Chapter 10. Biological Rhythms and Sleep

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By Lisa Sanders, M.D. “I know what Danny has,” said the boy’s aunt to the boy’s mother, her sister-in-law. Her voice on the phone cracked with excitement. “I saw someone just like him on TV!” This was last fall, and Danny was 18. He had been a medical mystery since he was 7 months old. His mother recalled that she had just finished changing his diaper and picked him up when she heard him make a strange clicking noise, his mouth opening and closing oddly. And then his head flopped back as she held him. She hurried to the living room of their Queens home to show her husband, but by the time she got there, Danny was fine. Those sudden episodes of clicking and collapse happened again and again, eventually occurring more than 100 times a day. His first doctors thought these episodes could be tiny seizures. But none of the antiseizure medications they prescribed helped. Then, when Danny was 8, and almost too big for his mother to catch when he slow-motion slumped to the floor, his parents found a doctor who was willing to explore a different diagnosis and treatment. Could this be a rare disease known as cataplexy? In this disorder, patients have episodes of sudden weakness in the skeletal muscles of the body. In some, cataplexy may affect only the face or neck, causing the eyelids to droop or the head to fall forward. But in others, it can also affect the entire body. These episodes are often triggered by strong emotion, which was the case for Danny. Cataplexy is usually part of another rare disorder, narcolepsy, in which the normal control of sleep and wakefulness is somehow lost. Those with narcolepsy have sudden episodes of sleep that invade their waking hours and transient periods of wakefulness that disrupt their sleep. © 2020 The New York Times Company

Keyword: Sleep; Epilepsy
Link ID: 27290 - Posted: 06.08.2020

Allison Aubrey Sleep makes everything easier, even in these difficult days. Why then is it so hard to get? For most of us, right now, it takes work to settle our minds so we can rest. From medication to melatonin to putting on fuzzy socks, we all have routines we hope will help us drift off into sleep. And for good reason. "You've just got to gradually bring the brain and the body down, sort of from that altitude of wakefulness onto the hard, safe landing pad of sleep at night," says Matthew Walker, a sleep researcher at the University of California, Berkeley and the author of Why We Sleep. Don't count sheep Not only will counting sheep not help you fall asleep faster, but a study by Allison Harvey at UC Berkeley found that it actually "made it harder to fall asleep, and it took you longer to fall asleep." Do use calming mental imagery Harvey found that other types of mental imagery, however, are conducive to sleep. Walker suggests imagining a pleasant walk you've taken before, "like a hike in the woods or if it's a walk down on a beach that you do on vacation." Mentally navigating that walk, he says, "tended to hasten the speed of the onset of sleep." Try relaxation and meditation apps as training wheels "I'm a big fan of those things," says Chris Winter, a neurologist and sleep researcher in Charlottesville, Virginia. These apps can train you to meditate — to clear away regrets about the past and worries about the future so you can learn to be in the moment. "The ability to settle your mind and initiate sleep is a skill," Winter says. "The more you practice it, the better you'll get at it and the more confident you become." Melatonin has mixed results © 2020 npr

Keyword: Sleep; Stress
Link ID: 27289 - Posted: 06.08.2020

Veronique Greenwood Inside a series of tubes in a bright, warm room at Harvard Medical School, hundreds of fruit flies are staying up late. It has been days since any of them have slept: The constant vibrations that shake their homes preclude rest, cling as they might to the caps of the tubes for respite. Not too far away in their own tubes live other sleepless flies, animated with the calm persistence of those consigned to eternal day. A genetic tweak to certain neurons in their brains keeps them awake for as long as they live. They do not live long. The shaken flies and the engineered flies both die swiftly — in fact, the engineered ones survive only half as long as well-rested controls. After days of sleeplessness, the flies’ numbers tumble, then crash. The tubes empty out. The lights shine on. We all know that we need sleep to be at our best. But profound sleep loss has more serious and immediate effects: Animals completely deprived of sleep die. Yet scientists have found it oddly hard to say exactly why sleep loss is lethal. Sleep is primarily seen as a neurological phenomenon, and yet when deprived creatures die, they have a puzzlingly diverse set of failures in the body outside the nervous system. Insufficient sleep in humans and lab animals, if chronic, sets up health problems that surface over time, such as heart disease, high blood pressure, obesity and diabetes. But those conditions are not what slays creatures that are 100% sleep deprived within days or weeks. What does sleep do that makes it deadly to go without? Could answering that question explain why we need sleep in the first place? Under the pale light of the incubators in Dragana Rogulja’s lab at Harvard Medical School, sleepless flies have been living and dying as she pursues the answers. Simons Foundation © 2020

