SciShow: Sleep: Why We Need It and What Happens Without It

  • Inactivity at night is an evolutionary adaptation that boosts an animals survival rate by keeping it out of danger when it would be most vulnerable 

    • keep still to attract less attention 

    • Sleep conserves energy 

      • Humans use about 10% less energy when sleeping than when awake 

  • When we sleep (body stuff): 

    • Grow muscle tissues

    • Cells synthesize proteins 

    • Tissues repair themselves 

    • Growth hormones are released...

TED: Why do we sleep? | Russell Foster

TED: The brain benefits of deep sleep | Dan Gartenberg

  • Benefits of good sleep include increased:

    • concentration

    • attention

    • decision-making

    • creativity

    • social skills

    • health

  • Benefits of good sleep include decreased:

    • mood changes

    • tendency to drink and take drugs

    • levels of anger,

    • impulsivity

    • stress...


  • Playing sounds that mirror brainwaves during the deep sleep stage might lead to deeper sleep

  • Potential benefits of this new tech for our health, memory and ability to learn.

Matthew Walker: The Effects of Alcohol & Marijuana on Sleep 


  • Alcohol and marijuana prevent the brain from going into REM-sleep (dream sleep) 

  • The brain keeps track of the dream sleep you lose, so that when the drugs are out of your system it actually goes into REM sleep more to make up from what it lost.