Hannah Devlin Science Correspondent Scientists have offered a genetic explanation for why some people are obese and healthy while others develop diabetes and heart disease as a result of their weight. The study identified three genes, which appear to influence whether fat is compartmentalised and stored around the outside of the body or whether it spills into the circulatory system. Higher levels of fat in the blood supply increase the risk of type 2 diabetes and can lead to fatty deposits around the heart and liver. Professor Haja Kadarmideen, a geneticist who led the work at the University of Copenhagen, said: “People who have the ability to store large amounts of fat are able to be fat, but not unhealthy.” Yo-yo weight gain driven by gut bacteria's 'memory' of obesity, says study Read more Previous studies have found that while being overweight or obese is a risk factor for diabetes, liver disease and heart disease, about 15-20% of those who are obese appear to suffer no health consequences. Other research, involving more than 100,000 adults in Denmark, found that those with an “overweight” body mass index (or BMI) were more likely to live longer than those in the “healthy”, “underweight”, and “obese” categories, suggesting that the relationship between weight, health and lifespan is not straightforward. “We wanted to ask what is it that allows some people to be overweight and remain healthy,” said Kadarmideen. © 2016 Guardian News and Media Limited

Keyword: Obesity; Genes & Behavior
Link ID: 23005 - Posted: 12.22.2016

By Victoria Gill Science reporter, BBC News Direct recordings have revealed what is happening in our brains as we make sense of speech in a noisy room. Focusing on one conversation in a loud, distracting environment is called "the cocktail party effect". It is a common festive phenomenon and of interest to researchers seeking to improve speech recognition technology. Neuroscientists recorded from people's brains during a test that recreated the moment when unintelligible speech suddenly makes sense. A team measured people's brain activity as the words of a previously unintelligible sentence suddenly became clear when a subject was told the meaning of the "garbled speech". The findings are published in the journal Nature Communications. Lead researcher Christopher Holdgraf from the University of California, Berkeley, and his colleagues were able to work with epilepsy patients, who had had a portion of their skull removed and electrodes placed on the brain surface to track their seizures. First, the researchers played a very distorted, garbled sentence to each subject, which almost no-one was able to understand. They then played a normal, easy to understand version of the same sentence and immediately repeated the garbled version. "After hearing the intact sentence" the researchers explained in their paper, all the subjects understood the subsequent "noisy version". The brain recordings showed this moment of recognition as brain activity patterns in the areas of the brain that are known to be associated with processing sound and understanding speech. When the subjects heard the very garbled sentence, the scientists reported that they saw little activity in those parts of the brain. Hearing the clearly understandable sentence then triggered patterns of activity in those brain areas. © 2016 BBC.

Keyword: Attention; Hearing
Link ID: 23004 - Posted: 12.22.2016

Dhruv Khullar My patient and I both knew he was dying. Not the long kind of dying that stretches on for months or years. He would die today. Maybe tomorrow. And if not tomorrow, the next day. Was there someone I should call? Someone he wanted to see? Not a one, he told me. No immediate family. No close friends. He had a niece down South, maybe, but they hadn’t spoken in years. For me, the sadness of his death was surpassed only by the sadness of his solitude. I wondered whether his isolation was a driving force of his premature death, not just an unhappy circumstance. Every day I see variations at both the beginning and end of life: a young man abandoned by friends as he struggles with opioid addiction; an older woman getting by on tea and toast, living in filth, no longer able to clean her cluttered apartment. In these moments, it seems the only thing worse than suffering a serious illness is suffering it alone. Social isolation is a growing epidemic — one that’s increasingly recognized as having dire physical, mental and emotional consequences. Since the 1980s, the percentage of American adults who say they’re lonely has doubled from 20 percent to 40 percent. About one-third of Americans older than 65 now live alone, and half of those over 85 do. People in poorer health — especially those with mood disorders like anxiety and depression — are more likely to feel lonely. Those without a college education are the least likely to have someone they can talk to about important personal matters. © 2016 The New York Times Company

