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By Rick Nauert PhD Senior News Editor
Reviewed by John M. Grohol, Psy.D. on April 23, 2010


The evidence continues to mount that successful study habits should include plenty of napping.


Researchers report people who take a nap and dream about a task they’ve just learned perform it better upon waking than either those who don’t sleep at all or those who sleep but don’t report any associated dreams.


The study is found online in Current Biology, a Cell Press publication.


The learners in the study were asked to sit in front of a computer screen and learn the layout of a three-dimensional maze so that they could find their way to a landmark (a tree) when they were plopped down at a random location within the virtual space five hours later.


Those who were allowed to take a nap and also remembered dreaming of the task found the tree in less time.


“We at first thought that dreaming must reflect the memory process that’s improving performance,” said Robert Stickgold of Harvard Medical School.


“But when you look at the content of the dreams, it was hard to argue that.”


In a couple of cases, the dreamers said they recalled just the music from the computer maze. One subject said they were dreaming that there were people at particular checkpoints in the maze, even though the real maze didn’t have any people or checkpoints.


Another said they dreamed about an experience they’d had tromping through bat caves and thinking that the caves were like mazes.


“We think that the dreams are a marker that the brain is working on the same problem at many levels,” Stickgold said.


“The dreams might reflect the brain’s attempt to find associations for the memories that could make them more useful in the future.”


In other words, it’s not that the dreams led to better memory, but rather that they are a sign that other, unconscious parts of the brain were working hard to remember how to get through the virtual maze. The dreams are essentially a side effect of that memory process.


Stickgold said that there may still be ways to take advantage of this phenomenon for improving learning and memory.


For instance, it may be better to study hard right before you go to sleep than in the afternoon, or to take a nap after a period of intense afternoon study.


More generally, people might take notice of the study habits or mental processes while awake that lead them to dream about something they need to remember.


Perhaps other more directed ways to guide dreams could even prove useful to make your brain work on what you want it to at night.


But, Stickgold said, the most exciting thing to him is the notion that this line of evidence might elucidate a deeper question that has seemed almost impossible to tackle: Why do we dream? What is its function?


“Some have viewed dreaming as entertainment, but this study suggests it is a by-product of memory processing,” he said.


Whether you have to remember your dreams to get the benefits isn’t yet entirely clear, but Stickgold suspects not. After all, he said, people generally remember only a small fraction, no more than 10 to 15 percent, of their dreams.


The researchers hope to follow up their study by manipulating the learning environment in ways that boost incorporation into dreams. They also plan to study the same phenomenon following a full night of sleep as opposed to a nap.


Source: Cell Press


http://psychcentral.com/news/2010/04/23/naps-and-dreams-help-academics/13116.html


The Secrets of Sleep


From birth, we spend a third of our lives asleep. After decades of research, we’re still not sure why.


By D. T. Max


Cheryl Dinges is a 29-year-old Army sergeant from St. Louis. Her job is to train soldiers in hand-to-hand combat. Specializing in Brazilian jujitsu, Dinges says she is one of the few women in the Army certified at level 2 combat. Level 2 involves a lot of training with two attackers on one, she explains, with the hope of “you being the one guy getting out alive.”


Dinges may face an even harder fight in the years ahead. She belongs to a family carrying the gene for fatal familial insomnia. The main symptom of FFI, as the disease is often called, is the inability to sleep. First the ability to nap disappears, then the ability to get a full night’s sleep, until the patient cannot sleep at all. The syndrome usually strikes when the sufferer is in his or her 50s, ordinarily lasts about a year, and, as the name indicates, always ends in death. Dinges has declined to be tested for the gene. “I was afraid that if I knew that this was something I had, I would not try as hard in life. I would allow myself to give up.”


FFI is an awful disease, made even worse by the fact that we know so little about how it works. After years of study, researchers have figured out that in a patient with FFI, malformed proteins called prions attack the sufferer’s thalamus, a structure deep in the brain, and that a damaged thalamus interferes with sleep. But they don’t know why this happens, or how to stop it, or ease its brutal symptoms. Before FFI was investigated, most researchers didn’t even know the thalamus had anything to do with sleep. FFI is exceedingly rare, known in only 40 families worldwide. But in one respect, it’s a lot like the less serious kinds of insomnia plaguing millions of people today: It’s pretty much a mystery.


If we don’t know why we can’t sleep, it’s in part because we don’t really know why we need to sleep in the first place. We know we miss it if we don’t have it. And we know that no matter how much we try to resist it, sleep conquers us in the end. We know that seven to nine hours after giving in to sleep, most of us are ready to get up again, and 15 to 17 hours after that we are tired once more. We have known for 50 years that we divide our slumber between periods of deep-wave sleep and what is called rapid eye movement (REM) sleep, when the brain is as active as when we’re awake, but our voluntary muscles are paralyzed. We know that all mammals and birds sleep. A dolphin sleeps with half its brain awake so it can remain aware of its underwater environment. When mallard ducks sleep in a line, the two outermost birds are able to keep half of their brains alert and one eye open to guard against predators. Fish, reptiles, and insects all experience some kind of repose too.


All this downtime comes at a price. An animal must lie still for a great stretch of time, during which it is easy prey for predators. What can possibly be the payback for such risk? “If sleep doesn’t serve an absolutely vital function,” the renowned sleep researcher Allan Rechtschaffen once said, “it is the greatest mistake evolution ever made.”


Read More:  http://ngm.nationalgeographic.com/2010/05/sleep/max-text



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