Interesting fact:

This image is an exact negative replica of the U.S.A.’s flag. By staring at it and then closing your eyes, you experience something known as a ‘negative afterimage’. This occurs when the photoreceptors in your eyes – primarily the cone cells – become fatigued due to overstimulation. This results in a loss of sensitivity in these particular cells, while the surrounding photoreceptors remain fresh. Once you close your eyes, these cells create a reaction that almost inverts the negative image, making it seem like you’re looking at the original colors. Remarkable!