“Optical illusions fool us by violating our assumptions about what we see. The end results of how our brains process visual cues can be fascinating at times. Here’s a somewhat simple, but extremely effective illusion, that exemplifies just that. Processing objects based on their surroundings is the match that lights the fire for this illusion. Small paper ovals, when placed in front of a moving paper background, will appear to change shape and undulate right in front of your eyes!