Perception of across-frequency asynchrony and the role of cochlear delays.
Perception of across-frequency asynchrony and the role of cochlear delays.
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DOI：
10.1121/1.3665995
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发表时间：
2012-01
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影响因子：
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通讯作者：
M. Wojtczak;Jordan A. Beim;C. Micheyl;A. Oxenham
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文献类型：
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作者：
M. Wojtczak;Jordan A. Beim;C. Micheyl;A. Oxenham
耳蜗过滤导致对高频的反应比对低频的反应更早。这项研究通过测量不同频率音调之间相对时间的感知来检查耳蜗延迟的潜在感知相关性。简短的 250 Hz 音调与简短的 1、2、4 或 6 kHz 音调相结合。进行了两项实验，一项涉及感知同步的主观判断，另一项涉及异步检测和辨别。对于所有音调对来说，将“同步”响应的比例与音调之间的延迟相关的函数是类似的。当一对音调被同步选通时，感知的同步性达到最大。感知同步函数斜率是不对称的，低频领先侧更陡。在第二个实验中，低频前导对的异步检测阈值低于高频前导对的异步检测阈值。与之前的研究相反，但与第一个实验一致，阈值并不依赖于音调之间的频率间隔，这可能是因为消除了通道内线索。使用决策理论模型将两个实验的结果定量相关，并且发现高度相关。总体而言，结果表明频率相关的耳蜗群延迟在较高的处理阶段得到补偿，从而导致跨频率的时序关系的真实感知。
Cochlear filtering results in earlier responses to high than to low frequencies. This study examined potential perceptual correlates of cochlear delays by measuring the perception of relative timing between tones of different frequencies. A brief 250-Hz tone was combined with a brief 1-, 2-, 4-, or 6-kHz tone. Two experiments were performed, one involving subjective judgments of perceived synchrony, the other involving asynchrony detection and discrimination. The functions relating the proportion of "synchronous" responses to the delay between the tones were similar for all tone pairs. Perceived synchrony was maximal when the tones in a pair were gated synchronously. The perceived-synchrony function slopes were asymmetric, being steeper on the low-frequency-leading side. In the second experiment, asynchrony-detection thresholds were lower for low-frequency rather than for high-frequency leading pairs. In contrast with previous studies, but consistent with the first experiment, thresholds did not depend on frequency separation between the tones, perhaps because of the elimination of within-channel cues. The results of the two experiments were related quantitatively using a decision-theoretic model, and were found to be highly correlated. Overall the results suggest that frequency-dependent cochlear group delays are compensated for at higher processing stages, resulting in veridical perception of timing relationships across frequency.