Poster Session A, Saturday, March 23, 1:30 pm - 3:30 pm, Pacific Concourse
Relationship between aerobic capacity and mnemonic discrimination in older adults
Lluvia A. Gonzalez1, Nicole M. Henderson1, Michael S. Ricasa1, Lucy K. Khuu1, Valerie A. Carr1; 1San Jose State University
Numerous studies demonstrate that episodic memory declines with age, yet there is considerable variability in the degree to which individuals experience age-related memory decline. Emerging evidence suggests that differences in cardiorespiratory fitness may contribute to differences in memory performance. Research in aged rodents, for example, demonstrates that aerobic exercise benefits the hippocampus, a region critically important for episodic memory, as well as performance on tasks of hippocampal-dependent memory. In humans, however, the relationship between aerobic capacity and processes supported by the hippocampus, such as pattern separation (the ability to form separable memory representations), remains unclear. Here, we investigated whether individual differences among older adults in aerobic capacity were associated with performance on the Mnemonic Similarity Task (MST), a task that requires mnemonic discrimination. Aerobic capacity was assessed via continuous heart-rate monitoring during the six-minute walk test. Analyses indicated a significant negative correlation between task performance and heart-rate, such that individuals with a lower heart rate (and thus higher aerobic capacity) performed better on the MST than those with a higher heart rate. This relationship held true regardless of task difficulty, defined as degree of similarity between lures and targets. Taken together, these results indicate that variability among older adults in episodic memory, specifically in mnemonic discrimination, is associated with variability in aerobic capacity. These findings will help to inform future intervention-based studies in older adults that aim to slow episodic memory decline.
Topic Area: LONG-TERM MEMORY: Development & aging