Links for Keyword: Sleep

Follow us on Facebook and Twitter, or subscribe to our mailing list, to receive news updates. Learn more.


Links 1 - 20 of 689

By DONALD G. MCNEIL Where was I? Sorry — must have nodded off for a decade. Ten years ago, I spent two nights in a sleep lab at SUNY Downstate Medical Center, taking the test for sleep apnea, and wrote about it for Science Times. Back then, “sleep technicians” wired me up like the Bride of Frankenstein: 15 sensors glued or clamped to my scalp, lip, eye sockets, jaw, index finger, chest and legs, two belts around my torso, and a “snore mike” on my neck. As I slept, an infrared camera watched over me. And I ended up spending 23 hours in that hospital bed because the test wasn’t over until you could lie in a dark room for 20 minutes without dozing off. I had such a sleep deficit that I kept conking out, not just all night, but all the next day. So this year, when a company called NovaSom offered to let me try out a new home sleep-test kit that promises to streamline the process, I said yes. In the decade since my ordeal, the pendulum has swung sharply in the direction of the home test, said Dr. M. Safwan Badr, past president of the American Academy of Sleep Medicine, which first recognized home testing for apnea in 2007. Insurers prefer it because it costs only about $300, about one-tenth that of a hospital test, and many patients like it, too. “Lots of people are reluctant to let a stranger watch them sleep,” said Dr. Michael Coppola, a former president of the American Sleep Apnea Association who is now the chief medical officer at NovaSom. Doctors estimate that 18 million Americans have moderate to severe apnea and 75 percent of them do not know it. Home testing is not recommended for those with heart failure, emphysema, seizures and a few other conditions. And because it does not record brain waves as a hospital lab does, a home test can be fooled by someone who just lies awake all night staring at the ceiling. But it’s useful for many people who exhibit the warning signs of apnea, such as waking up exhausted after a full night’s sleep or dozing off at the wheel in bright daylight. And severe apnea can be lethal: starving the brain of oxygen all night quadruples the risk of stroke. © 2014 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: 19865 - Posted: 07.22.2014

Carmen Fishwick Do you have difficulty getting enough sleep? Sleep problems affect one in three of us at any one time, and about 10% of the population on a chronic basis. Of Guardian readers who responded to a recent poll, 23% reported that they sleep between four and six hours a night. With continued lack of sufficient sleep, the part of the brain that controls language and memory is severely impaired, and 17 hours of sustained wakefulness is equivalent to performing on a blood alcohol level of 0.05% – the UK's legal drink driving limit. In 2002, American researchers analysed data from more than one million people, and found that getting less than six hours' sleep a night was associated with an early demise – as was getting over eight hours. Studies have found that blood pressure is more than three times greater among those who sleep for less than six hours a night, and women who have less than four hours of sleep are twice as likely to die from heart disease. Other research suggests that a lack of sleep is also related to the onset of diabetes, obesity, and cancer. Are you worried about how much sleep you get? Professor Russell Foster, chair of circadian neuroscience and head of the Sleep and Circadian Neuroscience Institute at the University of Oxford, and professor Colin Espie, professor of sleep medicine at the University of Oxford and lead researcher on the Great British Sleep Survey, answered reader questions. © 2014 Guardian News and Media Limited

Related chapters from BP7e: Chapter 14: Biological Rhythms, Sleep, and Dreaming
Related chapters from MM:Chapter 10: Biological Rhythms and Sleep
Link ID: 19724 - Posted: 06.14.2014

by Moheb Costandi Rest easy after learning a new skill. Experiments in mice suggest that a good night's sleep helps us lay down memories by promoting the growth of new connections between brain cells. Neuroscientists believe that memory involves the modification of synapses, which connect brain cells, and numerous studies published over the past decade have shown that sleep enhances the consolidation of newly formed memories in people. But exactly how these observations were related was unclear. To find out, Wenbiao Gan of the Skirball Institute of Biomolecular Medicine at New York University Medical School and his colleagues trained 15 mice to run backwards or forwards on a rotating rod. They allowed some of them to fall asleep afterwards for 7 hours, while the rest were kept awake. The team monitored the activity and microscopic structure of the mice's motor cortex, the part of the brain that controls movement, through a small transparent "window" in their skulls. This allowed them to watch in real time how the brain responded to learning the different tasks. Sprouting spines They found that learning a new task led to the formation of new dendritic spines – tiny structures that project from the end of nerve cells and help pass electric signals from one neuron to another – but only in the mice left to sleep. This happened during the non-rapid eye movement stage of sleep. Each task caused a different pattern of spines to sprout along the branches of the same motor cortex neurons. © 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: 19705 - Posted: 06.06.2014

