Mastoid taVNS-fMRI

NCT ID: NCT06518356

Last Updated: 2025-07-04

Basic Information

• Recruitment Status: COMPLETED
• Clinical Phase: NA
• Total Enrollment: 24 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2024-08-26
• Study Completion Date: 2025-04-28

Brief Summary

The purpose of this study is to explore whether stimulating different outer parts of the ear using a non-invasive form of ear stimulation called transcutaneous auricular vagus nerve stimulation (taVNS) will create different brain activation images. Investigators will recruit 24 healthy participants. The ear stimulation will be delivered while taking brain images using a magnetic resonance imaging (MRI) machine.

Detailed Description

Transcutaneous auricular vagus nerve stimulation (taVNS) is a non-invasive neuromodulation technique that delivers electric stimulation to the auricular branch of the vagus nerve (ABVN). This technique has been demonstrated effective in the treatment of depression and addiction in previous studies.

Most previous applications of taVNS targeted the ABVN via the cymba conchae or tragus sites. The mastoid process (mastoid site) is an important dermatome innervated by the ABVN, but there is currently a lack of knowledge on how taVNS on the mastoid site affects brain activity and whether it differs from the effect of stimulating the cymba site.

In this proposed study, the investigators plan to explore whether delivering taVNS to the mastoid site and the cymba site can induce different patterns of brain activity. Ultimately, if successful, this project will not only deepen our knowledge in basic neuroscience but also have great value in clinical applications since the mastoid site is a much more accessible ABVN target compared to other sites.

Conditions

Auricular Stimulation

Study Design

• Allocation Method: RANDOMIZED
• Intervention Model: SINGLE_GROUP
• Primary Study Purpose: TREATMENT
• Blinding Strategy: SINGLE

Study Groups

Auricular Neurostimulation (Active 1)

•Within the MRI scanner, each participant will be connected to a series of tAN electrodes that stimulate the following ear target

-Cymba stimulation (15Hz stimulation of cymba conchae)

Group Type: ACTIVE_COMPARATOR

Transcutaneous Auricular Neurostimulation (tAN)

Intervention Type: DEVICE

The intervention the investigators are studying is called transcutaneous auricular neurostimulation (tAN). tAN is simply electrical nerve stimulation administered at the ear which targets the auricular branch of the vagus nerve (ABVN) at the cymba conchae and mastoid process, and to a sham site (earlobe).

Auricular Neurostimulation (Active 2)

•Within the MRI scanner, each participant will be connected to a series of tAN electrodes that stimulate the following ear target

-Mastoid stimulation (15Hz stimulation of mastoid process)

Group Type: ACTIVE_COMPARATOR

Transcutaneous Auricular Neurostimulation (tAN)

Intervention Type: DEVICE

The intervention the investigators are studying is called transcutaneous auricular neurostimulation (tAN). tAN is simply electrical nerve stimulation administered at the ear which targets the auricular branch of the vagus nerve (ABVN) at the cymba conchae and mastoid process, and to a sham site (earlobe).

Auricular Neurostimulation (Sham 1)

•Within the MRI scanner, each participant will be connected to a series of tAN electrodes that stimulate the following ear target

-Sham (15Hz stimulation of the earlobe)

Group Type: SHAM_COMPARATOR

Transcutaneous Auricular Neurostimulation (tAN)

Intervention Type: DEVICE

The intervention the investigators are studying is called transcutaneous auricular neurostimulation (tAN). tAN is simply electrical nerve stimulation administered at the ear which targets the auricular branch of the vagus nerve (ABVN) at the cymba conchae and mastoid process, and to a sham site (earlobe).

Interventions

Transcutaneous Auricular Neurostimulation (tAN)

The intervention the investigators are studying is called transcutaneous auricular neurostimulation (tAN). tAN is simply electrical nerve stimulation administered at the ear which targets the auricular branch of the vagus nerve (ABVN) at the cymba conchae and mastoid process, and to a sham site (earlobe).

Intervention Type: DEVICE

Eligibility Criteria

Inclusion Criteria

• Age 18-65
• Have the capacity and ability to provide one's own consent in English and sign the informed consent document.

Exclusion Criteria

• Unable to speak in English.
• Contraindicated for MRI.
• Any current or recent untreated medical, neurological, or psychiatric conditions
• Metal implant devices in the head, heart or neck.
• History of brain surgery.
• History of myocardial infarction or arrhythmia, bradycardia.
• Personal or family history of seizure or epilepsy or personal use of medications that substantially reduce seizure threshold (e.g., olanzapine, chlorpromazine, lithium).
• Personal history of head injury, concussion, or self-report of moderate to severe traumatic brain injury.
• Participant has abnormal ear anatomy, skin irritation, or ear infection present
• Individuals suffering from frequent/severe headaches.
• Individuals with a reported history of psychosis or mania, or individuals who are actively manic or psychotic.
• Moderate to severe alcohol or substance use disorder.
• Pregnancy

• Minimum Eligible Age: 18 Years
• Maximum Eligible Age: 65 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: Yes

Sponsors

Medical University of South Carolina

OTHER

Sponsor Role: lead

Responsible Party

Xiaolong Peng

Research Instructor-Faculty

Responsibility Role: PRINCIPAL_INVESTIGATOR

Principal Investigators

Xiaolong Peng

Role: PRINCIPAL_INVESTIGATOR

Medical University of South Carolina

Locations

Medical University of South Carolina Institute of Psychiatry

Charleston, South Carolina, United States

Countries

United States

Other Identifiers

Pro00137424

Identifier Type: -

Identifier Source: org_study_id