Keyword: Stress
Link ID: 23003 - Posted: 12.22.2016

Laura Sanders Pregnancy changes nearly everything about an expectant mother’s life. That includes her brain. Pregnancy selectively shrinks gray matter to make a mom’s brain more responsive to her baby, and those changes last for years, scientists report online December 19 in Nature Neuroscience. “This study, coupled with others, suggests that a women’s reproductive history can have long-lasting, possibly permanent changes to her brain health,” says neuroscientist Liisa Galea of the University of British Columbia in Vancouver, who was not involved in the study. Researchers performed detailed anatomy scans of the brains of 25 women who wanted to get pregnant with their first child. More scans were performed about two months after the women gave birth. Pregnancy left signatures so strong that researchers could predict whether women had been pregnant based on the changes in their brains. The women who had carried a child and given birth had less gray matter in certain regions of their brains compared with 20 women who had not been pregnant, 19 first-time fathers and 17 childless men. These changes were still evident two years after pregnancy. A shrinking brain sounds bad, but “reductions in gray matter are not necessarily a bad thing,” says study coauthor Elseline Hoekzema, a neuroscientist at Leiden University in the Netherlands. A similar reduction happens during adolescence, a refinement that is “essential for a normal cognitive and emotional development,” says Hoekzema, who, along with colleagues, did most of the work at Universitat Autònoma de Barcelona. Following those important teenage years, pregnancy could be thought of almost as a second stage of brain maturing, she says. |© Society for Science & the Public 2000 - 2016.

Keyword: Sexual Behavior; Hormones & Behavior
Link ID: 23002 - Posted: 12.20.2016

By STEVEN PETROW “So why did you stop drinking?” my friend Brad asked recently when we were out for dinner. “You never seemed to have a drinking problem.” The question surprised me, coming as it did a full two years after my decision to take a “break” from alcohol. He was scanning the wine list, and I sensed he was hoping I’d share a bottle of French rosé with him. So I decided to tell him the truth. “To get my depression back under control.” In my late 50s, my longstanding depression had started to deepen, albeit imperceptibly at first. I continued drinking moderately, a couple of glasses of wine most days of the week, along with a monthly Manhattan. Then two dark and stormy months really shook me up, leaving me in a black hole of despair as depression closed in. At my first therapy appointment, the psychopharmacologist listened to me attentively, then said bluntly: “Stop drinking for a month.” The shrink wanted to know whether I was in control of my drinking or my drinking was in control of me. He explained that we become more sensitive to the depressant effects of alcohol as we age, especially in midlife, when our body chemistry changes and we’re more likely to be taking various medications that can interact with alcohol and one another. On doctor’s orders, I went cold turkey off alcohol. When I returned a month later and volunteered that I hadn’t touched a drink since our last visit, he was satisfied that I didn’t have “an active alcohol problem” and told me I could drink in what he considered moderation: No more than two glasses of wine a day, and never two days in a row. He also suggested I keep a log. © 2016 The New York Times Company

Keyword: Depression; Drug Abuse
Link ID: 23001 - Posted: 12.20.2016

By Sara Reardon The din of what sounds like a high-pitched cocktail party fills the lab of neuroscientist Xiaoqin Wang at Johns Hopkins University in Baltimore. But the primates making the racket are dozens of marmosets, squirrel-sized monkeys with patterned coats and white puffs of fur on either side of their heads. The animals chatter to each other, stopping to tilt their heads and consider their visitors with inquisitive expressions. Common marmosets (Callithrix jacchus) are social and communicative in captivity, unlike the macaque that is more commonly used as a model primate. And in January, Wang and his colleagues revealed that marmosets are also the only non-human animal that can hear different pitches, such as those found in music and tonal languages like Chinese, in the same way people can1. This makes the marmoset the closest proxy researchers have to the human brain when it comes to hearing and speech, says Quianjie Fu, an auditory researcher at the University of California, Los Angeles, who was not involved with the paper. Until recently, researchers have relied on songbirds for such work, but the birds’ brains are so different from human ones that the insights they provide are limited. Wang hopes that marmosets will improve researchers’ understanding of the evolution of communication and help them refine devices such as cochlear implants for deaf people. © 2016 Scientific American

