Previous work has described a neuroprosthesis to directly decode full words in real time during attempts to speak. Here the authors demonstrate that a patient with anarthria can control this neuroprosthesis to spell out intended messages in real time using attempts to silently speak.

Speech unfolds faster than the brain completes processing of speech sounds. Here, the authors show that brain activity moves systematically within neural populations of auditory cortex, allowing accurate representation of a speech sound’s identity and its position in the sound sequence.