CompletedNot Applicable

Vestibular Cortex and TMS

France17 participantsStarted 2013-01-20

Plain-language summary

In human, the cerebral cortex forms a network of vestibular cortical areas which functional role remains unknown. In patients with localised cortical lesions the investigator has previously demonstrated that the parieto-temporal cortex could regulate the inertial component of the vestibulo-ocular (VOR) responses whereas more ventral regions including the temporo-occipital cortex would be associated with gain regulation of these VOR responses. The investigator's main purpose is to investigate the modalities of vestibular integration in these posterior parieto-temporal et temporo-occipital cortical regions. Thus, by using repetitive ttranscranial magnetic stimulation (rTMS) the investigator will induce a transitory inhibition of one of these 2 cortical regions and register its effect on VOR responses. Based on theta burst stimulation (TBS) paradigm, the investigator will stimulate the region of interest by applying on the scalp repetitive burst (at 50 HZ) during 44sec. Then, during the consecutive cortical inhibition lasting for the 15 minutes poststimulation, the investigator will record the subject's VOR responses. The VOR gain will be calculated and the time constant and phase will provide an estimation of the inertial component of the VOR responses. The healthy subjects recruited on the basis of inclusion criteria during medical examination will be divided into two groups of 20 subjects each depending of their sites of stimulation, temporo-parietal or temporo-occipital. Each subject will perform three experimental sessions (of 1h in average each) separated by at least one week and corresponding to : (1) the right cortical stimulation, (2) the left stimulation and (3) the vertex stimulation serving as the control session. The TMS paradigm is used in routine in hospital and research field and had very few negative consequences (mainly transitory and occasional headache).

Who can participate

Age range

20 Years – 35 Years

Sex

ALL

See this in plain English?

AI-rewrites the medical criteria so a patient or caregiver can understand them. Always confirm with the trial site.

Inclusion Criteria: * Male and/or female healthy volunteers between 20 and 35 years old. * Considered healthy subject after medical examination and MRI images analysis * With social security affiliation * After informed and voluntary consent to participate to the study (signed written consent) * With normal ocular responses with a gain not less than 0.5 during preliminary VOR registration. Exclusion Criteria: * Persons under guardianship, curatorship or any other administrative or judicial deprivation of rights and freedom * Persons with a medical history, or any acute or chronic disease which may affect the test results, or creating a risk to the subject in the protocol, in particular: * with personal or family history of seizure disorders * with previous or current psychiatric disease or schizotypal signs (RISC questionary) * with previous or current neurology or otology (audition or equilibrium) history * with visual corrected visual acuity inferior to 8/10 * having taken hypnotics, psychotropic or other central nervous system depressants (opiates, barbiturates, antiepileptics, antidepressants, sedatives, antihistamines, anxiolytics, neuroleptics, clonidine and related) during the 8 months prior to experimentation * consuming more than 150 mg of caffeine per day (15 small cups of Italian coffee) * with a contra-indication for MRI: pacemaker or neural surgical clips ferromagnetic and metallic implants, intraocular foreign bodies, claustrophobia * pregnan…

Questions worth asking your doctor

Bring these to your next appointment. They're a starting point for a shared conversation — not a sign you qualify or a recommendation to enrol.

1Based on my diagnosis and history, is this trial worth exploring for me — or is there a standard treatment we should try first?
2What does this trial's phase tell us about how much is already known about its safety and benefit?
3What would taking part actually involve for me — visits, tests, time, and travel?
4What are the known and possible risks or side effects I should weigh, and how would they be monitored?
5If this trial isn't the right fit, what other options or trials would you suggest I look into?

Generated to help you prepare — always confirm anything about your own eligibility and care with the study team and your doctor.

Questions for the trial coordinator

The trial coordinator is the person who runs the study day to day. These cover the practical side — logistics, costs, and what taking part would actually mean for your life. The study team confirms whether you meet the criteria; these are questions to ask, not a sign you qualify.

1What does taking part actually involve week to week — how many visits, where, and how long does each one take?
2What costs are covered by the study, and what might I have to pay for myself, including travel, parking, or time off work?
3What happens during screening, and what happens if the study team confirms I don't meet the criteria after those tests?
4Who pays for the scans, blood work, and other tests the trial requires — the study, my insurance, or me?
5How will being in the trial affect my regular care, and will my own doctor stay informed and involved?
6Can I leave the trial at any point if I change my mind, and what would happen to my care if I do?

A starting point for the conversation — always confirm anything about your own eligibility, costs, and care with the study team and your doctor.

What they're measuring

changes in gain of vestibulo-ocular reflex (VOR)

Timeframe: Day 1, Day 7, Day 14, Day 21

Trial details

NCT IDNCT01779752

SponsorInstitut National de la Santé Et de la Recherche Médicale, France

Sponsor typeOTHER_GOV

Study typeOBSERVATIONAL

Primary completion2016-01

View on ClinicalTrials.gov More Cortical Organisation of Vestibular Integration trials