Chapter 14. Biological Rhythms, Sleep, and Dreaming

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By C. Claiborne Ray Q. Do lizards dream like people do? A. Some species of lizards do have two sleep phases, one resembling the dreaming phase of human beings, other mammals and birds. In 2016, a study of the central bearded dragon, Pogona vitticeps, found slow-wave and rapid-eye-movement states that cycled back and forth in 80-second increments over sleep periods of six to 10 hours. In other animals, slow-wave sleep is usually described as deep, dreamless sleep, while rapid eye movements are linked to shallower sleep and dreaming. Recently scientists in France collected data on brain activity, heart rates and behavioral patterns, including eye movement, in the sleeping Argentine black-and-white tegu (Salvator merianae). The scientists also documented two sleep states, suggesting that the animals do experience something like R.E.M. sleep. In both studies, the researchers suggested that dreaming may have originated with a common ancestor of mammals, birds and lizards, rather than developing independently in various species. © 2018 The New York Times Company

Keyword: Sleep; Evolution
Link ID: 25760 - Posted: 12.08.2018

By Nicholas Bakalar Getting enough sleep is healthful, but getting too much might not be. Researchers gathered health and lifestyle information, including self-reported sleep data, on 116,632 people in 21 countries. Over eight years of follow-up, they recorded 4,381 deaths and 4,365 major cardiovascular events. The study, in the European Heart Journal, found that compared with people who slept six to eight hours a night, those who slept eight to nine hours had a 5 percent increased risk for cardiovascular disease or death. People who slept nine to 10 hours had a 17 percent increased risk, and those who slept more than 10 hours increased their risk by 41 percent. The researchers also found a 9 percent increased risk in people who slept less than six hours, but that difference was not statistically significant. Daytime naps also increased the risk for cardiovascular events, but only in people who slept more than six hours a night. The researchers controlled for age, body mass index, physical activity, diabetes, depression, smoking, alcohol consumption and many other health and behavioral characteristics. “Get enough sleep — that is, six to eight hours a day,” said the lead author, Chuangshi Wang, a doctoral student at McMaster University in Hamilton, Ontario. “But if you sleep more than nine hours a day, you may want to visit a doctor to check your overall health.” © 2018 The New York Times Company

Keyword: Sleep
Link ID: 25750 - Posted: 12.06.2018

By Austin Frakt If part of a hospital stay is to recover from a procedure or illness, why is it so hard to get any rest? There is more noise and light than is conducive for sleep. And nurses and others visit frequently to give medications, take vitals, draw blood or perform tests and checkups — in many cases waking patients to do so. Some monitoring is necessary, of course. Medication must be given; some vital signs do need to be checked. And frequent monitoring is warranted for some patients — such as those in intensive care units. But others are best left mostly alone. Yet many hospitals don’t distinguish between the two, disrupting everyone on a predefined schedule. Peter Ubel understands the problem as both a physician and patient. When he spent a night in the hospital recovering from surgery in 2013, he was interrupted multiple times by blood draws, vital sign checks, other lab tests, as well as by the beeping of machines. “Not an hour went by without some kind of disruption,” said Dr. Ubel, a physician with Duke University. “It’s a terrible way to start recovery.” It’s more than annoying — such disruptions can harm patients. Short sleep durations are associated with reduced immune function, delirium, hypertension and mood disorders. Hospital conditions, including sleep disruptions, may contribute to “posthospital syndrome” — the period of vulnerability to a host of health problems after hospitalization that are not related to the reason for that hospitalization. “In addressing a patient’s acute illness, we may inadvertently be causing harm by ignoring the important restorative powers of a healing environment,” said Harlan Krumholz, a Yale University physician who has been calling attention to posthospital syndrome for several years. “The key to a successful recovery after illness may be a less stressful, more supportive, more humane experience during the hospitalization.” © 2018 The New York Times Company

