Researchers harnessed the Brain waves of a paralyzed man unable to speak and turned what he intended to say into sentences on a computer screen. It will take years of additional research but the study, reported Wednesday, marks an important step toward one day restoring more natural communication for people who can’t talk because of injury or illness.People who can’t speak or write because of paralysis have very limited ways of communicating. For example, the man in the experiment, who was not identified to protect his privacy, uses a pointer attached to a baseball cap that lets him move his head to touch words or letters on a screen. Other devices can pick up patients’ eye movements.
Tapping signals to work around a disability is a hot field. In recent years, experiments with mind-controlled prosthetics have allowed paralyzed people to shake hands or take a drink using a robotic arm they imagine moving and those signals are relayed through a computer to the artificial limb.Chang’s team built on that work to develop a speech neuroprosthetic decoding Brain waves that normally control the vocal tract, the tiny muscle movements of the lips, jaw, tongue and larynx that form each consonant and vowel.
Chang’s lab has spent years mapping the Brain activity that leads to speech. The researchers temporarily placed electrodes in the Brain of volunteers undergoing surgery for epilepsy, so they could match Brain activity to spoken words. The next steps include ways to improve the device’s speed, accuracy and vocabulary size and maybe one day allow a computer-generated voice rather than text on a screen while testing a small number of additional volunteers