The role of daytime napping in declarative memory performance: a systematic review
Abstract
Sleep plays an important role in stabilizing and reinforcing memory of newly acquired information. Like nocturnal sleep, a daytime nap is shown to effectively contribute to memory processing. However, studies are often focused on nocturnal sleep. This review has aimed at systematically compiling the results of studies which have examined the effects of napping on declarative memory performance in healthy adults. Such studies have focused on different aspects of memory reinforcement following a diurnal nap including the involved mechanisms in memory reconsolidation, type of declarative tasks, cross-gender differences, the role of age, duration of nap and its delayed onset. One of the reviewed studies reported that even as short as 6 min of napping exerts a positive effect on memory function. Evidence from these studies indicates hippocampal-dependent enhancement of the learned information. Diurnal naps predominantly include non-rapid eye movement sleep with slow waves yielding potential effects on declarative memory. Evidence has shown that the empowered learning and retrieval depends upon spindle density during the nap. Moreover, the role of coordinated autonomic and central events in enhancing declarative memory has also been reported. Slow waves and sleep spindles are known to fuel declarative memory function during the NREM-2 (N2) stage of sleep.
Integrity signals
Registry
Cites
Statistics
Claims the paper makes
Claims other papers make about this one
Each is checked against this paper’s own text: does it say what the citing paper says it does?
Continued acute sleep deprivation can have varying effects on memory functions, potentially dependent on the cognitive load of tasks.
“Continued acute sleep deprivation can have varying effects on memory functions, potentially dependent on the cognitive load of tasks [18].”
From Sleep and memory consolidation in healthy, neurotypical children, and adults: a summary of systematic reviews and meta-analyses. (2023) · cites this paper as [18]
These benefits are particularly pronounced for naps taken earlier in the afternoon, with even brief naps of ∼6min shown to bolster declarative memory consolidation through sleep-specific mechanisms such as sleep spindles and slow-wave activity.
“These benefits are particularly pronounced for naps taken earlier in the afternoon, with even brief naps of ∼6min shown to bolster declarative memory consolidation through sleep-specific mechanisms such as sleep spindles and slow-wave activity [18].”
From Sleep and memory consolidation in healthy, neurotypical children, and adults: a summary of systematic reviews and meta-analyses. (2023) · cites this paper as [18]
Daytime napping provides cognitive benefits, enhancing alertness, reaction time, and memory retrieval.
“However, daytime napping has been documented to provide cognitive benefits, enhancing alertness, reaction time, and memory retrieval, as evidenced by a synthesis of findings from experimental studies [17,18].”
From Sleep and memory consolidation in healthy, neurotypical children, and adults: a summary of systematic reviews and meta-analyses. (2023) · cites this paper as [18]
Meta-analyses, such as Schäfer et al. [18], do not consistently support preferential consolidation of emotional over neutral memories.
“Some studies demonstrate emotional memory benefits, but meta-analyses, such as Schäfer et al. [18], do not consistently support preferential consolidation of emotional over neutral memories.”
From Sleep and memory consolidation in healthy, neurotypical children, and adults: a summary of systematic reviews and meta-analyses. (2023) · cites this paper as [18]
Cites
Connections between sleep and cognition in older adults
Yaffe, K., Falvey, C. M., & Hoang, T. (2014) · The Lancet Neurology · doi:10.1016/s1474-4422(14)70172-3 · Cited by 796 · see citing works
The contribution of sleep to hippocampus-dependent memory consolidation
Marshall, L., & Born, J. (2007) · Trends in Cognitive Sciences · doi:10.1016/j.tics.2007.09.001 · Cited by 667 · see citing works
Sleep-dependent learning: A nap is as good as a night
Mednick, S., Nakayama, K., & Stickgold, R. (2003) · Nature Neuroscience · doi:10.1038/nn1078 · Cited by 594 · see citing works
Daytime naps, motor memory consolidation and regionally specific sleep spindles
Nishida, M., & Walker, M. P. (2007) · PLoS ONE · doi:10.1371/journal.pone.0000341 · Cited by 531 · see citing works
