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National Institutes of Health scientists have used human skin cells to create what they believe is the first cerebral organoid system, or “mini-brain,” for studying sporadic Creutzfeldt-Jakob disease (CJD). CJD is a fatal neurodegenerative brain disease of humans believed to be caused by infectious prion protein. It affects about 1 in 1 million people. The researchers, from NIH’s National Institute of Allergy and Infectious Diseases (NIAID), hope the human organoid model will enable them to evaluate potential therapeutics for CJD and provide greater detail about human prion disease subtypes than the rodent and nonhuman primate models currently in use. Human cerebral organoids are small balls of human brain cells ranging in size from a poppy seed to a small pea. Their organization, structure, and electrical signaling are similar to brain tissue. Because these cerebral organoids can survive in a controlled environment for months, nervous system diseases can be studied over time. Cerebral organoids have been used as models to study Zika virus infection, Alzheimer’s disease, and Down syndrome. In a new study published in Acta Neuropathologica Communications, scientists at NIAID’s Rocky Mountain Laboratories discovered how to infect five-month-old cerebral organoids with prions using samples from two patients who died of two different CJD subtypes, MV1 and MV2. Infection took about one month to confirm, and the scientists monitored the organoids for changes in health indicators, such as metabolism, for more than six months. By the end of the study, the scientists observed that seeding activity, an indication of infectious prion propagation, was present in all organoids exposed to the CJD samples. However, seeding was greater in organoids infected with the MV2 sample than the MV1 sample. They also reported that the MV1-infected organoids showed more damage than the MV2-infected organoids.

Keyword: Prions; Development of the Brain
Link ID: 26331 - Posted: 06.15.2019

By Simon Makin Better Memory through Electrical Brain Ripples Hippocampus Neuron, computer illustration Credit: Kateryna Kon Getty Images Specific patterns of brain activity are thought to underlie specific processes or computations important for various mental faculties, such as memory. One such “brain signal” that has received a lot of attention recently is known as a “sharp wave ripple”—a short, wave-shaped burst of high-frequency oscillations. Researchers originally identified ripples in the hippocampus, a region crucially involved in memory and navigation, as central to diverting recollections to long-term memory during sleep. Then a 2012 study by neuroscientists at the University of California, San Francisco, led by Loren Frank and Shantanu Jadhav, the latter now at Brandeis University, showed that the ripples also play a role in memory while awake. The researchers used electrical pulses to disrupt ripples in rodents’ brains, and showed that, by doing so, performance in a memory task was reduced. However, nobody had manipulated ripples to enhance memory—until now, that is. Researchers at NYU School of Medicine led by neuroscientist György Buzsáki have now done exactly that. In a June 14 study in Science, the team showed that prolonging sharp wave ripples in the hippocampus of rats significantly improved their performance in a maze task that taxes working memory—the brain’s “scratch pad” for combining and manipulating information on the fly. “This is a very novel and impactful study,” says Jadhav, who was not involved in the research. “It’s very hard to do ‘gain-of-function’ studies with physiological processes in such a precise way.” As well as revealing new details about how ripples contribute to specific memory processes, the work could ultimately have implications for efforts to develop interventions for disorders of memory and learning. © 2019 Scientific American

