Worcester Polytechnic Institute, Worcester, MA, USA.
Liberating Technologies, Inc., Holliston, MA, USA.
J Electromyogr Kinesiol. 2023 Apr;69:102753. doi: 10.1016/j.jelekin.2023.102753. Epub 2023 Jan 30.
Bilateral movement is widely used for calibration of myoelectric prosthesis controllers, and is also relevant as rehabilitation therapy for patients with motor impairment and for athletic training. Target tracking and/or force matching tasks can be used to elicit such bilateral movement. Limited descriptive accuracy data exist in able-bodied subjects for bilateral target tracking or dominant vs non-dominant dynamic force matching tasks requiring more than one degree of freedom (DoF). We examined dynamic trajectory (0.75 Hz band-limited, white, uniform random) constant-posture, hand open-close, wrist pronation-supination target tracking and matching tasks. Tasks were normalized to maximum voluntary contraction (MVC), spanning a ± 30% MVC force range, in four 1-DoF and 2-DoF tasks: (1, 2) unilateral dominant limb tracking with/without visual feedback, and (3, 4) bilateral dominant/non-dominant limb tracking with mirror visual feedback. In 12 able-bodied subjects, unilateral tracking error with visual feedback averaged 10-15 %MVC, but up to 30 %MVC without visual feedback. Bilateral matching error averaged ∼10 %MVC and was affected little by visual feedback type, so long as feedback was provided. In 1-DoF bilateral tracking, the dominant side had statistically lower error than the non-dominant side. In 2-DoF bilateral tracking, the side providing mirror visual feedback exhibited lower error than the opposite side. In 2-DoF tasks (assumed to be more challenging than their constituent 1-DoF tracking tasks), hand grip force errors grew disproportionately larger than those of each wrist DoF. In unilateral 1-DoF tasks, both hand vs target and wrist vs target latency averaged 250-350 ms. In unilateral 2-DoF tasks, wrist vs target latency also averaged 250-350 ms, while hand vs target latency averaged > 500 ms. These results provide guidance on bilateral 2-DoF hand-wrist performance in target tracking, and dominant vs non-dominant force matching tasks.
双侧运动被广泛用于肌电假体控制器的校准，也与运动障碍患者的康复治疗和运动训练相关。目标跟踪和/或力匹配任务可用于引发这种双侧运动。对于需要超过一个自由度 (DoF) 的双侧目标跟踪或优势与非优势动态力匹配任务，在健全受试者中存在有限的描述准确性数据。我们检查了动态轨迹（0.75 Hz 带宽限制，白色，均匀随机）恒位、手张开-闭合、腕部旋前-旋后目标跟踪和匹配任务。任务归一化到最大自主收缩 (MVC)，跨越±30% MVC 力范围，在四个 1-DoF 和 2-DoF 任务中：(1,2)单侧优势肢体跟踪，有/无视觉反馈，以及(3,4)双侧优势/非优势肢体跟踪，具有镜像视觉反馈。在 12 名健全受试者中，具有视觉反馈的单侧跟踪误差平均为 10-15%MVC，但在没有视觉反馈的情况下高达 30%MVC。双侧匹配误差平均为 10%MVC，并且只要提供反馈，就很少受到视觉反馈类型的影响。在 1-DoF 双侧跟踪中，优势侧的误差明显低于非优势侧。在 2-DoF 双侧跟踪中，提供镜像视觉反馈的一侧的误差明显低于另一侧。在 2-DoF 任务中（假设比其组成的 1-DoF 跟踪任务更具挑战性），手抓力误差不成比例地大于每个手腕 DoF 的误差。在单侧 1-DoF 任务中，手与目标和手腕与目标的潜伏期平均为 250-350ms。在单侧 2-DoF 任务中，手腕与目标的潜伏期也平均为 250-350ms，而手与目标的潜伏期平均为>500ms。这些结果为双侧 2-DoF 手-腕在目标跟踪和优势与非优势力匹配任务中的性能提供了指导。
