Limb coordination during locomotion before and after spinal cord injury

项目摘要 协调肢体运动的能力是哺乳动物运动的主要特征之一。肢体间 在复杂和/或不断变化的环境中导航时，协调对于保持平衡至关重要。它涉及到 神经系统不同层次神经回路与生物力学的复杂动态相互作用 肌肉骨骼系统的特性，使动物能够调整运动速度和步态，以适应目标导向的行为。 神经系统内的相互作用包括控制每一条肢体的脊髓回路之间的相互作用、脊髓上的输入 以及来自四肢的感觉反馈。脊髓损伤(SCI)等疾病引起的神经系统疾病 扰乱人类和动物模型的肢体协调，从而损害运动。尽管它们显然很重要，但 控制肢体间协调和促进脊髓损伤及其他损伤后运动恢复的机制 人们对神经系统疾病仍知之甚少。 为了解决这一知识差距，我们将整合多种实验和建模方法来研究 脊髓损伤前后猫模型肢体间协调控制的神经和生物力学机制 大脑和脊髓之间和/或控制前肢和后肢的回路之间的神经通讯 动静。该项目将在三个调查组之间的密切互动合作中进行， 在猫运动实验研究方面具有很强的互补性专业知识，包括脊髓损伤模型(Alain Frigon， 雪布鲁克大学)，猫运动的生物力学(鲍里斯·普里卢茨基，佐治亚理工学院)和神经控制 运动(伊利亚·雷巴克，德雷克塞尔大学)。 该项目有以下具体目标：(1)表征完整和 脊椎猫在规则跑步机和分裂带跑步机上的运动；(2)扩展和改进了现有的计算模型 神经回路和脊髓中枢模式发生器参与运动控制；(3)开发一种集成的 猫运动的四足神经力学模型建立完整的猫四足神经力学模型 (4)研究运动时肢体协调的神经和生物力学控制。 相互关联、互为补充的实验和建模研究。 这些研究的结果将对我们理解肢体是如何 在运动过程中是协调的，以及这种协调在脊柱通路中断后是如何改变和调整的 在左-右或颈-腰环路之间。研究结果将确定神经通路和生物力学机制。 这可能是有针对性的，以改善患有各种运动障碍的人的肢体间协调，如脊髓损伤，中风， 和帕金森氏症。

Project Summary The ability to coordinate movements of the limbs is one of the main features of locomotion in mammals. Interlimb coordination is essential for maintaining balance when navigating in complex and/or changing environments. It involves complex dynamic interactions between neural circuits at different levels of the nervous system and biomechanical properties of the musculoskeletal system to allow animals to adjust locomotor speed and gait for goal-oriented behaviors. Interactions within the nervous system include those between the spinal circuits controlling each limb, supraspinal inputs and sensory feedback from the limbs. Neurological disorders resulting from spinal cord injury (SCI) and other diseases disrupt limb coordination in humans and animal models, thus impairing locomotion. Despite their obvious importance, the mechanisms that control interlimb coordination and contribute to locomotor recovery following SCI and other neurological disorders remain poorly understood. To address this gap in knowledge, we will integrate multiple experimental and modeling approaches to investigate the neural and biomechanical mechanisms controlling interlimb coordination in a feline model before and after SCI disrupting neural communication between the brain and spinal cord and/or between the circuits controlling fore- and hindlimb movements. The project will be performed in close interactive collaboration between three groups of investigators with strong and complementary expertise in the experimental study of cat locomotion, including SCI models (Alain Frigon, Université de Sherbrooke), biomechanics of cat locomotion (Boris Prilutsky, Georgia Tech) and neural control of locomotion (Ilya Rybak, Drexel University). The project has the following Specific Aims: (1) Characterize muscle synergies and limb kinematics in intact and spinal cats during locomotion on regular and split-belt treadmills; (2) Extend and refine the current computational model of neural circuits and spinal central pattern generators involved in the control of locomotion; (3) Develop an integrated quadrupedal neuromechanical model of cat locomotion Develop an integrated quadrupedal neuromechanical model of cat locomotion; (4) Investigate the neural and biomechanical control of interlimb coordination during locomotion using interrelated and complementary experimental and modeling studies. Results obtained from these studies will have an important theoretical impact on our understanding of how the limbs are coordinated during locomotion and how this coordination is altered and adjusted after disruption of spinal pathways between left-right or cervical-lumbar circuits. The results will identify neural pathways and biomechanical mechanisms that could be targeted to improve interlimb coordination in people with various movement disorders, such as SCI, stroke, and Parkinson's disease.