Binaural interaction in low-frequency neurons in inferior colliculus of the cat. II. Effects of changing rate and direction of interaural phase.
Binaural interaction in low-frequency neurons in inferior colliculus of the cat. II. Effects of changing rate and direction of interaural phase.
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猫下丘低频神经元的双耳相互作用。
DOI：
10.1152/jn.1983.50.4.1000
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发表时间：
1983
影响因子：
2.5
通讯作者：
Kuwada,S
中科院分区：
文献类型：
--
作者：
Yin,TC;Kuwada,S
用双耳搏动刺激研究猫下丘(IC)神经元的耳间相位敏感性。双耳节拍是通过将频率稍有不同的音调传递给两只耳朵而产生的，它会在耳间产生连续和渐变的变化。超过90%的细胞对耳间延迟的变化表现出敏感性，也对双耳节拍的耳间相位差异表现出敏感性。细胞对节拍频率的每个完整周期都会产生脉冲响应。通过将后刺激时间直方图组合在拍频上而获得的周期直方图给出了细胞耳间相位灵敏度的测量。一般来说，由双耳节拍产生的周期直方图的形状与由耳间延迟得出的耳间相位曲线的形状以及由它们计算的平均耳间相角有很好的对应关系。拍频的大小决定了耳间相位的变化率，而符号决定了相位变化的方向。虽然大多数细胞以锁相方式响应，最高拍频为10赫兹，但也有一些细胞的锁相频率高达80赫兹。大多数细胞的拍频和平均耳间相角是线性相关的。大多数细胞在相变的两个方向上反应相同，但变化率不同，至少高达10赫兹。然而，一些IC细胞对相变的速度表现出显著的敏感性，要么在低拍频率下反应更强烈，要么在高拍频率下反应更强烈。此外，其他细胞表现出明显的方向性敏感性。对相位变化的方向和速度表现出敏感性的细胞应该对自由场中运动的声源表现出一定的敏感性。双耳搏动周期直方图的平均耳间相位的变化被用来确定平均和耳间强度的变化对细胞相位敏感性的影响。这两种形式的强度变化的影响是连续分布的。双耳节拍为研究双耳细胞的耳间相位敏感性提供了许多优点。耳间相位的动态特性可以改变，从而可以直接控制相变的速度和方向。可以以更有效的方式获得数据，因为就数据收集而言，双耳节拍比耳间延迟快约10倍。
We used the binaural beat stimulus to study the interaural phase sensitivity of inferior colliculus (IC) neurons in the cat. The binaural beat, produced by delivering tones of slightly different frequencies to the two ears, generates continuous and graded changes in interaural phase. Over 90% of the cells that exhibit a sensitivity to changes in the interaural delay also show a sensitivity to interaural phase disparities with the binaural beat. Cells respond with a burst of impulses with each complete cycle of the beat frequency. The period histogram obtained by binning the poststimulus time histogram on the beat frequency gives a measure of the interaural phase sensitivity of the cell. In general, there is good correspondence in the shapes of the period histograms generated from binaural beats and the interaural phase curves derived from interaural delays and in the mean interaural phase angle calculated from them. The magnitude of the beat frequency determines the rate of change of interaural phase and the sign determines the direction of phase change. While most cells respond in a phase-locked manner up to beat frequencies of 10 Hz, there are some cells tht will phase lock up to 80 Hz. Beat frequency and mean interaural phase angle are linearly related for most cells. Most cells respond equally in the two directions of phase change and with different rates of change, at least up to 10 Hz. However, some IC cells exhibit marked sensitivity to the speed of phase change, either responding more vigorously at low beat frequencies or at high beat frequencies. In addition, other cells demonstrate a clear directional sensitivity. The cells that show sensitivity to the direction and speed of phase changes would be expected to demonstrate a sensitivity to moving sound sources in the free field. Changes in the mean interaural phase of the binaural beat period histograms are used to determine the effects of changes in average and interaural intensity on the phase sensitivity of the cells. The effects of both forms of intensity variation are continuously distributed. The binaural beat offers a number of advantages for studying the interaural phase sensitivity of binaural cells. The dynamic characteristics of the interaural phase can be varied so that the speed and direction of phase change are under direct control. The data can be obtained in a much more efficient manner, as the binaural beat is about 10 times faster in terms of data collection than the interaural delay.