Brainstem-cerebellar Interactions in Gaze Control

项目1：在执行复杂行为的过程中，产生平稳协调的运动是神经系统的基本目标。要做到这一点，必须不断地整合感觉信息，以构建世界上物体的表征。这一关键功能需要能够区分自身产生的运动和物体运动，整合不同的感觉信息，并计划和执行同步的运动行为。调节协调动作选择和执行的神经结构之间的相互作用，以及解决稳定反射和运动指令之间内在冲突的机制，是理解协调动作的神经控制的关键问题。协调眼头运动的神经控制是一个实验系统。 这为调节视觉定向行为的神经机制提供了重要的见解。将视线(凝视)指向有趣的物体会增强我们对物体的感知，并提供一种构建和维护世界内部模型的方法。这些凝视方向的改变通常是通过协调眼睛和头部来完成的，为研究定向行为的神经控制、多个身体部分的协调、空间定向以及感觉信息到运动指令的转换提供了一个很好的模型系统。这项研究的目的是阐明视觉定向运动中协调所需的神经计算和机制。长期以来，小脑一直与运动指令的精炼和纠正指令与执行动作之间的错误有关。视觉定向行为中眼头协调的脑干控制一直是并将继续是本实验室的主要研究重点。这里提出的实验扩展了这项工作，以调查小脑在修改和/或纠正脑干区域产生的运动命令中的作用。这项拟议的研究将测试顶核的尾部和吻部在协调眼睛和头部运动方面的不同作用。实验还将检验这一假设，即上丘活动产生的凝视转移指令是通过尾侧顶核(CFN)的活动来改进的。该实验室研究的主要目标是了解协调行动的神经机制。这些机制的中断可由中风或疾病引起，并经常造成破坏性后果，如空间定向障碍、眼球运动障碍和/或共济失调。拟议的研究将有助于及早发现干扰，并导致这些障碍的新治疗方法。

Project 1: Producing smoothly coordinated movements during performance of complex behaviors is an essential goal of the nervous system. To accomplish this, sensory information must be integrated continuously in order to construct a representation of objects in the world. This critical function requires the ability to distinguish between self-generated and object motion, to integrate diverse sensory information, and to plan and execute simultaneous motor behaviors. The interactions among neural structures that mediate selection and execution of coordinated movements, and the mechanisms that resolve the inherent conflict between stabilizing reflexes and motor commands are critical issues in understanding the neural control of coordinated action. The neural control of coordinated eye-head movements is an experimental system that has provided significant insights into the neural mechanisms mediating visual orienting behaviors. Directing the line of sight (gaze) towards interesting objects enhances our perception of the object and provides a way to construct and maintain an internal model of the world. These changes in gaze direction are generally accomplished by coordinating the eyes and head, and provide an excellent model system for studying the neural control of orienting behaviors, the coordination of multiple body segments, spatial orientation and transformation of sensory information into motor commands. The goals of the proposed research are to elucidate the neural computations and mechanisms required for coordination within the context of visual orienting movements. The cerebellum has long been implicated in the refinement of motor commands and correction of errors between commanded and executed movements. The brainstem control of eye-head coordination during visual orienting behaviors has been and continues to be a major focus of research in this lab. The experiments proposed here extend this work in order to investigate the role of the cerebellum in modifying and/or correcting the motor commands generated by brainstem regions. The proposed research will test the differential roles of the caudal and rostral portions of the fastigial nucleus in coordinating movements of the eyes and head. Experiments will also test the hypothesis that gaze shift commands generated by activity in the superior colliculus are refined by activity in the caudal fastigial nucleus (cFN). The primary goals of the research in the lab are to understand the neural mechanisms mediating coordinated actions. Disruption of these mechanisms can result from stroke or disease and often have devastating consequences such as spatial disorientation, saccadic dysmetria and/or ataxia. The proposed research will facilitate early detection of disturbances and lead to new treatments of these disorders.