Department of Epidemiology, University of Pittsburgh, Pittsburgh, PA, USA.
Division of Geriatric Medicine, University of Pittsburgh, Pittsburgh, PA, USA.
Aging Clin Exp Res. 2024 Feb 17;36(1):43. doi: 10.1007/s40520-023-02666-7.
Higher prefrontal cortex (PFC) activation while walking may indicate reduced gait automaticity.
We examine whether PFC activation during walking improves after training in older adults at risk for mobility disability.
Forty-two adults aged ≥ 65 participated in a randomized clinical trial (NCT026637780) of a 12-week timing and coordination physical therapy intervention to improve walking (n = 20 intervention, n = 22 active control). PFC activation was measured by functional near-infrared spectroscopy (fNIRS) during four walking tasks over 15 m, each repeated 4 times: even surface walking, uneven surface walking, even dual-task, uneven dual-task; dual-task was reciting every other letter of the alphabet while walking. Gait speed and rate of correct letter generation were recorded. Linear mixed models tested between arm differences in change of fNIRS, gait speed, and letter generation from baseline to follow-up (12-week, 24-week, and 36-week).
Intervention arms were similar in mean age (74.3 vs. 77.0) and baseline gait speed (0.96 vs. 0.93 m/s). Of 24 comparisons of between arm differences in the fNIRS signals, only two were significant which were not supported by differences at other follow-up times or on other tasks. Gait speed, particularly during dual-task conditions, and correct letter generation did improve post-intervention but improvements did not differ by arm.
After training, PFC activation during walking generally did not improve and did not differ by intervention arm. Improvements in gait speed without increased PFC activation may point toward more efficient neural control of walking.
在行走时，前额皮质（prefrontal cortex，PFC）的活跃度增加可能表明步态的自发性降低。
我们研究了在有行走障碍风险的老年人中，经过 12 周的定时和协调物理治疗干预训练后，行走时 PFC 的活跃度是否会提高。
42 名年龄≥65 岁的成年人参与了一项为期 12 周的定时和协调物理治疗干预（NCT026637780）的随机临床试验，以改善行走能力（n=20 例干预组，n=22 例活跃对照组）。在行走 15 米的四个任务中，通过功能近红外光谱（functional near-infrared spectroscopy，fNIRS）测量 PFC 激活，每个任务重复 4 次：在平坦表面行走、在不平坦表面行走、在平坦表面进行双重任务、在不平坦表面进行双重任务；双重任务是在行走时背诵字母表中的每个字母。记录行走速度和正确字母生成的速度。线性混合模型测试了从基线到随访（12 周、24 周和 36 周）时，fNIRS、行走速度和字母生成变化的手臂间差异。
干预组在平均年龄（74.3 岁比 77.0 岁）和基线行走速度（0.96 米/秒比 0.93 米/秒）方面相似。在 24 次手臂间 fNIRS 信号差异的比较中，只有两次有显著差异，但在其他随访时间或其他任务中没有差异支持。行走速度，特别是在双重任务条件下，以及正确字母生成确实在干预后有所提高，但手臂间没有差异。
经过训练，行走时 PFC 的激活通常没有改善，也没有因干预手臂而不同。行走速度的提高而没有增加 PFC 的激活，可能指向行走的神经控制更有效。
