Scientists work their magic on ‘shrunken finger illusion’

What happens when you rest a chopped ping pong ball on your finger and look at it from above? Experimental psychologists have shown that our visual system fills in the bottom part of the ball, even though we know it’s missing. This makes our finger feel unusually short, as if to compensate for the ‘complete’ ball. The findings indicate that the completion is due to our visual system, not our imagination.