By Jack Turban We all know that person. Her Instagram is covered with more pictures of feline friends than human companions. Not an insignificant number of these pictures feature mini cat-sized lattes with the caption “Fluffy simply adores her morning coffee.” And let us not forget that the archetype of crazy cat man may be just as prevalent. When you look at these pictures, you probably wonder: is he like this because of the cat? Or does he have the cat because he is like this? It turns out that cats have a mischievous and somewhat dark reputation in neuroscience. There is research to suggest that a cat’s proximity to other mammals can cause them to behave strangely. This feline power has been attributed to a protozoan that lives in their stool, called Toxoplasma gondii (or Toxo for short). In one classic story, researchers showed that Toxo can travel into a rat’s brain and cause the rat to no longer avoid areas where cats live. The rats, in fact, become attracted to the smell of cat urine. Previously repulsed by the smell, these brain-infected rodents run joyously through urine-laden environments. They walk right through the cat’s trap, until their young rodent lives come to an end under a forceful paw. These same protozoans can affect the brains of humans. Immuno-compromised patients, like those with AIDS, can contract the infection from a litter box and develop dangerous brain abscesses. We treat these patients with powerful antibiotics and frequently recommend that they give away their cats. Pregnant women are also advised not to handle cat litter, as a fetus does not yet have the immune system needed to fight Toxo. Fetuses exposed to the protozoan can suffer from seizures, cognitive problems, and blindness. But what about your immunocompetent and decidedly non-pregnant Instagram friend; is she under the influence of this cat’s protozoan minion? . © 2017 Scientific American,

Keyword: Emotions
Link ID: 23651 - Posted: 05.24.2017

Carl Zimmer In a significant advance in the study of mental ability, a team of European and American scientists announced on Monday that they had identified 52 genes linked to intelligence in nearly 80,000 people. These genes do not determine intelligence, however. Their combined influence is minuscule, the researchers said, suggesting that thousands more are likely to be involved and still await discovery. Just as important, intelligence is profoundly shaped by the environment. Still, the findings could make it possible to begin new experiments into the biological basis of reasoning and problem-solving, experts said. They could even help researchers determine which interventions would be most effective for children struggling to learn. “This represents an enormous success,” said Paige Harden, a psychologist at the University of Texas, who was not involved in the study. For over a century, psychologists have studied intelligence by asking people questions. Their exams have evolved into batteries of tests, each probing a different mental ability, such as verbal reasoning or memorization. In a typical test, the tasks might include imagining an object rotating, picking out a shape to complete a figure, and then pressing a button as fast as possible whenever a particular type of word appears. Each test-taker may get varying scores for different abilities. But over all, these scores tend to hang together — people who score low on one measure tend to score low on the others, and vice versa. Psychologists sometimes refer to this similarity as general intelligence. It’s still not clear what in the brain accounts for intelligence. Neuroscientists have compared the brains of people with high and low test scores for clues, and they’ve found a few. Brain size explains a small part of the variation, for example, although there are plenty of people with small brains who score higher than others with bigger brains. © 2017 The New York Times Company

Keyword: Intelligence; Genes & Behavior
Link ID: 23650 - Posted: 05.23.2017

Nicola Davis Air pollution might be linked to poor sleep, say researchers looking into the impact of toxic air on our slumbers. The study explored the proportion of time participants spent asleep in bed at night compared with being awake – a measure known as sleep efficiency. The results reveal that greater exposure to nitrogen dioxide and small particulates known as PM 2.5s are linked with a greater chance of having low sleep efficiency. That, researchers say, could be down to the impact of air pollution on the body. “Your nose, your sinuses and the back of your throat can all be irritated by those pollutants so that can cause some sleep disruption as well as from breathing issues,” said Martha Billings, assistant professor of medicine at the University of Washington and co-author of the research. Billings added that pollutants entering the blood could have an effect on the brain and hence the regulation of breathing. The study, presented at the American Thoracic Society’s annual international conference, drew on air pollution data captured for nitrogen dioxide and PM2.5 levels over a five-year period in six US cities, including data captured near the homes of the 1,863 participants. The data was then used to provide estimates of pollution levels in the home. Researchers then captured data from medical-grade wearable devices worn by the participants on their wrists over a period of seven consecutive days to monitor fine movements while they slept – an approach that offers insights into how long each participant spent asleep or awake.

