Board Thread:Naruto Discussions/@comment-11891028-20170719213849/@comment-734582-20170720140313

Kiadony wrote: Thing is, with Jinchuuriki, it's always pretty clear that there are, in fact, two separate consciousnesses within one body. It's never been the case with ET. That's why I think the soul, just like the body, gets replaced. (...) Or, perhaps you mean that the host is only alive in a physical sense? As in, they retain motor functions and all. In that case, I wouldn't say that it counts as being actually alive. They basically become zombies, husks controlled by someone else's soul. We saw with Naruto that as he lost control, his body turned into Kurama and his consciousness came under Kurama's control while trapped in the mental plane. So it seems logical to me that the same thing happens to Edo Tensei: the sacrifice becomes mentally trapped as the power sealed inside fully manifests and takes the shape of the sealed spirit, and gets access to all the spirit's powers and abilities.

Edo Tensei is basically the creation of a jinchuriki for a human, one that intentionally overwrites the human sacrifice. Unlike say Sasuke who was able to keep Orochimaru surpressed, or unlike Bee/Gyuki and Naruto/Kurama who eventually could coexist and freely swap.