Neuropsychological testing has revealed that affectively ill patients have impaired performance on the Halstead Category Test and recognition of facial emotional expression, in contrast with unimpaired verbal emotion recognition tasks. The impairment in facial emotion recognition is state-related; i.e., more profound during depression than the """"""""well- interval"""""""" between episodes. Patients also report lifetime disturbances in tasks and activities of daily living including visual spatial processing, but not those in the verbal mode. The neural substrates of these deficits are systematically being explored by a variety of techniques including testing patients utilizing 015 blood flow studies with PET methodology (see MH 02636-02 BP and MH 02638-02 BP). CAT scan studies have revealed increased VBR in patients with affective disorders unrelated to the course of illness, but positively related to age, measures of cortisol hypersecretion, and impairment on the Halstead Category Test. MRI studies suggest decreased area and volume of the temporal lobe in affectively ill subjects compared with controls. Periventricular abnormalities have been observed in BPI patients on T2 weighted scans; these findings are of interest in relation to increase in CSF protein in BPI patients as well. Evidence of frontal hypometabolism is revealed on PET scan studies in patients with primary affective disorders as well as depression associated with epilepsy. Temporal and parietal alterations are also evident.