Keyword: Sleep; Neurotoxins
Link ID: 23649 - Posted: 05.23.2017

By PERRI KLASS, M.D. Why do children wake up early when they are young but want to stay in bed till noon as teenagers? Experts say it’s biology. Adolescents’ bodies want to stay up late and sleep late, putting them out of sync with what their school schedules demand of them. So kids have trouble waking up, and they often find themselves feeling drowsy in morning algebra class. But that chronic sleepiness can affect their health and well-being, their behavior, and even their safety; it becomes genuinely dangerous when sleepy teenagers get behind the wheel. At a recent conference on adolescent sleep, health and school start times, at which I gave a brief keynote, several experts made compelling arguments supporting the idea that middle and high school start times should shift to 8:30 a.m. or later, as recommended by the American Academy of Pediatrics and the American Academy of Sleep Medicine. Brian Tefft, a senior researcher with the AAA Foundation for Traffic Safety, talked about “drowsy driving.” He cited an annual study that asks, “In the past 30 days how often have you driven when you were so tired that you had a hard time keeping your eyes open?” Over the past five years, on average, a quarter of the 16- to 18-year-old licensed drivers reported driving in that condition at least once, and 2 percent said fairly often or regularly. The argument is that teenagers who face very early school start times are at risk of regular sleep deprivation. Driving after sleeping only four to five hours a night is associated with a similar crash risk as driving with an alcohol level at the legal limit. Sleeping less than four hours puts you at the same risk as driving with double the legal alcohol limit. (This is not only true for adolescents, but for all of us.) Drowsy driving may not be the only risk that tired teenagers take. Wendy Troxel, a clinical psychologist and senior behavioral and social scientist at RAND, talked about the “adolescent health paradox,” that teenagers, who are in a developmental period of physical strength and resilience, face disproportionately high mortality rates. Unintentional injury (especially car crashes) is high on the list of causes, followed by homicide and suicide. © 2017 The New York Times Company

Keyword: Sleep; Development of the Brain
Link ID: 23648 - Posted: 05.23.2017

Claude Messier, Alexandria Béland-Millar, The short answer is yes: certain brain regions do indeed consume more energy when engaged in particular tasks. Yet the specific regions involved and the amount of energy each consumes depend on the person’s experiences as well as each brain’s individual properties. Before we delve into the answer, it is important to understand how we measure a brain’s energy expenditure. Picture the colorful brain images researchers use to display neural activity. The colors typically represent the amount of oxygen or glucose various brain regions use during a task. Our brain is always active on some level—even when we are not engaged in a task—but it requires more energy to accomplish something that demands concentration such as moving, seeing or thinking. A simple example is that our primary visual cortex lights up more in brain scans—consuming more energy—when our eyes are open than when they are closed. Similarly, our primary motor cortex uses more energy if we move our hands than if we keep them still. Say you are learning a new skill—how to juggle or speak Spanish. Neuroscientists have made the fascinating observation that when we do something completely novel, a broad range of brain areas becomes active. As we become more skilled at the task, however, our brain becomes more focused: we require only the essential brain regions and need increasingly less energy to perform that task. Once we have mastered a skill—we become fluent in Spanish—only the brain areas directly involved remain active. Thus, learning a new skill requires more brainpower than a well-practiced activity. © 2017 Scientific American

Keyword: Brain imaging
Link ID: 23647 - Posted: 05.23.2017

By GRETCHEN REYNOLDS Mice do not, so far as we know, practice meditation. But in order to study how that activity affects human brains at the cellular level, researchers at the University of Oregon managed to put murine brains into a somewhat equivalent state. Their experiments, reported in March in the Proceedings of the National Academy of Sciences, suggest new ways of investigating how a person’s brain can constantly reshape itself. Past studies have suggested that people who meditate tend to have more white matter in and around the anterior cingulate cortex, a part of the brain involved in regulating emotions. Meditation also seems to intensify theta-wave activity, a type of rhythmic electrical pulsation often associated with a state of calm. Psychologists at Oregon speculated that the surge in theta waves stimulated the production of cells in the white matter. But they needed to develop an animal model of this activity; they obviously couldn’t examine the living brain tissue in meditating humans. So the psychologists asked colleagues in the university’s neuroscience department if they could increase theta-wave activity in mice, which were already being used to study brain states and neural plasticity, or the brain’s ability to rewire itself. Could the neuroscientists create a comparable effect in mice? Yes, it turned out, using a brain-research technique known as optogenetics, which uses light to turn on and off neurons, and mice that have been bred with specific genes responsive to light. The Oregon group, by pulsing the light at the same frequency found in human theta waves (eight hertz), were able to switch on the neurons in the anterior cingulate cortexes of the mice. They also exposed some mice to light at higher and lower frequencies and left others alone. Each treated mouse received 30 minutes of light therapy for 20 days, in an attempt to mimic the amount of meditation done in earlier human studies. Afterward, those mice exposed to the eight-hertz, thetalike light waves proved to be relatively calm in behavioral tests: they lingered in lighted portions of a special cage, while their twitchier counterparts ran for the shadows. © 2017 The New York Times Company

