Institute of Biosciences, Sao Paulo State University (UNESP), Rio Claro 13506-900, Brazil.
Graduate Program in Movement Sciences, São Paulo State University (UNESP), Rio Claro 13506-900, Brazil.
Sensors (Basel). 2023 May 18;23(10):4866. doi: 10.3390/s23104866.
The neural correlates of locomotion impairments observed in people with Parkinson's disease (PD) are not fully understood. We investigated whether people with PD present distinct brain electrocortical activity during usual walking and the approach phase of obstacle avoidance when compared to healthy individuals. Fifteen people with PD and fourteen older adults walked overground in two conditions: usual walking and obstacle crossing. Scalp electroencephalography (EEG) was recorded using a mobile 64-channel EEG system. Independent components were clustered using a k-means clustering algorithm. Outcome measures included absolute power in several frequency bands and alpha/beta ratio. During the usual walk, people with PD presented a greater alpha/beta ratio in the left sensorimotor cortex than healthy individuals. While approaching obstacles, both groups reduced alpha and beta power in the premotor and right sensorimotor cortices (balance demand) and increased gamma power in the primary visual cortex (visual demand). Only people with PD reduced alpha power and alpha/beta ratio in the left sensorimotor cortex when approaching obstacles. These findings suggest that PD affects the cortical control of usual walking, leading to a greater proportion of low-frequency (alpha) neuronal firing in the sensorimotor cortex. Moreover, the planning for obstacle avoidance changes the electrocortical dynamics associated with increased balance and visual demands. People with PD rely on increased sensorimotor integration to modulate locomotion.
帕金森病（PD）患者运动障碍的神经相关性尚不完全清楚。我们研究了与健康个体相比，PD 患者在正常行走和避障的接近阶段是否存在不同的大脑皮层电活动。15 名 PD 患者和 14 名老年人在两种条件下在地面上行走：正常行走和障碍物穿越。使用移动 64 通道 EEG 系统记录头皮脑电图（EEG）。使用 k-均值聚类算法对独立分量进行聚类。测量指标包括几个频带的绝对功率和 alpha/beta 比值。在正常行走时，PD 患者的左感觉运动皮层的 alpha/beta 比值大于健康个体。在接近障碍物时，两组人都减少了运动前皮层和右侧感觉运动皮层的 alpha 和 beta 功率（平衡需求），并增加了初级视觉皮层的 gamma 功率（视觉需求）。只有 PD 患者在接近障碍物时减少了左感觉运动皮层的 alpha 功率和 alpha/beta 比值。这些发现表明，PD 影响了正常行走的皮层控制，导致感觉运动皮层中低频（alpha）神经元放电的比例增加。此外，避障的规划改变了与增加平衡和视觉需求相关的皮层电活动。PD 患者依赖增加的感觉运动整合来调节运动。
