Polit A, Bizzi E
Science. 1978 Sep 29;201(4362):1235-7. doi: 10.1126/science.99813.
The experiments identify some of the processes underlying arm movements in rhesus monkeys. Three monkeys were trained to point to a target with the hand and forearm and to hold that position for about 1 second to obtain a reward. Forearm movements were performed without sight of the arm before and after bilateral dorsal rhizotomy. In both intact and deafferented animals, we unexpectedly displaced the forearm prior to movement initiation and observed that the arm moved accurately to the target. These results are relevant to the question of what is being controlled by motor commands. The controlled variable appears to be an equilibrium point between agonist and antagonist muscles. The findings suggest that the feedback system plays a major role in updating and adjusting the central programs subserving the execution of learned motor patterns.
这些实验确定了恒河猴手臂运动背后的一些过程。三只猴子经过训练，能用手和前臂指向目标，并保持该姿势约1秒钟以获取奖励。在双侧背根切断术前和术后，前臂运动都是在看不到手臂的情况下进行的。在完整和去传入神经的动物中，我们在运动开始前意外地移动了前臂，并观察到手臂能准确地移向目标。这些结果与运动指令控制的是什么这一问题相关。受控变量似乎是主动肌和拮抗肌之间的平衡点。研究结果表明，反馈系统在更新和调整支持执行习得运动模式的中枢程序方面起着主要作用。
