RUI: Investigating the Effect of Hair Bundle Hydrodynamics in the Inner Ear

本研究的一个重要目标是了解内耳毛束结构的形态与功能之间的关系；特别是，大小和形状如何影响他们对不同频率刺激的反应。另一个目标是了解上覆膜在毛细胞敏感性中的作用。听力器官的毛束通常由一层被称为被盖膜的覆盖膜覆盖。比较一个代表上覆膜的模型和一个不代表上覆膜的模型的流体动力学应该阐明上覆膜在毛细胞敏感性中的作用。首席研究员之前研究了单个头发束作为二维皮瓣和三维半球的流体动力学。三维分析表明，二维模型不能很好地反映低频时的毛束动力学。这个新的研究项目旨在从两个方向扩展半球模型：包括中频，以及分析在低频和高频区域有覆盖膜的模型。学生将以几种方式参与这项研究：通过比较不同解法的结果求得基本解的分布；通过使毛发束和周围液体的运动产生动画效果；通过对奇点法的研究；研究神经调谐曲线的特征。本研究将增进学生对流体流动、数值分析、耳生理学及电脑程式设计等领域的了解。研究结果有望为听觉科学的知识库和流体的数值模拟做出贡献。在微力学领域，这些新知识可能有助于开发声音和运动的微机械传感器。

Shatz0099753An important goal of this research is to understand the relationship between the morphology of inner ear hair bundle structures and their functionality; in particular, how the size and shape affects their response to stimuli of different frequencies. Another goal is to understand the role that an overlying membrane has in hair cell sensitivity. Hair bundles of hearing organs are usually topped by an overlying membrane called the tectorial membrane. Comparing the hydrodynamics of a model which represents an overlying membrane to one that does not should elucidate the role of an overlying membrane in hair cell sensitivity. The principal investigator previously investigated the hydrodynamics of a single hair bundle as a two-dimensional flap and as a three-dimensional hemispheroid. The 3-D analysis indicated that the 2-D model does not adequately represent hair bundle dynamics at low frequencies. This new research project is designed to extend the hemispheroid model in two directions: to include mid-frequencies, and to analyze a model with an overlying membrane in the low and high frequency regions. Students are to participate in this research in several ways: by comparing the results of different methods of solving for the distribution of the fundamental solutions; by animating the motion of the hair bundles and surrounding fluid; by studying the singularity method; studying the features of neural tuning curves. The research will enhance the students' understanding in the areas of fluid flows, numerical analysis, ear physiology, and computer programming. Results from the research are expected to contribute to the knowledge base of auditory science and also to numerical modeling of fluids. In the field of micro-mechanics the new knowledge may prove useful in developing micro-mechanical transducers of sound and motion.