GLUCOSE EFFECTS ON DECLARATIVE AND NONDECLARATIVE MEMORY IN HEALTHY ELDERLY AND YOUNG-ADULTS

Peripheral glucose ingestion enhances performance on explicit declarat ive verbal memory tasks in healthy elderly people. In the present expe riment, healthy young and elderly adults were administered glucose (50 g) or saccharin followed by tests of declarative verbal memory (free recall and recognition of a word list) and a nondeclarative priming te st (word-stem completion). Ln the elderly, glucose significantly enhan ced performance on the declarative but not on the nondeclarative porti ons of the test. Performance by the young subjects was equivalent in t he glucose and saccharin conditions. These findings, that glucose enha nces memory for a declarative/explicit but not nondeclarative/implicit task, sup port the notion that declarative and nondeclarative memory systems are separate functional and anatomic systems.