Researchers at Duke Health, led by Miguel Nicolelis of the Walk Again Project, have developed a wireless cortical brain-machine interface (BMI) that allows monkeys to drive a robotic wheelchair using only their brainwaves.
Nicolelis and his team implanted multichannel microelectrode arrays in the brains of two rhesus monkeys, which wirelessly recorded electrical impulses generated by their brain cells.
Similar to a previous experiment, an algorithm was developed to interpret the patterns, determine the monkey’s intention, and send those commands from the brain directly to the wheelchair.
Overtime, results showed that the monkeys showed an improved ability to navigate the wheelchair toward the location of the reward, which in this case was a bowl of grapes.
According to Nicolelis, the data also indicates that “the wheelchair is being assimilated by the monkey’s brain as an extension of its bodily representation of itself.” In other words, the monkey started to think that the wheelchair is part of its body.
“We are not focused on the wheelchair—we’re actually developing robotic exoskeletons in parallel to this,” he said. “But in principle, it could be any kind of vehicle because this is a general purpose approach.”
Previous experiments only showed the potential of using BMIs to control bimanual arm movements, this latest study shows that it can go beyond that, and facilitate whole-body movement.
By restoring whole-body mobility, this technology can help even the most severely paralyzed patients only regain their ability to walk using a robotic exoskeleton, and through intense BMI training, they can also exhibit signs of partial neurological recovery.
“We’re going to go for it now,” he said. “We’re ready with the technology so we’re preparing to apply for human implants. We’re finally there after 17 years of research. I think we’re ready for it.”