Negative After images:
It is when the image is inverted after staring at an image for a long time.
It all happens when your photoreceptor cells in the retina, primarily the cone cells, become overstimulated and fatigued which makes them lose their sensitivity. This leaves the brain to produce the negative afterimage (the inverted version of something).
The negative afterimage is always complementary to the color you were staring at. (for example, staring at a cyan and black american flag and then looking at a blank wall, it would look like the american flag!)
For example, red is complementary to cyan and blue is complementary to yellow.
You don’t notice this in everyday life because the tiny movements in your eyes prevent your eyes from being overstimulated. But when you stare at a negative after image for a long time, you are preventing these movements which make them fatigued.
Sources used:
https://www.verywellmind.com/the-negative-photo-illusion-4111086
https://www.illusionsindex.org/i/negative-afterimages
Credits to Tobu for the music. Tobu - Cloud 9
Track: Itro & Tobu - Cloud 9
Music provided by Tobu & Itro.
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