Terminally Ill Man Willing to Have World's First Full Head Transplant | Hacker News Reader

Terminally Ill Man Willing to Have World's First Full Head Transplant

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52 pointscpeterso47 comments

This comment summarizes my opinion on this subject: "The doctor can easily prove his technique works by transplanting the heads of two rats, preferably a white and brown one. If they survive and could walk around, not only will he get all the funding he wants, but the Nobel Prize in Medicine."

Well, I'd think rats pose different problems, but the essence is right.

I believe heart transplants were first attempted on sheep (wikipedia failed me on this one)

Seems like it has already been done:

In 2002, other head transplants were also conducted in Japan in rats. Unlike the head transplants performed by Dr. White, however, these head transplants involved grafting one rat's head onto the body of another rat that kept its head. Thus, the rat ended up with two heads.[10]

This has been done over 100 years ago with dogs.

I consider that to be even better! Did the other rat's head have any way to control anything in the body, or was it more like a guest?

I'm guessing it's more like it died after a short period of time.

If you look at the history of head transplants (yes a gruesome area), they ALL end badly for the subject.

More of a body transplant, no?

This annoys me too. It's not a "head transplant". You can't get a new head. You are your head. You're getting a new body is what's happening.

Well technically you can get a new head. Once we figure out how to laplink your brain data over.

How sure are you of that?

What if it turns out that the brain is only a user interface and hardware abstraction layer to the body, with "you" actually being a colony of microbes living in the body (mainly the gut)?

Funding & staff are not there!

Key quote "The cost... is estimated at over $10 million, ... the doctor has failed to secure funding for the surgery itself and for the staff of 150 doctors and nurses"

I'd suggest focusing on reattaching people's own severed spinal chords, to perfect the procedure before doing something as risky and speculative as a whole head transplant. If he can demonstrate that he can reliably reconnect all the correct nerves in one person's spinal chord, it would be a major breakthrough for millions of patients with spinal chord injuries, and then we can begin talking about connecting other people's, which I assume have different "pin-outs".

Fixing a broken spinal chord is probably rather more difficult (based on my extensive and indepth knowledge of the subject [ * ]), as there's likely to be a substantial section of damaged chord --- crushed, for example. A clean cut through an undamaged chord would provide two relatively undamaged surfaces. I have heard of work in regenerating severed spinal chords in rats.

I'd be more inclined to be worried about whether the neurons on one side can usefully bind to the neurons on the other. AFAIK the nerve mapping in the spinal chord is more or less random. The rat experiment wouldn't test this, of course.

[ * ] Disclaimer: while I have in-depth and extensive knowledge of some subjects, this is not one of them.

That makes sense, but as you say, the clean cut might not help the mapping problem. Even if you can somehow figure out which ones belong where that must be some very challenging microsurgery.

Maybe it would be possible to make a electronic, prosthetic section of spine that can be reconfigured on the fly, a bit like an FPGA, that might be useful for both injuries (where a damaged section needs to be replaced) and clean cuts with unknown mapping. Unfortunately these kinds of brain-computer interfaces seem prone to scarring, weakening the signal over time.

It's probably easier to just let them hook up randomly and then stimulate the brain into relearning the mappings. Infants do this as a matter of course (that's what a lot of the random flailing babies do is for). An adult brain may need a substantial amount of chemical help, though.

Ah, here's a short article on the work with rats: http://www.iflscience.com/brain/new-drug-boosts-nerve-regrow...

On Wikipedia i find 'It is argued that several up to now hopeless medical conditions might benefit from such procedure.[9][15]'.

Many people's initial reaction is disgust. Which i don't blame them for. But what if we can move past this? It might be a great medical advancement.

doesn't it just replace it with another (nearly) hopeless condition? success presumably means total quadriplegia - and this exacerbated most likely by 'total body rejection' - or maybe even 'head rejection' depending on who is in control!

More on Dr. Hunt Batjer's opinion of the operation:

> The problem is, fusing a head with a separate body (including spinal cord, jugular vein etc) could result in a hitherto never experienced level and quality of insanity.[1]

[1]: http://www.independent.co.uk/news/science/man-undergoing-hea...

Exciting stuff, to be sure.

This TED talk from Dr. Canavero explains it a bit further.

https://www.youtube.com/watch?v=FmGm_VVklvo

The assumption of the doctor is that all nerves in the spines of two organisms are organized in exactly the same way. IANAMD, but this seems a bold assumption.

