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Brain Interface Lets Monkeys Control Prosthetic Limbs

Posted by timothy on from the what-did-you-do-at-the-lab-today-bonzo dept.

himicos was one of many readers to point out one recent success of scientists working to develop working brain-machine interfaces, writing "A team at the university of Pittsburgh has finally advanced a 2002 technology enough for use in prosthetic limbs, the targeted application all along. Training computer models to the firing patterns of the neurons in the parts of the brain that control motion, they are able to project the intentions of a monkey to a robotic arm, which follows the will of the animal. The sad thing about the articles is that the beauty of the mathematics used to create and train the models is totally ignored." Reader phpmysqldev adds a link to coverage at the BBC, and writes "This of course brings significant hope to amputees and other other people with physical disabilities." (Note that this research has been going on for quite some time.)

19 of 208 comments (clear)

  1. Forget Replacement Limbs... by crymeph0 · · Score: 5, Insightful

    How about custom appendages? If the brain can be trained to independently control a new arm, why couldn't it learn to control a genuine Doctor Octopus suit?

    --
    It should be illegal to say that freedom of speech should be limited.
    1. Re:Forget Replacement Limbs... by PachmanP · · Score: 4, Insightful

      How about custom appendages? If the brain can be trained to independently control a new arm, why couldn't it learn to control a genuine Doctor Octopus suit?
      Speaking from experience, it is because the grant money is better. If you say you need money to research brain/machine interfaces for prothetic limbs to help disabled people, you are more likely to get it than when you say you need the research to give yourself/your_cyborg_army superhuman appendages to be used for world domination.
      --
      You're thinking small. Why miniaturize the laser, when we could instead enlarge the sharks? -John Searle
    2. Re:Forget Replacement Limbs... by schmu_20mol · · Score: 2, Insightful

      Because the prosthetic is controlled by the very neurons which are normally used to control the monkeys now restrained arm. The research focused on using already 'trained' and known neurons within the brain and how to interface them with a prosthetic. Afaik, there's currently no research going on about using 'unnatural' or to the brain formerly unknown limbs.

      --
      "Nae Kin! Nae Quin! Nae laird! Nae master! We willna be fooled again!"
    3. Re:Forget Replacement Limbs... by khayman80 · · Score: 4, Insightful
      I would imagine the mental map we have of our bodies has four limbs. This would mean that, for purposes of sensation, motor control and proprioception, we can't operate more than four limbs at once. Why would we evolve the ability to control limbs that we don't even have? I mean, brains are flexible, but I would guess that trying to push the "body control/sensation/proprioception" map past four limbs may have some unintended (and possibly bad) consequences.

      An alternative might be the use muscles in the face to control extra limbs. Frowning would perform one action with the prosthetics, smiling another, etc. But this would be considerably more clumsy than the intended use- replacing a limb that doesn't exist on the physical body, but does have a designated place in the brain that controls it.

    4. Re:Forget Replacement Limbs... by street+struttin' · · Score: 3, Insightful

      Speaking from experience, it is because the grant money is better. If you say you need money to research brain/machine interfaces for prothetic limbs to help disabled people, you are more likely to get it than when you say you need the research to give yourself/your_cyborg_army superhuman appendages to be used for world domination. You have GOT to be kidding! Getting government grants to find military applications for otherwise harmless things is a staple of the defense program. If you have an answer to "How many Commies/Terrorists can it kill", you've got grant money.

      So go ahead and build your cybernetic superhumans to do your bidding, but you might have to sign a contract that says you'll do the bidding of the US government, too.
    5. Re:Forget Replacement Limbs... by Bones3D_mac · · Score: 3, Insightful

      I would imagine the mental map we have of our bodies has four limbs. This would mean that, for purposes of sensation, motor control and proprioception, we can't operate more than four limbs at once. Why would we evolve the ability to control limbs that we don't even have? I mean, brains are flexible, but I would guess that trying to push the "body control/sensation/proprioception" map past four limbs may have some unintended (and possibly bad) consequences.

      Personally, I see this problem as more the case that we've only been conditioned to handle that many limbs over years of experience versus any sort of hard limit being imposed. (Not to mention it kind of runs across the grain of that whole "evolution" thing being needlessly debated...)

      There have been numerous examples demonstrating that our brains are not only highly adaptive to new situations (such as the brain redistributing certain functions to different areas to overcome damaged areas), but are also highly receptive to new forms of input from external sources (such as invasive probing of the brain to create crude brain-to-computer interfaces to control simple devices, such as an on-screen cursor.)

      The larger issue is really more of a case of creating a proper and convenient interface for cyborg-like add-ons. For example, do we necessarily have to invade the brain directly, or can we simply use existing connections by connecting jumper cables to the nerves running down the spine. And if that isn't an option, can we create or add extra, custom nerve sets to the spine and create connections to the brain that way?

