Prince of Wales Clinical School and Neuroscience Research Australia, University of New South Wales, Randwick, Sydney, New South Wales, Australia.
Prince of Wales Clinical School and Neuroscience Research Australia, University of New South Wales, Randwick, Sydney, New South Wales, Australia
J Appl Physiol (1985). 2017 Jun 1;122(6):1470-1484. doi: 10.1152/japplphysiol.01069.2016. Epub 2017 Mar 23.
We have investigated the effectiveness of two bone-conducted (BC) stimuli in producing vestibular evoked myogenic potentials (VEMPs) following stimulation along midsagittal skull sites. Twenty subjects (mean age 24 yr, range: 18-34 yr; 6 men; 14 women) were studied using a smoothed impulse and a 500-Hz tone burst applied to Nz, Fpz, AFz, Fz, FCz, and Cz with both compressive and rarefactive onset phases. Cervical (cVEMPs) and ocular VEMPs (oVEMPs) were recorded as well as linear acceleration in three axes. cVEMPs evoked by 500 Hz showed no change in response polarity to either stimulus location or phase. cVEMPs evoked by the impulsive stimulus showed larger initial peak amplitudes at AFz and Fz using compressive stimuli and differences in initial peak latency between the two phases. In contrast, amplitude, latency, and response polarity for oVEMPs were markedly affected by stimulus location and phase, which were similar for both BC stimuli, with little correlation with induced acceleration of the head. Latencies were earliest at AFz and Fz where compressive onset stimuli evoked an initial negativity (average latency 8.6-11.0 ms). At other sites compressive onset stimuli usually evoked oVEMPs with an initial positivity. We conclude that both 500 Hz and impulsive stimuli are effective means of evoking cVEMPs and oVEMPs from mid sagittal skull sites. The effects depend upon both location and phase and differ for oVEMPs and cVEMPs. Initial negativities for oVEMPs following compressive stimuli were most consistently obtained using the AFz and Fz sites. We investigated the effect of stimulus location and phase (compressive and rarefactive) in the midsagittal plane for the cVEMP and oVEMP evoked by bone-conducted (BC) 500 Hz and BC impulsive stimuli. For cVEMPs, location effects were limited but were observed for BC impulses. For oVEMPs, both stimuli affected amplitude, latency, and polarity, depending on stimulus location and phase. Compressive stimuli at Fz and AFz evoked early negative oVEMPs most reliably.
我们研究了两种骨导（BC）刺激在刺激中颅矢状位后产生前庭诱发肌源性电位（VEMPs）的效果。 20 名受试者（平均年龄 24 岁，范围：18-34 岁；6 名男性；14 名女性）使用平滑脉冲和 500Hz 声爆发刺激 Nz、Fpz、AFz、Fz、FCz 和 Cz，同时具有压缩和稀疏起始相。记录了颈性（cVEMPs）和眼性 VEMPs（oVEMPs）以及三个轴线上的线性加速度。 500Hz 产生的 cVEMPs 对刺激位置或相位的反应极性没有变化。冲动刺激产生的 cVEMPs 在使用压缩刺激时，在 AFz 和 Fz 处的初始峰值幅度较大，并且在两个相位之间存在初始峰值潜伏期的差异。相比之下，oVEMPs 的幅度、潜伏期和反应极性受刺激位置和相位的显著影响，这两种 BC 刺激相似，与头部感应加速度相关性小。潜伏期在 AFz 和 Fz 处最早，其中压缩起始刺激会引起初始负性（平均潜伏期 8.6-11.0ms）。在其他部位，压缩起始刺激通常会引起 oVEMPs 的初始正性。我们得出结论，500Hz 和冲动刺激都是从中颅矢状位刺激产生 cVEMPs 和 oVEMPs 的有效方法。这些效果取决于位置和相位，并且 oVEMPs 和 cVEMPs 不同。在使用 AFz 和 Fz 部位时，最一致地获得了压缩刺激后 oVEMPs 的初始负性。我们研究了刺激位置和相位（压缩和稀疏）在中颅矢状面的影响，用于骨导（BC）500Hz 和 BC 冲动刺激引起的 cVEMP 和 oVEMP。对于 cVEMPs，位置效应是有限的，但在 BC 脉冲中观察到了位置效应。对于 oVEMPs，两种刺激都根据刺激位置和相位影响幅度、潜伏期和极性。在 Fz 和 AFz 处的压缩刺激最可靠地引起早期负性 oVEMPs。