Keyword: Sleep
Link ID: 25743 - Posted: 12.03.2018

Marshall Allen Last March, Tony Schmidt discovered something unsettling about the machine that helps him breathe at night. Without his knowledge, it was spying on him. From his bedside, the device was tracking when he was using it and sending the information not just to his doctor, but to the maker of the machine, to the medical supply company that provided it and to his health insurer. Schmidt, an information technology specialist from Carrollton, Texas, was shocked. "I had no idea they were sending my information across the wire." Schmidt, 59, has sleep apnea, a disorder that causes worrisome breaks in his breathing at night. Like millions of people, he relies on a continuous positive airway pressure, or CPAP, machine that streams warm air into his nose while he sleeps, keeping his airway open. Without it, Schmidt would wake up hundreds of times a night; then, during the day, he'd nod off at work, sometimes while driving and even as he sat on the toilet. "I couldn't keep a job," he recalls. "I couldn't stay awake." The CPAP, he says, saved his career, maybe even his life. As many CPAP users discover, the life-altering device comes with caveats: Health insurance companies are often tracking whether patients use them. If they aren't, the insurers might not cover the machines or the supplies that go with them. And, faced with the popularity of CPAPs — which can cost $400 to $800 — and their need for replacement filters, face masks and hoses, health insurers have deployed a host of tactics that can make the therapy more expensive or even price it out of reach. Patients have been required to rent CPAPs at rates that total much more than the retail price of the devices, or they've discovered that the supplies would be substantially cheaper if they didn't have insurance at all. © 2018 npr

Keyword: Sleep
Link ID: 25712 - Posted: 11.24.2018

By Perri Klass, M.D. More than 30 years ago, I went to a parent meeting at my oldest child’s day care center, when he was in the 2-year-old room, and it turned out that many of the children in the room were not reliably sleeping through the night. It felt like a revelation, discovering that mine was not the only child who occasionally — or regularly — woke in the night and needed some attention. In our family, we had come to terms with this, and we had managed to make — and generally keep — some rules: no food, no drink, no coming out of the crib, but yes, once a night one of your parents is willing to stagger down the hall, look in on you, rub your back and say something like, “We haven’t moved away and left you, now go back to sleep.” (Or maybe sometimes it was, “Go back to sleep or we will move away and leave you,” but that is lost in the mists of history.) It wasn’t ideal, but we were managing. In the current issue of the journal Pediatrics, researchers describe a study of almost 400 mothers in Canada who were asked to report: “During the night, how many consecutive hours does your child sleep without waking up?” The researchers took six or eight hours of uninterrupted sleep as definitions of “sleeping through the night.” They found that at 6 months of age, 62.4 percent of mothers reported that their infants slept for 6 hours or more at a stretch, and only 43 percent of the mothers reported eight-hour blocks of consecutive sleep. At 12 months, 72.1 percent of the mothers reported six hours of consecutive sleep, and 56.6 percent reported eight hours; since all infants wake several times a night, those who were reported as sleeping consecutively presumably awoke and went back to sleep by themselves without the mothers knowing it. So by these criteria, a significant number of the babies were not “sleeping through the night” at 6 months, and even at 12 months. At some time points, girls were more likely to sleep for longer periods than boys, but at other times there was no significant difference. © 2018 The New York Times Company

Keyword: Sleep; Development of the Brain
Link ID: 25698 - Posted: 11.19.2018

Adriana Galván Healthy sleep leads to healthy brains. Neuroscientists have gotten that message out. But parents, doctors and educators alike have struggled to identify what to do to improve sleep. Some have called for delaying school start times or limiting screentime before bed to achieve academic, health and even economic gains. Still, recent estimates suggest that roughly half of adolescents in the United States are sleep-deprived. These numbers are alarming because sleep is particularly important during adolescence, a time of significant brain changes that affect learning, self-control and emotional systems. And sleep deficits are even greater in economically disadvantaged youth compared to more affluent counterparts. Research from my developmental neuroscience lab shows one solution to the sleep deprivation problem that is deceptively simple: provide teens with a good pillow. Because getting comfortable bedding does not involve technology, expensive interventions or lots of time, it may be particularly beneficial for improving sleep among underresourced adolescents. Studies in my lab have shown that seemingly small differences in the quality and duration of sleep make a difference in how the brain processes information. Sleep acts like a glue that helps the brain encode recently learned information into long-term knowledge. It also improves focus in school because sleep helps dampen hyperactive behavior, strong emotional reactions and squirminess. This means that students who are normally dismissed from the classroom for disruptive behavior are more likely to stay in class if they’re not sleep-deprived. More time in the class leads to more learning. © 2010–2018, The Conversation US, Inc.