Damage to certain parts of the brain can lead to a bizarre syndrome called hemispatial neglect, in which one loses awareness of one side of their body and the space around it. In extreme cases, a patient with hemispatial neglect might eat food from only one side of their plate, dress on only one side of their body, or shave or apply make-up to half of their face, apparently because they cannot pay attention to anything on that the other side. Research published last week now suggests that something like this happens to all of us when we drift off to sleep each night. The work could help researchers to understand the causes of hemispatial neglect, and why it affects one side far more often than the other. It also begins to reveal the profound changes in conscious experience that take place while we fall asleep, and the brain changes that accompany them. Hemispatial neglect is a debilitating condition that occurs often in people who suffer a stroke, where damage to the left hemisphere of the brain results in neglect of the right half of space, and vice versa. It can occur as a result of damage to certain parts of the frontal lobes, which are involved in alertness and attention, and the parietal lobes, which process information about the body and its surrounding space. In clinical tests, patients with hemispatial neglect are typically unaware of all kinds of stimuli in one half of space – they fail to acknowledge objects placed in the affected half of their visual field, for example and cannot state the location of touch sensations on the affected side of their body. Some may stop using the limbs on the affected side, or even deny that the limbs belong to them. Patients with neglect can usually see perfectly well, but information from the affected side just does not reach their conscious awareness. © 2014 Guardian News and Media Limited

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: Language and Our Divided Brain
Link ID: 19682 - Posted: 06.03.2014

By Brady Dennis The Food and Drug Administration is worried that a sleeping pill you take tonight could make for a riskier drive to work tomorrow. In its latest effort to make sure that the millions of Americans taking sleep medications don’t drowsily endanger themselves or others, the agency on Thursday said it will require the manufacturer of the popular drug Lunesta to lower the recommended starting dose, after data showed that people might not be alert enough to drive the morning after taking the drug, even if they feel totally awake. The current recommended starting dose of eszopiclone, the drug marketed as Lunesta, is 2 milligrams at bedtime for both men and women. The FDA said that initial dose should be cut in half to 1 milligram, though it could be increased if needed. People currently taking 2 and 3 milligram doses should ask a doctor about how to safely continue taking the medication, as higher doses are more likely to impair driving and other activities that require alertness the following morning, the agency said. “To help ensure patient safety, health care professionals should prescribe, and patients should take, the lowest dose of a sleep medicine that effectively treats their insomnia,” Ellis Unger, of FDA’s Center for Drug Evaluation and Research, said in a statement. In 2013, the FDA said, approximately 3 million prescriptions of Lunesta were dispensed to nearly a million patients in the United States. Lunesta, made by Sunovion Pharmaceuticals, also recently became available in generic form. The new rules, including changes to existing labels, will apply both to the brand-name and generic forms of the drug. FDA officials said the decision came, in part, after seeing findings from a study of 91 healthy adults between the ages 25 and 40. Compared to patients on a placebo, those taking a 3 milligram dose of Lunesta were associated with “severe next-morning psychomotor and memory impairment in both men and women,” the agency said. The study found that even people taking the recommended dose could suffer from impaired driving skills, memory and coordination as long as 11 hours after taking the drug. Even scarier: The patients often claimed that they felt completely alert, with no hint of drowsiness. © 1996-2014 The Washington Post

Related chapters from BP7e: Chapter 14: Biological Rhythms, Sleep, and Dreaming
Related chapters from MM:Chapter 10: Biological Rhythms and Sleep
Link ID: 19622 - Posted: 05.15.2014