Keyword: Sleep; Neuroimmunology
Link ID: 27285 - Posted: 06.06.2020

Patti Neighmond Having trouble getting to sleep these days? You're not alone. For people with a history of insomnia, sleep problems are magnified right now. And many who never struggled before are suddenly experiencing interruptions in their nightly rest or difficulty falling asleep. It's pretty typical that in moments of anxiety, sleep suffers, but the situation we're all living through today means the anxiety never stops, says neurologist and sleep specialist Dr. Douglas Kirsch, past president of the American Academy of Sleep Medicine. For occasional insomnia, the problems go away when the specific trigger is resolved. But now, he says, there's no resolution or relief from "the constant inflow of anxiety-provoking news." And that spells trouble for sleep. Family doctors and sleep specialists say many people who are feeling grief, frustration and anxiety, whether about the pandemic, financial worries or racial inequalities and unrest in the U.S., are finding themselves unable to sleep. And it's not just the worry. It's the interrupted schedules and isolation of the pandemic too. Here's why it's not all in your head and what they say you can do about it. We're suffering "collective social anxiety" — tame it to sleep better Before the pandemic, Arlene Rentas, a busy currency trader in Charlotte, N.C., kept a regular schedule and slept like clockwork. She would awaken at 5:30 in the morning and be out the door by 7 a.m., home by 8 p.m. and, after a quick run, in bed around 10 p.m. © 2020 npr

Keyword: Sleep; Stress
Link ID: 27276 - Posted: 06.03.2020

By Christina Caron For the Langstaff family, the bedtime routine had become more like a bedtime marathon. “My son has struggled with sleep from the moment he was born,” Anna Langstaff, the head of a Montessori school in Portland, Ore., said of her 6-year-old son, Henry. “We used to joke that he was like a little knight fighting a dragon called sleep.” When Henry was a toddler, dimming the lights and other bedtime cues simply sent him into “battle mode” she said. “He’d start yelling, ‘No bed! No bed!’” After years of struggling with what had become a two-hour bedtime routine, the Langstaffs turned to their pediatrician, who recommended a chocolate containing melatonin, a hormone secreted by a pea-size organ in the brain called the pineal gland that helps regulate the body’s internal clock and induces sleepiness. “It was like magic,” she said. Now Henry falls asleep at 7:30 p.m. and continues to wake up at the same time he always has, shortly before 6 a.m., Langstaff said. “Magic” — “game changer” — these are words frequently used by parents describing how melatonin helps their children fall asleep. An online survey of 933 parents with children under 18 conducted by YouGov for The New York Times in May found that only about a third had kids who were struggling with sleep issues in the past year. But among those parents, almost half had given melatonin to their children. © 2020 The New York Times Company

Keyword: Sleep; Hormones & Behavior
Link ID: 27253 - Posted: 05.18.2020

Diana Kwon As Earth rotates around its axis, the organisms that inhabit its surface are exposed to daily cycles of darkness and light. In animals, light has a powerful influence on sleep, hormone release, and metabolism. Work by Takaomi Sakai, a neuroscientist at Tokyo Metropolitan University, and his team suggests that light may also be crucial for forming and maintaining long-term memories. The puzzle of how memories persist in the brain has long been of interest to Sakai. Researchers had previously demonstrated, in both rodents and flies, that the production of new proteins is necessary for maintaining long-term memories, but Sakai wondered how this process persisted over several days given cells’ molecular turnover. Maybe, he thought, an environmental stimulus, such as the light-dark cycles, periodically triggered protein production to enable memory formation and storage. Sakai and his colleagues conducted a series of experiments to see how constant darkness would affect the ability of Drosophila melanogaster to form long-term memories. Male flies exposed to light after interacting with an unreceptive female showed reduced courtship behaviors toward new female mates several days later, indicating they had remembered the initial rejection. Flies kept in constant darkness, however, continued their attempts to copulate. The team then probed the molecular mechanisms of these behaviors and discovered a pathway by which light activates cAMP response element-binding protein (CREB)—a transcription factor previously identified as important for forming long-term memories—within certain neurons found in the mushroom bodies, the memory center in fly brains. © 1986–2020 The Scientist.

