Department of Biology and Environmental Sciences, Animal Physiology and Behavior Group, Carl-von-Ossietzky University Oldenburg, Postfach 2503, 26111 Oldenburg, Germany.
J Acoust Soc Am. 2010 Jul;128(1):280-90. doi: 10.1121/1.3436552.
By applying a Go/NoGo paradigm, thresholds for detecting mistuning of components of a 200 Hz complex were determined in the Mongolian gerbil and compared with thresholds obtained in a previous study with an 800 Hz complex. Frequency difference limens (FDLs) for detecting mistuning decreased with increasing harmonic frequency and harmonic number (0.5% to 0.01% Weber fraction). It was furthermore examined how starting and ending the mistuned component earlier than the remaining complex affects the FDL (duration of all components 400 ms, time shift 30 to 500 ms). Large FDLs that are similar to pure tone FDLs (between 21% and 6.7%) were found for onset asynchronies of 300 ms and more, indicating separate processing of the mistuned component. Small FDLs that are similar to FDLs of the synchronous condition were found if the temporal overlap between the mistuned component and the remaining complex was 100 ms or more. These experimental data in combination with a simulation of processing of the harmonic complexes by the gerbil's peripheral auditory filters led to the conclusion that the phase and amplitude modulations in the filter outputs can provide cues that allow gerbils a sensitive detection of mistuning across a wide range of frequencies.
通过应用 Go/NoGo 范式，确定了蒙古沙鼠检测 200 Hz 复音成分失谐的阈值，并与之前使用 800 Hz 复音进行的研究中获得的阈值进行了比较。检测失谐的频率差极限 (FDL) 随着谐波频率和谐波数的增加而降低（0.5%至 0.01%韦伯分数）。此外，还研究了在剩余复音之前更早地开始和结束失谐成分如何影响 FDL（所有成分持续时间为 400 毫秒，时间偏移为 30 至 500 毫秒）。对于 300 毫秒及以上的起始异步，发现 FDL 较大，类似于纯音 FDL（21%至 6.7%之间），表明失谐成分的单独处理。如果失谐成分与剩余复音之间的时间重叠为 100 毫秒或更长，则会发现 FDL 较小，类似于同步条件下的 FDL。这些实验数据结合对沙鼠外周听觉滤波器处理谐波复音的模拟，得出结论，滤波器输出中的相位和幅度调制可以提供线索，使沙鼠能够在广泛的频率范围内对失谐进行敏感检测。