by Helen Thomson If you liked Inception, you're going to love this. People have been given the ability to control their dreams after a quick zap to their head while they sleep. Lucid dreaming is an intriguing state of sleep in which a person becomes aware that they are dreaming. As a result, they gain some element of control over what happens in their dream – for example, the dreamer could make a threatening character disappear or decide to fly to an exotic location. Researchers are interested in lucid dreaming because it can help probe what happens when we switch between conscious states, going from little to full awareness. In 2010, Ursula Voss at the J.W. Goethe University in Frankfurt, Germany, and her colleagues trained volunteers to move their eyes in a specific pattern during a lucid dream. By scanning their brains while they slept, Voss was able to show that lucid dreams coincided with elevated gamma brainwaves. This kind of brainwave occurs when groups of neurons synchronise their activity, firing together about 40 times a second. The gamma waves occurred mainly in areas situated towards the front of the brain, called the frontal and temporal lobes. Perchance to dream The team wanted to see whether gamma brainwaves caused the lucid dreams, or whether both were side effects of some other change. So Voss and her colleagues began another study in which they stimulated the brain of 27 sleeping volunteers, using a non-invasive technique called transcranial alternating current. © Copyright Reed Business Information Ltd.

Related chapters from BP7e: Chapter 14: Biological Rhythms, Sleep, and Dreaming; Chapter 18: Attention and Higher Cognition
Related chapters from MM:Chapter 10: Biological Rhythms and Sleep; Chapter 14: Attention and Consciousness
Link ID: 19603 - Posted: 05.12.2014

One of our most mysterious and intriguing states of consciousness is the dream. We lose consciousness when we enter the deep waters of sleep, only to regain it as we emerge into a series of uncanny private realities. These air pockets of inner experience have been difficult for psychologists to study scientifically and, as a result, researchers have mostly resorted to measuring brain activity as the sleeper lies passive. But interest has recently returned to a technique that allows real-time communication from within the dream world. The rabbit hole between these worlds of consciousness turns out to be the lucid dream, where people become aware that they are dreaming and can influence what happens within their self-generated world. Studies suggest that the majority of people have had a lucid dream at some point in their life but that the experience is not common. As a result, there is now a minor industry in technologies and training techniques that claim to increase your chance of having a lucid dream although a recent scientific review estimated that the effect of any particular strategy is moderate at best. Some people, however, can reliably induce lucid dreams and it's these people who are allowing us to conduct experiments inside dreams. When trying to study an experience or behaviour, cognitive scientists usually combine subjective reports, what people describe about their experience, with behavioural experiments, to see what effect a particular state has on how people reason, act or remember. But both are difficult in dreamers, because they can't tell you much until they wake up and active participation in experiments is difficult when you are separated from the world by a blanket of sleep-induced paralysis. This paralysis is caused by neurons in the brainstem that block signals from the action-generating areas in the brain to the spinal nerves and muscles. The shutdown happens when Rapid Eye Movement or REM sleep starts, meaning that dreaming of even the most energetic actions results in no more than a slight twitch. One of the few actions that are not paralysed, however, is eye movement. This is where REM sleep gets its name from and this window of free action provides the lucid dreamer a way of signalling to the outside world. © 2014 Guardian News and Media Limited

Related chapters from BP7e: Chapter 14: Biological Rhythms, Sleep, and Dreaming
Related chapters from MM:Chapter 10: Biological Rhythms and Sleep
Link ID: 19543 - Posted: 04.28.2014

By Dwayne Godwin and Jorge Cham ABOUT THE AUTHOR(S) Dwayne Godwin is a neuroscientist at the Wake Forest University School of Medicine. Jorge Cham draws the comic strip Piled Higher and Deeper at www.phdcomics.com. © 2014 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: 19473 - Posted: 04.12.2014

By JoNel Aleccia The engineer who drove a speeding commuter train off the rails in New York last year may have suffered from the most severe form of a dangerous sleep disorder, but health experts say he has plenty of company. As many as 22 million people in the U.S. — or up to 7 percent of the population — may suffer from obstructive sleep apnea, experts say. It’s a condition that causes airways to collapse during sleep, cutting off breathing dozens or sometimes hundreds of times a night, leaving them bleary-eyed and drowsy, even after a full night’s rest. William Rockefeller, 46, was diagnosed after the December 2013 crash that killed four and injured more than 70 with severe obstructive sleep apnea, documents released this week show. On a scale where as few as five sleep disruptions an hour can make someone sleepy, and 30 episodes are considered severe, Rockefeller logged about 66 arousals an hour, doctors said. “His sleep was really fragmented,” said Dr. Phyllis Zee, a sleep expert with the Northwestern Medicine Sleep and Circadian Rhythms Research Program. “Even if he were to sleep seven or eight hours, he would be sleep-deprived.” Zee and her colleagues suspected that Rockefeller might suffer from sleep deprivation. He was obese, records show, and there’s a certain fatigued look that she saw in news photos of the engineer. “That was one of my thoughts, ‘Oh my goodness, he has (OSA),’” she said.

