A brain-computer interface (BCI) that translates electrical signals detected from the scalp into a user's commands offers comparable precision, speed and accuracy to systems that rely on electrodes surgically implanted in the brain, researchers at the Department of Health's Wadsworth Center laboratories have shown.
It has been widely assumed that only invasive devices could control complex movements, such as operating a word processing program or a motorized wheelchair by thought alone.
Jonathan Wolpaw, M.D., and Dennis McFarland, Ph.D., published their findings online in the Proceedings of the National Academy of Sciences the week of December 6, 2004. The paper will appear in the journal's December 21, 2004, print edition. Dr. Wolpaw's laboratory pioneered BCI technology.
BCIs provide an alternative communication and control option for the severely disabled, such as individuals with Lou Gehrig's disease, brain and spinal injuries, cerebral palsy and other neurodegenerative diseases. The brain's electrical output is translated by a computer into physical outputs, such as moving a cursor on a computer screen.
In the Wadsworth system, users wear an electrode cap that detects electroencephalographic (EEG) activity from the scalp and records specific brain waves. An adaptive algorithm analyzes the output and focuses on the signals that provide people greatest control as they learn to use their thoughts to direct a cursor to a target on a computer screen. As the trainee improves, the algorithm adapts anew.
"Thanks to medical technology, people paralyzed by brain injuries or disorders are living longer. Brain-computer interface technology promises to improve their quality of life by offering a new chance to communicate and control their lives," said Commissioner of Health Antonia C. Novello, M.D., M.P.H., Dr.P.H.