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By Roni Caryn Rabin Melatonin has been shown to be effective in randomized clinical trials — the kind considered the gold standard in medicine — but it may work better for some sleep problems than others. “There is pretty strong evidence it’s effective for jet lag,” said D. Craig Hopp, a program director at the National Center for Complementary and Integrative Health, part of the National Institutes of Health. But “the evidence is more equivocal for chronic things like insomnia.” A 2002 Cochrane review that analyzed 10 randomized trials, most of them comparing oral melatonin to placebo, concluded that melatonin is “remarkably effective in preventing or reducing jet lag.” It not only helped people fall asleep faster and sleep more soundly, but also led to less daytime fatigue and improved general well-being. Eight of the 10 trials found that taking melatonin for several days after arriving at a destination reduced jet lag from flights crossing at least five time zones. In many of the trials, people also took melatonin on the day of the flight or for several days before the trip, usually in the late afternoon or early evening. Once at the destination, melatonin should be taken close to bedtime, aiming for the local hours between 10 p.m. and midnight. Doses of 0.5 milligrams and 5 milligrams were both effective, though people fell asleep faster and slept better with the larger dose. For others with insomnia, melatonin has more modest benefits. A 2013 analysis that looked at 19 randomized controlled trials involving 1,683 subjects determined that on average, melatonin reduced the amount of time it took to fall asleep by seven minutes when compared with placebo and increased total sleep time by eight minutes. © 2015 The New York Times Company

Related chapters from BP7e: Chapter 14: Biological Rhythms, Sleep, and Dreaming; Chapter 5: Hormones and the Brain
Related chapters from MM:Chapter 10: Biological Rhythms and Sleep; Chapter 8: Hormones and Sex
Link ID: 21734 - Posted: 12.30.2015

Need to remember something important? Take a break. A proper one – no TV or flicking through your phone messages. It seems that resting in a quiet room for 10 minutes without stimulation can boost our ability to remember new information. The effect is particularly strong in people with amnesia, suggesting that they may not have lost the ability to form new memories after all. “A lot of people think the brain is a muscle that needs to be continually stimulated, but perhaps that’s not the best way,” says Michaela Dewar at Heriot-Watt University in Edinburgh, UK. New memories are fragile. They need to be consolidated before being committed to long-term storage, a process thought to happen while we sleep. But at least some consolidation may occur while we’re awake, says Dewar – all you need is a timeout. In 2012, Dewar’s team showed that having a rest helps a person to remember what they were told a few minutes earlier. And the effect seems to last. People who had a 10-minute rest after hearing a story remembered 10 per cent more of it a week later than those who played a spot-the-difference game immediately afterwards. “We dim the lights and ask them to sit in an empty, quiet room, with no mobile phones,” says Dewar. When asked what they had been thinking about afterwards, most volunteers said they had let their minds wander. Now Dewar, along with Michael Craig at the University of Edinburgh and their colleagues, have found that spatial memories can also be consolidated when we rest. © Copyright Reed Business Information Ltd.

Related chapters from BP7e: Chapter 14: Biological Rhythms, Sleep, and Dreaming; Chapter 17: Learning and Memory
Related chapters from MM:Chapter 10: Biological Rhythms and Sleep; Chapter 13: Memory, Learning, and Development
Link ID: 21721 - Posted: 12.24.2015

Rae Ellen Bichell Ever notice the catnaps that older relatives take in the middle of the day? Or how grandparents tend to be early risers? You're not alone. Colleen McClung did, too. A neuroscientist at the University of Pittsburgh Medical Center, McClung wanted to know what was going on in the brain that changes people's daily rhythms as they age. We all have a set of so-called clock genes that keep us on a 24-hour cycle. In the morning they wind us up, and at night they help us wind down. A study out Monday in Proceedings of the National Academy of Sciences found that those genes might beat to a different rhythm in older folks. "When you think about the early bird dinner specials, it sort of fits in with their natural shift in circadian rhythms," says McClung. "There is a core set of genes that has been described in every animal — every plant all the way down from fungus to humans — and they're pretty much the same set of genes." The genes are the master controllers of a bunch of other genes that control processes ranging from metabolism to sleep. When you woke up this morning, the timekeeping genes told a gland in your brain to give a jolt of the stress hormone cortisol to wake up. Tonight, they'll tell a gland to spit out melatonin, a hormone that makes you sleepy. "You can think of them as sort of the conductor of an orchestra," says McClung. They make sure all the other genes keep time. © 2015 npr

