40 Facts about sleep from the National Sleep Research Project
40 Facts about sleep you probably didn’t know; some examples are ………..
– To drop off we must cool off; body temperature and the brain’s sleep-wake cycle are closely linked. That’s why hot summer nights can cause a restless sleep.
– Anything less than five minutes to fall asleep at night means you’re sleep deprived. The ideal is between 10 and 15 minutes, meaning you’re still tired enough to sleep deeply, but not so exhausted you feel sleepy by day.
-Elephants sleep standing up during non-REM sleep, but lie down for REM sleep.
– Ducks at risk of attack by predators are able to balance the need for sleep and survival, keeping one half of the brain awake while the other slips into sleep mode.
read more at:
http://www.abc.net.au/science/sleep/facts.htm