Cochlear Mechanics

描述(由申请人提供)：耳蜗力学测量对于理解许多临床和心理物理现象至关重要。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觉物理学几乎没有什么关系。这些研究的一个中心目标是提供数据库，用于解释从耳蜗神经生理研究或心理物理研究获得的观察结果，这些研究的数据是在听觉外周产生的转换之后获得的。大多数耳蜗力学测量是在耳蜗基底部进行的，而顶端区域是处理大多数人类交流声音的地方。将在尖端和中频区域进行测量，以便使用位移测量激光干涉仪直接观察这一关键区域的力学。这些测量应该确定是否存在耳蜗放大，并从底部到顶端持续减少。耳蜗力学中压缩非线性的一个结果是，不能基于纯音反应来预测对复杂信号的反应。拟议的研究旨在确定多音和类语音(两共振峰)信号复合体在耳蜗基底部、中部和顶端区域的表现。这些区域的基底膜的瞬变响应将通过用压电晶体驱动器发出的理想脉冲直接驱动月骨来确定，以避免中耳的贡献。在正常动物和听神经病动物模型中，将同时测量失真产物耳声发射和机械振动。在去大脑的受试者中，将使用对侧耳的声刺激来研究耳蜗区的交叉传出调制。机械测量将与同一物种的听神经反应进行比较，并使用相同的信号。

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.