The representation of surface appearance in visual cortex

描述（由申请人提供）：本提案的总体目标是增加对视觉系统如何表示表面特性的理解。特别是，该项目旨在加深我们对感知恒常性的理解，即物体和表面在不断变化的环境中保持其外观的方式。这种研究属于NEI所宣称的理解视觉功能的使命。该提案的第一个目的是研究视觉线索，这对于理解场景如何影响表面亮度的感知很重要。特别是，该目标将使用心理物理学方法来研究视觉系统在恢复表面亮度时用于消除阴影，照明变化和透明度影响的图像特征。第二个目标将建立在第一个目标的基础上；它将寻求识别人类视觉皮层中响应阴影和透明度解释变化的区域，影响感知的表面亮度。第三个目标将研究场景解释对表面和物体大小表示的影响。在这个目标中，我们将研究感知深度如何影响物体的感知大小，以及尺寸恒定机制如何在视觉皮层中表现出来。视觉处理的基本机制在包括精神分裂症和自闭症等精神疾病在内的广泛残疾中受到损害。在许多情况下发现的一个缺陷是环境对视觉处理的异常影响。了解正常的视觉系统是如何处理信息并考虑到环境信息的，可以指导早期诊断这些疾病的测试的发展。

DESCRIPTION (provided by applicant): The broad goals of this proposal are to increase understanding of how surface properties are represented by the visual system. In particular, the project seeks to deepen our understanding of perceptual constancies, the means by which objects and surfaces maintain their appearance in changing contexts. This kind of research falls under the NEI's stated mission of understanding visual function. The first aim of the proposal is to study the visual cues that are important in understanding how scenes affect the perception of surface lightness. In particular, the aim will use psychophysical methods to study the image features that the visual system uses to discount the effects of shadows, illumination changes, and transparency in recovering surface lightness. The second aim will build on the findings of the first; it will seek to identify regions in human visual cortex that respond as the interpretation of shadows and transparencies vary, influencing perceived surface lightness. The third aim will examine the effects of scene interpretation on the representation of the size of surfaces and objects. In this aim, we will study how perceived depth influences the perceived size of objects, and how size constancy mechanisms are represented in visual cortex. PUBLIC HEALTH RELEVANCE Basic mechanisms of visual processing are impaired in a wide range of disabilities including psychiatric conditions such as schizophrenia and autism. One impairment found in a number of conditions is an abnormal effect of context on visual processing. Understanding how the normal visual system processes information and takes into account contextual information may guide development of tests for early diagnosis of such conditions.