German Center for Neurodegenerative Diseases (DZNE), Rostock, Germany,
Department of Computer Science, Institute of Visual and Analytic Computing, University of Rostock, Rostock, Germany.
Gerontology. 2023;69(4):450-463. doi: 10.1159/000527503. Epub 2022 Dec 5.
Aging has been associated with a decline in cognitive and motor performance, often expressed in multitasking situations, which could include wayfinding. A major challenge to successful wayfinding is spatial disorientation, occurring mostly at crossings. Although gait changes have been observed in various dual-task conditions, little is known about the effect of disorientation on gait and psychophysiological response among older adults during wayfinding. The study aimed at identifying the effect of spatial disorientation on gait variability and psychophysiological response among healthy older adults during wayfinding in a controlled environment.
We analyzed data of 28 participants (age 70.8 ± 4.6, 18 female), 14 experimental and 14 controls. Participants performed a wayfinding task consisting of 14 major decision points (7 intersections) within a virtual environment (VE) projected on a 180° screen while walking on a self-paced treadmill equipped with a marker-based optical motion-capture system. The VE was held constant for the controls and manipulated for the experimental participants. Disorientation was identified based on a customized annotation scheme. Variability in gait, including the coefficient of variation (CV), was measured as the primary endpoint. Psychophysiological response measures, including heart rate variability (RMSSD) and skin conductance response (SCR), were continuously monitored as secondary endpoints and estimates of cognitive effort. Linear Mixed Effects models were applied to hypothesis-driven outcome measures extracted from decision points.
Walking speed and step length decreased when disoriented (p < 0.05), while stride time, stance time, walking speed CV, stance time CV, SCR amplitude, and SCR count increased when disoriented (p < 0.05). A higher RMSSD was associated with being disoriented at crossings (p < 0.05). SCR count was greater in the older experimental group (p < 0.001), including when disoriented (p < 0.001).
DISCUSSION/CONCLUSION: The results provide evidence for the impact of spatial disorientation on changes in gait pattern and psychophysiological response among older adults during wayfinding. Location also had implications for the effect of disorientation on gait and cognitive effort. This gives further insight into the substrates of real-world navigation challenges among older adults, with an emphasis on viable features for designing situation-adaptive interventional devices aiding independent mobility.
衰老与认知和运动表现的下降有关，这种下降通常表现在多任务情境中，其中包括寻路。成功寻路的一个主要挑战是空间定向障碍，这种障碍大多发生在十字路口。尽管在各种双任务条件下都观察到了步态变化，但对于在寻路过程中，空间定向障碍对老年人步态和心理生理反应的影响知之甚少。本研究旨在确定在受控环境中，空间定向障碍对健康老年人寻路过程中步态变异性和心理生理反应的影响。
我们分析了 28 名参与者（年龄 70.8 ± 4.6 岁，18 名女性）的数据，其中 14 名是实验组，14 名是对照组。参与者在一个虚拟环境（VE）中完成了一个寻路任务，该环境在一个 180°的屏幕上呈现，参与者在配备基于标记的光学运动捕捉系统的自步式跑步机上行走，该任务包含 14 个主要决策点（7 个十字路口）。VE 对对照组是固定的，对实验组是操纵的。定向障碍是根据一个定制的注释方案来确定的。步态的变异性，包括变异系数（CV），是作为主要终点来测量的。心率变异性（RMSSD）和皮肤电反应（SCR）等心理生理反应测量值作为认知努力的连续监测的次要终点和估计值。线性混合效应模型被应用于从决策点提取的假设驱动的结果测量。
当参与者定向障碍时，他们的行走速度和步长会下降（p < 0.05），而当他们定向障碍时，步长时间、站立时间、行走速度 CV、站立时间 CV、SCR 幅度和 SCR 计数会增加（p < 0.05）。在十字路口定向障碍时，RMSSD 更高（p < 0.05）。年龄较大的实验组的 SCR 计数更高（p < 0.001），包括定向障碍时（p < 0.001）。
讨论/结论：研究结果为空间定向障碍对老年人寻路过程中步态模式和心理生理反应变化的影响提供了证据。位置也对定向障碍对步态和认知努力的影响有影响。这进一步深入了解了老年人在现实世界导航挑战的基础，重点是为设计适应情境的干预设备提供可行的特征，以帮助独立移动。
