RESUMO
BACKGROUND: There is an overlap between the symptoms of psychopathy and autism spectrum disorders. AIM: To contribute to an adequate differential diagnosis of these disorders. METHOD: We reviewed the literature with the help of PubMed, using as key words: 'empathy', 'psychopathy', 'autism', 'aggression' and 'antisocial' for the period 1980-2004. We also consulted papers listed in the bibliographic references for these articles. RESULTS: Empathic deficit is a core symptom of both disorders. In psychopathy there are signs of an emotional empathic deficit, an inability to feel along with another person (insensitivity). Research into autism spectrum disorders points to a cognitive empathic deficit, an inability to take the perspective of another person (innocence). The antisocial behaviour that can accompany both disorders might be due to the type of empathic deficit. In psychopathy the antisocial behavior often involves insensitive manipulation and exploitation ofanother person. In autism spectrum disorders there is sometimes antisocial behaviour which could be caused partly by incorrect evaluation of social situations. In both psychopathy and autism spectrum disorders dysfunctioning of the orbitoftontal cortex and the amygdala is often mentioned as a possible cause of empathic deficit. CONCLUSION: An accurate diagnosis of the type of empathic deficit involved could help to differentiate psychopathy from autism spectrum disorders. Good diagnostic tools are not yet available.