Müller K, Hömberg V, Coppenrath P, Lenard H G
Department of Pediatrics, Heinrich-Heine-University, Düsseldorf.
Neuropediatrics. 1992 Apr;23(2):82-91. doi: 10.1055/s-2008-1071318.
To analyse the influence of different "postural sets" on stance stabilizing EMG responses in children, EMG responses to toe-up tilt perturbations were recorded in 70 children between the age of 9 months and 10 years, as well as in a control group of 10 adults under different postural set conditions, using either bilateral destabilization with eyes opened, eyes closed, or introducing additional minute upper extremity support. Recordings were also made with the children seated in front of the platform with the ankle joint angle being identical to that in the standing condition. Also recordings were made after unilateral destabilization in bilateral lower leg muscles, to determine if there is a generalization of EMG response patterns to the mechanically not disturbed side. Across all age-groups the principal modulation of EMG response changes according to postural conditions was identical. Long latency (LL) EMG responses were down-regulated when additional upper extremity support was provided. LL-responses were abolished in the sitting condition. With unilateral destabilizations throughout all age-groups short latency responses were restricted to the perturbed side, whereas long latency responses could be obtained symmetrically. The proximal to distal gradient of recruitment of muscle groups, remained identical across all age-groups. The data indicate that the basic organizational principle of stance stabilizing EMG responses and their modification by postural sets remains invariant across development. This indicates that the involved organizational principles are present as soon as a child is able to stand upright and are not subject to further shaping by motor learning.
为分析不同“姿势组”对儿童站姿稳定肌电图（EMG）反应的影响，记录了70名9个月至10岁儿童以及10名成人对照组在不同姿势组条件下对足尖上抬倾斜扰动的EMG反应，这些条件包括睁眼双侧失稳、闭眼双侧失稳或增加微小的上肢支撑。还记录了儿童坐在平台前且踝关节角度与站立时相同的情况。此外，还记录了双侧小腿肌肉单侧失稳后的情况，以确定EMG反应模式是否会推广到未受机械干扰的一侧。在所有年龄组中，EMG反应根据姿势条件的主要调节方式是相同的。当提供额外的上肢支撑时，长潜伏期（LL）EMG反应被下调。在坐姿条件下，LL反应消失。在所有年龄组的单侧失稳情况下，短潜伏期反应局限于受扰动侧，而长潜伏期反应可对称获得。肌肉群募集的近端到远端梯度在所有年龄组中保持相同。数据表明，站姿稳定EMG反应的基本组织原则及其通过姿势组的调节在整个发育过程中保持不变。这表明，相关的组织原则在儿童能够直立站立时就已存在，并且不受运动学习的进一步塑造。
