Krishnan Chandramouli, Augenstein Thomas E, Claflin Edward S, Hemsley Courtney R, Washabaugh Edward P, Ranganathan Rajiv
Department of Physical Medicine and Rehabilitation, Michigan Medicine.
Department of Robotics, University of Michigan.
medRxiv. 2024 Apr 3:2024.04.01.24304938. doi: 10.1101/2024.04.01.24304938.
The ability to relearn a lost skill is critical to motor recovery after a stroke. Previous studies indicate that stroke typically affects the processes underlying motor control and execution but not the learning of those skills. However, these prior studies could have been confounded by the presence of significant motor impairments and/or have not focused on motor acuity tasks (i.e., tasks focusing on the quality of executed actions) that have direct functional relevance to rehabilitation.
Twenty-five participants (10 stroke; 15 controls) were recruited for this prospective, case-control study. Participants learned a novel foot-trajectory tracking task on two consecutive days while walking on a treadmill. On day 1, participants learned a new gait pattern by performing a task that necessitated greater hip and knee flexion during the swing phase of the gait. On day 2, participants repeated the task with their training leg to test retention. An average tracking error was computed to determine online and offline learning and was compared between stroke survivors and uninjured controls.
Stroke survivors were able to improve their tracking performance on the first day (p=0.033); however, the amount of learning in stroke survivors was lower in comparison with the control group on both days (p≤0.05). Interestingly, the offline gains in motor learning were higher in stroke survivors when compared with uninjured controls (p=0.011).
The results suggest that even high-functioning stroke survivors may have difficulty acquiring new motor skills related to walking, which may be related to the underlying neural damage caused at the time of stroke. Furthermore, it is likely that stroke survivors may require longer training with adequate rest to acquire new motor skills, and rehabilitation programs should target motor skill learning to improve outcomes after stroke.
重新学习已丧失技能的能力对于中风后的运动恢复至关重要。先前的研究表明，中风通常会影响运动控制和执行的潜在过程，但不会影响这些技能的学习。然而，这些先前的研究可能因存在明显的运动障碍而受到混淆，和/或没有关注与康复有直接功能相关性的运动敏锐度任务（即专注于执行动作质量的任务）。
招募了25名参与者（10名中风患者；15名对照组）进行这项前瞻性病例对照研究。参与者在跑步机上行走时连续两天学习一项新的足部轨迹跟踪任务。在第1天，参与者通过执行一项在步态摆动期需要更大程度的髋部和膝部屈曲的任务来学习一种新的步态模式。在第2天，参与者用其训练腿重复该任务以测试记忆保持情况。计算平均跟踪误差以确定在线和离线学习情况，并在中风幸存者和未受伤的对照组之间进行比较。
中风幸存者在第一天能够提高其跟踪性能（p = 0.033）；然而，与对照组相比，中风幸存者在两天中的学习量均较低（p≤0.05）。有趣的是，与未受伤的对照组相比，中风幸存者在运动学习方面的离线增益更高（p = 0.011）。
结果表明，即使是功能良好的中风幸存者在获取与行走相关的新运动技能方面也可能存在困难，这可能与中风时造成的潜在神经损伤有关。此外，中风幸存者可能需要更长时间的训练并给予足够的休息来获取新的运动技能，并且康复计划应针对运动技能学习以改善中风后的结果。
