Effects of depression and ECT on anterograde memory.

This study investigated immediate and delayed recognition memory in depressed patients undergoing electroconvulsive therapy (ECT) and in matched, normal controls. At baseline, patients manifested a marked deficit in immediate memory (acquisition), but showed no deficit in delayed memory (retention). When retested 24-36 hr following the seventh ECT, patients showed reductions in both immediate and delayed memory performance. At retesting 4 days, on average, after the ECT course, immediate memory scores returned to baseline levels, but delayed memory performance remained impaired. The findings supported the classic claims that depression is associated with a deficit in the acquisition of information, whereas ECT has a more profound influence on the retention of information. This dissociative pattern could not be viewed as an artifact of task psychometric properties, nor of practice effects in control subjects.