Vestibular Stimulation during a Simple Centrifuge Run.

AbstractA single-blind study to investigate the effects of noisy galvanic vestibular stimulation (nGVS) in straight walking and 2 Hz head yaw walking for healthy and bilateral vestibular hypofunction (BVH) participants in light and dark conditions. The optimal stimulation intensity for each participant was determined by calculating standing stability on a force plate while randomly applying six graded nGVS intensities (0–1000 µA). The chest–pelvic (C/P) ratio and lateral deviation of the center of mass (COM) were measured by motion capture during straight and 2 Hz head yaw walking in light and dark conditions. Participants were blinded to nGVS served randomly and imperceivably. Ten BVH patients and 16 healthy participants completed all trials. In the light condition, the COM lateral deviation significantly decreased only in straight walking (p = 0.037) with nGVS for the BVH. In the dark condition, both healthy (p = 0.026) and BVH (p = 0.017) exhibited decreased lateral deviation during nGVS. The C/P ratio decreased significantly in BVH for 2 Hz head yaw walking with nGVS (p = 0.005) in light conditions. This study demonstrated that nGVS effectively reduced walking deviations, especially in visual deprived condition for the BVH. Applying nGVS with different head rotation frequencies and light exposure levels may accelerate the rehabilitation process for patients with BVH.Clinical Trial Registration This clinical trial was prospectively registered at www.clinicaltrials.gov with the Unique identifier: NCT03554941. Date of registration: (13/06/2018).

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Qualitative and quantitative assessment of magnetic vestibular stimulation in humans

Journal of Vestibular Research ◽

10.3233/ves-201538 ◽

2020 ◽

Vol 30 (6) ◽

pp. 353-361

Author(s):

Rebecca S. Dewey ◽

Rachel Gomez ◽

Chris Degg ◽

David M. Baguley ◽

Paul M. Glover

Keyword(s):

Magnetic Field ◽

Objective Measure ◽

Quantitative Measure ◽

Vestibular Stimulation ◽

Initial Study ◽

Clinical Test ◽

Healthy Control ◽

Student’S T ◽

The Impact ◽

The Magnetic Field

The sensation of phantom motion or exhibition of bodily sway is often reported in the proximity of an MR scanner. It is proposed that the magnetic field stimulates the vestibular system. There are a number of possible mechanisms responsible, and the relative contributions of susceptibility on the otolithic receptors and the Lorentz force on the cupulae have not yet been explored. This exploratory study aims to investigate the impact of being in the proximity of a 7.0 T MR scanner. The modified clinical test of sensory interaction on balance (mCTSIB) was used to qualitatively ascertain whether or not healthy control subjects who passed the mCTSIB in normal conditions 1) experienced subjective sensations of dizziness, vertigo or of leaning or shifting in gravity when in the magnetic field and 2) exhibited visibly increased bodily sway whilst in the magnetic field compared to outside the magnetic field. Condition IV of the mCTSIB was video recorded outside and inside the magnetic field, providing a semi-quantitative measure of sway. For condition IV of the mCTSIB (visual and proprioceptive cues compromised), all seven locations/orientations around the scanner yielded significantly more sway than at baseline (p < 0.01 FDR). A Student’s t-test comparing the RMS velocity of a motion marker on the upper arm during mCTSIB condition IV showed a significant increase in the amount of motion exhibited in the field (T = 2.59; d.f. = 9; p = 0.029) compared to outside the field. This initial study using qualitative measures of sway demonstrates that there is evidence for MR-naïve individuals exhibiting greater sway while performing the mCTSIB in the magnetic field compared to outside the field. Directional polarity of sway was not significant. Future studies of vestibular stimulation by magnetic fields would benefit from the development of a sensitive, objective measure of balance function, which can be performed inside a magnetic field.

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Derealization and motion-perception related to repeated exposure to 3T Magnetic Resonance Image scanner in healthy adults

Journal of Vestibular Research ◽

10.3233/ves-201577 ◽

2020 ◽

pp. 1-12

Author(s):

Sergio Martínez-Gallardo ◽

José A. Miguel-Puga ◽

Davis Cooper-Bribiesca ◽

Adolfo M. Bronstein ◽

Kathrine Jáuregui-Renaud

Keyword(s):

