Deliagina T G, Arshavsky Y I, Orlovsky G N
The Nobel Institute of Neurophysiology, Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden.
Nature. 1998 May 14;393(6681):172-5. doi: 10.1038/30251.
The main function of postural nervous mechanisms in different species, from mollusc to man, is to counteract the force of gravity and stabilize body orientation in space. Here we investigate the basic principles of postural control in a simple animal model, the marine mollusc Clione limacina. When swimming, C. limacina maintains its vertical orientation because of the activity of the postural neuronal network. Driven by gravity-sensing organs (statocysts), the network causes postural corrections by producing tail flexions. To understand how this function occurs, we studied network activity by using a new method. We used an in vitro preparation that consisted of the central nervous system isolated with the statocysts. Output signals from the network (electrical activity of tail motor neurons) controlled an electrical motor which rotated the preparation in space. We analysed the activity of individual neurons involved in postural stabilization under opened or closed feedback loop. When we closed this artificial feedback loop, the network stabilized the vertical orientation of the preparation. This stabilization is based on the tendency of the network to minimize the difference between the activities of the two antagonistic groups of neurons, which are driven by orientation-dependent sensory inputs.
从软体动物到人类，不同物种中姿势神经机制的主要功能是抵消重力并稳定身体在空间中的方向。在此，我们在一种简单的动物模型——海洋软体动物海天使（Clione limacina）中研究姿势控制的基本原理。游泳时，由于姿势神经元网络的活动，海天使保持其垂直方向。受重力感应器官（平衡囊）驱动，该网络通过产生尾部弯曲来进行姿势校正。为了解此功能是如何发生的，我们使用一种新方法研究了网络活动。我们采用了一种体外制备方法，即将中枢神经系统与平衡囊分离。网络的输出信号（尾部运动神经元的电活动）控制一个电动马达，该马达使制备物在空间中旋转。我们分析了在开环或闭环反馈条件下参与姿势稳定的单个神经元的活动。当我们闭合这个人工反馈环时，网络稳定了制备物的垂直方向。这种稳定基于网络使由方向依赖性感觉输入驱动的两组拮抗神经元活动之间的差异最小化的趋势。
