Evaluation of cognitive slowing in OCD by means of creating incongruence between lexicon and prosody

Studies indicate that patients with obsessive-compulsive disorder (OCD) have slowing in cognitive processing, especially in the presence of a conflict. This study aimed to determine whether decision and motor times in OCD patients were affected by manipulating the congruence/incongruence of lexical and prosodic aspects of commands. An experimental paradigm was designed to simulate a situation that can trigger anxiety and obsessions in OCD patients. Commands with or without a conflict, that is. an incongruence between lexical and prosodic aspects, were given to the participants. Decision time, motor time and errors were the main parameters of the experiment. The control group had significantly faster decision times than the OCD group in response to both conflicting and non-conflicting commands. The OCD patients demonstrated higher trait anxiety, while Stroop interference and state anxiety were not significantly different between the groups. These results suggest that OCD patients experience slowing in their response times, regardless of whether the stimuli are conflicting or not. (C) 2009 Elsevier Ireland Ltd. All rights reserved.