Russian computer scientist Valery Spiridonov, set to become the world’s first head transplant patient has scheduled the procedure for December 2017.
Now I'm curious... What WOULD be the characteristics for a body donor? Would it be similar to organ donors? Because I mean - they obviously can't take the body of someone who died of old age because that body is no longer reliable. Neither somebody ill, because the illness could also kill the head. Neither somebody completely healthy because that would be unethical.
And that raises even more question. Ethically - are we going to allow "critically suicidal" but otherwise completely healthy people to donate their bodies?
What about body... head... What would reject what, and what would be the consequences, and how the hell can we calculate the compatibility between two sets of systems - circulatory, lymphatic, nervous.... And let's just hope that most diseases (like the one this patient has) can't spread to a healthy body just like that.
It's truly an exciting moment in medicine I can tell. At least I'm positively excited.
And the ramifications - with lab organ growth being in the works, I can foresee in a few decades (if this test is successful) people getting full bodies grown, minus head (then again it MIGHT need at least a basic head to survive and grow properly - more ethics...) in case of accident.
And now I'm wondering what effect will this have on the elderly population - how long we could preserve a head for...
Hell - I just realized. While the ethics of it would be... dubious, if this succeeds we could, in theory, start trying brain transplants - have a full grown body with an older brain for "another lifetime". Then again - I don't know how long a brain can actually live for...
As a side note - I am ALSO wondering how much of this research would be useful in "transhumanist" work - how much of it could be adapted to make electromechanical bodies compatible with our nervous system. Brain-in-a-jar-in-a-mech, anyone?
TL;DR: THE HYPE IS REAL. I can see SO MANY implications for this. This is as big, if not bigger, than generalized AI in terms of ethics and possibilities.
- Now I'm curious... What WOULD be the characteristics for a body donor? Would it be similar to organ donors? Because I mean - they obviously can't take the body of someone who died of old age because that body is no longer reliable. Neither somebody ill, because the illness could also kill the head. Neither somebody completely healthy because that would be unethical.
If it is anything like a hand or face transplant you need the following:
1. The tissues must match and be compatible for the transplant. This is the same as any organ donation.
2. The physical size of the donor must be within a tolerance determined by the transplant team. Not too tall, not too short etc. Big people have big blood vessels and the mismatch at the connection point can and does cause issues. Tendons that are not similar in size won't work correctly. With a head transplant, I would assume that the spinal column has to be the same size in both head/neck and body. There are also size related issues to the windpipe and esophagus that need to be considered.
3. The physical condition of the donor parts must be compatible. Skin color, hair, age even tattoos all have to be given consideration. A pale white man's head on a dark skinned female body would not work for multiple reasons for example. You can put a female donor's kidney into a male body, but for external parts you want male to male, Caucasian to Caucasian etc.
4. The mental state of the, what are we calling the head guy... donor? Body recipient? The head dude must be in a mental state to stick with their drug regimen to reduce risk of rejection. A rejection of the donor would be fatal in this case. Then there is the mental strength needed to go through the physical therapy to learn the new body. Hands will react differently, arms will be slightly different lengths than the previous host, legs and knees different and so on.
That is off the top of my head, and I bet I'm not even thinking of the deep mechanical issues that the transplant surgery needs to deal with like the spinal fusion, or that as far as I am aware nobody has been able to repair a fully severed spinal column.
- Then again - I don't know how long a brain can actually live for...
There are still two people left alive who were born in the 1800's. And that is your off-topic brain bending fact of the night.
Awesome - though I have two more things to say:
First, on a HUMAN they haven't "repaired" a fully severed spinal column - because 99.99% of the time, because of the sensitivity of the nerves, there's massive inflamation that happens - and it cuts off blood flow, preventing healing and further damaging/killing nerve cells. BUT they HAVE healed spinal cord injury, in rats... using something very close to blue food dye. And they already know it's non-toxic (except probably California which says it's carcinogenic, as always) because of how much of it humans consume on the regular. The only side effect (because it was an intravenous injection - because as it turns out, not only does blue food dye help prevent nerve inflammation, but it also crosses the blood-brain barrier) is that it turned the rats blue - which I'm not convinced will be as much of an issue in humans, and can probably be counteracted somehow. Sources for this: 1, 2, 3
Second, you made me realize something. Barring some incompatibility we discover,
- for external parts you want male to male
this does not have to be true. If there's enough donors, I can entirely see a market for transgender body-swap, which would have several advantages over current gender reassignment surgery - most notably working sexual organs of the desired gender (if everything goes well).
- this does not have to be true. If there's enough donors, I can entirely see a market for transgender body-swap, which would have several advantages over current gender reassignment surgery - most notably working sexual organs of the desired gender (if everything goes well).
My statement about "male to male" or "female to female" parts has nothing to do with gender or genitals. Men have thicker muscles, stronger tendons, more blood vessels and a different physiology than women. This is a very real issue in things like heart and lung transplants. 90% of the people on the heart transplant list are men, and men cannot use female hearts. Organ donors are split roughly 50-50; then you have to get into the tissue and blood type matching etc. Another example is female lungs don't fit into a male chest cavity. It works the other way as well, male hearts are not a good fit for female donors with a significant greater risk of rejection. Even kidneys, where the new kidney is inserted alongside the existing and the 'bad' organs left in the patient, need to be inserted into the same gender recipient as donor. The kidney thing shocked me. Kidneys sort of just sit there and if there was any organ that did not care about the size or gender of the recipient it should be kidneys.
Paper on Kidney gender mismatch here
Composite tissue allotransplantation is fascinating. There is so much going on during the transplant and it all has to match and line up. The surgeries are long and done under a microscope to meld together the tiny blood vessels, stitch the tendons together and fuse the bones while preserving the channels for the bone marrow so that it does not die in the recipient.
That's actually a very interesting phenomenon - thanks for the info! (Biology is fascinating...)