Structural and functional divisions of the primate pulvinar

 描述(申请人提供)：丘脑在大脑功能中的作用一直被忽视，直到最近。尤其是它最突出的组成部分之一--枕骨。这项建议的目标是了解枕骨的功能子部分以及它们如何与不同的视觉皮质区域相关。我们认为，在了解枕骨的作用方面进展如此之少的原因之一是，缺乏关于其属性以及与明确定义的区域的联系的基本信息。在我们最近研究灵长类枕骨的基础上，对枕骨进行功能性解析的关键是 用枕部的视网膜定位图作为起点，就像皮质的视网膜定位图定义皮质的功能区一样。在所有被研究的灵长类动物的下枕和外侧枕中都有两个明确的视网膜定位枕地图。到目前为止，我们对它们的功能以及这两种地图之间的差异仍然知之甚少。我们假设这两个图有偏向地连接到背侧和腹侧流视皮质区。这些偏向应该允许不同的皮质区域以不同的方式使用两个视网膜定位的标记区。我们计划以两个目标的形式来检验这一假设。在目标1中，我们提出了三个解剖学研究，以确定两个枕区映射之间的细胞、轴突和连接的细节，因为这些与皮质视觉区域V1、V2、V3、DL/V4和MT/V5有关。在目标2中，我们提出了三项生理学研究，旨在比较两种视网膜定位图之间的感受野特性及其组织。我们相信，综合起来，这些研究将提供解析灵长类枕骨的关键，进而， 将提供必要的工具来理解枕骨的功能意义，并为丘脑对视觉信息流的控制提供见解。

 DESCRIPTION (provided by applicant): The role of the thalamus in brain function has been somewhat neglected until relatively recently. This is particularly true of one of its most prominen components, the pulvinar. The goal of this proposal is to understand the functional subparts of the pulvinar and how they relate to different visual cortical areas. We argue that one of the reasons there has been so little progress in understanding the role of the pulvinar is that basic information is missing about its properties and connections with well-defined areas. Building on our recent work investigating the primate pulvinar, the key to functionally parsing the pulvinar is to use the retinotopic maps in pulvinar as the starting point just as retinotopic maps in cortex define functional areas in cortex. There are two well-defined retinotopic pulvinar maps that exist in the inferior and lateral pulvinar of all studied primates. To date, we still know very little abut their functions, and the differences between these two maps. We hypothesize that the two maps are biased to connect to dorsal and ventral stream visual cortical areas. These biases should allow separate cortical areas to purpose the two retinotopically defined mapped zones in distinct ways. We plan to test this hypothesis in the form of two aims. In aim 1 we propose three anatomical studies to define the details of the cellular, axonal and connectional differences between the two pulvinar maps as these relate to cortical visual areas V1, V2, V3, DL/V4 and MT/V5. In aim 2 we propose three physiological studies designed to compare the receptive field properties and their organization between the two retinotopically defined maps. We believe, taken together, these studies will provide the keys to parsing the primate pulvinar which, in turn, will provide the necessary tools to understand the functional significance of pulvinar and provide insights into thalamic control of visual information flow.