The question of how children acquire language has long intrigued parents and scholars. MIT cognitive scientist Deb Roy recently found a novel way to study what he calls “word birth.” He wired his home with cameras and microphones, and recorded his infant son’s every utterance as he grew into toddlerhood. He then combined the 90,000 hours of video and 140,000 hours of audio into some astonishing montages. Dr. Roy shared his findings at a TED conference. More visuals and audio from the study in this article from Fast Company. This is part of a complete episode.