Cited by 208Neural dynamics and brain functionSleep and Wakefulness ResearchMemory and Neural Mechanisms

Slow oscillation electrical brain stimulation during waking promotes EEG theta activity and memory encoding

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Kirov, Roumen, Weiss, Carsten, Siebner, Hartwig R., Born, Jan, Marshall, Lisa·2009·Proceedings of the National Academy of Sciences

Abstract

The application of transcranial slow oscillation stimulation (tSOS; 0.75 Hz) was previously shown to enhance widespread endogenous EEG slow oscillatory activity when applied during a sleep period characterized by emerging endogenous slow oscillatory activity. Processes of memory consolidation typically occurring during this state of sleep were also enhanced. Here, we show that the same tSOS applied in the waking brain also induced an increase in endogenous EEG slow oscillations (0.4-1.2 Hz), although in a topographically restricted fashion. Applied during wakefulness tSOS, additionally, resulted in a marked and widespread increase in EEG theta (4-8 Hz) activity. During wake, tSOS did not enhance consolidation of memories when applied after learning, but improved encoding of hippocampus-dependent memories when applied during learning. We conclude that the EEG frequency and related memory processes induced by tSOS critically depend on brain state. In response to tSOS during wakefulness the brain transposes stimulation by responding preferentially with theta oscillations and facilitated encoding.

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Crossref · 10.1073/pnas.0904438106

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  • Theta rhythm substantially correlates with episodic and emotional memory in waking EEG studies.

    “waking EEG studies showing that the theta rhythm substantially correlates with episodic and emotional memory”

    From The Functional Role of Dreaming in Emotional Processes (2019) · cites this paper as Kirov et al., 2009

    The Discussion (page unavailable) reports that waking EEG theta activity is associated with episodic-memory encoding and retrieval. It does not report a corresponding relationship with emotional memory, so that part of the claim is unsupported. (LLM, conf=0.87)

    Experimental — accuracy not yet measured
  • Effects of SO-tDCS depend on brain state: when applied during waking (rather than during non-REM sleep), tDCS induced a widespread increase in 4-8 Hz theta and 16-14 Hz beta activity, rather than slow oscillation activity, and these increases were associated with an enhanced encoding of declarative memory (for words), particularly in later learning trials (R5, R6), whereas consolidation across the

    “D: effects of SO-tDCS depend on brain state: when applied during waking (rather than during non-REM sleep), tDCS induced a widespread increase in 4 -8 Hz theta and 16 -14 Hz beta activity, rather than slow oscillation activity, and these increases were associated with an enhanced encoding of declarative memory (for words), particularly in later learning trials (R5, R6), whereas consolidation”

    From About Sleep's Role in Memory (2013) · cites this paper as [643]

    Split into 2 atoms — 1 confirmed, 1 partially supported, 0 disputed, 0 misattributed, 0 unverifiable. Expand the claim to see per-atom verdicts.

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  • Applying the 0.75 Hz slow oscillatory stimulation during wakefulness induced a widespread increase in theta (4-8 Hz), rather than slow oscillation activity, and this increase in theta activity was associated with a significant improvement in the encoding of declarative memories, rather than affecting retention of these memories.

    “Applying the 0.75 Hz slow oscillatory stimulation during wakefulness induced a widespread increase in theta (4 -8 Hz), rather than slow oscillation activity, and this increase in theta activity was associated with a significant improvement in the encoding of declarative memories, rather than affecting retention of these memories (FIGURE 5D, Ref. 643).”

    From About Sleep's Role in Memory (2013) · cites this paper as [643]

  • toDCS only at 0.75 Hz (not at 5 Hz) and applied only during sleep leads to an increase of memory consolidation.

    “In addition, there is evidence that toDCS only at 0.75 Hz (not at 5 Hz) and applied only during sleep leads to an increase of memory consolidation [32,52,53].”

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Research works printed but not linked: 2

  1. [56]Janke W, Debus G. Die Eigenschaftswörterliste EWL. Eine mehrdimensionale Methode zur Beschreibung von Aspekten des Befindens. Göttingen, Germany: Hogrefe; 1978. [Google Scholar]
  2. [57]Aschenbrenner S, Tucha KW, Lange W. Regensburg Word Fluency Test. Göttingen, Germany: Hogrefe; 2000. in German. [Google Scholar]

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Authors
Kirov, R., Weiss, C., Siebner, H. R., Born, J., & Marshall, L.
Affiliations
  • Bulgarian Academy of Sciences (BG)
  • University of Lübeck (DE)
  • Copenhagen University Hospital (DK)
  • Department of Neuroendocrinology, University of Lübeck, 23538 Lübeck, Germany;
Corresponding author
Marshall, Lisa
Venue
Proceedings of the National Academy of Sciences
Published
2009-09-08
Volume
106
Issue
36
Pages
15460-15465
ISSN
  • 0027-8424 (ISSN-L)
  • 1091-6490
OpenAlex
W2008440125
Cited by
208
References
58
Citations by year
2026: 4 · 2025: 7 · 2024: 5 · 2023: 4 · 2022: 15 · 2021: 14 · 2020: 6 · 2019: 17 · 2018: 16 · 2017: 10 · 2016: 18 · 2015: 12 · 2014: 20 · 2013: 18 · 2012: 16
FWCI
6.80
Type
journal article
Language
en
Open access
Locations
  • Proceedings of the National Academy of Sciences (publishedVersion)
  • PubMed Central (publishedVersion)
  • PubMed (publishedVersion)
  • Research at the University of Copenhagen (University of Copenhagen) (submittedVersion)
Funders
Deutsche Forschungsgemeinschaft
Topics
  • Life Sciences › Neuroscience › Cognitive Neuroscience › Neural dynamics and brain function
  • Life Sciences › Neuroscience › Cognitive Neuroscience › Sleep and Wakefulness Research
  • Life Sciences › Neuroscience › Cognitive Neuroscience › Memory and Neural Mechanisms
Keywords
transcranial electrical stimulation, theta oscillations, memory encoding, memory consolidation, hippocampal-dependent memory, wakefulness
MeSH terms
Adult, Analysis of Variance, Brain, Electric Stimulation Therapy, Germany, Humans, Learning, Memory, Oscillometry, Theta Rhythm, Wakefulness

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