PHYSIOLOGICAL ANALYSIS OF VOLUNTARY MOVEMENT

随意运动的生理分析

• 批准号: 6290633
• 负责人: MARK A HALLETT
• 金额: --
• 依托单位: NATIONAL INSTITUTE OF NEUROLOGICAL DISORDERS AND STROKE
• 依托单位国家: 美国
• 资助国家: 美国
• 起止时间: 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/6290633
• 关键词: Parkinson's disease; body movement; brain electrical activity; buspirone; cerebellar disorders; cerebellum; clinical research; dystonia; electroencephalography; evoked potentials; functional magnetic resonance imaging; gait; glycine; hemiplegia; human subject; limb movement; mathematical model; motor neurons; neural plasticity; neuromuscular disorder; positron emission tomography; progressive supranuclear palsy; proprioception /kinesthesia; sensory feedback

The goal of this project is to learn more about the control of movement in normal humans and in patients with voluntary movement disorders such as Parkinsons disease, cerebellar ataxia, hemiplegia from stroke and dystonia. One major scientific target of the Branch is to understand and possibly influence cortical reorganization in patients with congenital or acquired lesions of the central nervous system. A multi- modality approach (neuroimaging with PET and functional MRI, EEG, and transcranial magnetic stimulation) is being used to determine patterns of long-term reorganization of functional brain topography in individual stroke patients. Analysis of data from patients with subcortical lesions indicated that the reoganization of the cortical activity and excitability patterns depends on the site of the lesion within the internal capsule. Spectral power and coherence analyses of EEG are being employed to see how the brain communicates during different tasks. We have looked at EEG-EMG coherence to explore the motor cortex control of muscle. The cortico-muscular coherence in the higher frequencies (14-50 Hz) is mediated by the fast corticospinal tract and that coherence in the lower frequencies (3-13 Hz) is probably generated by a subcortical rhythm generator. The peak coherence value was not significantly affected by the produced force. However, a cortical-muscular coherence within the gamma band appeared as the strength of contraction increased up to 60% or more. This gamma band coherence at the higher force level most likely reflects the cortical control of the firing-rate modulation of the motor units and explains the generation of the muscle Piper rhythm, the 40 Hz grouping of muscle action potentials during maximal contraction. EEG coherence between the sensorimotor cortices on the two sides of the brain is similar for unimanual and bimanual tasks, but increases transiently when a new bimanual task is learned. In a study of bimanual coordination using fMRI, we found that areas which showed significantly more activation with antiparallel than parallel movement were the right SMA, the caudal cingulate motor area bilaterally and the right lateral premotor cortex. We have also studied different aspects of motor learning using PET and fMRI. Using PET, we confirmed prior EEG findings that the normal homuncular organization of the primary sensory cortex is degraded in patients with focal dystonia supporting the concept that sensory abnormalities play a pathogenetic role in dystonia. We have continued to treat patients with focal dystonias with botulinum toxin and demonstrate that patients with antibodies to type A can respond to type F. We studied a group of patients with Friedreichs ataxia using a new MRI sequence for iron and demonstrated an increased iron content in the dentate nucleus of the cerebellum consistent with the idea that iron is important in the pathophysiology. - Parkinson's disease, stroke, dystonia, EEG, positron emission tomography, functional MRI, ataxia, movement - Human Subjects

该项目的目标是更多地了解正常人和自主运动障碍患者的运动控制，如帕金森病，小脑共济失调，中风偏瘫和肌张力障碍。分支的一个主要科学目标是了解并可能影响先天性或后天性中枢神经系统病变患者的皮质重组。多模态方法（PET和功能性MRI神经成像、EEG和经颅磁刺激）用于确定个体卒中患者功能性脑地形图的长期重组模式。对皮质下病变患者的数据分析表明，皮质活动和兴奋性模式的重新组织化取决于内囊内病变的部位。EEG的频谱功率和相干性分析正在被用来研究大脑在不同任务中的通信方式。我们已经研究了EEG-EMG相干性，以探索肌肉的运动皮层控制。高频（14-50 Hz）的皮质-肌肉相干性由快皮质脊髓束介导，低频（3-13 Hz）的相干性可能由皮质下节律发生器产生。峰值相干性值不受所产生的力的显著影响。然而，当收缩强度增加到60%或更多时，γ带内出现皮质-肌肉一致性。在更高的力量水平上的这种伽马带的连贯性最有可能反映了皮层对运动单元的发射率调制的控制，并解释了肌肉Piper节律的产生，最大收缩期间肌肉动作电位的40 Hz分组。在单手和双手任务中，大脑两侧感觉运动皮层之间的EEG相干性是相似的，但是当学习新的双手任务时，EEG相干性会短暂增加。在一项使用fMRI研究双手协调性的研究中，我们发现，与平行运动相比，反平行运动显示出明显更多激活的区域是右侧SMA、双侧尾侧扣带回运动区和右侧运动前区皮质。我们还使用PET和fMRI研究了运动学习的不同方面。使用PET，我们证实了先前的EEG结果，即在局灶性肌张力障碍患者中，初级感觉皮层的正常球状组织被降解，这支持了感觉异常在肌张力障碍中起致病作用的概念。我们继续用肉毒杆菌毒素治疗局灶性肌张力障碍患者，并证明具有A型抗体的患者可以对F型产生反应。我们研究了一组患者Friedreichs共济失调使用一种新的MRI序列的铁，并证明了铁含量增加的小脑齿状核与铁是重要的病理生理学的想法一致。- 帕金森病、中风、肌张力障碍、EEG、正电子发射断层扫描、功能性MRI、共济失调、运动-人类受试者