本研究基于经典快速举臂试验与落球试验范式,采用表面肌电信号分析技术,研究内、外姿势干扰强度的心理预期对腰部姿势肌肉和上肢动作肌肉预期姿势调节(APAs)和补偿姿势调节(CPAs)的影响,探讨中枢神经系统(CNS)对内、外姿势干扰的控制策略。20名健康受试者先后完成不同负荷强度的快速举臂试验和落球试验,同步采集腰部竖脊肌、腰部多裂肌和上肢肱二头肌的表面肌电信号,计算肌肉预激活时间和APAs与CPAs积分肌电值,观察内、外姿势干扰强度的心理预期对中枢APAs和CPAs控制机制的影响。结果显示内部姿势干扰条件下,干扰强度的心理预期对腰部多裂肌、腰部竖脊肌和上肢肱二头肌的APAs强度有显著影响,而对预激活时间和CPAs强度无显著影响;外部姿势干扰条件下,干扰强度的心理预期对腰部多裂肌、腰部竖脊肌和肱二头肌的APAs强度有显著影响,对肱二头肌和腰部多裂肌预激活时间有显著影响,而对CPAs强度无显著影响。突发可预期姿势干扰条件下姿势的快速反应是一个由CNS主导的神经肌肉运动控制过程。受姿势干扰强度心理预期的影响,CNS对内、外突发姿势干扰条件下腰部姿势肌肉的活动采取了不同的控制策略。在内部姿势干扰条件下,干扰刺激发生时间明确,CNS主要通过对APAs强度的调节来实现姿势肌肉的优化控制;而在外部姿势干扰条件下,干扰刺激时间不明确,CNS则通过对局部稳定肌APAs预激活时间以及局部稳定肌和整体稳定肌APAs强度的双重调节实现姿势肌肉的优化控制。干扰强度的心理预期对姿势肌肉APAs和CPAs的作用表明,心理预期效应主要源自于CNS对局部和整体稳定肌APAs控制机制的调制。
In response to sudden posture perturbation, two different neural control strategies in central nervous system are used, named anticipatory postural adjustments (APAs) and compensatory postural adjustments (CPAs). Previous studies have identified associations between psychological expectations of posture perturbation and the intensity of APAs and CPAs. However, it''s unclear whether these associations are consistent with different experiment paradigm and perturbations from different sources. This study aimed to examine the psychological predictive effect of sudden posture perturbation magnitude on the APAs and CPAs by which CNS acts on focal muscles and lumbar posture muscles. Arm-raising test and Ball-hitting test were performed with surface electromyography signal analysis. 20 healthy subjects voluntarily participated in the studies. In the Arm-raising test, they rapidly raise arms with a load of 0 kg/1 kg/2 kg in both hands. In the Ball-hitting test, they caught a ball fell