Keyword: Stress
Link ID: 23646 - Posted: 05.22.2017

By Catherine Caruso If you give a mouse a beer, he is going to want a cookie—and another, and another. If you give a person enough beer, she might find herself wolfing down a plate of greasy nachos or some other caloric snack. A study published in January in Nature Communications helps to explain why binge drinking, in both mice and humans, so often leads to binge eating even though alcohol is, itself, high in calories. In the first part of the study, neuroscientists Craig Blomeley and Sarah Cains, both at the Francis Crick Institute Mill Hill Laboratory in London, injected mice with the equivalent of roughly two bottles of wine once a day for three consecutive days, mimicking a weekend of heavy drinking. Sure enough, the inebriated mice ate far more than sober mice in a control group. To figure out why, the researchers then exposed thin-sliced postmortem mouse brains to alcohol and measured the resulting neural activity using fluorescent tags and electrodes. They found that ethanol exposure alters calcium exchange in the cells, causing specialized nerve cells called agouti-related protein (AgRP) neurons to fire more frequently and easily. These neurons normally fire when our body needs calories, and research has shown that activating them artificially will cause mice to chow down even when they are full. The study results suggest that alcohol activates AgRP neurons in the brain, giving drunk mice the munchies. The same is likely true for humans because this brain circuitry has been highly conserved across mammal species, Cains says: “I don't doubt that AgRP neurons are activated in humans, and that's why you see this effect.” © 2017 Scientific American

Keyword: Drug Abuse; Obesity
Link ID: 23645 - Posted: 05.22.2017

By LISA SANDERS, M.D. The woman woke to the sound of her 57-year-old husband sobbing. They’d been married for 30 years, and she had never heard him cry before. “I hurt so much,” he wailed. “I have to go back to the hospital.” The symptoms started two weeks earlier. One afternoon, coming home from his job as a carpenter, he felt hot and tired. He shook with shivers even though the day was warm. He drank a cup of tea and went to bed. The next day he felt fine, until the end of the day, when he felt overwhelmed by the heat and chills again. The day after that was the same. When he woke one morning and saw that his body was covered with pale pink dots — his arms, his face, his chest and thighs — he started to worry. His wife took him to the Griffin Hospital emergency room in Derby, Conn. The first doctor who saw him thought he probably had Lyme disease. Summer had just started, and he’d already seen a lot of cases. He sent the patient home with an antibiotic and steroid pills for the rash. The man took the medications but didn’t get any better. Soon everything started to hurt. His muscles, his joints and his back felt as if he’d been beaten. He dragged himself back to the E.R. He was given pain pills. A few days later, he went to the E.R. a third time and was given more pain meds. After waking up crying, he went yet again, and this time, the doctors admitted him. By then the patient had had several blood tests, which showed no sign of Lyme or other tick-borne diseases. A CT scan was equally uninformative. The next day, the man was walking to the bathroom when his legs gave out and he fell down. The doctor in charge of his care came and examined him once again. The man looked fit and healthy, despite the now-bright-red rash, but his legs were extremely weak. If the doctor applied even light pressure to the raised leg, it sagged back down to the bed. And his feet felt numb. He had a sensation of tingling in his hands, as if they had gone to sleep. That was how the weakness and numbness in his legs started, he told the doctor. And the next day, his hands were so weak he had to use both just to drink a cup of water. © 2017 The New York Times Company

