A 48-year-old man paralyzed from the chest down has regained the ability to feed himself and feel touch sensations after a novel brain implant and training program effectively rewired his nervous system. Keith Thomas, of New York, suffered a broken neck in July 2020 after a diving accident, leaving him unable to move below the chest.
In October 2020, Thomas enrolled in a clinical trial where researchers implanted a computer chip into his brain. This device, combined with 35 weeks of specialized training, has allowed him to regain voluntary control over his arms and hands. His right arm strength has increased by 86%, and his left arm by 62%, enabling him to perform tasks like eating and drinking independently.
The system uses electrodes implanted in the brain to detect intended arm movements. These signals are then transmitted to a device that bypasses the spinal cord injury, stimulating the nerves and muscles to execute the movement. For the first time since his accident, Thomas can lift his arms, even when the implant is turned off. He can also feel the sensation of touch, which has been partially restored to his right wrist through a technique called cortical mirroring. Pressure sensors on his hands send signals back to the implant, stimulating the brain to create a sense of contact.
This restoration of both movement and sensation is a significant development, according to Professor Chad Bouton of the Feinstein Institutes for Medical Research, who led the study published in the journal Nature. "For me this is an incredible moment," Bouton stated. "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."
Follow-up assessments indicate that the functional and sensory gains have persisted for over two years after the initial implantation in 2021. Researchers are optimistic about the technology's potential, with Bouton adding, "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."
While Thomas's results are described as 'incredibly encouraging,' further research is required to determine the extent to which this brain-computer interface can benefit patients with other types of spinal cord injuries. Spinal cord injuries disrupt the transmission of electrical messages between the brain and the body, often leading to a loss of movement and sensation below the level of the injury.