# HowLong Till Human Brain Transplants Are Feasible? **URL:** \ **Category:** Factual Questions\ **Created:** [July 14, 2003, 2:34pm UTC](https://boards.straightdope.com/t/howlong-till-human-brain-transplants-are-feasible/188381 "2003-07-14T14:34:25Z")\ **Posts on this page:** 14\ **Page:** 2
**Author:** ![Marley23](https://avatars.discourse-cdn.com/v4/letter/m/45deac/32.png) [@Marley23](https://boards.straightdope.com/u/Marley23)\ **Post date:** [July 15, 2003, 6:41am UTC](https://boards.straightdope.com/t/howlong-till-human-brain-transplants-are-feasible/188381/21 "2003-07-15T06:41:57Z")
**Ralph** , did you see the rerun of the Star Trek episode “Spock’s Brain” the other day, too? > [@](#): > > Besides, if I were a surgeon, I’d rather face grafting a new head onto a neck stump You’d still have to reconnect the brain to the spinal cord, which is the biggie here. > [@](#): > > 1. If it’s immortality your after, I’d put more faith in computers being able to eventually replicate that thing we call the mind. Once we’re able to do that, it would be possible (although perhaps not easy) to build a computer model of your mind. This has struck me as impractical of late, since we ‘edit’ so much of what we see - memory is not a factual record, and we also remember and forget different things for different reasons. I’m not sure how a machine would replicate this. ---
**Author:** ![Mangetout](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mangetout/32/19_2.png) [@Mangetout](https://boards.straightdope.com/u/Mangetout)\ **Post date:** [July 15, 2003, 7:57am UTC](https://boards.straightdope.com/t/howlong-till-human-brain-transplants-are-feasible/188381/22 "2003-07-15T07:57:55Z")
Greg Egan wrote a story ‘Learning to be me’ wherein a durable electronic device is implanted into the skulls of newborn infants, learning to mimic every brain function (the idea being that if you capture brain function in a device, then you’ve got the person in there). But I wonder… even if we were able to do this - lets say we invented some kind of nanotech that could replace neurons one by one, would it be able to create a structure that was an exact duplicate? Would not the process of measuring the activity of a neuron actually alter that activity? ---
**Author:** ![Zoe](https://avatars.discourse-cdn.com/v4/letter/z/a4c791/32.png) [@Zoe](https://boards.straightdope.com/u/Zoe)\ **Post date:** [July 15, 2003, 8:11am UTC](https://boards.straightdope.com/t/howlong-till-human-brain-transplants-are-feasible/188381/23 "2003-07-15T08:11:39Z")
> [@](#): > > I think replacing chunks of brain with silicon or biological computers will be closer in range than transplanting the entire brain. Much more rewarding as well. Just think of having a chip the size of a quarter implanted in the back of the neck or upper back that had several hundred gig storage capacity. I wonder how many different artificial implants it would take before your brain ceased to be a human brain. Also, if you _could_ place a brain in another body, wouldn’t that be a body transplant instead of a brain transplant? 😃 ---
**Author:** ![Mangetout](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mangetout/32/19_2.png) [@Mangetout](https://boards.straightdope.com/u/Mangetout)\ **Post date:** [July 15, 2003, 9:52am UTC](https://boards.straightdope.com/t/howlong-till-human-brain-transplants-are-feasible/188381/24 "2003-07-15T09:52:15Z")
Here’s an idea then… (nanotech again) - inject a bunch of self-replicating nanoconstructors - their task is to set up camp at a suitable site in the spinal column, remove a piece of one of the vertebrae (reinforcing the space with a stronger, more compact material), then they construct a ‘universal coupling’ in the space, after that, they re-route the neurons through it, (one at a time, so there is no significant disruption to the function). When the time comes to effect the transplant, the universal coupling is separated and marry it up with a similar one in the new host body. The only tricky part is that the nanomachines have to understand the layout of the neurons in the spinal column, so that they can meaningfully connect them into the coupling and not end up with a leg motor neuron wired up to a finger etc. Well, it isn’t the _only_ tricky part, but it is certainly one of the biggies. ---
