Why do we see a "flash" when we hit our head really hard?

Question

Just curious. It's been bugging me because when I was little I was riding my bike and I fell. I smashed my head on the concrete and saw a bug flash. Other people also talk about seeing flashes when hitting their head.

Why?

Answer 1

YOU NEED TO GO EMERNGY ROOM HAVE A DOCTOR HAVE E-RAY FOR HEAD  GO NOW GET ODD COMPUTER HAVE YOUR MOM YOUR DAD TAKE YOU GO NOW????????

Answer 2

your brain functions on small amounts of electricty signals and when you hit your head to hard your brain hits your skull or moves to fast and for a  split split second nocks the signal around and disrupts it

Answer 3

its called a migraine

Answer 4

I believe it is because the brain is jolted which can cause misfires in certain nerves. Like when the doc taps the nerves in your knee and your leg involuntarily kicks. These misfired nerves affect many things including balance sensors in the inner ear, and stomach control, which is why some people are dizzy or sick right after banging their head.

In the case of the eyes, the brain interprets the misfires in the optical pathways as bright coloured lights or flashes.

Hope this answers your question.