A meta-analytic review of Wisconsin Card Sorting Test and verbal fluency performance in obsessive-compulsive disorder

Abstract

Introduction. Abnormalities in associative frontostriatal circuits are often associated with obsessive-compulsive disorder (OCD), leading many researchers to predict that executive dysfunction should be particularly pronounced. However, deficits on putative tests of this construct have not consistently been identified. Methods. The present study used quantitative techniques to integrate results from 32 studies that assessed OCD patients' performance on tests of phonemic fluency, semantic fluency, and/or the Wisconsin Card Sorting Test (WCST). Results. As has been found for patients with focal frontal (but not focal nonfrontal) cortical lesions, relative to healthy controls OCD patients were comparably impaired on tests of phonemic and semantic fluency (r s =.33 and.37, respectively). However, in contrast to patients with focal frontal lobe injuries, fluency deficits did not qualify as differential deficits relative to psychomotor speed. Moreover, although a prominent view in the literature is that set-shifting is particularly compromised, the WCST was less sensitive to the presence of OCD than phonemic and semantic fluency, and also failed to qualify as a differential deficit. Conclusions. For patients with OCD, deficits on tests of verbal fluency and the WCST do not appear to reflect executive dysfunction, but are instead consistent with a more generalised cognitive impairment.