An investigation of the relationship between psychopathy and greater gray matter density in lateral prefrontal cortex.

Psychopathic traits predispose individuals toward antisocial behavior. Such antagonistic acts often result in "unsuccessful" outcomes such as incarceration. What mechanisms allow some people with relatively high levels of psychopathic traits to live "successful", unincarcerated lives, in spite of their antisocial tendencies? Using neuroimaging, we investigated the possibility that "successful" psychopathic individuals exhibited greater development of neural structures that promote "successful" self-regulation, focusing on the ventrolateral prefrontal cortex (VLPFC). Across two structural magnetic resonance imaging studies of "successful" participants (Study 1: N = 80 individuals in long-term romantic relationships; Study 2: N = 64 undergraduates), we observed that gray matter density in the left and right VLPFC was positively associated with psychopathic traits. These preliminary results support a compensatory model of psychopathy, in which "successful" psychopathic individuals develop inhibitory mechanisms to compensate for their antisocial tendencies. Traditional models of psychopathy that emphasize deficits may be aided by such compensatory models that identify surfeits in neural and psychological processes.