Seventy-eight nondemented elderly depressed patients underwent an extensive battery of cognitive tess both before and after seven weeks of treatment with nortriptyline, phenelzine, or placebo. Clinical and cognitive evaluations of the patients were under double-blind conditions. Response to treatment did not appear to significantly affect cognitive capacity; neither did treatment with an active substance as compared to placebo. In addition, the baseline level of cognitive functioning did not appear related to whether a patient responded to treatment. The authors conclude that under optimal conditions neither antidepressant produces measurable changes in the cognitive capacity of nondemented elderly patients.