Keyword: Learning & Memory; Biological Rhythms
Link ID: 27248 - Posted: 05.16.2020

By Alexandra Jacobs THE SHAPELESS UNEASE A Year of Not Sleeping By Samantha Harvey As if in unwitting aid of the malady they address, books about insomnia tend to be very dull indeed. Many are stuffed with statistics and unhelpful suggestions, like one of those oversize polyester-plumped sham pillows you see on the fancier beds — and just as likely to be flung in frustration to the floor. Samantha Harvey’s memoir of sleeplessness is more like a small and well-worn eiderdown quilt: It might not cover everything, but it both cools and warms, lofts and lulls, settling gradually on its inhabitant with an ethereal solidity. Harvey is a well-regarded novelist in the United Kingdom, and perhaps the only part of this book that feels a little lumpy and uncomfortable is her working out in its pages an O. Henry-like short story about a husband who loses his wedding ring while robbing an A.T.M. More compelled by her predicament, namely stretch after stretch of not only little sleep (or “petite nuit,” as the French more melodiously put it) but no sleep at all, I found it difficult to care about this fictional character, or figure out if his crime and punishment represented anything larger about what disenchanted millennials have taken to describing as “late-stage capitalism.” Not for nothing does the author’s own experience take place in 2016, that epoch of political shock during which a majority of her compatriots voted to leave the European Union, a.k.a. Brexit (“Why isn’t it called Ukexit,” Harvey wonders with the petty irritability of the sleep-deprived), and Donald J. Trump was elected over the pond. That these events have since been outdone by arrival of the coronavirus pandemic, with its attendant sleep disorders, only amplifies this small volume’s relevance and power. © 2020 The New York Times Company

Keyword: Sleep
Link ID: 27242 - Posted: 05.12.2020

A small study funded by the National Institutes of Health suggests that sleep problems among children who have a sibling with autism spectrum disorder (ASD) may further raise the likelihood of an ASD diagnosis, compared to at-risk children who do not have difficulty sleeping. Previous research has shown that young children who have a sibling with ASD are at a higher risk for also being diagnosed with the condition. The study appears in The American Journal of Psychiatry. If confirmed by other studies, the findings may give clinicians a tool to identify sleep problems early and provide interventions to reduce their effects on the health and development of children with autism. The findings may also provide insights into the potential role of sleep problems in the development of ASD. The study was conducted by Annette M. Estes, Ph.D., of the University of Washington Autism Center in Seattle, and colleagues in the NIH Autism Centers of Excellence Infant Brain Imaging Study Network. NIH funding was provided by the Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD) and the National Institute of Mental Health. “The results are a promising lead,” said Alice Kau, Ph.D., of NICHD’s Intellectual and Developmental Disabilities Branch. “If confirmed by more in-depth studies, patterns of sleep disturbance in early life might be used to pinpoint increased risk for ASD among young children already at risk because they have a sibling with ASD.” The researchers analyzed data from a long-term study of children who do and do not have siblings with ASD. When the children were 6 and 12 months of age, parents were asked to respond to an infant temperament questionnaire that asks how much difficulty their child has falling asleep at bedtime and falling back to sleep after waking up during the night. At these time intervals, the children also received MRI scans to track their brain development. At 24 months, the children were assessed for ASD.

