Kiemel Tim, Zhang Yuanfen, Jeka John J
Department of Kinesiology, University of Maryland, College Park, MD 20742-2611, USA.
J Mot Behav. 2011;43(3):237-46. doi: 10.1080/00222895.2011.568991.
To control upright stance, the human nervous system must estimate the movements of multiple body segments based on multisensory information. To investigate how visual information contributes to such multisegmental estimation, participants were exposed to 3 types of visual-scene movement: translation in the anteroposterior direction, rotation about the ankle joint, and rotation about the hip joint. Trunk and leg responses were larger for rotational than for translational movements, but only at lower stimulus frequencies. Based on a feedback-control theoretical framework, these results indicated that visual inputs distinguish between translation and rotation of the head. Also, visual condition effects were similar for the leg and trunk segments, suggesting a control strategy with a single control signal that determines the activation of all muscles.
为了控制直立姿势，人类神经系统必须基于多感官信息来估计多个身体节段的运动。为了研究视觉信息如何有助于这种多节段估计，让参与者接触3种类型的视觉场景运动：前后方向的平移、绕踝关节的旋转以及绕髋关节的旋转。对于旋转运动，躯干和腿部的反应比平移运动时更大，但仅在较低的刺激频率下如此。基于反馈控制理论框架，这些结果表明视觉输入能够区分头部的平移和旋转。此外，腿部和躯干节段的视觉条件效应相似，这表明存在一种控制策略，即使用单一控制信号来确定所有肌肉的激活。
