Effect of Transcutaneous Vagal Nerve Stimulation on Reducing Visually Induced Motion Sickness in Healthy Volunteers

Study Overview
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Brief Summary
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Nausea is a common and distressing experience that often precedes vomiting. Amongst symptoms emanating from the gastrointestinal (GI) tract nausea can be considered somewhat unique, as on one hand it represents a normal, highly conserved, physiological response to an ingested toxin yet on the other it may indicate pathology. Nausea may also arise as a consequence of pharmaco- and chemotherapeutic interventions. Nausea negatively impacts on quality of life, adherence to treatment and is a cause for discontinuation of the development of novel compounds. Experimentally, nausea can be induced in humans using a visually induced motion stimulus. Previously we have developed a 10-minute motion video of the landscape rotating as seen from the perspective of a subject standing on Westminster Bridge, London. The tilted and rotating view visual display makes the subject perceive that they are spinning round and round on a spot tilted away from centre of gravity due to circular vection. This motion video induced nausea in approximately 50% of healthy participants and caused a reduction in cardiac vagal tone, a validated measure of the parasympathetic nervous system branch on the autonomic nervous system. We therefore are evaluating the role of external transcutaneous vagal nerve stimulation in visually induced motion sickness.

Official Title
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Effect of Transcutaneous Vagal Nerve Stimulation on Reducing Visually Induced Motion Sickness in Healthy Volunteers

Conditions
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Visually Induced Motion Sickness in Healthy Volunteers

Intervention / Treatment
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* Device: Transcutaneous vagal nerve stimulation
* Device: Sham vagal nerve stimulation


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Healthy subjects, aged 18-65, from staff, students and local population of Queen Mary, University of London. Inclusion will be determined on the basis of availability, with no prior selection bias included. They should be able to attend the Wingate Institute for at least 2 x 1 hour sessions. Subjects who score >15 on MSSQ (suggesting that they are sensitive to visually induced nausea). Exclusion Criteria: Subjects unable to provide informed consent. Subjects with any systemic disease or medications that may influence the autonomic nervous system (e.g. beta-agonists or Parkinson's disease). Subjects who score <15 on MSSQ (suggesting that they are insensitive to visually induced nausea). Pregnant females to prevent any confounding effects on pregnancy related nausea.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 75 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Triple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Transcutaneous vagal nerve stimulation<br>Active vagal nerve stimulation to the left auricular branch of the vagus nerve | Device: Transcutaneous vagal nerve stimulation<br> <br> * Other names: NEMOS;|
| Placebo Comparator: Sham vagal nerve stimulation<br>Placebo vagal nerve stimulation - stimulator attached to the ear but rotated 180 degrees so that it is not stimulating the vagus nerve. | Device: Sham vagal nerve stimulation<br> <br> |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Reduction of the subjective sensation of nausea on a visual analogue scale |  | 10 minutes | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Effect of transcutaneous vagal nerve stimulation on cardiac vagal tone |  | 10 minutes | 
| Tolerability of transcutaneous vagal nerve stimulation |  | 10 minutes |