College freshman Edie Weiner arrived home for winter break on a Saturday night, fell into her childhood bed and didn't get up for 20 hours.

By the time the 18-year-old stumbled out from hibernation at 5 p.m. the next day, her parents were growing a bit anxious.

Weiner, like many of her classmates, was recovering from a sleepless, caffeine-fueled week of cramming for finals – a sort of celebrated ritual that has long played out on college campuses.

But while some parents may be annoyed about their teenagers' unusual sleep patterns when they return home for break – the word “lazy” might even be muttered on occasion – medical experts describe the students as sleep-deprived and say new research provides cause for concern.

A study published in the Dec. 18 issue of the Nature Neuroscience journal examined how memories are processed in the brain during sleep. During the nondreaming portion of sleep, the brain replays the day's events, helping people reflect on recent happenings and learn from them, says Matthew Wilson, a neuroscientist at the Massachusetts Institute of Technology's Picower Institute for Learning and Memory.

The bottom line: Information crammed into the brain during a sleepless night has less chance of sticking. When deprived of sleep, students may be able to regurgitate information they've memorized overnight, but they have decreased their ability to understand its meaning or to apply it to future experience.

“Sleep isn't just a passive event,” says Wilson, co-author of the study, which interpreted the memories of rats by inserting electrodes into their brains.

“The best way to take advantage of sleep is to have it interspersed between periods of wakefulness in a regular way,” he says.

Parents may feel better about cramming for exams because they see that when their exhausted students return home for break, they sleep excessively to catch up.

“They are trying to replenish themselves,” says Dr. Phyllis Zee, a neurology professor and director of Northwestern University's Center for Sleep and Circadian Biology. But both she and Wilson say sleep gained days later isn't as beneficial as systematic sleep.

“You can't make up for the lack of past sleep by just loading up on it,” says Wilson. Adding to the problem, Zee says, is that many students don't return to a healthy sleep pattern after recuperating from exam week.

Since emerging from her sleepathon, Weiner often awakens at 9 a.m. for breakfast, then naps from 1 p.m. to 4 p.m. before heading out the door to hang with friends until 2 a.m. or so.

“[My parents] don't think it's typical, but I do,” says Weiner.

Weiner concedes she spent too much time socializing at school and found herself sleeping through some of her classes. She isn't sure she will resume her equine studies classes next semester.

“She just went kind of crazy at school,” her mother, Gwen Weiner, says with a sigh. “Where the problem comes in is the maturity and making the right decisions.”

Researchers are still studying the long-term ramifications of sleep deprivation, but this much they know: It can lead to chronic fatigue, depressed moods, irritability, headaches and weight gain.

Studies also show there is a relationship between people who sleep less than six hours on average and the likelihood of developing metabolic disorders, such as diabetes, cardiovascular disorders and high blood pressure, Zee says.

While few studies have focused on college students, researchers know that teens often begin to sleep less during their high school years, when their circadian rhythms, or internal clocks, shift by several hours, she says.

The independent National Sleep Foundation released poll results last March showing that only 20 percent of adolescents get the recommended nine hours of sleep on school nights. The poll, which consisted of a random phone survey of 1,602 caregivers and their children in Grades 6 through 12, also reported that as the child ages, the amount of sleep declines. By 12th grade, the students slept an average of 6.9 hours nightly.

By college, some students learn their limits quickly.

Emily Avellone, 20, a junior at the University of Illinois at Chicago, says she signs up for classes only if they are scheduled at 11 a.m. or later.

“These days, there is no way I would be able to get up for an 8 a.m. class,” says Avellone, who juggles school and a job at Northwestern University.

During finals, she stayed awake 40 consecutive hours by chain-smoking and drinking coffee so she could write two papers, she says. She received a top score on the first one, but is not sure if she fared as well on the second.

“I'm big on procrastinating,” Avellone says. “My intentions at the beginning of the school year are not to procrastinate and work as hard as possible, but it never ends up that way. This is just the way to get my work done.”


–Your memory: A recent study says that during the nondreaming portion of sleep, the brain replays the day, which helps people reflect on events and how to learn from them. Information crammed over a sleepless night has less chance of sticking.

–Best way to take advantage: Intersperse sleep between periods of wakefulness in a regular way.

–Long-term sleep deprivation: Can lead to chronic fatigue, depressed moods, irritability, headaches and weight gain.

© 2007, Chicago Tribune.

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