Fast Reverse Propagation of Sound in the Living Cochlea
Fast Reverse Propagation of Sound in the Living Cochlea
复制标题
DOI：
10.1016/j.bpj.2010.03.003
复制
发表时间：
2010-06-02
影响因子：
3.4
通讯作者：
Ren, Tianying
中科院分区：
文献类型：
--
作者：
He, Wenxuan;Fridberger, Anders;Ren, Tianying
听觉器官耳蜗不仅能检测声音，还能发出声音。这种声音，耳声发射，被广泛用于诊断听力障碍和估计耳蜗非线性。然而，耳声发射如何离开耳蜗的基本问题仍然没有答案。在这项研究中，发射是由具有恒定频率比的两个音调引起的，并以基底膜和镫骨处的振动以及耳道中的声压来测量。通过测量基底膜和镫骨振动之间的相位差来确定发射的传播方向和延迟。这些测量结果表明，耳蜗产生的声音到达镫骨早于测量的基底膜位置。数据还表明，在发射频率的基底膜振动是类似的外部音调引起的。这些结果与后向行波理论相冲突，并表明在低和中等声级下，发射主要通过耳蜗液离开耳蜗。
The auditory sensory organ, the cochlea, not only detects but also generates sounds. Such sounds, otoacoustic emissions, are widely used for diagnosis of hearing disorders and to estimate cochlear nonlinearity. However, the fundamental question of how the otoacoustic emission exits the cochlea remains unanswered. In this study, emissions were provoked by two tones with a constant frequency ratio, and measured as vibrations at the basilar membrane and at the stapes, and as sound pressure in the ear canal. The propagation direction and delay of the emission were determined by measuring the phase difference between basilar membrane and stapes vibrations. These measurements show that cochlea-generated sound arrives at the stapes earlier than at the measured basilar membrane location. Data also show that basilar membrane vibration at the emission frequency is similar to that evoked by external tones. These results conflict with the backward-traveling-wave theory and suggest that at low and intermediate sound levels, the emission exits the cochlea predominantly through the cochlear fluids.