São Paulo State University (UNESP) - Campus Bauru, School of Science, Human Movement Research Laboratory (MOVI-LAB), Department of Physical Education, Graduate Program in Movement Science, Bauru, SP, Brazil.
Department of Kinesiology and Physical Education, Northern Illinois University, United States.
Gait Posture. 2021 May;86:226-232. doi: 10.1016/j.gaitpost.2021.03.026. Epub 2021 Mar 20.
People with Multiple Sclerosis (PwMS) present higher cortical activity during walking. However, the cortical activity during gait while avoiding an obstacle is still not clear.
To investigate cortical activity and gait spatial-temporal parameters in PwMS during two different gait tasks (i.e., unobstructed and obstacle avoidance).
Fifteen PwMS and 15 healthy controls (CG) were recruited. Participants performed ten trials in each gait condition, wearing a 64-electrode cap electroencephalogram (EEG) at 1024 Hz. Kinematic data were obtained through 10 Vicon® cameras at 200 Hz. EEG was analyzed through four cortical areas (frontal, motor, parietal, and occipital cortex areas) and five frequency bands (delta, theta, alpha, beta, and gamma) obtained through the power spectral density. In addition, spatial-temporal gait parameters (e.g., step length and velocity) were measured. Two-way ANOVA (group x gait condition) and MANOVA (group x gait condition) were used to compare gait and EEG parameters, respectively. One-way ANOVA was used to compare groups in the crossing phase of the obstacle avoidance condition.
PwMS presented lower step length and velocity, and higher cortical activity in frontal (beta and gamma) and parietal (gamma) cortical areas in both gait conditions compared to CG. Moreover, PwMS presented increased cortical activation (frontal and parietal) and decreased step length and velocity in obstacle avoidance compared with unobstructed gait. In addition, PwMS required more cortical resources (frontal and parietal) than CG to accomplish both gait conditions. During the obstacle avoidance task, it was further observed that PwMS positioned their feet closer to the obstacle, before and after the task, compared to CG.
PwMS demand higher cortical resources to accomplish gait tasks, mainly when it is necessary to negotiate an obstacle in the pathway. This higher cortical activity may be a compensatory mechanism to deal with damage in subcortical structures caused by multiple sclerosis.
多发性硬化症（MS）患者在行走时表现出更高的皮质活动。然而，在避免障碍物时的步态皮质活动仍不清楚。
研究多发性硬化症患者在两种不同步态任务（即无障碍和避障）下的皮质活动和步态时空参数。
招募了 15 名多发性硬化症患者和 15 名健康对照组（CG）。参与者在每个步态条件下进行了十次试验，同时佩戴一个 64 电极脑电图帽，以 1024 Hz 的频率进行记录。运动学数据通过 10 个 Vicon®摄像机以 200 Hz 的频率获取。脑电图通过四个皮质区域（额皮质、运动皮质、顶叶皮质和枕叶皮质）和五个频带（delta、theta、alpha、beta 和 gamma）进行分析，这些频带通过功率谱密度获得。此外，还测量了步态时空参数（例如，步长和速度）。使用双向方差分析（组 x 步态条件）和多元方差分析（组 x 步态条件）分别比较步态和脑电图参数。使用单向方差分析比较避障条件下穿越阶段的两组之间的差异。
与 CG 相比，多发性硬化症患者在两种步态条件下的步长和速度均较低，额皮质（beta 和 gamma）和顶叶皮质（gamma）的皮质活动较高。此外，与无障碍步态相比，多发性硬化症患者在避障时表现出更高的皮质激活（额皮质和顶叶皮质）和较低的步长和速度。此外，多发性硬化症患者完成两种步态条件需要比 CG 更多的皮质资源（额皮质和顶叶皮质）。在避障任务中，还观察到多发性硬化症患者在任务前后将脚更靠近障碍物放置，与 CG 相比。
多发性硬化症患者需要更高的皮质资源来完成步态任务，尤其是在需要在路径上避开障碍物时。这种更高的皮质活动可能是一种补偿机制，用于应对多发性硬化症引起的皮质下结构损伤。
