Yough Matthew, Hanna Kacie, Yakovenko Sergiy, Gritsenko Valeriya
Department of Human Performance, West Virginia University, Morgantown, WV 26506.
Department of Biomedical Engineering, West Virginia University, Morgantown, WV 26506.
Proc Int Astronaut Congr. 2022 Sep;73.
The human motor system has evolved to perform efficient motor control in Earth's gravity. Altered gravity environments, such as microgravity and hypergravity, pose unique challenges for performing fine motor tasks with object manipulation. Altered gravity has been shown to reduce the speed and accuracy of complex manual tasks. This study aims to leverage electromyography (EMG) and virtual reality (VR) technologies to provide insights into the neuromuscular mechanism of object weight compensation. Seven healthy subjects were recruited to perform arm and hand movements, including a customized Box and Block Test with three different block weights, 0 (VR), 0.02, and 0.1 kg. EMG was recorded from 15 muscles of arm and hand while manipulating objects instrumented with force sensors to collect contact forces. Muscle co-contraction extracted from EMGs of antagonistic muscles was used as a measure of joint stiffness for each task. Results show that the co-contraction levels increased in the task with the heavy object and decreased in the VR task. This relationship suggests that the internal expectations of the object weight and the proprioceptive and haptic feedback from the contact with the object are driving the co-contraction of antagonistic muscles.
人类运动系统已经进化到能在地球重力环境下执行高效的运动控制。改变重力环境，如微重力和超重力环境，对通过物体操作执行精细运动任务提出了独特挑战。已表明改变重力会降低复杂手动任务的速度和准确性。本研究旨在利用肌电图（EMG）和虚拟现实（VR）技术，以深入了解物体重量补偿的神经肌肉机制。招募了7名健康受试者进行手臂和手部运动，包括定制的方块搭积木测试，使用三种不同的方块重量，即0（虚拟现实）、0.02和0.1千克。在操作装有力传感器以收集接触力的物体时，记录手臂和手部15块肌肉的肌电图。从拮抗肌的肌电图中提取的肌肉共同收缩用作每项任务关节刚度的度量。结果表明，重物任务中的共同收缩水平增加，而虚拟现实任务中的共同收缩水平降低。这种关系表明，物体重量的内部预期以及与物体接触时的本体感觉和触觉反馈正在驱动拮抗肌的共同收缩。