Keyword: Autism; Sleep
Link ID: 27238 - Posted: 05.08.2020

African Americans with severe sleep apnea and other adverse sleep patterns are much more likely to have high blood glucose levels — a risk factor for diabetes — than those without these patterns, according to a new study funded in part by the National Heart, Lung, and Blood Institute (NHLBI), part of the National Institutes of Health. The findings suggest that better sleep habits may lead to better blood glucose control and prove beneficial for type 2 diabetes prevention and diabetes management in African Americans, who are at higher risk for type 2 diabetes than other groups. They also point to the importance of screening for sleep apnea to help fight the potential for uncontrolled blood sugar in this high-risk group, the researchers said. Previous studies have linked disturbed sleep patterns, including sleep apnea, to increased blood glucose levels in white and Asian populations. But this new study is one of the few to use objective measurements to link these disturbed sleep patterns to increased blood glucose levels in black men and women, the researchers said. Their findings appear online on April 28 in the Journal of the American Heart Association. “The study underscores the importance of developing interventions to promote regular sleep schedules, particularly in those with diabetes,” said Yuichiro Yano, M.D., Ph.D., the lead study author and a researcher in the Department of Family Medicine and Community Health at Duke University. “It also reaffirms the need to improve the screening and diagnosis of sleep apnea, both in African Americans and other groups.”

Keyword: Sleep
Link ID: 27219 - Posted: 04.29.2020

by Peter Hess Early sleep problems predict repetitive behaviors later in childhood1. And toddlers who overreact or underreact to sensory stimuli have more repetitive behaviors and other autism traits later on2. Together, the findings from two independent studies suggest that early behavioral differences may set the stage for restricted and repetitive behaviors, a core characteristic of autism also associated with other conditions of brain development. The studies also highlight areas for early intervention, particularly if further research identifies causal links between these traits. “Addressing sleep problems might be able to improve trajectories,” says Annette Estes, director of the University of Washington Autism Center in Seattle, who led the sleep study. Autistic children are twice as likely to have trouble sleeping as typical children. Their poor sleep has been linked to severe traits including severe repetitive and restricted behaviors. The new study is unusual in that it links sleep problems with a subset of ‘higher-order’ restrictive and repetitive behaviors that include restricted interests, rituals or routines and an insistence on sameness. The study involved 38 autistic children aged 2 to 6 years and 19 children with developmental delay aged 2 to 4. Parents completed a standardized questionnaire about their children’s sleep problems at age 4 — including difficulty falling asleep, short sleep duration and parasomnias such as sleepwalking and night terrors. Clinicians assessed autism traits, including repetitive behaviors, around age 2 and at two or three later points in time. © 2020 Simons Foundation

Keyword: Autism; Sleep
Link ID: 27208 - Posted: 04.22.2020

Brandie Weikle · CBC News The strains of worry and upended routine during the COVID-19 crisis aren't exactly helping people sleep well at night. You or someone you love may be battling the novel coronavirus, or your employment may have been blown up by business shutdowns and stay-home directives. You're juggling health care with child care and cabin fever. Even if you're healthy and gainfully employed, pandemic living isn't easy. "Everyone's routine is being disrupted. It's a severely stressful event," said Dr. Atul Khullar, an Edmonton psychiatrist and senior consultant for MedSleep, a group of sleep clinics. This provokes anxiety and stress, exacerbating any pre-existing mental health and insomnia problems, or causing new ones, he said. "And for some people it can be very traumatizing. They're facing losing their livelihoods. They're faced with losing their way of life. Notwithstanding that your kids are home. It's just stressor after stressor after stressor." This isn't the stuff of which sweet dreams are made. If you're a parent wondering how to talk to your kids about the coronavirus, here's a video that'll help start the conversation. 1:27 Whether or not you're occupied at any given moment with the task or activity in front of you, below the surface remains the psychological weight of being in unprecedented and life-altering times, said Khullar. "It's kind of this dull ache for a lot of people, and you can only ignore it so much." ©2020 CBC/Radio-Canada

Keyword: Sleep
Link ID: 27171 - Posted: 04.06.2020

By Adam Popescu Many people spend their nights now tossing and turning, struggling to unglue from the constant scroll of coronavirus news updates. But, while there is no body or life hack to make you impervious to the touch of disease, we do know that sleep is key to helping our bodies stay healthy. “Sleep is an essential part of protection from and response to any infection,” said Douglas B. Kirsch, a neurologist and former president of the American Academy of Sleep Medicine. But still, he hears you: “Sleep is hard when anxiety levels are high, such as in the case of a pandemic.” There are some answers as to what you can do now. You may not like them. Create and maintain a very consistent sleep practice and schedule that works for you. The more consistent your wake-up time, the more consistent your body functions. The National Sleep Foundation recommends sticking to a sleep schedule, and here’s a simple way to do it: Set a regular bedtime. Pair it with a set time to wake. (As many people aren’t currently commuting, this might be easier than normal.) Set yourself up for success by doing the little things: use blackout curtains if you’re sleeping while it’s bright, ditto to earplugs or a sleep mask (Wirecutter, a company owned by The New York Times that judges products, recommends this sleep mask, but even a light pillow or T-shirt works in a pinch). No matter what you do, make your bedroom very comfortable and very dark. Are you easily awakened? Use a fan or a repeated track on Spotify for white noise. Still, if you’re tired, get sleep while you can. “If you’re tired during the day, get your rest then,” said Janet Mullington, a professor in the department of neurology at Harvard Medical School. © 2020 The New York Times Company

