April 20, 2009 at 10:55 PM ET
Click for video: University of Wisconsin researcher Adam Wilson composes
a Twitter message using a system that reads his brain waves. Click on the
image to watch a video explaining how the message was sent.
"GO BADGERS" isn't an unusual message to get from the University of Wisconsin at Madison - particularly when it's a status update from Twitter, the texting service that limits users to 140 characters at a time.
The unusual thing about this message is how it got to Twitter in the first place: via brain waves.
University of Wisconsin doctoral student Adam Wilson's cheer for the hometown team is among the first direct brain-to-Twitter messages ever sent - and it points the way to better communication systems for paralyzed patients who have to cope with the conditions faced by physicist Stephen Hawking and the late Jean-Dominique Bauby, author of "The Diving Bell and the Butterfly."
Wilson suffers no such disability - but he put on the electrode-equipped cap and sent out Twitter updates with his thoughts in order to test out the system. "SPELLING WITH MY BRAIN," he says in one of the messages.
The first step in the process involves looking at an array of characters that flash on a computer screen.
"All the letters come up, and each one of them flashes individually," Justin Williams, a UW assistant professor of biomedical engineering who serves as Wilson's faculty adviser, explained in a news release issued today. "And what your brain does is, if you're looking at the 'R' on the screen and all the other letters are flashing, nothing happens. But when the 'R' flashes, your brain says, 'Hey, wait a minute. Something's different about what I was just paying attention to.' And you see a momentary change in brain activity."
The electrodes embedded in the cap read that change and figure out which character is associated with it - although sometimes it takes a few repeats to get the letter absolutely right. "Some people, for whatever reason, are better at this," Williams told me today. "They have stronger brain signals for the given activity."
Users can pick up the pace with practice: "I've seen some people do up to eight characters per minute," Wilson said.
One by one, the letters add up on the computer screen. When the message is complete, Wilson concentrates on the "Twit" box on the screen. The software then sends out Wilson's message to the Twitter service. Anyone who has signed up to "follow" Wilson's updates gets the message instantly, via computer or cell phone.
Unlocking 'locked-in' patients
Williams said his research group has been working on communication tools for people who suffer from "locked-in syndrome" - a neurological condition, often associated with stroke, that almost completely paralyzes the body while leaving the mind intact.
Experts estimate that 25,000 to 50,000 patients in the U.S. have the condition. Such patients can't use the mouth- or eye-controlled systems often employed by quadriplegic patients. Typically, they can communicate only by blinking their eyes in code. (Stephen Hawking, who has a progressively worsening case of amyotrophic lateral sclerosis, has most recently been using a communication system that responds to twitches in his cheek muscles.)
The system to replace eye-blinking with brain-wave readings was developed by Williams and Wilson in collaboration with Gerwin Schalk and colleagues at the Wadsworth Center in Albany, N.Y.
"Our group has been trying to do things via e-mail or more standard messaging, but that's not really well-suited," Williams said. Locked-in patients "don't necessarily have the capacity to write out complex e-mails, or to pick out the groups of people to send them to," he explained.
"When we talk to these people," Williams said, "the things they want to do is send simple messages to the people who are thinking of them." The message might be as simple as saying that they're doing OK today, or that they need someone to come by.
Twitter to the rescue
That makes Twitter "the perfect application" for the system, Williams said. Patients can send a simple message to everyone who wants to know how they're doing - and can keep track of everyone they're following.
"This is one of the first - and perhaps - most useful - integrations of brain-computer interface technologies with Internet technologies to date," the Wadsworth Center's Schalk said in today's news release.
Researchers at the Wadsworth Center and the University of Tubingen in Germany plan to begin in-home trials of the system with locked-in patients later this year.
"It could be a very enabling technology for those patients," Williams told me, "because it gives them an opportunity to interface with the electronic world where someone on the other end wouldn't necessarily know that they're disabled."
The ideal would be to develop an inexpensive system that would allow the user to communicate through a wired baseball cap that's hooked up to a home computer system. A somewhat more intrusive system, which would involve implanting electrodes just under the skin, could significantly improve the pace of communication, Williams said.
However, Williams can't yet predict how much a practical brain-wave communication system might cost, or when it might become commercially available. "We're not really in that business, but it would be great if somebody were interested in that," he said.
And that's another reason why Williams and his fellow researchers were so attracted to the idea of Twittering with the brain. "Since Twitter is very popular, certainly among younger-age people, this will help convince people that science and engineering careers can have some impact on the way people live," Williams said.
Funding for the research was provided by the National Institutes of Health, the UW-Madison Institute for Clinical and Translational Research, the UW-Madison W.H. Coulter Translational Research Partnership in Biomedical Engineering and the Wisconsin Alumni Research Foundation.