Related chapters from BP7e: Chapter 14: Biological Rhythms, Sleep, and Dreaming; Chapter 7: Life-Span Development of the Brain and Behavior
Related chapters from MM:Chapter 10: Biological Rhythms and Sleep; Chapter 13: Memory, Learning, and Development
Link ID: 21717 - Posted: 12.22.2015

Carl Zimmer Over the past few million years, the ancestors of modern humans became dramatically different from other primates. Our forebears began walking upright, and they lost much of their body hair; they gained precision-grip fingers and developed gigantic brains. But early humans also may have evolved a less obvious but equally important advantage: a peculiar sleep pattern. “It’s really weird, compared to other primates,” said Dr. David R. Samson, a senior research scientist at Duke University. In the journal Evolutionary Anthropology, Dr. Samson and Dr. Charles L. Nunn, an evolutionary biologist at Duke, reported that human sleep is exceptionally short and deep, a pattern that may have helped give rise to our powerful minds. Until recently, scientists knew very little about how primates sleep. To document orangutan slumber, for example, Dr. Samson once rigged up infrared cameras at the Indianapolis Zoo and stayed up each night to watch the apes nod off. By observing their movements, he tracked when the orangutans fell in and out of REM sleep, in which humans experience dreams. “I became nocturnal for about seven months,” Dr. Samson said. “It takes someone who wants to get their Ph.D. to be motivated enough to do that.” In the new study. Dr. Samson and Dr. Nunn combined that information with studies of 19 other primate species. The researchers found wide variations in how long the animals slept. Mouse lemurs doze for seventeen hours a day, for example, while humans sleep just seven hours or so a day — “the least of any primate on the planet,” said Dr. Samson. © 2015 The New York Times Company

Related chapters from BP7e: Chapter 14: Biological Rhythms, Sleep, and Dreaming; Chapter 6: Evolution of the Brain and Behavior
Related chapters from MM:Chapter 10: Biological Rhythms and Sleep
Link ID: 21712 - Posted: 12.19.2015

By Karen Weintraub Is sleep induced by a benzodiazepine counted as restorative sleep? Researchers hate to admit it, but they don’t know enough about sleep to answer this question. Their best guess, several experts said, is that sleep is sleep. Dr. John Weyl Winkelman, a sleep disorders expert at Massachusetts General Hospital and Harvard Medical School, said if a patient asked him whether medicated sleep was restorative, “I’d say: ‘You tell me.’” There is quite a bit of evidence about the negative health consequences of insomnia, but researchers don’t know precisely what it is in the brain and body that is "restored" by sleep to aid optimal function. And it is unlikely that any specific stage of sleep is uniquely restorative, said Dr. Daniel J. Buysse, a sleep medicine expert and professor of psychiatry at the University of Pittsburgh. More sleep, less interrupted sleep, and sleep at the right time of night are all likely to be important, he said. There are two types of sleep: REM, when people dream, and non-REM, which has light, medium and deep portions. Sleeping pills mainly increase the amount of medium-depth non-REM sleep, Dr. Buysse said. Medications can help people fall asleep faster and reduce nighttime wakefulness, he said, and those changes are usually considered to contribute to restorative sleep. But different people respond differently. “Do you feel more rested, more alert, more able to concentrate, less irritable on medication versus off?" Dr. Buysse said. "If all those things are true then I would say it’s more restorative. If a hypnotic drug leaves you feeling hung over or more anxious, if it causes you to order five hickory smoked turkeys on the Internet without remembering, then it’s probably not good.” © 2015 The New York Times Company

