EFFECTS OF MOVEMENT CONTEXT ON HEMIPARETIC GRASPING EARLY AFTER STROKE

功能抓握功能的恢复对卒中后偏瘫患者大有裨益。虽然针对任务的训练可能是促进功能恢复的最佳方式，但实施这种抓取训练是困难的，因为有大量的抓取任务乘以大量需要执行这些任务的环境。该项目的长期目标是开发个性化的、以数据为导向的解决方案，以解决如何练习抓握的两难境地，即在什么情况下以及何时练习，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。我们认为，特定的运动环境可能会改善中风后偏瘫患者的握力控制和表现。这一断言的动机是在神经学完好的成年人中的发现表明，运动环境是一个强大的工具，通过引发对同一运动的不同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在时空上为受影响的手部肌肉提供适当的促进，从而提高中风患者的抓握能力。在具体目标1中，我们将通过检验以下假设来确定嵌套在其他动作中的偏瘫抓取是否会得到改善：a)当抓握与伸展相结合时，抓取过程中的手形将得到改善；b)当抓握与升力相结合时，抓取过程中的力产生将得到改善；c)当双手同时抓握时，手形和力产生将得到改善；以及d)上述对抓取的影响将是相加的。以上动作情境的效果将针对用于大多数功能任务的两种类型的抓取进行评估，即掌侧抓取和三指精确抓取。运动学和运动学数据都将被收集和分析，因为功能抓取依赖于准确的手形和协调的作用力产生。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，以改善中风后的抓握能力。我们的结果将在临床实践中特别突出，因为它们将来自提供大部分中风康复服务的同一时间段。在康复过程中，在特定的运动环境中练习握力可能会导致更成功的表现，导致上肢功能的更大程度恢复。康复期间更成功的表现也可能导致在康复之外进行更多的练习和使用。

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.