Keyword: Sleep; Development of the Brain
Link ID: 25681 - Posted: 11.14.2018

David DiSalvo Research findings suggesting that sleep loss and anxiety are closely linked were among those presented at Neuroscience 2018, the annual conference of the Society for Neuroscience held in San Diego, California. The news isn’t all dire, however – this year’s event offered some science-based encouragement along with causes for concern. Neuroscience continues focusing on the mysteries of sleep (and yes, it’s still plenty mysterious despite its media ubiquity)—not only the perils of failing to get enough, but the list of vital roles it plays in our brains. Research discussed at this year’s event touched on a range of findings, from sleep's roles in memory consolidation to garbage removal in brain tissue. We’re learning via more studies each year that sleep, including well-placed naps, facilitates the brain’s consolidation of information—moving memory freight from short-term to long-term storage, and sharpening its accessibility for when we need it. Without sleep, memory simply doesn’t happen. We’ve also learned that sleep provides the brain with an invaluable period of transporting toxins out of neural tissue through a complex garbage-removal system. Operating separately from the body's lymphatic system, the brain’s trash-disposal apparatus seems dependent on sleep to function properly. Links between neurodegenerative diseases like Alzheimer’s and the accumulation of toxins in brain tissue are exceptionally strong, and sleep loss is a likely culprit. A panel session at this year’s event called “Threats of Sleep Deprivation” highlighted new findings on the connection between sleep loss and anxiety. “Sleep deprivation isn’t what we usually think it is,” said session moderator Clifford Saper, MD, PhD of Harvard Medical School. It’s usually not “staying up 40 hours all at once,” but rather gradually losing sleep over time. ©2018 Forbes Media LLC.

Keyword: Sleep; Emotions
Link ID: 25680 - Posted: 11.14.2018

By Alice Robb One muggy Saturday last summer, I went on a date with a man who seemed entirely fine. We drank two beers and went for a walk, and he explained why he liked certain buildings that we passed. We kissed, and his breath tasted like cigarettes. We parted ways, and I couldn’t muster the energy to answer his emoji-laden follow-up texts about my weekend activities. The date was mediocre at best — but in the days that followed, I second-guessed my decision not to see him again. Maybe I had written him off too soon; maybe I should have given things a chance to develop. After all, he had some good qualities. He was handsome, tall, employed — and not, refreshingly, as a writer. It was only after a painfully on-the-nose dream a few weeks later that I stopped doubting my intuition. In the dream, I had agreed to a second date, and I had brought along two friends to observe our interactions and help me assess him. At the end of the group outing, my friends pulled me away and offered a unanimous decision: He wasn’t for me. I had made the right call. By the time we reach adulthood, most of us have accepted the conventional wisdom: We shouldn’t dwell on our dreams. Even though research suggests that REM sleep — when most dreaming takes place — is crucial for mental and physical health, we think of dreams as silly little stories, the dandruff of the brain. We’re taught that talking about our dreams is juvenile, self-indulgent, and that we should shake off their traces and get on with our day. It doesn’t have to be that way. For the past two years, a group of my friends has been gathering every month to talk about dreams; we do it for fun. Even if we resist, dreams have a way of sneaking into conscious territory and influencing our daytime mood. In three years of reporting on the science behind dreams, I’ve heard strangers describe flying, tooth loss, reunions with the dead — all the classics. I’ve seen that a dream can be a fascinating window into another person’s private life, and I’ve learned that paying attention to dreams can help us understand ourselves. © 2018 The New York Times Company

