ACTIVITY DEPENDENT PLASTICITY AFTER HUMAN SPINAL CORD INJURY

人类脊髓损伤（SCI）后行走的恢复前景在严重损伤后是暗淡的。恢复的预后主要基于可检测的随意腿功能，这指导了SCI后行走的康复策略。这种方法是基于假设从传统的层次模型的神经控制的运动在人类指定的大脑作为主要的控制器和脊髓作为管道的脊髓上的信号和反射通路。我们实验室和其他实验室的最新结果表明，运动的神经控制的综合模型，分配脊髓作为一个重要的运动神经控制器，整合感觉和脊髓上的信号，以产生有效的运动输出。在这个建议中，我们通过理解感官和 在每次任务特定训练之前和之后，在步进和站立的运动任务期间，人脊髓的脊髓上信号处理。我们从理论上说，人类脊髓的神经回路的功能组织产生一个特定的传出模式时，提出了一套预期的运动和动力模式。我们假设，这neuralcircuitry可以适应一组特定的运动和动力学模式的重复演示，以可预测的方式调制传出输出。我们进一步假设，不完全SCI后，脊髓上和感觉信号都可以被人类脊髓整合，产生与重复站立或踏步训练相关的特定运动输出。我们 将研究临床完全SCI后的个体，以了解人类脊髓在处理感觉信号中的作用。我们将研究临床上不完全性脊髓损伤的个体，以评估在重复站立或踏步训练后，棘上和感觉信号产生功能输出的整合潜力。我们将检查这些SCI受试者在双侧和单侧踏步期间以及在重复踏步或站立训练后在跑步机上使用体重支撑的功能任务期间的下肢肌电活动、运动学和动力学。这些研究将证明在PPG动物模型中研究的使用依赖性可塑性方面。识别在踏步过程中促进运动输出的特定感觉线索;并评估重复任务特定训练是否可以诱导 导致脊髓损伤后功能改善的脊髓和脊髓上中心的活动依赖性可塑性将对神经损伤后行走恢复的新康复策略具有重要意义。此外，优化功能恢复的训练策略与不断涌现的有前途的神经再生方法相结合也将非常重要。

The prospects for recovery of walking after human spinal cord injury (SCI) are dismal after a severe injury. The prognosis for recovery is primarily based on detectable voluntary leg function and this directs the rehabilitative strategy for walking after SCI. This approach is based on assumptions from the conventional hierarchal model of the neural control of locomotion in humans that designates the brain as the primary controller and the spinal cord as a conduit for supraspinal signals and reflex pathways. Recent results from our laboratory and others suggest an integrative model of the neural control of locomotion, allocating the spinal cord as an important neural controller of locomotion that integrates sensory and supraspinal signals to generate effective locomotor output. In this proposal we test this model by understanding sensory and supraspinal signal processing by the human spinal cord during the motor tasks of stepping and standing before and after each task specific training. We theorize that the neural circuitry of the human spinal cord is functionally organized to generate a particular efferent pattern when an expected set of kinematic and kinetic patterns are presented. We hypothesize that this neuralcircuitry can adapt to the repetitive presentation of a specific set of kinematic and kinetic patterns to modulate the efferent output in a predictable manner. We further hypothesize that after incomplete SCI both supraspinal and sensory signals can be integrated by the human spinal cord to generate a specific motor output that is related to repetitive stand or step training. We will study individuals following clinically complete SCI to understand the role of the human spinal cord in processing sensory signals. We will study individuals with clinically incomplete SCI to assess the integrative potential of supraspinal and sensory signals to generate functional output after repetitive stand or step training. We will examine the electromyographic activity, kinematics and kinetics of the lower limbs of these SCI subjects during bilateral and unilateral stepping and during functional tasks using body weight support on a treadmill after repetitive step or stand training. These studies will demonstrate aspects of use-dependent plasticity that are being studied in the animal models of this PPG. Identifying the specific sensory cues that facilitate motor output during stepping; and assessing whether repetitive task specific training can induce activity-dependent plasticity of spinal and supraspinal centers to result in functional improvements after spinal cord injury will have significant implications for new rehabilitative strategies for the recovery of walking after neurologic injury. Further, optimizing training strategies for functional recovery will also be extremely important in combination with promising neural regeneration approaches that are continuously emerging.