Reed M C, Blum J J
Department of Mathematics, Duke Unversity, Durham, North Carolina 27706.
J Acoust Soc Am. 1990 Sep;88(3):1442-53. doi: 10.1121/1.399721.
A structural model is proposed for the processing of interaural intensity differences by the lateral superior olive. One fundamental assumption is that the incoming excitatory projections from the ipsilateral anteroventral cochlear nucleus innervate columns of LSO neurons serially according to threshold. A second fundamental assumption is that the inhibitory innervation from the ipsilateral medial nucleus of the trapezoid body is also serially arranged according to threshold but in the opposite direction along the LSO column. Using neurophysiological and neuroanatomical data for neuronal response curves, connectional patterns, and cell and synapse numbers, the model was formulated quantitatively and implemented for machine computation. Azimuthal location is encoded by the position along the LSO column where LSO cell firing first goes to zero. Accuracy of coding was tested for three different connectional schemes, for variations in neuronal parameters, and for cell and synapse death. Encoding is shown to be independent of absolute sound level and to vary linearly with interaural intensity difference.
提出了一种用于外侧上橄榄核处理双耳强度差的结构模型。一个基本假设是，来自同侧前腹侧耳蜗核的传入兴奋性投射根据阈值依次支配外侧上橄榄核神经元柱。第二个基本假设是，来自同侧梯形体内侧核的抑制性支配也根据阈值依次排列，但沿外侧上橄榄核柱的方向相反。利用神经元反应曲线、连接模式以及细胞和突触数量的神经生理学和神经解剖学数据，对该模型进行了定量公式化并实现了机器计算。方位位置由外侧上橄榄核柱上外侧上橄榄核细胞放电首次变为零的位置编码。针对三种不同的连接方案、神经元参数变化以及细胞和突触死亡情况测试了编码准确性。结果表明，编码与绝对声级无关，并且与双耳强度差呈线性变化。
