Motion Induced Blindness
Stare at the blinking green dot in the center of this animated image. As you do, you will begin to experience a motion induced blindness. The three yellow dots will start to randomly disappear and reappear. Sometimes you will notice that one is missing and other times it may seem that two or all three are missing. The yellow dots do not disappear at all, they are always present. This can be confirmed by watching the animation for a while without fixating on the blinking green dot.