Scientists have been carrying out head transplants on animals since the 1970s, when a monkey's head was moved to another monkey's body; the resulting creature survived, paralyzed, for a few days. But so far, no one has attempted to put a human head on a different human body. That's because, in part, they haven't had a way to properly connect the donor body's spinal cord up to the head, so the head-body hybrid would be similarly paralyzed below the transplant area. But a new paper by an Italian neuroscientist says the technology now exists "for such linkage," Quartz reports.
Dr. Sergio Canavero believes the best method would be to sever both spinal cords with an ultra-sharp knife, then rapidly fuse the two together mechanically, using plastics like polyethylene glycol, which has been successfully used to fuse severed spines in dogs. (Spinal cords from two separate animals have not yet been connected though.) Popular Science states the obvious: This kind of transplant would be "enormously complicated," and involve reconnecting much more than the spine: bones, tissue, and millions of nerve fibers. The reconnection procedure would be strict to the extreme: The heads would have to be cut at precisely the same moment and then cooled to between 54.6 and 59 degrees, for instance. Theoretically, the procedure would offer paraplegics the chance at a new body. But it wouldn't come cheap—Canavero estimates it would cost at least $13 million. (In the meantime, this amazing paralysis breakthrough is a reality.)