Could the brain theoretically survive outside of the skull?

Answer 1

Brain isolation in vitro was demonstrated in the 1960s using Rhesus Monkeys. Brain transplantation has also been demonstrated using dogs, again in the 1960s. These types of experiments would rarely, if at all, be performed today for ethical reasons. Nor would researchers need to prove this. Of course it is possible...this was known to be theoretically possible prior to 1960. It's not that complicated theoretically, but it is practically impossible to mimic what nature gave us. All the brain needs is a blood supply, CSF circulation, and sensory stimulation/motor output. The last part, which was overlooked during those early barbaric experiments for technical reasons, is actually critical. Can you imagine being alive but not being able to see, hear, touch, taste, smell, sense balance/gravity - only imagine, like a dream, but without any means to interact with the world, such that your mind becomes a prisoner in your own brain? It's hard to imagine. But more importantly, harder to imagine why one would want to do this at all.

Answer 2

Not for very long. The brain is heavily dependent on a steady blood supply with its glucose and oxygen for survival. Under conditions where a heart stops, brain cells begin to die without any oxygen after about four minutes and irreversible brain damage is likely. Brain death will ensue shortly after that.