Keyword: Learning & Memory
Link ID: 26330 - Posted: 06.15.2019

By Carl Zimmer Last week, ladybugs briefly took over the news cycle. Meteorologists at the National Weather Service were looking over radar images in California on the night of June 4 when they spotted what looked like a wide swath of rain. But there were no clouds. The meteorologists contacted an amateur weather-spotter directly under the mysterious disturbance. He wasn’t getting soaked by rain. Instead, he saw ladybugs. Everywhere. Radar apparently had picked up a cloud of migrating ladybugs spread across 80 miles, with a dense core ten miles wide floating 5,000 feet to 9,000 feet in the air. As giant as the swarm was, the meteorologists lost track of it. The ladybugs disappeared into the night. Compared to other animal migrations, the migrations of insects are a scientific mystery. It’s easy to spot a herd of wildebeest making its way across the savanna. Insects, even in huge numbers, move from place to place without much notice. One day you look around, and ladybugs are everywhere. “The migrations themselves are totally invisible,” said Jason Chapman, an ecologist at the University of Exeter in Britain. Dr. Chapman and his colleagues are using radar to bring insect migrations to light. The scientists help run a unique network of small radar stations in southern England designed to scan the sky 24 hours a day, spotting insects flying overhead. “These radars are fantastic,” said Dr. Chapman. “We have a lot of information about every individual insect that flies over overhead, including a measure of the shape and a measure of their size.” © 2019 The New York Times Company

Keyword: Animal Migration
Link ID: 26329 - Posted: 06.14.2019

Sara Reardon A medical imaging device that can create 3D renderings of the entire human body in as little as 20 seconds could soon be used for a wide variety of research and clinical applications. The modified positron emission tomography (PET) scanner is faster than conventional PET scans — which can take an average of 20 minutes — and requires less radiation exposure for the person being imaged. Researchers presented video taken by the device last week at the US National Institutes of Health’s High-Risk, High-Reward Research Symposium in Bethesda, Maryland. The machine could be especially helpful for imaging children, who tend to wiggle around inside a scanner and ruin the measurements, as well as for studies of how drugs move through the body, says Sanjay Jain, a paediatrician and infectious-disease physician at Johns Hopkins University in Baltimore, Maryland. Standard PET scanners detect γ-rays from radioactive tracers that doctors inject into the person being imaged. The person’s cells take up the molecule and break it down, releasing two γ-rays. A ring-shaped detector positioned around the person measures the angle and speed of the rays and reconstructs their origin, creating a 3D map of the cells that are metabolizing the molecule. The ring is just 25 centimetres thick, however, so physicians can image only a small portion of the body at a time. Capturing larger areas requires them to dose the person with more of the radioactive molecule ― it decays quickly, which means the signal fades fast ― and move them back and forth through the ring. © 2019 Springer Nature Publishing AG

Keyword: Brain imaging
Link ID: 26328 - Posted: 06.14.2019

By Karen Zraick and Sarah Mervosh Are you sabotaging your sleep in your quest to improve it? Many new tools are becoming available to monitor your sleep or help you achieve better sleep: wearable watches and bands; “nearable” devices that you can place on your bed or nightstand; and apps that work by monitoring biometric data, noise and movement. They can remind you to start winding down, or generate a report on your night’s slumber. But some sleep specialists caution that these apps and devices may provide inaccurate data and can even exacerbate symptoms of insomnia. Fiddling with your phone in bed, after all, is bad sleep hygiene. And for some, worrying about sleep goals can make bedtime anxiety even worse. There’s a name for an unhealthy obsession with achieving perfect sleep: orthosomnia. It was coined by researchers from Rush University Medical School and Northwestern University’s Feinberg School of Medicine in a 2017 case study published in the Journal of Clinical Sleep Medicine. Dr. Kelly Baron, one of the paper’s authors and the director of the University of Utah’s behavioral sleep medicine program, said that sleep trackers can be helpful in identifying patterns. She herself tracks her bedtime with a Fitbit. But she said she had noticed a trend of patients complaining based on unverified scores, even for things like the amount of deep sleep, which varies by individual. “People were putting a lot of stock in what it was telling them,” she said. “Like, ‘I’m afraid I’m not getting enough deep sleep. There’s something wrong with me.’” As gadgets proliferate, so do concerns The flood of data and buzzwords can easily become confusing: sleep debt percentages, heart rate dips, sleep rhythms, graphs of sleep disruption and comparisons to other users. © 2019 The New York Times Company

