A test for mental and physical fatigue.

The illusion was invented by Japanese psychiatrist Akioshi Kitaoka. According to him, "visual illusions" are more helpful than anything else in determining a person's mental state at a given moment. Take a look at the static image above (this is not animation).

If the image is completely still, you have nothing to worry about, your mental health is fine. This result is possible in a person who is balanced, calm and rested.
If the image is moving slowly, you need rest, both physically and mentally. A good night's sleep is especially important, as it is the best antidepressant.
Active image movement is a symptom of accumulated fatigue, high stress levels and declining health. You are in need of rest - maybe even in a treatment facility.

Ps - I have these circles spinning at the speed of light I wonder if anyone else's circles have stopped?