40 Hz Transcutaneous Auricular Vagus Nerve Stimulation Enhances Verbal Free Recall in Healthy Adults by Modulating Frontal Theta Oscillations.

Healthy adults who received 40-Hz ear-based vagus nerve stimulation recalled more words than the other groups, alongside a temporary increase in frontal theta activity. This does not establish benefit for memory disorders.

Luo Y, Yin S, Chen L, Gao H, Zhao P, Wen H.
NeuroImage · Publication date: 2026-10-02
Added to site: 2026-10-03
DOI: 10.1016/j.neuroimage.2026.122273

Publication date verified in PubMed. This source date is separate from the site's addition date.

Modalities

taVNS, EEG, Neuromodulation

Clinical focus

Verbal free recall, Frontal theta, Frequency-specific stimulation

Population

Healthy young adults

Sample

44 participants total; allocation counts for sham, 20-Hz and 40-Hz groups were not provided in the checked abstract

Intervention / method

Free recall was assessed before and after sham, 20-Hz or 40-Hz transcutaneous auricular vagus nerve stimulation, with resting EEG recorded at baseline and multiple post-stimulation time points

Comparator

40-Hz taVNS versus 20-Hz taVNS and sham stimulation

Clinician summary

The 40-Hz group showed better free recall than sham and 20-Hz groups, with an immediate frontal-theta increase that declined over time. Theta measures correlated with recall, and an exploratory Bayesian mediation analysis supported a theta-dependent model.

How to interpret the findings

The sample was small, single-blind and limited to healthy young adults. The abstract does not provide arm denominators, effect sizes, confidence intervals, stimulation dose, adverse-event results or the duration of behavioral benefit. The mediation analysis was exploratory.

Equipment and disclosures

A transcutaneous auricular vagus nerve stimulation setup and resting EEG were used. The checked abstract does not identify devices, electrode placement details or manufacturers.

The authors declared no competing financial interests or personal relationships. Funding details were not exposed in the checked abstract or Crossref record.

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