ORGANIZATION OF EXTRASTRIATE VISUAL CORTEX

外纹视觉皮层的组织

• 批准号: 2159164
• 负责人: Helen A. Sherk
• 金额: $ 16.71万
• 依托单位: UNIVERSITY OF WASHINGTON
• 依托单位国家: 美国
• 财政年份: 1983
• 资助国家: 美国
• 起止时间: 1983-07-01 至 1996-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2159164
• 关键词: brain mapping; cats; chordate locomotion; computer simulation; experimental brain lesion; neural information processing; single cell analysis; visual cortex; visual pathways; visual perception; visual stimulus

Much effort has been invested in exploring the basis of mammalian visual pattern perception. Another important visual function that has received far less attention is visual analysis during locomotion. The goal of this proposal is to study this function using single cell recording methods in the cat. The cat is a good model for three reasons. Its visual system in many respects resembles that of primates. Like humans, the cat is basically terrestrial, and thus must solve similar problems during locomotion. Moreover, extensive evidence suggests that one area of the cat's extrastriate cortex, the lateral suprasylvian area (LS), may play a major role in vision during locomotion. A novel visual display system has been developed, based on a Next computer, in order to present stimulus displays that simulate the visual scene during locomotion. The display is large, subtending about 60 degrees horizontally, so as to adequately stimulate the very large "silent surrounds" typical of cells in LS. A wide-field version of the display will be used to ask how a cell's response to a moving stimulus is affected by placing the stimulus in the context of an optic flow field, and how manipulation of different parameters of the optic flow affect cell responses. A smaller version of the display, containing a high density of moving images, will be used to ask whether cells respond to stimuli that differ from their neighbors, and might represent obstacles or irregularities in terrain. The same displays will be used to test responses in area 19, an extrastriate area that has connections very similar to those of LS, but that has quite different response properties. The hypothesis is that responses in area 19 to optic flow simulations will be poor or non-specific since its response properties do not suggest any role in visual analysis during locomotion. The source of the large "silent surrounds" in LS, which may contribute to analysis of optic flow fields, will be examined with two approaches. The major thalamic input to LS will be removed, since the response properties of this input suggest that it is a likely source of wide-field effects. Response properties in LS will then be tested. Intrinsic connections within LS will be studied to see whether their distribution can be explained on retinotopic grounds, or instead might contribute to wide- field inhibition and/or facilitation. This project will fill a major gap in our understanding of visual function at the level of single cell behavior. Ultimately, a clear understanding of normal visual cortical function will provide insight into the underlying causes of visual dysfunction resulting from damage to the cerebral cortex.

在探索哺乳动物视觉的基础上已经投入了很多努力 模式感知。 已接收的另一个重要的视觉功能 运动过程中的视觉分析要少得多。目标的目标 建议是使用单细胞记录方法研究此功能 猫。猫是一个很好的模型，原因有三个。它的视觉系统 许多尊重的类似于灵长类动物。像人类一样，猫是 基本上是陆地，因此必须解决类似的问题 运动。此外，大量证据表明 CAT的外层皮质（LS）可能会发挥作用 运动过程中的视力主要作用。 基于下一个新颖的视觉显示系统已开发 计算机，以显示模拟视觉的刺激显示 运动期间的场景。显示很大，尺寸约为60度 水平，以充分刺激非常大的“静音” 周围环绕着“ LS中的典型单元格。 将用于询问细胞对移动刺激的反应如何影响 通过将刺激放置在视场的背景下 操纵视频流动电池的不同参数 回答。显示的较小版本，包含高密度的 移动图像将用于询问细胞是否对刺激做出反应 与邻居不同，可能代表障碍或 地形不规则。相同的显示器将用于测试 区域19的响应是一个非常有连接的外部区域 与LS相似，但具有完全不同的响应属性。 假设是区域19对光流仿真的响应将 由于其响应属性不建议任何 在运动过程中的视觉分析中的作用。 LS中大的“沉默环境”的来源，这可能有助于 视野的分析将通过两种方法进行检查。这 由于响应属性，将删除对LS的主要丘脑输入 在此输入中，这可能是宽场效应的可能来源。 然后将测试LS中的响应属性。内在连接 将研究LS内部以查看它们的分布是否可以 在视网膜上解释，或者可能有助于广泛 现场抑制和/或促进。 该项目将填补我们对视觉功能的理解 在单细胞行为的水平上。最终，对 正常的视觉皮质功能将为基础提供洞察力 损害大脑皮层导致的视觉功能障碍的原因。