Clinical trial NCT05198440: Neuromodulation of Motion Illusions (Vection)
Official title: Neuromodulation of Motion Illusions (Vection)
Study type: INTERVENTIONAL
Overall status: UNKNOWN
Phase: NA
Conditions: Healthy
Keywords: vection
neuromodulation
rTMS
tACS
Lead sponsor: University Hospital, Grenoble
Sponsor class: OTHER
First posted: 2022-01-20
Enrollment: 90
Sex: ALL
Minimum age (years): 18
Maximum age (years): 40
Standard ages: ADULT
Accepts healthy volunteers: yes
Allocation: NA
Intervention model: SINGLE_GROUP
Primary purpose: BASIC_SCIENCE

Brief summary: Virtual reality systems or simulators are more and more frequently used in the field of learning but also in motor rehabilitation. One of the key points of the success of these systems is the experience of "presence" which is associated with the capacity of these technologies to develop in the observer, who is static, the sensation of moving in the virtual environment (vection). However, the simulation generates a sensory conflict (an optical flow specifying self-motion and vestibular stimuli specifying body immobility). This conflict influences the temporal characteristics of the vection and consequently modifies the way users act in their virtual environment. Thus, contrary to a real situation, vection does not occur instantaneously with the appearance of a visual movement. Moreover, the visual stimulus often generates alternating periods of perception of movement of the environment and of oneself (bistable perception) which can lead to "simulator sickness", a disabling situation for the user. Thus, as vection is an essential element to allow an "optimal transfer of learning" from the simulator to reality, it may be important to promote its emergence while limiting its bistability.

The aim of this project is to study the inhibitory or facilitative modulation of the emergence of the vection phenomenon by the use of non-invasive cortical stimulation techniques (transcranial electrical stimulation (tES), transcranial alternative current stimulation (tACS), and repeated transcranial magnetic stimulation (rTMS)).


Eligibility criteria: Inclusion Criteria:

* Healthy subjects aged 18 to 40 years
* Right-handed subjects
* Signed informed consent,
* Medical examination performed prior to participation in the research,
* Affiliation to or beneficiary of a social security plan

Exclusion Criteria:

* Contraindications (CI) to the practice of MRI, EEG, TMS \& tES
* Existence of a severe general condition: cardiac, respiratory, hematological, renal, hepatic, cancerous,
* Regular use of anxiolytics, sedatives, antidepressants, neuroleptics,
* Characterized psychiatric pathology,
* Ingestion of alcohol before the examination,
* Pregnant, parturient or breastfeeding women
* Person deprived of liberty by judicial or administrative decision, person under a legal protection measure (under guardianship or curators)
* Participation in other interventional research protocols in progress with an exclusion period or in the previous week Subject who would receive more than 4500 euros of compensation due to his participation in other research involving the human person in the 12 months preceding this study

Primary outcomes:
measure: Change in the latency of first vection between neuromodulations
timeFrame: During the two experimental sessions, at day 1 and up to day 15
measure: Change in the vection frequency between neuromodulations
timeFrame: During the two experimental sessions, at day 1 and up to day 15
measure: Change in the vection duration between neuromodulations
timeFrame: During the two experimental sessions, at day 1 and up to day 15
measure: Change in the vection intensity between neuromodulations
timeFrame: During the two experimental sessions, at day 1 and up to day 15
Secondary outcomes:
measure: Change in brain activity (as measured by EEG - EP) between neuromodulations
timeFrame: During the two experimental sessions, at day 1 and up to day 15
measure: Change in brain activity (as measured by EEG - spectrum) between neuromodulations
timeFrame: During the two experimental sessions, at day 1 and up to day 15
measure: Change in brain activity (as measured by EEG - connectivity) between neuromodulations
timeFrame: During the two experimental sessions, at day 1 and up to day 15
Other outcomes:
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