#optisk synvilla

»Look closely at the image abowe and take a mental snapshot. In a few moments, it'll be gone.  No, seriously. Stare at the center of this image. For the first few seconds you'll feel kind of dumb, and then about 10 to 20 seconds the colors should just... disappear. It's wild.   This works because of a principle called Troxler Fading, which makes shapes and colors in the periphery of your vision change hue and fade over time.«