Dancer A
Institut Franco-Allemand de Recherches de Saint-Louis, Cedex.
C R Seances Soc Biol Fil. 1993;187(5):650-65.
The effects of noise on the auditory transduction and the temporary and permanent threshold shifts (TTS and PTS) are reviewed in relation to the physiology, the morphology and the mechanics of the Corti's organ and especially of the outer hair cells. The modification of the mechanical characteristics of the stereocilia: decrease of stiffness, shortening of the rootlets, softening of the interciliary links...reduce the number of ionic channels which are opened during the mechanical excitation of the Corti's organ. This reduction modifies greatly the behavior of the "cochlear amplifier" which is located at the level of the outer hair cells and is responsible for the auditory sensitivity at threshold and the frequency selectivity. Permanent damages to the stereocilia of the hair cells following exposure to noise seem to be the main factor responsible for the apparition and the extent of the hearing losses. The influence cof several parameters: amplitude, duration, frequency..., on TTS and PTS are reviewed and the phenomenon of the half-octave shift is described.
本文综述了噪声对听觉转导以及暂时性和永久性阈移（TTS和PTS）的影响，并与柯蒂氏器尤其是外毛细胞的生理学、形态学和力学相关。静纤毛机械特性的改变：刚度降低、小根缩短、纤毛间连接软化……减少了柯蒂氏器机械兴奋过程中打开的离子通道数量。这种减少极大地改变了位于外毛细胞水平的“耳蜗放大器”的行为，该放大器负责阈值处的听觉敏感性和频率选择性。暴露于噪声后毛细胞静纤毛的永久性损伤似乎是听力损失出现及其程度的主要因素。本文还综述了几个参数：幅度、持续时间、频率……对TTS和PTS的影响，并描述了半倍频程移位现象。
