Department of Speech and Hearing Sciences, University of Washington, 1417 NE 42nd Street, Seattle, Washington 98105, USA.
J Acoust Soc Am. 2013 Aug;134(2):1242-52. doi: 10.1121/1.4812857.
Temporal variation in listeners' sensitivity to interaural time and level differences (ITD and ILD) was assessed using the temporal weighting function (TWF) paradigm [Stecker and Hafter (2002). J. Acoust. Soc. Am. 112, 1046-1057] in the context of sound-source lateralization. Brief Gabor click trains were presented over headphones with overall ITD and/or ILD ranging ±500 μs ITD and/or ±5 dB ILD across trials; values for individual clicks within each train varied by an additional ±100 μs or ±2 dB to allow TWF calculation by multiple regression. In separate conditions, TWFs were measured for (i) ITD alone, (ii) ILD alone, (iii) ITD and ILD covarying ("in agreement"), and (iv) ITD and ILD varying independently across clicks. Consistent with past studies that measured TWF for binaural discrimination, TWFs demonstrated high weight on the first click for stimuli with short interclick interval (ICI = 2 ms), but flatter weighting for longer ICI (5-10 ms). Some conditions additionally demonstrated greater weight for clicks near the offset than near the middle of the train [Stecker and Hafter (2009). J. Acoust. Soc. Am. 125, 3914-3924]. The latter result was observed only when stimuli carried ILD, and appeared more reliably for 5 ms than for 2 or 10 ms ICI.
使用声源定位中的时频加权函数 (TWF) 范式[Stecker 和 Hafter (2002)。J. Acoust. Soc. Am. 112, 1046-1057]评估了听众对耳间时间和水平差异 (ITD 和 ILD) 的敏感性的时间变化。在整个试验中，使用耳机呈现总体 ITD 和/或 ILD 范围为 ±500 μs ITD 和/或 ±5 dB ILD 的短 Gabor 点击音序列；在每个音序列中，每个点击的单独值会额外变化 ±100 μs 或 ±2 dB，以允许通过多元回归计算 TWF。在单独的条件下，测量了 TWF 用于 (i) ITD 单独，(ii) ILD 单独，(iii) ITD 和 ILD 共同变化（“一致”），以及 (iv) ITD 和 ILD 在各次点击之间独立变化。与过去测量双耳辨别 TWF 的研究一致，TWF 对具有短音间间隔 (ICI=2 ms) 的刺激的第一个点击具有较高的权重，但对于较长的 ICI（5-10 ms）的权重则较平坦。一些条件还显示了在音序列的结束附近比中间附近的点击的权重更大[Stecker 和 Hafter (2009)。J. Acoust. Soc. Am. 125, 3914-3924]。仅当刺激带有 ILD 时才观察到后一种结果，并且在 ICI 为 5 ms 时比 2 或 10 ms 时更可靠地观察到该结果。
