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Heilberg, J.

Publications and source records attributed to Heilberg, J..

2 recordsLinked to original sources

Context matters: Changes in memory over a period of sleep are driven by encoding context

During sleep, recently acquired episodic memories (i.e., autobiographical memories for specific events) are strengthened and transformed, a process termed consolidation. These memories are contextual in nature, with details of specific features interwoven with more general properties such as the time and place of the event. In this study, we hypothesized that the context in which a memory is embedded would guide the process of consolidation during sleep. To test this idea, we employed a spatial memory task and considered changes in memory over a 10-hour period including either sleep or wake. In both conditions, participants (N = 62) formed stories that contextually bound four objects together, and then encoded the on-screen spatial position of all objects. Results showed that the changes in memory over the sleep period were correlated among contextually linked objects, whereas no such effect was identified for the wake group. These results suggest that contexts binding different memories together play an active role in consolidation during sleep.

neuroscience↗

Made together, replayed together: Context reinstatement during sleep guides memory consolidation

New memories arent quarantined from each other when first encoded; rather, they are interlinked with memories that were encoded in temporal proximity or share semantic features. By selectively biasing memory processing during sleep, here we test whether context influences sleep-consolidation. Participants first formed 18 idiosyncratic narratives, each linking four objects together. Before sleep,they also memorized an on-screen position for each object. During sleep, 12 object-specific sounds were unobtrusively presented, thereby cuing the corresponding spatial memories and impacting spatial recall as a function of initial memory strength. As hypothesized, we find that recall for non-cued objects contextually linked with cued objects also changed. Post-cue electrophysiological responses suggest that activity in the sigma band supports context reinstatement and predicts context-related memory benefits. Concurrently, context-specific electrophysiological activity patterns emerge during sleep. We conclude that reactivation of individual memories during sleep evokes reinstatement of their context, thereby impacting consolidation of associated knowledge.

neuroscience↗