medicine
A brain implant let them speak and wave again
Speech or movement, never both. Until now.
Scientists at the University of California, San Francisco have built a brain implant that lets people with paralysis speak and gesture at the same time, controlling a digital avatar with their thoughts in real time. The work, published in Nature Neuroscience on September 14, involved two participants, one paralyzed by a stroke and the other living with ALS. Each had an iPhone-size device holding 253 electrodes placed on the brain's surface, where it can cover a wide area without penetrating the tissue. The team trained models to decode phrases like "hello" and "nice to meet you" alongside gestures such as clapping and waving. The participant who had a stroke hit 100 percent accuracy across three conversation tests. Co-author Samantha Brosler says the point is nuance. "Saying 'maybe' and nodding your head has a very different connotation than if you shake your head." She wants the next version to move fifteen joints in a single hand.
