Original Research ARTICLE
Noisy galvanic stimulation improves vestibular perception
- 1German Center for Vertigo and Balance Disorders (DSGZ) , LMU Munich, Germany
- 2Neurology, Schön Klinik, Germany
It has recently been demonstrated that noisy galvanic vestibular stimulation (nGVS) delivered as imperceptible white noise can improve balance control via the induction of stochastic resonance. However, it is unclear whether these balance improvements are accompanied by simultaneous enhancement to vestibular motion perception. In this study, 15 healthy subjects performed eight quiet-stance tasks on foam with eyes closed at eight different nGVS amplitudes ranging from 0mA (baseline) to 0.5mA. The nGVS amplitude that improved balance performance most compared to baseline was assigned as the optimal nGVS amplitude. For 13 out of 15 subjects an optimal nGVS could be determined, and therefore were included in the subsequent experimental procedures. The effect of nGVS delivered at the determined optimal intensity on vestibular perceptual thresholds was examined using direction-recognition tasks on a motion-platform, testing roll rotations at 0.2, 0.5 and 1.0Hz, both with active and sham nGVS stimulations. nGVS significantly reduced direction recognition thresholds compared to the sham condition at 0.5Hz and 1.0Hz, whilst no significant effect of nGVS was found at 0.2Hz. Interestingly, no correlation was found between nGVS-induced improvements in balance control and vestibular motion perception at 0.5 and 1Hz, which may suggest different mechanisms by which nGVS affects both modalities. For the first time, we show that nGVS can enhance roll vestibular motion perception. The outcomes of this study are likely to be relevant for the potential therapeutic use of nGVS in patients with balance problems.
Keywords: vestibular motion perception, Noisy galvanic stimulation, stochastic resonance, Vertigo, Balance control
Received: 04 Dec 2017;
Accepted: 06 Feb 2018.
Edited by:Raymond Van De Berg, Maastricht University Medical Centre, Netherlands
Reviewed by:Christopher McCrum, Maastricht University, Netherlands
Ann Hallemans, University of Antwerp, Belgium
Copyright: © 2018 Keywan, Wuehr, Pradhan and Jahn. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
* Correspondence: Mr. Aram Keywan, German Center for Vertigo and Balance Disorders (DSGZ) , LMU Munich, Munich, Germany, email@example.com