SACCADIC EYE MOVEMENT STUDIES

描述：这项研究的长期目标是了解 神经系统如何将感觉信息转化为命令 用于启动和执行动作。私家侦探使用了跳动的 眼动系统由于其简单的外周而被用作研究的模型 机械学和肌肉学，以及眼球运动的简易性 快速准确地记录下来。由于这些优势， 扫视系统相对较好地理解在它的 组成神经元的类型、它们的放电模式以及它们的许多 关系。尽管如此，与最近大量的工作相比 在更多的中枢跳动结构(如皮质)上，有一些 关于脑干眼跳发生器的基本问题 没有被处理过。私家侦探建议继续调查 眼跳生成器通过检查这两个基本的，重要的领域。 首先，几乎所有的组织模型(即假设) 眼跳发生需要舌下前置核(NPH) 提供眼部位置、眼部速度或更复杂的信号 扫视生成器中的其他元素。PI正在测试效果 在扫视中对结构的破坏，并将继续这些 通过两种方式进行实验。一类NPH神经元--“爆发式驾驶” 神经元“被认为提供了一种重要的兴奋性驱动力 猫身上的扫视生成器。为了测试这一点的有效性 建议，在一个实验中，他将描述这些物质的放电 训练过的猴子体内的神经元。在另一系列实验中，他将 扩展NPH损害影响的测试，通过检查非 NPH损害导致的眼球运动障碍 更好地确定动眼神经的神经底物 积分器，眼跳生成器的另一个关键元素。 第二个要研究的区域是吻侧脑桥。而上级 丘脑长期以来一直与眼跳的产生有关，它是 对于眼跳生产来说不是必需的。因此，另一种结构必须 或者调解其影响，或者能够在 丘脑受损。一个明显的候选者是嘴桥，它 接受丘脑和皮质的输入。私人投资委员会将审查 脑桥头端神经元放电的计量学和定量研究 按顺序将放电与扫视和目标指标相关联 来发现这些神经元是否会在 假设的扫视信号或必须合并的新信号 演变成眼跳生成的进化模型。他还将测试这些 从丘脑区或皮质区输入的神经元通过电刺激 刺激。 这些研究应该提供一个例子，说明神经系统是如何 将视觉感觉信息处理成跳动反应。在……里面 此外，具有扫视功能的结构和 眼球运动可以被准确监测的简便性 经证实，并应继续非常有用的诊断和 由多种原因引起的神经系统功能障碍的定位 原因。

DESCRIPTION: The long-term objective of this research is to understand how the nervous system translates sensory information into the commands for initiation and execution of movements. The PI has used the saccadic eye movement system as a model for study because of its simple peripheral mechanics and musculature and the ease with which eye movements can be quickly and accurately recorded. Because of these advantages, the saccadic system is comparatively well understood in terms of its component neuron types, their discharge patterns, and many of their connections. Nonetheless, in contrast to the abundance of recent work on more central saccadic structures (e.g., cortex), there are a number of fundamental questions about the brainstem saccade generator that have not been addressed. The PI proposes to continue investigations of the saccade generator by examining two of these basic, important areas. First, virtually all models (i.e., hypotheses) of organization of the saccade generator require the nucleus prepositus hypoglossi (nph) to provide either eye position, eye velocity, or more complex signals to other elements in the saccade generator. The PI is testing the effect of damage to that structure on saccades and will continue these experiments in two ways. A class of nph neurons, the "burster driving neurons" has been suggested to provide an important excitatory drive to the saccade generator in the cat. To test the validity of this suggestion, in one experiment he will describe the discharge of these neurons in the trained monkey. In another series of experiment, he will expand the tests of the effects of nph damage by examining the non- saccadic eye movement deficits that result from nph lesions in order to better define the neural substrate for the oculomotor neuronal integrator, another pivotal element of the saccade generator. The second region to be studied is the rostral pons. While the superior colliculus has long been implicated in the generation of saccades, it is not essential for saccade production. Therefore, another structure must either mediate its effects or be able to substitute for it when the colliculus is damaged. An obvious candidate is the rostral pons which receives collicular as well as cortical inputs. The PI will examine the metrics of the discharge rostral pontine neurons and quantitatively correlate that discharge with the saccade and target metrics in order to discover whether these neuron might code either previously hypothesized saccade signals or new signals that must be incorporated into evolving models of saccade generation. He will also test these neurons for input from collicular or cortical areas by using electrical stimulation. These studies should provide an example of how the nervous system processes visual sensory information into saccadic motor responses. In addition, the co-localization of structures with saccadic functions and the ease with which eye movements can be accurately monitored has proven, and should continue to be very useful in the diagnosis and localization of nervous system dysfunction resulting from a wide variety of causes.