Department of Otolaryngology, Hannover Medical School, Cluster of Excellence Hearing4all, Carl-Neuberg-Straße 1, 30625 Hannover, Germany.
J Acoust Soc Am. 2020 Feb;147(2):1147. doi: 10.1121/10.0000744.
In cochlear implant (CI) users with residual hearing, the electrode-nerve interface can be investigated combining electric-acoustic stimulation (EAS) via electrocochleography (ECochG), a technique to record cochlear potentials evoked by acoustic stimulation. EAS interaction was shown in previous studies using psychoacoustic experiments. This work characterizes EAS interaction through psychophysical experiments and the amplitude growth of cochlear microphonics (CM) and auditory nerve neurophonics (ANN) derived from intracochlear ECochG recordings. Significant CM responses were recorded at psychoacoustic threshold levels. The mean difference between psychoacoustic and CM threshold was 17.5 dB. No significant ANN responses were recorded at the psychoacoustic threshold level. At the psychoacoustic most comfortable level, significant CM and ANN responses were recorded. In the presence of electrical stimulation, the psychoacoustic detection thresholds were elevated on average by 2.38 dB while the recorded CM amplitudes were attenuated on average by 1.15 dB. No significant differences in electrophysiological EAS interaction across acoustic stimulation levels were observed from CM recordings. The presence of psychophysical and electrophysiological EAS interaction demonstrates that some aspects of psychoacoustic EAS interaction can be measured via intracochlear ECochG.
在具有残余听力的人工耳蜗（CI）使用者中，可以通过电声刺激（EAS）结合电 Cochleography（ECochG）来研究电极-神经界面，ECochG 是一种记录由声刺激引起的耳蜗电位的技术。在以前的研究中，已经使用心理声学实验显示了 EAS 的相互作用。本工作通过心理物理实验以及源自耳蜗内 ECochG 记录的耳蜗微音（CM）和听神经神经音（ANN）的幅度增长来描述 EAS 相互作用。在心理物理阈值水平记录到了显著的 CM 反应。心理物理阈值与 CM 阈值之间的平均差异为 17.5dB。在心理声学阈值水平未记录到显著的 ANN 反应。在心理声学最舒适水平下，记录到了显著的 CM 和 ANN 反应。在电刺激存在的情况下，平均而言，心理声学检测阈值升高了 2.38dB，而记录的 CM 幅度平均衰减了 1.15dB。从 CM 记录中观察到，电生理 EAS 相互作用在声刺激水平上没有显著差异。心理物理和电生理 EAS 相互作用的存在表明，通过耳蜗内 ECochG 可以测量一些心理声学 EAS 相互作用的方面。