Related chapters from BP7e: Chapter 14: Biological Rhythms, Sleep, and Dreaming; Chapter 4: The Chemistry of Behavior: Neurotransmitters and Neuropharmacology
Related chapters from MM:Chapter 10: Biological Rhythms and Sleep; Chapter 4: The Chemistry of Behavior: Neurotransmitters and Neuropharmacology
Link ID: 21691 - Posted: 12.12.2015

By Nicholas Bakalar Several studies have shown that there is an association between shift work and an increased risk for heart disease and diabetes. Now a new study, in the Journal of Clinical Endocrinology & Metabolism, has found a similar association in people whose sleeping schedules change on the weekend. For seven days, 447 men and women ages 30 to 54 wore devices that measured movement and tracked when they fell asleep and woke. Almost 85 percent of the group went to sleep and woke later on their days off than during the workweek. The researchers found that the greater the mismatch in sleep timing between weekdays and weekends, the higher the metabolic risk. Sleeping late on days off was linked to lower HDL (good) cholesterol, higher triglycerides, higher insulin resistance and higher body mass index. The associations persisted after controlling for physical activity, caloric intake, alcohol use and other factors. “It’s not clear yet that this is a long-term effect,” said the lead author, Patricia M. Wong, a graduate student at the University of Pittsburgh. “But we think of this as people having to sleep and work out of sync with their internal clock, and that having to be out of sync may be having these health effects.” © 2015 The New York Times Company

Related chapters from BP7e: Chapter 14: Biological Rhythms, Sleep, and Dreaming
Related chapters from MM:Chapter 10: Biological Rhythms and Sleep
Link ID: 21651 - Posted: 11.21.2015

By Rachel E. Gross For decades, Michael Jackson had struggled to fall asleep at night. But in 2009 the pop singer was preparing for his worldwide comeback tour, and he couldn’t afford to be at anything less than 100 percent. Desperate for sleep, he convinced an unscrupulous physician to give it to him synthetically in the form of an anesthetic so strong that it sent him almost immediately into a “druglike coma.” At first, Jackson would wake up feeling refreshed. But the nightly injections conferred only the shadow of true sleep, with none of the deep, dream-filled REM cycles that his body needed. Soon he was fading fast, his mind and mood slipping away. Within two months Jackson was dead of an overdose. If that hadn’t killed him, doctors later testified during his wrongful death trial, he would have died of sleep deprivation. Jackson’s is a particularly dramatic case. But his struggle for oblivion rings true to anyone who has dealt with insomnia. “I’m for anything that gets you through the night,” Frank Sinatra once said, “be it prayer, tranquilizers, or a bottle of Jack Daniel’s.” If you have insomnia, you’ll understand this sentiment, and you’re not alone: Regular sleep eludes up to 15 percent of the population, making insomnia the most commonly diagnosed sleep problem in America. Fortunately, the nighttime affliction is becoming steadily less mysterious—at least from the perspective of neuroscience. While insomniacs toss and turn, researchers are finally starting to understand this elusive disease. As it turns out, chronic insomnia may be more hard-wired into our brains than we had thought, and indicative of larger differences that separate the brains of the sleepless from those who so effortlessly enter the land of dreams. © 2015 The Slate Group LLC

Related chapters from BP7e: Chapter 14: Biological Rhythms, Sleep, and Dreaming
Related chapters from MM:Chapter 10: Biological Rhythms and Sleep
Link ID: 21614 - Posted: 11.07.2015

