Exploring otoacoustic emissions with intracochlear pressure and motion measuremen

描述(由申请人提供)：本申请中提出的实验使用成熟的微压力传感器和激光多普勒振动计技术来探测与耳声发射(OAEs)相关的潜在耳蜗力学。这一应用旨在提供直接的在体耳内观察，以进一步了解反向传输中耳声发射的产生、传播和耳蜗信号处理的基本问题。第一个目标将探索反向传输中的耳蜗活动过程，其余的目标将继续和扩展我们之前关于失真产物OAEs(DPOAEs)在耳蜗组织中产生和传播的工作。OAEs是在耳蜗内产生的声音，在耳道中被检测到，携带着关于产生和塑造它们的机制的信息，从而提供了对耳蜗力学的非侵入性观察。然而，如何将耳声发射与耳蜗力学联系起来是耳声发射研究中的一大挑战。在正向方向，声音沿着耳蜗区产生行波，这是由外毛细胞的活动(耳蜗放大器)推动的。然而，耳蜗管放大器和耳蜗液在耳蜗逆传输中的作用尚不清楚。目的一是通过同步测量耳蜗腔内(基底膜速度和压力)和耳道压力，研究耳蜗声发射的发生部位，进一步探讨活动耳蜗声发射的多音抑制；目的二是量化前向和反向传输中的行波和压缩波压力；目的三是探讨耳蜗逆传输中的活动过程。因此，研究结果将为基础的耳蜗腔内观察提供基础，验证耳声发射的发生理论，并为建立三维耳蜗声发射模型奠定基础。最后，从目前的应用结果将导致更有效的耳声发射听力筛查方案用于研究和临床。

DESCRIPTION (provided by applicant): The experiments proposed in the current application use well-established micro-pressure-sensor and laser Doppler vibrometer techniques to probe underlying cochlear mechanics relating to otoacoustic emissions (OAEs). This application aims to provide direct intracochlear observation in vivo to further understand the fundamental questions in OAE generation, propagation and cochlear signal processing in reverse transmission. The first aim will explore the cochlear active process in reverse transmission and the rest of the aims will continue and extend our previous work on the generation and propagation of distortion product OAEs (DPOAEs) in the cochlea. OAEs are sounds generated within the cochlea and being detected in the ear canal, carrying the information about the mechanisms that generate and shape them, thus providing a noninvasive view into cochlear mechanics. However, how to relate OAE to cochlea mechanics is a big challenge in OAE research. In the forward direction, sound causes a traveling wave along the cochlear partition, which is boosted by the outer hair cells' activity (cochlear amplifier). However, the role of cochlear amplifier and cochlear fluid in cochlear reverse transmission is not clear. With simultaneous intracochlear (the basilar membrane velocity and intracochlear pressure) and ear canal pressure measurements, aim one studies the generation sites of OAE in the cochlea and further explore multiple tones suppression in active cochleae; aim two is designed to quantify the traveling wave and compression wave pressures in both forward and reverse transmissions; aim three explores the cochlear active process in reverse transmission. Thus the results will provide fundamental intracochlear observations, test the OAE generation theories and form the foundation for developing three-dimensional cochlear model. Finally, results from the current application will lead to more efficient OAE hearing screening program used in research and clinic.