[The contribution of forensic neuroscience to psychopathy]

Psychopathy is a construct characterized by symptoms of emotional detachment, a lack of empathy, guilt and remorse, irresponsibility and a propensity for impulsive behavior. This article critically evaluates the contribution of structural and functional neuroimaging to the understanding of this personality disorder in North American forensic populations with psychopathic traits. Neuroimaging results are highly variable. They report numerous structural and functional abnormalities that are not limited to the amygdala and the ventromedial prefrontal cortex but include the striatum, hippocampus, and uncinate fasciculus. These brain abnormalities underlie an attenuated emotion processing functioning (but not an absence) and aversion to negative and threats signals, reinforcement learning, representation of rewards and modulation of attention that have an impact in decision-making, caring for others, and moral judgment. It is important to note that the neuroanatomical, neurofunctional, and behavioral differences between individuals with high psychopathic traits and those with low traits are highly heterogeneous and of degree rather than of nature.