HEAD CONTROL MECHANISMS DURING VOLUNTARY TRUNK MOVEMENTS

躯干自愿运动期间的头部控制机制

• 批准号: 6363930
• 负责人: Timothy C Hain
• 金额: $ 14.06万
• 依托单位: NORTHWESTERN UNIVERSITY AT CHICAGO
• 依托单位国家: 美国
• 财政年份: 1999
• 资助国家: 美国
• 起止时间: 1999-03-01 至 2003-02-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6363930
• 关键词: balance; brain disorders; clinical research; computer simulation; electromyography; functional ability; head movements; human subject; neck; neuromuscular function; proprioception /kinesthesia; psychomotor function; sensorimotor system; vestibular pathway; vestibuloocular reflex

The aim of this project is to determine how intentional mechanisms contribute to head stabilization in the pitch (sagittal) plane during voluntary trunk movements in persons with intact and bilaterally impaired vestibular (BVL) systems. One set of studies will quantify the contributions made by intentional mechanisms beyond reflex and mechanical processes. A second set of studies will evaluate what subtypes of intentional strategies are used to stabilize the head under different conditions. Empirical and computer modeling approaches will test the hypotheses that intentional mechanisms contribute significantly to head stabilization in the BVL as well as intact subject, and that these groups use different subtypes of strategies to stabilize their heads. In the empirical studies, subjects will sit on a sled that can translate in the anterior-posterior direction. They will voluntarily control translation of the sled by a hand-held joystick, and have some sled motions imposed on them. The sled translations generate forces that destabilize the head in the pitch plane. Analyses of head motion and torques and of electromyographic activity in the neck and trunk muscles will reveal how well subjects counteract the head-destabilizing forces during sled translation. The data also will reveal whether subjects stabilize their heads by avoiding the disturbance (reducing trunk subjects motion), anticipating and predictively cancelling the disturbance, by stiffening their neck through muscle cocontraction, or by relying on reflexes and passive mechanics. An analytical model of the head-neck control system will be used to run simulations that will determine how much intentional mechanisms contribute to head stabilization, and that will establish how combinations of intentional, mechanical and reflex strategies could work together to stabilize the head. This project is the first to evaluate intentional head-stabilizing mechanisms during voluntary trunk movements. The project also will add to basic knowledge of head control mechanisms by evaluating intentional processes during voluntary movements that are similar to activities of daily life, which generally involve voluntary rather than imposed motion of the trunk. The comparison of intact and BVL populations will elucidate why some persons with BVL recover relatively high functional levels, and others do not.

这个项目的目的是确定如何故意机制 有助于头部在俯仰（矢状）平面中的稳定， 完整的和双侧的人的自主躯干运动 前庭系统受损。 一组研究将量化 反射以外的有意机制的贡献， 机械过程。 第二组研究将评估 有意策略的子类型用于稳定头部， 不同条件 经验和计算机建模方法将 测试假设，故意机制有助于显着 BVL中的头部稳定以及完整受试者，并且 这些群体使用不同的策略亚型来稳定他们的 构造标准部件. 在实证研究中，受试者将坐在雪橇上， 在前后方向上平移。 他们会自愿 通过手持式操纵杆控制雪橇的平移，并有一些 雪橇运动强加在他们身上。 滑板平移产生力 使头部在俯仰平面内不稳定。 头部运动分析 以及颈部和躯干的肌电活动 肌肉将揭示受试者如何抵消头部不稳定 雪橇平移期间的力。 数据还将揭示， 受试者通过避免干扰来稳定他们的头部（减少 躯干受试者运动），预测和预测性地取消 障碍，通过肌肉共同收缩使颈部僵硬，或 依靠反射和被动力学。 的分析模型 头颈控制系统将用于运行模拟， 确定有意识的机制在多大程度上有助于头部 稳定，这将建立如何结合故意， 机械和反射策略可以共同作用来稳定 头 这个项目是第一个评估故意头部稳定 在自主躯干运动的机制。 该项目还将增加 通过评估故意的头部控制机制的基本知识 在自愿运动过程中，类似于 日常生活，通常涉及自愿而不是强加的运动 的树干。 完整和BVL群体的比较将 阐明为什么一些BVL患者恢复相对较高的功能 水平，而其他人则没有。