For Pat Bennett, 68, every spoken word is a struggle.
Bennett has amyotrophic lateral sclerosis (ALS), a degenerative disease that has disabled the nerve cells controlling her vocal and facial muscles. As a result, her attempts to speak sound like a series of grunts.
But in a lab at Stanford University, an experimental brain-computer interface is able to transform Bennett's thoughts into easily intelligible sentences, like, "I am thirsty," and "bring my glasses here."
The system is one of two described in the journal Nature that use a direct connection to the brain to restore speech to a person who has lost that ability. One of the systems even simulates the user's own voice and offers a talking avatar on a computer screen.