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Students, Sleep, and Learning

download_pdf_smThe results of several different sleep studies have warned all of us – educators and parents – about the vital and serious consequences of too little sleep in children and teenagers. Examples of such studies are summarized in two articles that were published in New York magazine October 8, 2007. The articles, titled “Snooze or Lose” by Po Bronson and “How to Get Kids to Sleep More” by Ashley Merryman, can still be accessed at http://nymag.com/and are still relevant today. The articles were originally brought to CLI’s attention at a Curriculum Council meeting in a Kansas school district. Since that time numerous Councils in CLI districts have discussed this topic and made plans for communicating the information to parents. The following statements are taken directly from those articles with only minor changes made for emphasis.

Ninety percent of American parents think their child is getting enough sleep. The kids themselves say otherwise. Sixty percent of high schoolers report extreme daytime sleepiness. In another study, twenty-five percent admit their grades have dropped because of it. More than twenty-five percent fall asleep in class at least once a week.

Half of all adolescents get less than seven hours of sleep on weeknights. By the time they are seniors in high school they average only slightly more than 6.5 hours of sleep per night. Only five percent of high-school seniors average eight hours. Sure, we remember being tired when we went to school, but not like today’s kids.

It has been documented in a handful of major studies that children, from elementary school through high school, get about an hour less sleep each night than they did 30 years ago. While parents obsess over babies’ sleep, this concern falls off the priority list after preschool. Even kindergartners get 30 minutes less a night than they used to.

Until now, we could overlook the lost hour because we never really knew its true cost to children.

Using newly developed technological and statistical tools, sleep scientists have recently been able to isolate and measure the impact of this single lost hour. Because children’s brains are a work-in-progress until the age of 21, and because much of that work is done while a child is asleep, this lost hour appears to have an exponential impact on children that it simply doesn’t have on adults.

The surprise is how much sleep affects academic performance and emotional stability, as well as phenomena that we assumed to be entirely unrelated, such as the international obesity epidemic and the rise of Attention Deficit Hyperactivity Disorder.

The performance gap caused by an hour’s difference in sleep was bigger than the normal gap between a fourth-grader and a sixth-grader, which is another way of saying that a slightly sleepy sixth-grader will perform in class like a mere fourth-grader. “A loss of one hour of sleep is equivalent to [the loss of] two years of cognitive maturation and development,” explained one of the researchers.

“Sleep disorders can impair children’s I.Q.’s as much as lead exposure.”

Teens who received A’s averaged about fifteen more minutes sleep than the B students, who in turn averaged eleven more minutes than the C’s, and the C’s had ten more minutes than the D’s.

During sleep, the brain shifts what it learned that day to more efficient storage regions of the brain. Each stage of sleep plays a unique role in capturing memories. Memories that are emotionally laden get processed during R.E.M. sleep. The more you learned during the day, the more you need to sleep that night.

Sleep-deprived people fail to recall pleasant memories yet recall gloomy memories just fine.

“We have an incendiary situation today where the intensity of learning that kids are going through is so much greater, yet the amount of sleep they get to process that learning is so much less. If these linear trends continue, the rubber band will soon snap.”

Sleep is a biological imperative for every species on Earth. But humans alone try to resist its pull. Instead, we see sleep not as a physical need but a statement of character. It’s considered a sign of weakness to admit fatigue, and it’s a sign of strength to refuse to succumb to slumber. Sleep is for wusses.

Here’s the stuff they’d love to tell you, if they weren’t afraid of overwhelming you with science:

  • Ever wonder why most people sleep better when their bedrooms are cool? It’s because the circadian rhythm system that helps regulate sleep cycles is not just light sensitive, it’s temperature sensitive. Anything above a neutral air temperature both slows the body’s initiation of sleep and changes sleep patterns — a hotter room means an increase in non-REM sleep.
  • Seventy-seven percent of children use television as part of their pre-bedtime routine. Sitting still and vegging out for half an hour should, theoretically, help children unwind, as long as they’re not watching a show that excites them too much. However, the brightness of the screen undermines the theory. The light from a television or computer can delay both the necessary drop in core body temperature and melatonin production — thus delaying sleep onset — by two hours.
  • In one study of 170 children, those in white-collar families tended to be in bed later and get up earlier than those in working-class families. Yet they actually got more real sleep. How is that possible? It’s because their bedtimes and wake-times were more consistent; they stuck to their routines. This made their sleep more efficient — they rolled around in bed far less.
  • Inconsistent bedtimes are, for all practical purposes, homemade jet lag — the desynchronization of the two systems that regulate sleep, the circadian rhythm and the homeostatic pressure system. Staying up three hours later on weekends is equivalent to flying across three time zones every weekend.
  • A motivated student can sacrifice sleep to maintain high GPAs, but she may pay for that success with higher levels of depression and stress. Teen boys who have a high number of extracurricular activities are significantly more likely to be involved in a fall-asleep car crash. And those with part-time jobs both sleep less and have lower grades.
  • Naps are not quite the salve we imagine. They appease the homeostatic pressure system, but not the circadian. You wake up feeling better — a two-hour nap is equivalent to 150 mg of caffeine — but naps do nothing to repair diminished cognitive functioning. The intellect is just as dulled after the nap as before.
  • Sixteen percent of kids snore a few times a week. As recently as 2002, the American Academy of Pediatrics opined that children’s snoring was a benign condition not warranting treatment. Just five years later, researchers now caution that kids’ snoring is not like adult snoring at all — even a little snoring is a major cause for concern, because their developing brains can be deprived of oxygen.
  • Common sleep disorders such as nightmares, restless leg syndrome, and frequent night waking can have a startlingly negative impact on children’s development — from using drugs at age fourteen to having clinical-level anxiety as adults. Research by University of Michigan’s Dr. Ronald Chervin indicates as many as twenty-five percent of kids diagnosed with ADHD have an underlying sleep disorder causing their symptoms. If treated for their sleep disorder, the ADHD would magically disappear. Despite the risks posed by sleep disturbance, the number of children treated for them is “vanishingly small.” Parents should consult a qualified sleep specialist — few pediatricians have expertise with sleep problems. Waiting to see if a child grows out of a sleep problem isn’t the answer.