Kato T, Shiraishi K, Eura Y, Shibata K, Sakata T, Morizono T, Soda T
Department of Otorhinolaryngology, School of Medicine, Fukuoka University, Japan.
Audiol Neurootol. 1998 Jul-Aug;3(4):253-64. doi: 10.1159/000013797.
A large negative deflection with a latency of 3 ms was observed in the auditory brainstem response (ABR) waveforms of some patients with peripheral profound deafness. This deflection was termed the N3 potential. In this paper, we review patients with the N3 potential and discuss the characteristics of abnormal ABR waveforms. The origin of the N3 potential was also discussed, especially with respect to vestibular evoked potentials. In most of the patients, audiograms showed no response to the maximum output of an audiometer in the high-frequency range and a residual response in the low-frequency range. The N3 potentials were noted at intensities of 80 dB nHL or greater. As the stimulus intensity increased, the amplitude of the potential increased and the latency decreased. A high repetition rate (83.3/s) of the click stimulus influenced the latency and amplitude of the N3 potential. The potential was replicated on retest within less than a month, and had a consistent latency and amplitude over the scalp. The results indicate that the N3 potential is not an electrical artifact but a physiological neural response evoked by a loud sound. The N3 potential is most likely not an auditory evoked response from cochlear or a response from a semicircular canal, because it has a 3-ms latency, a sharp waveform, and is unassociated with vertigo. The results suggest that the N3 potential may be a saccular acoustic response.
在一些极重度感音神经性聋患者的听觉脑干反应（ABR）波形中观察到潜伏期为3毫秒的大负向波。这个波被称为N3波。在本文中，我们回顾了有N3波的患者，并讨论了异常ABR波形的特征。我们还讨论了N3波的起源，特别是关于前庭诱发电位方面。在大多数患者中，听力图显示在高频范围内对听力计的最大输出无反应，而在低频范围内有残余反应。N3波在强度为80 dB nHL或更高时被记录到。随着刺激强度增加，该波的波幅增大且潜伏期缩短。短声刺激的高重复率（83.3/s）影响N3波的潜伏期和波幅。该波在不到一个月的复测中可重复出现，且在头皮上具有一致的潜伏期和波幅。结果表明，N3波不是电伪迹，而是由强声诱发的生理性神经反应。N3波很可能不是来自耳蜗的听觉诱发电位，也不是来自半规管的反应，因为它有3毫秒的潜伏期、尖锐的波形，且与眩晕无关。结果提示，N3波可能是球囊听觉反应。
