Reduced Prefrontal Gray Matter Volume and Reduced Autonomic Activity in Antisocial Personality Disorder

TLDR

Pseudopsychopathic traits in neurological patients are linked to prefrontal gray/white matter damage and autonomic deficits, yet it is unclear if community‑based antisocial personality disorder (APD) subjects without overt brain injury exhibit similar subtle prefrontal impairments. The study measured prefrontal gray and white matter volumes by structural MRI in 21 APD volunteers versus healthy, substance‑dependent, and psychiatric controls, and assessed autonomic responses (skin conductance and heart rate) during a socially stressful videotaped speech. APD participants showed an 11 % reduction in prefrontal gray matter volume and blunted autonomic activity, with these deficits independently predicting group membership and suggesting a structural basis for the low arousal, impaired fear conditioning, and decision‑making deficits characteristic of antisocial behavior.

Abstract

<h3>Background</h3> Major damage to gray and white matter in the prefrontal cortex and autonomic deficits have been found to result in pseudopsychopathic personality in patients with neurological disorders, but it is not known whether people with antisocial personality disorder (APD) in the community who do not have discernable brain trauma also have subtle prefrontal deficits. <h3>Methods</h3> Prefrontal gray and white matter volumes were assessed using structural magnetic resonance imaging in 21 community volunteers with APD (APD group) and in 2 control groups, comprising 34 healthy subjects (control group), 26 subjects with substance dependence (substance-dependent group), and 21 psychiatric controls. Autonomic activity (skin conductance and heart rate) was also assessed during a social stressor in which participants gave a videotaped speech on their faults. <h3>Results</h3> TheAPD group showed an 11.0% reduction in prefrontal gray matter volume in the absence of ostensible brain lesions and reduced autonomic activity during the stressor. These deficits predicted group membership independent of psychosocial risk factors. <h3>Conclusions</h3> To our knowledge, these findings provide the first evidence for a structural brain deficit in APD. This prefrontal structural deficit may underlie the low arousal, poor fear conditioning, lack of conscience, and decision-making deficits that have been found to characterize antisocial, psychopathic behavior.