Keyword: Sleep; Attention
Link ID: 25672 - Posted: 11.12.2018

By Annette Choi “I was facing my clothes rack where I have a bunch of stuff hanging off of it,” Brandon Tan says. “And since it was dark, my bags and jackets were kind of morphed into black figures.” Tan, a New York City-based writer, says that that night—with eyes wide-open and lips sealed—he struggled to move his own body. Quickly, nightmarish hallucinations began taking over his auditory and sensory perceptions, blurring the line between dream and reality. “I just kept hearing really mischievous giggling and really creepy screaming,” he says. “And it felt like there were really strong gusts of wind in my room, but the window was completely shut.” Jackie Monoson can sympathize. But unlike Tan, who is new to the experience of sleep paralysis, Monoson, a video editor living in New York City, says she has experienced it on and off for several years now, especially during times of high stress. She recalls one episode in particular, which occurred during finals week of her senior year at New York University: “I felt like as I was falling asleep, I was also waking up,” she says. “I was in my dorm, and I knew that my roommate was in the room, but I couldn’t yell out.” Not long after her first few encounters, Monoson turned to the internet for help. Per the advice of an online sleep paralysis forum, during episodes, Monoson learned to focus on moving smaller muscles—like wiggling her toes—to break from the feeling of paralysis. Sleep paralysis affects millions every year, and studies estimate that more than half of the global population will experience at least one episode in their lifetimes. Despite the prevalence, however, the disorder is poorly understood. © 1996–2018 WGBH Educational Foundation

Keyword: Sleep
Link ID: 25671 - Posted: 11.12.2018

Tina Hesman Saey Timing is everything. Even how many calories a person burns while at rest depends on the hour. People burn about 129 more calories when resting in the afternoon and evening than in the early morning. But morning is better for burning carbohydrates, while fats are more likely to be burned in the evening, researchers report November 8 in Current Biology. The findings add to evidence that when people eat and sleep may be as important as what they eat for maintaining proper health (SN: 10/31/15, p. 10). Calories burned at rest fuel breathing, circulation and brain activity, while also helping to maintain body temperature. Researchers previously had conflicting evidence about whether a resting body burns calories at a fairly constant rate, or one that rises and falls in a daily — or circadian — rhythm. The study shows that a body’s resting metabolism is governed by circadian clocks, neuroscientist Jeanne Duffy of Brigham and Women’s Hospital in Boston and colleagues report. The study followed seven people kept in windowless rooms for three weeks, without any clues to the time of day. Each night, the seven went to bed four hours later than the previous night. That’s the equivalent of traveling around the world and crossing all time zones within a week. The schedule change allowed the researchers to study the natural body rhythms of each subject without outside influences. |© Society for Science & the Public 2000 - 2018.

Keyword: Biological Rhythms; Obesity
Link ID: 25658 - Posted: 11.09.2018

By James Gallagher Health and science correspondent, BBC News Women whose body clocks mean they are "morning people" have a lower risk of developing breast cancer, say UK researchers. The team at the University of Bristol says the reason why still needs to be uncovered. It adds the findings are important as they may affect every woman's risk. Experts said the study presented at the NCRI Cancer Conference in Glasgow added to a growing understanding of the importance of sleep in all health. Body clock Everybody has a body clock, which governs how the body works in a roughly 24-hour pattern. It's also known as a circadian rhythm. It affects everything from when we sleep, to our mood and even our risk of a heart attack. But not everybody's clock tells the same time. Morning people or "larks" are early to rise, peak earlier in the day and are tired earlier in the evening. Evening people or "owls" find it harder to get up in the morning, are productive later into the evening and prefer to go to sleep late. Take our quiz to find out whether you are a morning type, or an evening owl. And this is involved in breast cancer? The researchers think so. They used a clever new way of analysing data - called Mendelian randomisation. They looked at 341 snippets of DNA (the instructions for the human body) that control whether we are likely to be a lark or an owl. They used this knowledge to perform an experiment on more than 180,000 women in the UK Biobank project and nearly 230,000 women in the Breast Cancer Association Consortium study. They showed people genetically programmed to be "larks" were less likely to have breast cancer than those programmed to be owls. Because these bits of DNA are set at birth and are not linked to other known causes of cancer, like obesity, it means the researchers are reasonably confident body clocks are involved in cancer. © 2018 BBC

