A hippo sleeping underwater automatically rises to the surface every ~4 minutes and breathes without waking.
23
The strangers in your dreams are actually people that you've seen in real life.
50
You forget 90% of your dreams.
256
The human brain is more active during sleep than during the day.
28
Sleeping on your stomach can induce weirder, scarier, and sexier dreams.
22
If you hold farts in during the day, they'll just come out when you sleep.
16
The higher someone’s I.Q. the more likely they are to be sleep deprived.
29