      Considering all that, a "third arm", or similar contraption is probably within the realm of possibility, but it may take time to adapt to and fine tune the system before it becomes effortless (or closer to that) to use. It's actually not all that dissimilar to the steps you have to go through for setting up a decent voice recognition system.

      --


      8==8 Bones 8==8
    6. Re:Forget Replacement Limbs... by TheLink · · Score: 3, Insightful

      "This would mean that, for purposes of sensation, motor control and proprioception, we can't operate more than four limbs at once."

      I'm sure that's wrong.

      We extend our mental maps to include vehicles, devices and tools that we operate on a regular basis. Believe me, some of us even feel pain when we ding our car on something. Some even feel pain if they get shot in a video game.

      The fact that many people can be trained to see with their _tongue_ means the brain is very adaptable.

      The Seeing Tongue:
      http://findarticles.com/p/articles/mi_m1200/is_9_160/ai_78681631

      Just because you start seeing with your tongue does not mean you lose sight in your eyes. So I do not believe that we are limited to controlling 4 limbs. When people use a tool they are skilled in, that tool becomes an extension of their body - and it does not even have to be physically connected to their body - ask people who do stunts with RC helicopters, or play FPS/RTS games.

      Once you practice enough, it becomes learnt and integrated into your brain, you no longer think "Ah I must press this to do X", you just think "I need to go here" and you do whatever it takes to get it done.

      A skilled typist does not think of each key stroke independently, the typist just thinks of the phrase (or sees stuff to type) and all the 8 fingers and 2 thumbs get it done. So controlling more than 4 limbs shouldn't be a huge problem.

      However, just like when you concentrate on something a lot, say drawing an intricate design, you may lose awareness of what's going on with your little toe (until something significant happens to it, or even is about to happen to it - incoming object via peripheral vision - in which case the rest of your brain brings it to your attention).

      --
  2. Re:PLEASE tell me it makes them type faster by maxume · · Score: 2, Insightful

    Well that explains SciFi movies:

    http://science.slashdot.org/comments.pl?sid=567543&cid=23585235

    --
    Nerd rage is the funniest rage.
  3. Re:Explain the beauty? by kalirion · · Score: 4, Insightful

    How would you explain the beauty of a sunset to the blind?

  4. Monkey's opinion by nategoose · · Score: 4, Insightful

    The monkey in the pictures had his own arms restrained within tubes so that he/she would be forced to use the mechanical arm in order to get the marshmallow, and the mechanical arm isn't oriented so that the monkey could possibly mistake it for his/her own arm. I can't help but wonder what the monkey's opinion of all this is. It's got to be more than a little confusing.

  5. Re:sci-fi pondering by somersault · · Score: 3, Insightful

    Do you merit all scientific advances purely by how much closer they're going to get us to the Star Wars universe? ;) I don't think that lightsaber mishaps are the only type that require the victim to use a prosthetic.

    --
    which is totally what she said
  6. Re:Explain the beauty? by jellomizer · · Score: 2, Insightful

    Oh yea that will be a big hit, for the general public. Showing all the math that needs to be done. or Show a picture of a monkey with a robotic arm. Lets face it math is not a spectator sport. To observe the beuity of it you will need to sit down and look at it proove it to yourself then you can admire it. However Most people don't have the time to sit down and follow equations that most mathamatitions follow the old scheme of using Greek symbols as shortcuts to (porposly) make it very difficult to read for non math majors. Heck I have a Math Minor and the symbols require me to look them up, and figuring out in what area the math is used the same symbol can mean different things. A simple example Pi in Geomontry is different then Pi in Statitics. Math is not a spectator sport to appreate its beuity takes time, if you are not intimatly involved with it it gets that much more cryptic.

    --
    If something is so important that you feel the need to post it on the internet... It probably isn't that important.
  7. Re:Explain the beauty? by hansraj · · Score: 5, Insightful

    I am amazed at the number of responses being just smug and claiming how you need to do math to appreciate the beauty. Reminds me of a guy doing PhD is Chemistry about effects of certain chiral isomer of nicotine on cancer. His first response when I asked what he worked on was "You won't get it". I am a PhD student in computational geometry and I frequently have to explain my work to relatives who have no idea about geometry. When I pestered the guy that whether or not he can explain his work to a layman reflects his understanding about his work, he agreed to try. Of course I could understand the central part once he replaced the technical name of the molecule with "a chiral isomer of nicotine". I am sure it could have been further simplified as "mirror image molecule of the stuff in tobacco" in case I didn't remember what "chiral" and "nicotine" are.

    On the topic, I am not entirely sure about the exact math used in the said experiment but based on the fact that the link points to the notion of "information content", here is my guess how it should work (at least in principle). I will try just because no one else seems to. Feel free to correct me.