Keyword: Biological Rhythms
Link ID: 25652 - Posted: 11.07.2018

Laura Sanders SAN DIEGO — A sleepless night can leave the brain spinning with anxiety the next day. In healthy adults, overnight sleep deprivation triggered anxiety the next morning, along with altered brain activity patterns, scientists reported November 4 at the annual meeting of the Society for Neuroscience. People with anxiety disorders often have trouble sleeping. The new results uncover the reverse effect — that poor sleep can induce anxiety. The study shows that “this is a two-way interaction,” says Clifford Saper, a sleep researcher at Harvard Medical School and Beth Israel Deaconess Medical Center in Boston who wasn’t involved in the study. “The sleep loss makes the anxiety worse, which in turn makes it harder to sleep.” Sleep researchers Eti Ben Simon and Matthew Walker, both of the University of California, Berkeley, studied the anxiety levels of 18 healthy people. Following either a night of sleep or a night of staying awake, these people took anxiety tests next morning. After sleep deprivation, anxiety levels in these healthy people were 30 percent higher than when they had slept. On average, the anxiety scores reached levels seen in people with anxiety disorders, Ben Simon said November 5 in a news briefing. What’s more, sleep-deprived people’s brain activity changed. In response to emotional videos, brain areas involved in emotions were more active, and the prefrontal cortex, an area that can put the brakes on anxiety, was less active, functional MRI scans showed. The results suggest that poor sleep “is more than just a symptom” of anxiety, but in some cases, may be a cause, Ben Simon said. Citations E. Ben Simon and M.P. Walker. Underslept and overanxious: The neural correlates of sleep loss-induced anxiety in the human brain. Society for Neuroscience Annual Meeting, San Diego, November 4, 2018. |© Society for Science & the Public 2000 - 2018

Keyword: Sleep; Emotions
Link ID: 25651 - Posted: 11.07.2018

Allison Aubrey When it comes to turning back the clocks on our devices, technology has us covered. Our smartphones automatically adjust. But our internal clocks aren't as easy to re-program. And this means that the time shift to save daylight in the fall and again in the spring can influence our health in unexpected ways. "You might not think that a one hour change is a lot," says Fred Turek, who directs the Center for Sleep & Circadian Biology at Northwestern University. "But it turns out that the master clock in our brain is pretty hard-wired, " Turek explains. It's synchronized to the 24 hour light/dark cycle. Daylight is a primary cue to reset the body's clock each day. So, if daylight comes an hour earlier — as it will for many of us this weekend — it throws us off. "The internal clock has to catch up, and it takes a day or two to adjust to the new time," Turek says. Scientists have documented that the shift to daylight saving time in the spring, when we lose an hour of sleep, can increase the risk of heart attacks, strokes and traffic accidents. These studies are a reminder of just how sensitive we are to time and rhythm. Over the last 20 years, scientists have documented that, in addition to the master clock in our brains, every cell in our body has a time-keeping mechanism. These clocks help regulate important functions such as sleep and metabolism. And increasingly, there's evidence that when our habits — such as when we eat and sleep — are out of sync with our internal clocks, it can harm us. © 2018 npr

Keyword: Biological Rhythms
Link ID: 25641 - Posted: 11.03.2018

Ian Sample In daylight hours there is so little melatonin in the bloodstream that it is barely detectable. But when the sun goes down, the eyes sense the failing light, and part of the hippocampus signals the pineal gland, a pea-sized lump of tissue near the centre of the brain, to ramp up production of the sleep-promoting hormone. Levels of melatonin rise sharply from 9pm, inducing feelings of sleepiness, and remain high until the following morning. Much of the research on prescribing melatonin for children with sleep problems has focused on those with disorders such as autism, ADHD and intellectual disability (ID). For good reason too: sleeping difficulties are far more common and pronounced in children with neurodevelopmental or psychiatric disorders. For them, small doses of melatonin can be safe and effective. In one recent study, researchers from Southampton University monitored the sleep patterns of 45 children with autism, ADHD, or ID, and found that a third fell asleep faster, slept longer, and woke less frequently at night on low dose (2.5-3mg) melatonin. Above 6mg per night there was little extra benefit. A poor night’s sleep can be caused by any number of factors, but there is good evidence that screen time matters, whether it is TV, computer, tablet or mobile phone. A recent review of scientific papers on the issue found that 90% linked screen time to poor sleep in schoolchildren and adolescents. Part of the problem is obvious: being online at bedtime eats into the hours left for sleep, and it hardly helps people to wind down for the night. But glowing screens can affect sleep directly by suppressing the natural production of melatonin. Using an iPad on full brightness for two hours, for example, has been shown to suppress melatonin levels. © 2018 Guardian News and Media Limited

Keyword: Biological Rhythms; Hormones & Behavior
Link ID: 25640 - Posted: 11.03.2018