Related chapters from BP7e: Chapter 14: Biological Rhythms, Sleep, and Dreaming
Related chapters from MM:Chapter 10: Biological Rhythms and Sleep
Link ID: 19457 - Posted: 04.08.2014

By Helen Briggs BBC News Sleep loss may be more serious than previously thought, causing a permanent loss of brain cells, research suggests. In mice, prolonged lack of sleep led to 25% of certain brain cells dying, according to a study in The Journal of Neuroscience. If the same is true in humans, it may be futile to try to catch up on missed sleep, say US scientists. They think it may one day be possible to develop a drug to protect the brain from the side-effects of lost sleep. The study, published in The Journal of Neuroscience, looked at lab mice that were kept awake to replicate the kind of sleep loss common in modern life, through night shifts or long hours in the office. A team at the University of Pennsylvania School of Medicine studied certain brain cells which are involved in keeping the brain alert. After several days of sleep patterns similar to those followed by night workers - three days of night shifts with only four to five hours sleep in 24 hours - the mice lost 25% of the brain cells, known as locus coeruleus (LC) neurons. The researchers say this is the first evidence that sleep loss can lead to a loss of brain cells. But they add that more work needs to be done to find out if people who miss out on sleep might also be at risk of permanent damage. Prof Sigrid Veasey of the Center for Sleep and Circadian Neurobiology, told BBC News: "We now have evidence that sleep loss can lead to irreversible injury. "This might be in a simple animal but this suggests to us that we are going to have to look very carefully in humans." BBC © 2014

Related chapters from BP7e: Chapter 14: Biological Rhythms, Sleep, and Dreaming
Related chapters from MM:Chapter 10: Biological Rhythms and Sleep
Link ID: 19382 - Posted: 03.19.2014

By Christina Ianzito, We get it: Sleep is good for us. The National Sleep Foundation regularly campaigns “to celebrate the health benefits of sleep,” and experts have been boosting sleep’s values as no less important than proper diet and exercise. Insufficient sleep has been linked to stroke, obesity and heart disease. But sleeping too much may also be risky: It, too, is associated with a higher risk of heart disease and obesity, not to mention diabetes and depression. So, how much is too much? And if you’re sleep-deprived during the week, does sleeping 10 or 11 hours on Saturday and Sunday to catch up put you in any jeopardy? Most experts say that a healthy amount of sleep for an adult is a regular seven to nine hours a night. And the operative term here is “regular,” meaning the issue isn’t the college kid who power-sleeps 15 hours on vacation to catch up from too much studying (or partying). When scientists refer to “long sleepers,” they’re referring to people who consistently sleep nine or more hours a night, says Kristen Knutson, a biomedical anthropologist who focuses on sleep research at the University of Chicago’s Department of Medicine. “If you’ve been pulling all-nighters, by all means extend your sleep on the weekend if you can; try to catch up,” Knutson says, “but if you’re sleeping nine or 10 hours night after night after night for months on end . . . then we’ve got to understand why are you sleeping so much.” You might be getting poor-quality sleep, she adds, or are “already on the pathway to illness and your body is reacting by wanting you to sleep more.” © 1996-2014 The Washington Post

Related chapters from BP7e: Chapter 14: Biological Rhythms, Sleep, and Dreaming
Related chapters from MM:Chapter 10: Biological Rhythms and Sleep
Link ID: 19369 - Posted: 03.17.2014

Linda Carroll TODAY contributor Insomnia isn’t something that just happens at night. Researchers have now shown that insomniacs have more active brains than sound sleepers, according to a report published Friday in the journal Sleep. That means sleeplessness may, in fact, have its roots in brain wiring that affects the way our minds work, no matter what time of day it is. “We see insomnia now as more of a 24/7 disorder,” said Dr. Rachel Salas, an assistant professor of neurology at the Johns Hopkins University School of Medicine and lead author of the new study. “It’s like a light switch is continually on. So their brains are always running.” Salas originally thought that sound sleepers would be the ones with more alert and plastic brains. (Brain plasticity basically means how neural pathways can be modified by experience or that it is able to adapt or grow.) To prove the theory, Salas set up an experiment that compared 18 chronic insomniacs to 10 sound sleepers. All of the study volunteers were hooked up to a device that sends magnetic waves through the skull and into the brain. Because transcranial magnetic stimulation (TMS) can be aimed a specific site, the researchers were able to target a point in the motor cortex that controls movements of the thumb. Each magnetic pulse sparked an involuntary twitching of the digit. After 65 run-throughs with the TMS, study volunteers were asked to practice moving their thumbs on their own in a manner opposite to the one that was sparked by the TMS. So, for example, if the TMS sent volunteers’ thumbs flicking up and left, they would be asked to wiggle their digits down and right.

