Potential benefits for numerous medical populations
Scientists have found a way to transform brain signals into spoken words and sentences.
A group of researchers from the University of California at San Francisco believes the approach could someday help people who have lost the ability to speak or gesture, according to a report in the journal Nature.
“Finding a way to restore speech is one of the great challenges in neurosciences,” says Dr. Leigh Hochberg, a professor of engineering at Brown University who wasn’t associated with the study. “This is a really exciting new contribution to the field.”
Currently, people who are paralyzed and can’t speak or gesture often rely on eye movements or a brain-controlled computer cursor to communicate. These methods allow them to spell out words one letter at a time.
“It’s not the most efficient way to communicate,” says Dr. Edward Chang, a neurosurgeon at UCSF and an author of the study.
Indeed, that approach allows a person to type fewer than 10 words a minute, compared with speaking about 150 words per minute with natural speech.
Scientists have been looking for a way to let paralyzed patients produce entire words and sentences as if they were talking. Studying volunteers with severe epilepsy, the researchers temporarily placed electrodes on their brain surfaces to locate the area causing seizures.
As the volunteers read sentences aloud, scientists recorded signals from the brain’s speech centers, which control muscles in the tongue, lips, jaw, and larynx.
Dr. Chang hopes to try the approach soon in patients who have lost the ability to speak. The National Institutes of Health’s BRAIN Initiative was the primary funder for the research.