Role of neural variation in smooth pursuit eye movements

顺畅的追逐眼球运动是一种众所周知的行为，具有已知的神经基础。追求就是 当目标平稳移动时生成。它依赖于带有输入的传统皮质-小脑回路。 来自感觉皮质，顶叶感觉运动区的处理，以及来自额叶运动的运动指令 区域。大脑皮层的输出与大脑-小脑环路和大脑-基底节相互作用 用于生成电机命令的电路。我们对这些区域神经元的平均反应知之甚少。 以及他们如何促成了普通追逐运动的产生。然而，分析了 神经编码和追逐行为的变化打开了一个新的景象。对于追求的感官输入是高度的 变量，但行为本身非常精确。量化变化的存在和简便性 神经信号和行为提供了询问神经变异在连续体中的位置的机会 不再是行为神经生成的消极、中性或积极的组成部分。这个项目将 聚焦于眼球跳动前部视野附近的前部追踪区(FPA)，将提出3个问题，分别是 与孔特神经科学研究中心的目标紧密相连。首先，它会询问 FPA中的神经代码各不相同，方差的多少部分1)与行为有关，2) “残留物”，与行为无关。这些分数在追求的不同阶段是如何变化的 有动静？其次，它将使用差别奖惩来调节行为的分布 并探索FPA中神经变异的变化如何影响这种变异。第三，它 将探索FPA在追逐中视觉指导学习的教学期间的神经变异， 以及在随后的学习表达过程中。本项目的研究将有助于整体的 CCNR的目标，通过提供一个模范行为，在那里可以狭义地定义定量的问题 回答了神经变异在严格控制和众所周知的行为中的具体作用。在……里面 此外，对额叶皮质如何控制追踪的理解可能有助于我们理解为什么 精神分裂症患者在顺畅追踪眼球运动方面存在严重缺陷。

Smooth pursuit eye movements are a well-understood behavior with a known neural substrate. Pursuit is generated when a target moves smoothly. It depends on a traditional cortical-cerebellar circuit with inputs from sensory cortex, processing in parietal sensory-motor areas, and motor commands from a frontal motor area. Outputs from the cerebral cortex interact with cerebro-cerebellar circuits and cerebro-basal ganglia circuits to generate motor commands. Much is known about the mean responses of neurons in these areas and how they contribute to the generation of the average pursuit movement. However, the analysis of variation in neural codes and pursuit behavior opens a new vista. The sensory input for pursuit is highly variable, yet the behavior itself is remarkably precise. The presence and ease of quantifying variation in the neural signals and the behavior offers the opportunity to ask where neural variation falls on the continuum from being a negative, neutral, or positive component of the neural generation of behavior. This project will focus on the frontal pursuit area (FPA), near the saccadic frontal eye fields and will ask 3 questions that are tightly linked to the aims of the Conte Center for Neuroscience Research. First, it will ask how much the neural code in the FPA varies and what fractions of the variance are 1) related to the behavior and 2) "residual", unrelated to the behavior. How do these fractions vary over the different phases of a pursuit movement? Second, it will use differential reward and penalty to modulate the distribution of behavioral variation and explore how that variation is effected by changes in the neural variation in the FPA. Third, it will explore neural variation in the FPA during the instructional period for visually-guided learning in pursuit, and during the subsequent expression of learning. The research in this project will contribute to the overall goals of the CCNR by providing an exemplar behavior where narrowly defined, quantitative questions can be answered about the specific roles of neural variation in a tightly controlled and well-understood behavior. In addition, an understanding of how the frontal cortex controls pursuit may help us to understand why schizophrenics have such profound deficits in smooth pursuit eye movements.