Objective: The biological basis of psychopathy remains to be fully elucidated. Evidence suggests a genetic contribution and dysfunction of the serotonin system. The objective of this article is to review the contribution of the neuroimaging of the last decade to our understanding of psychopathy.
Method: A literature search was conducted using PubMed and the words psychopath, antisocial personality disorder, dissocial personality disorder, violence, image and imaging. In addition, the reference lists of the identified papers, and recent textbooks, were perused for additional sources.
Results: Five structural and 15 functional neuroimaging studies were selected and examined. Structural studies have reported decreased prefrontal grey matter, decreased posterior hippocampal volume and increased callosal white matter, but to this point, these have not been replicated. Functional studies suggest reduced perfusion and metabolism in the frontal and temporal lobes. Abnormalities of function have been reported, predominantly in frontal and temporal lobe structures during classical conditioning and response inhibition tasks, and in the processing of emotional words and pictures.
Conclusion: Functional neuroimaging strongly suggests dysfunction of particular frontal and temporal lobe structures in psychopathy. However, there are difficulties in selecting homogeneous index cases and appropriate control groups. Further studies are necessary. Responses depend on genetic endowment, early life experience, the sociocultural context and the significance of any stimulus to the individual.