By Jason Bittel The first mammals first lived some 160 million years ago, in a world ruled by reptiles. And now scientists suggest that hiding in the dark from these terrifying beasts may have left an imprint in mammals’ genes that can still be seen today. Most mammals were no bigger than a squirrel back then, and it would have been much safer to come out only at night, thereby avoiding most of the nastiest maws and claws. A new study published Thursday in Current Biology suggests that living largely in the dark for millions of years might explain how mammals lost a light-sensitive trick that nearly every other living thing possesses. You see, if you were to examine the DNA of a turtle, an orchid, a coral, or even a bacterium, you would find a quirky little set of genes that allows these organisms to repair damage caused by one kind of sunlight with energy absorbed from another kind of sunlight. Think of it like a solar panel that is both harmed and healed by the sun. How is it possible that we lost an evolutionary strategy so advantageous it’s been found in every other living thing where scientists have looked for it? Well, you might blame the dinosaurs—or at least how scary they were. All that time spent in darkness, when most dinosaurs weren’t active, may have affected the way placental mammals evolved. Scientists call this theory the “nocturnal bottleneck,” and it’s supported by various mammalian oddities such as the shape of our eyes, the composition of our retinas, and our heightened senses of smell and hearing—all of which point to a long history of living in the dark.

Keyword: Biological Rhythms; Evolution
Link ID: 25572 - Posted: 10.15.2018

by Hannah Devlin, Science correspondent “The only known function of sleep is to cure sleepiness,” the Harvard sleep scientist Dr J Allan Hobson once joked. This isn’t quite true, but the questions of why we spend about a third of our lives asleep and what goes on in our head during this time are far from being solved. One big mystery is why sleep emerged as an evolutionary strategy. It must confer powerful benefits to balance out the substantial risks, such as being eaten or missing out on food while lying dormant. The emerging picture from research is that sleep is not a luxury but essential to both physical and mental health. But the complex and diverse functions of sleep are only just starting to be uncovered. What’s going on in our brains while we sleep? The brain doesn’t just switch off. It generates two main types of sleep: slow-wave sleep (deep sleep) – SWS – and rapid eye movement (dreaming), or REM. About 80% of our sleeping is of the SWS variety, which is characterised by slow brain waves, relaxed muscles and slow, deep breathing. There is strong evidence that deep sleep is important for the consolidation of memories, with recent experiences being transferred to long-term storage. This doesn’t happen indiscriminately though – a clearout of the less relevant experiences of the preceding day also appears to take place. A study published last year revealed that the connections between neurons, known as synapses, shrink during sleep, resulting in the weakest connections being pruned away and those experiences forgotten. © 2018 Guardian News and Media Limited

Keyword: Sleep
Link ID: 25551 - Posted: 10.09.2018

Rhitu Chatterjee Paige Thesing has struggled with insomnia since high school. "It takes me a really long time to fall asleep — about four hours," she says. For years, her mornings were groggy and involved a "lot of coffee." After a year of trying sleep medication prescribed by her doctor, she turned to the internet for alternate solutions. About four months ago, she settled on a mobile phone meditation app called INSCAPE. "It's about a 30-minute soundtrack, and it starts with a woman kind of telling you to relax and instructing your breathing," explains Thesing. "Then it goes into sounds — relaxing noises. There's wind chimes, some atmospheric music playing..." She uses the app every night and falls asleep within 15 or 20 minutes. "So, definitely a big improvement from four hours," she says. Thesing is not alone. Chronic insomnia affects an estimated 10-15 percent of adults, and another 25-35 percent struggle with sleep issues occasionally. And like Thesing, a growing number of insomniacs are turning to mobile phone apps to lull them to sleep. On Twitter and Facebook, NPR asked its audience if they have used a mobile phone app to help manage insomnia. Nearly 100 people wrote back suggesting a range of apps, including podcasts created to put a listener to sleep. "These are usually relaxation strategies, white noise, meditation," Jason Ong, an associate professor of neurology specializing in sleep at Northwestern University's Feinberg School of Medicine. He studies non-pharmacological treatments for various sleep disorders and treats patients at the university's Sleep Medicine clinic. "It's not that there's something wrong with those apps. It's a reasonable first thing to try." © 2018 npr

