sleep: Quick Facts

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Last updated

Nov. 10, 2026

News •

Novel treatment clears dementia-linked proteins from the waking brain • Nov. 4, 2026, 12:31 PM ET (News-Medical)

Jumping spiders caught on camera sleeping and leg twitching like humans • Oct. 26, 2026, 11:49 PM ET (ABC News (Australia))

Study Connects Caffeine, Sleep And Mental Health In Children • Oct. 22, 2026, 10:04 AM ET (U.S. News & World Report)

New type of depression is related to sleep, scientists report • Oct. 20, 2026, 7:00 PM ET (Live Science)

"Mind-blowing" Alzheimer’s breakthrough: Two hours of sleep restored without clearing brain plaques • Oct. 19, 2026, 5:27 AM ET (Science Daily)

Photos and Videos

A diagram of EEG tracings displays brain wave patterns for wakefulness and three sleep stages, highlighting features like theta waves, sleep spindles, K-complexes, and slow waves.

adult polar bear and cub

Hear how scientists are studying the sleep-related brain activity of animals and migratory birds

Why does jet lag happen?

Image thumbnail shows a illustration of a shark resting its head on a pillow.

A man sleeps with his mouth open on a bed, while a large spider sits on the pillow near his hand.

How biological clocks influence daily behavior

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Topics

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Key People

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Édouard Claparède

Swiss educator and psychologist

greylag. Flock of Greylag geese during their winter migration at Bosque del Apache National Refugee, New Mexico. greylag goose (Anser anser)

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