The harder you concentrate on falling asleep, the less likely you are to fall asleep.
34
Bats sleep 18-20 hours per day.
5
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
The higher someone’s I.Q. the more likely they are to be sleep deprived.
29
A hippo sleeping underwater automatically rises to the surface every ~4 minutes and breathes without waking.
23
Quick naps not only improve your alertness, but they also help in decision making, creativity and sensory perception.
149