BIOLOGICAL CONSTRAINTS ON TUNING IN THE INNER EAR

描述：（改编自申请人的摘要。）的总目标 拟议的研究是对解剖学和 脊椎动物听觉系统中频率选择性的神经基础。 具体而言，拟议研究的主要目标有两个： 提供深入了解刺激相互作用的机制， 影响脊椎动物听觉系统的调谐， 理解和欣赏频率的细胞基础 分辨率 为了实现第一个目标，研究人员 将（1）阐明双音抑制之间的潜在关系 通过检查和比较他们的听觉神经， 温度依赖性，（2）量化对侧声音对 单个听觉神经纤维的调谐特性，以及（3） 系统地研究了低水平振动刺激对 个别低频听觉神经元的听觉调谐特性。 为了实现第二个目标，申请人将（1）准确地 表征听毛细胞的膜电流，以确定其 温度依赖性，从而评估它们对调谐的贡献， 以及（2）与解剖学精细结构（细胞体尺寸、轴突 尺寸，神经支配模式），以调整所识别的 听觉神经纤维 这些数据来自于这种结构-功能 方法将丰富的解剖和神经方面的影响， 处理复杂声音的基底，而这项工作 将成为理解人类基本问题的典范 语音和音乐感知在不利的（嘈杂的）环境。

DESCRIPTION: (Adapted from the Applicant's Abstract.) The overall goal of the proposed research is a deeper understanding of the anatomical and neural bases of frequency selectivity in the vertebrate auditory system. In particular, the primary objectives of the proposed research are two: to provide insights into the mechanisms underlying stimulus interactions which affect tuning in the vertebrate auditory system, and to gain an understanding and appreciation of the cellular bases of frequency resolution. To accomplish the first of these objectives the investigators will (1) elucidate the underlying relationship between two-tone suppression and tuning in the auditory nerve by examining and comparing their temperature dependencies, (2) quantify the effect of contralateral sound on the tuning properties of single auditory nerve fibers, and (3) systematically study the effect of low-level vibratory stimulation on the auditory tuning properties of individual low-frequency auditory neurons. To carry out the second objective, the applicants will (1) precisely characterize membrane currents of auditory hair cells to determine their temperature dependencies, and thus to assess their contribution to tuning, and (2) relate anatomical fine structure (cell body dimensions, axon dimensions, innervation pattern) to tuning properties of identified auditory nerve fibers. Such data that result from this structure-function approach will be rich in implications regarding the anatomical and neural substrate underlying the processing of complex sounds, and that this work will serve as a model for understanding fundamental problems of human speech and music perception in adverse (noisy) environments.