Waisman Center, University of Wisconsin, 1500 Highland Avenue, Madison, Wisconsin 53705, USA.
J Acoust Soc Am. 2012 Sep;132(3):1561-72. doi: 10.1121/1.4740498.
The role of envelope statistics in binaural masking-level differences (BMLDs) and correlation change detection was investigated in normal-hearing listeners. Thresholds and just-noticeable differences (JNDs) were measured for different bandwidths and center frequencies (500, 2000, 4000, and 8000 Hz) using Gaussian noises (GNs) and low-fluctuation noises (LFNs). At a 500-Hz center frequency, GN NoSo thresholds were higher than, NoSπ thresholds were lower than, and correlation change detection JNDs were the same as LFN thresholds and JNDs. At higher center frequencies, GN NoSπ thresholds were the same or higher than LFN thresholds and GN correlation change detection JNDs were much smaller than LFN JNDs. Using a pulsed sine vocoder, a second experiment was performed to investigate if binaural adaptation might contribute to the difference in GN and LFN detection. There was no effect of pulse rate, thus providing no clear evidence that binaural adaptation plays a role in these tasks. Both a cross-correlation model and a model that utilized the fluctuations in the interaural differences could explain a majority of the variance in the LFN correlation change JNDs.
研究了包络统计数据在正常听力受试者的双耳掩蔽级差（BMLDs）和相关变化检测中的作用。使用高斯噪声（GN）和低波动噪声（LFN）测量了不同带宽和中心频率（500、2000、4000 和 8000 Hz）的阈值和可察觉差异（JND）。在 500 Hz 的中心频率下，GN NoSo 阈值高于 NoSπ阈值，而相关变化检测 JND 与 LFN 阈值和 JND 相同。在更高的中心频率下，GN NoSπ阈值与 LFN 阈值相同或更高，而 GN 相关变化检测 JND 远小于 LFN JND。使用脉冲正弦声码器进行了第二个实验，以研究双耳适应是否可能导致 GN 和 LFN 检测的差异。脉冲率没有影响，因此没有明确证据表明双耳适应在这些任务中起作用。交叉相关模型和利用双耳差异波动的模型都可以解释 LFN 相关变化 JND 中大部分的方差。
