NCT05198440

Neuromodulation of Motion Illusions (Vection)

• Status: Unknown
• Phase: N/A
• Study type: Interventional
• Enrollment: 90 (estimated)
• Sponsor: University Hospital, Grenoble · Academic / Other
• Sex: All
• Age: 18 Years – 40 Years
• Healthy volunteers: Accepted

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)).

Conditions

• Healthy

Interventions

Type	Name	Description
DEVICE	non-invasive neuromodulation	The modulations of the vection phenomenon will then be studied over two sessions of 1h30, separated by a minimum of 3 to a maximum of 15 days (the first session will be performed following the MRI). Each session will include: the installation of an EEG headset and the parameterization of the stimulation (30 min), then a phase of recording of the vection with neuromodulation (1h) according to 2 experimental conditions: * Experiment 1: recording of vection at rest (20 min), then during and after neurostimulation by tES (20 min). Active and sham (placebo) stimulation will be tested separately during the two sessions (counterbalanced order). * Experiment 2: recording of vection during neuromodulation by rTMS triggered in real time (1h). Triggering will be based on behavioral response (experiment 2a) or oscillatory activity detection (experiment 2b). Active and sham (placebo) stimulation will be tested in both sessions (randomized order).
DEVICE	electroencephalography	The modulations of the vection phenomenon will then be studied over two sessions of 1h30, separated by a minimum of 3 to a maximum of 15 days (the first session will be performed following the MRI). Each session will include: the installation of an EEG headset and the parameterization of the stimulation (30 min), then a phase of recording of the vection with neuromodulation (1h) according to 2 experimental conditions: * Experiment 1: recording of vection at rest (20 min), then during and after neurostimulation by tES (20 min). Active and sham (placebo) stimulation will be tested separately during the two sessions (counterbalanced order). * Experiment 2: recording of vection during neuromodulation by rTMS triggered in real time (1h). Triggering will be based on behavioral response (experiment 2a) or oscillatory activity detection (experiment 2b). Active and sham (placebo) stimulation will be tested in both sessions (randomized order).
DEVICE	anatomical MRI	The modulations of the vection phenomenon will then be studied over two sessions of 1h30, separated by a minimum of 3 to a maximum of 15 days (the first session will be performed following the MRI). Each session will include: the installation of an EEG headset and the parameterization of the stimulation (30 min), then a phase of recording of the vection with neuromodulation (1h) according to 2 experimental conditions: * Experiment 1: recording of vection at rest (20 min), then during and after neurostimulation by tES (20 min). Active and sham (placebo) stimulation will be tested separately during the two sessions (counterbalanced order). * Experiment 2: recording of vection during neuromodulation by rTMS triggered in real time (1h). Triggering will be based on behavioral response (experiment 2a) or oscillatory activity detection (experiment 2b). Active and sham (placebo) stimulation will be tested in both sessions (randomized order).

Timeline

• Start date: 2022-01-30
• Primary completion: 2024-01-30
• Completion: 2024-01-30
• First posted: 2022-01-20
• Last updated: 2022-01-20