Keyword: Sleep
Link ID: 26327 - Posted: 06.14.2019

By Jan Hoffman An association between weed and the dead turns out to have been established long before the 1960s and far beyond a certain ur-band’s stomping grounds in San Francisco. Researchers have identified strains of cannabis burned in mortuary rituals as early as 500 B.C., deep in the Pamir mountains in western China, according to a new study published Wednesday. The residue had chemical signatures indicating high levels of tetrahydrocannabinol (THC), the plant’s most psychoactive, or mood-altering, compound. You think the Grateful Dead were the first to wonder “what in the world ever became of sweet Jane?” That CBD gummies to assuage the anxious are anything new? That puffs of elevated consciousness started with Rocky Mountain highs? Nah. “Modern perspectives on cannabis vary tremendously cross-culturally, but it is clear that the plant has a long history of human use, medicinally, ritually and recreationally over countless millennia,” said Robert Spengler, an archaeobotanist at the Max Planck Institute for the Science of Human History in Jena, Germany, who worked on the study. Cannabis stems and seeds had previously been found at a handful of burial sites around Eurasia, but the evidence at the Pamir cemetery, verified by advanced scientific technology, shows an even more direct connection between the plant and early ritual. The new findings expand the geographical range of cannabis use within the broader Central Asian region, said Mark Merlin, a professor of botany at the University of Hawaii at Manoa, who did not work on the research. © 2019 The New York Times Company

Keyword: Drug Abuse
Link ID: 26326 - Posted: 06.14.2019

By Anahad O’Connor Many nutrition experts blame processed foods for the obesity epidemic, suggesting that a return to home cooking would turn it around. But now some researchers are pushing back against that idea, arguing that it oversimplifies the obstacles that poor and middle-class families face. The case against processed foods has been growing. A flurry of studies last month provided new evidence that these foods, which are typically loaded with salt, sugar, fat and chemical additives, heighten the risk of obesity and chronic disease. Scientists at the National Institutes of Health found that people ate more calories and quickly gained weight on a diet of mostly ultra-processed foods like frozen entrees, diet beverages, fruit juices, pastries, baked potato chips, canned foods and processed meats. Then a pair of large studies in the journal BMJ showed that people who ate significant amounts of these foods had increased mortality rates and cardiovascular disease compared to people who avoided them. These findings and others prompted health experts — including Dr. Francis Collins, the director of the N.I.H. — to urge Americans to limit their intake of ultra-processed foods. But that might be easier said than done. Highly processed foods have become the dominant food source for many Americans, accounting for almost 60 percent of the calories we eat. Americans across the socioeconomic spectrum consume them in increasing amounts. But studies show that their intake is highest among low-income families. Many households depend on them because they are cheap, convenient and, in some cases, their only option. © 2019 The New York Times Company

Keyword: Obesity
Link ID: 26325 - Posted: 06.12.2019

By Caterina Gawrilow, Sara Goudarzi Those affected by attention deficit hyperactivity disorder (ADHD) are clinically thought of as inattentive, hyperactive and impulsive. However, people with ADHD are also perceived as being very spontaneous, curious, inquisitive, enthusiastic, lively and witty, a perception that creates an impression they are more creative than those without ADHD. But is there truth to this idea? Creativity is generally the ability to generate something original and unprecedented. The ideas must not only be new and surprising, but also useful and relevant. Among other things, creativity comes through intensive knowledge and great motivation in a particular field, be it painting, music or mathematics. For years, both laypersons and scientists have been fascinated by the proverbial proximity of genius and madness. According to psychologist Dean Keith Simonton from the University of California, Davis, unusual and unexpected experiences, such as psychological difficulties and psychiatric stays, are an important characteristic of people who create masterpieces. Advertisement Two core symptoms, inattention and impulsiveness, suggest a connection between creativity and ADHD. Inattention, which occurs more frequently in those affected with the disorder, likely leads to mind wandering, or the drifting of thoughts from an activity or environment. Such drifting can lead to new, useful and creative ideas. © 2019 Scientific American

