Department of Otolaryngology and Communicative Sciences, University of Mississippi Medical Center, 2500 North State Street, Jackson, MS 39216, USA.
J Otolaryngol Head Neck Surg. 2010 Oct;39(5):491-7.
In this cross-sectional study, we investigated the frequency tuning properties of sound-evoked vestibular myogenic potentials in extraocular muscles (OVEMPs) in normal human subjects.
Acoustic tone bursts (130 dB pSPL, 10 ms plateau, 1 ms rise/fall) with nine frequencies from 125 to 4000 Hz were presented monoaurally to 12 normal subjects while they sat upright and maintained centre gaze. Using surface electrodes, the OVEMPs were recorded at four locations surrounding the contralateral eye (superior, inferior, nasal, and temporal) and were referenced to an electrode placed at the nape of the neck over C7. To measure the amplitudes of the OVEMP, signals from the electrodes were amplified and sampled at 10 kHz and were averaged over 250 repetitions.
We found that the OVEMPs recorded at the four sites exhibited similar well-defined frequency tuning with peak amplitude at ≈ 1000 Hz.
Although several studies have examined the frequency tuning of the vestibular evoked myogenic potential measured from the sternocleidomastoid muscles (SVEMP), the reported results are quite variable as regards frequency, which produces peak amplitude. The well-defined OVEMP frequency tuning provides an alternative to the SVEMP for assessing vestibular function via acoustic stimulation. Further studies are needed to identify the extent to which each of the five vestibular end-organs is activated by sound and their contribution to the sound-evoked vestibular myogenic potentials.
在这项横断面研究中，我们调查了正常人体中外展肌声诱发前庭肌源性电位（OVEMP）的频率调谐特性。
使用单耳向 12 名正常受试者呈现 9 个频率（125-4000 Hz）的声刺激（130 dB pSPL，10 ms 平台，1 ms 上升/下降），受试者坐直并保持中心注视。使用表面电极，在对侧眼周围的四个位置（上、下、鼻和颞）记录 OVEMP，并以 C7 上方颈后的一个电极参考。为了测量 OVEMP 的幅度，将来自电极的信号放大并以 10 kHz 的频率采样，并在 250 次重复中进行平均。
我们发现，在四个部位记录的 OVEMP 表现出相似的明确定义的频率调谐，峰值幅度约为 1000 Hz。
尽管已有几项研究检查了从胸锁乳突肌（SVEMP）测量的前庭诱发肌源性电位的频率调谐，但关于产生峰值幅度的频率的报道结果差异很大。明确的 OVEMP 频率调谐为通过声学刺激评估前庭功能提供了一种替代 SVEMP 的方法。需要进一步的研究来确定每个五个前庭终器在多大程度上被声音激活以及它们对声音诱发的前庭肌源性电位的贡献。
