EFFECTS OF MOVEMENT CONTEXT ON HEMIPARETIC GRASPING EARLY AFTER STROKE

功能抓握的恢复对脑卒中后偏瘫患者有很大的益处。虽然特定任务的训练可能是促进功能恢复的最佳方式，但实施这种抓握训练是困难的，因为有大量的抓握任务乘以需要执行这些任务的大量上下文。该项目的长期目标是开发个性化的、数据驱动的解决方案，以解决如何练习抓握的困境，即在哪些环境和何时，以改善中风后偏瘫患者的上肢功能。在目前康复服务有限的环境下，迫切需要解决这一困境。我们提出特定的运动环境可能会改善中风后偏瘫患者的抓握控制和表现。这一论断的动机是在神经系统完整的成年人中发现，运动情境是一个强大的工具，可以通过对同一运动引发不同的计划和执行策略来挑战中枢神经系统。这些区域的参与或集中激活可以为受影响的手部肌肉提供时空适当的促进，从而提高中风患者的抓握能力。在具体目标1中，我们将通过测试以下假设来确定在其他动作中嵌套偏滑抓取是否会得到改善：a)当抓取与伸手相结合时，抓取过程中的手形会得到改善；b)当抓取与抬起相结合时，抓取过程中的力产生会得到改善；c)双手同时抓取时，手形和力产生会得到改善；d)上述对抓取的影响将是相加的。上述运动情境的影响将评估用于大多数功能性任务的两种类型的抓握，手掌抓握和三指精确抓握。运动学和动力学数据都将被收集和分析，因为功能性抓取依赖于准确的手形和0 - n协调力的产生。拟议研究的结果将使临床医生能够实施个性化的康复干预措施，以改善中风后的抓取能力。我们的研究结果对临床实践尤其重要，因为它们来自大多数中风康复服务提供的同一时期。在康复过程中，在确定的运动环境中进行抓握练习可能会导致更成功的表现，从而使上肢功能得到更大的恢复。在康复期间更成功的表现也可能导致更多的练习和使用以外的康复。

Restoration of functional grasping would be of great benefit to people with hemiparesis post stroke. While task-specific training may be the best way to promote functional recovery, implementing such training for grasping is difficult because there are an enormous number of grasping tasks multiplied by an enormous number of contexts in which these tasks need to be performed. The long-term goal of this project is to develop individually-tailored, data-driven solutions to the dilemma of how to practice grasping, i.e. in which contexts and when, in order to improve upper extremity function in people with hemiparesis post stroke. Solutions to this dilemma are strongly needed in the current environment of limited rehabilitation services. We propose that specific movement contexts may improve the control and performance of grasping in people with hemiparesis post stroke. This assertion is motivated by findings in neurologically-intact adults suggesting that movement context is a powerful tool to challenge the central nervous system by eliciting different planning and execution strategies for the same movement. Engagement or focused activation from these areas could provide spatiotemporally-appropriate facilitation to affected hand muscles that improves the ability to grasp in people with stroke. In Specific Aim 1, we will determine if hemiparetic grasping is improved when nested within other movements by testing the following hypotheses: a) hand-shaping during grasping will be improved when a grasp is coupled with a reach, b) force production during grasping will be improved when a grasp is coupled with a lift, c) hand-shaping and force production will be improved when both hands grasp simultaneously, and d) the above effects on grasping will be additive. The effects of the above movement contexts will be evaluated for the two types of grasp that are used for most functional tasks, the palmar grasp and the 3-finger precision grasp. Both kinematic and kinetic data will be collected and analyzed because functional grasping depends on accurate hand shaping and 0 n coordinated force productions. Results from the proposed studies will enable clinicians to implement individually-tailored rehabilitation interventions to improve grasping after stroke. Our results will be particularly salient to clinical practice because they will come from the same time period when the majority of stroke rehabilitation services are provided. Practice of grasping in identified movement contexts during rehabilitation may result in more successful performance, leading to greater recovery of upper extremity function. More successful performance during rehabilitation may also lead to more practice and use outside of rehabilitation.