The display below is an interactive demonstration of apparent
By clicking on the buttons you can change this display
in countless ways. Each click on the SLOW button makes the dots stay
on a little longer. Each click on the FAST button makes the dots
stay on a little shorter. The ISI_PLUS increases the time between the appearance
of dots. The ISI_MINUS decreases the time between the appearance
of dots. The BIG button makes dots bigger, and the SMALL button makes
dots smaller. The CLOSE_V button brings the dots closer vertically,
and the FAR_V button moves them farther away vertically. The CLOSE_H
button brings the dots closer horizontally, and the FAR_H button moves
them farther away horizontally.The COLOR button randomly changes the colors
of the dots. The RESET button gives back the original display.
You can now experiment and see for yourself how your perception changes
as you click on these buttons. Notice that this display is bistable:
You can see the dots moving up and down, or side to side. As you
move the dots closer together horizontally, you will be more biased to
see the dots move side to side. As you move the dots closer together
vertically, you will be more biased to see the dots move up and down.
To find out more about how you see this illusion and other illusions, see
Intelligence, by Donald D. Hoffman.