Neuroimaging data from incarcerated criminals suggests that psychopathy is related to abnormalities in the prefrontal cortex of the brain.

“Individuals with psychopathy account for a disproportionate amount of crime in the United States,” the study’s corresponding author, Cole Korponay of the University of Wisconsin-Madison, told PsyPost. “Though they only comprise about 1% of the population as a whole, individuals with psychopathy make up between 15-25% of the prison population and are estimated to be responsible for nearly $460 billion in criminal social costs annually.”

“We wanted to examine if these individuals have brain abnormalities that may relate to their deficits in self-control and pro-social decision-making, with the hope that a better understanding of what’s going on under the hood can help spur treatment development.”

The study was published April 11, 2017 in the peer-reviewed open access journal Social Cognitive and Affective Neuroscience.

The researchers used MRI scans to examine the prefrontal cortex of 124 inmates from a medium-security Wisconsin correctional facility. The inmates were tested for psychopathic traits using the Psychopathy Checklist Revised, a diagnostic questionnaire used to measure a person’s antisocial tendencies.

The researchers found that psychopathic traits were associated with larger gray matter volumes in the prefrontal cortex, an area of the brain involved in planning, decision making, working memory and learning. They also found that psychopathic traits were correlated with greater connectivity between subregions of the prefrontal cortex, such as between the left middle frontal gyrus and right inferior frontal gyrus.

“We found that prison inmates with the most severe impulsive and antisocial psychopathic traits had the highest amount of gray matter in their prefrontal cortex – an area of the brain crucial for self-control and pro-social decision-making,” Korponay explained. “We also found that brain activity between different areas of the prefrontal cortex was more highly coupled in these individuals. Overall, the findings suggest that individuals with psychopathy have abnormal structure and function of the prefrontal cortex; these abnormalities may be related to the deficits in self-control and pro-social decision-making observed in these individuals.”

But researchers still have more to learn about the correlation between psychopathy and the prefrontal cortex.

“It is still unclear how these abnormalities come to be. Future studies can examine potential genetic and environmental factors that may cause abnormal development of the prefrontal cortex in individuals with psychopathy,” Korponay said.

The study, “Impulsive-antisocial psychopathic traits linked to increased volume and functional connectivity within prefrontal cortex“, was also co-authored by Maia Pujara, Philip Deming, Carissa Philippi, Jean Decety, David S. Kosson, Kent A. Kiehl, and Michael Koenigs.

