颜色恒常性指的是当光源光谱构成或强度发生变化时，人类视觉系统对同一个物体表面的颜色知觉保持不变。本项目旨在通过视觉心理物理学方法和功能性磁共振(fMRI)成像方法针对正常色觉者和异常色觉者探索光源色度对颜色恒常性机制的影响，并在此基础上建立模型。项目首先探索从标准光源变化到彩色光源仅引起红-绿通道信号变化时正常色觉者和异常色觉者从视网膜锥体层到大脑视觉皮层的颜色恒常性机制；然后探索仅引起蓝-黄通道信号变化时的颜色恒常性机制；最后，针对正常色觉者和异常色觉者，建立一般色度光源下，即同时引起红-绿通道和蓝-黄通道信号变化时，视网膜层锥体的适应性和大脑视觉皮层的激活性构成的颜色恒常性机制模型，并通过实验验证模型。本项目对正常色觉者和异常色觉者大脑中的颜色恒常性机制进行深入、系统地研究，为光谱成像系统在不同光源下的颜色再现、遥感探测、目标检测、机器视觉等领域提供了理论基础。

color constancy is a phenomenon where the perceptual color of one surface remains unchanged despite changes of the spectral composition and intensity of illuminants. This project aims to investigate the effect of chromaticity of the illuminant on the color constancy mechanisms of color normal and color deficient people by visual psychophysics and functional magnetic resonance (fMRI) imaging technology and models of color constancy mechanisms were also built. Firstly, the project investigates the color constancy mechanism from the photoreceptoral stage to the higher level visual cortex with illuminant changes from the neutral to chromatic illuminants which only caused changes of red-green opponent channel responses; secondly, the projects investigates that with illuminants changes which only caused changes of blue-yellow opponent channel responses; eventually, color constancy models, which were about the color constancy mechanisms from the photoreceptoral stage to the visual cortex with illuminant changes producing responses changes of both of two chromatic channels, were built for color normal and color deficient people and were verified by experiments. This project investigates deeply and systematically color constancy mechanisms of color normal and color deficient people, which can provide theoretical principles for the research on color reproduction of spectral imaging system under different illuminants conditions, remote sensing, object detection, machine vision and so forth.