Look into the research done with heads decapitated using a Guillotine. It is pretty interesting. They discovered that the human head remained conscious for a short time after separation from the body and there were experiments with sending oxygenated blood to the brain and temporarily ‘reviving’ the deceased heads. There are reported cases of the heads moving and having the ability to form expressions a few minuets after death.
A bit morbid, I know, but the studies were done way back when and the fact that they were able to preform such advanced studies with such primitive technologies is amazing.
Check out the Book : Stiff its about human cadavers and what we have learnt about the human body and making life safer for the living.