Forgetting what you have checked: a link between working memory impairment and checking behaviors in obsessive-compulsive disorder.
INTRODUCTION The most recent neuroscientific studies have provided evidence about the existence of structural and functional abnormalities in fronto-estriatal circuits among patients with obsessive-compulsive disorder (OCD). Those abnormalities have also been proposed as the explanation for cognitive deficits and clinical symptoms of patients with OCD. In this paper we present a review of studies that have examined the neurocognitive functioning (attention, memory and executive functions) of patients with OCD. DEVELOPMENT Studies show mixed results in terms of selective attention and processing speed. With regards to executive functions, patients with OCD display deficit to change the focus of attention, problems in response inhibition and difficulties to generate planning strategies. Studies assessing memory indicate that these patients present an evident deficiency in non-verbal memory, while is not so clear in verbal memory. This memory deficit seems to be related to the lack in the use of effective strategies, the need for excessive testing and the appearance of the doubt. CONCLUSIONS The vast heterogeneity of the disorder and the limitations of some studies, which do not control the influence of variables such as comorbidity and medication, do not allow more definitive conclusions. Anyway, executive functions deficit seems to be the more consistent neuropsychological deficit in OCD. Future studies should focus on the control of extraneous variables, as well as on the relationship between the cognitive processes and symptoms of OCD.