Abnormal visual event-related potentials in obsessive-compulsive disorder without panic disorder or depression comorbidity

Visual event-related potentials and spline map topography during a discrimi native response task (DRT) were studied in 8 obsessive-compulsive disorder (OCD) patients without comorbidity for panic disorder or depression and in 12 age-matched controls. In the DRT task (like in a go/no-go task) the subj ect had to press a button when the target stimuli appeared and had to retai n the response when the non-target stimulus appeared (vertical bars were in termixed with an equal probability of horizontals), OC patients had greater N1 latency than controls and their N1 and P3 amplitude was larger for the target stimuli, but not for non-target stimuli. In the normals, non-target stimuli (no-go task) produced a larger activation than target stimuli (go t ask). In the OCD patients the target stimuli produced the same large activa tion as the non-target. These findings are consistent with theories that co nsider OCD to be an attentional disorder deriving from a misallocaling of c ognitive resources. Moreover, spline map topography confirmed that P3 hyper activation is localised principally on the frontal lobes. (C) 2000 Elsevier Science Ltd. All rights reserved.