Verbal learning and memory in older adults with minor and major depression

Late-life minor depression (miD) is a prevalent but poorly understood illness. Verbal learning and memory profiles have commonly been used to characterize neuropsychiatric disorders. This study compared the performance of 27 older adults with miD on the California Verbal Learning Test (CVLT) with 26 age-matched individuals with Major Depressive Disorder (MDD) and 36 non-depressed controls. Results revealed that the miD group performed comparably with controls and significantly better than the MDD group on several CVLT indices. Moreover, cluster analysis revealed three distinct groups, consistent with theoretical representations of "normal," "subcortical," and "cortical" verbal learning and memory profiles. The majority of the miD group showed "normal" profiles (74%), whereas most individuals with MDD displayed "subcortical" profiles (54%). The findings suggest that depression in the elderly is a heterogeneous entity and that the CVLT may be a useful tool for characterizing learning and memory in late-onset depressive disorders.