evolved to exploit others.
Mental disorders pose an increased risk that people will hurt their kin, but evolutionary theory predicts that mentally healthy people will tend to avoid hurting their genetic relatives. The Queen’s-led study examined 289 cases of violent offenders at a mental health centre in Ontario. Evidence from the study indicates that offenders with a greater degree of psychopathy were actually less likely to hurt their genetic relatives than those with a lesser degree of psychopathy.
“It’s a counterintuitive and surprising finding, considering the impulsive and violent nature of psychopaths, who also engage in ruthlessly selfish behavior,” Dr. Krupp says. “But it makes sense in the light of evolutionary theory: individuals who have evolved to exploit others should nonetheless avoid hurting their relatives, because those relatives also carry copies of their genes.”
The study builds on previous work showing that psychopaths unexpectedly function quite well in society. If they were mentally disordered, we would expect them to have neurological problems, serious disorders like schizophrenia, difficulty interacting with others, problems of physical development, and fewer children.