Gert-Jan Oscum was living in China in 2011 when he was in a motorcycle accident that left him paralyzed from the hips down. Now, with a combination of tools, scientists have given him control of his lower body again.
“For 12 years I’ve been trying to get back on my feet,” Mr Oscum said at a press conference on Tuesday. “Now I have learned to walk normal, natural.”
one in Study Published on Wednesday in the journal Nature, researchers from Switzerland described implants that provided a “digital bridge” between Mr Oscum’s brain and his spinal cord, bypassing the injured sections. The discovery allowed Mr Oscum, 40, to stand, walk and climb steep ramps with only the aid of a walker. More than a year after the implant was inserted, he has retained these abilities and has actually shown signs of neurological recovery, walking with crutches even when the implant is off.
“We took Gert-Jan’s ideas, and translated these ideas into spinal cord stimulation to re-establish voluntary movement,” says Grégoire, a spine specialist at the Swiss Federal Institute of Technology, Lausanne. Courtine, who helped lead the research, said at the press briefing.
Jocelyn Bloch, a neuroscientist at the University of Lausanne who placed the implant in Mr Oscum, said: “Initially it was quite science fiction for me, but today it became reality.”
In recent decades there have been many advances in technical spinal cord injury treatment. In 2016, a group of scientists led by Dr. Courtine was able to restore it walking ability in paralyzed monkeys, and another helped a man regain control with his crippled hand. In 2018, a different group of scientists, led by Dr. Courtine, found a way stimulate the brain With an electric-pulse generator, allows partially paralyzed people to walk and cycle again. Last year, more advanced Brain stimulation procedures allowed paralyzed individuals to swim, walk, and cycle within a day of treatment.
Mr. Oscum had gone through stimulation procedures in previous years, and even regained some ability to walk, but his improvement eventually stabilized. At the press briefing, Mr Oscum said these stimulation techniques had made him feel that there was something different about the motion, an alien distance between his mind and body.
The new interface changed this, he said: “Earlier the excitement was controlling me, and now I’m controlling the excitement.”
In the new study, the brain-spine interface, as the researchers said, took advantage of artificial intelligence thought decoder To read Mr Oscum’s intentions – detectable as electrical signals in his brain – and match them to muscle movements. From thought to action, the cause of natural motion was preserved. The only addition, as Dr. Courtine described, there were digital bridges spanning the injured parts of the spine.
Andrew Jackson, a neuroscientist at Newcastle University who was not involved in the study, said: “It raises interesting questions about the source of autonomy and commands. You are continuing to blur the philosophical boundary between what’s the brain and what’s the technology.” .
Dr Jackson said scientists in the field had been theorizing about connecting spinal cord stimulators to the brain for decades, but this marks the first time they have achieved such success in a human patient. He said, ‘Easy to say, very difficult to do.
To obtain this result, the researchers first implanted electrodes into Mr Oscum’s skull and spine. The team then used a machine-learning program to see which parts of the brain lit up when it tried to move different parts of its body. The idea was the decoder was able to match the activity of certain electrodes with particular intentions: one configuration lit up whenever Mr. Oscum tried to move his ankles, while one configuration lit up when he tried to move his hips.
The researchers then used another algorithm to link the brain implant to the spinal implant, which was set to send electrical signals to different parts of his body, triggering the movement. The algorithm was able to account for slight changes in the direction and speed of each muscle contraction and relaxation. And, because signals between the brain and spinal cord were sent every 300 milliseconds, Oscum could quickly adjust his strategy based on what was working and what wasn’t. He was able to flex his hip muscles within the first treatment session.
Over the next few months, the researchers fine-tuned the brain-spinal cord interface to better fit basic actions such as walking and standing. Mr. Oscum regained a somewhat healthy-looking gait and was able to climb steps and ramps relatively easily, even after months without treatment. Furthermore, after a year of treatment, they began to notice clear improvements in their movement without the aid of a brain-spinal cord interface. The researchers documented these improvements in tests of weight-lifting, balance and walking.
Now, Mr. Oscum can walk a limited path around his house, commute to a car and stop for a drink once in a while. For the first time, he said, he felt like he was in control.
The researchers acknowledged limitations in their work. It is difficult to distinguish subtle intentions in the brain, and although the current brain–spinal cord interface is suitable for walking, the same probably cannot be said for restoring upper body movement. Treatment is also invasive, requiring multiple surgeries and hours of physical therapy. Current systems do not cure all spinal palsy.
But the team was hopeful that further advances would make the treatment more accessible and more systemically effective. “It is our real objective,” said Dr. Courtin, “to make this technology available to all the patients around the world who need it.”