Center for Interdisciplinary Research in Rehabilitation and Social Integration (CIRRIS), CIUSSS-CN, Quebec City, Canada.
Laboratoire Mémoire, Cerveau et Cognition (LMC2, EA 7536), Université Paris Descartes, Paris, France.
Hum Mov Sci. 2020 Feb;69:102561. doi: 10.1016/j.humov.2019.102561. Epub 2019 Dec 19.
Older adults are at greater risk of falls while descending stairs. Cognitive deficits can further influence one's ability and mild cognitive impairments (MCI) specifically affect visual attention and dual tasking behavior. The present study aimed at comparing the attentional costs at different points during the approach to and descent of a staircase between older adults with and without MCI.
Eleven older adults with MCI and twenty-three healthy older individuals without cognitive impairments were recruited. Neuropsychological tests were carried out. In addition, participants approached and descended a 5-step staircase while a simultaneous visual Stroop dual-task was randomly introduced during the approach, transition or steady state descent phases across trials. Three-dimensional kinematics and accuracy on the Stroop task were analyzed and dual task costs were calculated.
The MCI group showed deficits for visuo-spatial attention, memory and multi-tasking abilities, as well as balance and decreased confidence for falls efficacy, but not for daily activity scores. Despite such changes, this group of community-dwelling individuals with MCI presented a functional capacity to descend stairs even during divided visual attention. However, there were subtle, but significant, group differences for movement fluidity and performance on the simultaneous cognitive task, particularly during the approach and transition to descent phases. The MCI group also tended to descend slower while using the handrails more than healthy older adults.
The present cohort of community-dwelling older adults with MCI were functional, but appeared to prioritize locomotor demands over the simultaneous cognitive task in a possible "posture first" strategy to descend stairs. The present findings should be considered for developing more ecologically based clinical assessments of mobility deficits following cognitive impairments, with the approach and transition phases during stair descent as key points of focus.
老年人在下楼梯时更容易摔倒。认知缺陷会进一步影响一个人的能力,而轻度认知障碍(MCI)特别会影响视觉注意力和双重任务行为。本研究旨在比较认知正常的老年人和有 MCI 的老年人在接近和下楼梯的不同阶段的注意力成本。
招募了 11 名有 MCI 的老年人和 23 名无认知障碍的健康老年人。进行了神经心理学测试。此外,参与者在接近和下 5 级楼梯的过程中,在试验过程中随机引入了一个同时进行的视觉斯特鲁普双重任务,分别在接近、过渡或稳定下降阶段进行。分析了三维运动学和斯特鲁普任务的准确性,并计算了双重任务成本。
MCI 组在视空间注意力、记忆和多任务处理能力以及平衡和跌倒效能信心下降方面存在缺陷,但在日常活动评分方面没有缺陷。尽管存在这些变化,但这组有社区居住的 MCI 个体仍然具有下楼梯的功能能力,即使在注意力分散的情况下也是如此。然而,在运动流畅性和同时进行的认知任务表现方面,两组之间存在细微但显著的差异,尤其是在接近和过渡到下降阶段。MCI 组也倾向于在使用扶手时比健康老年人下楼梯的速度慢。
本研究中的 MCI 社区居住的老年人具有功能性,但在可能的“先姿势”策略下,他们似乎更倾向于优先考虑运动需求,而不是同时进行的认知任务,以完成下楼梯的动作。本研究结果应考虑用于开发更基于生态学的认知障碍后移动能力障碍的临床评估,以下楼梯的接近和过渡阶段为重点。