The human eye is a pretty incredible thing. We can not only see colors and shapes but also give everything we see meaning and definition, thanks to the eye’s connection to the brain. While our eyes aren’t quite as sensitive as some others in the animal kingdom, they’re quite adept at working both in daylight and the dark of night, and are quite good at detecting motion.
Still, there are limitations. Stare at something too long, and it takes a while for our eyes to “forget” what they’ve seen. The rods and cones that sense various colors of light began to get overwhelmed, and our brain tries to compensate. The result is this bizarre illusion that can turn a black and white image into a full-color one, just by staring for a bit.