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Waking Up and Feeling Sleepy

There are five stages of sleep. (Ana C, Flickr)

Are you familiar with sleep inertia?

It's that groggy, slow feeling when you first wake up. According to a study, that blurry feeling you have when you first wake up is kind of like being drunk.

Complex Thinking



The feeling sometimes only lasts a few minutes, but its effects can linger for a few hours. The study tested the problem-solving abilities of people who had just awakened from eight hours of sleep.

It turns out that the subjects performed most poorly during the first three minutes after waking up. There's some evidence suggesting that the areas of the brain in charge of problem solving and complex thought take longer to wake up than other parts.

This might sound like a minor inconvenience or something not worth studying, but if you're a doctor or firefighter or anyone who might have to wake up suddenly and snap into action, sleep inertia is a bigger deal.

Sources And Further Reading:



  • Hilditch, Cassie J. Dorrian, Jillian. Banks, Siobhan. Time to wake up: reactive countermeasures to sleep inertia.I nd Health. 2016 Nov; 54(6): 528–541.

    Published online 2016 May 18. doi: 10.2486/indhealth.2015-0236

  • "Napping." National Sleep Foundation: Sleep Topics: Napping. Accessed August 20, 2018.
  • "What Is Sleep Inertia, and How Can I Beat It?." Huffington Post: The Blog. December 16, 2017. Accessed August 20, 2018.


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