Biology/Technology question...

[Singular Intellect]

I have what I think is an interesting question regarding human existence and technology...or at least one I'd like an answer to if possible.

Many of us science fiction fans remember the classic movie Robocop, where a dying policeman's brain is removed and planted into our fearless robotic police officer.

My question is, how plausible is this concept? I'm not referring to the mechanical robotic body aspect, but rather the very act of seperating a human brain from a human body, while keeping it alive and presumeably healthy. Is this even possible with today's technology? Do we have the technology and know how to keep a human brain functioning without any organic body whatsoever to sustain it?

I know that we currently have the technology to sustain human life despite massive failings of the natural body, but just how much can we compensate for? On that note, does sustaining a human brain become easier or harder if you have complete disregard for the rest of the body?

What would be required to perform such a procedure, even if in theory? Or do we yet have to learn enough to even guess at such an answer?

[JointStrikeFighter]

There was an experiment done once by a scientist whose name I forget, but a decapitated dog's head was kept alive by feeding it blood directly from the jugular of another dog. Read into it what you will.

[Junghalli]

I doubt we can do something like that, reliably anyway, simply because if it was feasible it would probably have been used at least once or twice by now, to save the brain of somebody with a terminal disease.

[Modax]

A robot housing a human brain would need to have an artificial heart, to pump the blood, and a replenishable supply of glucose to put into the blood (so the brain can manufacture ATP.) It would also have to have a way of supplying amino acids, so the brain can produce proteins for the repairing and constructing new cells. So in other words, putting a brain in a robot just doesn't make sense. You would need some sort of extremely sophisticated nanotechnology to create all the macromolecules involved in running the brain.

[Modax]

Oh yeah, one other thing...the robot would also need artificial kidneys to filter the blood, and a system for removing and recycling waste products.

[Junghalli]

If you've got the tech to do that you'd probably be better off just transplanting it into a specially grown brainless clone or something.

Actually, what about something like what the villain was doing in the second X-files movie?
Spoiler

He was dying, and saved himself by having his head cut off and attached to somebody else's body.

Would that be remotely feasible with present technology? I'd think hooking up the spinal column would be problematic, but what about just keeping the brain alive?

[Singular Intellect]

I'm really curious if it's simply medically possible to remove a human brain while not killing it, and keeping it alive and relatively healthy with technology (the issue of volunteers notwithstanding).

Whether this would require artificial systems needing the space of an entire house (or bigger) or not isn't all that relevent to the plausibility/question regarding the concept.

Assuming the idea were physically possible (ie: keeping the brain alive and healthy), it then becomes a question if removal from the natural body would induce madness, especially if you couldn't provide it with sensory input/functions.

I know I'd certainly balk at the prospect of existence with no input whatsoever; no sight, sound, feeling...just awareness of existence. That would probably qualify as a method of torture, actually.

[Admiral Valdemar]

Short answer: yes. Long answer: get back to me in a few years.

[Fire Fly]

It's impossible to separate a human brain from the body and expect to keep the brain alive given the technology today. Depriving a brain of oxygen for even a mere few minutes will immediately result in irreversible brain trauma. The act of removing the brain is complicated by the fact that it is essentially anchored to the spine and several major arteries. The moment you detach the brain, there will probably be a rapid decrease in blood pressure to the brain and all of the blood that's in the brain will essentially drain out or become sedentary. Oxygen delivery, CO2 removal, glucose delivery, and a host of other essential functions will cease and brain neurons will begin to die immediately.



If you really wanted to try, you would first have to provide the brain with an exogenous source of blood, oxygen and other essentials. I think you can cut the brain from the brain stem without killing the brain itself. Experiments done on cats during the 60s and 70s where their brain stem was cut completely from the brain proper didn't result in death, at least immediately. There's an unlikely possibility that you could probably keep the brain alive but it isn't likely that you can make it function like a normal brain. Keep in mind that this is entirely speculation on my part. As far as anyone knows, it's medically impossible to remove brains and expect them to function normally.

[Broomstick]

Remember that in Robocop they didn't remove his brain, they removed his head.

There was a scientist who, some time past, transplanted the head of one monkey onto the body of another and said head/body combo did live for significant time afterwards, with the brain/head apparently regaining full conciousness. Of course, the monkey was a total quadraplegic, but we can sustain such for years at a time with proper medical support, and there was a need for immune suppresion, but apparently it IS possible to do this in monkeys. There is no reason to think it can't be done in humans.

I wish I could give more precise details but I'm sitting here with a very slow internet conneciton and without my normal referenes. Perhaps someone else can look this up.

One significant difference is that with the monkey head transplant the head/brain is supported by a monkey body evolved to support a monkey brain - biological systems are fiendishly complex in some respects. I'd be far more confident of making a robot body if, for example, we had reliable artificial hearts and a real artificial liver and lungs which is do NOT have at this point. Brains require some highly specialized chemicals and systems which can duplicate via artifical means (yet).