By Jan Hoffman As the first semester of the school year reaches the halfway mark, countless college freshmen are becoming aware that their clothes are feeling rather snug. While the so-called freshman 15 may be hyperbole, studies confirm that many students do put on five to 10 pounds during that first year away from home. Now new research suggests that an underlying cause for the weight gain may be the students’ widely vacillating patterns of sleep. A study in the journal Behavioral Sleep Medicine looked at the sleep habits of first-semester freshmen. Researchers followed 132 first-year students at Brown University who kept daily sleep diaries. After nine weeks, more than half of them had gained nearly six pounds. There are many poor sleep habits that might have exacerbated their weight gains, a growing body of research indicates. Was it abbreviated sleep? Optimally, experts say, teenagers need about nine hours and 15 minutes a night. These freshmen averaged about seven hours and 15 minutes. In a study earlier this year, in the journal PLOS One, researchers found that when teenagers are sleep-deprived, they more readily reach for candy and desserts. Or were the Brown students’ late bedtimes the scale-tipping factor? On average, they went to bed around 1:30 a.m. A study this month in the journal Sleep that followed teenagers into adulthood found that each hour later bedtime was pushed during the school or workweek was associated with about a two-point increase in body mass index. While both the amount of sleep and the lateness of bedtime may have played a role, the researchers in the Brown study identified a new sleep factor for predicting weight gain: variability, or the extent to which a student’s bedtime and waking time changed daily. © 2015 The New York Times Company

Related chapters from BP7e: Chapter 14: Biological Rhythms, Sleep, and Dreaming; Chapter 13: Homeostasis: Active Regulation of the Internal Environment
Related chapters from MM:Chapter 10: Biological Rhythms and Sleep; Chapter 9: Homeostasis: Active Regulation of the Internal Environment
Link ID: 21573 - Posted: 10.27.2015

By Nicholas Bakalar A new study has found that sleep apnea is associated with an increased risk for gout, a painful disease of the big toe and other joints caused by elevated levels of uric acid in the blood. Observational studies have shown that people with sleep apnea have a higher prevalence of excess uric acid, but until now it has been unclear whether sleep apnea is associated with gout, and how strongly. Using records in a British health database, researchers studied 9,865 people, average age 54, with sleep apnea and matched them to 43,598 controls without the disorder. Because sleep apnea is associated with being overweight, the participants were matched for B.M.I., among many other characteristics. The study is in Arthritis & Rheumatology. After one year, compared with controls, people with sleep apnea were about 50 percent more likely to have had an attack of gout, and the increased risk was found without regard to sex, age or obesity. The conclusion suggests that treating sleep apnea would reduce gout attacks, but the lead author, Yuqing Zhang, a professor of medicine at Boston University, is cautious. “Our findings call for future studies to evaluate the effect of treating sleep apnea on serum uric acid levels and the risk of gout,” he said. © 2015 The New York Times Company

Related chapters from BP7e: Chapter 14: Biological Rhythms, Sleep, and Dreaming
Related chapters from MM:Chapter 10: Biological Rhythms and Sleep
Link ID: 21563 - Posted: 10.26.2015

By Jonathan Webb Science reporter, BBC News Crocodiles can sleep with one eye open, according to a study from Australia. In doing so they join a list of animals with this ability, which includes some birds, dolphins and other reptiles. Writing in the Journal of Experimental Biology, the researchers say the crocs are probably sleeping with one brain hemisphere at a time, leaving one half of the brain active and on the lookout. Consistent with this idea, the crocs in the study were more likely to leave one eye open in the presence of a human. They also kept that single eye trained directly on the interloper, said senior author John Lesku. "They definitely monitored the human when they were in the room. But even after the human left the room, the animal still kept its open eye… directed towards the location where the human had been - suggesting that they were keeping an eye out for potential threats." The experiments were done in an aquarium lined with infrared cameras, to monitor juvenile crocodiles day and night. "These animals are not particularly amenable to handling; they are a little snippy. So we had to limit all of our work to juvenile crocodiles, about 40-50cm long," said Dr Lesku, from La Trobe University in Melbourne. As well as placing a human in the room for certain periods, the team tested the effect of having other young crocs around. Sure enough, these also tended to attract the gaze of any reptiles dozing with only one eye. This matches what is known of "unihemispheric sleep" in aquatic mammals, such as walruses and dolphins, which seem to use one eye to make sure they stick together in a group. © 2015 BBC.