Keyword: Movement Disorders; Neuroimmunology
Link ID: 23644 - Posted: 05.22.2017

Jon Hamilton It took an explosion and 13 pounds of iron to usher in the modern era of neuroscience. In 1848, a 25-year-old railroad worker named Phineas Gage was blowing up rocks to clear the way for a new rail line in Cavendish, Vt. He would drill a hole, place an explosive charge, then pack in sand using a 13-pound metal bar known as a tamping iron. But in this instance, the metal bar created a spark that touched off the charge. That, in turn, "drove this tamping iron up and out of the hole, through his left cheek, behind his eye socket, and out of the top of his head," says Jack Van Horn, an associate professor of neurology at the Keck School of Medicine at the University of Southern California. Gage didn't die. But the tamping iron destroyed much of his brain's left frontal lobe, and Gage's once even-tempered personality changed dramatically. "He is fitful, irreverent, indulging at times in the grossest profanity, which was not previously his custom," wrote John Martyn Harlow, the physician who treated Gage after the accident. This sudden personality transformation is why Gage shows up in so many medical textbooks, says Malcolm Macmillan, an honorary professor at the Melbourne School of Psychological Sciences and the author of An Odd Kind of Fame: Stories of Phineas Gage. "He was the first case where you could say fairly definitely that injury to the brain produced some kind of change in personality," Macmillan says. © 2017 npr

Keyword: Attention; Emotions
Link ID: 23643 - Posted: 05.22.2017

Elle Hunt About 150 years ago, and “almost a lifetime” either side, Charles Darwin was beleaguered by the problem of the peacock’s tail. Just the sight of a feather, he wrote in April 1860, “makes me sick!” The plumage of the male bird represented a hole in his theory of evolution. According to Victorian thinking, beauty was divine creation: God had designed the peacock for his own and humankind’s delight. In, On The Origin of Species, published the previous year, Darwin had challenged the dominant theory of creationism, arguing that man had been made not in God’s image but as a result of evolution, with new species formed over generations in response to their environment. But beauty, and a supposed aesthetic sense in animals (“We must suppose [that peahens] admire [the] peacock’s tail, as much as we do,” he wrote), took Darwin the best part of his life to justify – not least because the theory he eventually landed upon went against the grain of his entire worldview. Sexual selection was of strategic importance to Darwin, says Evelleen Richards, an honorary professor in history and philosophy of science at the University of Sydney: it was a naturalistic account for aesthetic differences between male and female animals of the same species, shoring up his defence of natural selection.

Keyword: Evolution; Sexual Behavior
Link ID: 23642 - Posted: 05.22.2017

By MARTIN E. P. SELIGMAN and JOHN TIERNEY We are misnamed. We call ourselves Homo sapiens, the “wise man,” but that’s more of a boast than a description. What makes us wise? What sets us apart from other animals? Various answers have been proposed — language, tools, cooperation, culture, tasting bad to predators — but none is unique to humans. What best distinguishes our species is an ability that scientists are just beginning to appreciate: We contemplate the future. Our singular foresight created civilization and sustains society. It usually lifts our spirits, but it’s also the source of most depression and anxiety, whether we’re evaluating our own lives or worrying about the nation. Other animals have springtime rituals for educating the young, but only we subject them to “commencement” speeches grandly informing them that today is the first day of the rest of their lives. A more apt name for our species would be Homo prospectus, because we thrive by considering our prospects. The power of prospection is what makes us wise. Looking into the future, consciously and unconsciously, is a central function of our large brain, as psychologists and neuroscientists have discovered — rather belatedly, because for the past century most researchers have assumed that we’re prisoners of the past and the present. Behaviorists thought of animal learning as the ingraining of habit by repetition. Psychoanalysts believed that treating patients was a matter of unearthing and confronting the past. Even when cognitive psychology emerged, it focused on the past and present — on memory and perception. But it is increasingly clear that the mind is mainly drawn to the future, not driven by the past. Behavior, memory and perception can’t be understood without appreciating the central role of prospection. We learn not by storing static records but by continually retouching memories and imagining future possibilities. Our brain sees the world not by processing every pixel in a scene but by focusing on the unexpected. © 2017 The New York Times Company

