Paralysed man harnesses brain power to walk again with robot exoskeleton

Reuters - The French tetraplegic man who has been able to walk again using a pioneering four-limb robotic system, or exoskeleton, said walking was a major feat for him after being immobile for years. The French scientists behind the system, which was publicly unveiled last week, use a system of sensors implanted near the brain which sends signals to the robotic system, moving the patient's legs and arms. Speaking to media on Monday in the French city of Grenoble, the 30-year-old patient, who was identified only by his first name, Thibault, said he had to re-educate to use his brain when he started to try the whole-body exoskeleton. "As I hadn't moved for two years I had to re-learn to use my brain," he said. "It's something very complicated, because you have a leg that doesn't move, so it's trying to imagine a movement," he said, adding that he could do walking cycles for longer periods after training. In a two-year-long trial, two recording devices were implanted, one either side of Thibault's head between the brain and the skin, spanning the region of the brain that controls sensation and motor function. "We proposed something ambitious - which is to renew voluntary mobility and close to the real thing, meaning to take the information where they are stored, in each one of us, meaning in our brains," said neurosurgeon Alim Louis Benabid. Each recorder contained 64 electrodes that collected brain signals and transmitted them to a decoding algorithm. The system translated the brain signals into the movements the patient thought about and sent his commands to the exoskeleton. Over 24 months, the patient carried out various mental tasks to train the algorithm to understand his thoughts and to progressively increase the number of movements he could make. For now the exoskeleton is purely an experimental prototype.