Reduced prefrontal gray matter volume and reduced autonomic activity in antisocial personality disorder

Background: Major damage to gray and white matter in the prefrontal cortex and autonomic deficits have been found to result in pseudopsychopathic pers onality in patients with neurological disorders, but it is not known whethe r people with antisocial personality disorder (APD) in the community who do not have discernable brain trauma also have subtle prefrontal deficits. Methods: Prefrontal gray and white matter volumes were assessed using struc tural magnetic resonance imaging in 21 community volunteers with APD (APD g roup) and in 2 control groups, comprising 34 healthy subjects (control grou p), 26 subjects with substance dependence (substance-dependent group), and 21 psychiatric controls. Autonomic activity (skin conductance and heart rat e) was also assessed during a social stresser in which participants gave a videotaped speech on their faults. Results: The APD group showed an 11.0% reduction in prefrontal gray matter volume in the absence of ostensible brain lesions and reduced autonomic act ivity during the stresser. These deficits predicted group membership indepe ndent of psychosocial risk factors. Conclusions: To our knowledge, these findings provide the first evidence fo r 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 char acterize antisocial, psychopathic behavior.