Keyword: ADHD
Link ID: 26324 - Posted: 06.12.2019

Strobe lighting at music festivals can increase the risk of epileptic seizures, researchers have warned. The Dutch team said even people who have not been diagnosed with epilepsy might be affected. Their study was prompted by the case of a 20-year-old, with no history of epilepsy, who suddenly collapsed and had a fit at a festival. The Epilepsy Society said festivals should limit lighting to the recommended levels. Epilepsy is a condition that affects the brain. There are many types, and it can start at any age. Around 3% of people with epilepsy are photosensitive, which means their seizures are triggered by flashing or flickering lights, or patterns. The Health and Safety Executive recommends strobe lighting should be kept to a maximum of four hertz (four flashes per second) in clubs and at public events. 'Life-affirming' The researchers studied electronic dance music festivals because they often use strobe lighting. They looked at data on people who needed medical care among the 400,000 visitors to 28 day and night-time dance music festivals across the Netherlands in 2015. The figures included 241,000 people who were exposed to strobe lights at night-time festivals. Thirty people at night-time events with strobe lighting had a seizure, compared with nine attending daytime events. The team, led by Newel Salet of the VU Medical Centre in Amsterdam, writing in BMJ Open, said other factors could increase the risk of seizures. But they added: "Regardless of whether stroboscopic lights are solely responsible or whether sleep deprivation and/or substance abuse also play a role, the appropriate interpretation is that large [electronic dance music] festivals, especially during the night-time, probably cause at least a number of people per event to suffer epileptic seizures." They advise anyone with photosensitive epilepsy to either avoid such events or to take precautionary measures, such as getting enough sleep and not taking drugs, not standing close to the stage, and leaving quickly if they experience any "aura" effects. © 2019 BBC

Keyword: Epilepsy; Vision
Link ID: 26323 - Posted: 06.12.2019

Katarina Zimmer Occasionally, as the nematode worm C. elegans meanders across rotten fruit on the prowl for bacteria to eat, it comes across ones it shouldn’t dine on. Some bacteria are lethal to the animals when ingested, and unfortunately, the worms can’t always distinguish them from the nutritious kind until it’s too late. Nevertheless, this doesn’t stop them from teaching their young not to make the same mistake, researchers recently realized when watching the nematodes in the lab. Before the animals die from the pathogen, they often lay eggs. These offspring, researchers at Princeton University observed, consistently avoid that particular bacterial species. Evidently, pathogen avoidance—a behavioral habit the mothers learned towards the end of their lifetime—can be transmitted to the next generation, aiding their survival. But it’s not a hard-wired trait; instead, an epigenetic mechanism involving small RNAs appears to be responsible. That’s the finding of a paper published in Cell yesterday (June 6). Alongside it in the journal, a group at Tel Aviv University also reports on transgenerational inheritance of behavior traits in C. elegans. This team took a different approach, demonstrating how a small RNA–based mechanism allows information from the nervous system to be transmitted to germline cells and into future generations. While it’s known that traits involved in immunity and stress can be inherited across generations in C. elegans, the two papers are among the first to show that complex behaviors can be transmitted in the same way. © 1986–2019 The Scientist