Keyword: Sleep
Link ID: 27144 - Posted: 03.27.2020

By Allison Hirschlag Everyone likes a good nap now and then, right? Whether you nod off during a boring movie, or rest your head on your desk at work for 20 minutes or so to fight the afternoon slump, naps can revitalize you in a major way. One study even showed they can boost performance and memory regulation better than caffeine. This all sounds great in theory, but many people — myself included — find naps do the opposite. I wake up from naps feeling like I’m in the throes of a New Year’s Day-strength hangover. It takes me at least 20 minutes to recover from them, and I never end up seeing any of the benefits. Even when I timed my nap to be no more than 30 minutes — the nap length sleep experts claim is the most beneficial — I came out of it certain I was experiencing the early stages of the flu (I wasn’t). Naturally, I’ve always been a little jealous of the people who take naps and wake up feeling like a million bucks. I’m a healthy, youngish, childless woman who regularly sleeps seven to eight hours a night — why don’t naps work for me? The short answer is that some adults are genetically predisposed to need more hours of continuous sleep than others (I’m leaving children out of this because, as growing bodies, they naturally need more sleep). According to a study by the National Heart, Lung and Blood Institute, at least 80 genes appear to be involved in sleep regulation, which “suggests that sleep duration in natural populations can be influenced by a wide variety of biological processes.” Simply put, sleep duration needs vary considerably because they’re based on a broad spectrum of genetic differences.

Keyword: Sleep; Genes & Behavior
Link ID: 27105 - Posted: 03.09.2020

By Laura Sanders Here’s something neat about sleeping sheep: Their brains have fast zags of neural activity, similar to those found in sleeping people. Here’s something even neater: These bursts zip inside awake sheep’s brains, too. These spindles haven’t been spotted in healthy, awake people’s brains. But the sheep findings, published March 2 in eNeuro, raise that possibility. The purpose of sleep spindles, which look like jagged bursts of electrical activity on an electroencephalogram, isn’t settled. One idea is that these bursts help lock new memories into the brain during sleep. Daytime ripples, if they exist in people, might be doing something similar during periods of wakefulness, the researchers speculate. Jenny Morton, a neurobiologist at the University of Cambridge, and her colleagues studied six female merino sheep with implanted electrodes that spanned their brains. The team collected electrical patterns that emerged over two nights and a day. As the sheep slept, sleep spindles raced across their brains. These spindles are akin to those in people during non-REM sleep, which accounts for the bulk of an adult’s sleeping night (SN: 8/10/10). But the electrodes also caught spindles during the day, when the sheep were clearly awake. These “wake” spindles “looked different from those we saw at night,” Morton says, with different densities, for instance. Overall, these spindles were also less abundant and more localized, captured at single, unpredictable spots in the sheep’s brains. © Society for Science & the Public 2000–2020.

