Role of cerebellar parallel fibers in saccade accuracy

小脑平行纤维在眼跳准确性中的作用

基本信息

批准号：
8111855
负责人：
FARREL R ROBINSON
金额：
$ 41.19万
依托单位：
UNIVERSITY OF WASHINGTON
依托单位国家：
美国
项目类别：
财政年份：
2008
资助国家：
美国
起止时间：
2008-08-01 至 2013-07-31
项目状态：
已结题

项目摘要

Description (provided by applicant): This research will test 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 arrival time of this signal, and consequently the onset of the deceleration that makes saccades accurate, is set by the amount of time it takes the signal to travel from one place in the cerebellum, across the midline, to another part on the other side. We will test this proposal by cutting saccade-related p-fibers. If this idea is right, then the lesion will: 1) abolish the cerebellum signal that helps stop saccades on time; 2) make saccade deceleration abnormally slow; 3) make saccades overshoot their targets. Preliminary data show that the lesion causes all three predicted effects. A corollary of our proposal is that large saccades are represented laterally in the saccade part of the cerebellum and small saccades are represented medially. This is consistent with earlier findings. 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 very different connections. Describing this will tell us how the cerebellum makes movements of different sizes. If, like our pilot results, the work proposed here supports our proposal, then it will provide a basic framework for how the cerebellum transforms the saccade-related signals that it receives into the signals that it uses to 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 remove tumors without impairing vision. Such improvements could help patients quickly because they require no other innovations. PUBLIC HEALTH RELEVANCE The proposed work will explain why eye movements, and consequently vision, are badly impaired in children after surgery to remove the most common brain tumor in children. This explanation will motivate and guide improvements in the surgery so that it removes these tumors without impairing vision. In addition, this work will provide the clearest description yet of how the cerebellum transforms input into signals that make movement, in this case eye movement, accurate.

描述（由申请人提供）：这项研究将测试一个简单，合理且新颖的建议，内容涉及小脑如何使自愿的快速眼动（扫视）准确。我们建议扫视精度取决于在正确时间停止扫视的信号。该信号在称为平行纤维（P纤维）的轴突中跨越小脑的中线。该信号的到达时间以及使扫视准确的减速的发作是由信号从小脑中的一个地方，穿过中线到另一侧的另一部分的信号所花费的时间设置的。我们将通过切割扫视相关的P纤维来测试该建议。如果这个想法是正确的，那么病变将：1）废除有助于按时停止扫视的小脑信号； 2）使扫视减速异常缓慢； 3）使扫视超出目标。初步数据表明，病变会导致所有三个预测影响。我们提议的必然性是，大扫视在小脑的扫视部分横向表示，而小扫视的内侧表示。这与早期发现一致。我们将使用解剖学跟踪来描述该区域外侧和内侧部分的连接，以确定这些连接如何导致不同尺寸的运动。初步数据表明，小脑扫视部分的横向和内侧区域具有截然不同的连接。描述这将告诉我们小脑如何使大小不同。如果像我们的试点结果一样，这里提出的工作支持我们的建议，那么它将为小脑如何转换其接收到的扫视相关信号的基本框架，这些信号将其用于使扫视准确的信号。这项工作还将表明为什么扫视和视力受到手术的严重损害，以清除儿童最常见的脑肿瘤。这将激发和指导易于实施治疗和手术的修改，以消除肿瘤而不会损害视力。这样的改进可以快速帮助患者，因为他们不需要其他创新。公共卫生相关性拟议的工作将解释为什么手术后儿童的眼动运动及其视力受到严重损害，以消除儿童最常见的脑肿瘤。这种解释将激发和指导手术的改进，从而消除这些肿瘤而不会损害视力。此外，这项工作将提供最清晰的描述，说明小脑如何将输入转化为信号，在这种情况下，在这种情况下，在这种情况下，眼睛移动准确。