Keyword: Hearing
Link ID: 23000 - Posted: 12.20.2016

By Vik Adhopia, CBC News Every eight minutes someone in Canada has a stroke. But the odds of survival are getting better because of a new emergency intervention being offered at 22 hospitals across Canada. Spencer Higdon, 63, successfully received the procedure at Toronto Western Hospital in April after suddenly collapsing in his bathroom. "I was stepping into the shower and I dropped like a tonne of bricks." he said. When he regained consciousness he knew he'd had a stroke. "I couldn't move my right leg, my right arm, I couldn't speak, and I had difficulty moving my head." Physicians confirmed he'd had an ischemic stroke — a blood clot in his brain. Unless the blockage was cleared within a few hours, his paralysis would likely be permanent, or worse, he'd die. Higdon later learned from one of the treating physicians that because of the position of the clot in the brainstem, the consequences of his stroke could have been devastating. "She said it's called 'locked-in syndrome,' where your brain works just fine but nothing else in your body moves. You're lying in a bed and the only way to communicate is through your eyes. And that just horrified me." The procedure used to remove Higdon's clot, known as a thrombectomy, involves feeding a tiny catheter into an artery near the groin, all the way up into the brain and through the blockage. The device is expanded to grab the clot. Then it's pulled out, allowing the blood to flow again. Advanced imaging equipment helps navigate the catheter. For Higdon, the entire procedure took eight minutes, a record for the stroke team at Toronto Western. ©2016 CBC/Radio-Canada.

Keyword: Stroke
Link ID: 22999 - Posted: 12.20.2016

By Kate Baggaley In American schools, bullying is like the dark cousin to prom, student elections, or football practice: Maybe you weren’t involved, but you knew that someone, somewhere was. Five years ago, President Obama spoke against this inevitability at the White House Conference on Bullying Prevention. “With big ears and the name that I have, I wasn’t immune. I didn’t emerge unscathed,” he said. “But because it’s something that happens a lot, and it’s something that’s always been around, sometimes we’ve turned a blind eye to the problem.” We know that we shouldn’t turn a blind eye: Research shows that bullying is corrosive to children’s mental health and well-being, with consequences ranging from trouble sleeping and skipping school to psychiatric problems, such as depression or psychosis, self-harm, and suicide. But the damage doesn’t stop there. You can’t just close the door on these experiences, says Ellen Walser deLara, a family therapist and professor of social work at Syracuse University, who has interviewed more than 800 people age 18 to 65 about the lasting effects of bullying. Over the years, deLara has seen a distinctive pattern emerge in adults who were intensely bullied. In her new book, Bullying Scars, she introduces a name for the set of symptoms she often encounters: adult post-bullying syndrome, or APBS. DeLara estimates that more than a third of the adults she’s spoken to who were bullied have this syndrome. She stresses that APBS is a description, not a diagnosis—she isn’t seeking to have APBS classified as a psychiatric disorder. “It needs considerably more research and other researchers to look at it to make sure that this is what we’re seeing,” deLara says.

