Physiological and biomechanical analysis of muscle synergies in rat locomotion

描述(申请人提供)：运动是神经和肌肉骨骼系统之间复杂相互作用的结果。无论是研究健康受试者的运动控制还是损伤后的运动控制，都必须考虑这两个系统，以便解释运动的功能或功能障碍。我们的长期研究目标是调查这种相互作用，为健康和疾病中潜在的生物运动控制的机制和策略提供见解。在这里提出的研究中，我们将检查大鼠的运动产生，检查它的神经控制和生物力学。尽管大鼠越来越多地被用来研究运动控制和损伤的后果，但它的许多行为和生物力学特征尚不清楚。我们将评估关于生物运动控制的一个具体假设：运动系统通过少量肌肉群的灵活组合或肌肉协同作用来产生运动。我们认为，每个这样的组中的肌肉不是任意的，而是适应运动系统的生物力学。我们的具体目标是1)使用新的计算分析，评估自由行为大鼠在运动过程中记录的肌肉激活模式是否可以很好地描述为肌肉协同效应的组合；2)建立大鼠后肢肌肉骨骼系统的生物力学模型，用于解释已识别的肌肉协同效应；3)使用该模型来检测已识别的协同效应的生物力学行为，并评估是否可以通过肌肉协同效应的组合产生复杂的行为。因此，这里提出的研究有两个同时的目的，都与公共卫生有潜在的相关性。首先，通过测试哺乳动物产生复杂运动的这一特定假设，这项研究将为包括人类在内的其他哺乳动物的运动控制提供见解。第二，通过为分析大鼠运动控制提供基本信息和强大的计算工具，本研究将极大地增加我们对这一重要模型系统的基本理解。基于这种理解，我们可以更好地评估损伤在这个系统中的影响，并可以更容易地制定康复和再生的策略，这些策略随后可能会转化为临床环境。

DESCRIPTION (provided by applicant): Movement results from the complex interplay between neural and musculoskeletal systems. Whether investigating motor control in healthy subjects or following injury, both systems must be considered in order to interpret the function, or dysfunction, of movement. Our long term research goal is to investigate this interplay, providing insights into the mechanisms and strategies underlying biological motor control in health and disease. In the research proposed here, we will examine the production of locomotion in the rat, examining both its neural control and its biomechanics. Although the rat is being used increasingly to study motor control and the consequences of injury, many features of its behavior and biomechanics are unknown. We will evaluate a specific hypothesis about biological motor control: that motor systems produce movement through the flexible combination of a small number of muscle groups, or muscle synergies. We propose that the muscles within each such group are not arbitrary but are adapted to the biomechanics of the motor system. Our specific aims are to 1) Evaluate, using novel computational analyses, whether the patterns of muscle activations recorded during locomotion in freely behaving rats can be well described as the combination of muscle synergies; 2) Develop a biomechanical model of the hindlimb musculoskeletal system of the rat to be used in interpreting the identified muscle synergies; 3) Use this model to examine the biomechanical actions of identified synergies and to assess whether complex behaviors can be produced by combination of muscle synergies. The research proposed here thus serves two simultaneous purposes, both of potential relevance to public health. First, by testing this specific hypothesis of the production of complex movement by a mammal, this research will provide insights to motor control in other mammals, including humans. Second, by providing basic information and powerful computational tools for the analysis of motor control in the rat, this research will greatly increase our basic understanding of this important model system. Based on this understanding, we can better evaluate the effects of injury in this system and can more readily develop strategies of rehabilitation and regeneration, strategies which might then be translated into clinical settings.