Timing of secondary vestibular neuron responses to a range of rotational head movements.
Timing of secondary vestibular neuron responses to a range of rotational head movements.
复制标题
次级前庭神经元对一系列旋转头部运动的反应时间。
DOI：
10.1007/s004220050456
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发表时间：
1998
期刊：
影响因子：
--
通讯作者：
McCollum,G
中科院分区：
文献类型：
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作者：
Holly,JE;McCollum,G
次级前庭神经元对头部运动表现出各种各样的反应，每个次级神经元的反应取决于会聚到其上的特定初级传入，从而以分布式方式记录单个头部运动。本文主要研究水平轴旋转运动时，传入会聚对次级神经元反应调制相对时间的影响。特别地，感兴趣的神经元是从支配垂直半规管的传入神经接收输入的神经元，并且感兴趣的运动是具有围绕一个垂直半规管轴的正弦分量和围绕另一个近似正交的垂直半规管轴的正弦分量的运动。在这些条件下，本研究表明，两个或更多个次级神经元可能具有不同的相对反应时间（即，放电率周期性调制的不同相对相位）用于不同的头部运动，以及神经元针对不同运动切换其响应顺序。对于特定的头部运动，这些相同的神经元将同步响应。从神经系统的角度来看，神经元反应的相对时间可以告诉正在发生的运动，但有一定的限制，如本文所讨论的。这里显示的是，在那些头部运动中，旋转的两个分量可以相对于彼此处于任何相位并且具有任何相对幅度，仅仅两个神经元的同相响应不能识别单个运动。两个神经元对一个运动的反应是同相的，那么它们对整个运动范围的反应必然是同相的;因此，在这个范围内的所有运动都是反应等价的，也就是说，这对神经元不能区分这两个运动。另一方面，三个神经元的同相反应可以识别单个运动，用于初级传入会聚的某些模式。
Secondary vestibular neurons exhibit a wide variety of responses to a head movement, with the response of each secondary neuron depending upon the particular primary afferents converging onto it. A single head movement is thereby registered in a distributed manner. This paper focuses on implications of afferent convergence to the relative timing of secondary neuron response modulation during rotational movements about a combination of horizontal axes. In particular, the neurons of interest are those that receive input from afferents innervating the vertical semicircular canals, and the movements of interest are those that have a sinusoidal component about one vertical canal axis and a sinusoidal component about another, approximately orthogonal, vertical canal axis. Under these conditions, the present research shows that it is possible for two or more secondary neurons to have a different relative timing of response (i.e., different relative phase of the periodic modulation in firing rate) for different head movements, and for the neurons to switch their order of response for different movements. For particular head movements, those same neurons will respond in phase. From the point of view of the nervous system, the relative timing of neuron responses may tell which movement is taking place, but with certain restrictions as discussed in the present paper. Shown here is that, among those head movements for which the two components of rotation may be at any phase relative to one another and have any relative amplitude, an in-phase response of just two neurons cannot identify a single motion. Two neurons that respond in phase for one motion must respond in phase for an entire range of motions; all motions in that range are thus response-equivalent, in the sense that the pair of neurons cannot distinguish between the two motions. On the other hand, an in-phase response of three neurons can identify a single motion, for certain patterns of primary afferent convergence.