Motor Control & Cognition Laboratory, Department of Human Physiology, University of Oregon, USA.
Gait Posture. 2012 Jan;35(1):159-63. doi: 10.1016/j.gaitpost.2011.09.001. Epub 2011 Oct 2.
Previous research using dual-task paradigms indicates balance-impaired older adults (BIOAs) are less able to flexibly shift attentional focus between a cognitive and motor task than healthy older adults (HOA). Shifting attention is a component of executive function. Task switch tests assess executive attention function. This multivariate study asked if BIOAs demonstrate greater task switching deficits than HOAs. A group of 39 HOA (65-80 years) and BIOA (65-87 years) subjects performed a visuo-spatial task switch. A sub-group of subjects performed a dual-task obstacle avoidance paradigm. All participants completed the Berg Balance Scale (BBS) and Timed Up and Go (TUG). We assessed differences by group for: (1) visuo-spatial task switch reaction times (switch/no-switch), and performance on the BBS and TUG. Our balance groups differed significantly on BBS score (p<.001) and switch reaction time (p=.032), but not the TUG. This confirmed our hypothesis that neuromuscular and executive attention function differs between these two groups. For our BIOA sub-group, gait velocity correlated negatively with performance on the switch condition (p=.036). This suggests that BIOA efficiency of attentional allocation in dual task settings should be further explored.
先前使用双重任务范式的研究表明，与健康老年人（HOA）相比，平衡受损的老年人（BIOA）在认知和运动任务之间灵活转移注意力焦点的能力较差。注意力转移是执行功能的一个组成部分。任务转换测试评估执行注意功能。这项多变量研究询问 BIOA 是否比 HOA 表现出更大的任务转换缺陷。一组 39 名 HOA（65-80 岁）和 BIOA（65-87 岁）受试者进行了视空间任务转换。亚组受试者进行了双重任务障碍回避范式。所有参与者都完成了伯格平衡量表（BBS）和计时起立行走测试（TUG）。我们根据组间差异评估了：（1）视空间任务转换反应时间（转换/不转换），以及 BBS 和 TUG 的表现。我们的平衡组在 BBS 评分（p<.001）和转换反应时间（p=.032）上存在显著差异，但 TUG 没有。这证实了我们的假设，即这两组之间的神经肌肉和执行注意力功能存在差异。对于我们的 BIOA 亚组，步态速度与转换条件下的表现呈负相关（p=.036）。这表明应进一步探讨 BIOA 在双重任务环境中注意力分配的效率。
