Psychopaths are usually diagnosed by their behavioral patterns: an eccentric personality, including lack of empathy and remorse, deceptiveness, and abusive actions. Now, researchers have shown that psychopaths also have differences in particular brain regions, with fewer connections between the ventromedial prefrontal cortex (vmPFC), a brain region involved in feelings of empathy and guilt, and the amygdala, which mediates fear and anxiety, according to a study published in the November 30 issue of Journal of Neuroscience.
Michael Koenigs, assistant professor of psychiatry in the University of Wisconsin School of Medicine and Public Health, and his colleagues scanned the brains of 40 inmates at a medium-security prison in Wisconsin, and compared those with psychopathy to those who had been convicted of similar crimes but did not have clinical psychopathy. The researchers used diffusion tensor images (DTI) to visualize the white matter fibers connecting the vmPFC and amygdala and functional magnetic resonance images (fMRI) to visualized neuronal activity. They found reduced structural integrity in the vmPFC-amygdala connections and less coordinated activity between the two brain regions.
“Those two structures in the brain, which are believed to regulate emotion and social behavior, seem to not be communicating as they should,” Koenigs said in a press release Indeed, previous work has shown that psychopaths make decisions similarly to patients with damage to their vmPFC.
“The combination of structural and functional abnormalities provides compelling evidence that the dysfunction observed in this crucial social-emotional circuitry is a stable characteristic of our psychopathic offenders,’’ added co-author Joseph Newman, a psychology professor at UW. “I am optimistic that our ongoing collaborative work will shed more light on the source of this dysfunction and strategies for treating the problem.”