Central and peripheral mechanisms controlling human balance control

我的五年研究计划的短期目标是了解平衡控制和涉及平衡相关感官信息的检测、整合和感知的潜在神经机制如何受到威胁和相关因素的影响，如焦虑、恐惧和觉醒。这项研究是我长期研究目标的一部分，目的是发现中枢和周围神经系统如何促进人类的平衡控制。人们很容易理解威胁是如何影响平衡的，如果你考虑一下当一个人试图在不同高度的平衡木上行走时会发生什么。当横梁在地面上时，表现通常是成功的，但当横梁升高时，大多数人往往会失去平衡而摔倒。类似的因素可能导致那些害怕摔倒的人出现平衡问题和摔倒，也可能影响那些在威胁或压力条件下工作的人的表现和安全。我们的研究表明，在其他方面健康的个体中，威胁的增加会直接影响他们控制平衡的方式。然而，威胁是如何影响大脑调节平衡以适应不断变化的感觉条件和为平衡障碍做准备的能力的，具体方式目前尚不清楚。同样，对于在威胁条件下如何检测、整合和有意识地感知这些变化的感官信息，我们也知之甚少。该程序旨在检查不同的威胁来源如何影响：a)如何整合和重新加权感觉信息以在安静的姿势中保持平衡，b)如何在预期的姿势干扰之前准备保护性姿势反应，c)如何从肌肉和皮肤中的受体接收与平衡相关的感觉信息的敏感性被调节，以及d)如何改变与平衡相关的感觉信息的有意识感知。该研究项目将提供重要的基础知识，用于设计诊断和治疗平衡障碍和跌倒的新方法，并改善必须在恐惧、焦虑和/或压力相关的唤醒条件下生活、工作或表演的个人的训练、表现和安全。

The short term goal of my five year research program is to understand how balance control and the underlying neural mechanisms involved in the detection, integration and perception of balance-relevant sensory information are influenced by threat and associated factors, such as anxiety, fear and arousal. This research is part of my long term research goal to discover how the central and peripheral nervous systems contribute to human balance control. One can easily appreciate how threat can influence balance, if you consider what happens when someone tries to walk across a balance beam at different heights. When the beam is on the ground, performance is usually successful, but when the beam is elevated, most people tend to lose their balance and fall. Similar factors may contribute to balance problems and falls in those with a fear of falling, and may also impact performance and safety of those who work under threatening or stressful conditions. Our research has shown that increased threat in otherwise healthy individuals can directly influence the way they control balance. However, the specific way in which threat influences the brain's ability to adjust balance to changing sensory conditions and prepare for balance disturbances is currently unknown. Likewise, there is little knowledge about how this changing sensory information is detected, integrated together and consciously perceived under threatening conditions. The program is designed to examine how different sources of threat influences: a) how sensory information is integrated and re-weighted to maintain balance during quiet stance, b) how protective postural responses are prepared in advance of an expected postural disturbance, c) how the sensitivity of balance-relevant sensory information received from receptors in the muscle, and skin is modulated and d) how the conscious perception of balance-relevant sensory information is changed. The research program will provide important fundamental knowledge needed to design new approaches for the diagnosis and treatment of balance disorders and falls and to improve training, performance and safety of individuals who must live, work or perform under conditions of fear, anxiety and/or stress-related arousal.