The neural representation and transformation of color in human visual cortex

人类视觉皮层颜色的神经表征和转换

• 批准号: 8461563
• 负责人: DAVID J HEEGER
• 金额: $ 36.58万
• 依托单位: NEW YORK UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-05-01 至 2015-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8461563
• 关键词: 3-Dimensional; Amblyopia; Appearance; Area; Behavioral; Biological Models; Brain; Cognitive; Color; Color Perception; Complex; Computer Simulation; Data Analyses; Dependence; Discrimination; Elements; Face; Functional Magnetic Resonance Imaging; Human; Illusions; Linear Regressions; Measurement; Measures; Methods; Modality; Modeling; Motion; Motor; Movement; Nature; Neurons; Pattern; Population; Positioning Attribute; Principal Component Analysis; Process; Protocols documentation; Psychophysics; Research; Retinal; Retinal Cone; Retinal Diseases; Sensory; Series; Signal Transduction; Staging; Stimulus; Sum; Techniques; Testing; Translations; Visual; Visual Agnosias; Visual Cortex; Visual Illusions; Visual Perception; Visual impairment; Visual system structure; Weight; Work; base; color category; experience; extrastriate visual cortex; insight; neural patterning; novel; object recognition; relating to nervous system; research study; response; restoration; sensory stimulus; vector; visual information

DESCRIPTION (provided by applicant): The representation of any stimulus can be seen as a unique and distributed pattern of activity in a large population of neurons. These neural representations are thought to undergo a series of transformations across processing stages in visual cortex, and to depend on behavioral demands. The nature of these transformations reveals important insights into the computational mechanisms underlying the formation of behaviorally meaningful neural representations from incoming sensory signals. In this proposal, the focus is on measuring the neural representations and characterizing the transformations for a specific visual modality: color. The representation of color takes on many different forms. For example, humans discriminate between many thousands of hues but use only a handful of discrete color categories. This makes color an ideal candidate to investigate distributed neural representations. The novel empirical and theoretical approaches in the current proposal aim to significantly advance understanding of 1) how the human visual system represents color, 2) how this distributed neural representation is transformed across the hierarchy of visual cortical areas 3) the dependence of these representations on behavioral demands, and 4) the dependence on context. Aim 1 experiments will test the hypothesis that the neural representation of color is transformed as chromatic signals ascend the visual system. Neural color spaces will be derived from functional magnetic resonance imaging (fMRI) measurements, using novel experimental protocols and multivariate data analysis techniques. These neural color spaces will be compared with perceptual color spaces derived from psychophysical measurements of color discrimination and categorization. Aim 1 experiments will also test the hypothesis that neural representations of color depend on behavioral demands. The proposed experiments will distinguish between two specific computational hypotheses: 1) that neural color spaces change for different behavioral tasks, indicating a change in the underlying selectivity and tuning of the neurons, versus 2) a (possibly selective) increase in response gain, with no evidence for a change in the color space. Aim 2 experiments will test the hypothesize that changes in color perception, due to a dramatic visual illusion, are correlated with corresponding shifts in the underlying neural representation, and that the extent of the shift in the neural representation varies between visual areas, depending on the neural color space in each visual area. Ultimately, color provides a model for more complex neural representations (e.g., those underlying face and object recognition, control of movement, etc.) and the findings will provide general insights about distributed neural processes and representations. Consequently, the proposed research will provide information about how the brain transforms an incoming set of signals (of any modality) into a set of meaningful representations that subserve a multitude of tasks.

描述（由申请人提供）：任何刺激的表征都可以被视为大量神经元中独特和分布的活动模式。这些神经表征被认为在视觉皮层的处理阶段经历了一系列的转换，并依赖于行为需求。这些转换的本质揭示了从传入的感觉信号形成具有行为意义的神经表征的计算机制的重要见解。在这个建议中，重点是测量神经表征和表征特定视觉形态的转换：颜色。颜色的表现有许多不同的形式。例如，人类可以区分数千种颜色，但只使用少数几种独立的颜色类别。这使得颜色成为研究分布式神经表征的理想候选者。本文提出的新的经验和理论方法旨在显著推进以下方面的理解：1)人类视觉系统如何表征颜色；2)这种分布式神经表征如何在视觉皮层区域的层次中转换；3)这些表征对行为需求的依赖性；4)对环境的依赖性。目的1实验将检验颜色的神经表征被转换为颜色信号上升的视觉系统的假设。神经色彩空间将从功能磁共振成像（fMRI）测量中获得，使用新的实验方案和多变量数据分析技术。这些神经色彩空间将与来自色彩辨别和分类的心理物理测量的感性色彩空间进行比较。目的1的实验也将测试颜色的神经表征依赖于行为需求的假设。提出的实验将区分两种特定的计算假设：1)神经颜色空间因不同的行为任务而改变，表明潜在的选择性和调谐的变化