A man paralyzed from the chest down after a swimming accident has regained the ability to feed himself and drink from a cup, thanks to a brain implant that bypasses his spinal cord injury. Keith Thomas, 48, from Massapequa, New York, could not lift his arms off his wheelchair when he joined a clinical trial in 2021. After surgery to implant electrodes in his brain and months of training, he can now move his arms and hands and feel the sensation of touch.
Double Neural Bypass Restores Movement and Sensation
Researchers at the Feinstein Institutes for Medical Research developed a brain-computer interface that detects when Thomas wants to move his arms. The signals are routed to his arms and hands, while pressure sensors on his hand, fingers, and thumb send signals back to his brain to simulate touch. This 'double neural bypass' allowed Thomas to handle delicate objects like eggshells and feel his sister’s hand and his pet dog’s fur.
Remarkably, the technology appears to have partly rewired Thomas’s nervous system, restoring some hand functions and sensations that persist even when the system is switched off. 'For me this is an incredible moment,' said Prof Chad Bouton, who led the development. 'For years, we have been wanting to really tackle the restoration of movement and the sense of touch and bring those together and we’ve also wanted to create lasting effects.'
Clinical Trial Results Show Significant Improvements
Thomas broke his neck diving into a swimming pool in July 2020 at age 42. He joined a three-year clinical trial in October of that year. After 35 weeks of training, his right arm strength increased by 86% and his left arm by 62%. He could independently scratch his nose and wipe his face, tasks he could not perform at the trial’s start.
The researchers also used a technique called cortical mirroring to enhance Thomas’s sense of touch. They recorded his brain activity while he imagined being touched, then stimulated sensory brain regions with the same patterns while simultaneously stimulating his skin and spinal cord. After 25 weeks of therapy targeting his right wrist, Thomas regained touch in an area that had been numb since his accident.
Long-Term Gains and Future Potential
In a follow-up after more than two years, the improvements were still present. 'This is incredibly encouraging,' said Bouton. The technology could potentially help millions of people with paralysis, but more trials are needed to determine its effectiveness for different spinal cord injuries.
Writing in Nature Medicine, the researchers described Thomas’s progress and the potential for lasting neural rewiring. 'I think we’re going to continue to see progress and I think it’ll be applicable to the millions of folks around the world who really need this technology,' Bouton added.
