Quadriplegic regains movement via brain signals

An Ohio man with quadriplegia has used his own hands to pick up a bottle, swipe a credit card and play a video game with the help of technology that routes signals from his brain to his muscles, researchers reported in a study Wednesday.

Other paralyzed people have used their brain signals to command computers and robotic arms. But this “marks the first time a person living with paralysis has regained movement by using signals recorded from within the brain,” study co-author Chad Bouton of the Feinstein Institute of Medical Research told reporters Tuesday. The study appears in this week’s Nature.

“The first time when I was able to open and close my hand, it really gave me that sense of hope again,” said study participant Ian Burkhart, 24, who broke his neck diving into the ocean six years ago. “If — or when — I can use this system outside the clinical setting, it will really increase my quality of life.”

Other researchers, though, do not see the advance as a major breakthrough, and the study’s authors say it’s hard to predict when the technology will be ready for market.

Certainly some parts of the prototype system aren’t very user-friendly. To prepare Burkhart for the research, surgeons implanted nearly 100 electrodes in a region of his brain that would ordinarily command his right hand and fingers. It took immense “trial and error,” Burkhart said in a separate interview, for him to learn the thought pattern for controlling his hand.

When Burkhart thinks about something like making a fist, the electrodes pick up the changes in his brain cells and send signals through a cable protruding from his skull to an external computer and other gear. The machines process the data before handing it off to a flexible cuff wrapped around Burkhart’s forearm. The cuff’s electrodes signal Burkhart’s muscles, sparking them into action.

Burkhart still has some use of his biceps and shoulder, allowing him to drive his wheelchair on his own and making it easier to perform some of the tasks he learned in the lab. He can pour the contents of a bottle into a jar, hold a phone to his ear and play a guitar-simulation video game.

Scientists who didn’t take part in the research were lukewarm about the new system.

The research team “did a fine job,” said Robert Kirsch of the Department of Veterans Affairs. “It just isn’t going to translate to a lot of people.” He thinks people with paralysis will shy away from brain surgery, and he says the system his own team developed years ago also restores hand function without a brain implant.

The movements achieved by the new system are “rudimentary,” says the University of Pittsburgh’s Andrew Schwartz. “It looks cool, but there’s a lot more work to be done.”

The team behind the Nature paper says the technology offers more refined finger movements than other technologies, as well as the ability to put movements together to perform everyday tasks.

With the new system, study co-author David Friedenberg of Battelle says via email, “Ian gained wrist and hand function at a level that is meaningful for reducing his dependence on others to complete tasks of daily living. We are the first to demonstrate a system with such a significant functional improvement.”

Burkhart himself needs no convincing. The abilities he’s regained in the lab would help him feed himself and brush his own teeth, so “if I could take it home and use it,” he said, “I would do it in a heartbeat.”