It has been suggested that people with psychopathic disorders lack empathy because they have deficits in processing distress cues (e.g. fearful facial expressions).

To investigate brain function when individuals with psychopathy and a control group process facial emotion.

Using event-related functional magnetic resonance imaging we compared six people scoring ⩾25 on the Hare Psychopathy Checklist–Revised and nine non-psychopathic healthy volunteers during an implicit emotion processing task using fearful, happy and neutral faces.

The psychopathy group showed significantly less activation than the control group in fusiform and extrastriate cortices when processing both facial emotions. However, emotion type affected response pattern. Both groups increased fusiform and extrastriate cortex activation when processing happy faces compared with neutral faces, but this increase was significantly smaller in the psychopathy group. In contrast, when processing fearful faces compared with neutral faces, the control group showed increased activation but the psychopathy group decreased activation in the fusiform gyrus.

People with psychopathy have biological differences from controls when processing facial emotion, and the pattern of response differs according to emotion type.