Keyword: Attention; Learning & Memory
Link ID: 23641 - Posted: 05.20.2017

By Clare Wilson Seeing shouldn’t always be believing. We all have blind spots in our vision, but we don’t notice them because our brains fill the gaps with made-up information. Now subtle tests show that we trust this “fake vision” more than the real thing. If the brain works like this in other ways, it suggests we should be less trusting of the evidence from our senses, says Christoph Teufel of Cardiff University, who wasn’t involved in the study. “Perception is not providing us with a [true] representation of the world,” he says. “It is contaminated by what we already know.” The blind spot is caused by a patch at the back of each eye where there are no light-sensitive cells, just a gap where neurons exit the eye on their way to the brain. We normally don’t notice blind spots because our two eyes can fill in for each other. When vision is obscured in one eye, the brain makes up what’s in the missing area by assuming that whatever is in the regions around the spot continues inwards. But do we subconsciously know that this filled-in vision is less trustworthy than real visual information? Benedikt Ehinger of the University of Osnabrück in Germany and his colleagues set out to answer this question by asking 100 people to look at a picture of a circle of vertical stripes, which contained a small patch of horizontal stripes. The circle was positioned so that with one eye obscured, the patch of horizontal stripes fell within the other eye’s blind spot. As a result, the circle appeared as though there was no patch and the vertical stripes were continuous. © Copyright New Scientist Ltd.

Keyword: Vision; Attention
Link ID: 23640 - Posted: 05.20.2017

Sarah Boseley in Porto A crinkly plate, designed with ridges that cunningly reduce the amount of food it holds, may be heading for the market to help people concerned about their weight to eat less. The plate is the brainchild of a Latvian graphic designer, Nauris Cinovics, from the Art Academy of Latvia, who is working with a Latvian government agency to develop the idea and hopes to trial it soon. It may look like just another arty designer plate, but it is intended to play tricks with the mind. “My idea is to make food appear bigger than it is. If you make the plate three-dimensional [with the ridges and troughs] it actually looks like there is the same amount of food as on a normal plate – but there is less of it,” said Cinovics. “You are tricking the brain into thinking you are eating more.” The plate will be made of clear glass and could turn eating dinner into a more complex and longer process than it is usually for most of us. Negotiating the folds in the glass where pieces of fish or stray carrots may lurk will slow down the speed with which people get through their meal. Cinovics has also designed heavy cutlery, with the idea of making eating more of a labour – that therefore lasts longer. His knife, fork and spoon weigh 1.3kg each. “We tested this and it took 11 minutes to finish a meal with this cutlery rather than seven minutes,” he said.

Keyword: Obesity; Attention
Link ID: 23639 - Posted: 05.20.2017

Laura Beil Even though a sprained ankle rarely needs an opioid, a new study of emergency room patients found that about 7 percent of patients got sent home with a prescription for the potentially addictive painkiller anyway. And the more pills prescribed, the greater the chance the prescription would be refilled, raising concerns about continued use. The research adds to evidence that it’s hard for some people to stop taking the pills even after a brief use. State officials in New Jersey recently enacted a law limiting first-time prescriptions to a five-day supply, and other states should consider similar restrictions, says Kit Delgado, an assistant professor of Emergency Medicine and Epidemiology at the University of Pennsylvania. “The bottom line is that we need to do our best not to expose people to opioids,” Delgado says. “And if we do, start with the smallest quantity possible.” The research was presented May 17 at the Society for Academic Emergency Medicine’s annual meeting in Orlando. Previous research has found that the more opioids such as hydrocodone and oxycodone are prescribed, the more likely patients are to keep taking them. But previous studies have been too broad to account for differences in diagnoses — for instance, whether people who received refills kept taking the drug simply because they still were in pain, Delgado says. He and colleagues limited their study to prescriptions written after ankle sprains to people who had not used an opioid in the previous six months. Usually, those injuries aren’t serious and don’t require opioids. |© Society for Science & the Public 2000 - 2017

Keyword: Drug Abuse; Pain & Touch
Link ID: 23638 - Posted: 05.20.2017

By Bret Stetka For many hours a day they pluck dirt, debris and bugs from each other’s fur. Between grooming sessions they travel in troops to search for food. When ignored by mom, they throw tantrums; when not ignored by zoo-goers, they throw feces. Through these behaviors, monkeys demonstrate they understand the meaning of social interactions with other monkeys. They recognize when their peers are grooming one another and infer social rank from seeing such actions within their group. But it has long been unclear how the brains of our close evolutionary relatives actually process what they observe of these social situations. New findings published Thursday in Science offer a clue. A team of researchers from The Rockefeller University have identified a network in the monkey brain dedicated exclusively to analyzing social interactions. And they believe this network could be akin to human brains’ social circuitry. In the new work—led by Winrich Freiwald, an associate professor of neurosciences and behavior—four rhesus macaques viewed videos of various social and physical interactions while undergoing functional magnetic resonance imaging. (Monkeys love watching TV, so they paid attention.) They were shown clips of monkeys interacting, as well as performing tasks on their own. They also watched videos of various physical interactions among inanimate objects. © 2017 Scientific American

