Reticulospinal Control of Reaching

网状脊髓的伸展控制

基本信息

批准号：
8629795
负责人：
JOHN A BUFORD
金额：
$ 34.08万
依托单位：
OHIO STATE UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
1999
资助国家：
美国
起止时间：
1999-07-30 至 2016-01-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8629795
关键词：
Affect Area Bilateral Brain Part Brain Stem Cells Cerebral cortex Cervical spinal cord structure Complement Confocal Microscopy Contralateral Data Dorsal Electric Stimulation Exertion Future Investigation Ipsilateral Isometric Exercise Knowledge Label Laboratories Left Light Limb structure Location Measures Monkeys Motor Motor Cortex Movement Neurons Operating System Output Pathway interactions Pattern Physiological Pontine structure Prevalence Recovery Response to stimulus physiology Reticular Formation Side Sorting - Cell Movement Source Spinal Cord Stimulus Stroke Structure Study Subject System Testing Time Tracer Training Upper Extremity Upper limb movement Wheat Germ Agglutinin-Horseradish Peroxidase Conjugate arm awake base cranium improved injured motor control neurophysiology public health relevance relating to nervous system research study stroke recovery stroke rehabilitation theories

项目摘要

DESCRIPTION (provided by applicant): The corticospinal and reticulospinal systems must cooperate for control of reaching and other voluntary movements, but little is known about how this can occur. The studies proposed in this project will use a combined approach of neurophysiology in the awake, behaving monkey and modern neuroanatomical tracing studies to expand knowledge of mechanisms and functions of combined corticospinal and reticulospinal control of upper limb movements. Three cortical motor areas are the subject of the study, the primary motor cortex (M1), the supplementary motor area (SMA), and the dorsal premotor cortex (PMd). M1 and SMA are strong sources of corticospinal projections. PMd is also a source of corticospinal projections, and its activity is well related to whole-arm reaching movements. SMA and PMd are strong sources of corticoreticular projections to the reticulospinal system. The reticulospinal system is studied in the pontomedullary reticular formation (PMRF) of the brainstem. In Aim 1, electrical stimulation of cortical motor areas and the PMRF alone and in concert reveals how outputs from these descending systems combine for control of the ipsilateral and contralateral arm. There is also evidence that the corticospinal system can compete to block output of the reticulospinal system, and this study will reveal how and where that cortical gating of PMRF output occurs. Even at the single neuron level, this project has produced evidence of interactions between corticospinal and reticulospinal neurons, and defining how this relates to control of reaching is the final part of Aim 1. Throughout studies for Aim 1, the subject reaches with both arms, but uses only one arm at a time. Aim 2 employs a different apparatus to require coordinated bimanual exertions. Here, the hypothesis is that reticulospinal neurons will have activity patterns that best match the most common result of electrical stimulation in the PMRF, a double reciprocal pattern between the limbs with ipsilateral flexion and contralateral extension. Additional electrical stimulation studies for Aim 2 will also determine how cortical gating of PMRF output differs when the pattern of bilateral arm exertions matches or departs from the movements produced by the typical PMRF output synergies. Aim 3 employs complementary neuroanatomical studies to define the corticoreticular systems from M1, SMA, and PMd. These studies compare ipsilateral and contralateral sources of corticoreticular projections onto identified reticulospinal neurons. A dual retrograde tracing study from the cervical spinal cord will also show where reticulospinal neurons originate with ipsilateral, contralateral, and bilateral projections to the spinal cord. This line of investigation is of particular relevance for understanding mechanisms of recovery from stroke because contralesional corticoreticular projections have relatively direct access to the impaired limb. Understanding how these systems operate in the normal subject is a pre-requisite to future studies that can clearly define whether this is system is an important alternative pathway for recovery of upper limb function after stroke. No other US laboratory is engaged in studies of this sort in the monkey.

描述（由申请人提供）：皮质脊髓和网状脊髓系统必须配合以控制到达和其他自愿运动，但对这种情况的发生知之甚少。该项目中提出的研究将在清醒中使用神经生理学的联合方法，表现猴子和现代的神经解剖学跟踪研究，扩大对上肢运动的合并皮质脊髓中心和网状脊髓控制的机制和功能的知识。三个皮质运动区域是研究的主题，主要运动皮层（M1），补充运动区域（SMA）和背部前前皮层（PMD）。 M1和SMA是皮质脊髓预测的强大来源。 PMD也是皮质脊髓预测的来源，其活性与全臂伸向运动良好有关。 SMA和PMD是对网状脊髓系统皮质性投影的强大来源。在脑干的庞然大物网状结构（PMRF）中研究了网状脊髓系统。在AIM 1中，单独使用皮质运动区域的电刺激和PMRF，并共同揭示了这些下降系统的输出如何结合起来以控制同侧和对侧臂。也有证据表明，皮质脊髓系统可以竞争阻止网状脊髓系统的产出，这项研究将揭示PMRF输出的皮层门控的方式和地点。即使在单个神经元水平上，该项目也产生了皮质脊髓和网状神经元之间相互作用的证据，并定义这与控制的控制是目标1的最后一部分。在AIM 1的整个研究中，该受试者都用双臂伸直，但一次仅使用一个ARM。 AIM 2采用了不同的设备来需要协调的双层锻炼。在这里，假设是，网状脊髓神经元将具有最佳与PMRF电刺激最常见结果的活性模式，PMRF是具有同侧屈曲和对侧扩展的四肢之间的双重互相模式。 AIM 2的其他电刺激研究还将决定PMRF输出的皮层门控在双边臂量的模式与典型的PMRF输出协同作用的运动相匹配或背离的运动时。 AIM 3采用互补的神经解剖学研究来定义M1，SMA和PMD的皮质系统。这些研究比较了皮质性投影的同侧和对侧来源与已鉴定的网状神经元。颈脊髓的一项双重逆行跟踪研究还将显示网状神经元以同侧，对侧和双侧投射到脊髓。这种调查线与理解中风恢复机制特别相关，因为对比皮层投影相对直接直接访问受损的肢体。了解这些系统如何在正常受试者中运行是未来研究的先决条件，可以清楚地定义该系统是否是中风后上肢功能恢复上肢功能的重要替代途径。在猴子中，没有其他美国实验室从事这种研究。