Sleep

A new video shows the rhythmic sloshing of cerebrospinal fluid in the human brain during sleep.

Although the exact cause of these experiences remains a mystery, the authors say the phenomenon may be tied to certain sleep abnormalities.

Even if humans have trouble telling time in the "land of the midnight sun," many animals can adjust their schedules to the summer solstice.

If you're not a morning person or a night person, but more like a midday person, don't feel left out.

Sleep learning, the way people commonly think of it, is almost certainly impossible. But researchers are discovering types of learning that occur during sleep, with exciting applications.

Scientists have yet to find a truly sleepless creature. But is sleep really necessary for survival?

A new study may have uncovered why a poor night's sleep is bad for your heart and blood vessels.

There's a new way of looking at insomnia.

This bad habit could raise your risk of serious eye infections and even lead to vision loss.

How did people wake up before the invention of modern alarm clocks?

A new, limited-time-only burger at Burger King has a peculiar selling point: It's supposed to give you nightmares.

Without these genes, there's no REM sleep.

Skimping on just one night's sleep may lead to changes that could promote weight gain and muscle loss.

Doctors have a very good reason for this recommendation.

Why the "it's just one night — it'll be fine" thinking might not work for contact lenses.

Sleep deprivation could contribute to loneliness, and the feeling is "contagious," researchers say.

Here's what you should know about sleeping with a fan on at night.

In waking life, such a case of quickly forgetting recent experiences would surely land you in a doctor's office. With dreams, however, forgetting is normal. Why?