16. The shapes you see when you close your eyes and press on them are called ‘Phosphenes’
They occur when the cells of the retina are stimulated by rubbing or after a forceful sneeze, cough, or blow to the head. The word phosphene comes from the Greek words phōs (light) and phainein (to show). It’s an interesting phenomenon, because it looks like there is light coming in while there isn’t actually any entering your eye.
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