Related chapters from BP7e: Chapter 14: Biological Rhythms, Sleep, and Dreaming; Chapter 19: Language and Hemispheric Asymmetry
Related chapters from MM:Chapter 10: Biological Rhythms and Sleep; Chapter 15: Brain Asymmetry, Spatial Cognition, and Language
Link ID: 21548 - Posted: 10.22.2015

By Nicholas Bakalar Sleep apnea may be even more dangerous for women than for men, a new study suggests. Epidemiological studies have linked sleep apnea to heart disease in men, but the differences in risk between men and women have been largely unexplored. For the current study, researchers measured sleep quality electronically in 737 men and 879 women, average age 63, who were free of cardiovascular disease at the start of the study. They also tested all of them for troponin T, a protein that can be released into the bloodstream if the heart is damaged, and whose presence in otherwise healthy people indicates an increased risk for heart disease. They tracked the participants for 14 years, recording incidents of coronary artery disease, heart failure and death from cardiovascular disease or other causes. The study was published in Circulation. Obstructive sleep apnea was independently associated with increased troponin T, heart failure and death in women, but not in men. And in women, but not men, sleep apnea was associated with an enlarged heart, another risk factor for cardiovascular disease. “Most people who have sleep apnea have a lot of other risks for heart disease,” said the lead author, Dr. Amil M. Shah, an assistant professor of medicine at Harvard. “But in women, the relationship between sleep apnea and heart disease persisted even after accounting for the other risks.” “Even among women with sleep apnea who don’t get heart failure,” he continued, “it’s associated with changes in the heart that lead to worse outcomes.” © 2015 The New York Times Company

Related chapters from BP7e: Chapter 14: Biological Rhythms, Sleep, and Dreaming; Chapter 12: Sex: Evolutionary, Hormonal, and Neural Bases
Related chapters from MM:Chapter 10: Biological Rhythms and Sleep; Chapter 8: Hormones and Sex
Link ID: 21547 - Posted: 10.22.2015

By Anahad O'Connor For years, public health authorities have warned that smartphones, television screens and the hectic pace of modern life are disrupting natural sleep patterns, fueling an epidemic of sleep deprivation. By some estimates, Americans sleep two to three hours fewer today than they did before the industrial revolution. But now a new study is challenging that notion. It found that Americans on average sleep as much as people in three different hunter-gatherer societies where there is no electricity and the lifestyles have remained largely the same for thousands of years. If anything, the hunter-gatherer communities included in the new study — the Hadza and San tribes in Africa, and the Tsimané people in South America — tend to sleep even less than many Americans. The findings are striking because health authorities have long suggested that poor sleep is rampant in America, and that getting a minimum of seven hours on a consistent basis is a necessity for good health. Many studies suggest that lack of sleep, independent of other factors like physical activity, is associated with obesity and chronic disease. Yet the hunter-gatherers included in the new study, which was published in Current Biology, were relatively fit and healthy despite regularly sleeping amounts that are near the low end of those in industrialized societies. Previous research shows that their daily energy expenditure is about the same as most Americans, suggesting physical activity is not the reason for their relative good health. The prevailing notion in sleep medicine is that humans evolved to go to bed when the sun goes down, and that by and large we stay up much later than we should because we are flooded with artificial light, said Jerome Siegel, the lead author of the new study and a professor of psychiatry at the Semel Institute of Neuroscience and Human Behavior at U.C.L.A. © 2015 The New York Times Company

Related chapters from BP7e: Chapter 14: Biological Rhythms, Sleep, and Dreaming
Related chapters from MM:Chapter 10: Biological Rhythms and Sleep
Link ID: 21523 - Posted: 10.17.2015

