Demystifying Medicine Video

Sleep chronotypes are an idea coined by sleep researcher and author Dr. Michael Breus and widely explored in his book, The Power of When. Learn how your sleep animal (wolf, lion, bear or dolphin) can affect your daily life.

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  • Breus, M., & Oz, M. (2019). The power of when: Discover your chronotype--and the best time to eat lunch, ask for a raise, have sex, write a novel, take your meds, and more. New York: Little, Brown Spark.
  • Hirshkowitz, M., Whiton, K., Albert, S. M., Alessi, C., Bruni, O., Doncarlos, L., … Hillard, P. J. A. (2015). National Sleep Foundation’s sleep time duration recommendations: methodology and results summary. Sleep Health, 1(1), 40–43. doi: 10.1016/j.sleh.2014.12.010
  • Putilov, A. A., Donskaya, O. G., & Verevkin, E. G. (2015). How many diurnal types are there? A search for two further “bird species.” Personality and Individual Differences, 72, 12–17. doi: 10.1016/j.paid.2014.08.003
  • Sleep and Disease Risk. (n.d.).HealthySleep, Division of Sleep Medicine at
    Harvard Medical School.
  • Taillard, J., Philip, P., Coste, O., Sagaspe, P., & Bioulac, B. (2003). The circadian and homeostatic modulation of sleep pressure during wakefulness differs between morning and evening chronotypes. Journal of Sleep Research, 12(4), 275–282. doi: 10.1046/j.0962-1105.2003.00369.x
  • What's Your Sleep Chronotype - Decode Your Circadian Rhythm. (2019, August 21). BulletProof

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