Keyword: Sleep
Link ID: 25540 - Posted: 10.08.2018

Since his early twenties, science writer Henry Nicholls has struggled against nearly irresistible waves of sleepiness, thanks to narcolepsy — a severe sleep disorder that science has only recently come to understand. "It's this insane weight that your fight with for a little bit and that fighting is completely worthless. There is only one outcome ever: You lose to sleep," he told CBC Radio's Quirks & Quarks. Nicholls explores the science of narcolepsy, and a whole range of other sleep disorders, in his new book Sleepyhead: The Neuroscience of a Good Night's Rest. Along the way he makes the case that the strategies used to cope with serious sleep disorders can help the rest of us sleep better, as well. Over the two decades Nicholls has lived with narcolepsy, science has learned much about it. Though it may still often go undiagnosed, it's thought to affect up to one in 2,000 people. Narcolepsy is the result of the destruction of a tiny population of neurons deep in the brain that are critical for regulating sleep. This means "it's brain damage — a tiny amount," according to Nicholls. The brain has billions of cells, but "just a few tens of thousands of cells, [are] absolutely crucial to the regulation of sleep and wakefulness," Nicholls explained. These cells produce a critical neurotransmitter called hypocretin or orexin. Hypocretin plays a role in waking up or maintaining wakefulness in many areas of the brain by releasing stimulant hormones like norepinephrine. People with narcolepsy never get this hormonal wake-up call. ©2018 CBC/Radio-Canada.

Keyword: Narcolepsy; Sleep
Link ID: 25506 - Posted: 09.29.2018

April Fulton Within three days of starting high school this year, my ninth-grader could not get into bed before 11 p.m. or wake up by 6 a.m. He complained he couldn't fall asleep but felt foggy during the school day and had to reread lessons a few times at night to finish his homework. And forget morning activities on the weekends — he was in bed. We're not the only family struggling to get restful shut-eye. "What parents are sharing with us is that the 'normal life' of a typical American high schooler is interfering with sleep," says Sarah Clark, co-director of C.S. Mott Children's Hospital National Poll on Children's Health at the University of Michigan. In the poll of 2,000 parents from various ethnic groups and backgrounds that Clark and her team published this month, 1 in 6 parents say their teen experiences frequent sleep problems — "having trouble falling asleep or staying asleep 3 or more nights per week." More than half the parents say it's because their teens won't get off their electronic devices, and 43 percent blame irregular schedules with homework and activities. A significant percentage of parents say their kids worry about school (31 percent), and 23 percent say their teens stay up worrying about their social lives. It's likely that the numbers of teens who have trouble sleeping is even higher than the poll of parents suggests, Clark says, because kids can hide their nighttime electronics use and parents may not frequently check in on older children. How can parents help? Start with knowing what kids need. © 2018 npr

Keyword: Sleep; Development of the Brain
Link ID: 25493 - Posted: 09.26.2018

Roland S. Liblau The events that lead to the sleep disorder narcolepsy are a long-standing mystery. Writing in Nature, Latorre et al.1 reveal that people with narcolepsy have unusually high levels of a type of immune cell called a T cell, which targets proteins normally present in neurons in the brain. This finding raises the question of whether narcolepsy arises because T cells unleash an autoimmune response against neurons that are important for sleep regulation. Narcolepsy affects around 1 in 2,000 people2. The symptoms usually begin in adolescence or early adulthood, and include daytime sleepiness and, in some cases, cataplexy — sudden muscle weakness during wakefulness that causes falls. A small population of neurons in the brain produces a protein called hypocretin, which controls sleep–wake cycles3, and narcolepsy-like symptoms occur in animals that have defects in genes required for the production of or response to hypocretin4. Narcolepsy type 2 is associated with daytime sleepiness, and this can progress to narcolepsy type 1, which is characterized by sleepiness and cataplexy. People with narcolepsy type 1 have abnormally low numbers of hypocretin-producing neurons5. Hypocretin levels in the cerebrospinal fluid that bathes the brain and spinal cord can be measured to help diagnose6 narcolepsy type 1, and such tests provide a way of indirectly monitoring the loss of hypocretin-producing neurons over time. The trajectory of this neuronal loss remains to be fully understood, but can take months or years. © 2018 Springer Nature Limited.

Keyword: Narcolepsy; Neuroimmunology
Link ID: 25485 - Posted: 09.24.2018