Someday, people who have lost their ability to speak may get their voice back. A new study demonstrates that electrical activity in the brain can be decoded and used to synthesize speech.

The study, published on Wednesday in Nature, reported data from five patients whose brains were already being monitored for epileptic seizures, with stamp-size arrays of electrodes placed directly on the surfaces of their brains.

As the participants read off hundreds of sentences—some from classic children's stories such as Sleeping Beauty and Alice in Wonderland—the electrodes monitored slight fluctuations in the brain's voltage, which computer models learned to correlate with their speech. This translation was accomplished through an intermediate step, which connected brain activity with a complex simulation