NCT05801809

Understanding the Effects of Transauricular Vagus Nerve Stimulation on Neural Networks and Autonomic Nervous System

Active, enrolled NA Results posted Last updated 10 December 2025

What this trial tests

NA trial testing Transauricular vagus nerve stimulation (taVNS) in Healthy Volunteers in 44 participants. Participants enrolled and being followed up; not accepting new ones.

Timeline

26 April 2023

Primary endpoint
23 September 2023

1 March 2026

Quick facts

Lead sponsor	Spaulding Rehabilitation Hospital
Phase	NA
Status	Active, enrolled
Study type	INTERVENTIONAL
Allocation	randomized
Design	parallel
Masking	triple
Primary purpose	other
Enrollment	44
Start date	26 April 2023
Primary completion	23 September 2023
Estimated completion	1 March 2026
Sites	1 location across United States

Drugs / interventions tested

• Transauricular vagus nerve stimulation (taVNS)

Conditions studied

• Healthy Volunteers — all drugs for Healthy Volunteers →

Sponsor

Spaulding Rehabilitation Hospital

Who can join

Adults 18 to 99, any sex, with Healthy Volunteers. Patients with the condition only — healthy volunteers not accepted.

Results — posted to ClinicalTrials.gov

Per-arm endpoint measurements with 95% confidence intervals where reported. Source: trial results section.

Resting-state Electroencephalogram (EEG) Primary · Change from baseline to 60 minutes post-intervention.

Resting-state EEG was recorded using a 64-channel high-density EGI system (Electrical Geodesics, Inc., Eugene, USA) under the eyes closed condition. Data was filtered into standard frequency bands using short-time Fourier transformation (STFT): delta (0.5-4 Hz), theta (4-8 Hz), alpha (8-13 Hz), beta (13-30 Hz), and gamma (30-80 Hz). Frontal asymmetry was computed as the difference in power between homologous left and right frontal electrodes (e.g., F3-F4) in the alpha band.

Group	Value	95% CI
Active taVNS	0.016	± 0.012
Sham taVNS	-0.025	± 0.016

Conditioned Pain Modulation (CPM) Response - Change in Pain Ratings on the Pain-6 Scale (0-10) Primary · Change from baseline to 60 minutes post-taVNS.

Pain intensity was measured using the Numeric Pain Scale (NPS; 0 = no pain, 10 = worst pain). Higher scores indicate worse pain. A "pain-6 temperature" was first identified (temperature that elicits NPS = 6). Test stimulus: Pain-6 temperature applied for 30s; participants rated pain at 10, 20, and 30s. The test-stimulus score is the average of the three NPS ratings. Conditioned stimulus: After 5 minutes, the left hand was immersed in 10-12°C water for 30s while the same pain-6 temperature was applied again. Pain was rated the same way, and the conditioned-stimulus score is the average of the

Group	Value	95% CI
Active taVNS	0.34	± 0.60
Sham taVNS	-0.53	± 1.14

Heart Rate Variability (HRV) Secondary · Post-intervention (after 60 minutes of taVNS)

HRV from ECG on non-dominant hand. High-frequency HRV calculated from 5-min resting recordings; higher values indicate greater parasympathetic activity. Post-stimulation values (60 min) were analyzed.

Group	Value	95% CI
Active taVNS	0.6	± 0.3
Sham taVNS	0.1	± 0.2

Adverse events — posted to ClinicalTrials.gov

Time frame: Side effects were assessed on the same day, immediately after the stimulation.. Reporting threshold: 0%. Adverse-event reports describe events observed during the trial — not all are caused by the drug.

Active taVNS

Serious: 0/22 (0%)

Deaths: 0/22

Sham taVNS

Serious: 0/22 (0%)

Deaths: 0/22

Other adverse events (1 terms — click to expand)

Reaction	System	Active taVNS	Sham taVNS
Expected side effect	Ear and labyrinth disorders	—	—

Data from ClinicalTrials.gov NCT05801809 adverse events section.

Sponsor's own description

This trial aims to perform an exploratory, mechanistic, randomized double-blind sham-control trial in healthy participants to assess the physiologic effects of a single 60 minutes session of bilateral taVNS, on neural networks and autonomic function.

Publications & conference data

3 peer-reviewed publications reference this trial (live from Europe PMC):

1. Age as an Effect Modifier of the Effects of Transcutaneous Auricular Vagus Nerve Stimulation (taVNS) on Heart Rate Variability in Healthy Subjects.
   Gianlorenço AC, Pacheco-Barrios K, Daibes M, Camargo L, et al · · 2024 · cited 9× · PMID 39064307 · DOI 10.3390/jcm13144267
2. Transauricular Vagus Nerve Stimulation (taVNS) enhances Conditioned Pain Modulation (CPM) in healthy subjects: A randomized controlled trial.
   Pacheco-Barrios K, Gianlorenco AC, Camargo L, Andrade MF, et al · · 2024 · cited 8× · PMID 38453004 · DOI 10.1016/j.brs.2024.03.006
3. The effects of non-invasive transcutaneous auricular vagus nerve stimulation on resting-state delta oscillation: a randomized, double-blinded, sham-control trial.
   Camargo L, Gianlorenço AC, Pacheco-Barrios K, Pichardo E, et al · · 2025 · cited 1× · PMID 41044114 · DOI 10.1038/s41598-025-17821-5