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Scientists Create a Way For People With Amputations To Feel Their Prosthetics (gizmodo.com)
An anonymous reader quotes a report from Gizmodo: Prosthetic hands have gotten increasingly sophisticated. Many can recreate the complex shape and detail of joints and fingers, while powered prostheses allow for independent, willful movement. But a new study published Wednesday in Science Translational Medicine offers a potential glimpse into the future of the technology: Artificial hands that actually feel like a living limb as they move. The researchers recruited people with amputations who had been given surgery that reconfigured certain muscle and sensory nerves surrounding the amputated limb, allowing them to control their prosthesis through intuitive brain signals (thoughts) sent to the repurposed nerves. Across a series of experiments involving three of these patients, the researchers attached devices that generated vibrations along specific muscles near the amputation site. When the device was turned on, these vibrations created an illusionary sense of kinesthesia -- an awareness of conscious self-movement -- in the prosthetic hand as the person performed tasks with it, both in a virtual stimulation and in the real world. The volunteers had amputations that extended just past their elbow as well as their whole arm. Not only did the experiment let them "feel" their hand as they opened and closed it, but the restored intuition allowed them to perform tasks without needing to constantly look at their hand. And coupled with vision, it gave them overall better motor control over their prosthesis.
Permanent neural electrodes present a lot of problems. One is that, to trigger a nerve, enough charge has to be deposited to trigger enough neurons, reliably enough, for the sensation to be detected and learned as valid. That's worked well in stable structures like the cochlear, where the bony channel surrounding the electrodes localizes the charge, but hasn't worked so well for othe permanent electrodes. If the electrodes are in muscle, the relevant wires tend to be bulky and interfere with movement, or they're fragile and they break. Also, the smaller the actual stimulator electrode (which is typically platinum melted to amke a ball on the end of the wire), the greater the resistance (which means more electrical voltage is needed) and the higher the current density around the electrode (which can cause electrolysis and tissue damage) and the greater the electrical noise around the electrode (which obscures the signal). Conversely, you can use larger electrodes, but the signal spreads out and triggers more neurons. And with neurons embedded in normal muscular tissue, well, things move and break your wires. It's easer in the head because you can embed the wires in stable bone, and even leave a physical jack screwed down on the skull.
You can play games to localize the signals: you can use short, triggered bi-phasic pulses to keep the pulses localized. You can even make "ghost" electrodes by triggering pulses at two adjacent electrodes to focus the trigger between those electrodes, but it's tricky. The field is filled with lots of "big ideas", actually getting them to work has turned out much more difficult.
Sadly, there is not currently any good way to really localize the signals to provide good resolution. Where the nerves are already laid out conveniently, such as in the spiral of the cochlea where deeper electrodes are lower frequency sounds. For re-routing touch sensations..... It's an interesting problem. I'd never expect it to approach the sensitivity of human touch. But proprioception, feeling movement... yeah, I could see that. It has enough duration that the a low current signal can accumulate and trigger local nerves.
When you fire your death-laser-blast into the skulls of mutant D-Bee Wizard abominations?
That's what a Borg needs to know.
After all he has pledged to eat his dick if bitcoin isn't at $100,000 by the end of the year.
this will solve the issue of people not treating their devices properly. Dropped your phone? A corresponding pain in your butt or whatever.
I suppose a clever hacker might have you feel someone else's prosthetic.
Anyone having trouble posting comments this morning?
not prostate. I must read gooder.
Don't fight for your country, if your country does not fight for you.
I thought this was known.
I was only tangentially involved, but during my diploma thesis about 10 years ago I was working on something in that area.
The gist of it is that the human brain's body image has a surprising about of plasticity, and when there's a closed feedback loop, it starts incorporating the artifical hand.
Excuse me while I go check the actual paper.
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No replies to see and I keep getting 1 moderator point, which does not expire when I use it!
THIS IS FREAKING COOL!
Will the scientists at slashdot.org find a way to show comments to their visitors?
Or is this far future tech for which humankind is not ready right now?
His shit needs amputated ASAP, it's infected necrotic tissue
You guys are talented. I haven't seen it break twice in a month like this ever!
intuitive brain signals (thoughts)
Thoughts are conscious experiences. One might send a move signal to a muscle but not a thought.
(-1: Post disagrees with my already-settled worldview) is not a valid mod option.
Suddenly, with linux/chrome, when I click on a heading it takes me straight to posting, and I can't see any comments, though the header shows some. I even have mod points. Help!
Why guess when you can know? Measure!
Now all we need is a prosthetic dick with feelings
Fix your goddamn website (please)
???
Unless an amputee is paralyzed, what is stopping them from feeling their prosthetic now?
I'm feeling my keyboard right now. Nothing to it.
Sloppy journalism.
test
Again?
...I read an article about this exact same technology. What improvements have been made since then?
One of our competitors trademarked the term "hypothesis". From now on, we will call them "boneheaded ideas".
Why am I a coward? I came to read comments.
Turns out this is actually amazing, but TFA doesn't quite make it clear. Keyword being: Kinesthesia
What I've been working before on was of course rather crude compared what they can do these days, but I thought this was still about the hand-brain feedback loop. It's actually on the next level. From the paper (emphasis mine):
"Substantial advances have been made in cutaneous touch feedback (pressure, tapping, moving touch, vibration, and texture) in humans through the use of implanted and regenerative neural interfaces (8–12). However, kinesthesia (pure movement sensation) is an entirely distinct sensory modality from touch (contact and force sensation)."
So basically this is about emulating the limb as a whole, not just the hand. If you're interested, you should go read the paper as well. It's probably accessible enough.
http://stm.sciencemag.org/content/10/432/eaao6990.full
Sensation hacking might be a new kink, but what about actually controlling it? What kind of new fun/trouble might that bring?
"Can't let you near the president, ma'am, your prosthetic hasn't been secured with the latest microcode. If you would please turn it off and use your left hand when you greet him, the secret service would appreciate it."
What you're writing is rather interesting in itself, but kind of misses the point here. You should go have a look at the paper and read the introduction. Especially the last paragraph:
"Here, we used vibration-induced perceptual movement illusions in a human bidirectional neural-machine interface to generate the kinesthetic sensations of complex synergistic grip movements. ..."
What the best way is to integrate man with machine (neurons to wires) is another subject, really. Eventually, they'll figure out the best way to do that, as well. This here is more on a fundamental level, namely about integrating the artificial limb into the human brain's body image. The brain has a surprising amount of plasticity, you just have to nudge it in the right direction, and these things will start feeling like the real deal.
Although it has to be said: the biological machinery attached to our bodies that makes our arms and hands is incredibly sophisticated. Mimicking it is no easy feat at all. It was both amazing and humbling to see back when I spent a little time working in that area.
(I'm the guy who posted below "This is new?")