Fact or fiction: You can make up for lost sleep.
Get less than your usual amount of sleep and you can quickly incur what's called a "sleep debt," which can cause you to feel drowsy during the day. So, say you usually need a solid 8 hours per night, but for a week you have to stay up an extra 2 hours to study. Sure, you'll turn in your essay on time, but you'll probably feel sleepier than normally, since you’ve created a "sleep debt" of 14 hours. Eventually, your body requires you to pay off some of that debt. Well, you can "deposit" those lost hours later and reduce your sleep debt by taking extra-long slumber sessions, which may actually shake off some of that sluggishness.
Fact or fiction: You need less sleep as you age.
Though your needs decrease a bit after your childhood and teens, once you're an adult your needs will remain about the same from then on. The perception that older folks sleep less is a bit off. Actually, it's their sleep patterns that shift, not the number of hours spent snoozing. As people get older, they're more likely to fall asleep earlier in the evening and rise earlier in the morning, with more frequent daytime naps. Sleep may also become more "fragile" with age. That is, it becomes difficult to fall asleep and stay asleep, and there's a decline in the amount of time spent in deeper REM sleep.
Fact or fiction: Counting sheep can help you sleep.
A bit of both!
The idea of imagining trotting sheep leaping over a fence, one after another, helps to lull some people to sleep. The custom supposedly came into practice in the eighteenth century, but modern science - or our shrinking attention spans - seems to have placed doubts on this technique. In a study at Oxford University, a group of 50 insomniacs were told to try to fall asleep while thinking about counting sheep, a relaxing scene, or whatever they wanted. Those who thought of a relaxing scene fell asleep 20 minutes faster than those who envisioned of sheep or other thoughts. Seems leaping sheep just can't hold some folks' interest long enough to put them to sleep. Hmm, what if your ideal relaxing scene involves sheep?
Fact or fiction: Feeling drowsy by mid-afternoon is a sure sign that you need more sleep.
Daytime drowsiness can be one sign of sleep deprivation, but it's totally natural to feel a lull in your energy levels in the afternoon. There's a scientific reason for a siesta! Our bodies run on a biological clock throughout the day, and there are dips and peaks in our asleep-awake cycle. Adults are known to experience the strongest, most persuasive feelings of sleepiness at two times in the day: around 2 to 4 am and then again at 1 to 3 pm (with some variation depending on whether you're a "morning person" or "evening person"). This sleepiness varies in intensity, however, depending on whether we've had enough sleep. If you feel intense drowsiness during early afternoon, that may be a sign that you are sleep deprived. (If you feel it between 2 and 4 am, are you surprised? Go to bed!)