**Author:** ![Bosda\_Di\_Chi\_of\_Tricor](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/bosda_di_chi_of_tricor/32/16845_2.png) [@Bosda\_Di\_Chi\_of\_Tricor](https://boards.straightdope.com/u/Bosda_Di_Chi_of_Tricor)\ **Post date:** [July 15, 2003, 12:08pm UTC](https://boards.straightdope.com/t/howlong-till-human-brain-transplants-are-feasible/188381/25 "2003-07-15T12:08:49Z")
> [@](#): > > \*Originally posted by monstro \* > \*\*Why do we need bodies? > > I’m being serious here. > > Will there ever be a time when our decapitated heads will be able to be attached to a machine that aerates and nourishes our brains? Sort of like _Futurama_ except more complicated. What are the potential pitfalls in pulling off such a plan? \*\* No sex. Big downside from here, buckaroo. ---
**Author:** ![monstro](https://avatars.discourse-cdn.com/v4/letter/m/ba9def/32.png) [@monstro](https://boards.straightdope.com/u/monstro)\ **Post date:** [July 15, 2003, 1:30pm UTC](https://boards.straightdope.com/t/howlong-till-human-brain-transplants-are-feasible/188381/26 "2003-07-15T13:30:17Z")
Oral sex would be possible, no? ---
**Author:** ![Dogface](https://avatars.discourse-cdn.com/v4/letter/d/9d8465/32.png) [@Dogface](https://boards.straightdope.com/u/Dogface)\ **Post date:** [July 15, 2003, 2:53pm UTC](https://boards.straightdope.com/t/howlong-till-human-brain-transplants-are-feasible/188381/27 "2003-07-15T14:53:47Z")
Some of these plans are so elaborate that one might as well have the nanodingledangles just roaming around constantly refurbishing the body. Quick question: At what point of mental retardation does it become permissable to kill somebody? ---
**Author:** ![DocCathode](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/doccathode/32/18773_2.png) [@DocCathode](https://boards.straightdope.com/u/DocCathode)\ **Post date:** [July 15, 2003, 3:12pm UTC](https://boards.straightdope.com/t/howlong-till-human-brain-transplants-are-feasible/188381/28 "2003-07-15T15:12:09Z")
> [@](#): > > \*Originally posted by monstro \* > \*\*Why do we need bodies? > > I’m being serious here. > > Will there ever be a time when our decapitated heads will be able to be attached to a machine that aerates and nourishes our brains? Sort of like _Futurama_ except more complicated. What are the potential pitfalls in pulling off such a plan? \*\* Read William And Mary by Roald Dahl Fortitude by Kurt Vonnegut Re-Copying The Mind Into The Machine This raises the issue of pattern identity vs body identity. Would the mind in the machine be you or just a copy of you? Is there a difference? ---
**Author:** ![eburacum45](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/eburacum45/32/8690_2.png) [@eburacum45](https://boards.straightdope.com/u/eburacum45)\ **Post date:** [July 15, 2003, 5:56pm UTC](https://boards.straightdope.com/t/howlong-till-human-brain-transplants-are-feasible/188381/29 "2003-07-15T17:56:16Z")
## I particularly like the decapitation in _Use of Weapons_ by Iain Banks… the head is saved and kept alive- when they ask him how he feels he says ‘it’s just a scratch.’ ## Sure- sometimes the whole head will be kept alive for various reasons in the future- you may find that an entirely new body will be constructed to take the place of the old one, as headless accident victims will be in short supply- a new robotic body (hybrid creaturesof this sort are called cyborgs as you might already be aware:) ## you could get a whole wardrobe full of new bodies for different occasions. or a new body could be cloned by an (as yet undetermined ) method which produces a force grown body with no head; so there you are with an old head on a new body- the proud citizen of the future. * * * SF worldbuilding at [http://www.orionsarm.com/main.html](http://www.orionsarm.com/main.html) ---
**Author:** ![Sock\_Munkey](https://avatars.discourse-cdn.com/v4/letter/s/aeb1de/32.png) [@Sock\_Munkey](https://boards.straightdope.com/u/Sock_Munkey)\ **Post date:** [July 15, 2003, 7:50pm UTC](https://boards.straightdope.com/t/howlong-till-human-brain-transplants-are-feasible/188381/30 "2003-07-15T19:50:26Z")
> [@](#): > > \*Originally posted by Mangetout \* > **I also don’t think there would be any simple way to grow the clone without very specific bits of brain.** One would need to eliminate those sections of DNA reponsible for those bits of brain or block the enzymes responsible during the initial growth. The “Reptile” part of the human brain carries out the basic life sustaining functions of the body like breathing so the clone would only need a nutrient IV untill brain implantation. ---
