This week’s entry: Head transplant
What it’s about: Scientists have long dreamed of cutting someone’s head off and putting it onto someone else’s body. Yes, there are altruistic reasons for doing this—ideally doctors could one day take the head of someone who’s paralyzed, has lost limbs, or has other serious medical issues, and graft it onto a healthy body. Or, more likely, you could finally create a plausible scientific basis for your screenplay to Face/Off 2: Head To Head.
Biggest controversy: While no one’s successfully transplanted a head, there’s a long, gruesome history of making attempts with dogs. As early as 1908, French organ transplant pioneer Alexis Carrel and American physiologist Charles Claude Guthrie attempted to graft a dog’s head onto a second dog (with the second dog’s head still intact). The grafted head initially showed some basic reflexes, but died soon after and the intact dog was put down.
In 1954, Soviet surgeon Vladimir Demikhov, who had done legitimate work improving the coronary bypass, attempted to graft not just a dog’s head, but also upper body and front legs onto another dog. He seems to have performed several such experiments, and one dog lived for a month after the surgery, but the rest died after only a few days.
A decade later, Robert J. White was grafting “only the vascular system of isolated dog brains onto existing dogs,” but by 1970 he had graduated to monkeys, decapitating one and grafting another monkey’s head onto it in four separate experiments. The grafted heads could chew, swallow, and track objects with their eyes, but success was short-lived. The high doses of immunosuppressive drugs he had to use, and not the transplant itself, seems to be responsible for the monkeys’ quick death.
In the last several years, Ren Xiaoping, who participated in the first successful hand transplant, has been transplanting the heads of mice, and his subjects have survived as long as six months.
Thing we were happiest to learn: Head transplants have long provided fodder for pop culture. As far back as the 1925 book Professor Dowell’s Head, the titular doctor is killed by his assistant, who keeps his head alive to reveal all of his medical knowledge. The assistant then transplants a woman’s head onto a new body, but his unethical experiments are exposed by his assistant. Plenty of fun late-night movies also involved head transplants, including The Brain That Wouldn’t Die, The Thing with Two Heads, The Incredible 2-Headed Transplant, and of course “The Thing With Two Heads” from “Treehouse Of Horror II.” Human-animal head transplants have also given us Marvel Comics’ Gorilla-Man (not too late to get him into the MCU!), Dav Pilkey’s Dog Man series, and one memorably off-putting segment of Mars Attacks!
Thing we were unhappiest to learn: Transplanting heads ain’t easy. As with any transplant, the organ needs to be kept alive, which is more difficult in the case of the head, as the brain needs a continuous flow of blood to survive. The risk of transplant rejection is at least as high as it would be in any type of transplant. And we can only speculate as to the long-term psychological effects of going through life with your head on a different body than the one you were born with.
But the real challenge is the nervous system. The animal experiments mentioned above managed to get blood-flow to the attached head, but with short-lived that success. And no one has yet tried to connect a spinal cord—each nerve would have to be reattached in the correct place, otherwise the subject would be completely paralyzed.
Also noteworthy: While there are obvious issues with head transplants, and especially with the animal experimentation that’s occurred in the field thus far, virtually every form of transplant surgery has met with objection. When Joseph Murray performed the first kidney transplant in 1954, he was accused of playing God, and hand and face transplants have each met with objections of being unnatural.
Best link to elsewhere on Wikipedia: Related to the head transplant is the idea of an “isolated brain,” commonly thought of as a brain in a jar. Again, scientists have experimented with animals, going as far back as 1857, when Charles-Édouard Brown-Séquard kept a decapitated dog’s head alive through constant infusions of oxygenated blood. This has been an even more common trope in sci-fi, from Doctor Who to Star Trek to A Wrinkle In Time to Futurama, but the isolated brain is also used as a philosophical puzzle. What would a brain experience with no body to provide stimulus? And if the brain were artificially stimulated (i.e., hooked up to a computer that provided sensory input), would there be any way of telling the artificially generated reality was a false one?
Further down the Wormhole: Both head transplants and isolated brains are under the “biomedical” category of Wikipedia’s emerging technologies category. Also in the category is strategies for engineered negligible senescence, a fancy name for medical science’s efforts to halt or reverse aging. While aging is still an inevitability for everyone, (apart from these 15 celebrities! What they look like now will shock you!), some animals experience negligible senescence, meaning they don’t show typical symptoms of aging like loss of fertility or increased likelihood of death. We’ll look at these near-immortals next week.