Forssberg H
Exp Brain Res. 1985;57(3):480-93. doi: 10.1007/BF00237835.
Locomotor patterns of human infants were studied during stepping in the newborn period (first two months of life), during supported locomotion (6-12 months of age) and during independent locomotion in children who just were able to walk by themselves without external support (10-18 months of age). Leg movements, pattern of muscular activity and reaction forces were studied by a computerized system. The locomotor pattern during the newborn period lacked the specific functions that are unique for human plantigrade locomotion. There was no heel strike in front of the body; the foot was placed instead on its forepart straight under the body. Hip and knee joints were hyperflexed during the whole step cycle and flexed synchronously during swing. The specific knee-ankle coordination of human adults was missing. The ankle extensors were activated prior to touch down together with other extensor muscles. There was no propulsive force. A similar immature non-plantigrade pattern recurred after an inactive period. During the subsequent period of supported locomotion there was a gradual transformation of the infantile pattern towards the plantigrade pattern continuing after establishment of independent locomotion. It is suggested that innate pattern generators in the spinal cord produce the infant stepping and also generate the basic locomotor rhythm in adults, but that neural circuits specific for humans develop late in ontogeny and transform the original, non-plantigrade motor activity to a plantigrade locomotor pattern.
研究人员对人类婴儿在新生儿期（出生后的头两个月）、扶持行走期（6至12个月大）以及刚开始能够独立行走（无需外部支撑）的儿童的独立行走期（10至18个月大）的运动模式进行了研究。通过一个计算机系统对腿部运动、肌肉活动模式和反作用力进行了研究。新生儿期的运动模式缺乏人类跖行运动所特有的特定功能。身体前方没有足跟触地；取而代之的是，脚直接放在身体正下方的前部。在整个步周期中，髋关节和膝关节过度屈曲，在摆动期同步屈曲。缺少人类成年人特有的膝 - 踝关节协调。踝关节伸肌在触地前与其他伸肌一起被激活。没有推进力。在一段不活动期后，类似的不成熟非跖行模式再次出现。在随后的扶持行走期，婴儿模式逐渐向跖行模式转变，并在独立行走确立后继续。有人提出，脊髓中的先天模式发生器产生婴儿的踏步动作，也在成年人中产生基本的运动节奏，但人类特有的神经回路在个体发育后期才发育，并将原始的非跖行运动活动转变为跖行运动模式。
