Shevell S K, Wei J
Departments of Psychology and Ophthalmology and Visual Science, University of Chicago, 939 East 57th St., 60637, Chicago, IL, USA.
Vision Res. 2000;40(23):3173-80. doi: 10.1016/s0042-6989(00)00167-x.
The color appearance of a light can be altered by introducing a second, surrounding field. This phenomenon, called chromatic induction, is attenuated by chromatic variation within a remote region outside the surround [Shevell & Wei (1998). Vision Research, 38, 1561-1566]. We now consider the locus of the neural mechanism mediating the attenuation caused by the remote chromatic contrast. In the first experiment, the magnitude of chromatic variation within the remote region is changed either: (i) in the same eye that views the patch judged in color; or (ii) in only the opposite eye. The measurements are virtually the same in both cases, which implies attenuation of chromatic induction is mediated by a central, binocular mechanism. In the second experiment, the patch with its immediate inducing surround is changed in binocular disparity relative to the remote region with chromatic variation. The patch and surround, seen together in one depth plane, are perceived to be in front of, behind, or in the same plane as the remote region with chromatic variation. Attenuation of chromatic induction is strongest when the patch and surround are in the same depth plane as the remote region. This change of color appearance with disparity is consistent with a central binocular process. Overall, the color-appearance measurements are explained by monocular encoding of chromatic differences at edges, and a central binocular mechanism of chromatic-contrast gain control.
通过引入第二个环绕区域，可以改变光的颜色外观。这种现象称为色诱导，它会因环绕区域之外远处区域的颜色变化而减弱[谢韦尔和魏（1998年）。《视觉研究》，38卷，1561 - 1566页]。我们现在考虑介导由远处颜色对比度引起的减弱的神经机制的位点。在第一个实验中，远处区域内颜色变化的幅度以以下两种方式之一改变：（i）在观察颜色判断斑块的同一只眼睛中；或（ii）仅在对侧眼睛中。两种情况下的测量结果几乎相同，这意味着色诱导的减弱是由一种中枢性的双眼机制介导的。在第二个实验中，带有其直接诱导环绕区域的斑块相对于具有颜色变化的远处区域在双眼视差上发生改变。在一个深度平面中一起看到的斑块和环绕区域被感知为在具有颜色变化的远处区域的前方、后方或同一平面内。当斑块和环绕区域与远处区域处于同一深度平面时，色诱导的减弱最强。这种颜色外观随视差的变化与中枢性双眼过程一致。总体而言，颜色外观测量结果可以通过边缘处颜色差异的单眼编码以及颜色对比度增益控制的中枢性双眼机制来解释。
