Hypothetical Perfusion System

[RobotTemplar]

When I first read about a brain computer interface being used to enable a monkey to control a robot arm, this was the first ... application that occurred to me. As wonderful as the human body is, it is also very messy (eating, excreting, and so on), and it is vulnerable, on account of its very complexity, to many maladies (mainly, I am thinking of cancer, organ failure, and aging) which are difficult to treat.

 

So anyway, let us assume in the near future that the problems of neural scarring for BCIs and growth of artificial organs are resolved. Let us also say that we have the technology for electronic eyes and ears by this time that are close in capability to the real thing (etc. for any kinds of sensory prostheses). Finally, let us assume that one is able to surgically remove the brain and hook it up to a perfusion system before cell death sets in. This may sound absurd, but apparently at least one full on head transplant has been done (do a google search), and I think hooking up a brain to a perfusion system specifically made for the purpose might be a lot easier (apparently cooling the brain allows it to last a lot longer without a blood supply).

 

This perfusion system would consist of nodes to which the grown organs could be easily connected - allowing for easy replacement, as needed, very much unlike the human body. The artifical blood would be enriched with food, oxygen, hormones, or as needed. The brain would be able to switch between any number of physical actuation systems (robotic arms and so on) in order to interact with the environment. If BCIs ever became advanced enough, it might even be able to retain its human shape in the form of a virtual avatar or telepresent robot.

 

So yes, this may be a silly idea. In this scenario with artificial organs being easily obtainable, there is no real advantage except that you will perhaps be less likely to die from sudden organ failure. And you will still eventually go senile or have a stroke or die from brain cancer (though if we can do away with these problems...!). But are there any actual physiological obstacles? Just how feasible is this scheme of an artificial perfusion system with attached organs?

 

EDIT: This system could also be implemented with artificial (minimally biological) organs, I suppose. That's how I first envisioned it, before I heard about what scientists are doing with seeding organ scaffolds from other animals. It wouldn't matter if an artificial heart or lung or whatnot was as big as a house, as long as it worked.

Edited April 23, 2011 by Klaynos
requested by poster

[Marat]

You have to get a copy of the book by Chet Fleming, entitled 'If We Can Keep a Severed Head Alive' (St. Louis: Polynym Press) 1987, which describes Fleming's U.S government patent # 4,666,425 (complete with diagrams) of how to keep what he terms a 'discorp,' or severed human head, alive by connecting it with a number of mechanical organ substitutes. There is also a famous science fiction story entitled 'Donovan's Brain,' which explores the fate of someone surviving as a disembodied head in a tank who watches helplessly as his wife has an affair with someone else.

 

Photographs were published in 'Life' magazine in the 1950s of Soviet experiments in which a severed collie head was attached to the neck of another collie, and the entire ensemble (I think at one point it had three heads) was kept alive, albeit for a short period of time.

 

There are obvious limitations with any such experiment, mainly due to the difficulty of performing neurosurgically in some hyperadvanced way so as to reconnect all the nerves from the body to the head to construct an effective Frankenstein's monster. Fleming's 'discorp' would suffer from blot clots (despite having a heparin pump) and the artificial organs would provide a very poor quality of existence to the head connected to them, to say nothing of its dreadful experience in being alive but existing as a merely immobilized perceiver of events. Any effort to link biologial organs to the head to keep it alive would face all the usual problems with rejection and immunosuppression toxicity, and if animal organs were used rather than human, there would be the insuperable problem of hyperacute rejection from the xenograft.

[RobotTemplar]

...

Yes, blood clots are one problem that occurred to me. Advances in biomedical sciences may soon allow us to circumvent this, however.

 

My understanding of the organ scaffold/seeding process is that it eliminates the problem of rejection:

 

http://singularityhu...-in-rats-video/

 

See the Nova program "Can We Live Forever?" You use organs from animals or human donors - it doesn't matter - and you dissolve away all the cells, leaving only a protein "scaffold". Then somehow tissue engineers are able to reseed it with the transplantee's own cells, so there is no problem of rejection. Other methods of producing organs may be on the way - look up 3d printing of organs, for example.

 

I have read that artificial organs in that past have been problematic because it is difficult to make them small enough for implantation. However, when you are dealing with an immobile brain in a vat, it doesn't matter if your artificial heart or lung is several cubic meters in volume. I wonder if this might change things? I honestly have no idea.

 

I have seen Fleming's patent online. I will have to look up the book. I have heard about the Soviet experiments.

