I knew you were going to say "Look at the video" which is why I pre-emptively wrote "The problem to those not familiar with a vegetative state is that they think the person in that state in responding to them because there are facial gestures and eye following movememnt. In reality it is just a reflex action."
A lot of people go through most of their life with only reflex reactions. Should we starve them?
Is that like the 'fish don't feel pain' factoid? How could anyone know this to be true unless a person in a vegetative state woke up and told them, 'it was just reflexes when I smiled at you.' But that wouldn't help the kill terri crowd's case much, would it?