Sleep efficiency during the retention period predicts episodic memory reconstruction across young and old adults

Poster Session C - Sunday, March 30, 2025, 5:00 – 7:00 pm EDT, Back Bay Ballroom/Republic Ballroom

Chuu Nyan¹ (chuu.nyan@utexas.edu), Sahana Ram¹, Aiden Wachnin¹, Soroush Mirjalili², Masoud Seraji³, Audrey Duarte¹; ¹Department of Psychology, University of Texas at Austin, ²Department of Psychology, University of Oregon, ³TReNDS Center, Georgia State University & Marcus Autism Center in Emory University

Sleep deprivation studies in young adults suggest that sleep post-encoding is essential for episodic memory consolidation. Habitual sleep quality, and episodic memory, are typically reduced with age, with substantial individual differences, but relatively little is known about the impact of habitual sleep on episodic memory consolidation and supporting neural activity in young or older adults. In the current study, we examined how individual differences in post-encoding sleep quality contribute to episodic memory performance and supporting neural activity in young and old adults. We recorded EEG from cognitively unimpaired younger (n=30) and older (n=29) adults while they retrieved object-scene pairs that either matched or did not match those studied during encoding following a 72-hour, post-encoding, sleep interval. Participants wore a wrist-worn accelerometer for 1 week to measure their habitual sleep, both prior to and following encoding. Memory for object-scene associations, particularly for mismatch pairs, was impaired following the delay in older compared to younger adults, as was retention. A pronounced later posterior negativity (LPN) associated with episodic memory reconstruction was reduced with age, particularly for the mismatch pairs. Moreover, the magnitude of this ERP effect was positively predicted by higher sleep efficiency during the retention period across age groups. Our findings suggest that better sleep efficiency, particularly during the retention period, may facilitate neural mechanisms supporting episodic reconstruction and memory performance that are reduced in older age.

Topic Area: LONG-TERM MEMORY: Episodic