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sleep
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Hear how scientists are studying the sleep-related brain activity of animals and migratory birds
Electroencephalogram
Why does jet lag happen?
Do we really swallow spiders in our sleep?
How biological clocks influence daily behavior
how poor sleep affects pain
Why sleep is so important
Why smartphones can disrupt sleep
adult polar bear and cub
For Students
adult polar bear and cub
sleep summary
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Biology Bonanza
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sleep: Related Content

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News •

Sleep helps brain enter repair mode to clean up free radicals: Chinese study • May 26, 2025, 1:58 AM ET (South China Morning Post)
Max Richter's music put dozens of soldiers to sleep • May 16, 2025, 11:49 PM ET (CBC)

Photos and Videos

Electroencephalogram
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?
Do we really swallow spiders in our sleep?
How biological clocks influence daily behavior
how poor sleep affects pain
See All Videos and Images →

Related Topics and References

Topics
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Key People

Édouard Claparède
Swiss educator and psychologist

Related Quizzes and Features

Quiz
greylag. Flock of Greylag geese during their winter migration at Bosque del Apache National Refugee, New Mexico. greylag goose (Anser anser)
Biology Bonanza
List
Hand washing. Healthcare worker washing hands in hospital sink under running water. contagious diseases wash hands, handwashing hygiene, virus, human health
17 Questions About Health and Wellness Answered
Demystified
Persian cat is sleeping
Why Do Cats Sleep So Much?
Irish Cobs in autumn pasture, horses
Why Do Horses Sleep Standing Up?