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Getting Enough Sleep?

By Emily Sohn

One of the greatest things about growing older is that you get to stay up later. And it’s not just your parents who make that decision. Your body gives you permission to enjoy the darker hours too. Recent research has shown that brain changes during teen years make it easier for kids to stay up late.

But just because you can stay up late, it doesn’t mean you should, scientists say. Young people who don’t get enough sleep are often late for school, or they miss it completely, says a recent study by the National Sleep Foundation (NSF). Sleepy kids also tend to be bad-tempered and unhappy. And their grades suffer. Our sleep-wake schedules may seem to be ruled by the need to get to school or work on time, but they’re really under the control of our body’s internal clock. Every mammal has a “master clock” in its brain that tells its body what time it is and when it needs to sleep. Scientists recently discovered cells in the brain that collect information about light directly from the eyes. When light comes in, our internal clock thinks that it’s daytime. Then, as darkness arrives, the body secretes a chemical called melatonin, which tells the clock that it’s nighttime. As we approach our teen years, melatonin secretion comes at a later time. That’s why children who usually go to bed at 8:30 or 9 p.m. all of a sudden start having trouble falling asleep.