Sleep and Rehearsal-Driven Memory in Epilepsy

Memory consolidation transforms unstable memory traces into lasting representations, a process enhanced by both sleep and rehearsal during learning. Rehearsal is thought to accelerate consolidation by inducing memory reactivations that resemble those occurring during sleep. However, the respective mechanisms of sleep- and rehearsal-induced consolidation-and their potential interactions-remain poorly understood, especially in patients with temporal lobe epilepsy, where rehearsal might help compensate for memory deficits linked to hippocampal dysfunction, and where sleep may exacerbate epileptic activity. The CORESOM-EPI study aims to compare the effects of rehearsal and sleep on memory consolidation in patients undergoing video-EEG monitoring. Participants will learn "object-place" associations under two conditions (single versus repeated encoding), with memory tested immediately and again after a 12-hour delay. This delay will either include a full day awake or a night of sleep, allowing direct comparison of sleep- and rehearsal-related consolidation effects. Each participant will perform the task twice, with "wake" and "sleep" condition, in a balanced order. As a preliminary phase of the CRIMES study (ANR-DFG 2024), CORESOM-EPI will help assess how sleep and rehearsal influence memory consolidation in epilepsy. It will also serve to adapt the behavioral task for clinical use, paving the way for a future intracranial EEG investigations that will explore the neural networks involved and their modulation by epileptic activity.