Vagus Nerve Stimulation in Patients in Comatose State

July 17, 2026 updated by: Sima Mofakham

Dual-Site Transcutaneous Auricular Nerve Stimulation (taVNS + taTNS) for Disorders of Consciousness After Traumatic Brain Injury: A Pilot Efficacy Study

Some patients with severe traumatic brain injury cannot respond at the bedside, yet about 1 in 4 may be aware but unable to show it - a hidden state called cognitive motor dissociation. This study tests a gentle, non-invasive treatment delivered through clips on the left ear that stimulates two nerves at once: the vagus nerve at the inner ear (taVNS) and the trigeminal nerve at the outer ear (taTNS). Each nerve has separately been shown to help people with disorders of consciousness recover, but they have not been combined before. All enrolled patients receive the stimulation for one hour a day, with continuous heart and oxygen monitoring and a pain-protection check used to keep the dose safe. The study measures recovery two ways: the Coma Recovery Scale-Revised (CRS-R), scored by clinicians, and SeeMe, an automated camera system that detects tiny command-driven movements the eye cannot see.

Study Overview

Status

Status

Indicates the current recruitment status or the expanded access status.
Recruiting

Conditions

Conditions

The disease, disorder, syndrome, illness, or injury that is being studied. On ClinicalTrials.gov, conditions may also include other health-related issues, such as lifespan, quality of life, and health risks.

Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.

Detailed Description

This prospective, single-center, open-label, single-arm pilot study enrolls a subcohort of comatose TBI patients from the parent SeeMe study (NCT07560631) whose legally authorized representative consents to a stimulation addendum. Dual-site transcutaneous auricular nerve stimulation is delivered to the left ear: the vagal site (cymba conchae) targets the auricular branch of the vagus nerve, and the trigeminal site (outer ear) targets the auriculotemporal branch - each with distinct, optimized parameters. Mechanistically, vagal afferents project to the nucleus tractus solitarius and the ascending reticular activating system to promote arousal, while trigeminal afferents project via the spinal trigeminal nucleus to thalamus and cortex to enhance thalamocortical connectivity; the dual-site paradigm aims to drive the cortico-striatal-thalamic-cortical loop from two convergent directions. Baseline assessment captures CRS-R, GCS, vital signs, NCS-R, heart-rate variability, and EEG. Daily one-hour sessions include pre/post vitals, NCS-R-guided titration, continuous telemetry, ear-site inspection, and daily CRS-R. In parallel, the SeeMe computer-vision platform quantifies stimulus-evoked facial and hand movements. The course runs 7 consecutive days, extendable to 28 days. Findings will inform a future sham-controlled randomized trial and closed-loop integration with SeeMe.

Study Type

Study Type

Describes the nature of a clinical study. Study types include interventional studies (also called clinical trials), observational studies (including patient registries), and expanded access.
Interventional

Enrollment (Estimated)

Enrollment

The number of participants in a clinical study. The "anticipated" enrollment is the target number of participants that the researchers need for the study.
10

Phase

Phase

The stage of a clinical trial studying a drug or biological product, based on definitions developed by the U.S. Food and Drug Administration (FDA). The phase is based on the study's objective, the number of participants, and other characteristics. There are five phases: Early Phase 1 (formerly listed as Phase 0), Phase 1, Phase 2, Phase 3, and Phase 4. Not Applicable is used to describe trials without FDA-defined phases, including trials of devices or behavioral interventions.
  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Study Contact

The name and contact information for the person who can answer enrollment questions for a clinical study. Each location where the study is being conducted may also have a specific contact, who may be better able to answer those questions.

Study Locations

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Eligibility Criteria

The key requirements that people who want to participate in a clinical study must meet or the characteristics they must have. Eligibility criteria consist of both inclusion criteria (which are required for a person to participate in the study) and exclusion criteria (which prevent a person from participating). Types of eligibility criteria include whether a study accepts healthy volunteers, has age or age group requirements, or is limited by sex.

