CENTRAL AND PERIPHERAL PROCESSES IN VISUAL ADAPTATION

描述(调查人员摘要)：这项研究调查视觉 在复合体中调节颜色和亮度感知的过程 场景。众所周知，物体在自然界中的出现 场景不只依赖于从对象反射的光。一盏灯 在视野的一部分会影响另一种光线的外观。 以前的大多数研究都采用了非常简单的视觉刺激(用于 例如，在彩色适配背景上或在 彩色环绕)，以探索一种光 影响另一个人。虽然这项工作揭示了 在视觉通路上，人们普遍认为对颜色的感知 以及复杂场景中的亮度不能完全用这些来解释 机械装置。 复杂视觉显示器中颜色和亮度的定量研究 很少有人被设计成寻找人类视觉系统的特性。 这些研究中的许多都测量了由于改变 照明光的光谱分布。最新的理论模型 暗示在接受性量子吸收中隐含的信息可能有多大 用来保持(近似)颜色恒定的。然而，这项工作， 很少考虑必须涉及的神经过程。这项研究 这里提出的将分离和定量评估神经过程， 除了简单的色彩适应和对比度机制之外， 复杂视觉刺激的颜色和亮度。 最近来自我的实验室的结果表明，观察到了这样的过程 具有甚至是“略微复杂”的刺激(例如，色调适应背景 在一小段距离外叠加的消色差光 来自测试补丁)。通过在适配场上展示测试灯并 在与测试不相邻的区域中更改另一个灯光时， 在对比度(在边缘)时测量测试的颜色和亮度 测试的结果)保持不变。超越的神经机制的特性 适应性和对比度将通过改变特征(例如， 大小、位置、色度、视网膜照度、均匀性) 不相邻的光。单眼和中枢双眼的视觉机制 将使用单频呈现的刺激来区分通路。 这项研究的一个长期目标是提供敏感和可靠的 有助于眼科疾病诊断的心理物理技术。

DESCRIPTION (Investigator's Abstract): This research investigates visual processes that mediate perception of color and brightness in complex scenes. It is well known that the appearance of an objective in a natural scene does not depend on only the light reflected from the object. A light in one part of the visual field can affect the appearance of another light. Most previous research has employed very simple visual stimuli (for example, a small test patch on a chromatic adapting background or within a chromatic surround) to explore the visual mechanisms by which one light affects another. While this work has revealed fundamental properties of the visual pathway, there is widespread agreement that perception of color and brightness in complex scenes cannot be fully explained by these mechanisms. Quantitative studies of color and brightness in complex visual displays rarely have been designed to seek properties of the human visual system. Many of these studies measured changes in appearance caused by altering the spectral distribution of the illuminating light. Recent theoretical models suggest how information implicit in receptoral quantal absorptions may be exploited to maintain (approximate) color constancy. This work, however, seldom considers the neural processes that must be involved. The research proposed here will isolate and quantitatively assess neural processes, beyond mechanisms of simple chromatic adaptation and contrast, that mediate the color and brightness of complex visual stimuli. Recent results from my laboratory reveal that such processes are observed with even "slightly complex" stimuli (e.g., a chromatic adapting background with a small region of superimposed achromatic light some distance away from the test patch). By presenting a test light on an adapting field and varying another light in a region not adjacent to the test, changes in color and brightness of the test are measured while contrast (at the edge of the test) is held constant. Properties of neural mechanisms beyond adaptation and contrast will be determined by varying the features (e.g., size, location, chromaticity, retinal illuminance, homogeneity) of nonadjacent light. Visual mechanisms in monocular and in central binocular pathways will be distinguished using haploscopically presented stimuli. A long-term goal of this research is to provide sensitive and reliable psychophysical techniques to aid in the diagnosis of eye disorders.