Keyword: Epigenetics
Link ID: 26322 - Posted: 06.11.2019

By Lenny Bernstein Five years ago, a study of death certificate data attracted notice for suggesting that states that passed medical marijuana laws saw 25 percent fewer opioid overdose deaths on average than states that barred medical cannabis. The authors were careful to point out that this finding was only a correlation, an intriguing hint at something that needed further exploration. There was no way to establish whether the availability of medical cannabis in some states protected against overdosing on harder drugs, even if some people used marijuana for pain. Nevertheless, the cannabis industry took up the study to help win passage of medical cannabis laws in more states, even as medical experts expressed skepticism. In a 2018 report, for example, Maryland’s medical marijuana commission found “no credible scientific evidence” that marijuana could treat opioid addiction. Now comes a study from Stanford University School of Medicine showing that when researchers looked at a longer period of time, states that introduced medical marijuana actually had 23 percent more deaths from opioid overdoses. The new work appears to be a cautionary tale about inferring cause and effect — wanting research to show something it can’t because the nation is in the grip of a deadly opioid epidemic or because there is money to be made by offering possible solutions. The nation’s opioid crisis, now more than two decades old, has taken more than 400,000 lives, according to government data. “A lot of people interpreted the first study as causal because it’s congenial to their goals,” said Chelsea L. Shover, a postdoctoral fellow in psychiatry who was part of the Stanford research team. “It did not say that one is causing the other.” © 1996-2019 The Washington Post

Keyword: Drug Abuse
Link ID: 26321 - Posted: 06.11.2019

By Malia Wollan “Fasting is mental over physical, just like basketball and most other stuff in life,” says Enes Kanter, the 6-foot-11 center for the Portland Trail Blazers. Raised in Turkey, Kanter, 27, is a Muslim who has fasted from sunrise to sunset during the month of Ramadan since he was 8. This season, Ramadan aligned with the N.B.A. playoffs, so Kanter fasted through seven playoff games. During the year he forgoes food and water a day or two a week. “Don’t be scared to try it,” he says. Intermittent fasting has become a trendy tool for losing weight and boosting mental acuity and productivity. Adherents typically restrict eating to a window of eight or fewer hours during the day, or they limit caloric intake a few days per week. Studies suggest that following such diets can lead to weight loss and reduced risk of cardiovascular disease and may even protect against age-related neurological disorders like Alzheimer’s. For his part, though, Kanter is trying desperately not to lose any weight. His team’s trainers worried about him going 16 hours without food or water on game days, and so before dawn and twice after dark he partook of carbohydrate feasts: pasta, quesadillas, burritos, sandwiches, sports drinks and nutrition bars. “As many calories as I can put in my body,” he says. Don’t fast if you are at all prone to eating disorders or have a medical condition that might make it dangerous. (While Ramadan fasting is compulsory for Muslims, exceptions are made for children, pregnant women and the ill, among others.) Break your fast carefully by resisting the hurried, gobbler mind-set. “Don’t lose control of yourself,” Kanter says. “Go slow.” Start with lighter fare like soup or salad. Wait 10 minutes before beginning heavier courses. © 2019 The New York Times Company

Keyword: Obesity
Link ID: 26320 - Posted: 06.11.2019

By Sarah Baird Few topics occupy pregnant women’s minds in the months leading up to birth more than devising a plan for pain management during labor. In the United States, the options during delivery have long been pretty limited. On one side of the dichotomy is a completely unmedicated childbirth, where visualization and breathing techniques offer a mind-over-matter approach to labor pain. On the other side, epidurals are the pain-eliminating gold standard — but can come with plenty of trade-offs. Across the world, though, nitrous oxide (yes, “laughing gas”) has long been standard — dating back to the turn-of-the-century — in delivery rooms, allowing women to help mitigate the pain of labor while remaining present and, perhaps best of all, maintaining their sense of control. Now, this low-stakes form of delivery room relief is finally taking hold in the United States as women seek out a wider range of options for their birthing experience. Nitrous oxide is a blend of 50 percent nitrous and 50 percent oxygen that women are able to self-administer during labor by holding a face mask over their nose and mouth and breathing deeply. (The 50/50 ratio is a set concentration and cannot be raised or lowered, unlike the dialed system in a dentist’s office which can be increased up to 70 percent nitrogen.) The option, unlike other types of pain relief, requires no I.V., does not limit mobility and will not slow contractions. The effects of nitrous kick in within 30 to 50 seconds of beginning inhalation, providing a very different form of pain management than other methods available. “It’s been described as a dissociative effect, so it reduces anxiety related to pain and kind of disassociates [women] from their pain,” said Kelly Curlee, R.N., director of inpatient nursing at Texas Health Cleburne in Cleburne, Tex. “Pain breeds fear, fear breeds pain. That’s kind of a cycle that nitrous helps break.” © 2019 The New York Times Company

