Differential Effects of Non-REM and REM Sleep on Memory Consolidation?
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Sleep benefits memory consolidation. Previous theoretical accounts have proposed a differential role of slow-wave sleep (SWS), rapid-eye-movement (REM) sleep, and stage N2 sleep for different types of memories. For example the dual process hypothesis proposes that SWS is beneficial for declarative memories, whereas REM sleep is important for consolidation of non-declarative, procedural and emotional memories. In fact, numerous recent studies do provide further support for the crucial role of SWS (or non-REM sleep) in declarative memory consolidation. However, recent evidence for the benefit of REM sleep for non-declarative memories is rather scarce. In contrast, several recent studies have related consolidation of procedural memories (and some also emotional memories) to SWS (or non-REM sleep)-dependent consolidation processes. We will review this recent evidence, and propose future research questions to advance our understanding of the role of different sleep stages for memory consolidation.
KeywordsSlow wave sleep Rapid eye movement sleep Declarative memory Non-declarative memory Emotional memory Procedural memory Memory consolidation Reactivation
This work was supported by grants from the Swiss National Foundation (SNF) (PP00P1_133685) and the University of Zürich (Clinical Research Priority Programm "Sleep and Health").
Compliance with Ethics Guidelines
Conflict of Interest
Sandra Ackermann received a grant from the University of Zurich Clinical research priority project “Sleep and Health”.
Björn Rasch received grants from the Swiss National Science Foundation (PP00P1_133685) and from the University of Zurich Clinical research priority project “Sleep and Health”.
Human and Animal Rights and Informed Consent
This article does not contain any studies with human or animal subjects performed by any of the authors.
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