Courtney S M, Finkel L H, Buchsbaum G
Department of Bioengineering, University of Pennsylvania, Philadelphia 19104.
Vision Res. 1995 Feb;35(3):413-34. doi: 10.1016/0042-6989(94)00132-6.
A biologically-based neural network simulation is used to analyze the contributions to color perception of each of several processing steps in the visual system from the retina to cortical area V4. We consider the effects on color constancy and color induction of adaptation, spectral opponency, non-linearities including saturation and rectification, and spectrally-specific long-range inhibition. This last stage is a novel mechanism based on cells which have been described in V4. The model has been tested with simulations of several well known psychophysical color constancy and color induction experiments. We conclude from these simulations the following: (1) a simple push-pull spectrally specific contrast mechanism, using large surrounds analogous to those found in V4, is very effective in producing general color constancy and color induction behavior; (2) given some spatio-temporal averaging, receptor adaptation can also produce a degree of color constancy; (3) spectrally opponent processes have spatial frequency dependent responses to color and brightness contrast which affect the contribution of the V4 mechanism to color constancy in images with nonuniform backgrounds; and (4) the effect of the V4 mechanism depends on the difference between center and surround while the effect of adaptation depends on the total sum of inputs from both center and surround and therefore the two stages cooperate to increase the range of stimulus conditions under which color constancy can be achieved.
基于生物学的神经网络模拟被用于分析从视网膜到皮层V4区的视觉系统中几个处理步骤对颜色感知的贡献。我们考虑了适应、光谱拮抗、包括饱和度和整流在内的非线性以及光谱特异性长程抑制对颜色恒常性和颜色诱导的影响。最后一个阶段是基于V4区中已被描述的细胞的一种新机制。该模型已通过对几个著名的心理物理学颜色恒常性和颜色诱导实验的模拟进行了测试。我们从这些模拟中得出以下结论：（1）一种简单的推挽式光谱特异性对比机制，使用类似于V4区中发现的大周边区域，在产生一般颜色恒常性和颜色诱导行为方面非常有效；（2）在进行一些时空平均的情况下，感受器适应也能产生一定程度的颜色恒常性；（3）光谱拮抗过程对颜色和亮度对比具有空间频率依赖性响应，这会影响V4机制对具有非均匀背景图像中颜色恒常性的贡献；（4）V4机制的效果取决于中心和周边区域之间的差异，而适应的效果取决于来自中心和周边区域的输入总和，因此这两个阶段相互协作以扩大能够实现颜色恒常性的刺激条件范围。
