The harder you concentrate on falling asleep, the less likely you are to fall asleep.
34
A hippo sleeping underwater automatically rises to the surface every ~4 minutes and breathes without waking.
23
Cows can sleep standing up, but they can only dream lying down.
745
44% of kids watch television before they go to sleep.
106
Some people have a "natural alarm clock" allowing them to wake up when they want. This is actually caused by a burst of the stress hormone adrenocorticotropin.
15
Blue light fends off drowsiness in the middle of the night, which could be useful to people who work at night.
240
47% of people have a nightmare at least once a month.
186