Decoding of facial expression of emotion in criminal psychopaths.

To examine whether psychopaths exhibit specific deficits in nonverbal emotional processing, 20 criminal psychopaths, 23 criminal nonpsychopaths, both groups identified with Hare's (2003) Psychopathy Checklist-Revised, and 25 noncriminals completed the facial affect recognition test developed by Philippot et al. (1999). All participants were males. The criminal psychopaths and nonpsychopaths were confined in a high-security prison. Forty slides were presented on a computer screen, each representing a male or a female actor portraying facial expressions of happiness, anger, sadness, fear, or disgust. Facial stimuli varied in emotional intensity (0%, 30%, 70%, and 100%). Overall, both criminal groups were less accurate than controls in decoding facial expression of emotion. Analysis of covariance showed that this effect is accounted for by differences in level of education of the participants. While criminal nonpsychopaths did not differ from criminal psychopaths in term of overall accuracy, they were less accurate for amygdalian emotion than for nonamygdalian ones. Criminal psychopaths' performance, however, was not affected by the amygdalian nature of the facial display. This pattern of results is opposed to the Blair's amygdalian hypothesis.