Verbal memory in mania: effects of clinical state and task requirements

Objectives: Manic patients exhibit impaired verbal learning and memory, particularly following longstanding illness. However, it is unclear whether recognition and recall performance are differentially influenced by a manic mood state. Methods: To examine this issue, we administered the California Verbal Learning Test and symptom-rating scales to inpatients with pure or mixed mania, euthymic outpatients, and healthy comparison subjects. Results: An overall performance difference was identified between groups. Manic and euthymic patients performed more poorly than healthy subjects on recall. However, manic patients performed more poorly than euthymic patients and healthy subjects on recognition. Conclusions: These results suggest that verbal retrieval deficits are stable vulnerability indicators in bipolar disorder, whereas verbal encoding deficits are manic episode indicators. The known subcortical dysfunction in this disorder may produce stable retrieval deficits while acute mood symptoms attenuate encoding during affective episodes only.