Central and Peripheral Processes in Visual Adaptation

描述（由申请人提供）：本研究的目的是了解在自然观看中调节颜色和亮度感知的神经通路。颜色和亮度的匹配、辨别和外观已经在简单的视野中进行了广泛的研究，但对于自然观看中典型的复杂、动态场景中物体的颜色感知知之甚少。简单的字段可能会严重低估上下文对颜色和亮度的影响。即使是颜色恒常性的研究也主要关注光照变化下的颜色感知。相比之下，这里的每条研究都侧重于随空间和/或时间变化的复杂环境中的色彩感知。有五个研究方向，每个方向都旨在揭示调节复杂场景感知的视觉基本原理。第一个测试用不均匀的彩色背景图案测试颜色感知的神经表征。目的是了解任何空间色彩图案的色彩感知。第二个研究研究视网膜分离区域的整合，所有这些区域都受到单个物体的刺激。分离的区域是由前景中的其他对象部分遮挡造成的。感知分组整合了分离的区域，因此人们看到的是单个物体，但分组也会影响颜色感知。第三条研究考察了颜色与形式的感知结合。物体具有许多属性，例如形状、深度、运动方向和颜色。为了感知统一的对象，属性必须被整合。这项研究使用了一种最近发现的新颖范式，该范式给出了颜色绑定中明显且持续的错误。利用该范式来测试将颜色与形式结合的替代理论。第四行工作检查随时间变化的背景光。正如经典研究中那样，简单的时间变化背景无法解释实验室外可能发生的更复杂的时间模式的影响。其原因是神经非线性，本研究将对其进行表征。第五组实验测试了非常长期的色彩适应（数天或数周）的替代理论，这反映了自然观看中隐含的神经可塑性。许多天内颜色外观的逐渐变化揭示了对色彩环境的适应。每条研究都调查颜色和亮度感知的基本神经过程，目前的临床测试既没有很好地理解也没有评估这些过程。许多潜在的神经过程都是皮质的。对复杂场景中的整体物体的感知是正常视觉的一个基本方面。这项研究为诊断程序提供了重要的基础，可以揭示以前未识别的视觉处理缺陷。颜色和亮度的心理物理学测量将测试替代理论。定量建模将结合生理学研究中视觉通路的特征。

DESCRIPTION (provided by applicant): The aim of this research is to understand neural pathways that mediate color and brightness perception in natural viewing. Matching, discrimination and appearance of color and brightness have been studied extensively with simple visual fields but little is known about the color perception of objects within complex, dynamic scenes typical of natural viewing. Simple fields can severely underestimate the influence of context on color and brightness. Even studies of color constancy are concerned mainly with color perception under changes of illumination. By comparison, each line of research here focuses on color perception within a complex context that varies over space and/or time. There are five lines of research, each chosen to reveal fundamental principles of vision that mediate perception of complex scenes. The first tests neural representations for color perception with inhomogeneous chromatic background patterns. The aim is to understand color perception with any spatiochromatic pattern. The second investigates integration of retinally separated regions, all of which are stimulated by a single object. The separated regions result from partial occlusion by other objects in the foreground. Perceptual grouping integrates the separated regions so one sees a single object but grouping also affects color perception. The third line of research examines perceptual binding of color to form. An object has many attributes such as shape, depth, direction of motion and color. The attributes must be integrated for the percept of a unified object. This research uses a novel, recently discovered paradigm that gives clear and sustained errors in color binding. The paradigm is leveraged to test alternative theories of binding color to form. The fourth line of work examines temporally varying background light. Simple temporally varying context, as in classical studies, fails to explain the influence of more complex temporal patterns that can occur outside the laboratory. The cause is a neural nonlinearity, which will be characterized by this study. The fifth set of experiments tests alternative theories of very-long-term chromatic adaptation (over days or weeks), which reflects neural plasticity implicit in natural viewing. Gradual changes in color appearance over many days reveal adaptation to the chromatic environment. Each line of research investigates basic neural processes of color and brightness perception that are neither well understood nor assessed by current clinical tests. Many of the underlying neural processes are cortical. Perception of integrated objects within complex scenes is a fundamental aspect of normal vision. This research provides essential underpinnings for diagnostic procedures that can reveal previously unidentified deficits in visual processing. Psychophysical measurements of color and brightness will test alternative theories. Quantitative modeling will incorporate characteristics of visual pathways from physiological studies.