Since the great majority of patients with depressive syndromes and character disorders are successfully treated in an outpatient setting, the Branch has placed a major emphasis on developing an outpatient facility for the clinical and biological evaluation and treatment of these patients. A comprehensive psychobiological evaluation of depression spectrum illnesses is performed, including psychological testing, circadian rhythm monitoring of temperature and activity, sleep electroencephalograms, TRH infusions, dexamethasone suppression tests, and collections of blood, urine, and cerebrospinal fluid. The treatment involves random assignment to either tranylcypromine or desipramine, with studies repeated following treatment with medication. A study of the neurophysiology of borderline syndromes, including a multi-drug cross-over study, has begun this year. In addition, small scale studies of the effects of tranylcypromine on rapid-cycling bipolar illness and the effects of a vasopressin analog on ECT- induced memory loss have been initiated. The role of lithium in the treatment of depressive pseudodementia and the occurrence of life-threatening pneumomediastinum as a complication of manic psychosis have been described in case reports.