Can you tell which of these lines is longer? Test them with a ruler or a piece of paper -- you may be surprised.
Close your left eye and stare at the cross. As the circle moves left and right, it should pass through your blind spot and disappear completely! You may need to lean in closer to get this to work.
Move your head around this image. The blue and green color fields will appear to move and change size.
Where does this staircase begin? Where does it end?
Stare at the lobster's eyes long enough, and the dish will seem to repair itself.
Spin Me Round
Although this image is not animated, the tessellated tiles will appear to spin if you stare at them long enough.
Here's another example of the power of contrast. Amazingly, the chess pieces on the top and bottom are the exact same color.
See the pawns against a neutral background.
If you stare at the dot in the center, the colored spots around the edges will fade into the grey background and disappear.
Stare at the moon long enough, and the stars should begin to fade away. How many can you get to disappear?
How many pencils can you see here? What's going on?
As the small circles intersect with the large ones, we seem to see the outlines of a growing and shrinking square. But there is no "square" -- your brain is trying to visualize in terms of solid shapes, and fills in the blanks.
Count how many colors you see here. Most people see four: green, blue, and two shades of a pinkish color.
How many colors are there really?
Pixel Face 1
Can you guess the identity of the faces here? The human brain is remarkable at recognizing extremely low-resolution images.
See a high resolution version of the picture.
Pixel Face 2
Another pixelized face. Can you guess who it is?
Click to see a high-resolution version.
The blue ovals seem to move, but this is a still image.
Stare at the red dot long enough, and the grey stripes will disappear.