SAN FRANCISCO - In a once unimagined accomplishment, electrodes implanted in the man’s brain transmit signals to a computer that displays his words.
Dr. Eddie Chang, a neurosurgeon at the University of California, San Francisco Medical School helped Pancho, a man paralyzed since age 20, speak through an implant in his brain that connects to a computer program.Mike Kai Chen for The New York Times
He has not been able to speak since 2003, when he was paralyzed at age 20 by a severe stroke after a terrible car crash.
Now, in a scientific milestone, researchers have tapped into the speech areas of his brain — allowing him to produce comprehensible words and sentences simply by trying to say them. When the man, known by his nickname, Pancho, tries to speak, electrodes implanted in his brain transmit signals to a computer that displays his intended words on the screen.
His first recognizable sentence, researchers said, was, “My family is outside.”
The achievement, published on Wednesday in the New England Journal of Medicine, could eventually help many patients with conditions that steal their ability to talk.
“This is farther than we’ve ever imagined we could go,” said Melanie Fried-Oken, a professor of neurology and pediatrics at Oregon Health & Science University, who was not involved in the project.
Three years ago, when Pancho, now 38, agreed to work with neuroscience researchers, they were unsure if his brain had even retained the mechanisms for speech.
The team implanted a rectangular sheet of 128 electrodes, designed to detect signals from speech-related sensory and motor processes linked to the mouth, lips, jaw, tongue and larynx. In 50 sessions over 81 weeks, they connected the implant to a computer by a cable attached to a port in Pancho’s head, and asked him to try to say words from a list of 50 common ones he helped suggest, including “hungry,” “music” and “computer.”
As he did, electrodes transmitted signals through a form of artificial intelligence that tried to recognize the intended words.
In nearly half of the 9,000 times Pancho tried to say single words, the algorithm got it right. When he tried saying sentences written on the screen, it did even better.
After a recent session, observed by The New York Times, Pancho, wearing a black fedora over a white knit hat to cover the port, smiled and tilted his head slightly with the limited movement he has. In bursts of gravelly sound, he demonstrated a sentence composed of words in the study: “No, I am not thirsty.”