Wednesday, December 30, 2009

NY researchers show brain waves can be used to type messages on computer screen

From The Business Review in Albany, N.Y.:

Researchers at Albany Medical College have demonstrated an experimental technology that allows people to use brain waves to spell out messages on a computer screen at a faster rate than allowed by other devices.

The findings are part of an ongoing research effort in brain-computer interface (BCI) at the Albany, N.Y., medical school. They were presented earlier this month at the 63rd meeting of the American Epilepsy Society in Boston.

The goal of a BCI system is to allow people—such as those severely paralyzed or “locked in” by amyotrophic lateral sclerosis (ALS), brainstem stroke, severe cerebral palsy or other disorders—to use their brain signals to communicate or manipulate their environment. Past studies have used electroencephalography (EEG)—the recording of electrical activity from electrodes placed on the scalp. The Albany Med method read brainwaves using electrodes placed on the surface of the brain.

“Spelling rates were up to three times faster when compared to using signals from the scalp,” said Dr. Anthony Ritaccio, director of the Epilepsy and Human Brain Mapping Program at Albany Med. “The subject in this study was able to spell with her mind faster than some people can type.”

In the Albany Med study, the subject looked at a monitor that displayed a 6x6 matrix containing alphabetic and numeric characters, and space and backspace commands. Each row and column of the matrix was illuminated randomly and rapidly, at a rate of 16 times per second. The subject’s task was to pay attention to each of the characters she wanted to spell. The computer learned the desired character by interpreting and recording the brain’s responses to the illuminated row and column that commonly contained the desired character.

The subject was able to make character selections at rates of more than 20 characters per minute at or close to 100 percent accuracy.

“These results could further extend communication options, such as e-mail or instant messaging, for people with severe motor disabilities to connect with the outside world,” said Dr. Ritaccio.

Joining Dr. Ritaccio in leading the research team was Dr. Gerwin Schalk, associate professor of neurology at Albany Medical College and research scientist at the Wadsworth Center of the state Department of Health. Over the past decade at Wadsworth, Dr. Schalk has led an international effort to develop a general-purpose software platform for BCIs and brain monitoring. This software is becoming the standard software for BCI research in hundreds of labs around the world.