CENTRAL AND PERIPHERAL PROCESSES IN VISUAL ADAPTATION

描述：（来自主要研究者摘要）颜色感知 取决于眼睛和大脑的神经过程。 颜色和亮度 单个孤立的光与光的物理性质密切相关。 特性，但是相同的光可以被感知为具有非常 不同的颜色和亮度外观时，作为一个复杂的一部分， 现场 视觉中一个基本的未解决的问题是颜色和 光的亮度外观取决于其他刺激的背景， 风景 虽然以前的研究已经考虑过这个问题，但大多数研究 使用非常简单的视觉刺激，例如叠加在 均匀的背景或在均匀的周围场中。 这项工作 揭示了影响颜色感知的基本机制，但没有考虑 重要的神经过程依赖于视觉刺激， 比统一的背景或环境复杂。 近年来研究表明 颜色感知强烈依赖于即使是稀疏的代表 在一个适度复杂的，不均匀的视觉刺激的色度。 拟议的研究将评估颜色的基本属性， 复杂场景中的亮度感知，通过测试特定假设 关于神经机制的空间，时间和色彩特征。 这些神经机制的生理轨迹也将是 研究了 这将通过进行心理物理测量来实现 色彩感知与许多不同类型的精心设计的 非均匀场 增量和减量的出现将 为了研究全方位的颜色感知， 发生在自然场景中。 总的来说，这项研究将研究神经过程 在更接近自然观察的条件下调节颜色外观 比之前的大多数研究都要多 色觉减退， 患者通常通过颜色匹配测试进行评估， 使用非常简单的字段的歧视。 只影响神经机制 由更复杂的领域，如发生在自然观察，不进行评估。 一 这项研究的长期目标是全面了解神经过程 调节任意复杂视觉的颜色和亮度感知 刺激，并开发测试来评估这些神经系统的功能， 机制

DESCRIPTION: (from principal investigator's abstract) Perception of color depends on neural processes of eye and brain. The color and brightness of a single, isolated light are closely related to the light s physical characteristics, but the same light may be perceived to have a very different color and brightness appearance when viewed as part of a complex scene. A fundamental unsolved problem in vision is how the color and brightness appearance of a light depend on the context of other stimuli in view. While previous research has considered this problem, most studies have used very simple visual stimuli such as a test field superimposed upon a uniform background or within a uniform surrounding field. This work has revealed basic mechanisms affecting color perception but does not consider important neural processes that depend on visual stimulation that is more complex than a uniform background or surround. Recent studies show that color perception depends strongly on even sparsely represented chromaticities within a modestly complex, inhomogeneous visual stimulus. The proposed research will evaluate fundamental properties of color and brightness perception in complex scenes, by testing specific hypotheses concerning neural mechanism spatial, temporal and chromatic characteristics. The physiological locus of these neural mechanisms also will be investigated. This will be achieved by making psychophysical measurements of color perception with many different types of carefully designed inhomogeneous fields. The appearance of both increments and decrements will be studied in order to investigate the full range of color percepts that occur in natural scenes. Overall, this research will study neural processes that mediate color appearance under conditions closer to natural viewing than have been studied in most previous research. Reduced color vision in patients is typically assessed with tests of color matching or discrimination that use very simple fields. Neural mechanisms affected only by more complex fields, as occur in natural viewing, are not evaluated. A long-term goal of this research is to understand fully the neural processes mediating color and brightness perception of arbitrarily complex visual stimuli, and to develop tests to assess functioning of these neural mechanism.