Sinnott J M, Brown C H
Psychology Department, University of South Alabama, Mobile 36688.
J Acoust Soc Am. 1993 Mar;93(3):1535-40. doi: 10.1121/1.406811.
This study examined the effects of presenting various signal and noise levels on pure-tone frequency difference limens (FDLs) in humans and monkey. Signal levels for two frequencies of 500 Hz and 4 kHz were varied both in quiet and in noise. For the lower frequency of 500 Hz, the two species exhibited qualitatively divergent FDLs as level increased in quiet: FDLs decreased at high levels for humans, but increased for monkeys. In noise, differences between human and monkey FDLs were less pronounced. At 500 Hz, monkeys exhibited slightly lower FDLs in noise than in quiet. At the higher frequency of 4 kHz, under all conditions, FDLs for both species were qualitatively similar. Results are discussed in relation to (1) different use of "temporal" coding mechanisms by humans and monkeys at 500 Hz, and (2) similar use of "rate-place" coding mechanisms at 4 kHz.
本研究考察了呈现不同信号和噪声水平对人类和猴子纯音频率辨别阈限（FDLs）的影响。500赫兹和4千赫这两个频率的信号水平在安静环境和噪声环境中均有所变化。对于500赫兹这个较低频率，随着安静环境中信号水平的增加，这两个物种呈现出质的不同的FDLs：人类在高信号水平时FDLs降低，而猴子的FDLs增加。在噪声环境中，人类和猴子FDLs之间的差异不太明显。在500赫兹时，猴子在噪声环境中的FDLs略低于安静环境中的。在4千赫这个较高频率下，在所有条件下，两个物种的FDLs在质上是相似的。结果根据以下两点进行了讨论：（1）人类和猴子在500赫兹时对“时间”编码机制的不同运用，以及（2）在4千赫时对“速率-位置”编码机制的相似运用。
