ROLE OF CEREBELLAR PARALLEL FIBERS IN SACCADE ACCURACY

这个子项目是许多研究子项目中的一个 由NIH/NCRR资助的中心赠款提供的资源。子项目及 研究者（PI）可能从另一个NIH来源获得了主要资金， 因此可以在其他CRISP条目中表示。所列机构为 研究中心，而研究中心不一定是研究者所在的机构。 这项研究测试了一个简单、合理、新颖的关于小脑如何使自愿快速眼球运动（扫视）准确的提议。 我们建议，扫视准确性取决于在正确的时间停止扫视的信号。 这种信号在小脑中线的轴突中传播，称为平行纤维（p纤维）。 扫视减速的开始由信号行进到另一侧的目的地所花费的时间量来设置。 我们将通过切断扫视相关的p纤维来测试这个提议。 如果这个想法是正确的，那么这个切割将：1）消除小脑信号，及时停止扫视; 2）使扫视减速异常缓慢; 3）使扫视超过他们的目标。 初步数据显示，这一切割导致了所有三种效应。 我们的建议的一个必然结果是，大的眼跳是横向的眼跳相关的小脑的一部分，而小的眼跳是代表中间。 我们将使用解剖追踪来描述该区域的外侧和内侧部分的连接，以确定这些连接如何引起不同大小的运动。 初步数据显示，小脑扫视部分的外侧和内侧区域形成不同的连接。 描述这一点将告诉我们小脑如何做出不同大小的运动。 如果我们的结果支持我们的提议，那么它将为小脑如何将其接收到的与扫视相关的信号转换为使扫视准确的输出信号提供一个基本框架。 这项工作也将表明为什么扫视，因此视力，是严重损害的手术，以消除最常见的脑肿瘤的儿童。 这将激励和指导易于实施的治疗和手术修改，以在不损害视力的情况下切除肿瘤。 这些改进可以快速帮助患者，因为它们不需要其他创新。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. This research tests a simple, plausible, and novel proposal about how the cerebellum makes voluntary rapid eye movements (saccades) accurate. We propose that saccade accuracy depends on a signal that stops saccades at the right time. This signal travels across the midline of the cerebellum in the axons called parallel fibers (p-fibers). The onset of saccade deceleration is set by the amount of time it takes the signal to travel to its destination on the other side. We will test this proposal by cutting saccade-related p-fibers. If this idea is right, then this cut will: 1) abolish the cerebellum signal that stops saccades on time; 2) make saccade deceleration abnormally slow; 3) make saccades overshoot their targets. Preliminary data show that this cut causes all three effects. A corollary of our proposal is that large saccades are represented laterally in the saccade-related part of the cerebellum while small saccades are represented medially. We will use anatomical tracing to describe the connections from lateral and medial parts of this region to determine how these connections cause movements of different sizes. Preliminary data show that the lateral and medial areas of the saccade part of the cerebellum make different connections. Describing this will tell us how the cerebellum makes movements of different sizes. If our results support our proposal, then it will provide a basic framework for how the cerebellum transforms the saccade-related signals that it receives into the output signals that make saccades accurate. This work will also show why saccades, and consequently vision, are badly impaired by surgery to remove the most common brain tumors in children. This will motivate and guide easy-to-implement modifications of treatment and surgery to removes tumors without impairing vision. Such improvements could help patients quickly because they require no other innovations.