[Admiral Valdemar]

You've got four minutes of reserve energy in the brain's glial cell deposits before the thing starts significant cell apoptosis. Given sufficient support technology, you could remove the brain stem and implant it into a set artificial circulatory system while the finer things are sorted out later. So long as you can remove the brain intact, and not deprive it of oxygen and glucose for too long, you can conceivably extract and implant it at will.

This is beyond modern medical technology, however, in the future it may be far more doable given the advances in keyhole surgery, life support equipment and cryonics.

[Shroom Man 777]

If you can stop the heart for surgery and keep the rest of the body alive by rerouting the blood, which is what they do in surgeries, then this kind of thing shouldn't be too far off... in the next half-century or something.

But that's kind of daft. It'd be better to gradually replace the person's body with machines, than to take his brain off and plop it somewhere else. As for not having the required biologic systems for synthesizing all sorts of chemicals, you could just... uhh... use stem-cell grown organs or something.

Imagine a human whose brain is inside a robot body that looks like a refrigerator on wheels, and the robot body has shelves and compartments filled with all sorts of disembodied organs. And whenever those organs expire, you can just take 'em off and replace them with newly grown ones!

The robot shell would have buttons, and ECGs, and monitors, and things that make bleep-bleep sounds, and he'd have wheels with which to navigate, and a claw arm. And a cool synthesizer voice. And a drink dispenser.

[Count Chocula]

In addition to the issues listed above, principally blood supply and ATP manufacture, our brains produce a whole cocktail of enzymes (or tell our organs to produce those enzymes) based on processes that we simply don't understand yet. In addition to major veins/arteries, there are capillaries to/from the brain to the face, eyes, sinus, tongue, etc., and thousands, maybe tens of thousands, of individual nerve endings in the face, eyes, and spinal cord. I have absolutely no idea how you could mate those nerves up with a donor human body, much less a cybernetic body.

Then there's the autonomic nervous system to consider. Our brains control our bodies based on feedback loops, which are dependent on input from nerves in our bodies to the brain. How would a human brain in a cyborg body know what to do? Can we even conceive of a way we could build a mechanical body that would send a human brain the inputs it needs to "close the loop?" How would serotonin be produced? When would the transplanted brain know when to breathe, or accelerate the heart rate, or when to stop trying to lift a weight before the body was damaged? If you only had, say, 1/3 the neural inputs our brains evolved to look for, how would the brain respond? I'm guessing badly, but I'm a layman.

From what I read, cloning and memory duplication looks like a more sound, and closer time-wise, method to achieve the same effect, but I think we'll be dead or sucking our gums before it becomes possible in real life.

[Admiral Valdemar]

In addition to the issues listed above, principally blood supply and ATP manufacture, our brains produce a whole cocktail of enzymes (or tell our organs to produce those enzymes) based on processes that we simply don't understand yet. In addition to major veins/arteries, there are capillaries to/from the brain to the face, eyes, sinus, tongue, etc., and thousands, maybe tens of thousands, of individual nerve endings in the face, eyes, and spinal cord. I have absolutely no idea how you could mate those nerves up with a donor human body, much less a cybernetic body.

Stem cells. We need not have to do it manually, when several billion years of evolution can do it for us far better.

Then there's the autonomic nervous system to consider. Our brains control our bodies based on feedback loops, which are dependent on input from nerves in our bodies to the brain. How would a human brain in a cyborg body know what to do? Can we even conceive of a way we could build a mechanical body that would send a human brain the inputs it needs to "close the loop?" How would serotonin be produced? When would the transplanted brain know when to breathe, or accelerate the heart rate, or when to stop trying to lift a weight before the body was damaged? If you only had, say, 1/3 the neural inputs our brains evolved to look for, how would the brain respond? I'm guessing badly, but I'm a layman.

From what I read, cloning and memory duplication looks like a more sound, and closer time-wise, method to achieve the same effect, but I think we'll be dead or sucking our gums before it becomes possible in real life.

The autonomics etc. can be simulated. Unless you're arguing vitalism, there is no reason we can't reproduce these things, albeit, in a shiny robot body.

As for memory duplication, that isn't quite the same. A copy of the engrams of one person is a copy, not that person as we know them. It's subtle, but the consciousness is not the same and you cannot get a atomically accurate model anyway. The best bet is to replace neurones one at a time with synthetic ones via nano- microtechnology.

[Razaekel]

It's impossible to separate a human brain from the body and expect to keep the brain alive given the technology today. Depriving a brain of oxygen for even a mere few minutes will immediately result in irreversible brain trauma.

