MEMORY PROCESSES IN DEPRESSED GERIATRIC-PATIENTS WITH AND WITHOUT SUBCORTICAL HYPERINTENSITIES ON MRI

In this study, 12 patients over age 60 with depression with moderate t o severe subcortical hyperintensities (SH) localized to the periventri cular white matter were identified by quantitative MRI. Using the Cali fornia Verbal Learning Teal, they were compared with 12 age-, educatio n-, and severity-matched patients with depression with minimal white m atter changes on specific aspects of memory performance. Patients with cortical lesions, neurologic or systemic illness affecting cognition, and history of substance abuse were excluded. Patients in the group w ith high SH showed reduced use of semantic encoding strategies (p < 0. 05), reduced learning efficiency (p < 0.05), and a greater discrepancy between free recall and recognition discriminability (p < 0.05) than their low SH counterparts. This pattern of performance on memory tasks is similar to that found in previous studies to be associated with su bcortical degenerative disorders such as Huntington's and Parkinson's diseases. Geriatric patients with depression with SH may represent a s ubgroup with greater subcortical involvement, with associated cognitiv e and functional decline.