Magnetic Resonance ◽

Motion Perception ◽

State Anxiety ◽

Random Order ◽

Vestibular Stimulation ◽

Psychological Effects ◽

Psychological Reactions ◽

Exposure Effect ◽

Individual Susceptibility ◽

Magnetic Exposure

BACKGROUND: Magnetic Resonance Imaging (MRI) scanning can induce psychological effects. No studies have investigated the role of magnetic vestibular stimulation (MVS) in 3TMRI scanner-induced psychological reactions. OBJECTIVE: To assess depersonalization/derealization(DD), state anxiety and motion-perception in a 3TMRI scanner, acutely and long-term. PARTICIPANTS: 48 healthcare professionals and students were included, after preliminary rejection of claustrophobes and neuro-otology and psychiatry assessments. PROCEDURES: Participants completed questionnaires on personal habits, dissociation, anxiety/depression and motion sickness susceptibility. Validated DD and state anxiety questionnaires were administered before and after magnetic exposure twice, entering the bore head and feet first in random order, one week apart. During the following week, dizziness/disorientation was reported daily. One month later, 11 subjects repeated the procedure to assess reproducibility. RESULTS: Considerable individual susceptibility was observed, circa 40% of the subjects reported self-motion perception related to the exposure, with variable increase on DD symptoms. Multivariate analysis showed that DD scores after any exposure were influenced by entering the bore “feet first”, motion-perception, and the mean sleep hours/week (MANCOVA, R = 0.58, p = 0.00001). There was no clear effect of scanner exposure on state anxiety, which was related to trait anxiey but not to DD scores. During repeated exposures, about half of all subjects re-entering the scan reported motion-perception, but DD or anxiety symptoms were not consistent. CONCLUSION: Psychological effects during 3TMRI scanning result from multiple, interacting factors, including novelty of the procedure (first-exposure effect), motion-perception due to MVS, head/body orientation, sleeping habits and individual susceptibility. Forewarning subjects of these predisposing factors may increase tolerance to MRI scanning.

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Effects of caloric vestibular stimulation on serotoninergic system in the media vestibular nuclei of guinea pigs

Chinese Medical Journal ◽

10.1097/00029330-200701020-00009 ◽

2007 ◽

Vol 120 (2) ◽

pp. 120-124 ◽

Cited By ~ 5

Author(s):

Fu-rong MA ◽

Jun-xiu LIU ◽

Xue-pei LI ◽

Jian-jun MAO ◽

Qun-dan ZHANG ◽

...

Keyword(s):

Guinea Pigs ◽

Vestibular Nuclei ◽

Vestibular Stimulation ◽

Serotoninergic System ◽

Caloric Vestibular Stimulation ◽

The Media

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No evidence for after-effects of noisy galvanic vestibular stimulation on motion perception

Scientific Reports ◽

10.1038/s41598-020-59374-9 ◽

2020 ◽

Vol 10 (1) ◽

Cited By ~ 4

Author(s):

Aram Keywan ◽

Hiba Badarna ◽

Klaus Jahn ◽

Max Wuehr

Keyword(s):

Motion Perception ◽

Vestibular Stimulation ◽

Galvanic Vestibular Stimulation ◽

After Effects

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Vestibular Influence on Human Auditory Space Perception

Journal of Neurophysiology ◽

10.1152/jn.2000.84.2.1107 ◽

2000 ◽

Vol 84 (2) ◽

pp. 1107-1111 ◽

Cited By ~ 33

Author(s):

Jörg Lewald ◽

Hans-Otto Karnath

Keyword(s):

Cold Water ◽

Human Subjects ◽

Space Perception ◽

Median Plane ◽

Vestibular Stimulation ◽

Whole Body ◽

Interaural Level Difference ◽

Auditory Periphery ◽

Auditory Space ◽

Sound Image

We investigated the effect of vestibular stimulation on the lateralization of dichotic sound by cold-water irrigation of the external auditory canal in human subjects. Subjects adjusted the interaural level difference of the auditory stimulus to the subjective median plane of the head. In those subjects in whom dizziness and nystagmus indicated sufficient vestibular stimulation, these adjustments were significantly shifted toward the cooled ear compared with the control condition (irrigation with water at body temperature); i.e., vestibular stimulation induced a shift of the sound image toward the nonstimulated side. The mean magnitude of the shift was 7.3 dB immediately after vestibular stimulation and decreased to 2.5 dB after 5 min. As shown by an additional control experiment, this effect cannot be attributed to a unilateral hearing loss induced by cooling of the auditory periphery. The results indicate the involvement of vestibular afferent information in the perception of sound location during movements of the head and/or the whole body. We thus hypothesize that vestibular information is used by central-nervous mechanisms generating a world-centered representation of auditory space.

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