S Kammermeier1, A Singh2, S Noachtar3, I Krotofil3, K Bötzel3. 1. Klinikum der Universität München, Neurologische Klinik und Poliklinik, Marchioninistraße 15, 81377 München, Germany. Electronic address: stefan.kammermeier@med.uni-muenchen.de. 2. Klinikum der Universität München, Neurologische Klinik und Poliklinik, Marchioninistraße 15, 81377 München, Germany; Yerkes National Primate Research Center, Neuroscience Building, Emory University, 954 Gatewood Rd NE, Atlanta, GA 30329, USA. 3. Klinikum der Universität München, Neurologische Klinik und Poliklinik, Marchioninistraße 15, 81377 München, Germany.
Abstract
OBJECTIVE: Loud acoustic stimuli at 500Hz activate the vestibular system. Intermediate-latency vestibular cortical potentials of multimodal cortex regions were investigated, beyond the 20ms time range. METHODS: Eighteen healthy subjects with 32-channel EEG and one epilepsy patient with right-sided intracortical electrodes received three types of stimuli: tone bursts capable of evoking vestibular evoked myogenic potentials (VEMP) in neck muscles and sham stimuli matched for either frequency or amplitude, which cannot evoke myogenic responses. RESULTS: VEMP-capable stimuli activated anterior insula and posterior operculum bilaterally at 20, 30, 60 and 110ms, frontal brain regions at 70 and 110ms, determined by Brain Evoked Source Analysis BESA. Recordings from intracranial electrodes revealed corresponding peaks at identical latencies. Stimulus-locked high and low beta and mu band modulations were found in vestibular, parietal and occipital regions, beyond 20ms. Sham stimuli only evoked late acoustic potentials. Corresponding vestibular potentials were also seen in an eight-channel bipolar Laplacian montage. CONCLUSIONS: The sequentially appearing cortical potentials evoked by VEMP-capable stimuli co-locate with data from functional imaging studies. Frequency-specific activity (induced potentials) in these areas may reflect multimodal proprioceptive and visual sensory crosstalk. SIGNIFICANCE: Vestibular cortical evoked potentials may see clinical use in vertigo disorders.
OBJECTIVE: Loud acoustic stimuli at 500Hz activate the vestibular system. Intermediate-latency vestibular cortical potentials of multimodal cortex regions were investigated, beyond the 20ms time range. METHODS: Eighteen healthy subjects with 32-channel EEG and one epilepsypatient with right-sided intracortical electrodes received three types of stimuli: tone bursts capable of evoking vestibular evoked myogenic potentials (VEMP) in neck muscles and sham stimuli matched for either frequency or amplitude, which cannot evoke myogenic responses. RESULTS: VEMP-capable stimuli activated anterior insula and posterior operculum bilaterally at 20, 30, 60 and 110ms, frontal brain regions at 70 and 110ms, determined by Brain Evoked Source Analysis BESA. Recordings from intracranial electrodes revealed corresponding peaks at identical latencies. Stimulus-locked high and low beta and mu band modulations were found in vestibular, parietal and occipital regions, beyond 20ms. Sham stimuli only evoked late acoustic potentials. Corresponding vestibular potentials were also seen in an eight-channel bipolar Laplacian montage. CONCLUSIONS: The sequentially appearing cortical potentials evoked by VEMP-capable stimuli co-locate with data from functional imaging studies. Frequency-specific activity (induced potentials) in these areas may reflect multimodal proprioceptive and visual sensory crosstalk. SIGNIFICANCE: Vestibular cortical evoked potentials may see clinical use in vertigo disorders.
Authors: Robin T Bigelow; Yevgeniy R Semenov; Carolina Trevino; Luigi Ferrucci; Susan M Resnick; Eleanor M Simonsick; Qian-Li Xue; Yuri Agrawal Journal: J Am Geriatr Soc Date: 2015-08-27 Impact factor: 5.562