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 cat sleeps about 2/3 of the day.
203
Sleeping on your stomach can induce weirder, scarier, and sexier dreams.
22
Studies show that the colder the room you sleep in, the more likely you are to have a bad dream.
28
47% of people have a nightmare at least once a month.
186
You forget 90% of your dreams.
256
Quick naps not only improve your alertness, but they also help in decision making, creativity and sensory perception.
149