Doctors couldn’t fix Ian Burkhart’s spinal cord injury. So engineers figured out a way around it.
Their “neural bypass” system uses a brain implant to record the electrical signals generated when Burkhart tries to move one of his paralyzed hands. Those signals are decoded by a computer and routed to an electronic sleeve that stimulates Burkhart’s forearm muscles in precise patterns. The result looks surprisingly simple and natural: When Burkhart thinks about picking up a bottle, he picks up the bottle. When he thinks about playing a chord in Guitar Hero, he plays the chord.
Yet the technology at work is far from simple. The achievement, reported today in Nature, caps a decade of research on brain-computer interfaces (BCIs) for paralyzed people. In 2006, a quadriplegic man used a brain implant to control the movements of a computer cursor; six years later a quadriplegic woman used an implant to control a robotic arm, which she used to independently bring a coffee drink to her lips. Meanwhile, other researchers have investigated different ways to control paralyzed limbs with electricity, using stimulating electrodes to jolt muscles into action.
Today’s announcement marks the first time these two technologies have been combined to help one human. BCIs had previously shown progress “with cursor control, using a computer, being able to operate devices, and even prosthetic arms,” says Chad Bouton, a study coauthor who researches bioelectronic medicine at the Feinstein Institute on Long Island. “But no one had restored any movement to the arm. We decided to take it to that next level.”