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

Lesley McClurg When her youngest daughter, Naomi, was in middle school, Ellen watched the teen disappear behind a screen. Her once bubbly daughter went from hanging out with a few close friends after school to isolating herself in her room for hours at a time. (NPR has agreed to use only the pair's middle names, to protect the teen's medical privacy.) "She started just lying there, not moving and just being on the phone," says Ellen. "I was at a loss about what to do." Ellen didn't realize it then, but her daughter was sinking into a pattern of behavior that some psychiatrists recognize from their patients who abuse drugs or alcohol. It's a problem, they say, that's akin to an eating disorder or gambling disorder – some consider it a kind of internet addiction. Estimates of how many people are affected vary widely, researchers say, and the problem isn't restricted to kids and teens, though some – especially those who have depression or anxiety disorder — may be particularly vulnerable. Naomi had always been kind of a nerd — a straight-A student who also sang in a competitive choir. But she desperately wanted to be popular, and the cool kids talked a lot about their latest YouTube favorites. "I started trying to watch as many videos as I could so, like, I knew as much as they did," says Naomi. "The second I got out of school, I was checking my phone." That's not unusual behavior for many teens and adults these days. © 2017 npr

Keyword: Drug Abuse
Link ID: 23631 - Posted: 05.18.2017

Katherine Isbister The fidget spinner craze has been sweeping elementary and middle schools. As of May 17 every one of the top 10 best-selling toys on Amazon was a form of the hand-held toy people can spin and do tricks with. Kids and parents are even making them for themselves using 3D printers and other more homespun crafting techniques. But some teachers are banning them from classrooms. And experts challenge the idea that spinners are good for conditions like ADHD and anxiety. Meanwhile, the Kickstarter online fundraising campaign for the Fidget Cube – another popular fidget toy in 2017 – raised an astounding US$6.4 million, and can be seen on the desks of hipsters and techies across the globe. My research group has taken a deep look at how people use fidget items over the last several years. What we found tells us that these items are not a fad that will soon disappear. Despite sometimes being an annoying distraction for others, fidget items can have some practical uses for adults; our inquiry into their usefulness for children is underway. Fidgeting didn’t start with the spinner craze. If you’ve ever clicked a ballpoint pen again and again, you’ve used a fidget item. As part of our work, we’ve asked people what items they like to fidget with and how and when they use them. (We’re compiling their answers online and welcome additional contributions.) © 2010–2017, The Conversation US, Inc.

Keyword: ADHD; Attention
Link ID: 23630 - Posted: 05.18.2017

Sarah Boseley in Porto A balloon that can be swallowed and then filled with water while in the stomach can help obese people to lose large amounts of weight without invasive surgery, a new study has shown. Bariatric surgery to reduce the size of the stomach is highly effective, but anaesthesia for somebody who is very overweight can be risky. Those who want to undergo the surgery must also undergo a long period of preparation to ready them physically and psychologically. It is expensive, and there is a long waiting list in the UK, even though NHS guidance recommends it be considered. The balloon is swallowed like a pill, but with a long thin tube attached. Ultrasound is used to determine when the balloon is in place in the stomach, and it is then filled with water through the tube. The tube then detaches and is pulled back up the throat and out. Unlike gastric surgery, the balloon is a temporary measure. After 16 weeks, it bursts in the stomach, the water is released and the balloon itself is excreted. A small study presented at the European Congress on Obesity in Porto, Portugal, showed that the 38 patients enrolled in the trial had lost a mean 15.2kg (33.5 lbs) by the end of the 16 weeks, which amounted to about a third (mean 31%) of their excess weight.

Keyword: Obesity
Link ID: 23629 - Posted: 05.18.2017

Tina Hesman Saey Face-to-face, a human and a chimpanzee are easy to tell apart. The two species share a common primate ancestor, but over millions of years, their characteristics have morphed into easily distinguishable features. Chimps developed prominent brow ridges, flat noses, low-crowned heads and protruding muzzles. Human noses jut from relatively flat faces under high-domed crowns. Those facial features diverged with the help of genetic parasites, mobile bits of genetic material that insert themselves into their hosts’ DNA. These parasites go by many names, including “jumping genes,” “transposable elements” and “transposons.” Some are relics of former viruses assimilated into a host’s genome, or genetic instruction book. Others are self-perpetuating pieces of genetic material whose origins are shrouded in the mists of time. “Transposable elements have been with us since the beginning of evolution. Bacteria have transposable elements,” says evolutionary biologist Josefa González. She doesn’t think of transposons as foreign DNA. They are parts of our genomes — like genes. “You cannot understand the genome without understanding what transposable elements are doing,” says González, of the Institute of Evolutionary Biology in Barcelona. She studies how jumping genes have influenced fruit fly evolution. Genomes of most organisms are littered with the carcasses of transposons, says Cédric Feschotte, an evolutionary geneticist at the University of Utah in Salt Lake City. Fossils of the DNA parasites build up like the remains of ancient algae that formed the white cliffs of Dover. One strain of maize, the organism in which Nobel laureate Barbara McClintock first discovered transposable elements in the 1940s, is nearly 85 percent transposable elements (SN: 12/19/09, p. 9). Corn is an extreme example, but humans have plenty, too: Transposable elements make up nearly half of the human genome. |© Society for Science & the Public 2000 - 2017

Keyword: Development of the Brain; Genes & Behavior
Link ID: 23627 - Posted: 05.17.2017