Related chapters from BP7e: Chapter 14: Biological Rhythms, Sleep, and Dreaming
Related chapters from MM:Chapter 10: Biological Rhythms and Sleep
Link ID: 19305 - Posted: 03.01.2014

By Meeri Kim, How often, and how well, do you remember your dreams? Some people seem to be super-dreamers, able to recall effortlessly their dreams in vivid detail almost every day. Others struggle to remember even a vague fragment or two. A new study has discovered that heightened blood flow activity within certain regions of the brain could help explain the great dreamer divide. In general, dream recall is thought to require some amount of wakefulness during the night for the vision to be encoded in longer-term memory. But it is not known what causes some people to wake up more than others. A team of French researchers looked at brain activation maps of sleeping subjects and homed in on areas that could be responsible for nighttime wakefulness. When comparing two groups of dreamers on the opposite ends of the recall spectrum, the maps revealed that the temporoparietal junction — an area responsible for collecting and processing information from the external world — was more highly activated in high-recallers. The researchers speculate that this allows these people to sense environmental noises in the night and wake up momentarily — and, in the process, store dream memories for later recall. In support of this hypothesis, previous medical cases have found that when these same portions of the brain are damaged by stroke, patients lose the ability to remember their dreams, even though they can still achieve the REM (rapid eye movement) stage of sleep in which dreaming usually occurs. © 1996-2014 The Washington Post

Related chapters from BP7e: Chapter 14: Biological Rhythms, Sleep, and Dreaming; Chapter 2: Functional Neuroanatomy: The Nervous System and Behavior
Related chapters from MM:Chapter 10: Biological Rhythms and Sleep; Chapter 2: Cells and Structures: The Anatomy of the Nervous System
Link ID: 19286 - Posted: 02.24.2014

By ANAHAD O'CONNOR Many people occasionally wake up in the middle of the night and find themselves unable to get back to sleep. But if it happens often, and you are consistently tired and not functioning well during the day, that is indicative of a problem, said Dr. Meir H. Kryger, a professor at Yale School of Medicine and the author of “The iGuide to Sleep.” Stressful events, a loud pet or a snoring bedmate may be to blame, or the problem could be a medical issue such as a cough, sleep apnea or getting up to urinate — which could be a sign of diabetes. Dr. Kryger said he has had patients who are stirred awake by the sensation of their heart beating rapidly because of a cardiac rhythm problem. Worrying about being awake only makes the problem worse. “We see that in patients who’ve had insomnia for a while,” Dr. Kryger said. “They wake up and become so angry, frustrated and aroused that they can’t fall asleep.” In some cases better habits can help. Nicotine or alcohol levels fall during sleep and can cause people to awaken, so quitting smoking or avoiding alcoholic beverages, especially before bedtime, can help. Steer clear of heavy or spicy meals before trying to sleep if heartburn or acid reflux is keeping you up. You may be tempted to nap during the day to compensate for lost sleep time, but this can just prolong the problem, Dr. Kryger said. Avoid taking naps that are longer than 20 minutes, particularly in the evening. If you wake up at night and find that you still cannot get back to asleep after 20 minutes, do not lie there in anguish staring at your clock. Get out of bed and do something that distracts and relaxes you, like reading a book. Then return to bed when you feel sleepy. © 2014 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: 19276 - Posted: 02.22.2014

