Effect of Transcutaneous Auricular Stimulation of the Vagus Nerve on Functional Connectivity in the Brain at Rest (COVAGNIRS)

Clinique Les Trois Soleils

Status: Enrolling

Conditions: Chronic Stroke Patients

Treatments: Device: Active taVNS arm; Device: Sham Control arm

Study type: Interventional

Funder types: Other

Identifiers

NCT07282106

2025-A01694-45

25.03521.000408 (Registry Identifier)

Details and patient eligibility

About

The goal of this clinical trial is to study the effect of Transcutaneous Auricular Vagus Nerve Stimulation (taVNS) on resting-state brain functional connectivity. The study will assess this effect using functional Near-Infrared Spectroscopy (fNIRS) in both chronic post-stroke patients and healthy subjects.

The main questions it aims to answer are:

Does taVNS affect resting-state functional connectivity (measured by fNIRS) in chronic post-stroke patients?

Does taVNS affect resting-state functional connectivity (measured by fNIRS) in healthy subjects?

Are there differences in the effect of taVNS on functional connectivity between the post-stroke group and the healthy group?

Researchers will compare the effect of active taVNS (real stimulation) to a sham stimulation (control) to evaluate its specific impact on the brain's functional networks.

Enrollment: 84 estimated patients

Sex: All

Ages: 18+ years old

Volunteers: Accepts Healthy Volunteers

Inclusion and exclusion criteria

Inclusion Criteria for post-stroke participant:

• age 18 or older
• Right-handed participant;
• Hemiparesis in the chronic phase (>6 months post-stroke)
• Participant who has agreed to sign an informed consent form;
• Participant who is affiliated with social security.

Inclusion Criteria for healthy participant:

• age 18 or older
• Right-handed participant;
• Participant who has agreed to sign an informed consent form;
• Participant who is affiliated with social security.

Exclusion Criteria for post-stroke participant:

• Allergy to neoprene (the material used to make the fNIRS cap);
• Hair volume preventing the cap from being put on and/or access to the scalp;
• Cognitive impairment making it impossible to participate in the study;
• Phasic disorders preventing understanding of instructions and effective communication;
• Pregnant or breastfeeding women;
• Persons under legal protection

Exclusion Criteria for post-stroke participant:

• Allergy to neoprene (the material used to make the fNIRS cap);
• Hair volume preventing the cap from being put on and/or access to the scalp;
• Pregnant or breastfeeding women;
• Persons under legal protection

Trial design

Primary purpose: Other

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Single Blind

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84 participants in 2 patient groups

Active taVNS arm

Experimental group

Description:

Transcutaneous Auricular Vagus Nerve Stimulation (taVNS): Delivery of low-intensity electrical impulses to the outer ear (concha and tragus) to stimulate the auricular branch of the vagus nerve.

Treatment:

Device: Active taVNS arm

Sham Control arm

Sham Comparator group

Description:

Simulated/Placebo Stimulation (Sham): Application of the device without delivering an active electrical current, serving as the necessary control condition.

Treatment:

Device: Sham Control arm