This classic illusion only works after you turn away from the image, and creates a ghost of the image. Try staring at the dot in the centre of the flag for 30 seconds. Then turn away and face a white background (a wall, ceiling, or even a blank word document). Can you see the red, white and blue American flag?
The eyes see the image and its intense colours and are stimulated for a period of time by these colours, while the brain is relating this to an unconscious reference (the red, white and blue flag), to solve the puzzle.
The Red, White, and Blue...
Stare at the center of the weird flag for about 1 minute.
Don't move your eyes. Then look at an empty white sheet
of paper, and you'll see the red, white, and blue flag.
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