**Author:** ![Ranchoth](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/ranchoth/32/1066_2.png) [@Ranchoth](https://boards.straightdope.com/u/Ranchoth)\ **Post date:** [July 15, 2003, 8:31pm UTC](https://boards.straightdope.com/t/howlong-till-human-brain-transplants-are-feasible/188381/31 "2003-07-15T20:31:28Z")
> [@](#): > > \*Originally posted by Marley23 \* > \*\* > You’d still have to reconnect the brain to the spinal cord, which is the biggie here. > > \*\* Well…that goes without saying, doesn’t it? I mean, _not_ having nerve-grafting technology at hand when you performed the operation would render the whole concept moot. But…even if we HAD the technology, If I were the surgeon, I’d still rather only have to worry about reconecting the spinal cord, than worry about reconnecting the spinal cord, AND the optic nerves, AND the Statoacoustic nerves, AND the Glossopharyngeal nerve, AND…well, all the other major nerves in the skull. ---
**Author:** ![Phage](https://avatars.discourse-cdn.com/v4/letter/p/a4c791/32.png) [@Phage](https://boards.straightdope.com/u/Phage)\ **Post date:** [July 15, 2003, 8:40pm UTC](https://boards.straightdope.com/t/howlong-till-human-brain-transplants-are-feasible/188381/32 "2003-07-15T20:40:54Z")
Why not just harvest stem cells? I seem to remember reading that they will change into whatever type of tissue they are introduced into, e.g. injecting them into a muscle will make more muscle, into the brain will make more neurons… You could either do the brain transplant with neuron therapy to get rid of the senility, or just do the entire body and let it integrate the new cells into the structure. ---
**Author:** ![Mangetout](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mangetout/32/19_2.png) [@Mangetout](https://boards.straightdope.com/u/Mangetout)\ **Post date:** [July 15, 2003, 10:17pm UTC](https://boards.straightdope.com/t/howlong-till-human-brain-transplants-are-feasible/188381/33 "2003-07-15T22:17:07Z")
> [@](#): > > \*Originally posted by Sock Munkey \* > \*\*One would need to eliminate those sections of DNA reponsible for those bits of brain or block the enzymes responsible during the initial growth. The “Reptile” part of the human brain carries out the basic life sustaining functions of the body like breathing so the clone would only need a nutrient IV untill brain implantation. \*\* I only went to armchair university to study genetics (and I didn’t graduate with honours), but I think I’m right in saying that it isn’t quite as simple as ‘bits of DNA responsible for bits of brain’ - I believe that it may be true that the proteins coded by the bits of DNA ultimately responsible for brain development, _may_ also be essential to other important non-brain functions. ---
**Author:** ![Mangetout](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mangetout/32/19_2.png) [@Mangetout](https://boards.straightdope.com/u/Mangetout)\ **Post date:** [July 16, 2003, 12:56pm UTC](https://boards.straightdope.com/t/howlong-till-human-brain-transplants-are-feasible/188381/34 "2003-07-16T12:56:44Z")
> [@](#): > > \*Originally posted by Zoe \* > \*\*Also, if you _could_ place a brain in another body, wouldn’t that be a body transplant instead of a brain transplant? 😃 \*\* From the point of view of the patient, yes, from the point of view of the surgeon, no, from the point of view of the patient’s friends and relatives… hmmm… _maybe_. [Previous page](https://boards.straightdope.com/t/howlong-till-human-brain-transplants-are-feasible/188381.md?page=1)