47% of people have a nightmare at least once a month.
186
Quick naps not only improve your alertness, but they also help in decision making, creativity and sensory perception.
149
A hippo sleeping underwater automatically rises to the surface every ~4 minutes and breathes without waking.
23
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
The human brain is more active during sleep than during the day.
28