CENTRAL AND PERIPHERAL PROCESSES IN VISUAL ADAPTATION

视觉适应的中枢和外围过程

• 批准号: 3259347
• 负责人: STEVEN K SHEVELL
• 金额: $ 17.52万
• 依托单位: UNIVERSITY OF CHICAGO
• 依托单位国家: 美国
• 财政年份: 1983
• 资助国家: 美国
• 起止时间: 1983-09-01 至 1996-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3259347
• 关键词: binocular vision; brightness discrimination; color visions; human subject; light adaptations; light intensity; neural information processing; psychophysics; visible light; vision tests; visual fields; visual pathways; visual perception; visual photoreceptor; visual stimulus

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.

描述（研究者摘要）：本研究调查视觉 调节复杂的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 场景不仅仅依赖于从物体反射的光。 光 在视野的一部分可以影响另一个光的外观。 大多数以前的研究都采用非常简单的视觉刺激（对于 例如，在彩色适应背景上或在 彩色环绕），以探索视觉机制， 影响另一个。 虽然这项工作揭示了 在视觉通路中，人们普遍认为， 复杂场景中的亮度不能完全用这些来解释 机制等 复杂视觉显示中颜色和亮度的定量研究 很少被设计成寻求人类视觉系统的特性。 这些研究中有许多测量了改变皮肤的颜色所引起的外观变化。 照明光的光谱分布。 最新理论模型 暗示了感受器量子反射中隐含的信息可能 用于保持（近似）颜色恒定性。 然而，这项工作， 很少考虑必须涉及的神经过程。 研究 这里提出的将隔离和定量评估神经过程， 超越了简单的色彩适应和对比机制， 复杂视觉刺激的颜色和亮度。 我的实验室最近的结果表明， 即使是“稍微复杂”的刺激（例如，彩色背景 在一定距离外有一小块消色差叠加光 从测试补丁）。 通过在适应场上呈现测试光， 在不邻近测试的区域中改变另一个光， 测试的颜色和亮度被测量，而对比度（在边缘处 测试）保持不变。 神经机制的特性 将通过改变特征（例如， 尺寸、位置、色度、视网膜照度、均匀性） 非相邻光 单眼和中央双眼的视觉机制 将使用单倍镜呈现的刺激来区分通路。 这项研究的一个长期目标是提供灵敏可靠的 心理物理技术，以帮助诊断眼疾。