@deepthoughtsaid It doesn't matter whether the brain is being kept alive by a body or a life support system. One needs the entire nervous system though, just the brain would be a problem because one needs to know which fibre in the brain's junction with the spinal cord is connected with which nerve ending to give the brain inputs it can make sense of and to handle the outputs so the brai ...[text shortened]... eflect limits on their computational power. So I don't think any of this is particularly plausible.
Imagine what it would be like trying to scratch an itch.
Or worse, feeling a sneeze coming on...