Do the rectangles inside the circle seem to be moving?   Do the circles seem to spin?   Doesn't it look like cylinders are rotating?   What do the dots seem to do as you look at this picture?   Are the horizontal lines parallel or do they slope?   Move back and forth while looking at the image.

How many things can you find hidden in the Mona Lisa?   How many deer do you see in this picture?   What do you see in this picture? An old witch? Or a pretty young girl?   1. Stare at the white dot for 30 seconds. 2. Look at a light colored surface. 3. Who do you see?   How many legs does this elephant have?