Department of Medical Physics and Acoustics, University of Oldenburg, Oldenburg, Germany.
Cluster of Excellence 'Hearing4all', University of Oldenburg, Oldenburg, Germany.
Commun Biol. 2022 Oct 22;5(1):1122. doi: 10.1038/s42003-022-04098-x.
Sound in noise is better detected or understood if target and masking sources originate from different locations. Mammalian physiology suggests that the neurocomputational process that underlies this binaural unmasking is based on two hemispheric channels that encode interaural differences in their relative neuronal activity. Here, we introduce a mathematical formulation of the two-channel model - the complex-valued correlation coefficient. We show that this formulation quantifies the amount of temporal fluctuations in interaural differences, which we suggest underlie binaural unmasking. We applied this model to an extensive library of psychoacoustic experiments, accounting for 98% of the variance across eight studies. Combining physiological plausibility with its success in explaining behavioral data, the proposed mechanism is a significant step towards a unified understanding of binaural unmasking and the encoding of interaural differences in general.
如果目标和掩蔽源来自不同的位置，那么在噪声中的声音会更容易被检测到或理解。哺乳动物生理学表明，这种双耳掩蔽的神经计算过程基于两个半球通道，它们以相对神经元活动的耳间差异进行编码。在这里，我们引入了双通道模型的数学公式 - 复相关系数。我们表明，这种公式量化了耳间差异的时间波动量，我们认为这是双耳掩蔽的基础。我们将这个模型应用于一个广泛的心理声学实验库，解释了八项研究中 98%的方差。结合生理合理性及其对行为数据的解释能力，所提出的机制是朝着对双耳掩蔽和一般的耳间差异编码的统一理解迈出的重要一步。
