Barrett Maeve M, Doheny Emer P, Setti Annalisa, Maguinness Corrina, Foran Timothy G, Kenny Rose Anne, Newell Fiona N
School of Psychology, Trinity College, Dublin, Ireland.
Multisens Res. 2013;26(1-2):69-94. doi: 10.1163/22134808-00002412.
The current study examined the role of vision in spatial updating and its potential contribution to an increased risk of falls in older adults. Spatial updating was assessed using a path integration task in fall-prone and healthy older adults. Specifically, participants conducted a triangle completion task in which they were guided along two sides of a triangular route and were then required to return, unguided, to the starting point. During the task, participants could either clearly view their surroundings (full vision) or visuo-spatial information was reduced by means of translucent goggles (reduced vision). Path integration performance was measured by calculating the distance and angular deviation from the participant's return point relative to the starting point. Gait parameters for the unguided walk were also recorded. We found equivalent performance across groups on all measures in the full vision condition. In contrast, in the reduced vision condition, where participants had to rely on interoceptive cues to spatially update their position, fall-prone older adults made significantly larger distance errors relative to healthy older adults. However, there were no other performance differences between fall-prone and healthy older adults. These findings suggest that fall-prone older adults, compared to healthy older adults, have greater difficulty in reweighting other sensory cues for spatial updating when visual information is unreliable.
当前的研究考察了视觉在空间更新中的作用及其对老年人跌倒风险增加的潜在影响。通过在易跌倒和健康的老年人中进行路径整合任务来评估空间更新。具体而言，参与者进行了一个三角形完成任务，在该任务中，他们沿着三角形路线的两条边被引导，然后被要求在没有引导的情况下返回起点。在任务过程中，参与者可以清晰地看到周围环境（全视觉），或者通过半透明护目镜减少视觉空间信息（减少视觉）。通过计算参与者返回点相对于起点的距离和角度偏差来测量路径整合表现。还记录了无引导行走的步态参数。我们发现在全视觉条件下，所有测量指标在各小组间表现相当。相比之下，在减少视觉条件下，参与者不得不依靠内感受线索来在空间上更新他们的位置，易跌倒的老年人相对于健康老年人做出的距离误差显著更大。然而，易跌倒和健康的老年人在其他表现上没有差异。这些发现表明，与健康老年人相比，当视觉信息不可靠时，易跌倒的老年人在重新权衡其他感觉线索以进行空间更新方面有更大的困难。
