Cool? Yes. Practical? Functional? Not for all amputees.
The world’s first human testing of a mind-controlled artificial limb is ready to begin. A joint project between the Pentagon and Johns Hopkins Applied Physics Laboratory (APL), the Modular Prosthetic Limb will be fully controlled by sensors implanted in the brain, and will even restore the sense of touch by sending electrical impulses from the limb back to the sensory cortex. Last month APL announced it was awarded a $34.5 million contract withDARPA, which will allow researchers to test the neural prosthesis in five individuals over the next two years.
We’ve been reporting on major advances in artificial limbs for a while now, but this is the holy grail of prosthetic technology. Phase III testing – human subjects testing – will be used to tweak the system, both improving neural control over the limb and optimizing the algorithms which generate sensory feedback. The Modular Prosthetic Limb (MPL) is the product of years of prototype design – it includes 22 degrees of motion, allows independent control of all five fingers, and weighs the same as a natural human arm (about nine pounds). Patients will control the MPL with a surgically implanted microarray which records action potentials directly from the motor cortex.
Researchers plan to install the first system into a quadriplegic patient; while amputees can be outfitted with traditional prostheses, the MPL will be the first artificial limb that can sidestep spinal cord injury by plugging directly into the brain. This isn’t the first brain-controlled interface to be used in humans – we’ve previously reported on Braingate, a system that uses brain impulses to control computer cursors and restore communication to locked-inpatients. But the MPL will offer the first hard-wired neural control of bionic body parts, whether lost to injury or neurodegenerative disease.
Make sure you read the whole thing. Pretty cool, but realistically speaking someone like me will never get something like this. Much like hand transplant surgery, I only foresee this going to a double arm amputee. This isn’t exactly a “go enjoy the great outdoors” type of prosthetic either. Give this arm to me and I guarantee I’ll have it broken in a week just working around the house (can you use it as a hammer?) My body powered prosthesis has a Kevlar-esque harness, steel cables, and a carbon fiber socket and I still break it all the time. (Snowboarding season is particularly hard on my prosthetic. I had to repair it with ski binding hardware in Aspen last winter.) Please understand I’m not dumping on this prosthesis for the sake of dumping on it. Advances like this are great for amputees. But they’re not going to help all amputees. Technology like this is extremely expensive, extremely finicky, and not very durable. Hence the reason my expensive Myoelectric arm stays in a box in my attic and never sees the light of day.