Article stole from Chen. Lots of highlights because I need motivation to move my laptop out of my room (and there, hopefully, sleep more).
Highlights:
According to surveys by the National Sleep Foundation, 90 percent of American parents think their child is getting enough sleep. The kids themselves say otherwise. In those same surveys, 60 percent of high schoolers report extreme daytime sleepiness. In another study, a quarter admit their grades have dropped because of it. Over 25 percent fall asleep in class at least once a week.
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 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.
Dr. Kyla Wahlstrom of the University of Minnesota surveyed more than 7,000 high schoolers in Minnesota about their sleep habits and grades. 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.
Tired children can’t remember what they just learned, for instance, because neurons lose their plasticity, becoming incapable of forming the synaptic connections necessary to encode a memory.
The best known of these is in Edina, Minnesota, an affluent suburb of Minneapolis, where the high school start time was changed from 7:25 a.m. to 8:30. The results were startling. In the year preceding the time change, math and verbal SAT scores for the top 10 percent of Edina’s students averaged 1288. A year later, the top 10 percent averaged 1500, an increase that couldn’t be attributed to any other variable.
After the time change, teenage car accidents in Lexington were down 16 percent. The rest of the state showed a 9 percent rise.
Dr. Matthew Walker of UC Berkeley explains that during sleep, the brain shifts what it learned that day to more efficient storage regions of the brain. ... The more you learned during the day, the more you need to sleep that night.
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 get 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.
Dr. Eve Van Cauter at the University of Chicago discovered a “neuroendocrine cascade” that links sleep to obesity.
Sleep loss increases the hormone ghrelin, which signals hunger, and decreases its metabolic opposite, leptin, which suppresses appetite. Sleep loss also elevates the stress hormone cortisol. Cortisol is lipogenic, meaning it stimulates your body to make fat. Human growth hormone is also disrupted. Normally secreted as a big pulse at the beginning of sleep, growth hormone is essential for the breakdown of fat.
Vandewater analyzed the best large data set available, the Panel Study of Income Dynamics, which has extensively surveyed 8,000 families since 1968. She found that obese kids watch no more television than kids who aren’t obese. All the thin kids watch massive amounts of television, too. There was no statistical correlation between obesity and media use, period. “It’s just not the smoking gun we assumed it to be.”
Vandewater examined the children’s time diaries, and she realized why the earlier research had got it wrong. “Children trade functionally equivalent things. If the television’s off, they don’t go play soccer,” she says. “They do some other sedentary behavior.”
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.
The University of Pennsylvania’s David Dinges did an experiment shortening adults’ sleep to six hours a night. After two weeks, they reported they were doing okay. Yet on a battery of tests, they proved to be just as impaired as someone who has stayed awake for 24 hours straight.
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