The team wanted to know whether they could decode brain signals that are far more subtle than those produced by attempted speech. In imagined or inner speech, the individual merely thinks about a word or sentence — perhaps by imagining what it would sound like. JON HAMILTON, BYLINE: Brain computer interfaces, or BCIs, are experimental devices that can restore a paralyzed person’s ability to speak. HAMILTON: Farahany says surgically implanted BCIs will be regulated by the Food and Drug Administration, which could require privacy protections. HAMILTON: Farahany says she’s encouraged, though, that researchers are already looking for ways to help people protect their mental privacy.