Cognitive dysfunction in childhood-onset pathologic skin picking

Abstract

ObjectiveThere has been little research examining cognitive correlates of childhood-onset pathologic skin picking. MethodsOf 50 subjects with Pathological Skin Picking (PSP), 24 (48%) (mean age 32.3±12.2 years; PSP onset at 7.67±2.54 years; 87.5% female) reported onset of skin picking before age 11 years. These subjects were compared to 26 subjects with later onset of picking after age 11 years (mean age 34.2±14.5 years; PSP onset 18.04±9.51 years; 92.3% female) on measures of symptom severity, comorbidity, and social functioning. Both groups undertook cognitive assessments using the Stop-signal task (assessing response impulsivity) and the Intra-dimensional/Extra-dimensional (ID/ED) Set Shift task (assessing cognitive flexibility). ResultsThere were no significant clinical differences based on age of PSP onset. Early and later onset PSP showed significantly prolonged stop-signal reaction times (i.e., worse inhibition) versus healthy controls, but, contrary to our hypothesis, only the later onset patients manifested significantly elevated errors on the set-shifting task versus controls (i.e., cognitive inflexibility: total errors corrected and errors for the extradimensional shift stage). ConclusionThese results indicate overlapping clinical features and impulse dyscontrol between early and later onset PSP, but heterogeneity with respect to set-shifting dysfunction. Future work should explore possible subgroups in PSP and whether age of onset and cognitive functioning is predictive of treatment outcomes.