Department of Biomedical Engineering, Southern University of Science and Technology, Shenzhen, Guangdong 518055, China.
Oregon Hearing Research Center, Department of Otolaryngology and Head and Neck Surgery, Oregon Health and Science University, Portland, OR 97239, USA.
Neural Plast. 2018 Jul 17;2018:7502648. doi: 10.1155/2018/7502648. eCollection 2018.
The discovery that an apparent forward-propagating otoacoustic emission (OAE) induced basilar membrane vibration has created a serious debate in the field of cochlear mechanics. The traditional theory predicts that OAE will propagate to the ear canal via a backward traveling wave on the basilar membrane, while the opponent theory proposed that the OAE will reach the ear canal via a compression wave. Although accepted by most people, the basic phenomenon of the backward traveling wave theory has not been experimentally demonstrated. In this study, for the first time, we showed the backward traveling wave by measuring the phase spectra of the basilar membrane vibration at multiple longitudinal locations of the basal turn of the cochlea. A local vibration source with a unique and precise location on the cochlear partition was created to avoid the ambiguity of the vibration source in most previous studies. We also measured the vibration pattern at different places of a mechanical cochlear model. A slow backward traveling wave pattern was demonstrated by the time-domain sequence of the measured data. In addition to the wave propagation study, a transmission line mathematical model was used to interpret why no tonotopicity was observed in the backward traveling wave.
一种明显的向前传播的耳声发射（OAE）诱导基底膜振动的发现，在耳蜗力学领域引发了一场激烈的争论。传统理论预测 OAE 将通过基底膜上的反向行波传播到耳道，而对立理论则提出 OAE 将通过压缩波到达耳道。尽管这一理论被大多数人接受，但反向行波理论的基本现象尚未得到实验证明。在这项研究中，我们首次通过测量耳蜗底部基底回多个纵向位置的基底膜振动的相位谱，展示了反向行波。通过在耳蜗隔板上创建一个具有独特且精确位置的局部振动源，避免了大多数先前研究中振动源的模糊性。我们还测量了机械耳蜗模型中不同位置的振动模式。通过测量数据的时域序列，证明了一种缓慢的反向行波模式。除了波传播研究，还使用传输线数学模型解释了为什么在反向行波中观察不到音位特异性。
