Cortical and sensory control of standing balance

站立平衡的皮层和感觉控制

• 批准号: RGPIN-2017-06632
• 负责人: DALTON, BRIAN
• 金额: $ 4.81万
• 依托单位: University of British Columbia
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2022
• 资助国家: 加拿大
• 起止时间: 2022-01-01 至 2023-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=761795
• 关键词: Cortical; sensory; control; standing; balance

Standing balance entails rapid processing and integration of sensorimotor signals within the central and peripheral nervous system, which include information from vestibular, visual, and somatosensory cues. Upright balance control is typically an afterthought and its complexity and importance is only realized once the neuromuscular system undergoes an insult or chronic deterioration. With adult aging, the neuromuscular system endures degenerative changes, characterized by muscle atrophy and declines in structure and function. Despite much research on standing balance in older adults, many studies do not provide mechanistic insight into the cortical and sensorimotor control necessary for standing. The aged neuromuscular system offers an excellent model to further our understanding of sensorimotor adaptations through investigation into the integration and transformation of cortical and sensorimotor signals that modulate balance in a chronically-altered and compromised state. An effective means to evaluate the integrity of the neuromuscular system is to stress it acutely through an intervention such as muscle fatigue. Yet, little is known about how fatigue affects the sensorimotor control of standing. Thus, the LONG-TERM OBJECTIVE of my research program is to better understand the fundamental processes related to the sensorimotor control of standing balance and movement. Over the next five-years, my lab will address two short-term research objectives that will contribute to the achievement of my long-term objective. The first SHORT-TERM OBJECTIVE will identify how acute (i.e., fatigue) and chronic (i.e., adult aging) adaptations alter the vestibular control of standing balance. We have recently reported an age-related central gain enhancement for vestibulomotor and vestibular perception pathways. However, the specific mechanisms underlying this compensatory increase in central sensitivity and its relevance to the sensorimotor control of balance is unclear, and results from my research group will provide insight into the underlying factors related to the age-related alterations of the vestibular control of balance. The second SHORT-TERM OBJECTIVE will identify mechanisms related to the cortical contributions to standing through exploiting natural adult aging and fatigue. For young, cortical involvement in maintaining standing balance is limited. However, the cortical contributions to balance is likely enhanced with natural adult aging, but this concept has not been addressed thoroughly. My research group will identify mechanisms related to the cortical control of standing balance using neuromuscular fatigue and a chronically-adapted state. The proposed experiments will offer valuable insight into how cortical- and sensory- (i.e., vestibular) related mechanisms modulate standing balance control by exploiting acutely- and chronically-altered states.

站立平衡需要中枢和周围神经系统内感觉运动信号的快速处理和整合，其中包括来自前庭、视觉和体感线索的信息。 直立平衡控制通常是事后才想到的，只有当神经肌肉系统遭受损伤或慢性恶化时，才会意识到其复杂性和重要性。 随着成年人的衰老，神经肌肉系统会经历退行性变化，其特征是肌肉萎缩以及结构和功能下降。 尽管对老年人的站立平衡进行了大量研究，但许多研究并未提供对站立所需的皮质和感觉运动控制的机制见解。 老化的神经肌肉系统提供了一个很好的模型，通过研究皮质和感觉运动信号的整合和转化来进一步了解感觉运动适应，这些信号在长期改变和受损的状态下调节平衡。 评估神经肌肉系统完整性的有效方法是通过肌肉疲劳等干预措施对其施加剧烈压力。 然而，人们对疲劳如何影响站立的感觉运动控制知之甚少。 因此，我的研究计划的长期目标是更好地理解与站立平衡和运动的感觉运动控制相关的基本过程。 在接下来的五年中，我的实验室将解决两个短期研究目标，这将有助于实现我的长期目标。 第一个短期目标将确定急性（即疲劳）和慢性（即成人衰老）适应如何改变前庭对站立平衡的控制。 我们最近报道了与年龄相关的前庭运动和前庭感知通路的中枢增益增强。 然而，这种中枢敏感性代偿性增加的具体机制及其与平衡感觉运动控制的相关性尚不清楚，我的研究小组的结果将深入了解与年龄相关的前庭平衡控制改变相关的潜在因素。 第二个短期目标将通过利用成人自然衰老和疲劳来确定与皮质对站立的贡献相关的机制。 对于年轻人来说，皮质对维持站立平衡的参与是有限的。 然而，皮质对平衡的贡献可能会随着成人自然衰老而增强，但这一概念尚未得到彻底解决。 我的研究小组将利用神经肌肉疲劳和长期适应状态来确定与皮质控制站立平衡相关的机制。 所提出的实验将为皮质和感觉（即前庭）相关机制如何通过利用急剧和长期改变的状态来调节站立平衡控制提供有价值的见解。