Amputee Controls And Feels Bionic Arm as Her Own

(UPDATE 03-05-2007 – Upon closer inspection, it is clear that while the surgery has enabled the woman to have sensation in the nerves of her missing hand when the surface of her chest is touched, the arm she is fitted with at the time of publication did not relay sensory signals from the arm back to her chest. As soon as she is fitted with an arm that has the appropriate sensors, however, she will not have to undergo further surgery to have this kind of direct feedback. Thanks to astute readers for pointing this out.)

The Guardian reports on an article published today in the Lancet about a successful surgical procedure giving an amputee a bionic arm that both responds to motor commands from her remaining motor nerves to control it and provides sensory feedback to sensory nerves when it is touched. If there was any doubt left, the worlds of neural prosthetics and brain-machine interfaces have officially collided.

The Lancet article is accompanied by two movies of the woman using the arm that you should really check out.

Given the recent progress in the decoding of motor signals from the brain and older progress on sensory feedback from neural prosthetics, this was to be expected. Nonetheless, watching this woman use her arm brings the message home in a visceral way. The spooky thesis of MIT CSAIL’s Rodney Brooks that “we will become a merger between flesh and machines” is one step closer today.

From the article:

Targeted reinnervation surgery was successful in this young woman. Four independent myoelectric sites were created that allowed improved control of a motorised artificial arm. Transfer sensation also developed; when the patient was touched on her reinnervated chest skin, she perceived the sensation to be in her missing hand.

An additional comment in the Lancet explains targeted reinnervation surgery:

Rather than record from these nerves directly, Todd Kuiken and colleagues report in today’s Lancet their development of targeted motor reinnervation (TMR), in which the disconnected ends of peripheral nerves are reimplanted into proximal musculature. Contraction of these proximal muscles shows the intended activation of the missing distal muscles. When combined with a myoelectric prosthesis, a command in the CNS to open the hand travels through its usual peripheral nerves, is amplified by the associated patch of reinnervated muscle, and is detected by myoelectric sensors, which trigger the prosthetic hand to open.

Todd A Kuiken, Laura A Miller, Robert D Lipschutz, Blair A Lock, Kathy Stubblefield, Paul D Marasco, Ping Zhou and Gregory A Dumanian, Targeted reinnervation for enhanced prosthetic arm function in a woman with a proximal amputation: a case study, The Lancet, Volume 369, Issue 9559, 3 February 2007-9 February 2007, Pages 371-380.


16 thoughts on “Amputee Controls And Feels Bionic Arm as Her Own

  1. This is so good. I can’t wait until people become cyborgs… I don’t find it spooky at all that we are going to become a merger of flesh and machine.


  2. Pingback: Spoon » Blog Archive » One step closer to cyborgs.

  3. I think fear is holding us back. we are (as a society) clinging to hard to being human. As though humanity was sacred, and immutable. I want to overcome my own biological limitations, and stop playing the DNA game. Evolution by natural selection sucks, we need to start evolving by conscious choice. Artificial hippocampus plus maxwell’s demon equals jumping into a posthuman existence. I just hope I can afford the modifications.


  4. This advance is awesome for amputees but I disagree with the impression that I get from some of the other commentors that it’s a big step towards escaping the limitations of our bodies. As far as I can tell, the crucial strategy that made this prosthetic successful is the attempt to stick within nature’s blueprint rather than trying to radically change things around using high technology:

    1) It seems like they’re saying that it was crucial that they used nerves that used to go to amputated limb. If you need to do this, that implies that the mapping of function to nerves is hard to change, at least in adults, and that doesn’t bode well for the idea of controlling radically unnatural prosthetics, or extra limbs, like the cyborgs of science fiction. (on the other hand, other prosthetic-type things seem to imply that this mapping is not so hard to change; for instance, the tongue prosthetic for vision)

    2) They used muscles to house and amplify the nerve signals that they wanted to read out, and they are proposing using the skin where the nerves are re-attached to provide sensation. The high-tech “posthuman” way would be to just interface with the nerves directly.

    So from the perspective of directly interfacing with our nervous systems in order to escape our bodies, this approach is not a clean design; it’s a hack. Not that I’m complaining; it’s a great solution to the problem at hand, that is, restoring lost function to injured patients; and it’s possible that for the next couple of decades at least, this sort of thing will be the best solution (perhaps nerves are happier interfacing with muscle and skin than with electronics).


