Original URL: http://www.theregister.co.uk/2013/06/01/darpa_bionic_arm/

Finally – mind-controlled limbs without brain surgery

Neural-interface tech gives wounded soldier a hand (and arm)

By Jack Clark

Posted in Science, 1st June 2013 00:25 GMT

DARPA-backed research has given a wounded serviceman a fancy mind-controlled prosthesis without the need for brain surgery.

The bionic arm was developed by researchers at the Rehabiliation Institute of Chicago with financial backing from DARPA's reliable neural-interface technology (RE-NET) program, the US skunkworks lab announced on Thursday.

The tech gives the amputee, former army Staff Sergeant Glen Lehman, the ability to simultaneously control many joints in a prosthesis by thought, and does this without the need for brain surgery.

With the technology, he is able to pick up and drink a cup of coffee, drop and catch a tennis ball, and even intercept a falling piece of fabric.

He is able to do this via targeted muscle re-innervation, which reassigns nerves from a lost arm or hand to chest (pectoral) muscles. This works because when Lehman thinks of doing something with his arm, the nerve signals go from brain to his spinal cord, and then into the (transplanted) nerves on his chest, causing a slight contraction which sends an electrical signal to an antenna implanted on the chest, which then broadcasts to a reciever in the prosthesis. This makes it possible for him – and eventually others – to control their limbs with the power of their minds.

Watch Video

A further remarkable part of the RIC demonstration is the lack of bulky equipment. Previous tests meant subjects were either attached to power sources, or forced to wear bulky bits of equipment, as shown in this 2011 video.

RIC has been working on TMR for almost a decade, partly thanks to a major investment in neural prosthesis by DARPA. Last time El Reg discussed RIC, it had equipped a man with a bionic leg that helped him stride to the SkyDeck of Chicago's Willis Tower. Talk about giving someone a leg up!

TMR is getting a lot of RE-NET funding because it gets rid of the need for brain surgery – a priority, given the huge medical costs of fiddling with the densest and most power-efficient computer on the planet, AKA the human brain.

"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," DARPA program manager Jack Judy said.

"The novel peripheral interfaces developed under RE-NET are approaching the level of control demonstrated by cortical interfaces and have better biotic and abiotic performance and reliability. Because implanting them is a lower risk and less invasive procedure, peripheral interfaces offer greater potential than penetrating cortical electrodes for near-term treatment of amputees."

Other areas of DARPA-funded research include adding sensory feedback into limbs, so that amputees can have a faint sense of electrically mediated "touch". Also in the release, DARPA announced that researchers at Case Western Reserve University have used a flat-interface nerve electrode to deliver feedback to someone with an artifical arm.

Though RIC offers muscle re-innervation operations to the public, the bionic arm demonstrated in this DARPA-backed research is not yet available to everyone, but is being rolled out at various military rehabilation centers around the USA, DARPA said. ®