Well all decisions ARE made in the brain, conscious or not, and whatever consciousness is, it resides in those neurons. That is also influenced by various inputs of the rest of the body, of course, but I think we can safely assume "self" exists in the brain. Thinking it reversely, can we really say an organism with various complex parts but no brain has consciousness?

You are not a disconnected consciousness, but some body parts are more easily discarded than others, and I think the brain tops most (all?) of the others regarding survivability - and is irreplaceable regarding the "self".