    The state of the neurons of the relevant area of the brain (relevant for the goal in the experiment - say pick marshmallows or open the door) could be modeled as a random variable. The first problem when trying to figure out what a certain electrical activity in brain represents would be to figure out whether you are looking at a random electrical activity (brain doing lots of background work maybe) or some order (brain trying to focus and activate the subroutine for "move hand and open door"). This difference between order and chaos is captured in a neat formula describing the entropy or the information content of the random variable. Naturally, the less the entropy the more the order. I have no idea what possibly goes on after this step.

    In any case, now coming to the "beauty" part. Of course you need an eye to appreciate beauty for the notion is quite subjective. The remarkable thing is that a simple formula captures the vague notion of "order" that we all have. The formula might not be the most beautiful thing because as I understood from the article, the log term is somewhat forced to make sure different things add up nicely. But then, one could think of this very fact (the extra log term) as a neat mathematical representation of the notion that disorder should be able to be combined with another disorder to create something bigger.

    I hope my response is better than "drop whatever you are doing and go do a PhD in math before you can understand the beauty of math".

  8. Re:God hates amputees... by Anonymous Coward · · Score: 1, Insightful

    That's why humans are making this instead of leaving it up to God.

  9. Re:Explain the beauty? by NotBornYesterday · · Score: 2, Insightful

    You're right. What's really sad is the number of sighted people who can but simply don't bother.

    --
    I prefer rogues to imbeciles because they sometimes take a rest.
  10. Re:And just like that... by Anonymous Coward · · Score: 2, Insightful

    I notice nobody here gives a toss about the pain and suffering, and terror, that this poor creature has gone through, and all for naught.

    If this technology ever makes it to humans, it will only be after HUMAN experiments are done. Of course, the frauds who call themselves vivisectionists will say that "We couldn't have achieved the human version without first torturing - sorry - 'experimenting' on monkeys", but the first human version will fail, guaranteed. They will be EXPERIMENTING on humans, until they find out what works, as simple as that.

    This bullshit is all over the news because 'those in power' want to normalise these atrocities, and even have the gall to show video of this poor animal being tortured.

    Don't tell me, having invasive brain surgery and electrodes inserted into your brain has no after effects, i.e. PAIN. And I'm sure they just magically found the RIGHT part of the brain to insert the electrodes into, the first time they did it, right? I mean, it's not as if they've tortured hundreds of monkeys with this monstrous violence, in order to find which part of their brains controls their hands, no sirree...

    Perhaps you should ask yourselves - "Why am I incapable of feeling the suffering of others, and why is that not a problem?"

  11. Re:And just like that... by mpeskett · · Score: 5, Insightful

    You'd prefer they started out by sticking electrodes into humans with no idea what they were doing?

    Of course some experimentation will be needed when they move to human subjects, but a monkey's brain is similar enough to ours that they can get a starting point to experiment around, rather than working blind on a human subject.

    One other thing to note, there are no touch/pain receptors within the brain itself - people have brain surgery done while awake so the doctors can keep them talking and know they aren't accidentally removing something important. Once you've got an opening into the skull (which would be done under anaesthetic) you can poke and prod at the brain all you want without the subject feeling a thing.

    Oh, and its on the news because its interesting and something of a step forward scientifically. Quit it with the conspiracy theories please.

  12. Prosthetics Don't Have to be Replacements by rdmiller3 · · Score: 2, Insightful

    The really cool thing that they're totally missing is that prosthetic limbs aren't limited to replacements.

    Research has shown that the brain has the ability to handle additional limbs and/or senses. So if an amputee can learn to control a replacement arm, then a normal person could also learn to control an extra pair of arms. The neat thing is that the brain would just adapt to it and it would seem natural.

  13. Re:And just like that... by j_166 · · Score: 2, Insightful

    So I still don't get what you are saying. You don't want experiments carried out on humans, because they might die, and you don't want experiments on animals, because its cruel. How then do you suggest we as a society carry out research on the level that leads to neat things like artificial hearts and robotic monkeys (aka prosthetics controlled by your brain)? At some point you're going to have to implant some probes into someone's head. It just can't be done otherwise. Theory only takes you so far.

    "Animal 'research' is a fraud. Which is why we don't have a cure for cancer yet."

    I'm not sure I see the connection between these 2 thoughts. Animal research is a fraud, therefore we don't have a cure for cancer. That just doesn't logically make a coherent argument. Maybe we just have not been able to find a cure for cancer yet because its a very complex problem. What does the cure for cancer have to do with animal research?

    "And why idiots like you still believe that 'AIDS' is caused by 'HIV', and blindly parrot whatever the MSM tells you..."

    OK Dr. Anonymous, tell me, what is AIDS caused by?