WASHINGTON: In a world first, US researchers have developed a neuroprosthetic device that successfully translated the brain waves of a paralyzed man into complete sentences, according to a scientific paper published Thursday. “This is an important technological milestone for a person who cannot communicate naturally,” said David Moses, a postdoctoral engineer at the University of California San Francisco (UCSF), and one of the lead authors of the study in the New England Journal of Medicine. “It demonstrates the potential for this approach to give a voice to people with severe paralysis and speech loss. ” The breakthrough involved a 36-year-old man who had a stroke when he was 20 that left him with anarthria — the inability to speak intelligibly, though his cognitive function had remained intact. Every year, thousands of people lose the ability to talk due to strokes, accidents or disease. Past research in this area has focused on reading brain waves via electrodes to develop mobility prosthetics that allow users to spell out letters. The new approach was intended to enable more rapid and organic communication. UCSF researchers had previously placed electrode arrays on patients with normal speech who were undergoing brain surgery, to decode the signals that control the vocal tract in order to express vowels and consonants, and were able to analyze the patterns to predict words. But the concept hadn”t been tried out on a paralyzed patient to prove it could offer clinical benefit.