Certainly IANAMDAW but cases with people who have suffered from paralysis have shown that the brain has the capacity to rewire things through physical rehabilitation exercises, so maybe it is possible.

Seems difficult to exercise something like liver function and stuff. But yeah also IANAMDAWTF and the man is dying. Go for it, I'd say.

http://en.wikipedia.org/wiki/Ship_of_Theseus

As it stands, there's a simple answer: The brain. The person is defined by having a specific brain; you can swap out literally everything else and the person will still be the same person.

This will be more relevant when pieces of the brain are being swapped out.

Though I find it hard to relate to, many people consider their bodies to be essential to their identity — they wouldn't be them without it. These people find our intuition about what is essential similarly foreign.

Some people have body dysmorphia issues, and some people just really identify with looking a specific way. I understand that. However, some people really identify with living in a specific location, too, but we don't usually regard moving day as the death date of the person who moved.

To be fair, AFAIK we don't really know how much the rest of the nervous system is "attuned" to being connected to a specific brain and vice versa. That is, even if the brainstem could be 100% connected to the spinal cord, we don't know how hard it would be to adapt to the new body. Could it result in something resembling the alien hand syndrome [1] or body integrity identity disorder [2], for instance?

[1] http://en.wikipedia.org/wiki/Alien_hand_syndrome

[2] http://en.wikipedia.org/wiki/Body_integrity_identity_disorde...

How do you know that we can swap everything else and the person will still be the same person?

Because we've done it.

OK, that's a bit facetious. A combination of existing transplantation procedures (heart? check. liver? check. kidneys? check...) and the fact that sometimes people need things removed but not replaced (thyroid, for example) leaves nothing but the brain as the organ which can't be removed and/or replaced without changing who the person is.

There's quite a big gap between "some bits have been removed or replaced" and "the brain is the only bit that can't be replaced" without changing who the person is.

The nervous system (of which the brain is but a part) is quite a large and complex thing, and there is no guarantee that one's conscious being is tied to that set of neurons in one's head and not, for example, to the extended set below the neck. There's evidence that certain functions are performed mostly or wholly within the brain, but no evidence of consciousness, which is what I think you mean by "changing who the person is".

Heart? Liver? Kidneys? Thyroid and appendix and gallbladders? They ain't got nothin' on the nervous system when it comes to me.

well, I don't really think this is the case, not for metaphysical reason or such, but because glands and the chemicals they produce have a high impact on how the brain functions

http://www.jabfm.org/content/23/5/677.full

I'd argue that the completely different chemical balance the brain will be subject to will cause dramatic behavioral swings, even if the patient memory and skills might be maintained (well, not the motor skill, I guess)

Is this even legal? If a procedure is 100% lethal, wouldn't it be murder?

I mean it is murder even if both parties agrees right? What is different in this case

You're right; if the doctor demonstrates no malice it would be involuntary manslaughter, not murder.

If the procedure is 100% lethal in theory, it's doctor-assisted suicide, which is legal in some jurisdictions (in America) and illegal in others.

If the procedure is 100% lethal in practice, but survivable in theory, it's medical research, and if good, non-coerced informed consent is given, I have a very hard time seeing any prosecutor prosecuting the case as even manslaughter or similar.

After all, there are other procedures which are only performed when there's a small hope of success; CPR out in the field is one of them. (High-end survival estimate is less than 20%, more likely less than 10%.)

http://www.cnn.com/2013/07/10/health/cpr-lifesaving-stats/

http://apps.health.qld.gov.au/acp/Public_Section/Resuscitati...

Another comparison would be bone marrow transplants, which can have a survival rate of 15-20% in some cases… but it's still better than not doing anything.

> the new body would come from a donor who is dead but otherwise healthy

Seems like a waste of a bunch of organs that could change many people's lives...

Why is that complaint valid? When this recipient dies, those organs can be used to change many people's lives.

>When this recipient dies

I would say if not when (nitpicky)

You mean there's a chance that this might render him immortal?

Medical science has to move forward, no?

Medical science has, however this Doctor is just making an outlandish claim. There have been no tests on animals that worked and he's just hoping his method of joining the spinal cords will work.

This isn't medicine, this is just someone with a superiority complex.

Only within certain ethical constraints. Otherwise you're giving the nod to things like eugenics, which is demonstrably a bad idea.

"the new body would come from a donor who is dead but otherwise healthy"....

LOL

While the procedure itself is clearly outlandish, is it that difficult to imagine a patient that died from brain-related complications (leaving the rest of their body in otherwise good shape)?

What about bullet in a head?

That would do it, yes.

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