I guess I’m a bit confused - what would be an equivalent to a “steering wheel” in the context of a human brain as an “engine”? Or would this steering wheel be p

I guess I’m a bit confused - what would be an equivalent to a “steering wheel” in the context of a human brain as an “engine”? Or would this steering wheel be part of the brain? If so, why do we need to separate the two in the context of an LLM?