Vestibular contribution to the control of human upright stance

项目摘要/摘要 这个项目的长期目标是了解来自内耳平衡的运动信息 前庭系统的传感器有助于控制人类的平衡，并确定 哪种前庭电刺激(GVS)可用于恢复有用的前庭平衡 前庭功能减退的受试者。GVS长期以来一直被用来定性地证明 前庭对平衡控制的贡献，但缺乏详细的量化了解。工程学 将应用系统识别方法和建模来开发GVS，作为一种量化工具 研究前庭对平衡控制的贡献以及作为一种潜在的假体辅助来增强平衡 在有前庭缺陷的受试者中。 拟议的工作有三个具体目标。第一个目标是将实验方法和建模方法结合起来 目的：(1)定义来自前庭传感器的运动信息如何有助于平衡控制，(2)确定如何 前庭方向信息与本体感觉、躯体感觉和视觉信息相结合 系统，(3)确定如何使用组合的感觉信息来产生矫正反应 施加在多节段身体上的外部扰动，以及(4)确定受试者如何与双侧 前庭丢失(BVL)是对前庭丢失的补偿。在第一个目标中开发的模型提供 关于平衡控制机制的量化假说。第二个目标将使用GVS的结果 测试以确定GVS诱发的身体摇摆与预期的摇摆不同于自然激活的 前庭感受器通过实际的头部运动。我们将开发一种方法来解释这些差异，并且 然后使用GVS来测试我们的基于模型的多节段平衡控制假设是否预测 前庭对平衡控制的贡献随着环境和刺激条件的变化而变化。这个 第三个目标将利用GVS的识别特征--诱发的平衡反应和一个基于模型 了解平衡控制系统开发的方法，即利用GVS反馈，基于实时 测量头部运动，以操纵前庭对平衡控制的贡献。因为许多BVL 受试者对GVS仍然敏感，存在实时GVS反馈以恢复功能的潜力 前庭对BVL受试者平衡控制的有用贡献。 拟议实验的成功完成将为前庭贡献提供新的见解 到人类平衡控制和补偿前庭丧失的机制。方法的发展 为了准确地处理前庭运动信息，使用GVS反馈将有助于未来 前庭对运动任务的贡献和可能对发育有潜在贡献的研究 前庭假体。

Project Summary/Abstract The long-term goals of this project are to understand how motion information from the inner-ear balance sensors of the vestibular system contributes to the control of balance in humans and to determine the extent to which galvanic vestibular stimulation (GVS) can be used to restore a useful vestibular contribution to balance in subjects with diminished vestibular function. GVS has long been used to demonstrate qualitatively a vestibular contribution to balance control, but a detailed quantitative understanding is lacking. Engineering system-identification methods and modeling will be applied to develop GVS as a quantitative tool for investigating the vestibular contribution to balance control and as a potential prosthetic aid to enhance balance in subjects with vestibular deficits. The proposed work has three specific aims. The first aim will combine experimental and modeling methods to: (1) define how motion information from vestibular sensors contributes to balance control, (2) determine how vestibular orientation information is combined with information from proprioceptive, somatosensory, and visual systems, (3) determine how combined sensory information is used to generate corrective responses to external perturbations imposed on a multi-segmental body, and (4) identify how subjects with bilateral vestibular loss (BVL) compensate for their vestibular loss. Models developed in the first aim provide quantitative hypotheses about mechanisms controlling balance. The second aim will use results from GVS tests to identify aspects of GVS-evoked body sway that differ from sway expected from the natural activation of vestibular receptors by actual head motion. We will develop a method that accounts for these differences, and then use GVS to test whether our model-based hypotheses of multi-segmental balance control predict how the vestibular contribution to balance control changes as a function of environmental and stimulus conditions. The third aim will use the identified characteristics of GVS-evoked balance responses and a model-based understanding of the balance control system to develop a method that uses GVS feedback, based on real-time measures of head motion, to manipulate the vestibular contribution to balance control. Because many BVL subjects remain sensitive to GVS, the potential exists for real-time GVS feedback to restore a functionally useful vestibular contribution to balance control in BVL subjects. Successful completion of the proposed experiments will provide new insights into the vestibular contribution to human balance control and mechanisms that compensate for vestibular loss. The development of methods for accurately manipulating vestibular-motion information using GVS feedback will facilitate future investigations of the vestibular contribution to motor tasks and could potentially contribute to the development of a vestibular prosthesis.