Visuospatial priming and stroop performance in patients with obsessive compulsive disorder.

Two laboratory measures of competitive information processing were studied in obsessive compulsive disorder (OCD) and normal control participants to assess the effects of priming and interfering information on response latency or speed. In the visuospatial priming (VSP) task, key press latency is facilitated or inhibited, depending on the spatial location of a priming cue. In the Stroop task, participants name the ink color of printed words that have an interfering semantic value. OCD participants displayed significantly slowed baseline response latency and increased facilitory priming scores in the VSP task, with no significant difference in VSP inhibition compared with control participants. Higher interference cost in the Stroop task was also observed in OCD participants. Clinical associations between VSP and Stroop performance and specific OCD symptoms were examined. Increased VSP facilitation was most pronounced in OCD participants who reported a history of violent images, tics, "just right" obsessions, or checking compulsions.