The Human Motor Output Map

人体运动输出图

• 批准号: 9188215
• 负责人: Charles Heckman
• 金额: $ 47.76万
• 依托单位: NORTHWESTERN UNIVERSITY AT CHICAGO
• 依托单位国家: 美国
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-07-01 至 2021-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9188215
• 关键词: Anatomy; Behavior; Brain Stem; Cells; Computer software; Data; Development; Disease; Distal; Electrodes; Goals; Hand; Human; Human body; Intramuscular; Investigation; Isometric Exercise; Joints; Leg; Light; Link; Maps; Measures; Methods; Motor; Motor Neurons; Motor output; Movement; Muscle; Muscle Fibers; Musculoskeletal; Musculoskeletal System; Neuraxis; Norepinephrine; Pattern; Physiological; Play; Population; Positioning Attribute; Process; Protocols documentation; Role; Sensory; Serotonin; Skin; Spinal cord injury; Structure; Surface; Synapses; Torque; Variant; arm; base; design; improved; insight; motor control; muscular structure; neuroregulation; novel; research study; sensory feedback

PROJECT SUMMARY/ABSTRACT All motor output is generated by motoneurons and consequently their firing patterns contain detailed information about the structure of motor commands. Remarkably, this information is accessible in humans, because motoneuron spikes are 1 to 1 with those of their muscle fibers. Our overall concept is that motoneuronal firing patterns vary systematically across the muscles of the human body and that this variation reflects fundamental connections between the synaptic organization of motor commands, the structure of the musculoskeletal system and the diversity of motor tasks. To understand these connections, our overall goal is to create a detailed “motor output map” of the human body, using newly developed array electrodes. The array electrodes are placed on the skin and are capable of measuring the firing patterns of up to 30 motor units simultaneously in the underlying muscle. We plan further technical development of these arrays to expand the range of motor tasks they can be used for. The human motor output map will be created from the analysis of firing patterns of populations of motor units in muscles throughout the body for matched motor tasks. We will interpret the resulting map in light of our recent advances in understanding of how firing patterns of motoneurons are determined by the organization of their synaptic inputs. The effects of excitatory and inhibitory inputs on firing patterns are fundamental for generating firing patterns, but neuromodulatory inputs from the brainstem are equally if not more important. These neuromodulatory inputs release serotonin and norepinephrine, which have a profound influence on the intrinsic excitability of motoneurons and thus control how motoneurons process their excitatory and inhibitory inputs. In Aim 1, we create a basic version of the human motor output map by asking subjects to generate slow linear increases and decreases in torque for more than 20 muscles across the body. The protocol is kept exactly the same across muscles to allow comparisons of the resulting firing patterns. Our primary hypothesis is that muscles involved in stabilization of the body, such as proximal muscles, will generate motor unit firing patterns consistent with high levels of neuromodulatory drive, while muscles involved more in precision tasks will generate patterns consistent with low levels of neuromodulation. These experiments are essentially function anatomy, the proximal-distal variations in firing patterns probably arise from differences in the anatomical projections of synaptic inputs to motor pools. In Aim 2, we assess whether there are task dependent changes in firing patterns, such as increases in neuromodulation drive with increased effort and increases in sensory inhibition with movement. Taken together, these experiments will define the fundamental structure of motor output for the human musculoskeletal structure and provide a quantitative basis for understanding the distortions that occur in disease states like spinal cord injury.

项目摘要/摘要 所有电动机输出均由运动神经元产生，因此其发射方式包含详细的 有关电机命令结构的信息。值得注意的是，在人类中可以访问这些信息， 因为运动神经元的尖峰是1-1，其肌肉纤维的尖峰为1-1。我们的总体概念是 在人体的肌肉中，运动神经元射击模式在系统上有变化，并且这种变化 反映电机命令的突触组织之间的基本联系， 肌肉骨骼系统和运动任务的多样性。要了解这些联系，我们的总体目标是 使用新开发的阵列电极创建人体的详细“电动输出图”。数组 电极放在皮肤上，能够测量最多30个电动机的发射方式 同样在潜在的肌肉中。我们计划进一步的这些阵列的技术开发，以扩展 可以使用的电动机任务范围。人类电动机输出图将根据分析而创建 整个人体肌肉中运动单元种群的射击模式，以进行匹配的运动任务。我们将 根据我们最近了解如何发射模式的进步来解释产生的地图 运动神经元取决于其突触输入的组织。兴奋和 对发射模式的抑制投入是产生点火模式的基础，但是神经调节输入 脑干同样重要。这些神经调节输入释放5-羟色胺和 去甲肾上腺素，对运动神经元的内在刺激有深远的影响，从而控制 运动神经元如何处理其兴奋和抑制投入。在AIM 1中，我们创建了一个基本版本 通过要求受试者产生缓慢的线性增加和扭矩下降来减小的人体发动机输出图 整个身体有20多个肌肉。该协议在整个肌肉中保持完全相同，以允许 比较由此产生的射击模式。我们的主要假设是涉及稳定的肌肉 身体（例如近端肌肉）将产生与高水平的电动机发射模式 神经调节驱动器，而精确任务中更多涉及的肌肉将产生与 神经调节水平较低。这些实验本质上是功能解剖结构，近端是近端 发射模式的变化可能是由于突触输入的解剖学投影而产生的 电动池。在AIM 2中，我们评估是否存在触发模式的任务变化，例如 随着努力的增加和运动抑制的增加，神经调节驱动力的增加。 综上所述，这些实验将定义人类电动机输出的基本结构 肌肉骨骼结构，并为理解发生的扭曲提供了定量基础 疾病状态等脊髓损伤。