Cochlear Mechanics

描述（由申请人提供）：耳蜗力学测量是理解许多临床和心理物理现象的关键。当没有足够的数据来限制解释时，有许多方法可以“解释”耳蜗力学，这些方法与实际的听力物理几乎没有关系。这些研究的中心目标是为解释从耳蜗神经的生理研究或心理物理学研究中获得的观察结果提供数据库，这些研究的数据随后由听觉外围产生的转换。大多数耳蜗力学测量都是在耳蜗的基底区进行的，而耳蜗的顶端区域是大多数人类交流声音被处理的地方。测量将在根尖和中频区域进行，以提供在这个关键区域使用位移测量激光干涉仪的力学直接观察。这些测量应确定是否存在耳蜗放大，并从耳蜗基部到耳蜗顶端连续下降。耳蜗力学中压缩非线性的一个结果是对复杂信号的响应不能基于纯音响应来预测。拟议的研究旨在确定多音和语音样（双峰）信号复合物在耳蜗基部、中部和顶端区域的表征。基底膜在这些区域的瞬态响应将由压晶驱动器提供的理想脉冲直接驱动镫骨来确定，以避免中耳的贡献。畸变产物耳声发射和机械振动将在正常动物和听神经病变动物模型中同时测量。耳蜗的交叉传出调制将被研究使用声学刺激对侧耳在一个失忆的对象。机械测量将与同一物种使用相同信号的听神经反应进行比较。

DESCRIPTION (provided by applicant): Cochlear mechanical measurements are crucial to understanding many of clinical and psychophysical phenomena. There are many ways to 'explain' cochlear mechanics that have little to do with actual I physics of hearing when there is insufficient data to constrain interpretations. A central goal of these studies is to provide the database for interpreting observations obtained from physiological studies of the cochlear nerve or from psychophysical studies from which data are subsequent to transformations engendered by the auditory periphery. Most cochlear mechanical measurements have been made in the basal region of the cochlea while the apical region is where most human communication sounds are processed. Measurements will be made in both the apical and mid-frequency regions to provide direct observations of mechanics in this critical region using a displacement measuring laser interferometer. These measurements should settle whether cochlear amplification exists and decreases continuously From base to apex. An outcome the compressive nonlinearity in cochlear mechanics is that the response to complex signals cannot be predicted based on pure-tone responses. Proposed studies are designed to determine the representation of multi-tone and speech-like (two-formant) signal complexes in the base, middle and apical region of the cochlea. The transient response of the basilar membrane in these regions will be determined by directly driving the stapes with an ideal impulse delivered from a piezocrystal driver to avoid the contribution of the middle ear. Distortion product otoacoustic emissions and mechanical vibrations will be measured simultaneously in both normal animals and an animal model of auditory neuropathy. Crossed efferent modulation of the cochlea will be studied using acoustic stimulation of the contralateral ear in a decerebrate subject. Mechanical measurements will be compared I to auditory nerve responses in the same species and using the same signals.