力回饋輔助對視覺運動協調之生理訊號變化

Abstract

本研究目的是探討力回饋輔助如何影響運動過程的效能表現、肌肉活動差異以及大腦的動態變化。受測者操控搖桿並進行軌跡跟蹤任務已完成手眼協調的任務。力回饋發生於當跟蹤軌跡誤差過大時，抵制偏移的力回饋輔助會正比於軌跡的偏差大小。在實驗一中，比較力輔助和無力輔助於運動行為能力的表現差異。在實驗二中，使用雙極電極以量測肌電訊號，以及六十四個電極的腦波帽量測腦電波訊號。並以肌電訊號能量差異、事件相關頻譜擾動(ERSP)之分析頻率在時間上變化差異了解力輔助帶來的影響。三個主要的力回饋產生的影響。第一，力輔助改善了跟蹤的運動效能特別在手臂的延展與收縮這兩個動作，但是當力輔助移除後運動效能也相對變差。第二，降低屈腕橈肌和肱二頭肌的肌肉使用力量。第三，降低α (8~12 Hz) 和 β (13~30 Hz) 頻帶的腦電圖活動。因此，在力反饋輔助下的視覺運動軌跡跟蹤任務，減輕了調控時的肌肉負擔以及加速腦波學習的形成。這項研究提供了重要的觀點，對於力反饋輔助可能是一個工具來促進和加深人們在運動學習能力。

The aim of this study was to investigate how short-term motor learning of force feedback assistance affected motor performance, muscle activity and brain dynamics. Subjects performed a trajectory tracking task of visuo-motor coordination with a joystick. Force feedback generated (maximal output 9N) by the joystick was proportional and resisted to the deviation of the tracking task. In the experiment 1 (n=30), motor behavior performance were compared between assist group and non-assist group. In the experiment 2 (n=9), electromyography (EMG) was recorded from 3 channels surface bipolar electrodes, electroencephalograph (EEG) was recorded from 64 scalp electrodes. EMG power and event-related spectral perturbation (ERSP) data were compared. There were three impacts of force feedback assistance. First, motor performance improved for the motion of flexion and extension, but no significant difference after removing the force feedback assistance. Second, lower muscle activity of flexor-carpi-radialis (FCR) and biceps brachii (BB) was performed. Third, there was a significant decreasing in alpha and beta power of EEG activity. Thus, force feedback assistance of visuo-motor trajectory tracking task was associated with decrease in EMG and attenuated alpha and beta power of EEG. This study provides important new light on the force feedback assistance may be a function as a tool to promote and deepen people’s motor learning capabilities.