Everyone's favorite secretive research organization, the Defense Advanced Research Projects Agency (DARPA), is working on a new set of prosthetic limbs which can be controlled simply by the power of thought.
Such faux limbs could soon become commonplace thanks in part to rapid progress in the development of neuromuscular interfaces - miniature electrodes which can be surgically embedded in the remaining muscle structure of an amputated limb. Other thought-controlled limbs are usually made by making a direct connection to the brain.
Those muscle-embedded electrodes pick up on signals sent from the brain to the muscles before translating those signals into movement. As Gizmodo notes, those brain signals are often responsible for the phantom limb effect - the sensation of having a limb after it has been amputated.
DARPA released two videos showing off advances in prosthetic technology. The first demonstrates the progress of targeted muscle re-innervation (TMR)
A veteran who lost his right arm in Iraq demonstrated how far TMR has come along by drinking from a cup of coffee, picking up bouncing a tennis ball and catching a piece of cloth with DARPA's Reliable Neural-Interface Technology (RENET) program. Those actions, seemingly simple at first glance, are fairly complicated maneuvers, requiring simultaneous joint control of the arm and hand.
The second video demonstrates the progress made by researchers at Case Western Reserve University under the RE-NET program. The video shows a man rummaging behind a curtain for small cubes to place on the side, requiring him to feel for the objects. That's because the university's advancement uses a falt interface nerve electrode (FINE) which gives amputees sensory feedback through the user's fake limb. That development allows amputees to feel for objects - say coins in a pocket - without having to use their eyes to guide their limb.
But while the advanced prosthetic limbs are neat, they're still a ways off according to DARPA officials.
"Although the current generation of brain, or cortical, interfaces have been used to control many degrees of freedom in an advanced prosthesis, researchers are still working on improving their long-term viability and performance," Jack Judy, DARPA program manager said in a press release. "As the RE-NET program continues, we expect that the limb-control and sensory-feedback capabilities of peripheral-interface technologies will increase and that they will become even more widely available in the future."
