Mechanisms underlying impaired postural corrections following stroke

中风后姿势矫正受损的机制

基本信息

批准号：
9269590
负责人：
CLAIRE F. HONEYCUTT
金额：
$ 24.46万
依托单位：
ARIZONA STATE UNIVERSITY-TEMPE CAMPUS
依托单位国家：
美国
项目类别：
财政年份：
2015
资助国家：
美国
起止时间：
2015-02-05 至 2019-01-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/9269590
关键词：
Address Agonist Automobile Driving Bilateral Caring Complex Data Development Effectiveness Elderly Electromyography Equilibrium Fall prevention Family Flexor Future Goals Hospitals Impairment Incidence Individual Involuntary Movements Knowledge Lead Limb structure Link Measures Mediating Motor Movement Muscle Outcome Study Paresis Patients Pattern Performance Persons Population Posture Prevention program Public Health Quality of life Recovery Reflex action Rehabilitation therapy Reporting Risk Factors Role Shapes Stereotyping Stimulus Stroke Surface Time Toes Training Training Programs Translations United States Weight Work arm arm movement base cost effective therapy exercise intervention fall risk falls improved individualized medicine kinematics limb movement medical complication motor impairment post stroke programs relating to nervous system response stroke survivor treadmill

项目摘要

PROJECT ABSTRACT/SUMMARY Fall prevention programs have had mixed results highlighting the need for more effective therapies that tackle the most common medical complication in stroke survivors. Task-specific training, which directly targets improving an individual's response during a fall, offers potential. The long-term goal of this proposal is to develop task-specific training that accounts for the unique balance challenges of stroke survivors that is both effective and time efficient. The ability to implement a task-specific training program in stroke survivors is thwarted by a lack of empirical evidence about which factors and mechanisms lead to a failed recovery during a balance disturbance in this population. An essential component of a successful recovery (avoidance of a fall) is compensatory limb movement – taking a step to regain balance or reaching to a stable surface. We recently noted important similarities between compensatory movements and startle-evoked movements – the involuntary release of planned movement when exposed to startling stimuli. Specifically, startle-evoked and compensatory movements share similar deficits following stroke – delayed, diminished muscle activity, and inappropriate patterns of muscle activation. Thus our central hypothesis is that deficits in compensatory movements post-stroke are driven by deficits in startle-evoked movements. In Aim 1, our objective is to quantify stroke survivors' response during a balance disturbance identifying the key, trainable factors that lead to unsuccessful recovery (i.e. a fall). In brief, stroke survivors will be exposed to backward translations of a treadmill while quantifying stability measures, trunk and step kinematics, paretic limb parameters, and electromyography. Factors will be assessed for their ability to classify successful (fall avoidance) and failed (fall) recoveries. These factors can then be assessed for trainability in future task-specific training paradigms for stroke survivors. In Aim 2, we will pursue identification of the mechanism driving deficits in compensatory movements to arm perturbation in stroke survivors. Our objective is to evaluate the impact of deficits in startle- evoked movement on the ability of stroke survivors to effectively compensate during an arm perturbation. To precisely control perturbation parameters and allow bilateral assessment of paretic and non-paretic limbs, we will evaluate subjects while seated. In Aim 3, we will combine knowledge gained in Aims 1 & 2 and evaluate the link between factors that contribute to falls and the mechanisms proposed. Our objectives are to 1) evaluate the link between triggering a startle-evoked movement and successful compensatory movement during a balance challenge in unimpaired individuals and 2) evaluate the relationship between deficits in startle-evoked movement and deficits in compensatory limb movements post-stroke. The rationale for the proposal is to establish both the factors and mechanisms driving unsuccessful recovery during a fall post- stroke in order to generate an effective task-specific training paradigm in the next application.

项目摘要/总结跌倒预防计划的结果好坏参半，突出表明需要更有效的治疗方法来解决中风幸存者最常见的医疗并发症，直接针对特定任务的训练。该提案的长期目标是改善个人在跌倒期间的反应。制定针对中风幸存者独特的平衡挑战的特定任务培训对中风幸存者实施特定任务培训计划的能力是有效且省时的。由于缺乏关于哪些因素和机制导致经济复苏失败的经验证据，该人群的平衡障碍是成功康复的重要组成部分（避免跌倒）。是补偿性肢体运动——采取措施恢复平衡或到达稳定的表面。代偿性运动和惊吓诱发运动之间有重要的相似之处—— 当受到惊吓刺激时，会不自觉地释放出计划好的动作。中风后代偿运动也有类似的缺陷——肌肉活动延迟、减少，因此，我们的中心假设是代偿性缺陷。中风后的运动是由惊吓诱发运动的缺陷驱动的。在目标 1 中，我们的目标是：中风定量幸存者在平衡障碍期间的反应，确定导致中风的关键的、可训练的因素简而言之，中风幸存者将面临向后翻译。跑步机，同时量化稳定性指标、躯干和脚步运动学、瘫痪肢体参数，以及将评估因素对成功（避免跌倒）和失败进行分类的能力。然后可以评估这些因素在未来特定任务训练范例中的可训练性。对于中风幸存者，我们将寻求确定导致补偿性缺陷的机制。我们的目标是评估惊吓幸存者的运动对手臂扰动的影响。诱发运动对中风幸存者在手臂扰动期间有效补偿的能力的影响。精确控制扰动参数并允许对瘫痪和非瘫痪肢体进行双边评估，我们在目标 3 中，我们将结合目标 1 和 2 中获得的知识并评估。导致跌倒的因素与提出的机制之间的联系是：1) 评估触发惊吓诱发运动和成功代偿运动之间的联系在对未受损个体进行平衡挑战期间，2）评估缺陷之间的关系惊吓诱发的运动和中风后肢体代偿运动的缺陷。建议建立导致跌倒后恢复不成功的因素和机制。中风以便在下一步应用中生成有效的特定任务训练范例。