CORTICOTECTAL CIRCUITS IN VISUAL PROCESSING

在哺乳动物中，几乎所有的视觉皮层区域都发出大量的投射， 到上级丘，一个与选择性注意有关的结构 以及眼睛和头部运动的开始。 虽然生理和 这种皮质-顶盖通路的解剖学已经被广泛研究， 对选择性注意和视觉行为的贡献实际上是 因为大多数研究使用的是瘫痪的、麻醉的动物。 我们建议研究逆行鉴定的皮质顶盖的活性， 后内侧外侧上皮层17、18、7区神经元 （PMLS），以及受过视觉训练的警觉猫的额叶视野 任务 我们将把皮质顶盖细胞的前扫视活动与 空间定向注意力 我们将检查眼跳过程中的活动 为了阐明皮质顶盖细胞在这些现象中的可能作用， 扫视抑制，区分真实的运动和视运动，以及 更新视网膜坐标和空间坐标之间的关系。 我们将 确定神经元的兴奋性在多大程度上取决于 凝视的角度。 对眼睛位置敏感的神经元提供了一种机制， 在以头部为中心的参照系中编码视觉空间。 检查 皮层不同区域皮质顶盖细胞的反应特性 将深入了解多个视觉区域对 丘功能 本项目的长期目标是确定 视觉皮层对选择性注意和控制的作用 目光

In mammals, virtually all areas of visual cortex send a massive projection to the superior colliculus, a structure associated with selective attention and the initiation of eye and head movements. Although the physiology and anatomy of this corticotectal pathway have been studied extensively, its contribution to selective attention and visuomotor behavior are virtually unknown because most studies have used the paralyzed, anaesthetized animal. We propose to study the activity of antidromically identified corticotectal neurons in areas 17, 18, 7, posteromedial lateral suprasylvian cortex (PMLS), and the frontal eye fields of alert cats trained in visuomotor tasks. We will relate the pre-saccadic activity of corticotectal cells to spatially directed attention. We will examine activity during the saccade to elucidate the possible role of corticotectal cells in such phenomena as saccadic suppression, distinguishing real from apparent movement, and updating relations between retinal and spatial coordinates. We will determine to what extent the excitability of the neuron is dependent on angle of gaze. Neurons sensitive to eye position provide a mechanism for encoding visual space in a head-centered frame of reference. Examining response properties of corticotectal cells in different areas of cortex will provide insight into the contribution of multiple visual areas to collicular function. The long-range goal of this project is to determine the contribution of visual cortex to selective attention and control of gaze.