PDF(Pubmed)
Abstract：
Age-related reductions in cognitive flexibility may limit modulation of control processes during systematic increases to cognitive-motor demands, exacerbating dual-task costs. In this study, behavioral and neurophysiologic changes to proactive and reactive control during progressive cognitive-motor demands were compared across older and younger adults to explore the basis for age-differences in cognitive-motor interference (CMI). 19 younger (19 - 29 years old, mean age = 22.84 +/- 2.75 years, 6 male, 13 female) and 18 older (60 - 77 years old, mean age = 67.89 +/- 4.60 years, 9 male, 9 female) healthy adults completed cued task-switching while alternating between sitting and walking on a treadmill. Gait kinematics, task performance measures, and brain activity were recorded using electroencephalography (EEG) based Mobile Brain/Body Imaging (MoBI). Response accuracy on easier trial types improved in younger, but not older adults when they walked while performing the cognitive task. As difficulty increased, walking provoked accuracy costs in older, but not younger adults. Both groups registered faster responses and reduced gait variability during dual-task walking. Older adults exhibited lower amplitude modulations of proactive and reactive neural activity as cognitive-motor demands systematically increased, which may reflect reduced flexibility for progressive preparatory and reactive adjustments over behavioral control.
摘要：
认知灵活性的年龄相关降低可能会限制在系统增加认知运动需求期间对控制过程的调节，加剧双重任务成本。在这项研究中,我们比较了老年人和年轻人在渐进性认知-运动需求过程中主动控制和反应控制的行为和神经生理变化,以探讨认知-运动干扰(CMI)年龄差异的基础.19岁以下（19-29岁，平均年龄=22.84+/-2.75岁，6男,13名女性）和18岁以上（60-77岁，平均年龄=67.89+/-4.60岁，9男,9名女性）健康的成年人在跑步机上坐着和行走之间交替完成了提示任务切换。步态运动学,任务绩效指标，使用基于脑电图（EEG）的移动脑/身体成像（MoBI）记录脑活动。更容易的试验类型的反应准确性在年轻人中得到改善，但老年人在执行认知任务时走路时不是这样。随着难度的增加,步行在老年人中引起了准确性成本，但不是年轻的成年人。在双任务行走过程中，两组都记录了更快的反应并降低了步态变异性。随着认知运动需求的系统性增加，老年人表现出主动和反应性神经活动的振幅调制较低，这可能反映了行为控制的渐进性准备和反应性调整的灵活性降低。
