Violent psychopaths do not understand punishments the way most people do, according to a new study.
Magnetic resonance imaging (MRI) scans taken of violent offenders who were diagnosed as being psychopathic revealed severe abnormalities in several areas of their brains. Some of the areas with the greatest damage are regions associated with learning from punishments.
"Psychopathic offenders are different from regular criminals in many ways. Regular criminals are hyper-responsive to threat, quick-tempered and aggressive, while psychopaths have a very low response to threats, are cold, and their aggressively is premeditated," Nigel Blackwood, a researcher affiliated with King's College London, said.
Brain abnormalities appear to be present in both regular offenders, as well as psychopathic individuals. However, patterns are distinctive between the two sets of criminals.
Researchers examined the brains of 50 people - 20 exhibited antisocial behavior without psychopathy, 12 had both conditions, and 18 healthy subjects served as a control group. Subjects in the study were asked to complete a game of matching cards. Points were sometimes awarded for correct matches, while they were withheld at other times. The study found that psychopathic patients reacted differently than others to the task, in light of changing conditions of the game.
"One in five violent offenders is a psychopath. They have higher rates of recidivism and don't benefit from rehabilitation programmes. Our research reveals why this is and can hopefully improve childhood interventions to prevent violence and behavioural therapies to reduce recidivism," Sheilagh Hodgins of the University of Montreal, stated in a press release.
Human brains are composed of white and grey matter. Grey matter is primarily involved in cognition and information processing, while white matter directs information flow around the neural network. Violent psychopaths were found to exhibit defects within both forms of brain matter.
Grey matter regions involved in processing of empathy, guilt, and moral reasoning were reduced in psychopathic patients. White matter areas critical for feelings of empathy were also found to be abnormal in those with psychopathic diagnoses.
Researchers in the study believe that psychopathic subjects may only recognize the positive rewards they will experience from an action they are considering, ignoring potential negative consequences.
Violent criminals, including those with psychopathy, often start experiencing antisocial behaviors when they are children and adolescents. Recognition of characteristic abnormalities in brain structures could assist health professionals and social workers in treating at-risk populations at a young age. Psychopathic individuals are also more likely than the general population to return to prison, after serving out a sentence. Investigators hope their discovery could help reduce these recidivism rates and associated costs.