Keyword: Pain & Touch
Link ID: 26319 - Posted: 06.10.2019

By John Horgan I can live without God, but I need free will. Without free will life makes no sense, it lacks meaning. So I’m always on the lookout for strong, clear arguments for free will. Christian List, a philosopher at the London School of Economics, provides such arguments in his succinct new book Why Free Will Is Real (Harvard 2019). I met List in 2015 when I decided to attend, after much deliberation, a workshop on consciousness at NYU. I recently freely chose to send him some questions, which he freely chose to answer. –John Horgan Horgan: Why philosophy? Was your choice pre-determined? List: I don’t think it was. As a teenager, I wanted to become a computer scientist or mathematician. It was only during my last couple of years at high school that I developed an interest in philosophy, and then I studied mathematics and philosophy as an undergraduate. For my doctorate, I chose political science, because I wanted to do something more applied, but I ended up working on mathematical models of collective decision-making and their implications for philosophical questions about democracy. Can majority voting produce rational collective outcomes? Are there truths to be found in politics? So, I was drawn back into philosophy. But the fact that I now teach philosophy is due to contingent events, especially meeting some philosophers who encouraged me. Horgan: Free-will denial seems to be on the rise. Why do you think that is? List: The free-will denial we are now seeing appears to be a by-product of the growing popularity of a reductionistic worldview in which everything is thought to be reducible to physical processes. If we look at the world solely through the lens of fundamental physics, for instance, then we will see only particles, fields, and forces, and there seems no room for human agency and free will. People then look like bio-physical machines. My response is that this kind of reductionism is mistaken. I want to embrace a scientific worldview, but reject reductionism. In fact, many scientists reject the sort of reductionism that is often mistakenly associated with science. © 2019 Scientific American

Keyword: Consciousness
Link ID: 26318 - Posted: 06.10.2019

By Lisa Feldman Barrett My husband found me sobbing on the kitchen floor. My job was in upheaval, my travel schedule was grueling, and with two hours left before my next departure, I’d discovered that my laptop was dead. This was the moment my husband walked in to console me, and in an impressive feat of bad timing, he also asked whether I was premenstrual. I went from sobbing to supernova in about two seconds, enraged by his presumption that surging female hormones were responsible for my emotional distress. The only thing that saved him was that, a few days later, I discovered that he’d been right. I am a scientist who studies the nature of emotions. For most of my scientific career, I didn’t believe that women systematically had emotional eruptions right before their period, even though I experienced them occasionally. Studies suggested that women who believe in premenstrual syndrome, when asked about it in retrospect, tend to misremember the symptoms as more severe than they were. The evidence for PMS overall was inconsistent. Certainly, I knew of no neurological reason that women should feel, just before their period, that the world was crashing down on them. My doubt was also political in nature. During my clinical internship over 20 years ago, my boss, a psychiatrist, asked me to research how PMS prevents women from thinking clearly. I told him he was a relic of the Stone Age. Women were as consistently clearheaded as men, if not more so. But recently, a researcher in my lab, Joe Andreano, an expert on female hormones, showed me some surprising data. As a woman’s levels of progesterone and estrogen vary, so does the connectivity between two brain networks: the default mode network and the salience network. These networks play key roles in creating your emotional life. If I hadn’t seen the data with my own eyes, I wouldn’t have believed it. © 2019 The New York Times Company

Keyword: Hormones & Behavior; Sexual Behavior
Link ID: 26317 - Posted: 06.10.2019

