Columnar Organization of Surface vs. Border Information in Human Areas V2 and V3

人类区域 V2 和 V3 中表面与边界信息的柱状组织

• 批准号: 9346107
• 负责人: ROGER B TOOTELL
• 金额: $ 44.42万
• 依托单位: MASSACHUSETTS GENERAL HOSPITAL
• 依托单位国家: 美国
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-09-30 至 2019-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9346107
• 关键词: Affect; Amblyopia; Animals; Architecture; Brain; Brain Diseases; Cerebral cortex; Clinical; Color; Color Visions; Cortical Column; Crowding; Data; Depth Perception; Disease; Eye; Functional Magnetic Resonance Imaging; Geometry; Human; Image; Imaging Techniques; Length; Link; Location; Maps; Measurement; Measures; Meridians; Motion; Nature; Neurons; Pattern; Perception; Population; Process; Property; Publishing; Radial; Reporting; Research; Resolution; Role; Stimulus; Stream; Surface; Surface Properties; Syndrome; System; Testing; Textbooks; Texture; Thick; Thinness; Variant; Vision; Vision Disparity; Visual; Visual Cortex; Visual Fields; Work; area V2; area V3; area striata; base; cortex mapping; extrastriate visual cortex; imaging approach; information processing; luminance; neuron component; nonhuman primate; receptive field; response; retinotopic; segregation; stereoscopic; visual information; visual map; visual stimulus

Project Summary/Abstract More than a third of human cerebral cortex responds to visual information, which enters cortex through primary visual cortex (V1). Accordingly, much is known about V1 processing. However, much less is known about information processing in the `next' cortical area (V2), and even less is known about higher area V3. In animal studies of V2, one key to understanding information processing is that different types of stimulus features are processed ~independently in segregated `stripes' of cortical columns. One set of columnar stripes responds selectively to variations in color, a surface property. Another set of columns responds best to variations in boundaries based on stereoscopic (`3D') stimuli (thus the latter research can clarify mechanisms underlying amblyopia). Study of such columns can reveal fundamental responses in the component neurons. Previously, it has been unknown whether such functional stripes/columns exist in humans. Conventional functional magnetic resonance imaging (fMRI) techniques cannot spatially resolve such columns, which are quite small. By using a specialized fMRI approach (7T, 1 mm3), here we successfully demonstrated (and have begun analyzing) such columns and stripes in human areas V2 and V3. Beyond simply imaging such columns, we propose to test a new hypothesis: early visual cortex processes boundaries vs. surface features, in two parallel streams, within thin and thick stripes (respectively) in V2. We also test whether that surface-vs.- boundary information is then passed forward to segregated columns in V3. If confirmed, this hypothesis will clarify (and help unify) the diverse existing data about the nature of functional processing in early visual cortex. Aim 1 will test our hypothesis by presenting different types of stimulus boundaries or surface properties, testing for correspondingly higher responses in thick or thin stripes, respectively. Each of five sub-aims will isolate and test responses to boundaries defined by differences in either: binocular disparity (sub-aim 1.1), or direction of motion (1.2), texture (1.3), color (1.4), or luminance (1.5). Aim 2 tests the conclusions from Aim 1 in a complementary way, by presenting stimuli that include only a single boundary, in each quadrant of the visual field, and in the corresponding cortical map. Aims 3.1 and 3.2 will test for higher activity in retinotopically-predicted subregions in thick stripes (and related V3 columns) due to inferred or illusory contours. The stimulus used in aim 3.3 predicts a shift in activity between the thin vs. thick stripe systems, produced by retinotopically specific colored surfaces- vs. boundaries, respectively. Different points in visual space (either surfaces or boundaries) are mapped onto the cortical surface, a property known as `retinotopic' mapping. Thus the columns (aim 1) co-exist with maps of retinotopy. However It is not known how these two maps accommodate each other at the spatial resolution of columns. Aim 3 will clarify whether thin vs. thick stripes (and related V3 columns) have duplicated retinotopic maps (sub-aim 3.1), or specific retinotopic `gaps' (3.2), or smaller vs. greater retinotopic spread, respectively.

项目总结/摘要 超过三分之一的人类大脑皮层对视觉信息做出反应，这些信息通过 初级视皮层（V1）。因此，对V1处理有很多了解。然而， 关于“下一个”皮层区域（V2）的信息处理，对更高区域V3的了解更少。在 V2的动物研究，理解信息处理的一个关键是不同类型的刺激， 特征在皮层列的隔离“条纹”中独立地被处理。一组柱状条纹 对颜色的变化有选择性的反应，这是一种表面特性。另一组列最好响应于 基于立体（“3D”）刺激的边界变化（因此后一研究可以阐明机制 潜在弱视）。对这种列的研究可以揭示组成神经元的基本反应。 以前，人们不知道这种功能性条纹/柱是否存在于人类中。常规 功能性磁共振成像（fMRI）技术不能在空间上分辨这样的柱， 很小。通过使用专门的fMRI方法（7 T，1 mm 3），在这里我们成功地证明了（并已 开始分析）人类区域V2和V3中的这些列和条纹。除了简单地对这些柱成像之外， 我们提出测试一个新的假设：早期视觉皮层处理边界与表面特征，在两个 平行流，分别在V2中的薄条纹和厚条纹内。我们还测试了表面与表面之间的关系。 然后将边界信息向前传递到V3中的隔离列。如果得到证实，这一假设将 澄清（并帮助统一）有关早期视觉皮质功能处理性质的各种现有数据。 目标1将通过呈现不同类型的刺激边界或表面特性来测试我们的假设， 分别测试厚或薄条纹中相应较高的响应。五个次级目标中的每一个都将 隔离和测试对由以下差异定义的边界的反应：双眼视差（子目标1.1），或 运动方向（1.2）、纹理（1.3）、颜色（1.4）或亮度（1.5）。 目标2以一种补充的方式测试目标1的结论，通过呈现只包括一个 单个边界，在视野的每个象限，并在相应的皮质地图。目标3.1和3.2 将在厚条纹（和相关V3列）中的视网膜定位预测子区域中测试更高的活性， 推断或虚幻的轮廓。目标3.3中使用的刺激预测了瘦与瘦之间的活动变化。 厚条纹系统，分别由视网膜特定的彩色表面与边界产生。 视觉空间中的不同点（表面或边界）映射到皮质表面， 称为“视网膜位置”映射的特性。因此，列（目标1）与视网膜病变图共存。然而 目前还不知道这两个地图如何在列的空间分辨率相互适应。目标3将 澄清薄条纹与厚条纹（以及相关V3列）是否具有重复的视网膜定位图（子目标3.1）， 或特定的视网膜定位“间隙”（3.2），或较小的视网膜定位扩散对较大的视网膜定位扩散。