Transcutaneous Vagus Nerve Stimulation (tVNS) and Stress Regulation During Performance Tasks

This study examines how individuals respond to performance-related tasks and whether a non-invasive ear stimulation device influences stress responses during those tasks. Participants will be randomly assigned to use either an active or inactive (placebo) version of a transcutaneous vagus nerve stimulation (tVNS) device during a laboratory session.

The study includes two task conditions. In one condition, participants will prepare a brief speech under evaluative conditions designed to induce stress. In the other condition, participants will complete a non-evaluative writing task. During the session, participants will wear a heart rate monitor and complete short questionnaires assessing their current feelings, including state anxiety.

The primary objective is to determine whether active tVNS is associated with lower state anxiety during a performance-related stress task compared to placebo stimulation. Secondary outcomes include heart rate and task-related responses. The study will also examine whether individual differences in stress reactivity influence responses to stimulation.

Participation involves one laboratory session lasting approximately 45 minutes.

Study Overview

• Status: Not yet recruiting
• Conditions: Stress Response
• Intervention / Treatment: Device: Transcutaneous Vagus Nerve Stimulation (tVNS); Behavioral: Evaluative Stress Task

Detailed Description

This study is a laboratory-based, randomized, double-blind experiment designed to examine whether non-invasive transcutaneous vagus nerve stimulation (tVNS) influences state anxiety and physiological arousal during performance-related stress.

Participants will be randomly assigned to one of four conditions in a 2 × 2 between-subjects factorial design:

Device Condition:

Active tVNS

Placebo (inactive) tVNS

Task Condition:

Stress Task (Modified Trier Social Stress Test speech preparation)

Control Task (Non-evaluative writing task)

The device condition is double blind. Half of the devices are configured by the manufacturer to deliver active stimulation to the auricular branch of the vagus nerve via the left ear. The remaining devices are configured to deliver brief initial stimulation that ramps down to zero (placebo condition). Neither participants nor experimenters are aware of device assignment during the session.

After informed consent and baseline measures, participants complete a quiet baseline period during which heart rate and state anxiety are assessed. Participants then wear the tVNS device during structured laboratory tasks.

In the stress condition, participants are instructed to prepare a five-minute speech to be delivered before evaluators and recorded for assessment. The preparation phase is modeled after the Trier Social Stress Test and is designed to induce anticipatory evaluative stress. The speech is not ultimately delivered. State anxiety and heart rate are measured during preparation and immediately afterward.

In the control condition, participants complete a non-evaluative writing task on the same topic without evaluative framing. Physiological and self-report measures are collected at matched time points.

The primary outcome measure is state anxiety assessed using the short-form State-Trait Anxiety Inventory (STAI). Secondary outcomes include heart rate measured during baseline, task preparation, and recovery periods. Additional measures include dispositional stress reactivity, which will be examined as a potential moderator of stimulation effects.

The study is designed to determine whether active tVNS reduces subjective anxiety and physiological arousal during evaluative stress compared to placebo stimulation and to assess whether effects differ as a function of individual differences in stress reactivity.

Participation consists of a single laboratory session lasting approximately 45 minutes.

• Study Type: Interventional
• Enrollment (Estimated): 200
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Pedepo Emmanuel, Organizational Behavior; Phone Number: 813-834-7991; Email: pedepo.emmanuel@warrington.ufl.edu

Study Locations

• United States
  • Florida
    • Gainesville, Florida, United States, 32611
      • University of Florida
      • Contact: Trevor Foulk, PhD in Management; Phone Number: 301-807-0397; Email: Trevor.foulk@warrington.ufl.edu

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

- Adults aged 18 to 65 years

Fluent in English

Able to provide informed consent

Able to complete study procedures during a single laboratory session

Exclusion Criteria:

- History of neurological or psychiatric disorders

Cardiovascular disease or uncontrolled hypertension

Implanted electrical devices (e.g., pacemaker)

Current pregnancy

Contraindications to transcutaneous vagus nerve stimulation (tVNS)

Current use of medications that significantly affect autonomic nervous system functioning

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: Randomized
• Interventional Model: Factorial Assignment
• Masking: Triple

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Active tVNS; Participants receive active transcutaneous vagus nerve stimulation (tVNS). Participants also complete either an evaluative stress task or a non-evaluative control task as part of the factorial design.	Device: Transcutaneous Vagus Nerve Stimulation (tVNS); Transcutaneous vagus nerve stimulation delivered via an auricular stimulation device. Participants receive either active stimulation or sham stimulation depending on random assignment; Behavioral: Evaluative Stress Task; Participants complete either an evaluative stress-induction task involving social evaluation or a non-evaluative control task. Task condition is assigned as part of the factorial design.
Sham Comparator: Sham Comparator; Participants receive sham transcutaneous vagus nerve stimulation. Participants also complete either an evaluative stress task or a non-evaluative control task as part of the factorial design.	Device: Transcutaneous Vagus Nerve Stimulation (tVNS); Transcutaneous vagus nerve stimulation delivered via an auricular stimulation device. Participants receive either active stimulation or sham stimulation depending on random assignment; Behavioral: Evaluative Stress Task; Participants complete either an evaluative stress-induction task involving social evaluation or a non-evaluative control task. Task condition is assigned as part of the factorial design.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Self-Reported Stress	Self-reported stress assessed using a questionnaire/scale administered before and after the performance task to capture changes in perceived stress during the laboratory session.	Baseline (pre-task) and immediately post-task during a single laboratory session.

Collaborators and Investigators

• Sponsor: University of Florida
• Investigators: Study Director: Trevor Foulk, Organizational Behavior, University of Florida; Study Director: Dustin Hegland, MD-ANESTHESIOLOGY-GENERAL, University of Florida

Study record dates

Study Major Dates

• Study Start (Estimated): March 15, 2026
• Primary Completion (Estimated): April 15, 2026
• Study Completion (Estimated): April 15, 2026

Study Registration Dates

• First Submitted: March 10, 2026
• First Submitted That Met QC Criteria: March 10, 2026
• First Posted (Actual): March 13, 2026

Study Record Updates

• Last Update Posted (Actual): March 13, 2026
• Last Update Submitted That Met QC Criteria: March 10, 2026
• Last Verified: February 1, 2026

More Information

Terms related to this study

• Keywords: transcutaneous vagus nerve stimulation tVNS, stress regulation state anxiety , Trier Social Stress Test, performance
• Additional Relevant MeSH Terms: Wounds and Injuries; Fractures, Bone; Fractures, Stress
• Other Study ID Numbers: IRB202600279

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO
• IPD Plan Description: Individual participant data will not be shared due to confidentiality considerations and institutional data protection policies. Although research data will be de-identified and stored securely, there are no current plans to make individual-level data publicly available. Aggregate results may be reported in publications and presentations.

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: Yes
• product manufactured in and exported from the U.S.: No