Have you ever woken up from a long night’s sleep and felt completely out of it? Like your brain was wrapped in cotton? That feeling isn’t your imagination. Oversleeping can mess with your internal ...

Now, a new neuroscientific study from MIT suggests a fascinating explanation. In short, when your attention vanishes after a sleepless night, your brain is literally flushing itself clean.

Sleep takes up nearly a third of our lives, yet much of what happens during those quiet hours remains unseen. Once thought to be a passive state, science now shows that sleep is an active process ...