Patti Neighmond Jeannine, who is 37 and lives in Burbank, Calif., has endured widespread pain since she was 8. She has been examined by dozens of doctors, but none of their X-rays, MRIs or other tests have turned up any evidence of physical injury or damage. Over the years, desperate for relief, she tried changing her diet, wore belts to correct her posture and exercised to strengthen muscles. Taking lots of ibuprofen helped, she says, but doctors warned her that taking too much could cause gastric bleeding. Nothing else eased her discomfort. On a pain scale of 0 to 10, her pain ranged from "7 to 9, regularly," she says. Around 50 million Americans suffer from chronic pain. Most of us think of pain as something that arises after a physical injury, accident or damage from an illness or its treatment. But researchers are learning that, in some people, there can be another source of chronic pain. Repeated exposure to psychological trauma, or deep anxiety or depression — especially in childhood — can leave a physical imprint on the brain that can make some people, like Jeannine, more vulnerable to chronic pain, scientists say. (We are not using her last name for reasons of privacy.) Jeannine was eventually diagnosed with fibromyalgia — a condition characterized by widespread pain throughout the body, among other symptoms. The cause is unknown and likely varies from person to person. The pain Jeannine experienced was physical. She'd feel "lightning bolts, kind of going up through my shoulders to my neck to my head," she says. Other times, she'd suddenly experience the shooting pain of sciatica in her legs, and she often suffered from a "grinding pain" in her hips. "I would feel like I can't walk anymore — it was just so very painful to walk." © 2019 npr

Keyword: Pain & Touch
Link ID: 26316 - Posted: 06.10.2019

By Jane E. Brody How did you sleep last night? If you’re over 65, I hope it was better than many others your age. In a study by the National Institute on Aging of over 9,000 Americans aged 65 and older, more than half said they had difficulty falling asleep or staying asleep. Many others who believe they spend an adequate number of hours asleep nonetheless complain of not feeling rested when they get up. Chronic insomnia, which affects 5 percent to 10 percent of older adults, is more than just exhausting. It’s also linked to an increased risk of developing hypertension, Type 2 diabetes, heart attack, depression, anxiety and premature death. It may also be a risk factor for dementia, especially Alzheimer’s disease. Studies based on more than 1,700 men and women followed over many years by researchers at Pennsylvania State University College of Medicine found that the risk of developing hypertension was five times greater among those who slept less than five hours a night and three and a half times greater for those who slept between five and six hours. But there was no increased risk among those who regularly slept six or more hours. Likewise, the risk of developing diabetes was three times greater for the shortest sleepers and twice as great for those who slept between five and six hours. People with insomnia often complain that they can’t concentrate or focus and have memory problems. While the evidence for this is inconsistent, the Penn State studies showed that people with insomnia are more likely to perform poorly on tests of processing speed, switching attention and visual memory. And most studies have shown that insomnia impairs cognitive performance, a possible risk factor for mild cognitive impairment and dementia. © 2019 The New York Times Company

Keyword: Sleep; Alzheimers
Link ID: 26315 - Posted: 06.10.2019

Hannah Devlin Science correspondent Smartphone sleep-tracking apps are making people so anxious and obsessed about their sleep that they are developing insomnia, a leading neurologist has said. Speaking at the Cheltenham science festival, Dr Guy Leschziner, a sleep disorder specialist and consultant at Guy’s hospital in London, said a growing preoccupation with getting enough sleep was backfiring. “We’ve seen a lot of people who have developed significant insomnia as a result of either sleep trackers or reading certain things about how devastating sleep deprivation is for you,” Leschziner said before his talk. A high proportion of patients seeking treatment for insomnia turn up at his clinic with data about their sleep patterns and are often reluctant to delete the app, he said. “It’s rather difficult to dissuade them from using it.” Most apps have not been clinically validated and only track movement, so do not provide insight into the quality of sleep, he added. “My view of sleep trackers is fairly cynical. If you wake up feeling tired and you’ve had an unrefreshing night’s sleep then you know you’ve got a problem,” he said. “If you wake up every day and feel refreshed, are awake throughout the day and are ready to sleep at the same time every night then you’re probably getting enough sleep for you and you don’t need an app to tell you that.” Similar concerns were highlighted in a series of case studies published last year by a team in Chicago that described patients whose micromanagement of sleep using apps had led to a disorder called orthosomnia. © 2019 Guardian News & Media Limited