Not entirely true. Recently, there have been instances where application of full-body cooling increases the chance of survival for heart attack patients, and some extreme cases where a person has been without oxygen for 1-2 hours, in a very cold environment, and completed a full, or near full recovery, once warmed up to normal temperatures.
Secondarily, most of the brain trauma seems to come from the sudden reintroduction of oxygen to cells after a period of deoxygenation, not from the long term lack of oxygen. With this information, it could be possible to cool a person down, remove the head/brain, and as long as it is kept cooled and oxygen-free, it could last for some time while the surgeons transplant it.

source: link

[spaceviking]

There was a scientist who, some time past, transplanted the head of one monkey onto the body of another and said head/body combo did live for significant time afterwards, with the brain/head apparently regaining full conciousness. Of course, the monkey was a total quadraplegic, but we can sustain such for years at a time with proper medical support, and there was a need for immune suppresion, but apparently it IS possible to do this in monkeys. There is no reason to think it can't be done in humans.

I wish I could give more precise details but I'm sitting here with a very slow internet conneciton and without my normal referenes. Perhaps someone else can look this up.

I think your referring to Dr. Robert J White, apparently he did this in 1970. The monkey survived a week, he believed that with improvements in surgical technique it could be adopted to humans.

[Broomstick]

Yes, that's the one. Apparently it's also been done with limited success with dogs, too. The problem isn't so much transplanting the head as keeping it alive afterward.

[Starglider]

You would need some sort of extremely sophisticated nanotechnology to create all the macromolecules involved in running the brain.

I don't think so, conventional chemical synthesis should work. You can do that in a big lab and simply refill the tanks in life support system every day or so. This would be ridiculously inefficient for a single subject, but in a sci-fi world bulk manufacturing of the relevant biochemicals may be going on for other reasons (some of them are in reality).

Another option; in principle, you don't need a fullsize human organ setup just to support the brain. A set of key internal organs of about one third the former mass should do it. With sufficiently advanced genetic engineering, you could grow these, leaving more space and mass available for making your robotic body kickass. Plus let's face it, some organs such as the lungs are just inefficiently designed, blood oxygenation is relatively straightforward (compared to say digestion) and we could probably make an artificial version that is smaller, lighter and more robust (e.g. based on continuous flow through a grid of tubes rather than cyclical flow and a mass of little sacs).

[Singular Intellect]

Ah, so my dream of sticking my brain into a Terminator 101 chassis isn't as far fetched as it sounds!

But as StarGlider mentioned, I had suspected that in several areas we could significantly improve biological components; after all, it would be quite perplexing if engineers routinely commented on the inefficieency and delicacy of the human body if they couldn't at least improve upon much of it.

One additional question comes to mind though; assuming we have our human brain healthy, alive and functioning in our fictional artificial life support system, how long would we expect it to survive? Presumeably components could be swapped out relatively easily, so the brain's lifetime would not be limited by the failings of the supporting biological systems.

[Broomstick]

Another option; in principle, you don't need a fullsize human organ setup just to support the brain. A set of key internal organs of about one third the former mass should do it.

Possibly, less than 1/3. Remember there is considerable redundancy in the human body. An adult can live a normal lifespan with only 1/2 a functioning kidney (although some precautions will need to be taken to preserve health). You can live quite well with just one lung. Spleens are optional. And so on.

Plus let's face it, some organs such as the lungs are just inefficiently designed, blood oxygenation is relatively straightforward (compared to say digestion) and we could probably make an artificial version that is smaller, lighter and more robust (e.g. based on continuous flow through a grid of tubes rather than cyclical flow and a mass of little sacs).

If that's the case, why don't we have artifical lungs as we have artificial kidneys? The closest we have is a heart-lung machine or ECMO (ExtraCorporeal Membrane Oxygenation), both of which are severely limited and can only support life for very brief periods of time. Both are associated with brain damage or death in a percentage of patients.

It would actually be easier to replace digestion with completely processed nutrients in the bloodstream (the record for this sort of survival is 35 years) than to replace the lungs. You see, blood normally clots on contact with the gasses of which air is composed, yet the lung exchange gasses without this occuring. Quite a trick. We only get around the clotting while using heart lung machines or ECMO by massive use of blood thinners.

[Junghalli]

One additional question comes to mind though; assuming we have our human brain healthy, alive and functioning in our fictional artificial life support system, how long would we expect it to survive? Presumeably components could be swapped out relatively easily, so the brain's lifetime would not be limited by the failings of the supporting biological systems.

The brain ages too, so you might buy some time because you no longer have to worry about organ failure, but you probably wouldn't be able to live centuries or anything like that. Or maybe you could live that long, but your brain would be hopelessly decayed by then and you'd have long since been reduced to senility.

[The Duchess of Zeon]

One additional question comes to mind though; assuming we have our human brain healthy, alive and functioning in our fictional artificial life support system, how long would we expect it to survive? Presumeably components could be swapped out relatively easily, so the brain's lifetime would not be limited by the failings of the supporting biological systems.

The brain ages too, so you might buy some time because you no longer have to worry about organ failure, but you probably wouldn't be able to live centuries or anything like that. Or maybe you could live that long, but your brain would be hopelessly decayed by then and you'd have long since been reduced to senility.

It would be an acceptable temporary solution until we can fully transfer the consciousness to a computer system. Live a couple decades as a robot after you hit 95 or so, and then transition to being fully a computer.