A Neurocognitive Comparison of Pediatric Obsessive-Compulsive Disorder and Trichotillomania (Hair Pulling Disorder)

Obsessive-compulsive disorder (OCD) and trichotillomania (hair pulling disorder, HPD) are both considered obsessive-compulsive and related disorders due to some indications of shared etiological and phenomenological characteristics. However, a lack of direct comparisons between these disorders, especially in pediatric samples, limits our understanding of divergent versus convergent characteristics. This study compared neurocognitive functioning between children diagnosed with OCD and HPD. In total, 21 children diagnosed with HPD, 40 diagnosed with OCD, and 29 healthy controls (HCs), along with their parents, completed self-/parent-report measures and a neurocognitive assessment battery, which included tasks of inhibitory control, sustained attention, planning, working memory, visual memory, and cognitive flexibility. A series of analyses of variance (or covariance) indicated significant differences between groups on tasks examining planning and sustained attention. Specifically, children in both the OCD and HPD groups outperformed HCs on a task of planning. Further, children with OCD underperformed as compared to both the HPD and HC groups on a task of sustained attention. No between group differences were found with respect to tasks of reversal learning, working memory, spatial working memory, visual memory, or inhibitory control. The implications these findings may have for future, transdiagnostic work, as well as limitations and future directions are discussed.