Keyword: Sleep
Link ID: 26314 - Posted: 06.10.2019

By Darcey Steinke The J in “juice” was the first letter-sound, according to my mother, that I repeated in staccato, going off like a skipping record. This was when I was 3, before my stutter was stigmatized as shameful. In those earliest years my relationship to language was uncomplicated: I assumed my voice was more like a bird’s or a squirrel’s than my playmates’. This seemed exciting. I imagined, unlike fluent children, I might be able to converse with wild creatures, I’d learn their secrets, tell them mine and forge friendships based on interspecies intimacy. School put an end to this fantasy. Throughout elementary school I stuttered every time a teacher called on me and whenever I was asked to read out loud. In the third grade the humiliation of being forced to read a few paragraphs about stewardesses in the Weekly Reader still burns. The ST is hard for stutterers. What would have taken a fluent child five minutes took me an excruciating 25. It was around this time that I started separating the alphabet into good letters, V as well as M, and bad letters, S, F and T, plus the terrible vowel sounds, open and mysterious and nearly impossible to wrangle. Each letter had a degree of difficulty that changed depending upon its position in the sentence. Much later when I read that Nabokov as a child assigned colors to letters, it made sense to me that the hard G looked like “vulcanized rubber” and the R, “a sooty rag being ripped.” My beloved V, in the Nabokovian system, was a jewel-like “rose quartz.” My mother, knowing that kids ridiculed me — she once found a book, “The Mystery of the Stuttering Parrot,” that had been tossed onto our lawn — wanted to eradicate my speech impediment. She encouraged me to practice the strategies taught to me by a string of therapists, bouncing off an easy sound to a harder one and unclenching my throat, trying to slide out of a stammer. When I was 13 she got me a scholarship to a famous speech therapy program at a college near our house in Virginia. © 2019 The New York Times Company

Keyword: Language
Link ID: 26313 - Posted: 06.10.2019

By Joshua Sokol For half the year, a little brown bird on the northernmost islands of the Galápagos uses its wickedly sharp beak to pick at seeds, nectar and insects. But when the climate dries out, it drinks blood. Yes, there is such a thing as a vampire finch. Yes, it is what it sounds like. Galápagos finches have been used since Darwin’s time to illustrate evolution in action. Even among them, Geospiza septentrionalis is an outlier, one of the few birds in the world to intentionally draw and drink blood. And the species is only found on Wolf and Darwin islands, two of the most remote and off-limits places in the entire archipelago. The vampire finch has a method. First, one bird hops on the back of a resting Nazca booby, pecks at the base of the seabird’s wing, and drinks. Blood stains the booby’s white feathers. Other finches crowd around to wait their turn, or to watch and learn. Because adult boobies can fly away, the attacks are almost never fatal. The only casualties are chicks that flee from the finches on foot and, unable to find their way back, starve. Drinking blood is an unusual diet, and research published last year showed that vampire finches have evolved specialized bacteria in their guts to aid digestion. Even more surprising, according to a paper this week in the journal Philosophical Transactions of the Royal Society B, is that some of these bacteria are similar to ones found in the vampire bats of Central and South America. Se Jin Song, a biologist at the University of California San Diego and the study’s lead author, had previously studied the convergent evolution of gut bacteria. Do disparate animals with the equivalent of fad diets — eating only ants and termites, for instance — develop similar gut microbiota over evolutionary time? © 2019 The New York Times Company

Keyword: Evolution; Obesity
Link ID: 26312 - Posted: 06.10.2019