The continuity of brain and consciousness is not something I think we have a clear answer on. "Are you the same consciousness before and after a lobotomy" seems to be in the same class as "if you split the corpus collosum is it two consciousnesses now" and "Is Phineas Gage the same person before and after his accident?"

It will depend on whether you conceive of consciousness as arising from and dependant on its material substrate, or if you think consciousness is universal and that brains/minds are sort of like "antennas" that can pick up conscious signals, or any of many other theories of consciousness!