He also authored one of the great books on the subject ... (energetic music) - So Matt, why do we sleep? - Well, 50 years ago, the crass and very unhelpful answer to that question was that ...

The discovery, made by a team primarily from the University of Tsukuba and published in the British scientific journal Nature on Dec. 8, provided some answers to an age-old question: Why do living ...

We sleep for a third of our lives and there are many restorative processes going on during sleep that are needed to stay healthy. Why do we usually sleep at night? What happens when we don't sleep?