Keyword: Stress; Development of the Brain
Link ID: 22998 - Posted: 12.20.2016

By Catherine Matacic Have you ever wondered why a strange piece of music can feel familiar—how it is, for example, that you can predict the next beat even though you’ve never heard the song before? Music everywhere seems to share some “universals,” from the scales it uses to the rhythms it employs. Now, scientists have shown for the first time that people without any musical training also create songs using predictable musical beats, suggesting that humans are hardwired to respond to—and produce—certain features of music. “This is an excellent and elegant paper,” says Patrick Savage, an ethnomusicologist at the Tokyo University of the Arts who was not involved in the study. “[It] shows that even musical evolution obeys some general rules [similar] to the kind that govern biological evolution.” Last year, Savage and colleagues traced that evolution by addressing a fundamental question: What aspects of music are consistent across cultures? They analyzed hundreds of musical recordings from around the world and identified 18 features that were widely shared across nine regions, including six related to rhythm. These “rhythmic universals” included a steady beat, two- or three-beat rhythms (like those in marches and waltzes), a preference for two-beat rhythms, regular weak and strong beats, a limited number of beat patterns per song, and the use of those patterns to create motifs, or riffs. “That was a really remarkable job they did,” says Andrea Ravignani, a cognitive scientist at the Vrije Universiteit Brussel in Belgium. “[It convinced me that] the time was ripe to investigate this issue of music evolution and music universals in a more empirical way.” © 2016 American Association for the Advancement of Science.

Keyword: Hearing
Link ID: 22997 - Posted: 12.20.2016

By GINA KOLATA As concern rises over the effect of continuous use of headphones and earbuds on hearing, a new paper by federal researchers has found something unexpected. The prevalence of hearing loss in Americans of working age has declined. The paper, published on Thursday in the journal JAMA Otolaryngology — Head & Neck Surgery, used data from the National Health and Nutrition Survey, which periodically administers health tests to a representative sample of the population. The investigators, led by Howard J. Hoffman, the director of the epidemiology and statistics program at the National Institute on Deafness and Other Communication Disorders, compared data collected between 1999 and 2004 with data from 2011 and 2012, the most recent available. Hearing loss in this study meant that a person could not hear, in at least one ear, a sound about as loud as rustling leaves. The researchers reported that while 15.9 percent of the population studied in the earlier period had problems hearing, just 14.1 percent of the more recent group had hearing loss. The good news is part of a continuing trend — Americans’ hearing has gotten steadily better since 1959. Most surprising to Mr. Hoffman, a statistician, was that even though the total population of 20- to 69-year-olds grew by 20 million over the time period studied — and the greatest growth was in the oldest people, a group most likely to have hearing problems — the total number of people with hearing loss fell, from 28 million to 27.7 million. Hearing experts who were not associated with the study said they were utterly convinced by the results. “It’s a fantastic paper,” said Brian Fligor, an audiologist with Lantos Technologies of Wakefield, Mass., which develops custom earpieces to protect ears from noise. “I totally believe them.” © 2016 The New York Times Company

Keyword: Hearing
Link ID: 22996 - Posted: 12.17.2016

Joy Ho The hipbone's connected to the leg bone, connected to the knee bone. That's not actually what those body parts are called, but we'll forgive you if you don't sing about the innominate bone connecting to the femur connecting to the patella. It just doesn't have the same ring to it. When the ancient Greeks were naming body parts, they were probably trying to give them names that were easy to remember, says Mary Fissell, a professor in the Department of the History of Medicine at Johns Hopkins. "Sure, there were texts, but the ancient world was very oral, and the people learning this stuff have to remember it." So the Greek scholars, and later Roman and medieval scholars, named bones and organs and muscles after what they looked like. The thick bone at the front of your lower leg, the tibia, is named after a similar-looking flute. And although you or I might get confused when a paleoanthropologist writes about the foramen magnum (which translates to "really big hole") a native Latin speaker would know exactly what to look for — the really big hole where your brain attaches to your spine. Sometimes the names get a little bit more abstract. Take the tragus, a tiny flap of skin on the outer ear. It's named after goats not because it looks like them, but because some people have tufts of hair on the tragus like goats do on their chins. "I'm fascinated by the struggle of translating sensory experiences to words, and that's what these early anatomists were doing. Sometimes in the names or descriptions you can almost feel the struggle of someone seeing this object and trying to reduce it to words,"says Fissell. © 2016 npr

