Schwartzman R J
Ann Neurol. 1978 Sep;4(3):234-44. doi: 10.1002/ana.410040308.
Ten Macaca mulatta monkeys were operantly conditioned to perform three motor paradigms designed to evaluate single and combination finger movements. Eight of these monkeys were retested after left medullary pyramidotomy; 2 monkeys underwent left medullary pyramidotomy prior to conditioning. All animals were tested for three years after operation. Monkeys with a completely sectioned medullary pyramid could, with time, perform difficult motor paradigms that required: (1) both individual and combination finger movements; (2) proximal upper extremity motor control; (3) thumb and index finger pincer grasp; and (4) the ability to preprogram and then execute a precision hand movement. The greater the extent of pyramidal tract destruction, the longer the time necessary for recovery of both discrete finger movement and pincer grasp, the greater the effort needed to attain recovery of hand function, and the weaker the affected musculature. The 2 animals in which pyramidotomy of at least 70% of the tract preceded efforts at operant conditioning learned and performed difficult motor paradigms. In all animals, neurological examination revealed that the most enduring and functionally most important deficit that interferes with hand function following pyramidotomy is loss of contactual hand orienting responses and failure of reflex sensorimotor adjustments.
十只恒河猴接受了操作性条件反射训练，以执行三种旨在评估单个手指运动和手指组合运动的运动范式。其中八只猴子在左侧延髓锥体束切断术后接受了重新测试；两只猴子在训练前接受了左侧延髓锥体束切断术。所有动物在手术后都接受了三年的测试。延髓锥体完全切断的猴子，随着时间的推移，能够执行需要以下能力的困难运动范式：（1）单个手指运动和手指组合运动；（2）近端上肢运动控制；（3）拇指和食指捏取；（4）预先编程然后执行精确手部运动的能力。锥体束破坏的程度越大，离散手指运动和捏取恢复所需的时间就越长，恢复手部功能所需的努力就越大，受影响的肌肉组织就越弱。在至少70%的锥体束被切断后才进行操作性条件反射训练的两只动物学会并执行了困难的运动范式。在所有动物中，神经学检查显示，延髓锥体束切断术后干扰手部功能的最持久且功能上最重要的缺陷是手部接触定向反应的丧失和反射性感觉运动调节的失败。
