Legrand Thomas, Mongold Scott J, Muller Laure, Naeije Gilles, Ghinst Marc Vander, Bourguignon Mathieu
Laboratory of Neurophysiology and Movement Biomechanics, UNI - ULB Neuroscience Institute, Université libre de Bruxelles (ULB), Brussels, Belgium.
School of Electrical and Electronic Engineering, University College Dublin (UCD), Dublin, Ireland.
Sci Rep. 2024 Dec 3;14(1):30110. doi: 10.1038/s41598-024-81865-2.
Maintaining an upright stance requires the integration of sensory inputs from the visual, vestibular and somatosensory-proprioceptive systems by the central nervous system to develop a corrective postural strategy. However, it is unclear whether and how the cerebral cortex monitors and controls postural sways. Here, we asked whether postural sways are encoded in ongoing cortical oscillations, giving rise to a form of corticokinematic coherence (CKC) in the context of standing balance. Center-of-pressure (CoP) fluctuations and electroencephalographic cortical activity were recorded as young healthy participants performed balance tasks during which sensory information was manipulated, by either removal or alteration. We found that postural sways are represented in ongoing cortical activity during challenging balance conditions, in the form of CKC at 1-6 Hz. Time delays between cortical activity and CoP features indicated that both afferent and efferent pathways contribute to CKC, wherein the brain would monitor the CoP velocity and control its position. Importantly, CKC was behaviorally relevant, as it predicted the increase in instability brought by alteration of sensory information. Our results suggest that human sensorimotor cortical areas take part in the closed-loop control of standing balance in challenging conditions. Importantly, CKC could serve as a neurophysiological marker of cortical involvement in maintaining balance.
维持直立姿势需要中枢神经系统整合来自视觉、前庭和躯体感觉 - 本体感觉系统的感觉输入，以制定纠正性姿势策略。然而，尚不清楚大脑皮层是否以及如何监测和控制姿势摆动。在此，我们探究姿势摆动是否在持续的皮层振荡中编码，从而在站立平衡的背景下产生一种形式的皮质运动连贯性（CKC）。在年轻健康参与者执行平衡任务期间，记录压力中心（CoP）波动和脑电图皮层活动，在此过程中通过移除或改变来操纵感觉信息。我们发现，在具有挑战性的平衡条件下，姿势摆动以1 - 6赫兹的CKC形式出现在持续的皮层活动中。皮层活动与CoP特征之间的时间延迟表明，传入和传出通路都对CKC有贡献，其中大脑会监测CoP速度并控制其位置。重要的是，CKC与行为相关，因为它预测了感觉信息改变带来的不稳定性增加。我们的结果表明，人类感觉运动皮层区域参与了具有挑战性条件下站立平衡的闭环控制。重要的是，CKC可作为皮层参与维持平衡的神经生理学标志物。
