Schedule of Events | Symposia

Episodic simulation samples from recently encoded memories

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

Tongle Cai¹ (tonglec@uoregon.edu), Zhifang Ye¹, Katie L. Hedman¹, Alexandra G. Tremblay-McGaw¹, Sara DuBrow¹, Robert J. Molitor¹, Brice A. Kuhl¹; ¹University of Oregon

Episodic memory is crucial for both remembering the past and simulating novel or future events. Recent neuroimaging studies emphasize the constructive nature of memory retrieval and suggest that remembering the past and simulating novel events engage similar neural processes. Yet, it is not entirely clear how the brain incorporates the contents of existing memories into simulated events. Here, we used fMRI pattern similarity analyses to compare neural representations of retrieved and simulated events. Participants (n=33) were scanned while watching short video clips, remembering previously viewed videos, and simulating novel events that were conceptually related to the content of watched and remembered videos. Critically, we manipulated the order of these tasks such that sometimes simulation was performed before watching or remembering related events (thereby preventing sampling from recent experience), whereas other times simulation following watching or remembering related events (thereby enabling sampling). Within regions of the episodic memory network, pattern similarity between conceptually-related simulation and retrieval trials was significantly stronger when simulation followed related experience than when simulation preceded related experience, suggesting that simulation sampled from recent, relevant experience. This finding was reinforced by verbal descriptions of simulated events that were collected after scanning. Importantly, similarity between simulated and remembered events was absent in visual cortical areas, highlighting a unique role of the episodic memory network in reflecting episodic sampling during event simulation. Collectively, these findings contribute to understanding of how the brain incorporates past experience when simulating new experience.

Topic Area: LONG-TERM MEMORY: Episodic