A team of scientists at the University of California have created a brain-computer interface (BCI) that is capable of restoring a form of speech for a man suffering from amyotrophic lateral sclerosis (ALS), or Lou Gehrig's disease.
The 45-year-old man named Casey Harrel suffers from ALS, which causes a loss of muscle control that can severely impact the clarity of speech. Harrel is now able to communicate his thoughts through the BCI, which converts his brain signals into words that are then "read" by the computer and spoken out loud in real time. Moreover, Harrel's BCI is designed to sound like his own voice before the disease influence how it sounded.
How does it work? The BCI was implanted into the region of the brain that is responsible for speech, and with its 256 electrodes, it is capable of analyzing brain activity sent to that region of the brain and then converting it into readable data for the computer to interpret. More specifically, the BCI converts brain activity into what is called a "phoneme" or a "syllable or the unit of speech."
"Previous speech BCI systems had frequent word errors. This made it difficult for the user to be understood consistently and was a barrier to communication. Our objective was to develop a system that empowered someone to be understood whenever they wanted to speak," explained UC Davis neurosurgeon David Brandman, the principal investigator in the experiment and the co-senior author of the study published this week in the New England Journal of Medicine