CEREBELLAR NUCLEI IN EYE MOVEMENT CONTROL AND ADAPTATION

平滑的追踪和扫视眼球运动需要非常准确， 提供视觉目标的清晰视网膜图像。小脑病变 严重损害眼球运动的每时每刻的准确性， 当大脑或周边受到损伤时， 使他们不协调。虽然小脑显然是不可或缺的， 眼动的准确性和适应性，其具体作用是 不清楚这项拟议中的研究将提供重要的新信息 关于小脑在平稳追踪和扫视眼球运动中的作用 通过研究小脑核团中的两个区域， 涉及到他们的控制，尾顶核（CFN）和 腹外侧间位核（VPIN）。 我们有三个目标。首先，我们将描述CFN的作用， 追求我们将描述CFN神经元在各种情况下的反应。 我们将在短暂的追踪之后测量追踪情况， 用GABA激动剂蝇蕈醇灭活GFN神经元。这些结果 会告诉我们CFN的活动是否可以支持追捕行动， 以及这种行为实际上如何影响追求。二是 将调查的VPIN的作用，在追求和扫视眼球运动。我们 将描述这些运动过程中VPIN神经元的反应， 描述用蝇蕈醇灭活VPIN如何影响追踪， 扫视初步结果表明，VPIN中的神经元对 在扫视过程中与CFN神经元不同，表明它们 执行不同的功能。我们的数据可以让我们直接比较 这两个区域的神经元来理解为什么 小脑在相同的运动中是活跃的。第三，我们会决定 如果CFN或VPIN对于适应扫视增益是必要的。我们 将测量适应率之前和之后，我们将其中之一， 与muscimol。如果这损害了适应性，我们将从 神经元在关键领域（S）在适应，看看他们如何 响应特性随增益改变而改变。以前的研究表明，一些 小脑核的一部分是扫视适应所必需的， 不确定关键区域。GFN和VPIN是最有可能的区域 因为它们是核中唯一已知的与扫视相关的区域。 通过描述CFN和VPIN在追踪、扫视和运动中的作用， 扫视适应这项工作将帮助我们了解小脑 有助于整体运动。

Smooth pursuit and saccadic eye movements need to be extremely accurate to provide clear retinal images of visual targets. Lesions of the cerebellum severely impair both the moment-to-moment accuracy of eye movements and the ability to adapt eye movements when damage to the brain or periphery makes them inaCCurate. Though the cerebellum is clearly indispensable to the accuracy and adaptation of eye movements, its specific role is unclear. The proposed research will provide significant new information about the role of cerebellum in smooth pursuit and saccadic eye movements by studying the two regions in the cerebellar nuclei most strongly implicated in their control, the caudal fastigial nucleus (CFN) and the ventrolateral interpositus nucleus (VPIN). We have three goals. First, we will characterize the CFN's role in pursuit. We will describe the responses of CFN neurons during a variety of pursuit conditions and we will measure pursuit after temporarily inactivating GFN neurons with the GABA agonist muscimol. These results will tell us if CFN activity could support pursuit initiation and maintenance and how this activity, in fact, affects pursuit. Second, we will investigate the VPIN's role in pursuit and saccadic eye movements. We will characterize the responses of VPIN neurons during these movements and describe how inactivating the VPIN with muscimol affects pursuit and saccades. Preliminary results show that neurons in the VPIN respond differently during saccades than do CFN neurons indicating that they perform a different function. Our data will allow us to directly compare neurons in these two regions to understand why two separate parts of the cerebellum are active during the same movements. ThIrd, we will determine if either the CFN or the VPIN is necessary for adapting saccade gain. We will measure adaptation rate before and after we inactivate one of these areas with muscimol. If this impairs adaptation we will record from neurons in the critical area(s) during adaptation to see how their response properties alter as gain changes. Previous work shows that some part of the cerebellar nuclei is necessary for saccade adaptation but does not identify the critical area. GFN and VPIN are the most likely areas because they are the only known saccade-related regions of the nuclei. By describing the role of CFN and the VPIN in pursuit, saccades, and saccade adaptation this work will help us understand what the cerebellum contributes to movements in general.