CEREBRAL CORTICAL MECHANISMS FOR CONTROL OF SACCADES

与脑干控制的高级知识相比 眼球跳动，对大脑皮层如何 Controls的扫视还处于早期阶段。建议的主要目标是 研究是通过分析眼跳的大脑皮质控制 由平均得到的视前电位的时空分布 人类脑电(EEG)记录。这项技术将会 被用来测试大脑皮质控制的三分式模型 眼跳源自当前的知识状态。根据 模型中，弧形额叶眼场(FEF)控制视觉上的自愿性- 相关的眼跳，顶叶有助于 视觉诱发的反射性眼跳的上丘 视觉注意的释放和转移，以及内侧额叶 与基底神经节一起控制自我启动的眼跳 没有视觉目标和抑制不想要的扫视。 该模型将通过测量以下条件下的前馈电势进行测试 具有不同刺激和不同程度自愿控制的条件 在正常受试者和患有影响眼跳的疾病的患者中 入会，包括帕金森氏症和亨廷顿病。除了 获取有关眼跳正常控制的信息，结果是 应该为研究眼球跳动受损的障碍提供基础 控制，以及更多关于电机控制机制的一般知识。 该研究计划的次要目标是开发一种替代方案 前视诱发眼肌电的神经生理学检测 潜力。棘波电位(SP)，眼外病的一种表现 肌肉或眼运动神经活动，将在正常受试者中测试 和眼球运动障碍的患者发展其诊断和 预测能力。

When compared to the advanced level of knowledge about brainstem control of saccadic eye movements, the understanding of how the cerebral cortex controls saccades is in its early stages. The major goal of the proposed research is to study the cortical control of saccades by analyzing the spatio-temporal distribution of presaccadic potentials from averaged electroencephalographic (EEG) recordings in humans. This technique will be employed to test a model for a trichotomy of cortical control of saccades derived from the current state of knowledge. According to the model, the arcuate frontal eye field (FEF) controls voluntary visually- related saccades, the parietal lobe facilitates the performance by the superior colliculus of visually-elicited reflexive saccades by allowing the release and shifting of visual attention, and the medial frontal lobe in conjunction with the basal ganglia govern self-initiated saccades in the absence of visual targets and the suppression of unwanted saccades. The model will be tested by measuring presaccadic potentials under conditions with varying stimuli and varying degrees of voluntary control in normal subjects and patients with diseases affecting saccadic initiation, including Parkinson's and Huntington's diseases. Aside from gaining information about the normal control of saccades, the results should provide a foundation for studying disorders with impaired saccadic control, and further knowledge about motor control mechanisms in general. A secondary goal of the research program is to develop an alternative neurophysiologic test to ocular electromyography with presaccadic potentials. The spike potential (SP), a manifestation of extraocular muscle or ocular motor nerve activity, will be tested in normal subjects and patients with ocular motility disorders to develop its diagnostic and prognostic capabilities.