Ganor I, Golani I
Brain Res. 1980 Aug 11;195(1):57-67. doi: 10.1016/0006-8993(80)90866-5.
The kinematics of the hindleg step cycle of the rat in the vertical domain is composed of 7 synergies. Additionally, a global spatiotemporal principle ensures that each segment of the leg is never displaced backwards. The concepts of flexion and extension are inadequate for the description of step kinematics. As a limb segment changes its orientation, it does so in relation to the next serially connected limb segment or else in relation to gravitation. We call these two aspects of kinematics 'movements' and 'displacements' respectively, and describe segment kinematics in these terms. Of the 7 kinematic synergies, 5 involve a specific invariant interplay between 'movements' and 'displacements'. Together with the two additional parts they form the skeleton around which the step is organized. The flexible and regulatory nature of the step is obtained by the superposition of biasable properties on top of this skeleton. These include the durations, amplitudes, and initial and final positions of movements-displacements. The formalization of the step cycle kinematics represents explicitly intralimb coordination and integration. It also specifies the demand made upon the muscular and neural background organization that mediates the kinematics in a language which is appropriate for neurophysiological investigation.
大鼠后肢在垂直平面内的步周期运动学由7种协同作用组成。此外，一个全局时空原则确保腿部的每个节段永远不会向后移位。屈伸概念不足以描述步运动学。当一个肢体节段改变其方向时，它是相对于下一个连续连接的肢体节段，或者相对于重力而改变的。我们将运动学的这两个方面分别称为“运动”和“位移”，并以此来描述节段运动学。在这7种运动学协同作用中，有5种涉及“运动”和“位移”之间特定的不变相互作用。它们与另外两个部分一起构成了步运动组织围绕的框架。步运动的灵活性和调节性是通过在这个框架之上叠加可偏移特性而获得的。这些特性包括运动-位移的持续时间、幅度以及起始和终末位置。步周期运动学的形式化明确表示了肢体内部的协调与整合。它还以一种适合神经生理学研究的语言，规定了对介导运动学的肌肉和神经背景组织的要求。
