“The Lost Hour”: Impact On Learning and School Performance

by Ms. S on September 29, 2010

—-

Shifting Weekend Sleep Leads To Lower IQ Points

“Dr. Monique LeBourgeois, also at Brown, studies how sleep affects pre-kindergartners. Virtually all young children are allowed to stay up later on weekends. They don’t get less sleep, and they’re not sleep deprived — they merely shift their sleep to later at night on Fridays and Saturdays. Yet she’s discovered that the sleep shift factor alone is correlated with performance on standardized IQ test. Every hour of weekend shift costs a child seven points on the test. Dr. Paul Suratt at the University of Virginia studied the impact of sleep problems on vocabulary test scores taken by elementary school students. He also found a seven-point reduction in scores. Seven points, Suratt notes, is significant: “Sleep disorders can impair children’s IQ as much as lead exposure.”

– Nurture Shock (2009) by Po Bronson and Ashley Merryman; page 33

A Slightly Sleepy Sixth-Grader Will Perform In Class Like A Mere Fourth-Grader

“Dr. Avi Sadeh at Tel Aviv University is one of the dozen or so big-wigs in the field, frequently collaborating on papers with the sleep scholars at Brown University…” He conducted a study on fourth-graders and sixth-graders. The children were studied in two groups: (1) the first group got 30 minutes more of true sleep per night; and, (2) the second group got 31 minutes less of true sleep.

“The performance gap caused by an hour’s difference in sleep was bigger than the gap between a normal fourth-grader and a normal 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 explained.”

– Nurture Shock (2009) by Po Bronson and Ashley Merryman; page 32

Every Fifteen Minutes Counts

“Teens who received A’s averaged about fifteen more minutes sleep than the B students, who in turn averaged fifteen more minutes than the C’s, and so on… Certainly, these are averages, but the consistency of the two studies stands out. Every fifteen minutes counts.”

– Nurture Shock (2009) by Po Bronson and Ashley Merryman; page 33

Tired Children Can’t Remember What They Just Learn ed

Tired children can’t remember what they just learned, for instance, because neurons lose their plasticity, becoming incapable of forming the new synaptic connections necessary to encode a memory.

– Nurture Shock (2009) by Po Bronson and Ashley Merryman; page 34

A Tired Brain Has A Harder Time Thinking Creatively

A different mechanism causes children to be inattentive in class. Sleep loss debilitates the body’s ability to extract glucose from the bloodstream. Without this stream of basic energy, one part of the brain suffers more than the rest — the prefrontal cortex, which is responsible for what’s called “Executive Function.” Among these executive functions are the orchestration of thoughts to fulfill a goal, prediction of outcomes, and perceiving consequences of actions. So tired people have difficulty with impulse control, and their abstract goals like studying take a back seat to more entertaining diversions. A tired brain perseverates — it gets stuck on a wrong answer and can’t come up with a more creative solution, repeatedly returning to the same answer it already knows is erroneous.

– Nurture Shock (2009) by Po Bronson and Ashley Merryman; page 34

The More You Learn During The Day, The More Sleep You Need

Both those mechanisms weaken a child’s capacity to learn during the day. But the most exciting science concerns what the brain is up to, when a child is asleep at night. UC Berkeley’s Dr. Matthew Walker explains that during sleep, the brain shifts what it learned that day to more efficient storage regions of the brain. Each stage of sleep plays its own unique role in capturing memories. For example, studying a foreign language requires learning vocabulary, auditory memory of new sounds, and motor skills to correctly enunciate the new word. The vocabulary is synthesized by the hippocampus early in the night during “slow-wave sleep,” a deep slumber without dreams. The motor skills of enunciation are processed during stage 2 non-REM sleep, and the auditory memories are encoded across all stages. Memories that are emotionally laden get processed during REM sleep. The more you learned during the day, the more you need to sleep that night.

To reconsolidate these memories, certain genes appear to upregulate during sleep — they literally turn on, or get activated. One of these genes is essential for synaptic plasticity, the strengthening of neural connections. The brain does synthesize some memories during the day, but they’re enhanced and concretized during the night — new inferences and associations are drawn, leading to insights the next day.

– Nurture Shock (2009) by Po Bronson and Ashley Merryman; page 35

A Good Night’s Sleep Is Important For Long-Term Learning

Kids’ sleep is qualitatively different than grownups’ sleep because children spend more than 40% of their asleep time in the slow-wave stage (which is ten times the proportion that older adults spend). This is why a good night’s sleep is so important for long-term learning of vocabulary words, times tables, historical dates, and all other factual minutiae.

– Nurture Shock (2009) by Po Bronson and Ashley Merryman; page 35

Sleep-Deprived People Fail To Recall Pleasant Memories, Yet Recall Gloomy Memories Just Fine

Perhaps most fascinating, the emotional context of a memory affects where it gets processed. Negative stimuli get processed by the amygdala; positive or neutral memories gets processed by the hippocampus. Sleep deprivation hits the hippocampus harder than the amygdala. The result is that sleep-deprived people fail to recall pleasant memories, yet recall gloomy memories just fine.

In one experiment by Walker, sleep-deprived college students tried to memorize a list of words. They could remember 81% of the words with a negative connotation, like “cancer.” But they could remember only 31% of the words with a positive or neutral connotation, like “sunshine” or “basket.”"

– Nurture Shock (2009) by Po Bronson and Ashley Merryman; page 35

Related Content:

“The Lost Hour”: Impact On Learning and School Performance

Search This Site:

Recalls by the U.S. Consumer Product Safety Commission

The S File ™ Tweets

All Posts