Chris Samoray People in the postindustrial world don’t always get a sound night sleep. But they appear to spend a similar amount of time sleeping as do people in hunter-gatherer communities in Africa and South America, a new study finds. “It’s absolutely clear that they don’t sleep more than we do,” says Jerome Siegel, a UCLA sleep scientist. In fact, on average, hunter-gatherers may sleep a little less. Recommended nightly sleep for adults is typically seven to nine hours; a 2013 Gallup poll showed that most Americans get around 6.8 hours. On most nights, members of three hunter-gatherer groups — the Hadza of Tanzania, the Ju/’hoansi San of Namibia and the Tsimane of Bolivia — sleep 5.7 to 7.1 hours, Siegel and colleagues report online October 15 in Current Biology. That’s on the lower end of the sleep spectrum in postindustrial societies, the researchers say. Evidence from the new study also suggests that these groups experience less insomnia than sleepers in postindustrial societies. (The three hunter-gatherer languages even lack a word for insomnia.) Hunter-gatherer sleep patterns are closely tied to temperature, a new study shows. Among the Hadza of Tanzania, for instance, people fell asleep about three hours after sunset, on average, as ambient temperatures decreased. People then woke up about an hour before sunrise, when temperatures reached their lowest point. © Society for Science & the Public 2000 - 2015.

Related chapters from BP7e: Chapter 14: Biological Rhythms, Sleep, and Dreaming
Related chapters from MM:Chapter 10: Biological Rhythms and Sleep
Link ID: 21520 - Posted: 10.16.2015

Joe Palca Mothers have been warned for years that sleeping with their newborn infant is a bad idea because it increases the risk the baby might die unexpectedly during the night. But now Israeli researchers are reporting that even sleeping in the same room can have negative consequences: not for the child, but for the mother. Researchers at Ben-Gurion University of the Negev wanted to see whether sleeping in the same room as their newborn affected mothers' or babies' sleep. The short answer: It did, and the effect wasn't good for moms. The researchers recruited 153 married couples expecting their first child to participate in the study. The new parents weren't told where or how to sleep. They were simply asked to record whether they slept in the same room as their newborn, the same bed and same room, or if the child slept in another room. To measure sleep patterns, both mom and baby wore wristbands designed to measure movement during the night, a measurement that gives a pretty accurate indication of sleep patterns for both mother and child. The researchers measured sleep patterns before the babies were born, at 3 months and at 6 months. Mothers who slept in the same room as their infants, whether in the same bed or just the same room, had poorer sleep than mothers whose babies slept elsewhere in the house: They woke up more frequently (approximately three times per night versus two), were awake approximately 20 minutes longer per night, and had shorter periods of uninterrupted sleep (approximately 136 minutes versus 166 minutes). These results held true even taking into account that many of the women in the study were breast-feeding their babies. © 2015 NPR

Related chapters from BP7e: Chapter 14: Biological Rhythms, Sleep, and Dreaming
Related chapters from MM:Chapter 10: Biological Rhythms and Sleep
Link ID: 21468 - Posted: 10.03.2015

Dark puffy eyes, a feeling of deep exhaustion, and a foul mood to match – we’ve all experienced the side effects of a lack of sleep. It’s no wonder that sleep-deprivation has been used as a method of torture. Our brains seem to lose the ability to distinguish between the innocuous and emotional in such circumstances, turning us into overreacting, exhausted wrecks. We all know that a good night’s sleep is vital for a day of clear thinking, but exactly why sleep is so important remains a mystery. Talma Hendler of Tel Aviv University in Israel is particularly interested in how lack of sleep leaves us with a short emotional fuse. “We know that sleep affects our emotional behaviour, but we don’t know how,” she says. To investigate further, Hendler and her colleagues kept 18 adults awake all night. “It took a great effort,” she says. “During the night, we repeatedly measured their sleepiness, and unsurprisingly they got more and more tired.” The volunteers were put through two rounds of tests while their brains were scanned, both the day after a good night’s sleep and after being awake for 24 hours. In one test, volunteers were asked to give the direction in which yellow dots moved on a screen. In each case, the dots were laid over a potentially distracting picture that was either positively emotional (of a kitten or a couple in love, for example), negatively emotional (such as a mutilated body or a snake) or neutral (such as a cow or spoon). © Copyright Reed Business Information Ltd.

