Effect of Glucose and Peripheral Glucose Regulation on Memory in the Elderly

We examined changes in cognitive performance following the intake of a glucose (50 g) or saccharin solution (50 mg) in fasted elderly male and female subjects. Glucoregulation was estimated using a recovery index that was used to categorize subjects within each sex as having poor or good recovery. Elderly males with poor recovery performed worse on the Logical Memory subtest of the Wechsler Memory Scale and on the free recall or recognition parts of a work list task. The item analysis of the Logical Memory subtest showed that male subjects with poor recovery remembered less of the last items of the paragraphs after drinking saccharin while the first items were equally remembered by both groups. Glucose improved the performance of the males with good regulation for the first seven items while the performance of males with poor regulation decreased for those items under glucose. The present study support the notion that peripheral glucoregulation can influence memory performance and that the ingestion of glucose can influence certain aspects of memory functioning.