Print Email Facebook Twitter Electrical vestibular stimuli to enhance vestibulo-motor output and improve subject comfort Title Electrical vestibular stimuli to enhance vestibulo-motor output and improve subject comfort Author Forbes, P.A. Dakin, C.J. Geers, A.M. Vlaar, M.P. Happee, R. Siegmund, G.P. Schouten, A.C. Blouin, J.S. Faculty Mechanical, Maritime and Materials Engineering Department Biomechanical Engineering Date 2014-01-02 Abstract Electrical vestibular stimulation is often used to assess vestibulo-motor and postural responses in both clinical and research settings. Stochastic vestibular stimulation (SVS) is a recently established technique with many advantages over its square-wave counterpart; however, the evoked muscle responses remain relatively small. Although the vestibular-evoked responses can be enhanced by increasing the stimulus amplitude, subjects often perceive these higher intensity electrical stimuli as noxious or painful. Here, we developed multisine vestibular stimulation (MVS) signals that include precise frequency contributions to increase signal-to-noise ratios (SNR) of stimulus-evoked muscle and motor responses. Subjects were exposed to three different MVS stimuli to establish that: 1) MVS signals evoke equivalent vestibulo-motor responses compared to SVS while improving subject comfort and reducing experimentation time, 2) stimulus-evoked vestibulo-motor responses are reliably estimated as a linear system and 3) specific components of the cumulant density time domain vestibulo-motor responses can be targeted by controlling the frequency content of the input stimulus. Our results revealed that in comparison to SVS, MVS signals increased the SNR 3-6 times, reduced the minimum experimentation time by 85% and improved subjective measures of comfort by 20-80%. Vestibulo-motor responses measured using both EMG and force were not substantially affected by nonlinear distortions. In addition, by limiting the contribution of high frequencies within the MVS input stimulus, the magnitude of the medium latency time domain motor output response was increased by 58%. These results demonstrate that MVS stimuli can be designed to target and enhance vestibulo-motor output responses while simultaneously improving subject comfort, which should prove beneficial for both research and clinical applications. To reference this document use: http://resolver.tudelft.nl/uuid:c1c0ceb5-5853-4ba2-9ab1-76ea19e015e6 DOI https://doi.org/10.1371/journal.pone.0084385 Publisher Public Library of Science ISSN 1932-6203 Source PLoS One, 9 (1), 2014 Part of collection Institutional Repository Document type journal article Rights (c) 2014 The Author(s)This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Files PDF Forbes_2014.pdf 478.1 KB Close viewer /islandora/object/uuid:c1c0ceb5-5853-4ba2-9ab1-76ea19e015e6/datastream/OBJ/view