A paralyzed man was able to walk again after communication was restored between his brain and spinal cord using a wireless ‘digital bridge’.
The brain-computer interface is made up of two electronic implants, one in the brain and one in the spinal cord.
Learn more:
Analysis: Paralysis breakthrough is pretty amazing – and AI is key
The first is placed over the region of the brain responsible for controlling leg movements and can decode the electrical signals generated when we think about walking.
Similarly, the other implant is positioned on the part of the spinal cord that controls the legs.
Working together, the scientists say the breakthrough technology “transforms thought into action” – repairing the broken connection between the brain and the region of the spinal cord that controls movement.
The first patient was 40-year-old Dutch engineer Gert-Jan Oskam, who suffered a spinal cord injury in a bicycle accident while working in China in 2011.
It had left him paralyzed, but he noticed improvements within days of surgeons sizing the implants.
Rediscover simple pleasures
“I think the most surprising thing happened after two days,” Mr. Oskam said.
“Within five to a few minutes, I could control my hips.”
Since then, after “a long journey” of training, the patient is able to walk, climb stairs and navigate ramps.
He also rediscovered the “simple pleasure” of meeting friends in a bar.
The implants remained effective after a year, including when Mr. Oskam was unattended at home.
He was treated by neuroscientists and neurosurgeons from the Swiss University Hospital of Lausanne and the University of Lausanne, as well as the Federal Polytechnic School of Lausanne.
The implants themselves were developed by the Atomic Energy Commission.
How does the technology work?
Guillaume Charvet, project leader at the commission, said the implants use “adaptive artificial intelligence” to decode the brain’s movement intentions in real time.
Once the AI identifies the relevant signals, they are converted into spinal cord electrical stimulation sequences, which activate the leg muscles and cause the desired movement.
Remarkably, the patient experienced improvements in his sensory perceptions and motor skills which were maintained even when the digital bridge was turned off – enabling him to walk with crutches.
Professor Grégoire Courtine said this suggests the digital bridge has not only repaired the human spinal cord but is also “promoting the growth of new nerve connections”.
Mr Oskam is the only patient the digital bridge has been tested on, but it is hoped the technology can be used to restore arm and hand function in the future.
It could also be applied following other causes of paralysis, such as a stroke.
The results were detailed in the journal Nature.
