Neuropsychological deficits and treatment response in obsessive-compulsivedisorder

Neuropsychological investigations of patients with obsessive-compulsive dis order (OCD) have shown inconsistent results. The present study tested the h ypothesis that only a subgroup of patients with OCD actually shows neuropsy chological deficits. Due to a stronger involvement of brain organic factors in the disorder, this subgroup was expected to be characterized by a poore r treatment response. 24 inpatients with OCD were examined before and after 9 weeks of behavior t herapy. According to their decrease in severity of symptoms the patients we re differentiated in 'Minor Responder' (n = 11) and 'Major Responder' (n = 13). Both groups did not differ in age, general intelligence, sex or handed ness. The severity of symptoms before treatment was similar in both groups. Compared to normal controls (n = 13) matched for age, general intelligence , sex, and handedness, the group of 'Major Responders' did not show any neu ropsychological deficits. The group of 'Minor Responders', however, was sig nificantly impaired in three neuropsychological measures ('Paired-associate learning, visual', 'Verbal fluency, formal' and 'Verbal fluency, semantic' ) compared to normal controls before and also after treatment. These findin gs provide evidence for an effect of neuropsychological impairment on the t reatment response in OCD.