Sleep after learning aids memory recall
Gais, S., Lucas, B., & Born, J. (2006) · Learning & Memory · doi:10.1101/lm.132106 · Cited by 457 · see citing works
A role for REM sleep in recalibrating the sensitivity of the human brain to specific emotions
Gujar, N., McDonald, S. A., Nishida, M., & Walker, M. P. (2011) · Cerebral Cortex · doi:10.1093/cercor/bhq064 · Cited by 276 · see citing works
Dreaming of a learning task is associated with enhanced sleep-dependent memory consolidation
Wamsley, E. J., Tucker, M., Payne, J. D., Benavides, J. A., & Stickgold, R. (2010) · Current Biology · doi:10.1016/j.cub.2010.03.027 · Cited by 255 · see citing works
Involvement of spindles in memory consolidation is slow wave sleep-specific
Cox, R., Hofman, W. F., & Talamini, L. M. (2012) · Learning & Memory · doi:10.1101/lm.026252.112 · Cited by 163 · see citing works
Sleep-Dependent Facilitation of Episodic Memory Details
van der Helm, E., Gujar, N., Nishida, M., & Walker, M. P. (2011) · PLoS ONE · doi:10.1371/journal.pone.0027421 · Cited by 138 · see citing works
Wamsley, E. J., Tucker, M. A., Payne, J. D., & Stickgold, R. (2010) · Learning & Memory · doi:10.1101/lm.1828310 · Cited by 89 · see citing works
Sleep stage II contributes to the consolidation of declarative memories
Ruch, S., Markes, O., Duss, S. B., Oppliger, D., Reber, T. P., Koenig, T., Mathis, J., Roth, C., & Henke, K. (2012) · Neuropsychologia · doi:10.1016/j.neuropsychologia.2012.06.008 · Cited by 88 · see citing works
Relational Memory: A Daytime Nap Facilitates the Abstraction of General Concepts
Lau, H., Alger, S. E., & Fishbein, W. (2011) · PLoS ONE · doi:10.1371/journal.pone.0027139 · Cited by 75 · see citing works
Debarnot, U., Castellani, E., Guillot, A., Giannotti, V., Dimarco, M., & Sebastiani, L. (2012) · Neurobiology of Learning and Memory · doi:10.1016/j.nlm.2012.10.009 · Cited by 17 · see citing works
Flagged first, then by citations
Cited by
Sorted by citations
The role of sleep for episodic memory consolidation: stabilizing or rescuing?
Zhang, J., Whitehurst, L. N., & Mednick, S. C. (2022) · Neurobiology of Learning and Memory · doi:10.1016/j.nlm.2022.107621 · Cited by 34 · see citing works
Weighall, A., & Kellar, I. (2023) · Emerging Topics in Life Sciences · doi:10.1042/etls20230110 · Cited by 13 · see citing works
- Authors
- Farhadian, N., Khazaie, H., Nami, M., & Khazaie, S.
- Affiliations
- Kermanshah University of Medical Sciences (IR)
- Shiraz University of Medical Sciences (IR)
- Corresponding author
- Khazaie, Habibolah
- Khazaie, Sepideh
- Venue
- Sleep Medicine
- Publisher
- Elsevier BV
- Published
- 2021-08
- Volume
- 84
- Pages
- 134-141
- ISSN
- 1389-9457 (ISSN-L)
- OpenAlex
- W3169667745
- Cited by
- 28
- References
- 13
- Citations by year
- 2026: 5 · 2025: 7 · 2024: 6 · 2023: 5 · 2022: 5
- FWCI
- 0.59
- Type
- journal article
- Language
- en
- Open access
- closed
- Licence
- Locations
- Sleep Medicine (publishedVersion)
- PubMed (publishedVersion)
- Funders
- Kermanshah University of Medical Sciences Vice Chancellor for Research and Technology
- Kermanshah University of Medical Sciences
- Topics
- Life Sciences › Neuroscience › Cognitive Neuroscience › Sleep and Wakefulness Research
- Life Sciences › Neuroscience › Cognitive Neuroscience › Memory and Neural Mechanisms
- Social Sciences › Psychology › Experimental and Cognitive Psychology › Sleep and related disorders
- Keywords
- daytime napping, declarative memory, memory consolidation, memory reconsolidation, slow waves, sleep spindles, hippocampal-dependent memory, nap duration, gender differences, age effects
- MeSH terms
- Cognition, Hippocampus, Humans, Learning, Memory, Sleep
About these checks
Registry, retraction, Cites and statistics results are computed, not judged, with one exception: a printed reference that no index lists is read once by a model before it counts as a citation error. Claims are extracted by a model and kept only when their quote appears verbatim in the text; each cited source is then checked, with a model’s help, for whether it says what the claim relies on. Those verdicts can be wrong — read the claim’s quote and the cited source before relying on one.
Statistics and arithmetic are recomputed, not judged.
Confidence bands are shown only for fields calibrated on our annotated test set. None is calibrated yet, so no band is shown.
What counts as a claim ›How we measure confidence ›How we check this ›
Are you an author, or do you see a problem with this page? Request a review