Keyword: Sleep; Evolution
Link ID: 27089 - Posted: 03.03.2020

By Rachel Cericola A year ago, I was diagnosed with nasal polyps and regularly snored like a wild boar. I’ve had the polyps removed, but the snoring continues. I’m not alone. According to Principles and Practice of Sleep Medicine (Fifth Edition), “about 40 percent of the adult population” snores. Sometimes my snoring wakes up my husband (and vice versa), so I decided to try out six popular over-the-counter anti-snoring contraptions. To get a baseline measurement of how much I was snoring without any intervention, I used SnoreLab, a highly rated app that listens for snoring sounds, records clips, and analyzes your resting audio. After calculating an average of four nights’ intervention-free snoring readings to get a starting “sleep score,” I then slept with each anti-snoring device for several nights and tracked my SnoreLab results against that baseline. (Note that some of these devices may work for you and not me — and none of them should be used to treat sleep apnea. If you’re having restless sleep, gasping awake, or even feeling tired and foggy in the daytime, see a doctor.) While longer-term testing is needed before we could confidently recommend any of these, a few devices showed promise in our preliminary — and far from scientific — trials. Here’s how they did, in order of how much I found they helped: Smart Nora, $329 at the time of publication This system will slightly move your head when it catches you snoring. It includes a wireless, mic-equipped device that can sit bedside or be wall-mounted to detect snoring. Once it does that, it communicates with an under-bed base station that pumps air through a tube to an insert that lives inside your pillow. That motion gently adjusts your head position to reduce snoring (in my case, it effectively did so without waking me up). It sounds bizarre, but this was actually the most effective device I tried, cutting my total snoring in half, according to my SnoreLab sleep scores. It is also the most expensive. There are many options for personalization, which we will continue to test. © 2020 The New York Times Company

Keyword: Sleep
Link ID: 27052 - Posted: 02.20.2020

Shannon Bond If you're having a hard time falling asleep, that sleep tracker on your wrist might be to blame. And there's a name for this new kind of insomnia of the digital age: orthosomnia. It's "when you just really become fixated on having this perfect sleep via tracker," said Seema Khosla, medical director at the North Dakota Center for Sleep. "And then you start worrying about it, and you wind up giving yourself insomnia." Sleep trackers have become increasingly popular. They come in the form of watches, wristbands, rings and even mattresses. The gadgets measure how you breathe, how fast your heart is beating, how much you're tossing and turning. They crunch that data to produce a sleep score, usually through a smartphone app. But in an irony of our digital lifestyles, for some people, perfecting that sleep score becomes an end unto itself — so much so that they can lose sleep over it. Khosla sees this is her own practice as a sleep doctor. Stressed-out patients complain they are aiming for a sleep score of 100 but are getting only 80. It keeps them up at night. She has a simple solution. "I'll ask them just to put their tracker away for a couple of weeks. And honestly, sometimes you can just see the relief on their faces," she said. Kathrin Hamm experienced this problem firsthand. She was traveling around the world as an economist for the World Bank, and getting good sleep was a priority. © 2020 npr

Keyword: Sleep
Link ID: 27043 - Posted: 02.18.2020

By Elizabeth Pennisi Scientists seeking the origins of sleep may have uncovered important clues in the Australian bearded dragon. By tracing sleep-related neural signals to a specific region of the lizard’s brain—and linking that region to a mysterious part of the mammalian brain—a new study suggests complex sleep evolved even earlier in vertebrate evolution than researchers thought. The work could ultimately shed light on the mechanisms behind sleep—and pave the way for studies that may help humans get a better night’s rest. “Answers to the questions raised and reframed by this research seem extremely likely to be significant in many ways, including clinically,” says Stephen Smith, a neuroscientist at the Allen Institute who was not involved with the new study. Mammals and birds have two kinds of sleep. During rapid eye movement (REM) sleep, eyes flutter, electrical activity moves through the brain, and, in humans, dreaming occurs. In between REM episodes is “slow wave” sleep, when brain activity ebbs and electrical activity synchronizes. This less intense brain state may help form and store memories, a few studies have suggested. In 2016, Gilles Laurent, a neuroscientist at the Max Planck Institute for Brain Research, discovered that reptiles, too, have both kinds of sleep. Every 40 seconds, central bearded dragons (Pogona vitticeps) switch between the two sleep states, he and his colleagues reported. © 2019 American Association for the Advancement of Science