Related chapters from BP7e: Chapter 14: Biological Rhythms, Sleep, and Dreaming; Chapter 15: Emotions, Aggression, and Stress
Related chapters from MM:Chapter 10: Biological Rhythms and Sleep; Chapter 11: Emotions, Aggression, and Stress
Link ID: 21445 - Posted: 09.26.2015

By C. CLAIBORNE RAY A. Wild canines that rely on strenuous hunting to survive may sleep or rest as much as, or even more than, indolent human-created breeds that rely on a can or a bag of kibble. Domestic dogs, with their great range of body types and personalities, show a tremendous variety of sleep patterns, often including relatively brief periods of deep sleep spread out over several hours. A half-century-long study of wolves and their interaction with their prey on Isle Royale, a wilderness island in Lake Superior, found that in winter the wolves would feed for hours on a fresh kill, then sprawl out or curl up in the snow and rest or sleep about 30 percent of the time. “Wolves have plenty of reason to rest,” the study’s researchers wrote. “When wolves are active, they are really active. On a daily basis, wolves burn about 70 percent more calories compared to typical animals of similar size.” The researchers note that while hunting, wolves may burn calories at 10 to 20 times the rate they do while resting. “When food is plentiful, wolves spend a substantial amount of time simply resting, because they can,” the study said. “When food is scarce, wolves spend much time resting because they need to.” Wolves may eat only once every five to 10 days, the researchers said, losing as much as 8 to 10 percent of body weight, but regaining all the lost weight in just two days of eating and resting. © 2015 The New York Times Company

Related chapters from BP7e: Chapter 14: Biological Rhythms, Sleep, and Dreaming
Related chapters from MM:Chapter 10: Biological Rhythms and Sleep
Link ID: 21419 - Posted: 09.20.2015

By Barbara S. Moffet It’s 1 in the morning and I’ve been in bed for a few hours now. Maybe it’s the few drops of caffeine I mistakenly drank earlier in the day. Or perhaps it’s the 26 wires that are attached to my scalp, face, finger and legs and the strap pulled taut around my waist. All I know is I’m not doing what you’re supposed to do in a sleep lab, and if I don’t fall asleep soon, it’ll be time to take off my pajamas and go home. I’m here because my doctor thought it was time to find out what was causing a cluster of possibly sleep-related health issues: snoring, frequent middle-of-the-night waking and some problems with concentrating that I’ve had most of my 63 years. I also have a genetic condition, Ehler-Danlos syndrome, that can cause airways to partially close during sleep. I’ve landed at Sleep Centers of Northern Virginia in Alexandria, one of at least two dozen sleep labs in the area. According to the National Institutes of Health, some 70 million Americans are “poor sleepers,” and the ramifications of inadequate shut-eye can range from grumpiness and lack of focus to heart disease, diabetes, high blood pressure and even a diminished life expectancy. Research published this year in the journal Neurology concluded that people with sleep apnea — a disorder that causes a person to repeatedly stop breathing during the night, rousing them from sleep — developed problems with cognition about 10 years earlier than other people.

Related chapters from BP7e: Chapter 14: Biological Rhythms, Sleep, and Dreaming
Related chapters from MM:Chapter 10: Biological Rhythms and Sleep
Link ID: 21409 - Posted: 09.15.2015

