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About TED-Ed Originals

TED-Ed Original lessons feature the words and ideas of educators brought to life by professional animators. Are you an educator or animator interested in creating a TED-Ed original? Nominate yourself here »

Meet The Creators

  • Educator Nathan S. Jacobs
  • Director Hector Herrera
  • Producer Pazit Cahlon
  • Script Editor Alex Gendler
  • Narrator Addison Anderson


Additional Resources for you to Explore
Understanding the function of spontaneous, internally generated brain activity is still a very new and unexplored field of neuroscience.

Are you interested in how internally generated biological clocks control our sleep patterns and other aspects of our lives? Watch the TED Talk Our natural sleep cycle. Then watch Why do we sleep? This talk features a circadian neurologist, Russell Foster. What do you think a circadian neurologist does? What are circadian rhythms and why are they important? Interested in learning more about the teenage brain then visit Frontline’s Inside the Teenage Brain. Why might it be important to your health to be aware of how the brain functions?

Interested in REM and its importance to memory consolidation? What does it have to do with dreams? Visit this site and find out. Interested in sleep research, and how it started? Read Elizabeth Kolbert’s article, Up All Night: The science of sleeplessness. What effect might staying up all night have on the functioning of the brain? Why do we sleep?, an article from Nature Neuroscience provides insight into why we need to sleep seven to eight hours per day. Then Watch One Family, Different Clocks; a Tale of the brain, genes and sleep cycles. Learn how genetics can alter the body’s internal clock at

Spontaneous activity in the retina occurs every time you sleep. Here is an interactive demo showing how spontaneous activity and changes in spontaneous activity are essential to how retinal ganglion cells encode visual information. (NOTE: click “step through” button on the left, then go to slide 8)