Early on the afternoon of April 1, Adam Wilson posted a message to Twitter. But instead of using his hands to type, the University of Wisconsin biomedical engineer used his brain. "USING EEG TO SEND TWEET," he thought.

That message may be a modern equivalent of Alexander Graham Bell's "Mr. Watson, come here. I want to see you." Brain-computer interfaces are no longer just a gee-whiz technology, but a platform for researchers interested in immediate real-world applications for people who can think, but can't move.

"We're more interested in the applications," said Justin Williams, head of the University of Wisconsin's Neural Interfaces lab. "How do we actually make these technologies useful for people with disabilities?"

The researchers built upon the BCI2000, a software tool pioneered by Williams and Wadsworth Center neural injury specialist Gerwin Schalk. The software translates thought-induced changes in a scalp's electrical fields to control an on-screen cursor.

The BCI2000 is already used by 120 laboratories worldwide, but its communications applications have been largely restricted to messages appearing on a nearby screen.

"A lot of these have been scientific exercises, geared to writing things out but not really doing anything with it," said Williams. "We wanted to say, that's not how a person would want to communicate, especially with the advent of online communications."

The work is special because it meets the immediate needs of locked-in people, said Purdue University biomedical engineer Kevin Otto, who was not involved in the project.

"It's in tune with what patients want," said Otto. "Social networking and communication is really their first desire. There's been quite a bit of success, and a few demonstrations, helping people to e-mail. But the same reason why people choose Twitter and Facebook over e-mail is the same reason why this is significant."

Williams described e-mail as a a relatively difficult and inefficient task for someone on a brain-computer interface.

"It's difficult enough to be able to spell words, much less find an address book and select names. The overhead involved in these applications is just too much," he said. "Twitter is very serendipitous. It handles all the things that we've been struggling to make easy for a patient to do. It puts messages where people can find them. Let the world know how you're doing, what you're thinking, and they'll find you. And that's perfect for these patients and their families."

Wilson will soon install their program in the homes of

10 people already outfitted with trial versions of the BCI2000. That system is not yet commercially available, but that day could come soon.

"It's at the point where it's beyond proof of concept," Wilson said. "We know it works. The next question is how to integrate it into people's homes, so that a caretaker could set it up without need for outside help."

Other brain-computer interfaces may someday help people control robotic prostheses, even body-sheathing exoskeletons that return a user's body to functionality.

"Those are going to be great applications in the future, but at the same time we need to see what BCIs can do right now," said Williams.

Wilson's later brain-to-Twitter messages included "GO BADGERS" and "SPELLING WITH MY BRAIN."

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Video: YouTube/University of Wisconsin

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