Puria S, Allen J B
AT&T Bell Laboratories, Murray Hill, New Jersey 07974.
J Acoust Soc Am. 1991 Jan;89(1):287-309. doi: 10.1121/1.400675.
In this paper various aspects of the cat cochlear input impedance Zc (omega) are implemented using a transmission line model having perilymph viscosity and a varying cross-sectional scalae area. These model results are then compared to the experimental results of Lynch et al. [J. Acoust. Soc. Am. 72, 108-130 (1982)]. From the model, the following observations are made about the cochlear input impedance: (a) Scalae area variations significantly alter the model Zc (omega); (b) the use of anatomically measured area improves the fits to the experimental data; (c) improved agreement between model and experimental phase is obtained when perilymph viscosity and tapering are included in the cochlear model for frequencies below approximately 150 Hz; (d) when model scalae tapering and perilymph viscosity are chosen to match physiological conditions, the effect of the helicotrema impedance on Zc (omega) is insignificant; and (e) the cochlear map, which is defined as the position of the basilar membrane peak displacement as a function of stimulus frequency, can have an important effect on Zc (omega) for frequencies below 500 Hz. A nonphysiological cochlear map can give rise to cochlear standing waves, which result in oscillations in Zc (omega). Scalae tapering and perilymph viscosity contribute significantly to the damping of these standing waves. These observations should dispel the previous notion that Zc (omega) is determined solely by parameters of the cochlea close to the stapes, and the notion that Zc (omega) is dominated by the helicotrema at low frequencies.
在本文中，使用具有外淋巴粘度和变化的蜗管横截面积的传输线模型，实现了猫耳蜗输入阻抗(Z_c(\omega))的各个方面。然后将这些模型结果与林奇等人的实验结果进行比较[《美国声学学会杂志》72, 108 - 130 (1982)]。从该模型中，对耳蜗输入阻抗有以下观察结果：(a) 蜗管面积变化会显著改变模型(Z_c(\omega))；(b) 使用解剖学测量的面积能更好地拟合实验数据；(c) 当在耳蜗模型中纳入外淋巴粘度和渐变时，对于低于约150 Hz的频率，模型与实验相位之间的一致性得到改善；(d) 当选择模型蜗管渐变和外淋巴粘度以匹配生理条件时，螺旋蜗孔阻抗对(Z_c(\omega))的影响微不足道；以及(e) 耳蜗图定义为基底膜峰值位移随刺激频率的位置，对于低于500 Hz的频率，它对(Z_c(\omega))可能有重要影响。非生理的耳蜗图会产生耳蜗驻波，这会导致(Z_c(\omega))出现振荡。蜗管渐变和外淋巴粘度对这些驻波的阻尼有显著贡献。这些观察结果应消除先前的观念，即(Z_c(\omega))仅由靠近镫骨的耳蜗参数决定，以及在低频时(Z_c(\omega))由螺旋蜗孔主导的观念。