Ages Eligible for Study

  • Adult
  • Older Adult

Accepts Healthy Volunteers

No

Description

Inclusion Criteria:

  • Age ≥ 18 years
  • Coma, vegetative state/unresponsive wakefulness syndrome (VS/UWS), or minimally conscious state (MCS) as determined by baseline CRS-R
  • Acute traumatic brain injury with documented intracranial pathology on neuroimaging
  • Admission to the Neurology or Neurosurgical ICU
  • Legally authorized representative (LAR) available and willing to consent, including the Stimulation Addendum Consent Form

Exclusion Criteria:

  • Implanted cardiac pacemaker, vagus nerve stimulator, or other active implanted device
  • Known cardiac arrhythmia (e.g., 2nd-/3rd-degree AV block, atrial fibrillation with uncontrolled rate)
  • Active seizures not controlled by current antiepileptic regimen
  • Skin breakdown, infection, or anatomical abnormality of the left ear precluding electrode placement
  • Pregnancy
  • Hemodynamic instability requiring vasopressor escalation at the time of enrollment

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Treatment
  • Allocation: N/A
  • Interventional Model: Single Group Assignment
  • Masking: None (Open Label)

Arms and Interventions

Participant Group / Arm

Participant Group / Arm

A group or subgroup of participants in a clinical trial that receives a specific intervention/treatment, or no intervention, according to the trial's protocol.
Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.
Experimental: Dual-site auricular stimulation (taVNS + taTNS)
Experimental: Dual-site auricular stimulation (taVNS + taTNS). All enrolled participants receive active vagal and trigeminal auricular stimulation.
Device: Dual-Site Transcutaneous Auricular Nerve Stimulation (taVNS + taTNS)
DEVICE: Dual-Site Transcutaneous Auricular Nerve Stimulation (taVNS + taTNS). Delivered via ear-clip electrodes on the LEFT ear using the Sparrow Ascent / Sparrow Link tAN System (Spark Biomedical; FDA-cleared K230796), operated as an NSR investigational device. Vagal site (inner ear / cymba conchae): 15 Hz, 250 µs pulse width, 3 mA fixed, duty cycle 5 min on / 10 s off. Trigeminal site (outer ear): 100 Hz, 250 µs pulse width, 3 mA fixed, duty cycle 5 min on / 10 s off. Session: 1 hour/day. Course: 7 consecutive days, extendable to 28 days. Intensity titrated with the Nociception Coma Scale-Revised (NCS-R): step down 0.5 mA if NCS-R > 4/9, SpO2 ≤ 95%, or HR rises ≥ 20 bpm; continuous cardiac/hemodynamic monitoring with prespecified stopping rules.

What is the study measuring?

Primary Outcome Measures

Primary Outcome Measures

In a clinical study's protocol, the planned outcome measure that is the most important for evaluating the effect of an intervention/treatment. Most clinical studies have one primary outcome measure, but some have more than one.
Outcome Measure
Measure Description
Time Frame
Change in Coma Recovery Scale-Revised (CRS-R) Total Score
Time Frame: Baseline to Day 7, or baseline to Day 28 for participants with extended treatment
Change in level of consciousness will be assessed using the Coma Recovery Scale-Revised total score. The outcome will be reported as the within-participant change in total score from baseline to the end of treatment, as scored by a trained assessor. Scores range from 0 to 23, with higher scores indicating better neurobehavioral function and greater recovery of consciousness.
Baseline to Day 7, or baseline to Day 28 for participants with extended treatment
Change in SeeMe-Detected Stimulus-Evoked Voluntary Motor Responses
Time Frame: Baseline to Day 7, or baseline to Day 28 for participants with extended treatment
Change in command-evoked voluntary motor responses will be assessed using the SeeMe automated camera-based detection system. The outcome will be reported as the within-participant change in the percentage of command trials with SeeMe-positive responses from baseline to the end of treatment. Scores range from 0% to 100%, with higher percentages indicating more frequent command-evoked voluntary motor responses. A SeeMe-positive response is defined as a Kolmogorov-Smirnov statistic greater than 0.1 and pixel displacement greater than 400, detected reliably in at least 3 of 10 command trials. SeeMe scoring will be automated and performed blinded to stimulation timing.
Baseline to Day 7, or baseline to Day 28 for participants with extended treatment

Secondary Outcome Measures

Secondary Outcome Measures

In a clinical study's protocol, a planned outcome measure that is not as important as the primary outcome measure for evaluating the effect of an intervention but is still of interest. Most clinical studies have more than one secondary outcome measure.
Outcome Measure
Measure Description
Time Frame
Number of Participants With Device- or Stimulation-Related Adverse Events
Time Frame: Baseline to Day 7, or baseline to Day 28 for participants with extended treatment
Adverse events attributed to auricular stimulation will be recorded and graded using CTCAE v5.0, including ear-site skin reactions, bradycardia or other arrhythmia, oxygen desaturation, and hemodynamic instability. Events requiring NCS-R-guided dose reduction or meeting prespecified stopping criteria will be reported.
Baseline to Day 7, or baseline to Day 28 for participants with extended treatment

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Sponsor

The organization or person who initiates the study and who has authority and control over the study.
Sima Mofakham

