Evidence map›Paper›PMID 42030358›Full record

ArticlePloS one2026

Sorting the mind: A systematic review and meta-analysis protocol of transcutaneous auricular vagus nerve stimulation on cognitive functions.

Fangqing Liu

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In one paragraph

Article in PloS one, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

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1 · What the graph read from it

What it found

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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

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3 · Its place in the literature

Who cites it

0 citing papers in PubMed.

No citing paper in PubMed yet.

4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

1 author.

Fangqing LiuFaculty of Biology, Medicine and Health, The University of Manchester, Manchester, England, United Kingdom.ORCID https://orcid.org/0009-0008-7913-8964

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

backgroundTranscutaneous auricular vagus nerve stimulation (taVNS) is a non-invasive neuromodulation technique that activates vagal afferents projecting to prefrontal-limbic circuits implicated in attention, memory, and emotion regulation. Preliminary studies suggest that taVNS may enhance cognitive performance; however, the evidence remains fragmented across domains and populations.

objectivesThis systematic review and meta-analysis aim to (1) quantify the overall effects of taVNS on cognitive functions, (2) examine its efficacy across clinical and non-clinical populations, and (3) identify moderators influencing variability in outcomes, including stimulation parameters, participant characteristics, and study design features.

methodsFollowing PRISMA-P guidelines, this protocol will be prospectively registered with PROSPERO. Six databases (PubMed, EMBASE, PsycINFO, Web of Science, CENTRAL, and Scopus) and major trial registries will be systematically searched. Eligible studies include randomised controlled trials assessing validated cognitive outcomes following taVNS compared with sham or active controls. Effect sizes will be calculated as Hedges' g and pooled using random-effects models. Heterogeneity will be evaluated with I² and τ statistics; moderator and meta-regression analyses will explore dose-response and population effects. Risk of bias will be assessed with RoB 2 for randomised trials and ROBINS-I for non-randomised studies, and the certainty of evidence will be rated using GRADE separately by study design. EXPECTED RESULTS AND

conclusionsThis review will provide the first quantitative meta-analytic synthesis of taVNS-induced cognitive modulation across executive, attentional, affective, and learning domains in both clinical and healthy populations, complementing recent narrative syntheses by offering pooled effect size estimates, formal heterogeneity assessment, and a GRADE-rated evidence hierarchy. By delineating domain-specific efficacy and optimal stimulation parameters, the findings aim to inform future clinical applications and the development of standardized neuromodulation protocols.

Indexed as

CognitionTranscutaneous Electric Nerve StimulationVagus Nerve StimulationCognitive EnhancementHumansMeta-Analysis as TopicSystematic Reviews as Topic

Identifiers

PMID42030358
PMCPMC13108857

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the Socratic graph.