Dean's World

Beautiful! Thank you.

Margaret Livingstone at Harvard has done some great perceptual research on why it appears to move. The reason it moves is what is known as the reverse phi phenomenon. The order (Black, Blue, White, Yellow) of the luminance of each color sets up an illusion of motion in your brain. Because the part of our brain that interprets motion is color blind, the luminance information gives the impression of motion across the color boundary, and because the luminance comparison alternates, the reverse phi phenomenon kicks in, and makes the motion appear to be unending. She just spoke about it here at UNC last week. You can see her website here.

Is there something wrong with your reverse phi thingy if it doesn't move? Some guy at work had me look at it and it didn't move for me. I couldn't figure out what he was on about. However, when I see it here at home, looking at it square on, it does move a little but not the whole picture, just on the peripheal. Should I be worried? %-(.