This age-old illusion, first documented by Aristotle, is called the Motion Aftereffect by today’s scientists. Why does it happen, though? Is it because we are consciously aware that the background is moving in one direction, causing our brains to shift their frame of reference so that we can ignore this motion? Or is it an automatic, subconscious response?
Davis Glasser, a doctoral student in the University of Rochester’s Department of Brain and Cognitive Sciences thinks he has found the answer. In their paper, the scientists show that humans experience the Motion Aftereffect even if the motion that they see in the background is so brief that they can’t even tell whether it is heading to the right or the left.
Find more here Neuroscientists find famous optical illusion surprisingly potent.
Interestingly, we found the affect still worked after watching the video and then looking at a page of text on a piece of paper or a web site – Optical Spy