The yellow arrows on the purple background below appear to move independently to the left and the right. Specifically, the top and bottom rows of arrows seem to have the most significant amount of motion for me. If you are having trouble getting this static image to move, try staring at it while moving your eyes around to look at different parts of the image. This eye movement should induce the sensation of motion and cause the arrows to begin to slide from side to side. Akiyoshi Kitaoka, a professor of Psychology at Ritsumeikan University in Kyoto, Japan, designed this optical illusion.