Do you see these images moving? Swirling just a little bit or perhaps they make you feel a little dizzy? They are not animated gifs but in fact they are still images. That is right, they are actually a static image which is supposed to indicate your level of stress.

These images are currently doing the email rounds and the story goes that these patterns are used to test the level of stress a person can cope with. The more movement you perceive the less stress you can handle. The slower the pictures move, the better your ability of handling stress.

I actually think they are just an optical illusion rather than a “stress test” but I could be wrong.
I was googling to see if I could find the source and copyright of these images. I was not successful but I did turn find some interesting sites on optical illusions however.
76 Optical Illusions and Visual Phenomena by Michael Bach will not only trick your eye but make you question what you actually do see. The tour is very interesting and worth taking time out to explore.
There are many optical illusions and this site has explained 120 of them and Optical Illusions and Pictures is an archive of optical illusions
The Visual Fun House of optical illusions is a blog which solicits images from readers and collates together a collection of images that trick the eye.