Raufer Stefan, Verhulst Sarah
Dept. of Medical Physics and Acoustics, Carl von Ossietzky University Oldenburg, 26129 Oldenburg, Germany.
Dept. of Medical Physics and Acoustics, Carl von Ossietzky University Oldenburg, 26129 Oldenburg, Germany.
Hear Res. 2016 Dec;342:150-160. doi: 10.1016/j.heares.2016.10.016. Epub 2016 Oct 27.
This study describes a method based on temporal suppression of click-evoked otoacoustic emissions (CEOAEs) to estimate the time course and duration of human basilar membrane impulse responses (BM IRs). This was achieved by tracing the suppression of dominant peaks in the CEOAE spectrum as a function of the temporal separation between two equal-level stimulus clicks. The relationship between the suppression pattern and underlying BM IR duration near the generation site of the CEOAE frequency was established using model simulations. To relate BM IR duration estimates to cochlear filter tuning (Q), a tuning ratio was derived from available BM IR measurements in animals. Results for 11 normal-hearing subjects yielded BM IR duration estimates of 37.4/F ms at 65 dB peSPL and 36.4/F ms at 71 dB peSPL, with F in kHz. Corresponding Q estimates were 14.2F[in kHz] at 65 dB peSPL and 13.8F[in kHz] at 71 dB peSPL. Because the proposed temporal suppression method relies on cochlear nonlinearity, the method is applicable for stimulus levels above 30-40 dB SPL and complements existing OAE methods to assess human cochlear filter tuning.
本研究描述了一种基于对点击诱发耳声发射（CEOAEs）进行时间抑制的方法，以估计人类基底膜冲动响应（BM IRs）的时间进程和持续时间。这是通过追踪CEOAEs频谱中主峰的抑制情况，作为两个等强度刺激点击之间时间间隔的函数来实现的。利用模型模拟建立了抑制模式与CEOAEs频率产生部位附近潜在BM IR持续时间之间的关系。为了将BM IR持续时间估计值与耳蜗滤波器调谐（Q）相关联，从动物现有的BM IR测量中得出了一个调谐比率。11名正常听力受试者的结果显示，在65 dB peSPL时，BM IR持续时间估计值为37.4/F ms，在71 dB peSPL时为36.4/F ms，其中F的单位为kHz。相应的Q估计值在65 dB peSPL时为14.2F[单位为kHz]，在71 dB peSPL时为13.8F[单位为kHz]。由于所提出的时间抑制方法依赖于耳蜗非线性，该方法适用于高于30 - 40 dB SPL的刺激水平，并补充了现有的耳声发射方法来评估人类耳蜗滤波器调谐。
