tVNS During Motor Training in Older Adults

Pairing tVNS With Motor Skill Training in Older Adults

The goal of this study is to learn about the effect of applying transcutaneous vagus nerve stimulation (tVNS) during motor training on motor learning in older adults. The main question it aims to answer is whether applying tVNS after successful motor trials (post-success tVNS) will facilitate the rate of motor learning. Participants will be randomly assigned to tVNS or sham group and receive tVNS or sham, respectively, at the outer ear during finger control training sessions. Finger control performance will be tested before and after the training sessions without outer ear stimulation.

Study Overview

• Status: Recruiting
• Conditions: Older Adults
• Intervention / Treatment: Procedure: tVNS stimulation; Procedure: Sham stimulation

Detailed Description

The participants will be randomly assigned to a tVNS or control group. They will visit the lab for four sessions. The main motor task is to trace target trajectories with finger forces. As the pre- and post-tests, all participants will be tested on a force tracing motor task with the left hand. There will be no electrical stimulation during the tests. During the training sessions, all participants will wear surface electrodes on the outer ear. The attachment sites are the tragus or cymba concha (depending on the shape and size of the ear) for the tVNS group and the earlobe for the sham group. The participants will perform finger training to trace target trajectories with their left finger forces. Participants in the tVNS and sham group will receive tVNS and sham stimulation, respectively, after successful finger trials.

• Study Type: Interventional
• Enrollment (Estimated): 32
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Minoru Shinohara, PhD; Phone Number: 4048941030; Email: shinohara@gatech.edu

Study Locations

• United States
  • Georgia
    • Atlanta, Georgia, United States, 30332
      • Recruiting
      • Human Neuromuscular Physiology Lab
      • Contact: Minoru Shinohara, Ph.D.; Phone Number: 404-894-1030; Email: shinohara@gatech.edu
      • Principal Investigator: Minoru Shinohara, Ph.D.

Participation Criteria

Eligibility Criteria

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

Description

Inclusion Criteria:

• 65-84 years old across all races, genders, and ethnicities.
• Right-handed
• Physically and cognitively healthy

Exclusion Criteria:

• Younger than 65 years old or older than 84 years old
• Current or history of cardiac disease
• Have an implanted device such as a neurostimulator or cochlear implant
• Current or history of tympanic membrane perforation
• Have a musculoskeletal issue that prevents hand function (e.g., arthritis)
• Have a vision problem not corrected by glasses or contact lenses
• Uncorrected auditory impairments
• Had a stroke or lesion (including tumor) in the brain
• Had a head injury or brain surgery
• Suffer from frequent or severe headaches
• Had a fainting spell or syncope
• Have any metal in the head such as shrapnel, surgical clips, or fragments from welding or metal work
• Have any implanted device such as cardiac pacemakers, medical pumps, or intracardiac lines
• Had any brain-related conditions (i.e. multiple sclerosis, Parkinson, Alzheimer)
• Had any illness that caused brain injury (i.e. meningitis, aneurysm, brain tumor)
• Had any head trauma that was associated with a loss of consciousness or diagnosed as a concussion
• Being treated for any psychiatric condition (i.e. depression, anxiety, PTSD, schizophrenia)
• Suspected of pregnancy
• Pregnant
• Cognitive status issues as confirmed with the Mini-Mental State Exam (MMSE <26)
• Musculoskeletal condition or injury that would limit hand range of motion

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Double

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: tVNS stimulation; Brief electrical current will be applied to the vagus nerve area (the tragus or cymba concha, depending on the shape and size of the ear) immediately after successful trials during finger control training.	Procedure: tVNS stimulation; Electrical stimulation to the vagus nerve area.
Sham Comparator: Sham stimulation; Brief electrical current will be applied to the non-vagus nerve area (the earlobe) immediately after successful trials during finger control training.	Procedure: Sham stimulation; Electrical stimulation to the non-vagus nerve area.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Rate of error reduction	The slope of the reduction in the root mean square error of finger force	2 weeks

Collaborators and Investigators

• Sponsor: Georgia Institute of Technology
• Collaborators: University of Florida
• Investigators: Principal Investigator: Minoru Shinohara, PhD, Georgia Institute of Technology

Study record dates

Study Major Dates

• Study Start (Actual): May 27, 2025
• Primary Completion (Estimated): June 30, 2026
• Study Completion (Estimated): July 31, 2026

Study Registration Dates

• First Submitted: March 15, 2024
• First Submitted That Met QC Criteria: March 15, 2024
• First Posted (Actual): March 21, 2024

Study Record Updates

• Last Update Posted (Actual): April 21, 2026
• Last Update Submitted That Met QC Criteria: April 16, 2026
• Last Verified: April 1, 2026

More Information

Terms related to this study

• Other Study ID Numbers: H24110

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: UNDECIDED

Drug and device information, study documents

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