The harder you concentrate on falling asleep, the less likely you are to fall asleep.
34
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
Honeybees never sleep.
276
The human brain is more active during sleep than during the day.
28
One reason that kittens sleep so much is because a growth hormone is released only during sleep.
212
There's a love mattress that is specifically designed for couples who sleep on each other's arms.
12
The record for the longest scientifically documented period without sleep is 264.4 hours (eleven days).
15