What happens in the body and brain when someone goes unconscious from a head injury?

Question

For a period of time longer than usual passing out, and shorter then a coma.

In: Biology

Answer 1

Being knocked out from a blow to the head comes from pressure on the brain stem (which provides blood for the brain). When enough pressure is applied in a certain way, the brain stem “kinks” for a bit, and shuts off both hemispheres because there’s no blood flow. Probably nothing happens in your brain.

However, the brain stem also connects your nerves and brain. Sometimes when a person is knocked unconscious you’ll see hands become curled or a “fencing response”. This can happen when that pressure on the brain stem also causes disruption to the nervous system.

In the cases you are talking about, the brain stem basically just unkinks itself and you regain consciousness