John Peever, and Brian J. Murray, The function of sleep has mystified scientists for thousands of years, but modern research is providing new clues about what it does for both the mind and body. Sleep serves to reenergize the body's cells, clear waste from the brain, and support learning and memory. It even plays vital roles in regulating mood, appetite and libido. Sleeping is an integral part of our life, and as research shows, it is incredibly complex. The brain generates two distinct types of sleep—slow-wave sleep (SWS), known as deep sleep, and rapid eye movement (REM), also called dreaming sleep. Most of the sleeping we do is of the SWS variety, characterized by large, slow brain waves, relaxed muscles and slow, deep breathing, which may help the brain and body to recuperate after a long day. When we fall asleep, the brain does not merely go offline, as implied by the common phrase “out like a light.” Instead a series of highly orchestrated events puts the brain to sleep in stages. Technically sleep starts in the brain areas that produce SWS. Scientists now have concrete evidence that two groups of cells—the ventrolateral preoptic nucleus in the hypothalamus and the parafacial zone in the brain stem—are involved in prompting SWS. When these cells switch on, it triggers a loss of consciousness. After SWS, REM sleep begins. This mode is bizarre: a dreamer's brain becomes highly active while the body's muscles are paralyzed, and breathing and heart rate become erratic. The purpose of REM sleep remains a biological mystery, despite our growing understanding of its biochemistry and neurobiology. © 2015 Scientific American

Related chapters from BP7e: Chapter 14: Biological Rhythms, Sleep, and Dreaming
Related chapters from MM:Chapter 10: Biological Rhythms and Sleep
Link ID: 21408 - Posted: 09.15.2015

Patricia Neighmond Are you getting enough sleep, or not enough? If your answer to either of these questions is "yes," you may be at risk of heart disease. Just the right amount of good-quality sleep is key to good heart health, according to researchers at the Center for Cohort Studies at Kangbuk Samsung Hospital and Sungkyunkwan University School of Medicine in Seoul, South Korea. Poor sleep habits may put you at higher risk for early signs of heart disease, even at a relatively young age. The researchers studied more than 47,000 young and middle-aged men and women, average age around 41, who answered questions about how long and how well they slept. Then they had tests to measure their cardiovascular health. Early coronary lesions were detected by measuring the amount of calcium in the arteries of the heart. Stiffness of arteries was measured by the speed of blood coursing through the arteries in the upper arm and ankle. Calcium buildup and arterial stiffness are two important warning signs of oncoming heart disease. Findings showed that adults who slept less than five hours a night had 50 percent more calcium in their coronary arteries than those who slept seven hours. Those who slept nine hours or more a night had even worse outcomes, with 70 percent more coronary calcium compared to those who slept seven hours. © 2015 NPR

Related chapters from BP7e: Chapter 14: Biological Rhythms, Sleep, and Dreaming
Related chapters from MM:Chapter 10: Biological Rhythms and Sleep
Link ID: 21406 - Posted: 09.14.2015

Ian Sample Science editor People who get too little sleep are more likely to catch a cold, according to US scientists who suspect that a good night’s sleep is crucial for the body’s immune defences. Those who slept six hours a night or less were four times more likely to catch a cold when they were exposed to the virus than people who spent more than seven hours a night asleep, their study found. The findings, reported in the journal Sleep, build on previous studies that suggest that the sleep-deprived are more susceptible to infectious diseases and recover more slowly when they do fall ill. “It goes beyond feeling groggy or irritable,” said Aric Prather, a health psychologist at the University of California in San Francisco. “Not getting enough sleep affects your physical health.” The scientists recruited 94 men and 70 women, with an average age of 30, for the study and subjected them to two months of health screening, interviews and questionnaires to establish their baseline stress levels, temperament and usage of alcohol and tobacco. The volunteers then spent a week wearing a wrist-mounted sleep sensor that tracked the duration and quality of their sleep each night. To see how well they fought off infections, the participants were taken to a hotel and given nasal drops containing the cold virus. Doctors monitored them closely for a week after, collecting mucus samples to work out if and when the virus took hold. © 2015 Guardian News and Media Limited

Related chapters from BP7e: Chapter 14: Biological Rhythms, Sleep, and Dreaming; Chapter 15: Emotions, Aggression, and Stress
Related chapters from MM:Chapter 10: Biological Rhythms and Sleep; Chapter 11: Emotions, Aggression, and Stress
Link ID: 21371 - Posted: 09.01.2015