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The Kid Should See This

Asymmetrical sleep: Can you be awake and asleep at the same time?

Many animals need sleep. But all of the threats and demands animals face don’t just go away when it’s time to doze. That’s why a range of birds, mammals, and even humans experience some degree of asymmetrical sleep, where parts of the brain are asleep and other areas are more active. So, how does it work?

Can you be awake and asleep at the same time? Ask a dolphin, who famously sleeps with one eye closed and one eye open while it sleeps. Dolphin sleep patterns, known as unihemispheric slow-wave sleep, allow them to rest one brain hemisphere at a time.

dolphins
This TED-Ed lesson by Masako Tamaki, directed by Biljana Labović, designed by Manja Ćirić, and animated by Iva Ćirić, describes explores the science of sleep, specifically a phenomenon known as asymmetrical sleep, “where parts of an animal’s brain are asleep while other areas remain active.”

This is true for humans, too, though to a more subtle degree. Dig Deeper with TED-Ed.com.

studying human sleep
Watch these related videos about sleep next:
The benefits of a good night’s sleep
• Why do we sleep and how do different animals sleep?
• How the Animal Kingdom Sleeps
• What’s the difference between hibernation and sleep?
• Naps, a collection film by The Mercadantes

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