 

Remember that we aren't concerned about reconnecting nerves. We use a brain computer interface (one or more electrodes), implanted most likely into the motor cortex. This could allow you to control any number of robotic prostheses (perhaps one of the BCIs would allow the brain to switch to another prosthetic with a thought). This is completely doable right now, except eventually your brain will form scar tissue, and the BCI(s) will stop working.

 

The brain wouldn't be totally immobile, because it could use telepresent robots, for example. If BCIs ever become advanced enough (this is looking perhaps many decades into the future, if ever...or it might happen sooner), then it might be able to control a teleprescent robot designed to look exactly like its cast off human body (already done, to some degree). I am guessing that the peripheral nervous system would be much much easier to model on a computer than a CNS (because you don't have to worry about individual cells forming several thousand connections between each other...I think), so this also leaves open all sorts of cool options involving virtual reality.

Edited April 23, 2011 by RobotTemplar

[Marat]

The notion of building organs through the scaffolding process is a long way from being a practical possibility, which I why I returned to the idea of using transplanted organs. The general rule in medical science is that something which should logically be here tomorrow, given what is already known today, will in fact turn out to require another 50 years of work before it is ready for introduction into clinical practice. Just look at the route from the work of von Mehring and Minkowski in 1889 showing that dogs become diabetic when the pancreas was removed. It took another 33 years to go from there to discovering that a pancreatic extract could treat diabetes. In the Yale Medical Journal for 1926, four years after that, there were still articles being published purporting to show that diabetes was actually a side-effect of indigestion. Medical science is not only slow, but it even manages to go backwards at times.

 

I agree that the possibility of using unlimited space will improve artificial organs; this is already true with the artificial pancreas, which resists miniaturization but which works well enough in a massive format in ICUs. But for renal dialysis, the failure of the membranes to deal adequately with middle molecules will limit the usefulness of dialysis machines no matter what their size.

 

I wonder also what would happen to the brain surviving without normal sensory feedback. Some pretty freakish things happen in experiments with people under conditions of sensory deprivation, and similar problems might arise with a disembodied head.

[RobotTemplar]

...

 

You may be right about the slow pace of medical science. I guess I have a little hope because of the increasing pace of technological progress, especially in the field of biotechnology. A whole culture is developing around the idea of biological engineering, even outside the group of professional scientists. Look up DIY Bio, for example.

 

What you have to say about artificial organs is very interesting. This is the kind of feedback I was hoping for when I started this thread.

 

I have given some thought to this issue of cutting off normal sensory feedback, namely most (all?) of your peripheral nervous system. But since people with severe spinal injuries are able to survive (so far as I have heard), I don't think this would be a problem. Performing this operation without having at least one of the major sensory systems functioning to some degree (probably vision or hearing) would seem more like torture than medical intervention.

[sdenverjean]

The notion of building organs through the scaffolding process is a long way from being a practical possibility, which I why I returned to the idea of using transplanted organs. The general rule in medical science is that something which should logically be here tomorrow, given what is already known today, will in fact turn out to require another 50 years of work before it is ready for introduction into clinical practice. Just look at the route from the work of von Mehring and Minkowski in 1889 showing that dogs become diabetic when the pancreas was removed. It took another 33 years to go from there to discovering that a pancreatic extract could treat diabetes. In the Yale Medical Journal for 1926, four years after that, there were still articles being published purporting to show that diabetes was actually a side-effect of indigestion. Medical science is not only slow, but it even manages to go backwards at times.

 

I agree that the possibility of using unlimited space will improve artificial organs; this is already true with the artificial pancreas, which resists miniaturization but which works well enough in a massive format in ICUs. But for renal dialysis, the failure of the membranes to deal adequately with middle molecules will limit the usefulness of dialysis machines no matter what their size.

 

I wonder also what would happen to the brain surviving without normal sensory feedback. Some pretty freakish things happen in experiments with people under conditions of sensory deprivation, and similar problems might arise with a disembodied head.

 

yeah, you are right! I agree with you...but if that things will be realized....That is so great!....

That's gonna be one of the evidences of how powerful science today to the extent that people became abusive...

There's no more worries when we got sick....

______________________________________________

online medical supplies

[Joshua201]

yeah, you are right! I agree with you...but if that things will be realized....That is so great!....

That's gonna be one of the evidences of how powerful science today to the extent that people became abusive...

There's no more worries when we got sick....

______________________________________________

online medical supplies