optical-illusion

This hinted at something that no one had ever suspected -- that the brain tracks moving things more easily that still things. We have a built-in bias toward detecting action. Why? Because it's probably more critical for animals to spot moving things (predators, prey, falling trees) than static things, which can wait. In fact, our vision is so biased toward movement that we don't technically see stationary objects at all. To see something stationary, our brains have to scribble our eyes subtly over its surface. Experiments have even proven that if you artificially stabilize an image on the retina with a combination of special contact lenses and microelectronics, the image will vanish.