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Want to make your children smarter by two years? Put them to bed earlier


I saw this TV programme last week, where ‘Super Nanny’ Jo Frost had a group of children change the amount of sleep they had to see if it affected their performance. I was astonished at how much the amount of sleep a child impacted on their ability to perform tasks like verbal fluency. Jo Frost: Extreme Parental Guidance 

Half of all parents don’t know what time their kids should be going to bed. They don’t know how much sleep their kids need.

Does it matter? Does lack of sleep in children have any impact on them other than feeling a bit tired?

Jo Frost put a group of 8 – 11 year olds through a series of tests to see if how much sleep they got affected their mental abilities.

Dr Cathy Hill, an expert in pediatric sleep disorders, who is conducting the tests, states: “Sleep is important for just about everything for children – their physical growth, their learning, their behaviour, their development…There is evidence that over the last 20 years children are getting less sleep than they used to”

The children taking part in the tests have an average bedtime of 9.00pm, giving them the recommended 10 hours per night.

The first test was allowing the children to stay up for as long as they wanted for 6 nights in a row, but no later than 11.00pm, however they had to be up at their usual time and to school on time. All the children opted to stay up for as long as they were allowed, often playing stimulating games, like play-station or watching DVDs that kept them awake.

In the classroom – it was obvious that they struggled, and were yawning through lessons. To see if there was any other impact the children were put through a series of psychological and cognitive tests at Middlesex University.

The first test was verbal fluency where children had to name as many fruit (or similar common thing) as they could in a minute. Dr Hill pointed to children’s body movements which appeared overactive, like constant leg swinging, and fidgetting, explaining that this is the body’s way of keeping the brain engaged. All children showed poor verbal fluency with some only managing to think of 10 or 11 fruit in a minute.

The next test was an eye tracker which measures how easily kids can be distracted while carrying out a simple task. An important ability for a child is to maintain focus on a task. 80% of the sleep deprived children struggled to complete the task.

Across the range of tests a week of late nights has shown the average mental age of the children decline from 10 to 7 years!

The second part of the sleep experiment is to find out what happens if kids get more sleep than they normally do. Dinner at 6.00pm, wind down time from 7.00. The new bedtime is set at 7.30, quiet reading until 8.00pm and then lights out.

This will give the children an hour extra than they had normally been having. It will also give them 11 hours sleep a night – an hour more than is currently recommended.

There is no point to sending kids to bed earlier if they have stimulating gadgets to keep their minds awake, so all distractions are to be taken out of the bedroom, all computers, games, cellphones, and TVs. The number of electronic gadgets taken from each child’s room was mind boggling – as one parent noted “It’s awful when you think about how much they’ve got that allows them to sit in room on their own and just occupy themselves – it’s terrible” What was also noticed by parents is that the children could actually go to sleep earlier when they had wind down time, without the usual stimulation like TV and electronic games.

After having 11 hours sleep a night for one week, the children were put through the same raft of tests.

The 10 yr old boy who managed only 10 fruits in a minute when tired, increased his verbal fluency dramatically and could think of 23 animals in a minute. By the end of the tests the children’s performance in almost unrecognisable. This time every child completed the eye-tracker test with improved speed and accuracy. Across the range of tests their mental age increased by two years to age 12, a huge increase on the week before that showed their mental age drop to that of a 7 year old.

Dr Hill states she was genuinely amazed by the results, “I think it is important to recognise that normally children normally don’t make changes in these tests from week to week, normally we’d expect these sorts of improvements to take place over months of a child’s development. Parents spend extra money giving children extra tuition, sending them off to classes, what this is suggesting is that if children were sent off to bed earlier, get a better night’s sleep, children could improve in their day to day function fairly significantly.”

TV on demand, available until 23rd December 2010 Jo Frost: Extreme Parental Guidance

More on the subject of sleep and performance in children.
From Tel Aviv University. Snooze or Lose (New York Times)

Here is an excerpt:

Dr. Avi Sadeh of Tel Aviv University is one of the authorities in the field. A couple of years ago, Sadeh sent 77 fourth-graders and sixth-graders home with randomly drawn instructions to either go to bed earlier or stay up later for three nights. Each child was given an actigraph (a wristwatchlike device that’s equivalent to a seismograph for sleep activity), which enabled Sadeh’s team to learn that the first group managed to get 30 minutes more sleep per night. The latter got 31 minutes less sleep…

After the third night’s sleep, a researcher went to the school in the morning to test the children’s neurobiological functioning. The test they used is highly predictive of both achievement-test scores and how teachers will rate a child’s ability to maintain attention in class.

The effect was indeed measurable—and sizable. 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,” Sadeh explains.

This is a much smaller sleep difference than the trial carried out by Jo Frost. As parents this my be the simplest thing we can do to increase the ability of our children.

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