Look at this image for 30 seconds, then look at a white surface (paper, wall, etc.) and blink really quick.
You should have seen the image in color. Why? Well, it's called a negative afterimage. It occurs because the brain, and the retina in the eye process the negative image. Its an adaptation of photo receptors in the retina. Fixating one's eyes on one spot (in this case, the red dot) reduces the micro saccades that we usually use to see everything. These micro saccades let us see these everyday things without keeping those images constantly on our mind(by keeping the image attached to a group of photo receptors). When we transfer our vision from the image to the blank/white space, photo receptors that get accustomed to the image, don't signify effectively anymore, but the photo receptors (surrounding adapted photo receptors) signal opponent cells in the lateral geniculate nucleus (LGN) that are involved in color vision. I believe that the 3 colored dots on the nose, stimulate the color receptors in the retina, and it reflects the negative image, letting your eyes see it in color.
http://webvision.med.utah.edu/2012/06/your-brain-develops-the-negative/
