When 25-year-old Pearl Kasirye heads to bed after a stressful day at work, she opens up the Calm sleep and meditation app and turns on a Sleep Story to help her nod off. Her favorite bedtime listening ...

The sleeping brain is more active if it hears unfamiliar voices rather than familiar ones. The finding suggests that we can process information about our environments even in the depths of sleep.

Jakke Tamminen receives funding from the Economic and Social Research Council and The Waterloo Foundation. Have you ever watched a duck sleep and wondered how it keeps one eye open? Ducks, like many ...