The effect of EMG magnitude on the masseter vestibular evoked myogenic potential(mVEMP)  

作　　者：Daniel J.Romero Gary P.Jacobson Richard A.Roberts 

机构地区：[1]Department of Hearing and Speech Sciences,Division of Vestibular Sciences,Vanderbilt University Medical Center,121521st Ave.South,6308 Medical Center East,Nashville,TN,37232-8718,USA

出　　处：《Journal of Otology》2022年第4期203-210,共8页中华耳科学杂志（英文版）

摘　　要：Introduction:The masseter vestibular evoked myogenic potential(mVEMP)is a bilaterally generated,electromyographically(EMG)-mediated response innervated by the trigeminal nerve.The purpose of the present investigation was to 1)determine whether subjects could accurately achieve and maintain a range of EMG target levels,2)to examine the effects of varied EMG levels on the latencies and amplitudes of the mVEMP,and 3)to investigate the degree of side-to-side asymmetry and any effects of EMG activation.Methods:Subjects were nine neurologically and otologically normal young adults.A high-intensity tone burst was presented monaurally while subjects were seated upright and asked to match a range of EMG target levels by clenching their teeth.Recordings were made from the ipsilateral and contralateral masseter muscles referenced to the ear being monaurally stimulated.Results:We found that the tonic EMG target had no effect on mVEMP latency.Additionally,although mVEMP amplitudes“scaled”to the EMG target,there was a tendency for the subjects’EMG level to“undershoot”the EMG target levels greater than 50 mV.While some individuals did generate differences in EMG activation between sides,there were no significant differences on average EMG activation between sides.Further,while average corrected amplitude asymmetry was similar across EMG targets,some individuals demonstrated large,corrected amplitude asymmetry ratios.Conclusions:The results of this investigation suggest that,as with cVEMP recordings,the underlying EMG activation may vary between subjects and could impact mVEMP amplitudes,yet could be mitigated by amplitude correction techniques.Further it is important to be aware that even young normal subjects have difficulty maintaining large,tonic EMG activity during the mVEMP recording.

关 键 词：Vestibular evoked myogenic potentials (VEMPs) Masseter VEMPs Electromyography(EMG) Vestibulomasseteric reflex(VMR) EMG target Level 

分 类 号：R764[医药卫生—耳鼻咽喉科]