By DAVE PHILIPPS Three-fifths of troops discharged from the military for misconduct in recent years had a diagnosis of post-traumatic stress disorder, traumatic brain injury or another associated condition, according to a report released Tuesday by the Government Accountability Office. The report, mandated by Congress, for the first time combined military medical and staffing data, as well as data from the Department of Veterans Affairs, to show that tens of thousands of wounded troops were kicked out of the armed forces and severed from benefits designed to ease their transition from service in war. “It is everything many of us believed for years” said Kristopher Goldsmith, a veteran who served in Iraq and was discharged for misconduct after a suicide attempt. He is now an assistant director for policy at Vietnam Veterans of America, a veterans advocacy group based in Washington. “Many people didn’t believe that the problem could be this big. Now I hope Congress will direct the resources to making it right.” From 2011 to 2015, according to the report, nearly 92,000 troops were discharged for misconduct — the military equivalent of being fired. Troops can be discharged for reasons like testing positive for drugs or repeatedly showing up late. And in recent years, as the military was downsized, misconduct discharges surged. Of those discharged, 57,000 had a diagnosis of PTSD, traumatic brain injury (known as T.B.I.) or a related condition. About 9,000 were found to have PTSD or T.B.I. But a majority had a personality disorder or an adjustment disorder — diagnoses that count as pre-existing conditions, not war wounds. Critics of the military’s handling of mental health have long accused the military of using such diagnoses to sidestep safeguards put in place for troops with PTSD. © 2017 The New York Times Company

Keyword: Brain Injury/Concussion; Stress
Link ID: 23626 - Posted: 05.17.2017

By Roman Liepelt and Jack Brooks An amputee struggles to use his new prosthetic limb. A patient with a frontal-lobe brain lesion insists that her left hand has a mind of its own. The alleged criminal claims in court that he did not fire the gun, even though several eyewitnesses watched him do it. Each of these individuals is grappling with two elements of the mind-body connection: ownership, or an ability to separate ourselves from the physical and social environments, and agency, a conviction that we have control over our limbs. We are quick to investigate a sticker placed on our forehead when looking in a mirror, recognizing the foreign object as abnormal. The human brain typically handles these phenomena by comparing neural signals encoding the intended action with those signals carrying sensory feedback. When we are born, we make erratic reaching and kicking movements to map our body and to calibrate our sensorimotor system. During infancy, these movements solidify our self-awareness, and around the time we first walk, we are quick to investigate a sticker placed on our forehead when looking in a mirror, recognizing the foreign object as abnormal. By the age of four, our brains are proficient at distinguishing self and other. In the amputee, the brain lesion patient, and the defendant on trial, the sense of self is disrupted due to discordance between sensory feedback from the limb and the brain’s expectations of how a movement should feel. © 1986-2017 The Scientist

Keyword: Pain & Touch
Link ID: 23625 - Posted: 05.17.2017

Shelly Fan The first time I heard that shooting electrical currents across your brain can boost learning, I thought it was a joke. But evidence is mounting. According to a handful of studies, transcranial direct current stimulation (tDCS), the poster child of brain stimulation, is a bona fide cognitive booster: By directly tinkering with the brain’s electrical field, some research has found that tDCS enhances creativity, bolsters spatial and math learning and even language aquisition – sometimes weeks after the initial zap. For those eager to give their own brains a boost, this is good news. Various communities have sprung up to share tips and tricks on how to test the technique on themselves, often using self-rigged stimulators powered by 9-volt batteries. Scientists and brain enthusiasts aren’t the only people interested. The military has also been eager to support projects involving brain stimulation with the hope that the technology could one day be used to help soldiers suffering from combat-induced memory loss. But here’s the catch: The end results are inconsistent at best. While some people swear by the positive effects anecdotally, others report nothing but a nasty scalp burn from the electrodes. In a meta-analysis covering over 20 studies, a team from Australia found no significant effects of tDCS on memory. Similar disparities pop up for other brain stimulation techniques. It’s not that brain stimulation isn’t doing anything – it just doesn’t seem to be doing something consistently across a diverse population. So what gives? © 2010–2017, The Conversation US, Inc.

Keyword: Learning & Memory
Link ID: 23624 - Posted: 05.17.2017

Sarah Boseley People who are obese run an increased risk of heart failure and stroke even if they appear healthy, without the obvious warning signs such as high blood pressure or diabetes, according to a major new study. The findings, presented at the European Congress on Obesity in Porto, Portugal, may be the final death knell for the claim that it is possible to be obese but still metabolically healthy – or “fat but fit” – say scientists. Several studies in the past have suggested that the idea of “metabolically healthy” obese individuals is an illusion, but they have been smaller than this one. The new study, from the University of Birmingham, involved 3.5 million people, approximately 61,000 of whom developed coronary heart disease. Is it possible to be healthy and obese? The issue has been controversial. Obesity is usually measured by body mass index (BMI) – a ratio of weight against height. It is generally agreed to be imperfect because athletes and very fit people with dense muscle can have the same BMI as somebody who is obese. The scientists examined electronic health records from 1995 to 2015 in the Health Improvement Network – a large UK general practice database. They found records for 3.5 million people who were free of coronary heart disease at the starting point of the study and divided them into groups according to their BMI and whether they had diabetes, high blood pressure [hypertension], and abnormal blood fats [hyperlipidemia], which are all classed as metabolic abnormalities. Anyone who had none of those was classed as “metabolically healthy obese”.

Keyword: Obesity
Link ID: 23623 - Posted: 05.17.2017