47% of people have a nightmare at least once a month.
186
A hippo sleeping underwater automatically rises to the surface every ~4 minutes and breathes without waking.
23
The record for the longest scientifically documented period without sleep is 264.4 hours (eleven days).
15
One reason that kittens sleep so much is because a growth hormone is released only during sleep.
212
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 average person falls asleep in seven minutes.
115
44% of kids watch television before they go to sleep.
106