Collaborators

Collaborators

An organization other than the sponsor that provides support for a clinical study. This support may include activities related to funding, design, implementation, data analysis, or reporting.
National Institute of Mental Health (NIMH)

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

Study Start

The actual date on which the first participant was enrolled in a clinical study. The "anticipated" study start date is the date that the researchers think will be the study start date.
June 26, 2026

Primary Completion (Estimated)

Primary Completion

The date on which the last participant in a clinical study was examined or received an intervention to collect final data for the primary outcome measure. Whether the clinical study ended according to the protocol or was terminated does not affect this date. For clinical studies with more than one primary outcome measure with different completion dates, this term refers to the date on which data collection is completed for all the primary outcome measures. The "anticipated" primary completion date is the date that the researchers think will be the primary completion date for the study.
December 1, 2029

Study Completion (Estimated)

Study Completion

The date on which the last participant in a clinical study was examined or received an intervention/treatment to collect final data for the primary outcome measures, secondary outcome measures, and adverse events (that is, the last participant's last visit). The "anticipated" study completion date is the date that the researchers think will be the study completion date.
December 1, 2029

Study Registration Dates

First Submitted

First Submitted

The date on which the study sponsor or investigator first submitted a study record to ClinicalTrials.gov. There is typically a delay of a few days between the first submitted date and the record's availability on ClinicalTrials.gov (the first posted date).
June 26, 2026

First Submitted That Met QC Criteria

First Submitted That Met QC Criteria

The date on which the study sponsor or investigator first submits a study record that is consistent with National Library of Medicine (NLM) quality control (QC) review criteria. The sponsor or investigator may need to revise and submit a study record one or more times before NLM's QC review criteria are met. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
July 17, 2026

First Posted (Actual)

First Posted

The date on which the study record was first available on ClinicalTrials.gov after National Library of Medicine (NLM) quality control (QC) review has concluded. There is typically a delay of a few days between the date the study sponsor or investigator submitted the study record and the first posted date.
July 22, 2026

Study Record Updates

Last Update Posted (Actual)

Last Update Posted

The most recent date on which changes to a study record were made available on ClinicalTrials.gov. There may be a delay between when the changes were submitted to ClinicalTrials.gov by the study's sponsor or investigator (the last update submitted date) and the last update posted date.
July 22, 2026

Last Update Submitted That Met QC Criteria

Last Update Submitted That Met QC Criteria

The most recent date on which the study sponsor or investigator submitted changes to a study record that are consistent with National Library of Medicine (NLM) quality control (QC) review criteria. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
July 17, 2026

Last Verified

Last Verified

The most recent date on which the study sponsor or investigator confirmed the information about a clinical study on ClinicalTrials.gov as accurate and current. If a study with a recruitment status of recruiting; not yet recruiting; or active, not recruiting has not been confirmed within the past 2 years, the study's recruitment status is shown as unknown.
June 1, 2026

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

Other Study ID Numbers

Identifiers or ID numbers other than the NCT number that are assigned to a clinical study by the study's sponsor, funders, or others. These numbers may include unique identifiers from other trial registries and National Institutes of Health grant numbers.
  • IRB2019-00199 MOD061
  • R61MH138612 (U.S. NIH Grant/Contract)

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

YES

IPD Plan Description

De-identified individual participant data underlying published results will be shared, including CRS-R scores, SeeMe-derived movement metrics, stimulation parameters, and safety data. Data will be available following publication of the primary results. Requests will be reviewed by the study team and require a data use agreement and confirmation of appropriate IRB or ethics approval. Raw facial video will not be shared due to the inherent re-identifiability of facial imagery; derived quantitative movement features will be shared instead.

IPD Sharing Time Frame

Beginning 12 months after publication of the primary results and ending 5 years following publication.

IPD Sharing Access Criteria

Access will be granted to qualified investigators whose proposed use has been approved by the study team. Requestors must submit a methodologically sound research proposal and a signed data use agreement, and must provide documentation of IRB or equivalent ethics approval for the proposed analysis. Approved requestors will receive de-identified individual participant data, including CRS-R scores, SeeMe-derived quantitative movement metrics, stimulation parameters, and safety data, together with the study protocol, statistical analysis plan, and blank informed consent form. Raw facial video will not be released due to the inherent re-identifiability of facial imagery. Requests should be directed to the principal investigator at sima.mofakham@stonybrookmedicine.edu.

IPD Sharing Supporting Information Type

  • STUDY_PROTOCOL
  • SAP
  • ANALYTIC_CODE

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

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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