CORTICOTECTAL CIRCUITS IN VISUAL PROCESSING

在哺乳动物中，视觉皮质的几乎所有区域都会发出巨大的投射 上丘，这是一种与选择性注意相关的结构 以及启动眼睛和头部的运动。虽然生理学和 对这条皮质顶盖通路的解剖已经进行了广泛的研究，其 对选择性注意和视觉运动行为的贡献实际上是 未知，因为大多数研究都使用了瘫痪、麻醉的动物。 我们建议研究逆行鉴定的皮质顶盖的活性。 17区、18区、7区、后内侧外侧丘上皮质神经元 (PMLS)，以及经过视觉运动训练的警觉猫的前部眼场 任务。我们将把皮质顶盖细胞的眼球跳前活动与 空间定向的注意力。我们将检查扫视过程中的活动 为了阐明皮质顶盖细胞在以下现象中的可能作用 眼跳抑制，区分真实和明显的运动，以及 更新视网膜和空间坐标之间的关系。我们会 确定神经元的兴奋性在多大程度上取决于 凝视角度。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。检视 皮质不同区域皮质顶盖细胞的反应特性 将深入了解多个可视区域对 集合体功能。这个项目的长期目标是确定 视皮层在选择性注意和控制中的作用 凝视。

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.