A compensatory mirror cortical mechanism for facial affect processing in schizophrenia

When primates passively observe other subjects perform specific gestures or actions, premotor and motor cortical areas involved in the internal representation and actual execution of those actions exhibit neuronal activation. This mirror mechanism matches observation, representation, and execution, facilitating internal motor rehearsal, imitation, recognition of actions by others and their meanings, and social learning. Schizophrenic patients have deficits in processing affect displayed by other people's faces, which likely relates to the poor social adaptation and functioning seen in the condition. We hypothesized that, when correctly performing working-memory tasks requiring facial affect processing, schizophrenic patients would show relative increased activity in brain areas involved in social learning and in the internal representation of facial expressions when compared to controls. We used functional magnetic resonance imaging in schizophrenic patients and normal controls to detect relative changes of bloodflow in cortical areas related to the representation of facial expressions while the subjects performed simple working-memory tasks with facial emotion diagrams or color circles as cites. We found that, when the task cites were facial expressions in contrast to color circles, the schizophrenic group exhibited increased activation of the face movement areas in motor and premotor cortex. [Neuropsychopharmacology 25:915-924, 2001] (C) 2001 American College of Neuropsychopharmacology. Published by Elsevier Science Inc. All rights reserved.