Kim Seung-Jae, Kayitesi Marie Aimee, Chan Amy, Graham Kimberli
Department of Biomedical Engineering, The Gordon and Jill Bourns College of Engineering, California Baptist University, 8432 Magnolia Avenue, Riverside, CA, 92504, USA.
Appl Psychophysiol Biofeedback. 2017 Jun;42(2):107-115. doi: 10.1007/s10484-017-9358-0.
The incorporation of real-time visual feedback during gait rehabilitation can improve the efficacy of training. Our prior work demonstrated that the imposed distortion of simple visual feedback information of step lengths entails an unintentional adaptive process in the subjects' spatial gait pattern, thereby suggesting the important role of implicit learning in the context of gait rehabilitation that employs visual feedback. The purpose of this study was to investigate whether the removal of a portion of visual feedback information-after it had initially been provided-had any impact on gait symmetry. Eighteen healthy subjects walked on a treadmill for 10-min periods at their preferred walking speed and at a slower walking speed (1.3 mph) during the experimental trials, in which two simple vertical bars corresponding to subject's right and left step length were displayed on a computer screen. Halfway through the trial, one of the bars was removed from the visual feedback via random selection. Subjects were instructed to continually walk normally and also look at the visual feedback until the trials were completed. The changes in step length symmetry ratio were computed and analyzed. We found that displaying only one side of visual feedback influenced subjects to spontaneously modulate gait symmetry away from the baseline, and also that the amount of modulated gait symmetry slightly increased when their walking speed decreased. The changes in gait symmetry occurred by producing either longer right steps produced than left steps or vice versa, but we were unable to find any correlation between side of removal (right or left side) and the different types of trend in response. This warrants further investigation in a study with a larger population. Nonetheless, the results of this study demonstrated the effect of partial absence of visual feedback on changes in step symmetry, and that the perturbation of visual information caused implicit (unintentional) motor processes. A gait training procedure involving a novel way of perturbing visual feedback, such as partial absence of visual feedback tested in this study, may be of value in gait rehabilitation by driving more efficient motor adaptations.
在步态康复过程中加入实时视觉反馈可以提高训练效果。我们之前的研究表明，对步长的简单视觉反馈信息进行人为扭曲会使受试者的空间步态模式发生无意的适应性变化，从而表明在采用视觉反馈的步态康复中，内隐学习具有重要作用。本研究的目的是调查在最初提供视觉反馈信息后，去除一部分该信息是否会对步态对称性产生影响。在实验过程中，18名健康受试者以他们偏好的步行速度和较慢的步行速度（1.3英里/小时）在跑步机上行走10分钟，期间计算机屏幕上会显示对应受试者左右步长的两根简单垂直条。试验进行到一半时，通过随机选择从视觉反馈中移除其中一根条。受试者被要求继续正常行走并观看视觉反馈，直到试验结束。计算并分析步长对称率的变化。我们发现，仅显示一侧的视觉反馈会促使受试者自发地调整步态对称性，使其偏离基线，并且当他们的步行速度降低时，步态对称性的调整量会略有增加。步态对称性的变化是通过产生比左侧步长更长的右侧步长或反之来实现的，但我们未能发现移除条的一侧（右侧或左侧）与不同类型的反应趋势之间存在任何关联。这需要在更大规模的人群研究中进一步调查。尽管如此，本研究结果证明了部分缺失视觉反馈对步长对称性变化的影响，并且视觉信息的扰动引发了内隐（无意）运动过程。一种涉及以新颖方式扰动视觉反馈的步态训练程序，例如本研究中测试的部分缺失视觉反馈，可能通过推动更有效的运动适应而在步态康复中具有价值。