Keyword: Sleep; Evolution
Link ID: 27037 - Posted: 02.13.2020

By Shola Lawal These are tough times for fireflies. Like a lot of other insects, they face increasing threats from habitat loss, pesticides and pollution. But they also have a problem that’s unique to luminous bugs: It’s getting harder for them to reproduce because light pollution is outshining their mating signals. Fireflies, it turns out, use their special glowing powers in courtship: Males light up to signal availability and females respond with patterned flashes to show that they’re in the mood. But bright light from billboards, streetlights and houses is interfering and blocking potential firefly couples from pairing up. The problem can reach far from big cities: Bright light gets diffused in the atmosphere and can be reflected into the wilderness. In addition to messing with mating signals, it also disrupts the feeding patterns of the females of some species that glow to attract and eat males. The finding was part of a study published Monday in the journal BioScience. The study, by researchers at Tufts University and the International Union for Conservation of Nature, warned that fireflies could eventually face extinction globally because of multiple threats, including light pollution and habitat loss and habitat degradation from insecticides and chemical pollution. Many insects are affected by habitat loss, but fireflies have it particularly bad, said Sara M. Lewis, a biology professor at Tufts and the lead researcher on the study. “Some fireflies get hit especially hard when their habitat disappears because they need special conditions to complete their life cycle,” she said. Fireflies are a type of beetle. There are more than 2,000 species of them, found mainly in wetlands. But mangrove forests and marshes around the world are increasingly vanishing to make way for cash crops like palm oil, according to the new study. © 2020 The New York Times Company

Keyword: Sexual Behavior; Biological Rhythms
Link ID: 27018 - Posted: 02.04.2020

By Jade Wu Savvy Psychologist This week, let’s ask the million-dollar question: How much sleep do you really need? We all know sleep is important. Shakespeare called it the “sore labor’s bath, balm of hurt minds, great nature’s second course, chief nourisher in life’s feast.” Less poetically, headlines these days seem to be shouting: “Sleep deprivation will make you slower and dumber!” “It will give you Alzheimer's disease and heart attacks!” One mattress advertisement I saw simply said, “You can only live seven days without sleep.” Yikes. Talk about pressure to perform! Fear-mongering aside, there is good evidence that sleep is important for health, well-being, and performance. A recent meta-analysis including over 1600 participants confirmed that sleep restriction is associated with poorer attention and thinking. We’ve known for decades that sleep deprivation disrupts mood. For example, it can trigger manic episodes in those with bipolar disorder. And we’re learning now, from researchers in Sweden and Germany, that insufficient sleep can even affect the microbiota in your gut. But how much sleep is enough? Is there such a thing as too much sleep? If you ask Dr. Google, you’ll get over a billion answers. (That’s right; “billion” with a “b.”) The most common answer seems to be “eight hours.” That seems pretty straightforward. But where does this number come from? And if you’re thinking, “Dr. Google hasn’t examined me; how would she know how much sleep I need,” then you’re asking exactly the right question. © 2020 Scientific American

Keyword: Sleep
Link ID: 26977 - Posted: 01.22.2020

By Harry Guinness The world isn’t made for night owls. You struggle into work in the dark hours before 10 a.m. — or your morning coffee — and you’re greeted by some chipper person who has already been to the gym and is six items into his to-do list. I used to fantasize about fitting punishments for such morning people, but in the last two years I’ve seen the (morning) light, and I’ve become one of them. If you love staying up late but hate crawling through your mornings in a haze, here’s how you can do it too. After a long, draining day you finally get home, settle down in front of the TV and throw on whatever season you’re currently bingeing. Heaven. But then, when a reasonable bedtime rolls around, you don’t want to stop. It has been a hard day, aren’t you entitled to just one more episode? So you push play, trade a bit of sleep for more Netflix time and continue the cycle that keeps you tired all the time. Dr. Alex Dimitriu, founder of the Menlo Park Psychiatry and Sleep Medicine clinic, explained it like this: “Long days leave us tired and exhausted, but the reality is, our days would be less hard, and less exhausting, if we weren’t so tired through them. The trouble with being a night owl is that your sleep gets clipped in the morning hours, where most of the precious REM or dream sleep occurs. Instead of sleeping seven or eight hours per night, most night owls get forced to sleep five or six — with a hard start time in the morning.” Dr. Dimitriu can’t stress enough just how important REM sleep is. It’s “the key to our emotional and creative energy” and comparable to “self-therapy,” he said, adding that it “balances us out in more ways than I can describe” and that without enough of it, our memory and moods take a hit. If you have the freedom to wake up when you like, then things are different, but if that extra Netflix episode is forcing you to cut your sleep short, then you should try to do something about it. © 2020 The New York Times Company

Keyword: Biological Rhythms; Sleep
Link ID: 26973 - Posted: 01.21.2020