Are your children walking zombies?

I have an important question — actually, several related questions — for all parents of school-age children: Do you know how much your children sleep? Do you know how much sleep they really need? And do you know what their biological clocks are telling them about when to go to sleep and when to wake up?

Although young children are likely to arouse their groggy parents every morning, with no respect for weekends, after puberty the tables turn. Often I hear a familiar lament from parents of adolescents: Every day it’s a struggle to get the kids up and out to school on time.

Many youngsters and most teenagers do not get enough sleep, and this can result in serious consequences, impairing school performance and even raising the risk of depression and other mood disorders.

To help you and your children better appreciate their sleep needs, I’d like to suggest a little test. For a week or two before school ends and again during summer vacation, keep a three-column sleep diary for your children. Or, if they are able and willing, ask them to do it themselves.

In one column, record lights-out time during the school week and on weekends or vacation days. In a second column, record sleep latency — that is, how long it takes them to fall asleep. And in the third column, record wake-up time, noting whether arousal occurs naturally or with an alarm (or dousing with cold water!).

While it’s true that sleep needs vary from one person to another, there are some very reasonable, science-based guidelines to help you determine whether children are getting the sleep they need to function at their best in school and at play and to get along well with friends and relations.

And if you are a parent of teenagers, you may come to a much better understanding of why they have so much trouble getting up on school mornings in time to wash, dress, eat breakfast and get to the bus or their first class on time.

In years past, TV got all the blame for curtailing the sleep of the younger set. Now, the modern devices that were meant to enhance communication and save us so much time have created nearly endless days. There is no longer a ‘sacred’ hour beyond which a child cannot contact someone, search for information or shop online. And for far too many youngsters, sleep takes a back burner to staying in touch, whether by cellphone, email, instant or text messages or Skype.

According to the National Sleep Foundation, newborns should sleep 12 to 18 hours out of every 24 (every new parent hopes), with a gradual reduction to 12 to 14 hours for toddlers ages 1 to 3; 11 to 13 hours for preschoolers 3 to 5; and (yes!) 10 to 11 hours for schoolchildren ages 5 to 10.

I suspect, though, that relatively few fourth and fifth graders get 10 hours of shut-eye a night. My grandsons, at 10, were lucky to sleep eight or nine hours, even on weekends. Researchers at Stanford University have reported that 9-and 10-year-olds need only about eight hours a night.

But things get really challenging at puberty and throughout adolescence. Not only do teenagers need more sleep than adults but the times at which they get sleepy and are able to awaken naturally and feel rested shift in a way that does not mesh with the start times at most schools.

The typical teenager, sleep studies have shown repeatedly, does not fall asleep readily before 11 pm or later. Yet many have to get up by 6 am or earlier to get to school for a class that starts at 7:30 or 8 am. More than a few doze off during that class, and often the next one as well. Even if awake, they’re in no condition to learn much of anything.
In one study, more than 90 per cent of teenagers reported sleeping less than nine hours a night, and 10 per cent said they slept less than six hours. As James B Maas, Cornell University, has observed, most teenagers are ‘walking zombies’ because they get far too little sleep.

Even in 1998, before smartphones and iPads could be blamed for teenagers’ sleep deprivation, a study of more than 3,000 adolescents by two sleep specialists, Amy R Wolfson, College of the Holy Cross, and Mary A Carskadon. Brown University, found that high school students who got poor grades slept an average of 25 minutes less and went to bed 40 minutes later than those who got A’s and B’s. In a laboratory study of 40 high school students, Mary and colleagues found that nearly half the students who began school at 7:20 am were ‘pathologically sleepy at 8:30 am. Calling such early start times ‘abusive,’ she said, “These kids may be up and at school at 8:30, but I’m convinced their brains are back on the pillow at home.”

“Students are not awake enough to attend to information they’re supposed to be learning, their knowledge acquisition is impaired and their ability to retrieve information is reduced,” she said. “What is learned during the day is consolidated during sleep.”
After five nights of too little sleep, many teenagers try to catch up on the weekends, sleeping until 11 am or noon, if not later. But, Mary said, this solution can backfire because it further distorts their biological clocks and can make it even harder for them to get up on time during the school week.

Other consequences of sleep deprivation in youngsters include “an erosion of happiness — an increased risk of depression and other mood disturbances” in those with an underlying vulnerability.

School districts that have switched to later start times for high school students have noted an improvement in grades, a decrease in dropouts and a reduction in traffic accidents. By shaving five minutes off the time between classes, one district avoided having to extend the school day, which might otherwise interfere with sports programmes and jobs.

If you’ve kept a sleep diary for your children, look for a discrepancy between their sleep needs on nonschool days and what they must do during the school year.

Mary, who described adolescence and sleep as ‘the perfect storm,’ offered these tips that could result in a better match between teenage sleep schedules and school demands:
* School districts should start the day later for adolescents.
* School-sponsored late-evening activities should be limited.
*The curriculum should include information about sleep and biological rhythms to encourage students to make informed choices about their sleep schedules.
* However, parents should identify and set ‘an appropriate bedtime.’
* To help establish an acceptable sleep-wake cycle, teenagers should avoid bright light and stimulating activities in the evening and get light exposure in the morning.
* Families should establish relaxing pre-sleep rituals, reminiscent of the bedtime stories of early childhood.