If you woke up feeling unusually refreshed this morning, that might be because you finally got enough sleep. The clocks went ...

Phones have replaced many things: computers, calculators, cameras and maps. But returning to an old-fashioned alarm clock instead of your phone might help you get up and go in the morning.

Participants lived in a controlled environment over seven 28-hour sleep/wake cycles where all external time cues—including clocks and natural light—were removed.