Video: Contrast colour
If you can stare at this rotating circle without going into a seizure, you should see three concentric circles: pink, blue and green. But when the circle stops moving, you can see that the arcs that create these circles are actually all black.
Even though we can't consciously differentiate the colours of the individual segments when they're moving quickly, our brains can nonetheless pick them up.
That's why each concentric circle appears as the complementary (loosely speaking, the "opposite") colour of the segment that it's in.
The illusion was created by Haruaki Fukuda and Kazuhiro Ueda of the University of Tokyo, Japan.
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