Modeling and Analysis of Wave Amplification in the Cochlea

耳蜗波放大的建模与分析

• 批准号: 1122279
• 负责人: Mark Holmes
• 金额: $ 32.34万
• 依托单位: Rensselaer Polytechnic Institute
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-10-01 至 2016-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1122279&HistoricalAwards=false
• 关键词: Modeling; Analysis; Wave; Amplification; Cochlea

During the funding period a systematic reduction of the equations of motion for the cochlear amplifier will be carried out. The objective is to derive an effective surface approximation for the partition, after which multiple-scales will be used to derive an asymptotic approximation of the nonlinear waves propagating in the cochlea. The objective is to be able to achieve quantitative agreement with the known properties of these waves, including the apical shift in the tuning curve at low intensity levels, the decrease of the relative contribution of the amplifier with increasing stimulus level, the odd-order distortion tones, the observation that the temporal position of the zero-crossings on the basilar membrane remain largely unaffected by stimulus intensity, and the dearth of harmonic distortion in the basilar membrane response to pure tones at low to moderate sound pressure levels in the basal portion of the cochlea.The fundamental open question in understanding how we hear concerns the role of a nonlinear feedback mechanism known as the cochlear amplifier. One of the reasons why progress in delineating the exact mechanism responsible for amplification is so slow is that it requires the solution of a three-dimensional, coupled, nonlinear, time-dependent system. The PI proposes to develop approximation methods that can be used to help study this problem, both the mechanistic basis for amplification as well as its effects on wave propagation in the cochlea. The results from this study will provide a rigorous framework to help answer the amplifier question.

在资助期间，将系统地简化人工耳蜗放大器的运动方程。 目标是导出分区的有效表面近似，然后使用多尺度导出耳蜗中传播的非线性波的渐近近似。 目标是能够与这些波的已知特性达成定量一致，包括低强度水平下调谐曲线的顶端移动、放大器的相对贡献随着刺激水平的增加而减少、奇数阶失真音调、基底膜上过零的时间位置在很大程度上不受刺激强度影响的观察结果以及谐波失真的缺乏。 耳蜗基底部分中低至中等声压级的基底膜对纯音的反应。理解我们如何听到声音的基本开放问题涉及称为耳蜗放大器的非线性反馈机制的作用。 描述放大的确切机制进展如此缓慢的原因之一是它需要三维、耦合、非线性、瞬态系统的解。 PI 建议开发近似方法来帮助研究这个问题，包括放大的机械基础及其对耳蜗中波传播的影响。 这项研究的结果将提供一个严格的框架来帮助回答放大器问题。