A recent study compared the IQ profiles of 82 children and adolescents with obsessive-compulsive disorder (OCD) against 82 typically developing peers, matched for age, sex, handedness, and education. The headline finding: overall intellectual ability (Full-Scale IQ) and Verbal IQ were essentially the same between the two groups, both landing comfortably in the average range (90-110). So the idea that OCD broadly impairs general intelligence in kids doesn’t hold up here.
Where things got interesting was in Performance IQ—the non-verbal, visuospatial side of the WASI test. Youth with OCD scored modestly but significantly lower on this measure, and the gap between their Verbal and Performance scores was notably wider than in the comparison group. Digging deeper, the researchers traced most of this difference to a specific subtest called Block Design, which asks kids to replicate patterns using colored blocks, a task that leans heavily on visuospatial reasoning. Importantly, this gap held up even after controlling for processing speed and other co-occurring conditions, suggesting it isn’t just a byproduct of kids moving or thinking more slowly, but something more specific to how OCD affects visuospatial processing.
What makes this study notable is that it mirrors a pattern long seen in adults with OCD, now replicated in a pediatric sample, hinting that this Verbal/Performance IQ discrepancy might be a stable trait of the disorder rather than something that develops with age or illness duration. The researchers also note a possible real-world implication: this pattern might help explain why OCD has been linked to lower educational attainment in other research, though they’re careful to flag that average-range IQ scores don’t fully square with that academic gap, meaning things like symptom burden or functional impairment likely play a role too. As always, more research (especially longitudinal work) is needed to sort out cause and effect.
Link to full study: Redirecting