Hall J L
J Acoust Soc Am. 1978 Aug;64(2):473-7. doi: 10.1121/1.382019.
Zwicker has demonstrated that the threshold for a high-frequency test-tone burst in the presence of a continuous low-frequency masking tone is a complicated function of the frequency and intensity of the masker and the phase of the masker at which the test tone is presented. "Masking period patterns" measured for these stimuli show nonlinear effects in that a high masker levels the threshold of test-tone bursts reaches local maxima at two different phases of the masker. We have investigated the implications of these psychophysical data on a computational model for motion of the basilar membrane. The model consists of a nonlinear mechanical system followed by an additional stage of frequency selectivity ("second filter"). The output of the model is applied as input to a threshold-level detector. With this model it is possible to reproduce the effects Zwicker observed. Masking period patterns are interpreted as a manifestation of two-tone suppression. On the basis of our computer simulation of Zwicker's psychophysical data, we make the following specific predictions concerning the nature of mechanical to neural transduction at the auditory periphery: (1) Membrane motion in one direction produces a nonlinear increase in the loss term, while membrane motion in the other direction does not. (2) The direction of membrane motion that produces increased loss is also the direction of motion that produces neural excitation. (3) There is a stage of sharpening, a "second filter," between membrane motion and the neural excitatory signal.
茨维克已经证明，在持续的低频掩蔽音存在的情况下，高频测试音脉冲的阈值是掩蔽音的频率、强度以及呈现测试音时掩蔽音相位的复杂函数。针对这些刺激测量的“掩蔽周期模式”显示出非线性效应，即高掩蔽音水平下测试音脉冲的阈值在掩蔽音的两个不同相位处达到局部最大值。我们已经研究了这些心理物理学数据对基底膜运动计算模型的影响。该模型由一个非线性机械系统和一个额外的频率选择阶段（“第二滤波器”）组成。模型的输出被用作阈值水平检测器的输入。利用这个模型，可以重现茨维克观察到的效应。掩蔽周期模式被解释为双音抑制的一种表现。基于我们对茨维克心理物理学数据的计算机模拟，我们对听觉外周机械到神经转导的性质做出以下具体预测：（1）一个方向的膜运动在损失项中产生非线性增加，而另一个方向的膜运动则不会。（2）产生损失增加的膜运动方向也是产生神经兴奋的运动方向。（3）在膜运动和神经兴奋信号之间存在一个锐化阶段，即“第二滤波器”。
