I believe you are mistaken. First, you assume the brain function is effectively calculable. It is not. At least not at the level relevant to this discussion. Second, I think you assume if a device is computationally equivalent to a Turing machine it must have software and hardware as distinct components. Church-Turing thesis does not claim that and I believe it generally is untrue.
Imagine an expanding air balloon. Is the function it calculates effectively calculable? What is hardware and what is software in this case?