
14 Mar Exercising for Memory Retention
Excessive sedentary behaviour is highly prevalent amongst the elderly population and is known to contribute to physical and mental health risks. Aging is additionally seen to affect our sleep patterns and behaviours, with more fragmented sleep occurring as well as less time being spent in deeper sleep stages. While moderate physical activity is well known to be associated with better mental health, executive function, and self-regulation, recent work has been done to explore the benefits of this type of activity with the consolidation of memories.
Memory formation has been seen to be better helped by sleep periods compared to wakefulness. Specifically, the REM (Rapid eye movement) sleep stage is agreed to play a crucial role in the formation of emotional memories (Wagner, 2001). Further, we understand that memory holding emotional content is better remembered by individuals than those of neutral emotion. Memory quality can be measured through mnemonic discrimination, which is a behavioural assessment for hippocampal pattern separation, a process which facilitates the storage of similar experiences as unique memory traces.
While recognition memory for neutral events is preserved through aging, older adults do show worse emotional (negative and positive) memory recognition after a 24-hr period of consolidation, as well as no consolidation benefit for emotional mnemonic discrimination. Therefore, an assessment of the effect physical activity has on bolstering consolidation for emotional recognition memory and mnemonic discrimination in older adults has been performed. It has been shown that by substituting even short durations of low-intensity activity for moderate-intensity physical activity one could produce significant cognitive and memory gains in older adulthood.
While these findings were specific to memories containing negative emotional content, they do provide evidence that the reallocation of physical activities yields a memory consolidation benefit in older adults. In a population where the risks of cognitive decline are higher, targeted interventions and changes in behaviour aimed at promoting memory preservation in older adults should include this substitution of more sedentary behaviours with moderate physical activity, even for short durations.
References
Chappel-Farley, M.G., Berisha, D.E., Dave, A. et al. Engagement in moderate-intensity physical activity supports overnight memory retention in older adults. Sci Rep 14, 31873 (2024). https://doi.org/10.1038/s41598-024-83336-0
Wagner U, Gais S, Born J. Emotional memory formation is enhanced across sleep intervals with high amounts of rapid eye movement sleep. Learn Mem. 2001 Mar-Apr;8(2):112-9. Doi: 10.1101/lm.36801.