Cited by 859Sleep and Wakefulness ResearchMemory and Neural MechanismsNeural dynamics and brain function

Learning-dependent increases in sleep spindle density

Open access
Gais, Steffen, Mölle, Matthias, Helms, Kay, Born, Jan·2002·The Journal of Neuroscience

Abstract

Declarative memory consolidation is enhanced by sleep. In the investigation of underlying mechanisms, mainly rapid eye movement (REM) sleep and slow-wave sleep have been considered. More recently, sleep stage 2 with sleep spindles as a most prominent feature has received increasing attention. Specifically, in rats hippocampal ripples were found to occur in temporal proximity to cortical sleep spindles, indicating an information transfer between the hippocampus and neocortex, which is supposed to underlie the consolidation of declarative memories during sleep. This study in humans looks at the changes in EEG activity during nocturnal sleep after extensive training on a declarative learning task, as compared with a nonlearning control task of equal visual stimulation and subjectively rated cognitive strain. Time spent in each sleep stage, spindle density, and EEG power spectra for 28 electrode locations were determined. During sleep after training, the density of sleep spindles was significantly higher after the learning task as compared with the nonlearning control task. This effect was largest during the first 90 min of sleep (p < 0.01). Additionally, spindle density was correlated to recall performance both before and after sleep (r = 0.56; p < 0.05). Power spectra and time spent in sleep stages did not differ between learning and nonlearning conditions. Results indicate that spindle activity during non-REM sleep is sensitive to previous learning experience.

The claims and statistics of this paper haven’t been checked yet.

Run the check — free, no account needed. It reads the open-access text and checks the sources it cites.

A few free checks a day · papers already verified open instantly · results are public

Integrity signals

Registry

Crossref · 10.1523/jneurosci.22-15-06830.2002

Cites

37 of 37 references verified0 citation errors · 0 not checkable

Statistics

Claims the paper makes

The claims and statistics of this paper haven’t been checked yet.

Run the check — free, no account needed. It reads the open-access text and checks the sources it cites.

A few free checks a day · papers already verified open instantly · results are public

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?

  • Slow oscillations, spindle activity and hippocampal ripple activity are increased during sleep after a learning experience.

    “Also, consistent with this concept, at the level of local field potentials, slow oscillations, spindle activity and hippocampal ripple activity are increased during sleep after a learning experience (Gais, Molle, Helms, & Born 2002; Eschenko, Ramadan, Molle, Born, & Sara 2008; Mölle & Born 2009)”

    From System consolidation of memory during sleep (2012) · cites this paper as Gais, Molle, Helms, & Born 2002

    The Abstract reports higher sleep-spindle density after declarative learning than after a nonlearning control task. It does not report increased slow oscillations or hippocampal ripple activity; the Discussion describes ripple activity in relation to spindles but not a post-learning increase in ripples. The Results report no general difference in EEG power spectra between conditions. (LLM, conf=0.90)

    Experimental — accuracy not yet measured
  • Spindle activity is increased over cortical regions involved in prior learning, positively correlates with post-sleep retrieval performance, and appears to accompany memory reactivations during sleep.

    “Spindle activity is increased over cortical regions involved in prior learning and, moreover, positively correlates with post sleep retrieval performance 180,181 and appears to accompany memory reactivations during sleep.108,114”

    From Sleep—A brain-state serving systems memory consolidation (2023) · cites this paper as [180]

    The Results report increased spindle density after learning, greatest at the frontal Fz electrode, and a positive correlation with recall performance after sleep. Neither the Results nor Discussion establishes that the increase occurred over cortical regions involved in the prior learning task. The separate citations 108 and 114 attach to the memory-reactivation clause, so that clause is not attributed to this source. (LLM, conf=0.86)

    Experimental — accuracy not yet measured
  • Intense learning of declarative memories (word pairs or virtual maze) increases the number of spindles (12-15 Hz) during subsequent sleep, particularly in the early part of the night.

    “Intense learning of declarative memories (word pairs or virtual maze) increases the number of spindles (12-15 Hz) during subsequent sleep, particularly in the early part of the night (432, 812).”

    From About Sleep's Role in Memory (2013) · cites this paper as [432]

    The Subjects and procedures section describes 60 minutes of learning word pairs, and the Abstract reports higher spindle density during subsequent sleep, with the largest effect in the first 90 minutes. The Discussion identifies 12–15 Hz as the spindle frequency band. This paper does not report a virtual-maze learning task, so that part of the sentence is not supported by this source. (LLM, conf=0.86)

    Experimental — accuracy not yet measured

Self-check

Percentages, sums and reported differences re-computed from the paper’s own numbers.

The self-check needs the paper’s full text.

Cites

Flagged first, then by citations

Cited by

Sorted by citations

Authors
Gais, S., Mölle, M., Helms, K., & Born, J.
Affiliations
University of Lübeck (DE)
Venue
The Journal of Neuroscience
Published
2002-08-01
Volume
22
Issue
15
Pages
6830-6834
ISSN
  • 0270-6474 (ISSN-L)
  • 1529-2401
OpenAlex
W1803658430
Cited by
859
References
37
Citations by year
2026: 18 · 2025: 33 · 2024: 40 · 2023: 45 · 2022: 38 · 2021: 31 · 2020: 48 · 2019: 49 · 2018: 38 · 2017: 47 · 2016: 40 · 2015: 45 · 2014: 46 · 2013: 50 · 2012: 43
FWCI
6.70
Type
journal article
Language
en
Open access
Locations
  • Journal of Neuroscience (publishedVersion)
  • PubMed Central (publishedVersion)
  • PubMed (publishedVersion)
Funders
Deutsche Forschungsgemeinschaft
Topics
  • Life Sciences › Neuroscience › Cognitive Neuroscience › Sleep and Wakefulness Research
  • Life Sciences › Neuroscience › Cognitive Neuroscience › Memory and Neural Mechanisms
  • Life Sciences › Neuroscience › Cognitive Neuroscience › Neural dynamics and brain function
Keywords
sleep spindles, sleep spindle density, declarative memory consolidation, NREM sleep, stage 2 sleep, EEG power spectra, memory retrieval, cognitive strain, nocturnal sleep
MeSH terms
Adolescent, Adult, Cognition, Electroencephalography, Female, Hippocampus, Humans, Learning, Male, Memory, Photic Stimulation, Sleep, Sleep Stages, Sleep, REM

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