Yost W A, Moore M J
J Acoust Soc Am. 1987 Jun;81(6):1896-905. doi: 10.1121/1.394754.
The spectral properties of a complex stimulus (rippled noise) were varied over time, and listeners were asked to discriminate between this stimulus and a flat-spectrum, stationary noise. The spacing between the spectral peaks of rippled noise was changed sinusoidally as a function of time, or the location of the spectral peaks of rippled noise was moved up and down the spectrum as a sinusoidal function of time. In most conditions, listeners were able to make the discriminations up to rates of temporal modulation of 5-10 cycles per second. Beyond 5-10 cps the rippled noise with the temporally varying peaks was indiscriminable from a flat (nonrippled) noise. The results suggest that for temporal changes in the spectral peaks of rippled noise, listeners cannot monitor the output of a single (or small number of) auditory channel(s) (critical bands), or that the mechanism used to extract the perceptual information from these stimuli is slow. Temporal variations in the spectral properties of rippled noise may relate to temporal changes in the repetition pitch of complex sounds, the temporal properties of the coloration added to sound in a reverberant environment, and the nature of spectral peak changes such as those that occur in speech-formant transitions. The results are relevant to the general issue of the auditory system's ability to extract information from a complex spectral profile.
复合刺激（波纹噪声）的频谱特性随时间变化，要求听众区分这种刺激与平坦频谱的固定噪声。波纹噪声频谱峰值之间的间距随时间呈正弦变化，或者波纹噪声频谱峰值的位置随时间呈正弦函数在频谱上上下移动。在大多数情况下，听众能够以每秒5至10个周期的时间调制率进行区分。超过5至10 cps，具有随时间变化峰值的波纹噪声与平坦（无波纹）噪声无法区分。结果表明，对于波纹噪声频谱峰值的时间变化，听众无法监测单个（或少数）听觉通道（临界频带）的输出，或者用于从这些刺激中提取感知信息的机制很慢。波纹噪声频谱特性的时间变化可能与复杂声音重复音高的时间变化、混响环境中声音添加的色彩的时间特性以及诸如语音共振峰转换中发生的频谱峰值变化的性质有关。这些结果与听觉系统从复杂频谱轮廓中提取信息的能力这一普遍问题相关。
