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Can you be awake and asleep at the same time? - Masako Tamaki


16,169 Questions Answered

TEDEd Animation

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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? Masako Tamaki explores how animals' brains remain vigilant even at their most vulnerable.

Additional Resources for you to Explore

The state of sleep is measured objectively by a test known as polysomnography or PSG in humans. PSG consists of measurements of brain waves, eye movements and muscle tones. Brain waves are known as electroencephalography or EEG. EEGs are recorded from electrodes attached to the scalp. Eye movements are measured by electrodes attached on the face, two to three around eyes, also known as electrooculogram or EOG. Muscle tones are measured from two to three electrodes on the chin, known as electromyogram or EMG. By combining information from these electrodes, we can classify recordings into “sleep stages’.

Sleep can happen abruptly during the day when we are supposed to be fully awake and alert. This abrupt sleep is called microsleep or sleep attack. Microsleep may last from a couple of seconds up to about 30 seconds, shown here. Microsleep can occur without the person’s awareness of being asleep. Microsleep may occur with sleep deprivation and will usually entail “lapses” in performances. Lapses occur even when quicker responses are required, so they have been associated with life-threatening situations, like, sleeping while driving and possibly with other serious accidents. So sleep is very important to keep alert during the day!

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Meet The Creators

  • Educator Masako Tamaki
  • Director Biljana Labović
  • Narrator Jack Cutmore-Scott
  • Storyboard Artist Biljana Labović
  • Animator Iva Ćirić
  • Art Director Manja Ćirić
  • Sound Designer Weston Fonger
  • Composer Jarrett Farkas
  • Special Thanks Bill Plympton, Corey Allen Jackson
  • Director of Production Gerta Xhelo
  • Editorial Director Alex Rosenthal
  • Producer Bethany Cutmore-Scott
  • Associate Editorial Producer Cella Wright
  • Production Coordinator Abdallah Ewis
  • Script Editor Alex Gendler
  • Fact-Checker Jennifer Nam

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