Brain imaging research in psychopathy is beginning to reveal functional and structural abnormalities in these individuals. Theories have been proposed suggesting the existence of brain structural abnormalities in psychopathy. Damasio (1994) proposed a somatic marker theory which identifies orbitofrontal deficits as a strong candidate for the development of psychopathy. An alternative theory developed by Blair (2003) speculated that amygdala abnormalities may account for the emotional deficits observed in psychopaths. However, very few studies to date have attempted to evaluate the structural integrity of these brain areas in psychopathic individuals. Using a community sample of 194, state-of-the-art computational image analysis methods will be employed to isolate the neuroanatomical mechanism which may predispose to psychopathy.
The first aim of this study is to examine the hypothesis that psychopaths will show gray matter reduction in dorsolateral prefrontal and orbitofrontal regions compared to controls. Second, psychopaths will show global or/and localized amygdala reduction compared to controls. Third, unsuccessful psychopaths (caught) will show greater dorsolateral prefrontal and orbitofrontal gray matter reductions compared to successful psychopaths (not caught) and controls. However, the amygdala volume reduction is expected to be found in both successful and unsuccessful psychopaths. Fourth, it is predicted that antisocial and lifestyle facets of psychopathy will be correlated with reduced dorsolateral prefrontal volume while affective facet will be correlated with reduced amygdala and orbitofrontal volume. Volumetric segmentation and cortical pattern matching methods will be applied to structural Magnetic Resonance Imaging (MRI) data to identify volumetric and morphological differences in cortical and subcortical structures across groups. The training plan will have a central focus on the assessment of psychopathy, MRI techniques, and computational image analysis. This proposed study attempts to capitalize on what is believed to be a novel community sampling approach to break new ground in our understanding of the neuroanatomical basis of psychopathy.
Although psychopathy represents an enormously costly health problem, research to date on neuroanatomical factors is very limited. By uncovering the neural basis of psychopathy, this proposal will hopefully provide valuable scientific knowledge that will facilitate the development of prevention and treatment of this disorder. ? ? ?
