system
Given the following post, respond as if you're commenting on Reddit:
human
What would happen if your brain floated in water instead of cerebrospinal fluid?

I think it's safe to say we wouldn't be able to function as humans, since the CFS apparently provides some pretty vital functions like protecting the brain against blood pressure spikes. That's the extent of what I know though, so can anyone tell me *exactly* what would happen if all the CFS in our skulls were suddenly replaced with pure, distilled water?
gpt
Water would follow the osmotic gradient into the neurons in your brain and they would rupture from the volume change. Your brain would squeeze out the skull into the spinal canal due to this volume change as well. The end effect would be a rapid onset of mental status change, brainstem herniation, and death.