Why Do Shapes Appear When You Blink?

Blinking can make you see shapes because your eyes change focus really fast. When you blink, sometimes the light that enters your eye gets a little jumbled, and your brain tries to make sense of it. That's why you might see squiggly lines or colors when you open your eyes again.

It’s like looking at a blurry picture, then all of a sudden it becomes clear, and your brain fills in the blanks with shapes that aren’t really there.