Keyword: Attention; Evolution
Link ID: 23637 - Posted: 05.19.2017

By: Ted Dinan, M.D., Ph.D, and John F. Cryan, Ph.D. O ver the past few years, the gut microbiota has been implicated in developmental disorders such as schizophrenia and autism, neurodegenerative disorders such as Alzheimer’s disease and Parkinson’s disease, mood disorders such as depression, and even addiction disorders. It now seems strange that for so many decades we viewed the gut microbiota as bacteria that did us no harm but were of little benefit. This erroneous view has been radically transformed into the belief that the gut microbiota is, in effect, a virtual organ of immense importance. What we’ve learned is that what is commonly referred to as “the brain-gut-microbiota axis” is a bidirectional system that enables gut microbes to communicate with the brain and the brain to communicate back to the gut. It may be hard to believe that the microbes in the gut collectively weigh around three pounds—the approximate weight of the adult human brain—and contain ten times the number of cells in our bodies and over 100 times as many genes as our genome. 1 If the essential microbial genes were to be incorporated into our genomes, it is likely that our cells would not be large enough for the extra DNA. Many of those genes in our microbiota are important for brain development and function; they enable gut bacteria to synthesize numerous neurotransmitters and neuromodulators such as γ-aminobutyric acid (GABA), serotonin, dopamine, and short-chain fatty acids. While some of these compounds act locally in the gut, many products of the microbiota are transported widely and are necessary for the proper functioning of diverse organs. This is a two-way interaction: gut microbes are dependent on us for their nourishment. Any pathological process that reduces or increases food intake has implications for our microbes. © 2017 The Dana Foundation. All Rights Reserved.

Keyword: Parkinsons
Link ID: 23636 - Posted: 05.19.2017

By Esther Landhuis On the heels of one failed drug trial after another, a recent study suggests people with early Alzheimer’s disease could reap modest benefits from a device that uses magnetic fields to produce small electric currents in the brain. Alzheimer’s is a degenerative brain disorder that afflicts more than 46 million people worldwide. At present there are no treatments that stop or slow its progression, although several approved drugs offer temporary relief from memory loss and other cognitive symptoms by preventing the breakdown of chemical messengers among nerve cells. The new study tested a regimen that combines computerized cognitive training with a procedure known as repetitive transcranial magnetic stimulation (rTMS). The U.S. Food and Drug Administration has cleared rTMS devices for some migraine sufferers as well as for people with depression who have not responded to antidepressant medications. Last month at the 13th International Conference on Alzheimer’s and Parkinson’s Diseases in Vienna, Israel-based Neuronix reported results of a phase III clinical trial of its therapy system, known as neuroAD, in Alzheimer’s patients. More than 99 percent of Alzheimer’s drug trials have failed. The last time a phase III trial for a wholly new treatment succeeded (not just a combination of two already approved drugs) was about 15 years ago. The recent study did not test a drug but rather a device, which usually has an easier time gaining FDA clearance. NeuroAD has been approved for use in Europe and the U.K., where six weeks of therapy costs about $6,700. The system is not commercially available in the U.S., but based on the latest results the company submitted an application for FDA clearance last fall. © 2017 Scientific American

