Minimizing Instability with Dynamic Visual Inputs

通过动态视觉输入最大限度地减少不稳定性

• 批准号: 6990535
• 负责人: Emily A Keshner
• 金额: $ 26.12万
• 依托单位: REHABILITATION INSTITUTE OF CHICAGO D/B/A SHIRLEY RYAN ABILITYLAB
• 依托单位国家: 美国
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-01-13 至 2006-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6990535
• 关键词: Minimizing; Instability; Dynamic; Visual; Inputs

DESCRIPTION (provided by applicant): The long-term goal of this project is to understand how balance and gait disorders can be helped by using dynamic visual environments to facilitate sensorimotor relearning during locomotion and stance postural control. When vestibular inputs become unreliable, either from labyrinthine loss or dysfunction, individuals must learn to rely upon visual and proprioceptive pathways to produce appropriate responses for changes in postural orientation or equilibrium. Attempts to produce sensory relearning through practicing postural and purposeful activities in static environments have not proved to be a fully successful intervention, possibly because the controlled inputs do not place the necessary demands on the functionality of the postural system. Individuals may become fixed on one pattern of response and be unable to match the range of disturbances encountered in the environment. We propose to study changes in postural responses and spatial orientation during locomotion within a dynamic visual environment in normal subjects and in patients with bilateral labyrinthine loss. We hypothesize that individuals with vestibular loss become fixed on one strategy of compensation and cannot compensate for the fluctuating demands of a dynamic environment. We will examine whether providing strategies for using visual information assists these individuals in compensating for destabilization. Subjects will be tested during quiet stance and walking on a treadmill while we manipulate the velocity or contextual contrast of a dynamic virtual environment. Segmental excursions and center of pressure will be measured and analyzed with repeated measures ANOVAs to determine if postural organization and orientation is influenced by specific parameters of the peripheral field of view. The parameters that emerge as most destabilizing will be applied in a training program where subjects will be instructed to focus on a distant target or on internal feedback to determine if active performance in a dynamic visual environment increases the response repertoire of individuals with labyrinthine loss. Finally, we will assess whether there is functional carryover from training within a dynamic visual environment. Subjects will perform a simulated physical world task in which they must retrieve and place an object while the world moves around them and obstacles appear in their path. Results from these studies will provide insight into the dynamics of the visualvestibular interaction and identify specific quantitative protocols for therapeutic interventions with balance disorders.

描述（由申请人提供）：该项目的长期目标是了解如何通过使用动态视觉环境促进运动和站立姿势控制过程中的感觉运动重新学习来帮助平衡和步态障碍。当前庭输入因迷路丢失或功能障碍而变得不可靠时，个体必须学会依靠视觉和本体感觉通路对姿势定向或平衡的变化产生适当的反应。通过在静态环境中练习姿势和有目的的活动来进行感觉再学习的尝试尚未被证明是完全成功的干预措施，可能是因为受控输入没有对姿势系统的功能提出必要的要求。个体可能会固定于一种反应模式，而无法匹配环境中遇到的干扰范围。我们建议研究正常受试者和双侧迷路丧失患者在动态视觉环境中运动过程中姿势反应和空间方向的变化。我们假设患有前庭损失的个体会固定于一种补偿策略，并且无法补偿动态环境的波动需求。我们将研究提供使用视觉信息的策略是否有助于这些人补偿不稳定。受试者将在安静的姿势和在跑步机上行走时进行测试，同时我们操纵动态虚拟环境的速度或上下文对比度。将通过重复测量方差分析来测量和分析节段偏移和压力中心，以确定姿势组织和方向是否受到周边视野的特定参数的影响。最不稳定的参数将应用于训练计划，其中受试者将被指示专注于远处的目标或内部反馈，以确定动态视觉环境中的主动表现是否会增加迷宫损失个体的反应能力。最后，我们将评估动态视觉环境中的训练是否有功能遗留。受试者将执行一项模拟的物理世界任务，其中他们必须检索并放置一个物体，同时世界在他们周围移动并且障碍物出现在他们的路径中。这些研究的结果将深入了解视觉前庭相互作用的动态，并确定平衡障碍治疗干预的具体定量方案。