Department of Physical Therapy and Kinesiology, University of Massachusetts Lowell, Lowell, MA, United States; New England Robotics Validation and Experimentation (NERVE) Center, University of Massachusetts Lowell, Lowell, MA, United States.
Biomedical Engineering and Biotechnology Program, University of Massachusetts Lowell, Lowell, MA, United States; Delsys Inc., Natick, MA, United States.
Gait Posture. 2022 Feb;92:167-175. doi: 10.1016/j.gaitpost.2021.11.030. Epub 2021 Nov 26.
Cognitive-walking interference is manifested when simultaneously performing a cognitive task while walking. However, majority of the dual-task walking paradigms incorporated relatively short testing trials and were focused on posing a cognitive challenge by adding a secondary cognitive task but not introducing walking perturbations.
How do healthy young adults adapt to concurrent cognitive challenges and walking perturbations in terms of task prioritization and adaptation strategies to control walking stability?
Eighteen healthy young participants walked with and without (1) continuous treadmill platform sways (Perturbed and Unperturbed walking), and (2) performing one of the cognitive tasks: visual and auditory Stroop tasks, Clock task, Paced Auditory Serial Addition Test (PASAT), and walk only. Primary outcome measures included cognitive task performance, mediolateral dynamic margins of stability (MOS), M-L local dynamic stability, stride time variability and the dual-task interference (DTI) on these measures.
Gait adjustments made during Perturbed walking did not improve walking stability but instead, showing more local instability and greater gait variability (all p < 0.001) than Unperturbed walking. Participants increased average MOS during Clock and PASAT compared to Walk Only for both Perturbed and Unperturbed walking (THSD, p < 0.05). Participants had significantly less DTI on stride time variability during Unperturbed walking than during Perturbed walking (p < 0.001). Participants also had significantly greater DTI on PASAT performance during Perturbed than during Unperturbed walking (THSD, p < 0.05) SIGNIFICANCE: Participants prioritized the walking task under a more challenging walking condition although the adjustments made during Perturbed walking were not sufficient to maintain a similar level of walking stability as Unperturbed walking. Adjustments to the cognitive-walking challenges were differed by the type of cognitive tasks. The current findings suggest that cognitive tasks involving both working memory and information processing or visuospatial recognition or attention have greater impact on gait especially during the perturbed walking condition.
认知-行走干扰表现为同时进行认知任务和行走时。然而，大多数双任务行走范式采用相对较短的测试试验，并通过添加次要认知任务来构成认知挑战，而不是引入行走干扰。
健康的年轻人如何在兼顾认知挑战和行走干扰的情况下，通过任务优先级和适应策略来控制行走稳定性？
18 名健康的年轻人分别在有无（1）连续跑步机平台晃动（干扰和非干扰行走）的情况下行走，以及（2）执行一项认知任务：视觉和听觉斯特鲁普任务、时钟任务、定时听觉连续加法测试（PASAT）和仅行走。主要观察指标包括认知任务表现、横向动态稳定性边界（MOS）、M-L 局部动态稳定性、步长时间变异性和这些测量指标上的双重任务干扰（DTI）。
干扰行走时的步态调整并未提高行走稳定性，反而表现出更大的局部不稳定性和更大的步态变异性（均 p<0.001），而不是非干扰行走。与仅行走相比，参与者在时钟和 PASAT 任务中在干扰和非干扰行走时的平均 MOS 均增加（THSD，p<0.05）。与干扰行走相比，参与者在非干扰行走时的步长时间变异性上的 DTI 显著降低（p<0.001）。参与者在干扰行走时的 PASAT 表现上的 DTI 显著高于非干扰行走（THSD，p<0.05）。
参与者在更具挑战性的行走条件下优先考虑行走任务，尽管在干扰行走时的调整不足以维持与非干扰行走相似的行走稳定性水平。认知-行走挑战的调整因认知任务的类型而异。目前的研究结果表明，涉及工作记忆和信息处理或视空间识别或注意力的认知任务对步态的影响更大，尤其是在干扰行走条件下。