By Caitlin Kirkwood Glorious, refreshing sleep is eluding the majority of Americans. According to the National Sleep Foundation’s 2013 International Bedroom Poll 56 percent of people between the ages of 25 and 55 get an insufficient amount of sleep on workdays. On non-workdays individuals are then more likely to oversleep. They spend an additional 45 minutes catching Z’s in an attempt to compensate for accrued workweek sleep debt. Why are we constantly playing sleep-catch up during free time? As a society we are socially jet lagged. Social jet lag is the difference betweensleep patterns on work days and free days. These inconsistent sleeping habits result in sleep loss that is reminiscent of flying west across several time zones every Friday evening and traveling back East come Monday morning. The pattern reveals a critical disparity between society-imposed obligations, like work and family commitments, and our innate biological clock. Social jet lag might not sound like a big deal. What’s an hour or two of sleep lost here and there? But the chronic misalignment between our social and biological clocks is wreaking havoc on our health. Large-scale epidemiological studies have pointed a finger at short sleep duration for it’s causative role in the nationwide obesity crisis. When you get too little sleep, normal levels of appetite hormones are altered in a way that could lead to increased food consumption and weight gain. Unfortunately for people struggling with social jet lag, short sleep duration comes with the territory of the workweek. Some data even suggest that for every hour the biological clock is offset from the social clock, the chances of being overweight shoot-up by a whopping 33 percent. And supersizing the body mass index isn’t the only problem. Social jet lag has also been linked to the increased likelihood of nicotine and alcohol use, which independently contribute to additional health problems. © 2014 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: 19240 - Posted: 02.12.2014

Posted by Maria Konnikova On a typical workday morning, if you’re like most people, you don’t wake up naturally. Instead, the ring of an alarm clock probably jerks you out of sleep. Depending on when you went to bed, what day of the week it is, and how deeply you were sleeping, you may not understand where you are, or why there’s an infernal chiming sound. Then you throw out your arm and hit the snooze button, silencing the noise for at least a few moments. Just another couple of minutes, you think. Then maybe a few minutes more. It may seem like you’re giving yourself a few extra minutes to collect your thoughts. But what you’re actually doing is making the wake-up process more difficult and drawn out. If you manage to drift off again, you are likely plunging your brain back into the beginning of the sleep cycle, which is the worst point to be woken up—and the harder we feel it is for us to wake up, the worse we think we’ve slept. (Ian Parker wrote about the development of a new drug for insomnia in the magazine last week.) One of the consequences of waking up suddenly, and too early, is a phenomenon called sleep inertia. First given a name in 1976, sleep inertia refers to that period between waking and being fully awake when you feel groggy. The more abruptly you are awakened, the more severe the sleep inertia. While we may feel that we wake up quickly enough, transitioning easily between sleep mode and awake mode, the process is in reality far more gradual. Our brain-stem arousal systems (the parts of the brain responsible for basic physiological functioning) are activated almost instantly. But our cortical regions, especially the prefrontal cortex (the part of the brain involved in decision-making and self-control), take longer to come on board. © 2013 Condé Nast.

Related chapters from BP7e: Chapter 14: Biological Rhythms, Sleep, and Dreaming
Related chapters from MM:Chapter 10: Biological Rhythms and Sleep
Link ID: 19211 - Posted: 02.06.2014

|By Roni Jacobson There is nothing like a good night's sleep to help you feel your best the next day. Now scientists are finding that good sleep habits may do more than restore cognitive function on a nightly basis—they may also fortify the brain over the long term, according to a new study in the Journal of Neuroscience. Researchers at the University of Wisconsin–Madison found that during sleep, activity ramps up in genes that are involved in producing oligodendrocytes—brain cells responsible for coating neurons with myelin. Myelin is the brain's insulating material. The fatty substance surrounds the signal-transmitting tail that extends from every neuron, enabling electrical communications to travel quickly and efficiently to other neurons. Myelin deficiency is at the root of the neurodegenerative disease multiple sclerosis and can contribute to symptoms such as fatigue, vision and hearing impairment, and a loss of coordination. In this study, sleeping mice had heightened activity in the genes responsible for creating oligodendrocytes, but awake or sleep-deprived rodents showed greater activity in genes involved in cellular stress and death. Chiara Cirelli, a neuroscientist and author on the paper, suggests that sleep helps cells regenerate and repair themselves, by enabling the body to produce new myelin after it has deteriorated. Cellular repair probably takes weeks or even months, however, so pulling an occasional all-nighter is unlikely to disrupt the process. © 2014 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: 19185 - Posted: 01.30.2014

