Prosthetics and new therapies restore abilities to move, see, walk.
December 2012 By Rachel Ehrenberg Article from Science News
Outfitted with a bionic eye, arm, legs and fantastic ’70s hair, Steve Austin was a cyborg whose implants allowed him to recover stolen atomic weapons, fight aliens and protect cryptographers in distress. Finally, real life is starting to catch up with the Six Million Dollar Man. In one of this year’s bionic breakthroughs, a paralyzed woman carried out her own superhuman feat: Using an implanted brain chip, she controlled a robotic arm with her mind (SN: 6/16/12, p. 5). She used the arm to grasp a cuppa joe and take a long, satisfying sip of coffee through a straw, an act she hadn’t done on her own for nearly 15 years.
“We’re entering a really exciting area where we can develop all sorts of very complicated technologies that can actually have biomedical applications and improve the quality of life for people,” says bioengineer Grégoire Courtine of the Swiss Federal Institute of Technology in Lausanne. “It’s a revolution.”
After her groundbreaking sip, Cathy Hutchinson, who had been paralyzed years earlier by a stroke, smiled and then laughed. A roomful of scientists burst into applause.
This was a big year for prosthetic parts, both in and out of the lab. Athletes in London for the Paralympics and the Olympics sprinted on high-tech carbon blades and hurled javelins while balancing on the microprocessor-controlled C-Leg. People in wheelchairs used battery-powered robotic suits to keep their lower limbs in shape. A young man who lost his right leg in a motorcycle accident climbed the 103 flights of stairs in Chicago’s Willis Tower with a thought-controlled limb. That technology is still in development. But some bionic add-ons are starting to come out of the lab and into the clinic for the first time, though costs remain prohibitive for many potential users.
The brain-machine interface that allowed Hutchinson to direct a robotic arm (shown above) with her thoughts, called BrainGate, was created by building upon decades of studies. Monkey experiments in the 1960s, for example, first linked arm movements to the firing of particular neurons in the brain. In 2008 scientists reported that a thought-controlled prosthetic arm had allowed a monkey to feed itself.
Another new prosthetic may restore partial sight to people suffering from macular degeneration or retinitis pigmentosa (SN: 6/16/12, p. 12). In existing retinal prosthetics, already on the market in Europe, wiring and coils are implanted along with chips that get slipped into the back of the eyes. The new retinal implant, now being tested in rats, implants only slender photovoltaic chips that go beneath the retinas. The rest of the hardware is incorporated into high-tech goggles with a miniature video camera that sends information to a portable computer about the size of a smartphone. Lasers inside the goggle lenses then project the images into the eyes, where the photovoltaic chip sends signals along to the brain.
“Thinking back to papers from the 1960s, people were building and soldering simple devices by hand,” says James Loudin, a researcher at Stanford who was part of the retinal implant team. “Now 50 years later, it’s night and day.”
Work by Courtine and colleagues has hinted at a different kind of sci-fi–like future — one with no need for bionics. Their research showed the potential of restoring function to limbs without using prosthetics at all. Rats paralyzed by spinal cord injuries were able to walk, run and even climb stairs after weeks of treatment combining drugs and electric shocks to the spine with physical therapy on treadmills (SN: 6/30/12, p. 5). But it wasn’t just technology that made the feat possible; the research showed the importance of that intangible thing called motivation. The rats who learned to walk were the ones that really wanted it; those trained without a tempting treat never learned to walk.
“We motivated the rats with chocolate,” says Courtine. “That’s when the miracle happened.”
A microchip that impressive is still a long way off.