What you're describing is a cyborg, or a collaboration between man and machine -- something that has arguably been going on at least since a caveman used a stick as a cane.. but it's much more advanced now.

Arguably, a cyborg is no longer fully human, or at least not only human, and as more human faculties are "enhanced" a smaller and smaller portion of the whole remains merely human.

Eventually, the part of the whole which remains human may become vestigial... and then what?