“By implanting an electrode into the brain of a person with locked-in syndrome, scientists have demonstrated how to wirelessly transmit neural signals to a speech synthesizer. The “thought-to-speech” process takes about 50 milliseconds – the same amount of time for a non-paralyzed, neurologically intact person to speak their thoughts. The study marks the first successful demonstration of a permanently installed, wireless implant for real-time control of an external device.
“The results of our study show that a brain-machine interface (BMI) user can control sound output directly, rather than having to use a (relatively slow) typing process,” Guenther told PhysOrg.com.
In their study, the researchers tested the technology on a 26-year-old male who had a brain stem stroke at age 16. The brain stem stroke caused a lesion between the volunteer’s motor neurons that carry out actions and the rest of the brain; while his consciousness and cognitive abilities are intact, he is paralyzed except for slow vertical movement of the eyes. The rare condition is called locked-in syndrome.
Five years ago, when the volunteer was 21 years old, the scientists implanted an electrode near the boundary between the speech-related premotor and primary motor cortex (specifically, the left ventral premotor cortex). Neurites began growing into the electrode and, in three or four months, the neurites produced signaling patterns on the electrode wires that have been maintained indefinitely. Three years after implantation, the researchers began testing the brain-machine interface for real-time synthetic speech production.”
Read more at PhysOrg