Are you upset? Distinct roles for orbitofrontal and lateral prefrontal cortex in detecting and distinguishing facial expressions of emotion.

Navigating our complex social world requires effective processing of subtle emotional signals, such as those conveyed by facial expressions. Failure to do so may underlie some of the disabling social-emotional deficits common in a range of neuropsychiatric and neurological conditions. Prefrontal cortex (PFC) has long been implicated in these processes, but the particular contributions of subregions within PFC remain unclear. We used a sensitive facial emotion rating task in patients with focal lesions to different regions within PFC to identify distinct contributions of 2 prefrontal regions to recognizing emotions from facial expressions. A combination of region-of-interest and voxel-based lesion-symptom mapping established that damage to ventromedial PFC impaired the detection of subtle facial expressions of emotion. Such patients had difficulty distinguishing emotional from neutral expressions. In contrast, patients with left ventrolateral PFC were able to detect the presence of emotional signals but had difficulty discriminating between specific emotions. These effects were regionally specific: Dorsomedial prefrontal damage had no effect on either aspect of emotion recognition. These findings suggest that separable processes relying critically on distinct regions within PFC responsible, on the one hand, for detecting emotional signals from facial expressions and, on the other, for correctly classifying such signals.