Galvanic Vestibular Stimulation as a Novel Treatment for Seasickness

Study Overview
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Brief Summary
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subjects with severe seasickness, who failed to habituate to sea conditions after at least six month of active sailing, were enrolled to the single-blind randomized control study. The intervention group was treated with rotatory chair stimulation at sinusoidal harmonic acceleration protocol coupled with galvanic vestibular stimulation to the mastoid processes. This unique procedure was hypothesized to promote habituation to seasickness. The control group underwent a sham procedure. All study participants filled out seasickness questionnaires at set time points following the intervention and underwent repeated step testing to determine their vestibular time constant. The number of anti-motion sickness clinic visits and scopolamine prescriptions was also recorded in the three months period following the intervention.

Official Title
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Galvanic Vestibular Stimulation as a Novel Treatment for Seasickness

Conditions
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Seasickness, Motion Sickness, Habituation, Vestibular Time Constant

Intervention / Treatment
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* Procedure: GVS stimulation coupled with inverse phase rotatory chair stimulation at sinusoidal harmonic acceleration protocol
* Procedure: Sham procedure


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: maximum score of 7 on the Wiker seasickness questionnaire in moderate sea conditions, with wave height of 0 - 1.5 m All had been sailing regularly for at least six months before enrolling in the study Exclusion Criteria: history of hearing loss otoscopic findings of ear pathology an implanted electrode a finding of vestibulopathy on otoneurologic examination withdrawal by any subject of his informed consent.

Ages Eligible for Study
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Minimum Age: 19 Years
Maximum Age: 44 Years

Sexes Eligible for Study
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Male

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: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Sham Comparator: sham procedure<br>Participants with severe motion sickness were sited in the the rotatory chair with the videonystagmography recorder masking their eyes, while two galvanic vestibular stimulation electrodes were connected to the mastoid processes. No active stimulus was given. | Procedure: Sham procedure<br>* Participants with severe motion sickness were sited in the the rotatory chair with the videonystagmography recorder masking their eyes, while two galvanic vestibular stimulation electrodes were connected to the mastoid processes. No active stimulus was given.<br>|
| Experimental: GVS stimulation coupled with inverse phase rotatory chair stimulation<br>Participants with severe motion sickness were sited in the the rotatory chair with the videonystagmography recorder masking their eyes, while two galvanic vestibular stimulation electrodes were connected to the mastoid processes. The rotatory chair was activated in sinusoidal harmonic acceleration protocol in inverse phase to galvanic vestibular stimulation. | Procedure: GVS stimulation coupled with inverse phase rotatory chair stimulation at sinusoidal harmonic acceleration protocol<br>* GVS stimulation coupled with inverse phase rotatory chair stimulation at sinusoidal harmonic acceleration protocol<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Vestibular time constant | Vestibular time constant was measured using repeated rotatory chair stimulation in step protocol. | Until one month following the intervention | 
| Seasickness severity | Seasickness severity as determined by Wiker questionnaire at set time frames following the intervention | Until one month following the intervention | 
| scopolamine drug prescription | scopolamine drug prescriptions were calculated for each participant and compared between the two groups | Until three months following the intervention | 
| Anti-motion sickness clinic visits | Anti-motion sickness clinic visits were calculated for each participant and compared between the two groups | Until three months following the intervention | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Motion Sickness, Seasickness, Galvanic vestibular stimulation, Rotatory chair, Vestibular time constant