Department of Nutrition, Exercise and Sports, University of Copenhagen, Copenhagen, Denmark.
Department of Kinesiology, University of Massachusetts, Amherst, MA, USA.
Neurobiol Aging. 2019 Jun;78:29-41. doi: 10.1016/j.neurobiolaging.2019.02.005. Epub 2019 Feb 13.
We investigated age-related differences in corticospinal control of muscle activity during normal and visually guided (VG) walking. Young (n = 15, 22.1 ± 1.7 years) and older (n = 15, 68.3 ± 2.7 years) participants performed normal walking and VG walking requiring precise foot placement based on visual cues. Coherence analysis was used to quantify coupling between electroencephalography and electromyography from the anterior tibial muscle (corticomuscular) and between the 2 ends of the anterior tibial muscle (intramuscular) at 15-50 Hz during the swing phase of walking as markers of corticospinal activity. Our results indicated that corticomuscular and intramuscular coherence was lower in older compared to young participants during both tasks. In addition, coherence was generally greater during VG than during normal walking across age groups, although during late swing, older participants drove several of the observed task-related coherence increases. Performance on the VG task was lower in older compared to young participants and was correlated with task-related corticomuscular coherence modulations within the older group. These results suggest age-related differences in the corticospinal control of walking, with possible implications for precision control of foot placement based on visual information.
我们研究了正常和视觉引导（VG）行走过程中皮质脊髓对肌肉活动的控制随年龄的变化差异。年轻组（n=15，22.1±1.7 岁）和老年组（n=15，68.3±2.7 岁）参与者进行了正常行走和 VG 行走，VG 行走需要根据视觉线索精确放置脚。相干性分析用于量化行走摆动相期间脑电图和胫骨前肌（皮质肌）之间（皮质脊髓）以及胫骨前肌 2 端之间（肌内）的耦合（15-50 Hz）作为皮质脊髓活动的标志物。我们的结果表明，在这两种任务中，与年轻参与者相比，老年参与者的皮质肌和肌内相干性较低。此外，在跨年龄组的 VG 行走过程中，通常比正常行走时相干性更高，尽管在后期摆动时，老年参与者驱动了观察到的与任务相关的相干性增加中的几个。与年轻参与者相比，老年参与者在 VG 任务上的表现较差，并且与老年参与者中与任务相关的皮质脊髓相干性调制相关。这些结果表明，皮质脊髓对行走的控制存在与年龄相关的差异，这可能对基于视觉信息的精确足部放置控制有影响。
