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Schizophrenia Patients With a History of Severe Violence Differ From Nonviolent Schizophrenia Patients in Perception of Emotions but Not Cognitive Function

J Clin Psychiatry 2005;66(3):300-308

Background: Impaired processing of emotions may relate to violent behavior in schizophrenia patients. We compared emotional function in schizophrenia patients with and without a history of severe violent behavior.

Method: Tests of identification and differentiation of facial emotions were performed to compare 35 patients with chronic schizophrenia or schizoaffective disorder (DSM-IV criteria) and a history of severe violent behavior with 35 nonviolent schizophrenia patients and 46 healthy controls. Tests of executive function, attention, visual orientation, working memory, memory for faces and objects, and motor function were also administered.

Results: Violent and nonviolent schizophrenia patients showed impaired emotional and cognitive function compared with controls. Violent patients showed a significantly better ability to identify facial emotional expressions but a poorer ability to discriminate between intensity of emotions than nonviolent schizophrenia patients. There was no difference in cognitive performance between the 2 patient groups.

Conclusion: Violent schizophrenia patients may have a better ability to identify facial emotional cues than nonviolent schizophrenia patients but may be less able to assess the intensity of these cues. This trait may contribute to conflict generation and failure to recognize resolution signals, leading to conflict escalation and violence in violence-prone schizophrenia patients.