Schedule of Events | Symposia

Linking reactivation during sleep with transformations in neural representations of episodic memory

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

Sarvia Aquino Argueta¹ (ssaquino@uci.edu), Matthew Cho¹, Allison Tran¹, Charli Taylor¹, Fiona Yao¹, Eitan Schechtman¹; ¹University of California, Irvine

Sleep has been shown to play an active role in consolidating memories that are embedded in naturalistic contexts by reactivating their memory traces. Our previous work has shown that selectively targeting memories for reactivation by presenting memory-related sounds during sleep promotes the specificity of episodic memories. The overlap in neural representation among memories that were contextually linked together was reduced when these memories were reactivated, leading to their decontextualization. However, little is known about the impact of endogenous (i.e., non-targeted) memory reactivation has on the links between memories and their contexts. In order to understand how episodic memories are consolidated during sleep, participants formed stories linking four objects of different categories: food, tools, celebrities, and animals. We measured object-context binding using a multivariate pattern analysis with functional MRI (fMRI) before and after sleep, and considered the neural patterns emerging during sleep using both fMRI and EEG. Using fMRI and EEG simultaneously, we monitored reactivation across multiple sleep stages to understand how consolidation plays out over sleep. We hypothesized that reactivation during sleep may lead to further decontextualization. The results of this study inform our understanding of how memory reactivation of objects in their context plays out during undisturbed sleep.

Topic Area: LONG-TERM MEMORY: Episodic