ABSTRACT

Objectives: We aimed to address whether increased task difficulty is sufficient to induce heightened conscious control and influence gait performance in older adults through the manipulations of either task difficulty or attentional focus. Method: Fifty older adults, split into high- (HR) and low-reinvestor (LR) groups, performed a walking task on a 7.4 m straight walkway in two conditions: firm level-ground surface (GW) and foam surface (FW). They subsequently performed the same walking task under two attentional focus conditions: Internal focus (IF) and External focus (EF). Electroencephalography (EEG) T3-Fz and T4-Fz coherences were used to indicate real-time conscious motor control and visual-spatial control, respectively. Results: We observed significantly higher T3-Fz and T4-Fz coherences under FW compared to GW. HR reduced their gait speed at a greater extent than LR under FW. Significantly lower T3-Fz coherence and faster gait were demonstrated under EF compared to IF. LR walked slower under IF compared to Baseline while gait speed of HR did not differ. Discussion: Visual-spatial and conscious movement processing increase as a function of task difficulty during gait. Our findings also advocate the use of external focus instructions in clinical settings, with the potential to reduce conscious control and promote movement automaticity, even in relatively complex gait tasks.

摘要

目的：我们旨在解决增加的任务难度是否足以通过对任务难度或注意力的控制来诱导老年人增强意识控制并影响步态表现。方法：将五十个老年人分成高（HR）组和低再投资（LR）组，在7.4 m直行人道上在两种情况下执行步行任务：坚固的地面（GW）和泡沫表面（FW） 。随后，他们在两个注意焦点条件下执行了相同的步行任务：内部焦点（IF）和外部焦点（EF）。脑电图（EEG）T3-Fz和T4-Fz相干性分别表示实时有意识的运动控制和视觉空间控制。结果：与GW相比，在FW下观察到的T3-Fz和T4-Fz相干性显着更高。在FW模式下，HR的步态速度比LR更大。与IF相比，EF下的T3-Fz相干性显着降低，步态更快。与基线相比，在中频条件下，LR的行走速度较慢，而HR的步态速度没有差异。讨论：视觉空间和意识运动过程随着步态中任务难度的增加而增加。我们的发现还提倡在临床环境中使用外部聚焦指令，即使在相对复杂的步态任务中，也有可能降低意识控制并提高动作自动化。