Forssberg H, Grillner S, Halbertsma J
Acta Physiol Scand. 1980 Mar;108(3):269-81. doi: 10.1111/j.1748-1716.1980.tb06533.x.
Kittens were subjected to a complete transection of the spinal cord (Th 10--12) 1--2 weeks after birth. A few days after the operation they could perform alternating limb movements and somewhat later walking movements with their hindlimbs on a treadmill. The stepcycle of the hindlimbs could be divided into a flexion phase (F) and a first (E1), second (E2) and third (E3) extension phase. The duration of the support phase decreased markedly with treadmill velocity while the swing phase decreased to a much smaller extent. The pattern of electromyographical activity in hip, knee, ankle and toe muscles during treadmill locomotion was very similar to that of the intact cat. This related to both the timing and the general shape of locomotor bursts. The extensor muscles were thus activated well before the placement of the foot and able to produce enough force to support the body. The propulsive thrust in each step was, however, decreased and the animals showed more severe deficits particularly in their equilibrium control. It is concluded, however, that neural networks in the spinal cord (with its peripheral inflow intact but without supraspinal influences) have the capacity to generate a specific and detailed locomotor pattern.
出生后1至2周，将小猫的脊髓（胸10 - 12）完全横断。术后几天，它们能够进行交替性肢体运动，一段时间后，后肢能在跑步机上做出行走动作。后肢的步周期可分为屈曲期（F）和第一伸展期（E1）、第二伸展期（E2）以及第三伸展期（E3）。支撑期的持续时间随跑步机速度显著缩短，而摆动期的缩短幅度则小得多。在跑步机运动过程中，髋部、膝部、踝部和趾部肌肉的肌电图活动模式与正常猫非常相似。这与运动爆发的时间和总体形态有关。因此，伸肌在足部着地前就被很好地激活，能够产生足够的力量来支撑身体。然而，每一步的推进力都有所下降，动物表现出更严重的缺陷，尤其是在平衡控制方面。然而，可以得出结论，脊髓中的神经网络（其外周输入完整，但无脊髓以上的影响）有能力产生特定且详细的运动模式。
