Functional Architectural of Area V4

V4区功能建筑

• 批准号: 7583769
• 负责人: Daniel Jay Felleman
• 金额: $ 35.14万
• 依托单位: UNIVERSITY OF TEXAS HLTH SCI CTR HOUSTON
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-07-01 至 2011-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7583769
• 关键词: Architecture; Area; Attention; Brain Injuries; Characteristics; Classification; Color; Complex; Contracts; Detection; Development; Electrodes; Exhibits; Goals; Image; Individual; Investigation; Knowledge; Maps; Memory; Methods; Microelectrodes; Neurons; Ocular Prosthesis; Optical Methods; Pattern; Population; Primates; Process; Property; Research; Sampling; Scheme; Shapes; Site; Spatial Distribution; Stimulus; Structure; Sum; Temporal Lobe; Tracer; V4 neuron; Vision; Visual; Visual Cortex; Visually Impaired Persons; area V1; area V4; base; color constancy; extrastriate visual cortex; functional loss; luminance; monocular; novel; object recognition; orientation selectivity; preference; research study; response; vector; visual memory; visual process; visual processing

Area V4 is a key component of primate visual cortex that is involved in many aspects of ‘intermediate’ processing including higher-order shape processing, color constancy, and attention. V4 performs more complex computations than lower areas V1 or V2, but it does not complete object analysis that occurs in the temporal lobe. Despite considerable knowledge about the properties of individual V4 neurons, little is known about how simple and more complex visual features are represented by populations of neurons in V4. Recent experiments indicate that V4 orientation-preferred regions consist of small iso-orientation clusters that systematically shift to form orientation maps. Similarly, V4 color-preferring regions consist of small iso-hue clusters that shift systematically to form pinwheel-, line-, or angle-shaped hue maps. Most importantly, these orientation- and color-preferring maps partially overlap each other, resulting in both color or orientation single-feature modules and color-orientation feature-conjunction modules. In the proposed experiments, intrinsic cortical imaging will determine quantitatively, how preferred color and orientation preference and selectivity are represented in V4 and whether these features are organized into single-feature and feature-conjunction modules. Electrophysiological recording will determine the neuronal bases of these feature maps. Since V4 modules are expected to be small (~0.5-1 mm across), closely spaced microelectrode arrays will optimize the detection of systematic differences in neuronal color and orientation tuning across the cortex. V4 receives dense, largely segregated inputs from V2 thin and interstripes that are thought to convey color and shape information, respectively. However, it remains largely unknown how these inputs contribute to the neuronal properties and functional architecture of V4. In these experiments, distinguishable neuroanatomical tracers will be injected into two or more functionally characterized V4 modules to determine their specific patterns of connections with V2. The long-term goal of this research is to determine how different visual features are represented at different hierarchical levels of visual cortex and to determine how these architectures contributes to object recognition and memory.

区域V4是主要视觉皮层的关键组成部分，它参与了“中间”处理的许多方面，包括高阶形状处理，颜色一致性和注意力。 V4比较低的区域V1或V2执行更复杂的计算，但是它没有完成临时叶片中发生的对象分析。尽管对单个V4神经元的性质有很多知识，但对V4中神经元种群的简单和更复杂的视觉特征的代表知之甚少。最近的实验表明，V4方向偏爱的区域由小的面向ISO的小组组成，这些簇系统地转移到形式的方向图。同样，V4颜色偏爱的区域由小型的ISO-HUE簇组成，这些簇系统会系统地移动以形成风车，线形或角形的色相图。最重要的是，这些方向和颜色偏爱的地图部分相互重叠，从而导致颜色或方向单特征模块以及面向颜色的特征 - 连接模块。在提出的实验中，内在的皮质成像将定量确定，在V4中表示优选的颜色和方向的偏好和选择性如何表示，以及这些特征是否被组织为单特征和特征 - 连接模块。电生理记录将确定这些特征图的神经元基础。由于V4模块的预计将很小（跨越〜0.5-1 mm），因此间距紧密的微电极阵列将优化神经元色中系统差异的检测和跨皮质的方向调节。 V4从V2薄薄层和草皮间接收到密集的，很大程度上隔离的输入，这些输入分别被认为可以传达颜色和形状信息。但是，这些输入如何促进V4的神经元特性和功能架构。在这些实验中，可区分的神经解剖示踪剂将被注入两个或多个功能表征的V4模块，以确定它们与V2连接的特定模式。这项研究的长期目标是确定如何在不同的视觉皮层层次上表示不同的视觉特征，并确定这些体系结构如何促进对象识别和记忆。