Neurocognitive function in paediatric obsessive-compulsive disorder.

Objectives: The small body of neuropsychological research in paediatric obsessive-compulsive disorder (OCD) yields inconsistent results. A recent meta-analysis found small effect sizes, concluding that paediatric OCD may not be associated with cognitive impairments, stressing the need for more research. We investigated neuropsychological performance in a large sample of youths with OCD, while assessing potential moderators.

Methods: Participants with OCD (n = 102) and matched controls (n = 161) were thoroughly screened and blindly evaluated for comorbidities, and completed a neuropsychological battery assessing processing speed, visuospatial abilities (VSA), working memory (WM), non-verbal memory (NVM), and executive functions (EF).

Results: Compared to controls, youths with OCD exhibited underperformance on tasks assessing processing speed. On tests of VSA and WM, underperformance was found only on timed tasks. There were no differences on NVM and EF tasks. Notably, the OCD group's standardised scores were in the normative range. Test performance was not associated with demographic or clinical variables.

Conclusions: Youths with OCD exhibited intact performance on memory and EF tests, but slower processing speed, and underperformance only on timed VSA and WM tasks. While the OCD group performed in the normative range, these findings reveal relative weaknesses that may be overlooked. Such an oversight may be of particular importance in clinical and school settings.