NEW YORK • Six years after being paralysed from the chest down, an American man can use his right hand to stir coffee and swipe a credit card, a ground-breaking study reported on Wednesday.
The unprecedented feat was made possible by using computer software to replace the damaged spinal cord as the communication highway between Mr Ian Burkhart's brain and his hand muscles.
"This is the first time that a completely paralysed person has regained movement just by using their own thoughts," said researcher Chad Bouton of the Feinstein Institute for Medical Research in Manhasset, New York.
Mr Burkhart, a 24-year-old from Ohio, has a pea-sized chip in his head that reads his brain signals, which are then deciphered by a computer and rerouted to his hand, wrist and finger muscles.
The muscles receive their instructions from an electrode sleeve worn on his right forearm - now, Mr Burkhart can also use them to swipe a credit card, pick up a spoon, hold a telephone to his ear and play the chords on a guitar video game.
The United States-based researchers hope their work, still in an early phase, will one day help paralysed people feed and dress themselves.
Mr Burkhart broke his neck during a holiday diving accident when he was 19 and was left quadriplegic - meaning his arms and legs are paralysed.
"Doctors told me I'd broken my neck and, most likely, I'd be able to move my shoulders around, but nothing else for the rest of my life," he told journalists at a teleconference ahead of the report's release.
He was left paralysed from the chest down, but still has some movement in his shoulders and biceps.
He volunteered for the trial, he said, because he wanted to help people like himself regain their independence.
"Just not being able to use your hands does limit you quite a bit," he said. "I have to rely on other people for things."
He underwent surgery to have the chip implanted in the brain's motor cortex area, which controls movement.
The chip was attached on top of the skull to a "connector" linking it to a computer, which Mr Burkhart "trained" to read his mind and decode which movements he wanted to execute.
"When we first hooked everything up... it was a big shot," he recounted. "I hadn't moved in about 31/2 years at that point."
"Now, it's something that's just so fluid, it's kind of like it was before I had my injury," he said.
The new technology is not a cure for paralysis: Mr Burkhart could use his hand only when connected to computers in the lab, and the researchers said there was much work to do before the system could provide significant mobile independence.
They hope to improve the technology to help not only people with spinal cord injuries, but also those who had suffered a stroke or a traumatic brain injury.
AGENCE FRANCE-PRESSE, NEW YORK TIMES