By MARIA KONNIKOVA SLEEP seems like a perfectly fine waste of time. Why would our bodies evolve to spend close to one-third of our lives completely out of it, when we could instead be doing something useful or exciting? Something that would, as an added bonus, be less likely to get us killed back when we were sleeping on the savanna? “Sleep is such a dangerous thing to do, when you’re out in the wild,” Maiken Nedergaard, a Danish biologist who has been leading research into sleep function at the University of Rochester’s medical school, told me. “It has to have a basic evolutional function. Otherwise it would have been eliminated.” We’ve known for some time that sleep is essential for forming and consolidating memories and that it plays a central role in the formation of new neuronal connections and the pruning of old ones. But that hardly seems enough to risk death-by-leopard-in-the-night. “If sleep was just to remember what you did yesterday, that wouldn’t be important enough,” Dr. Nedergaard explains. In a series of new studies, published this fall in the journal Science, the Nedergaard lab may at last be shedding light on just what it is that would be important enough. Sleep, it turns out, may play a crucial role in our brain’s physiological maintenance. As your body sleeps, your brain is quite actively playing the part of mental janitor: It’s clearing out all of the junk that has accumulated as a result of your daily thinking. Recall what happens to your body during exercise. You start off full of energy, but soon enough your breathing turns uneven, your muscles tire, and your stamina runs its course. What’s happening internally is that your body isn’t able to deliver oxygen quickly enough to each muscle that needs it and instead creates needed energy anaerobically. And while that process allows you to keep on going, a side effect is the accumulation of toxic byproducts in your muscle cells. Those byproducts are cleared out by the body’s lymphatic system, allowing you to resume normal function without any permanent damage. © 2014 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: 19123 - Posted: 01.13.2014

By CATHERINE SAINT LOUIS The standard treatment for people with moderate to severe obstructive sleep apnea is a mask worn at night that helps them breathe without interruption. The mask is unwieldy and uncomfortable, however; one study found that46 percent to 83 percent of patients with obstructive sleep apnea do not wear it diligently. Now scientists may have found an alternative, at least for some patients: a pacemaker-like device implanted in the chest that stimulates a nerve in the jaw, helping to keep part of the upper airway open. The device, called a neurostimulator, helped reduce breathing interruptions and raise blood oxygen levels in about two-thirds of sleep apnea patients participating in a trial, researchers reported on Wednesday in The New England Journal of Medicine. “This is a new paradigm of surgical treatment that seems to effectively control obstructive sleep apnea in selected patients,” said Dr. Sean M. Caples, a sleep specialist in the division of pulmonary and critical care medicine at Mayo Clinic in Rochester, Minn. “It’s very exciting.” Still, Dr. Caples, who was not involved in the new study, noted that “a third of patients were not improved when all was said and done,” even though they were chosen because they were seen as likely to benefit. The new trial was funded by the maker of the device, Inspire Medical Systems. At 22 sites internationally, in 126 patients, doctors surgically implanted a remote-controlled neurostimulator that, activated at night, sends regular electric impulses to a nerve inside the jaw. The impulses cause the tongue to move forward during inhalation, opening the airway. Copyright 2014 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: 19120 - Posted: 01.11.2014

The maker of a type of sleeping pill is lowering the dose to minimize the risk of next-day drowsiness. The drug, Sublinox, has been associated in the past with abnormal sleep behaviours. In late 2011, Meda Valeant Pharma Canada warned that some people taking the drug had reported getting out of bed while not fully awake and performing activities they were unaware of doing. Those activities including driving a car, eating and making phone calls The drug company has lowered the recommended initial dose to five milligrams for women and either five or 10 milligrams for men. The drug company says Sublinox should be taken immediately before bedtime, when the user will have the opportunity to get at least seven or eight hours of sleep. People aged 65 and older should use the five-milligram dose, regardless of gender, the company says. Meda Valeant Pharma Canada issued the new advice in conjunction with Health Canada. Long-term use not recommended The advisory says women metabolize the drug more slowly than men, and therefore have a higher chance of experiencing next-day drowsiness. Sublinox — the brand name for the drug zolpidem — is a hypnotic. As with all drugs of this class, long-term use is not recommended. It should not be taken in the middle of the night or at any time other than bedtime, the statement says. © CBC 2014

Related chapters from BP7e: Chapter 14: Biological Rhythms, Sleep, and Dreaming; Chapter 18: Attention and Higher Cognition
Related chapters from MM:Chapter 10: Biological Rhythms and Sleep; Chapter 14: Attention and Consciousness
Link ID: 19094 - Posted: 01.04.2014