Observing auditory mechanics with pressure and motion measurements

描述（由申请人提供）：本研究的主要目的是进一步了解健康耳蜗的力学。第二个目的是了解声音如何通过健康的中耳传播。为了实现这些目标，我们使用两个强大的实验技术：颅内压力测量和干涉测量颅内和中耳运动。具体实验测量耳蜗内的声音传输以探索耳蜗的主动力学和耳蜗行波之间的相互作用，以及耳蜗和耳道之间的声音传输以确定中耳如何过滤耳蜗发射。其他实验将测量耳蜗基底膜的详细运动;微妙的空间变化可以揭示基于细胞的力量的运作，这些力量塑造了耳蜗调谐。为了了解耳蜗调谐的被动基底，有趣的“主动”细胞为基础的力量必须建立在此基础上，一个实验将测量耳蜗基底膜和Corti器官的刚度和阻力，另一个实验将测量耳蜗的调谐，其中Corti器官被耳毒性损伤。最后，一个实验将追踪观察到的中耳传输延迟的来源。这些测量旨在了解正常耳蜗和中耳的力学。然而，它们对听力受损者的治疗具有重要意义。虽然人工耳蜗植入取得了惊人的成功，但植入物的功能性听力与音乐，语言和自然的自然听觉体验之间仍然存在分歧。为了缩小这一鸿沟，人工耳蜗和助听器将继续得到改进，更好地了解耳蜗的自然处理过程将有利于这项工作。除了植入物和艾滋病，通过再生或修复耳蜗毛细胞的疗法修复Corti器官的前景是非常令人兴奋的，对正常机制的理解将有助于指导这些进展。在中耳的情况下，手术治疗是可行的，但并不总是成功的。更好地了解声音通过中耳的传播是这项提议的目标之一，获得这些知识可能会影响其手术修复。

DESCRIPTION (provided by applicant): The primary objective of this research is to further our understanding of the mechanics of the healthy cochlea. A secondary objective is to understand how sound is transmitted through the healthy middle ear. To attain these objectives we use two powerful experimental techniques: intracochlear pressure measurements and interferometric measurements of intracochlear and middle ear motion. Specific experiments measure sound transmission within the cochlea to explore the interaction between the cochlea's active mechanics and the cochlear traveling wave, and sound transmission between the cochlea and the ear canal to determine how the middle ear filters cochlear emissions. Other experiments will measure detailed motion of the cochlea's basilar membrane; subtle spatial variations could reveal the operation of the cell based forces that shape cochlear tuning. In order to understand the passive substrate for cochlear tuning, upon which the interesting "active" cell-based forces must build, one experiment will measure the stiffness and resistance of the cochlea's basilar membrane and organ of Corti in situ, another will measure tuning in cochleae in which the organ of Corti was ototoxically damaged. Finally, one experiment will trace the source of the observed middle ear transmission delay. The measurements are aimed at understanding the mechanics of the normal cochlea and middle ear. Nevertheless, they are significant to the treatment of the hearing impaired. While cochlear implants have been breathtakingly successful, a divide remains between the functional hearing available with an implant and the natural auditory experience of music, language, and nature. To decrease this divide, cochlear implants and hearing aids continue to be improved and a better understanding of the natural processing of the cochlea will benefit this work. Beyond implants and aids, the promise of repairing the organ of Corti through therapies that regenerate or repair cochlear hair cells is very exciting, and the understanding of the normal mechanics will help guide these advances. In the case of the middle ear, surgical therapies are available but are not always successful. Better understanding the transmission of sound through the middle ear is one of the goals of this proposal, and gaining that knowledge could influence its surgical repair.