Dreaming and Offline Memory Consolidation
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Converging evidence suggests that dreaming is influenced by the consolidation of memory during sleep. Following encoding, recently formed memory traces are gradually stabilized and reorganized into a more permanent form of long-term storage. Sleep provides an optimal neurophysiological state to facilitate this process, allowing memory networks to be repeatedly reactivated in the absence of new sensory input. The process of memory reactivation and consolidation in the sleeping brain appears to influence conscious experience during sleep, contributing to dream content recalled on awakening. This article outlines several lines of evidence in support of this hypothesis, and responds to some common objections.
KeywordsSleep Dreaming Rapid eye movement Non-rapid eye movement Memory consolidation Offline processing Memory reactivation Replay Consciousness
Compliance with Ethics Guidelines
Conflict of Interest
Erin J. Wamsley declares that the research described here was supported by National Institute of Mental Health grant R01-MH48832 (principal investigator Robert Stickgold), National Institutes of Health T32 training grant HL07901-10 to the Harvard Division of Sleep Medicine, and a KL2 Medical Research Investigator Training award (an appointed KL2 award) from Harvard Catalyst | The Harvard Clinical and Translational Science Center (National Center for Research Resources and the National Center for Advancing Translational Sciences, National Institutes of Health award 8KL2TR000168-05). She is also a principal investigator supported by an R21 grant from the National Institute of Mental Health (1R21MH098171-01A1) and has received grants from the BIAL Foundation. She has also received compensation for teaching a course at Harvard University.
Human and Animal Rights and Informed Consent
This article does not report original research findings. Some studies described here were performed in our laboratory at Beth Israel Deaconess Medical Center, where all human subjects signed informed consent prior to participation.
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