By DON DODSON
© 2005 THE NEWS-GAZETTE
Published Online October 19, 2005

URBANA – University of Illinois graduates Mike Callahan and Thomas Coleman have come up with a new means of communication for those unable to speak.

Specifically, they've designed a system that detects what those people are trying to say. Their invention could make communication easier for people with spinal cord injuries or ALS (amyotrophic lateral sclerosis), commonly known as Lou Gehrig's disease.

Callahan started work on the idea as a junior and made it his senior design project. Now a grad student, he's working with Coleman to develop the technology for their newly formed company, Ambient. The Rehabilitation Institute of Chicago has agreed to test the system on patients.

The system uses an electrode inside a form-fitting band that attaches to the neck. The device applies gentle pressure on the vocal cords and detects "subvoiced" signals from the brain to the larynx. With repetition, the device can recognize whether a person's response is "yes" or "no" before the person even attempts to voice the word.

Callahan, 23, of Urbana explained that people with spinal cord injuries often lose function in their diaphragm and lack the ability to blow air through their lungs. As a result, they don't have enough force to create speech – but they do have the ability to "subvocalize."

Ambient's sensor picks up the signal from the brain at the larynx. Then, through signal processing, the system recognizes speech that is, in Callahan's words, "a step above pure thought."

Right now, the team is working on its fifth prototype, with each sensor smaller than the previous version. Callahan figures that by May 2007, the device should be "ready to add functionality to people's lives."

"This will be adding great benefit to life by giving them the ability to choose," he said.

Later, he hopes the product can move to "mainstream" markets, enabling people with normal voice function to carry on a conversation via cellphone – without speaking aloud. Theoretically, people on a crowded bus or train could use it without showing visible signs of communicating.

Callahan and Coleman incorporated their company, Ambient, this month, just two days before Callahan's birthday.

"My birthday was coming up, and I wanted to incorporate my first company when I was 22," Callahan said. "I want to be on my second company at 30, which gives me eight years on this."

Callahan said he was initially interested in electrical engineering and nanotechnology. He ended up majoring in general engineering and today is a graduate student working at the UI's Technology Entrepreneur Center.

At one point, he deliberated whether he should stay at Illinois or transfer to another graduate program. It took him only a few minutes to decide to stay and work on the project.

"I had a need to improve people's lives. That's the engineer in me," said Callahan, a vegetarian from Joliet who keeps a pet rabbit, Peekaboo, in his room.
Coleman teamed with Callahan on the senior design project, working on the device that picks up signals and turns them into an actual response. After graduation, Coleman moved to Joliet, but plans to move back to Champaign-Urbana later this year to work on the project.

Coleman, 23, said the best part is knowing the project can help people with readily identifiable problems.

"When you know this person could actually use our help, there's no motivation greater than that," he said.

Another student, UI senior David Osorio, teamed with Callahan to write a business plan for Ambient last year. The plan was a finalist in the UI's annual V. Dale Cozad Business Plan Competition.

"The biggest thing the project has going for it is Mike," Osorio said. "He's truly passionate about it and has made it part of his master's program. He knows how to work with people, and he's always had the mentorship of Professor Brian Lilly. ... He (Callahan) has a tremendous driving force in his heart for that project."

Lilly, a UI adjunct associate professor of general engineering, said he is impressed by Callahan's commitment.

"These things are happening because of his efforts. He's really self-motivated and self-educated in a lot of ways. A lot of things he had to learn were not from courses in school," he said.

Lilly said it's difficult to predict how Ambient will do.

"With any start-up, its a coin toss," he said. "(The Ambient system) can differentiate between 'yes' and 'no.' They probably have to do more than that to make it a valuable product, and I think they can. A lot of it is time frame. Product development takes a while, and students are usually up against a graduation date. ... A lot depends on what commitment they continue to make with it."