Negative Priming in Obsessive-Compulsive Disorder and Schizophrenia: Association with Symptom Patterns

Negative priming (NP) is assumed to indicate the effect of an inhibitory mechanism in selective attention. Previous studies showed inconsistent reductions of the NP effect in patients with obsessive-compulsive disorder (OCD) and schizophrenia. The aim of the present study was to relate NP alterations in two different NP tasks with specific symptom patterns of OCD and schizophrenia patients. Twenty-eight patients with a diagnosis of OCD, 27 patients with schizophrenia, and 27 healthy comparison participants performed a spatial and an identity priming task. Robust NP effects were found in the spatial priming task across groups and symptom patterns. However, OCD patients with a predominance of obsessive thoughts as well as schizophrenia patients with predominantly positive symptoms showed no identity NP effects, whereas OCD patients who primarily presented with compulsive rituals and schizophrenia patients with predominant negative symptoms tended to have increased identity NP compared to healthy participants. It is concluded that obsessions as well as positive psychotic symptoms are related to identity NP deficits possibly reflecting a shared basic cognitive mechanism leading to deficient thought control. (C) Copyright 2013 Textrum Ltd. All rights reserved.