A Neuro-psychological Model of Violence Propensity in Schizophrenia

Abstract

Introduction Schizophrenia is associated with an increased risk of violence. The successful identification of the illness specific factors that contribute to that risk could lead to the development of novel therapeutic risk management strategies. Objectives/Aims To identify cognitive and emotion processing deficits that are linked to violence risk in schizophrenia. Methods Fifty male patients with DSM-IV schizophrenia and thirty-nine healthy controls were assessed across a range of intellectual, executive, emotion and social processing domains. Lifetime propensity to violence was quantified in terms of frequency, severity and victim outcome. Results General intellectual ability and memory were not significantly associated with violence propensity. Violent patients showed significantly poorer response inhibition, after accounting for relevant clinical variables. A greater lifetime propensity to violence was associated with an attentional bias towards anger, a heightened sensitivity to the recognition of fear, with poorer complex Theory of Mind performance. Conclusions Our results allow us to propose a hypothetical model of the risk of violence in schizophrenia. We suggest that heightened sensitivity to environmental negative emotional cues and poorer understanding of complex social situations, combined with a poorer ability both to quickly process but also inhibit pre-potent responses, results in a greater propensity to violence in schizophrenia. We propose that this model sits alongside risk associated with other factors such as illicit drug use. These findings need replication but could have implications for more effective treatment and management of patients with schizophrenia.