Functional connectivity in primary visual cortex

描述（由申请人提供）：人类大脑需要访问视觉空间的准确地图来解释我们看到的图像。最准确、最完整的视觉地图位于初级视皮层，在那里，所有基本的刺激属性被认为是系统地表示的，包括空间位置、方向和相位。例如，这一页中间的垂直暗条可以在初级视觉皮层中通过其位置（注视点），方向（垂直）和相位（黑暗两侧是光明）来表示。虽然以前的研究在我们理解空间位置和方向如何在初级视觉皮层中映射方面取得了重要进展，但我们仍然不知道空间相位如何在这个地图中表示。鉴于相位在图像处理算法中的重要性，这是一个根本性的知识空白，而图像处理算法经常应用于卫星图像、医学成像、可视电话和字符识别。目前的实验数据表明，空间相位是随机分布在整个皮层;然而，计算模型坚持认为，相位应该聚集在特定区域的皮层地图。我们最近的研究结果表明，第一次，存在明显的集群空间相位密切相关的刺激方向在皮层的映射。此外，我们表明，暗为主的阶段比光为主的更好地代表。本研究项目的主要目标是研究这些新发现的皮质地图的空间相位的组织与一种新的方法，利用多电极记录的最新进展，并具有比过去使用的其他方法更好的时空分辨率。通过我们的多电极方法，我们将揭示空间位置、方向和相位的视觉皮层地图的相互关联的组织，这些地图中的暗优势地形图，以及管理每个100 x 100微米皮层内多个刺激维度的表示的规则。我们将使用这些测量来建立一个详细的数据库的多维映射的刺激功能在视觉皮层地图和测试目前的计算模型的功能皮层架构和皮层的发展。

DESCRIPTION (provided by applicant): The human brain needs to have access to an accurate map of visual space to interpret the images that we see. The most accurate and complete visual map is located in primary visual cortex, where all the basic stimulus properties are thought to be systematically represented, including spatial location, orientation and phase. For example, a vertical dark bar in the middle of this page can be represented in primary visual cortex by its position (point of fixation), orientation (vertical) and phase (dark flanked by light. While previous studies have made important advances in our understanding of how spatial location and orientation are mapped across the primary visual cortex, we still do not know how spatial phase is represented in this map. This is a fundamental gap in knowledge given the importance that phase has in image processing algorithms, which are regularly applied to satellite imagery, medical imaging, videophone and character recognition. Current experimental data suggest that spatial phase is randomly distributed throughout the cortex; however, computational models keep insisting that phase should be clustered in specific regions of the cortical map. Our recent results demonstrate, for the first time, the existence of pronounced clusters for spatial phase that are closely related to the mapping of stimulus orientation in cortex. In addition, we show that dark-dominated phases are better represented than light-dominated ones. The main goal of this research project is to study the organization of these newly discovered cortical maps for spatial phase with a novel approach that takes advantage of recent advances in multielectrode recording and has considerably better spatio-temporal resolution than other methods used in the past. With our multielectrode approach, we will reveal the inter- related organization of visual cortical maps for spatial position, orientation and phase the topography of dark- dominance in these maps and the rules that govern the representation of multiple stimulus dimensions within each 100 x 100 microns of cortex. We will use these measurements to build a detailed database of the multi- dimensional mapping of stimulus features across the visual cortical map and to test current computational models of functional cortical architecture and cortical development.