Eggermont J J
Department of Psychology, University of Calgary, Alberta, Canada.
Hear Res. 1993 Feb;65(1-2):175-92. doi: 10.1016/0378-5955(93)90212-j.
Recordings were made from 185 neurons in the primary auditory cortex of cats in the age range of 15 to 297 days. A comparison was made between the tuning for click repetition-rate and for amplitude modulation-frequency of a noise burst on the basis of temporal Modulation Transfer Functions (tMTF). 90 of the 185 units had a clear band-pass type tMTF for both repetition rate and modulation frequency, there was, however, no correlation between the respective Best Modulation Frequencies (BMF). Amplitude modulated noise (AMnoise) was the more effective stimulus in young kittens while click-train stimulation was more effective in adult cats. For all neurons with significant synchronization, BMFs for both click-train and AMnoise increased with age from about 4 Hz in kittens younger than 30 days to about 10 Hz in adult cats. In the approximately 50% of the neurons that were tuned both to click rate and modulation frequency, however, the BMF to AMnoise was consistently and significantly higher than that for clicks. In this group the mean BMF for kittens younger than 30 days were 7.94 Hz for AMnoise and 3.29 Hz for clicks and in the adults 10.91 Hz for AMnoise and 7.71 Hz for clicks.
对年龄在15至297天的猫的初级听觉皮层中的185个神经元进行了记录。基于时间调制传递函数（tMTF），对噪声脉冲串的点击重复率调谐和幅度调制频率调谐进行了比较。185个单元中的90个对重复率和调制频率都有清晰的带通型tMTF，然而，各自的最佳调制频率（BMF）之间没有相关性。调幅噪声（AMnoise）对幼小猫是更有效的刺激，而点击序列刺激对成年猫更有效。对于所有具有显著同步性的神经元，点击序列和AMnoise的BMF随着年龄增长而增加，从小于30天的小猫中的约4Hz增加到成年猫中的约10Hz。然而，在大约50%既对点击速率又对调制频率进行调谐的神经元中，AMnoise的BMF始终显著高于点击的BMF。在这个组中，小于30天的小猫的AMnoise平均BMF为7.94Hz，点击为3.29Hz，成年猫中AMnoise为10.91Hz，点击为7.71Hz。