Keyword: Alzheimers
Link ID: 23635 - Posted: 05.19.2017

By RONI CARYN RABIN Q. How can a blood test determine if I have prediabetes? How much weight do I need to lose to bring my numbers down? A. Doctors typically perform one of three blood tests to diagnose prediabetes, a condition marked by blood sugar (glucose) levels that are higher than normal but not high enough to qualify as diabetes. While prediabetes often leads to full-fledged Type 2 diabetes, many people can hold the condition in check if they lose a relatively small amount of weight and increase their physical activity, said Dr. Rhonda Bentley-Lewis, an assistant professor of medicine at Harvard Medical School. “I stress to my patients that we’re not talking about a huge amount of weight,” she said, “just 5 to 7 percent of one’s body weight” — or 10 to 14 pounds for someone who weighs 200 pounds. Two of the tests require fasting, which helps prevent results being distorted by a prior meal and provides “an even baseline,” Dr. Bentley-Lewis said. One, the fasting plasma glucose test, checks blood glucose levels after an 8 to 10 hour fast; results of 100 to 125 milligrams per deciliter indicate prediabetes. The other, the oral glucose tolerance test, is the most sensitive. It checks blood glucose levels after fasting and then two hours after you consume a sweetened drink; levels of 140 to 199 after the drink indicate prediabetes. A third test, the A1C test, may be the most convenient because it doesn’t require fasting. It measures your average blood glucose levels over the past two to three months; results of 5.7 percent to 6.4 percent, which indicate the percentage of red blood cells that have glucose attached to them, indicate prediabetes. Though doctors often repeat a test to confirm a diabetes diagnosis, they do not always do so for a prediabetes diagnosis, Dr. Bentley-Lewis said. Doctors can treat prediabetes with medication, but many patients prefer to try weight loss and exercise first, Dr. Bentley-Lewis said. Among thousands of people with prediabetes who participated in a national study called the Diabetes Prevention Program, 58 percent of those who adopted lifestyle changes, like losing a modest amount of weight, stepping up physical activity and reducing the amount of fat and calories in their diets, were able to prevent progression to full-blown diabetes. © 2017 The New York Times Company

Keyword: Obesity
Link ID: 23634 - Posted: 05.19.2017

By GRETCHEN REYNOLDS When young athletes sustain concussions, they are typically told to rest until all symptoms disappear. That means no physical activity, reading, screen time, or friends, and little light exposure, for multiple days and, in severe cases, weeks. Restricting all forms of activity after a concussion is known as “cocooning.” But now new guidelines, written by an international panel of concussion experts and published this month in the British Journal of Sports Medicine, question that practice. Instead of cocooning, the new guidelines suggest that most young athletes should be encouraged to start being physically active with a day or two after the injury. “The brain benefits from movement and exercise, including after a concussion,” says Dr. John Leddy, a professor of orthopedics at the Jacobs School of Medicine and Biomedical Sciences at the University at Buffalo, and one of the co-authors of the new guidelines. There has long been controversy, of course, about the best ways to identify and treat sports-related concussions. Twenty years ago, athletes who banged their heads during play were allowed to remain in the practice or game, even if they stumbled, seemed disoriented, or were “seeing stars.” Little was known then about any possible immediate or long-term consequences from head trauma during sports or about the best responses on the sidelines and afterward. Since then, mounting evidence has indicated that sports-related concussions are not benign and require appropriate treatment. The question has been what these appropriate treatments should be. In the early 2000s, dozens of the world’s premier experts on sports-related concussions started meeting to review studies about concussions, with plans to issue a consensus set of guidelines on how best to identify and deal with the condition. © 2017 The New York Times Company

Keyword: Brain Injury/Concussion
Link ID: 23633 - Posted: 05.18.2017

Susan Milius The supermoms of the mammal world are big, shy redheads. Studying growth layers in orangutan teeth shows that mothers can nurse their youngsters for eight-plus years, a record for wild mammals. Teeth from a museum specimen of a young Bornean orangutan (Pongo pygmaeus) don’t show signs of weaning until 8.1 years of age. And a Sumatran orangutan (P. abelii) was still nursing during the few months before it was killed at 8.8 years, researchers report May 17 in Science Advances. Tests also show that youngsters periodically start to taper off their dependence on their mother’s milk and then, perhaps if solid food grows scarce, go back to what looks like an all-mom diet. Such on-again, off-again nursing cycles aren’t known in other wild mammals, says study coauthor Tanya Smith, an evolutionary anthropologist at Griffith University in Nathan, Australia. Marks of milk drinking Two images of a cross section of a first molar from a 4.5-year-old Bornean orangutan are shown. At left, numbers indicate days from birth (dotted line, starting with 0) when particular spots formed. At right, colors indicate concentrations of barium, which increase (shading toward red) when the youngster depended more on mother’s milk. A greenish swath at the top indicates nursing as an infant that gave way to blue as solid food became part of the diet. Yellow and red streaks indicate repeated times when the youngster again depended mostly on milk for nutrition. oragutan molar |© Society for Science & the Public 2000 - 2017.

Keyword: Sexual Behavior; Development of the Brain
Link ID: 23632 - Posted: 05.18.2017