Sleep Improves Children’s Ability to Absorb Information and Learn

By Matthew D. Mingrone, M.D. of eOs Sleep

It has been common scientific knowledge for some time that when people sleep, our brains consolidate the information we subconsciously absorb during the day, and process it into explicit, conscious knowledge.

Both children and adults do this, but an interesting new study out of Germany shows that during sleep, children's brains convert subconsciously absorbed information—known as implicit learning—into active, useful knowledge even more effectively than adult brains do.
Implicit learning is typically considered subconscious learning; the acquisition of knowledge independent of conscious attempts to learn. For example, a child can say a sentence without understanding the rules of English grammar.

Explicit learning, on the other hand, is deliberate, conscious learning; the active and aware acquisition of skills and/or knowledge. Typically, explicit learning is accompanied by “meta-awareness,” a person can explain how they acquired the skill and/or knowledge.
When we sleep, implicit knowledge becomes explicit memory, making it easier for us to recall and use the information we have previously absorbed.

In a new study conducted by Dr. Ines Wilhelm of the University of Tübingen's Institute for Medical Psychology and Behavioral Neurobiology in Germany, and colleagues, the researchers studied 35 children between the ages of 8 and 11 years old, as well as 37 adults between 18 and 35.

For the test, the subjects were asked to press a sequence of buttons after they lit up. Half of the subjects did the test before sleep, the other half after sleep. They were then asked to recall the sequence of buttons/lights 10 to 12 hours later. Following a night of sleep or a day awake, the subjects’ memories were tested.

An article explaining the results of the study, entitled, “The sleeping child outplays the adult's capacity to convert implicit into explicit knowledge,” is published in the February 24, 2013 online edition of Nature Neuroscience.

The authors observed that after a night’s sleep, both age groups—8 to 11 and 18 to 35—remembered a larger sequence of buttons/lights than those who did not sleep. It also showed the children were better at it than the adults—almost all of the children could remember the sequence they had pressed perfectly, while adults experienced smaller gains.

Lead author Dr. Ines Wilhelm wrote, “In children, much more efficient explicit knowledge is generated during sleep from a previously learned implicit task. And the children’s extraordinary ability is linked with the large amount of deep sleep they get at night. The formation of explicit knowledge appears to be a very specific ability of childhood sleep, since children typically benefit as much or less than adults from sleep when it comes to other types of memory tasks.”

Children absorb massive amounts of information every day. They also generally sleep longer and deeper, and experience three times more slow-wave sleep and higher electrical activity in the brain during sleep than adults. This may help them “convert” the information they take in every day into knowledge they can recall and use. This is yet another important reason why parents should ensure their children are getting enough uninterrupted sleep every night.

A Good Night’s Sleep Can Be a Matter of Life and Death

Over the past three years, I have been writing the Wake Up! You’re Snoring blog with two main objectives: first, to educate you, the public, about sleep disorders, and second, to provide compelling reasons—preferably scientific evidence—why a person who may have a sleep disorder should get diagnosed and, if necessary, properly treated.

There is no shortage of scientific studies being released on a regular basis showing links between obstructive sleep apnea (OSA), insomnia, and other sleep disorders, and myriad negative health conditions, from daytime sleepiness to increased depression.

I wasn’t surprised to see a new study showing a link between insomnia, the loss of hope, and an increased risk of suicide. In a study led by Dr. W. Vaughn McCall, chair of the Medical College of Georgia at Georgia Regents University, researchers studied the mental state of 50 depressed patients between the ages of 20 and 80. More than half of the patients had attempted suicide, and most were taking an antidepressant.

It is established that insomnia and nightmares often go hand-in-hand, and are both known risk factors for suicide. The new study reaffirms that link, but researchers also wanted to find out what effect feelings of hopelessness about sleep had on suicide risk.

In the study, the researchers specifically focused on the relationship between insomnia and suicide risk by asking questions about dysfunctional beliefs about sleep, such as, “Do you think you will ever sleep again?” The scientists used psychometric testing to objectively measure the mental states and personalities of the 50 depressed patients.

Dr. McCall published the results of the study in the Journal of Clinical Sleep Medicine, the journal of the American Academy of Sleep Medicine. In the report, Dr. McCall stated, “It turns out insomnia can lead to a very specific type of hopelessness, and hopelessness by itself is a powerful predictor of suicide.” Dr. McCall also said, “The likelihood of being suicidal at least doubles when insomnia is a symptom.”

McCall and his colleagues have, in effect, discovered a new predictor for suicidal thinking. But why the link between lack of sleep and suicidal thoughts? Dr. McCall explained that, “It turns out insomnia can lead to a very specific type of hopelessness, and hopelessness by itself is a powerful predictor of suicide.” He continued, “If you talk with depressed people, they really feel like they have failed at so many things. It goes something like, ‘My marriage is a mess, I hate my job, I can’t communicate with my kids, I can’t even sleep.’ There is a sense of failure and hopelessness that now runs from top to bottom, and (insomnia) is one more thing. It was this dysfunctional thinking — all these negative thoughts about sleep — that was the mediating factor that explained why insomnia was linked to suicide,” said McCall.

The significance of this study, like many others, is that it not only educates people about the risks associated with insomnia and other sleep disorders, but it challenges the medical community to look at things a little differently when diagnosing and treating.

In this case, examine lack of sleep and insomnia when treating depression and suicidal thinking.  The finding also is a reminder to physicians that depressed patients who report increased sleep problems should be asked if they are having suicidal thoughts, McCall said.

If you’re having trouble sleeping, here are some tips to increase your chances of getting a good night’s sleep.

• Use the bedroom for sleep. With so many electronic distractions in our lives, it’s important to re-claim your bedroom for its intended purpose: rest and sleep. Move the TV and computer out of the bedroom, or at the very least, do not watch TV, work on the computer or check your blackberry close to bedtime.
• Stick to a bedtime routine. Try to go to sleep before 10:00 pm at night, and wake up around the same time every day, even on weekends. Try to keep to within 20 minutes of the same time each morning and night.
• Do activities that will get you ready for bed. Before bed, do activities that will promote sleepiness, such as a taking a warm bath, or reading a book or magazine.
• Maintain a cool temperature in your bedroom. A cool but comfortable temperature is ideal for sleep. Too warm and you will be fitful, too cold however can be uncomfortable and disturb your sleep.
• Exercise regularly but not after the late afternoon. Even though exercise helps regulate sleep, rigorous exercise causes endorphins in the body to circulate which can have a stimulant effect, and keep you awake longer at night.
• Stay away from caffeine at night. The effects of caffeine are different from person to person, and may last hours after your last cup of coffee, so make your last cup of coffee, regular tea or soda earlier in the day.
• Avoid alcohol and medicines that make you drowsy. Even if you think it is helping you fall asleep initially, alcohol and medicines that makes you drowsy may affect your sleep throughout the night.

Remember, people need an average of 7-8 hours of restful sleep to fully take advantage of its restorative power and avoid daytime symptoms of fatigue. If a regular, peaceful routine incorporating the tips above doesn’t help you start sleeping peacefully throughout the night, contact your doctor. You may have a more serious cause of sleeplessness such as snoring, sleep apnea or chronic insomnia. Getting treated could prevent heart disease, hypertension and stroke.