PHYSIOLOGICAL ANALYSIS OF VOLUNTARY MOVEMENT

为了理解复杂动作背后的过程， 我们正在研究不同长度的连续运动。 在一项研究中 通过PET，我们确定运动前皮质与 增加序列的长度。 随着EEG的增加， 中央和额叶区域之间的一致性检测到更多 复杂的手指动作。 为了理解运动学习，我们研究了 感觉运动区在内隐和外显习得中的作用 使用EEG的顺序反应时间任务中的外显知识。 那里 最大程度地降低了 对侧感觉运动区在发展的时间充分 显性知识使用功能性MRI（fMRI），我们研究了 辅助运动区（SMA）和前扣带回的参与 大脑皮层（ACC）在自主起搏与外部触发运动动作中的作用 在连续的运动中。 简单顺序远端 运动激活SMA和ACC，信号变化较大 在自我节奏的强度比触发运动。 在盲人中，在盲文阅读过程中， 用正电子发射断层扫描和功能磁共振成像 这表明 皮质可塑性显著 帕金森病患者调整他们的动作， 总是产生比预期小的运动。 研究表明 这可能是由于动觉受损 研究工作集中在感觉反馈在大脑中的作用。 小脑变性患者的运动控制。 一 多输入多输出反馈控制系统能够建模 站立的人体对脉冲扰动的反应 适用于背部。小脑变性患者的能力 感知运动觉刺激的差异被发现是有缺陷的 在完全被动的任务中。研究使用的任务需要 多关节协调已经完成，这表明， 小脑患者的运动表现在很大程度上是由于长期的 反应时间 共济失调的临床评定量表已经开发出来 这与小脑解剖异常的程度有关 和磁共振光谱成像。 我们研究了遗传性反射亢进的患者， 被认为是由甘氨酸介导的。反射通路认为 由甘氨酸能Ia型中间神经元介导的表达异常， Renshaw细胞，提示可能的代偿性变化。二反射 被认为是由GABA介导的通路是正常的。

To understand processes underlying the performance of complex movements, we are studying sequential movements of differing length. In a study with PET we determined that premotor cortex was most related to increasing length of the sequence. With EEG, greater increases in coherence between central and frontal regions were detected for more complex finger movements. To understand motor learning, we have studied the role of sensorimotor areas in the acquisition of implicit and explicit knowledge in a sequential reaction time task using EEG. There was maximal desynchronization of the alpha activity over the contralateral sensorimotor area at the time of development of full explicit knowledge. Using functional MRI (fMRI), we studied the participation of supplementary motor area (SMA), and anterior cingulate cortex (ACC) in self-paced versus externally-triggered motor actions during sequential movements. Performance of simple sequential distal movements activates the SMA and ACC, with a larger change of signal intensity in self-paced than in triggered movements. In blind people, during Braille reading, activation has been found in the primary occipital area using both PET and fMRI. This indicates remarkable cortical plasticity. Patients with Parkinson's disease scale their movements so that they always produce a movement smaller than desired. Studies demonstrated that this might be due to an impairment in kinesthesia. Research efforts have focussed on the role of sensory feedback in the control of movements in patients with cerebellar degenerations. A multiinput-multioutput feedback control system is capable of modelling the response of the standing human body to impulsive perturbations applied to the back. The ability of patients with cerebellar degeneration to perceive differences in kinesthetic stimuli was found to be defective in tasks that were entirely passive. Studies using a task requiring multijoint coordination have been completed which suggest that deficits in motor performance in cerebellar patients is largely due to prolonged reaction times. A clinical rating scale for ataxia has been developed which correlates with the degree of cerebellar abnormality on anatomic and magnetic resonance spectroscopic imaging. We studied patients with hereditary hyperekplexia to see if reflexes thought to be mediated by glycine were affected. Reflex pathways thought to be mediated by glycinergic Ia interneurons were abnormal, but not Renshaw cells, suggesting possible compensatory changes. Two reflex pathways thought to be mediated by GABA were normal.