Paralyzed man can feel objects through someone else’s hand

Keith Thomas was paralyzed from the chest down after a diving accident in 2020. He recently began feeling and moving his hand again. But it wasn’t yours.

Thanks to a pioneering experiment conducted by researchers at the Feinstein Institutes for Medical Research, in New York, the North American in his 40s was able to control and feel another person’s hand as if it were his own, through a system of brain implants linked by artificial intelligence.

“We created a mind-body connection between two different individuals”, explained the person responsible for the study, Chad Boutoncited by . The researcher believes that this technology could, in the future, transform the rehabilitation of people with spinal cord injuries and even allow humans to share sensations from a distance.

The process began in 2023, when the team implanted five sets of tiny electrodes into the areas of Keith Thomas’s brain responsible for movement and tactile sensation in his right hand. These brain signals were deciphered by an artificial intelligence model and sent wirelessly to electrodes placed on the forearm, which stimulated the muscles, allowing him to move his hand.

Simultaneously, force sensors placed on the skin returned impulses to the brain, recreating the sensation of touch.

Scientists then connected Thomas’ system to the body of an able-bodied woman. She wore sensors and electrodes on her hand, but remained motionless. By imagining that he was moving his own hand, Thomas was able to open and close the woman’s hand. And he was also able to feel, in his own brain, the textures and pressure of the objects touched by that other hand, such as a baseball, a soft foam ball and a harder one, reports the case study, September 22 on medRxiv.

Blindfolded, the patient was able to distinguish between objects with an accuracy of 64%. Although still far from perfect, Bouton believes the technology can be improved with more sensors and electrodes.

In another trial, Thomas used the system to help a partially paralyzed woman, Kathy Denapoli, hold and drink from a can — something she couldn’t do on her own. After months of collaboration, Denapoli regained almost twice the strength in his hand, progress superior to that of conventional therapies, according to Bouton.

“It was incredible, I was helping someone just by thinking about it,” Thomas said.

The lead researcher plans to expand testing to more people next year, but recognizes the ethical challenges of the technology.

“Is it good or bad for society to allow someone to feel and control someone else’s body?” asks Harith Akram, from University College London Hospitals.