Narayan S S, Temchin A N, Recio A, Ruggero M A
The Hugh Knowles Center, Audiology and Hearing Sciences Program, Department of Communication Sciences and Disorders, and Institute for Neuroscience, Northwestern University, Evanston, IL 60208-3550, USA.
Science. 1998 Dec 4;282(5395):1882-4. doi: 10.1126/science.282.5395.1882.
Responses to tones of a basilar membrane site and of auditory nerve fibers innervating neighboring inner hair cells were recorded in the same cochleae in chinchillas. At near-threshold stimulus levels, the frequency tuning of auditory nerve fibers closely paralleled that of basilar membrane displacement modified by high-pass filtering, indicating that only relatively minor signal transformations intervene between mechanical vibration and auditory nerve excitation. This finding establishes that cochlear frequency selectivity in chinchillas (and probably in mammals in general) is fully expressed in the vibrations of the basilar membrane and renders unnecessary additional ("second") filters, such as those present in the hair cells of the cochleae of reptiles.
在龙猫的同一耳蜗中，记录了基底膜某一部位以及支配相邻内毛细胞的听神经纤维对音调的反应。在接近阈值的刺激水平下，听神经纤维的频率调谐与经过高通滤波修改后的基底膜位移频率调谐密切平行，这表明在机械振动和听神经兴奋之间仅存在相对较小的信号转换。这一发现表明，龙猫（可能一般哺乳动物也是如此）的耳蜗频率选择性在基底膜的振动中得到了充分体现，使得诸如爬行动物耳蜗毛细胞中存在的额外（“二级”）滤波器变得不再必要。
