Only Professional Sleepers Can Score 7/10 On This Quiz

There are five stages of sleep. There are four stages of non-REM sleep and one stage of REM sleep. REM stands for "rapid eye movement" and is the stage typically associated with dreaming (your body also goes into paralysis so you don't act out your dreams).

The average duration of a sleep cycle is 1.5 hours or 90 minutes. You should aim to go through at least 5-6 sleep cycles a night.

You shouldn't drive at all when you're tired! Drowsy driving is just as bad as drunk driving and it only takes a four second lapse in attention to have a potentially fatal accident.

You cannot make up sleep. Sleep is not a debt that you can just pay back, especially if there are important things you wanted to remember the day before. Lack of sleep, the night after learning, causes catastrophic forgetting that never improves, even after several nights of "recovery sleep."

Alcohol only sedates you and sedation is NOT the same as sleep. In fact, drinking alcohol before bed disrupts your REM sleep, which is important for consolidating memories.

Sleep deprivation can cause obesity. Lack of sleep has effects on your levels of ghrelin and leptin -- hormones that regulate your appetite. When you don't get enough sleep, you have higher levels of ghrelin, which promotes hunger, and lower levels of leptin, which inhibits your appetite, leading you to eat more than you need to.

Sleeping helps us learn. Memories are first formed in the region of your brain called the hippocampus. Studies have shown that sleep deprivation before learning something new leads to poor recall, even if you sleep well after learning, suggesting that sleep helps clear the hippocampus of old memories to make room for new ones.

Melatonin only tells your body when it's time to get ready for bed -- it doesn't help you fall asleep nor stay asleep.

Multiple studies have shown that taking a nap right after learning new information results in better recall the next day. Even a nap as short as five minutes can be effective!

Studies have shown that partial sleep deprivation (i.e. sleeping 4 hours/night) can have effects equivalent to pulling one all-nighter. Another study in the group showed that even after several nights of recovery sleep, none of the sleep deprived groups returned to their cognitive functioning baseline.