In a first, scientists have created a system that translates thoughts into intelligible, recognizable speech, an advance that may help people who cannot speak regain their ability to communicate with the outside world.
By monitoring someone’s brain activity, the technology developed by researchers from Columbia University in the US can reconstruct the words a person hears with unprecedented clarity. It also lays the groundwork for helping people who cannot speak, such as those living with as amyotrophic lateral sclerosis (ALS) or recovering from a stroke, regain their ability to communicate with the outside world.
The breakthrough harnesses the power of speech synthesizers and artificial intelligence, could lead to new ways for computers to communicate directly with the brain. Decades of research has shown that when people speak—or even imagine speaking—telltale patterns of activity appear in their brain.
The distinct pattern of signals also emerge when we listen to someone speak, or imagine listening. Experts, trying to record and decode these patterns, see a future in which thoughts need not remain hidden inside the brain — but instead could be translated into verbal speech at will.
Researchers plan to test more complicated words and sentences next, and they want to run the same tests on brain signals emitted when a person speaks or imagines speaking. However, because this approach has failed to produce anything resembling intelligible speech, the team turned instead to a vocoder, a computer algorithm that can synthesize speech after being trained on recordings of people talking.