The point posed by Penrose isn't (quite) whether the human brain is a Universal Turing Machine or not: it clearly is, in the sense that we can sit down with pen

The point posed by Penrose isn't (quite) whether the human brain is a Universal Turing Machine or not: it clearly is, in the sense that we can sit down with pencil and paper and emulate a Turing Machine of our choosing (infinite storage excepted, of course). Penrose's statement is that we are a superset of Turing Machines that can both emulate any Turing Machine and do non-computable things, too.