National Geographic : 2014 Feb
56 national geographic • February 2014 “Cathy’s smile when she put down that drink— that’s everything,” Donoghue says. Today Donoghue and other scientists are building on that success, hoping to create human-machine interfaces that will be power- ful, safe, and easy. At Duke University Miguel Nicolelis has been experimenting with exoskel- etons that strap on to the body. Signals from the brain control each limb. Already he has gotten monkeys to control full-body exoskeletons. If all goes well, a paraplegic wearing a simpler version of the device will deliver the open- ing kick at the 2014 World Cup in Nicolelis’s native Brazil. “Eventually brain implants will become as common as heart implants,” says Nicolelis. “I have no doubt about that.” When it comes to the brain, predicting the fu- ture is a tricky game. Advances in the past have inspired giddy expectations that in many cases have not been met. “We can’t tell a schizophren- ic brain from an autistic brain from a normal brain,” says Christof Koch. But the research that’s going on now, he believes, is moving neurosci- ence to a remarkable new stage. “I think we can begin to put the pieces together.” j the computers to recognize signals in her motor cortex and use them to move a computer cursor around a screen. This was achieved the first time she tried because they had learned how to trans- late patterns of brain activity into movements. Two years later they coupled a robotic arm to the computers, refining a program that could inter- pret Hutchinson’s brain signals to move the arm forward and back, to raise it up and down, and to open its robotic fingers and squeeze them shut. After just a few sessions Hutchinson, the com- puter, and the robotic arm had become a team. “It felt natural,” she tells me. So natural that one day she reached out for a cinnamon latte, grabbed it, and brought it to her lips to drink. By thought alone A rhesus macaque walks with the aid of a pneumatically powered exoskeleton controlled by a computer reading signals from electrodes implanted in the monkey’s motor cortex. Miguel Nicolelis and colleagues at Duke University are developing similar devices that could allow paralyzed humans to walk again.