Stretch Reflex Contributions to Multijoint Coordination

牵张反射对多关节协调的贡献

• 批准号: 8535216
• 负责人: ERIC JON PERREAULT
• 金额: $ 29.47万
• 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: 2006
• 资助国家: 美国
• 起止时间: 2006-09-01 至 2016-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8535216
• 关键词: Adaptive Behaviors; Address; Affect; Age; Behavior; Behavioral; Brain Injuries; Brain Stem; Cerebral Palsy; Consensus; Corticospinal Tracts; Data; Diffusion Magnetic Resonance Imaging; Disease; Eating; Freedom; Functional disorder; Funding; Goals; Hand; Human; Impairment; Individual; Lead; Lesion; Link; Literature; Mediating; Modification; Motor; Movement; Muscle; Neural Pathways; Parkinson Disease; Pathway interactions; Pattern; Performance; Population; Posture; Protocols documentation; Public Health; Reaction; Reflex action; Reflex control; Regulation; Rehabilitation therapy; Relative (related person); Research; Robot; Robotics; Role; Speed; Spinal cord injury; Stroke; Structure; Survivors; System; Testing; Therapeutic Intervention; Time; Training; Uncertainty; Work; arm; base; disability; haptics; hemiparesis; motor impairment; nervous system disorder; neuromechanism; novel strategies; post stroke; relating to nervous system; research study; response; spinal reflex; stretch reflex

DESCRIPTION (provided by applicant): There is a fundamental gap in our understanding of how long-latency stretch reflexes (LLSRs) contribute to the control of multijoint posture and movement in the human arm. This is an important problem because many neurological disorders impair stretch reflexes, resulting in well-documented motor dysfunction. Attempts to enhance motor function through a modification of reflex behavior have been largely equivocal, however, due at least in part to the unknown relationships between specific reflex subtypes and motor abilities. Our central theme is that much of the gap can be filled by considering the pathways that contribute to LLSRs and their specific, context-dependent contributions to motor function. LLSRs contain at least two key behavioral compo- nents: "stabilizing reflexes", contributing to posture regulation, and "triggered reactions" for the rapid release of planned actions. We have shown that these behaviors are mediated by separate pathways and that their relative importance depends on the task performed. Our recent work focused on the stabilizing component of the LLSR. Here we propose to investigate triggered reactions. Our central hypothesis is that triggered reactions can act independently from stabilizing reflexes, based on our preliminary data demonstrating that stabilizing LLSRs are lost following stroke but that triggered reactions are spared. Importantly, our data also suggest that appropriately triggered reactions increase speed and coordination in stroke subjects, potentially forming the basis for effective rehabilitation. First, however, we must clarify the LLSR role in controlling unimpaired posture and movement, and its integrity and function following stroke. Our Specific Aims are: 1) to determine if stabilizing reflexes and triggered reactions are controlled independently; 2) to determine how uncertainty affects the planning, execution and efficacy of triggered reactions; and 3) to determine how brain injury due to stroke im- pairs stabilizing stretch reflexes and triggered reactions. The first two aims focus on the behavioral relevance of triggered reactions, and will be completed in unimpaired subjects using a 3D robotic manipulator to charac- terize LLSRs during the key transition from maintaining arm posture to initiating a reach. Our third aim will be completed in stroke subjects and age-matched controls. It parallels the first two aims, but also will use diffusion tensor imaging (DTI) to quantify lesions in the descending pathways thought to regulate the stabilizing and triggered components of the LLSR. The contributions of this research will be a clear description of the role of triggered reactions in the control of movement, how that role is integrated with posture-stabilizing components of the LLSR, and how the LLSR is impaired following stroke in relation to the neural pathways contributing to it. With this refined understanding, we hope to lay the groundwork for using triggered reactions in rehabilitation training paradigms aimed at enhancing the ability to voluntarily initiate appropriate motor patterns at appropri- ate latencies in stroke survivors.

描述（由申请人提供）：我们对长期长期伸展反射（LLSR）的理解存在根本差距，这有助于控制人类手臂中的多焦点姿势和运动。这是一个重要的问题，因为许多神经系统疾病会损害伸展反射，从而导致有据可查的运动功能障碍。尝试通过反射行为来增强运动功能的尝试在很大程度上是模棱两可的，但是至少部分是由于特定反射亚型和运动能力之间未知的关系。我们的中心主题是，可以考虑有助于LLSR及其对运动功能的特定，上下文依赖的贡献的途径来填补许多差距。 LLSR至少包含两个关键的行为组成部分：“稳定反射”，有助于姿势调节，以及“触发反应”，以快速释放计划的动作。我们已经表明，这些行为是由单独的途径介导的，它们的相对重要性取决于执行的任务。我们最近的工作集中于LLSR的稳定成分。在这里，我们建议研究触发的反应。我们的中心假设是，基于我们的初步数据，触发的反应可以独立于稳定反射行动，表明稳定LLSR在中风后丢失，但触发的反应幸免。重要的是，我们的数据还表明，适当触发的反应会增加中风受试者的速度和协调，这可能构成了有效康复的基础。但是，首先，我们必须阐明LLSR在控制未损坏的姿势和运动中的作用，以及中风后其完整性和功能。我们的具体目的是：1）确定是否独立控制稳定反射和触发反应； 2）确定不确定性如何影响触发反应的计划，执行和功效； 3）确定中风造成的脑损伤是如何稳定拉伸反射和触发反应的。前两个目的侧重于触发反应的行为相关性，并将使用3D机器人操纵器在不受障碍的受试者中完成，以使LLSR在从保持手臂姿势到启动到达的关键过渡过程中表征LLSR。我们的第三个目标将在中风主题和年龄匹配的控件中完成。它与前两个目标相似，但也将使用扩散张量成像（DTI）来量化被认为调节LLSR的稳定和触发成分的下降途径中的病变。这项研究的贡献将清楚地描述了触发反应在控制运动中的作用，该作用如何与LLSR的姿势稳定成分集成在一起，以及在中风后与神经途径相关后，LLSR如何受损。有了这种精致的理解，我们希望为在康复训练范式中使用触发的反应奠定基础，旨在增强在中风幸存者中自愿启动适当的运动潜伏期的适当运动模式的能力。