Auditory brainstem correlates of basilar membrane nonlinearity in humans.
Auditory brainstem correlates of basilar membrane nonlinearity in humans.
复制标题
听觉脑干与人类基底膜非线性相关。
DOI：
10.1159/000158537
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发表时间：
2009
影响因子：
1.6
通讯作者：
Krishnan A
中科院分区：
文献类型：
--
作者：
Krishnan A
基底膜响应的行为测量可以通过比较掩模在信号频率和远低于信号频率处的正向掩蔽的增长来获得。由于假定低频掩蔽器在信号处被线性处理，因此掩蔽器随电平增长的差异被认为反映了对频掩器的压缩响应。目前的实验使用了这种技术的电生理模拟，基于对听觉脑干反应的V波潜伏期的测量，该反应是由4khz， 4ms的纯音在65 dB SPL下引起的。响应是在安静的情况下获得的，并且存在频率正常（4 kHz）或频率异常（1.8 kHz）的纯音前向掩蔽器。波V延迟随着掩蔽器水平的增加而增加，尽管低频掩蔽器的增加幅度大于高频掩蔽器，这与后者的压缩响应一致。由数据生成的响应函数呈现出特征形状，在较低级别近似线性响应，在较高级别为4:1压缩。然而，线性区和压缩区之间的断点约为60 dB SPL，高于先前生理和心理物理测量的预期。
A behavioral measure of the basilar membrane response can be obtained by comparing the growth in forward masking for maskers at, and well below, the signal frequency. Since the off-frequency masker is assumed to be processed linearly at the signal place, the difference in masking growth with level is thought to reflect the compressive response to the on-frequency masker. The present experiment used an electrophysiological analog of this technique, based on measurements of the latency of wave V of the auditory brainstem response elicited by a 4-kHz, 4-ms pure tone, presented at 65 dB SPL. Responses were obtained in quiet and in the presence of either an on-frequency (4 kHz) or an off-frequency (1.8 kHz) pure-tone forward masker. Wave V latency increased with masker level, although the increase was greater for the off-frequency masker than for the on-frequency masker, consistent with a more compressive response to the latter. Response functions generated from the data showed the characteristic shape, with a nearly linear response at lower levels and 4:1 compression at higher levels. However, the breakpoint between the linear region and the compressive region was at about 60 dB SPL, higher than expected on the basis of previous physiological and psychophysical measures.