  5. I would have to have Apple design the look of my new additions, since they seem to be the only fashionable technology designers out there anymore.


  6. In response to Sam:

    Your conscious choice is part of your biological limitations, it comes from DNA and evolution by natural selection. What your asking is to take the product (consciousness) of the process (evolution/DNA) to create a whole new process (posthumanity). How can you expect the product of this new process to be the same? How do you know that there is even a place for consciousness (atleast the kind we’re familiar with) in the future of posthumanity? Perhaps it is not the fear of humanity or being human, but it is the fear of the loss of our familiar consciousness that will be able to be changed unhindered into the future.


  7. Great! This will be useful to fight the atom sized robots that self replicate and heal. I can’t wait for that freaking day! It’s going to be like Christmas AND Thanksgiving every day for the rest of our short, robot controlled lives.

    Thanks science! No ill-willed person EVER could do anything EVIL with this! Way to think it through.


  8. I have been waiting for this to happen for a long time. You could go past the limits of physical human strength! You could even do this without cutting off any arms. You could add two other arms to your body! This is the coolest thing I have ever heard of. It’s like a dream. It’s only a matter of time before a human brain can be put inside a machine. You could get rid of pain completely and replace it with more pleasurable sensations.
    I would become a cyborg no problem. Of course there is the question of where the soul resides. I wouldn’t want to leave that behind. I might miss being fully human but you gotta take the good with the bad.


  9. “…Gentlemen, we can rebuild him, we have the technology. We have the capability to make the world’s first bionic man. Steve Austin will be that man. Better than he was before. Better. Stronger. Faster.”


  10. Pingback: Chayav or Patur? « Rejewvenate!

  11. Bayle:

    The limitations you bring up mark an important distinction between this type of prostheses (“simple prostheses”) and cerebral prostheses. We cannot (yet) replace parts of the cortex or create neurons (on the scale necessary to represent neural activity) and we cannot (although there has been some promising research on the formation and movement of neurons from stem cells in adults) force neural growth. I agree with you that although this is a large step forward, it is not the “cyborg” revolution, but it is definitely moving us closer. Perhaps a better example might be the recent approval of the FDA to install 50-70 bionic eyes that send signals to the optic nerve. Although this still uses neurons, it’s much closer to the type of interface you are hoping for. It will probably
    easier to apply the types of bioenhancements that the others write about with this sort of technology: I think it will be much easier to manipulate optic information/optic flow (i.e. a zooming feature) than to have some sort of super strength (which will more likely be dependant on preexisting muscle, weight of the arm and complexity of the interface).


    I appreciate the concern that I’m sure many people have, but I disagree with you that it’s a matter of not “thinking it through.” This is the natural progression of technology; the best we can do is to control its production, use and distribution. There will undoubtedly be many accidents: some parent holding a kid and accidentally squeezing too tight or something of the sort, but I hope that the companies producing these technologies will think of some type of limitation or check system. Incidentally, South Korea is drafting a code of robot ethics that will hopefully address some of your concerns.


    Interesting point about affording the technology. Perhaps what we will see is a new type of social differentiation: biomodified vs. normals. Many of the poor will probably fall into the latter category (along with a group of “tradionalists” who oppose the onset of radical technologies or the “unnaturalness” (perhaps certain religious groups will go along the same lines as well)). We already have a certain (commonly accepted) amount division centered around prenatal testing: the better-off are already living in a pseudo-Gattaca-world: artificial insemination and the termination pregnancies that promise genetic defects. And now that the location for eye color was determined (several months ago; turned out not be a single or specific gene, but a collection of SNPs (single nucleotide polymorphisms), I believe), it is only a matter of time until the better-off are selecting the sex and other physical features of our children to be. I’m not sure if this necessitates a healthier wealthy class, but that is not a possibility to be discounted: the rich may have the money (and soon the technology) to replace a sufficient number of parts and failing organs to lead healthier and longer lives. (That is probably a disputed point: health is also correlated with education and other socioeconomic factors.)


  12. Pingback: Jonas Mosskin» Blog Archive » Neurodudes om proteser

  13. We already are machines. Just biochemical instead of electro-magnetic/chemical whatever. Grow up, get over it, STFU. Waiting for my Ron Jeremy Electropenis.


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