QUANTITATIVE EEG IN OBSESSIVE-COMPULSIVE DISORDER

Electroencephalograms (EEGs) were recorded from 13 unmedicated and non depressed patients with DSM-III-R obsessive-compulsive disorder (OCD) and from 10 age-matched controls. All subjects were also administered the Wechsler Memory Scale Delayed Logical Memory and Delayed Visual Re production tests. Quantitative analysis of the EEG revealed lower log absolute power in the delta, beta 1, and beta 2 bandwidths for OCD pat ients at frontal and right-hemisphere locations. OCD patients displaye d greater hemispheric asymmetries in EEG activity based on difference measures of EEG power from homologous electrode pairs, indicative of s evere right hemisphere EEG hypoactivity. Standardized measures of hemi spheric asymmetry for the beta 2 bandwidth accurately predicted group membership and were correlated both with poorer patient performance on the visual-spatial memory task and better performance on the verbal m emory task. OCD patients were significantly impaired on the visual-spa tial task, but not on the verbal memory test, relative to controls.