Keyword: Brain imaging
Link ID: 22995 - Posted: 12.17.2016

By Sarah DeWeerdt, Toddlers with autism are oblivious to the social information in the eyes, but don’t actively avoid meeting another person’s gaze, according to a new study. The findings support one side of a long-standing debate: Do children with autism tend not to look others in the eye because they are uninterested or because they find eye contact unpleasant? “This question about why do we see reduced eye contact in autism has been around for a long time,” says study leader Warren Jones, director of research at the Marcus Autism Center in Atlanta, Georgia. “It’s important for how we understand autism, and it’s important for how we treat autism.” If children with autism dislike making eye contact, treatments could incorporate ways to alleviate the discomfort. But if eye contact is merely unimportant to the children, parents and therapists could help them understand why it is important in typical social interactions. The work also has implications for whether scientists who study eye contact should focus on social brain regions rather than those involved in fear and anxiety. Lack of eye contact is among the earliest signs of autism, and its assessment is part of autism screening and diagnostic tools. Yet researchers have long debated the underlying mechanism. The lack-of-interest hypothesis is consistent with the social motivation theory, which holds that a broad disinterest in social information underlies autism features. On the other hand, anecdotal reports from people with autism suggest that they find eye contact unpleasant. Studies that track eye movements as people view faces have provided support for both hypotheses. © 2016 Scientific American

Keyword: Autism
Link ID: 22994 - Posted: 12.17.2016

Older folks tend not to engage as much in risky behavior as teenagers and young adults do. You might call that wisdom or learned experience. But this also may be a result of older brains having less gray matter in a certain spot, according to a new study. Researchers found that adults who were less inclined to take risks had less gray matter in the right posterior parietal cortex, which is involved in decisions that entail risk. In the study, the researchers asked volunteers ranging in age from 18 to 88 to play a game involving risk. The participants were allowed to choose between a guaranteed gain, such as pocketing $5, or an uncertain gain, such as a lottery to earn between $5 and $120 with varying chances of winning or losing. As the researchers expected, those participants who chose the guaranteed gain — that is, no risk — tended to be older than those who opted for the lottery. It wasn’t a perfect correlation, but it was close. One could call this old-age wisdom. Yet when the researchers analyzed brain scans of these volunteers obtained through an MRI technique called voxel-based morphometry (VBM), they found that lower levels of gray matter, even more than age, best accounted for risk aversion. These results suggest that the brain changes that occur in healthy aging people may be behind more decision-making patterns and preferences than previously thought, the researchers noted in their findings, published Dec. 13 in the journal Nature Communications. © 1996-2016 The Washington Post

Keyword: Development of the Brain
Link ID: 22993 - Posted: 12.17.2016

By PHIL BARBER SAN FRANCISCO — Paraag Marathe’s structured, analytical mind has served him well in the offices of Silicon Valley and the National Football League. He figured that he could lean on those traits the first time he spoke publicly about his sister, Shilpa, and how anorexia had taken her life. But composure failed Marathe in 2011, six years after Shilpa’s death, while he spoke to survivors and grieving family members at an event for Andrea’s Voice, a nonprofit foundation that tries to promote education about eating disorders and their treatments. “Not only did I break down a little bit during that speech,” said Marathe, 39, the San Francisco 49ers’ chief strategy officer and executive vice president for football operations. “It was also one of those weird moments afterwards. I emotionally collapsed in the arms of somebody there who had lost her daughter.” The memories were back. Marathe had watched his brilliant sister succumb to self-destructive thoughts and starve herself. He had seen Shilpa wither to less than 50 pounds in the last years of her life, had felt the shame and puzzlement that her condition brought to his family. Fueled by regret — why had he not noticed sooner, and why wasn’t he more assertive in trying to help Shilpa? — Marathe has found his voice. He will patiently tell you that 30 million Americans are believed to suffer from eating disorders, and that medical insurance plans rarely cover treatment of the condition. He will remind you that anorexia has the highest fatality rate among mental illnesses — about 10 percent, according to a 2011 meta-analysis published in Archives of General Psychiatry and cited by the National Institute of Mental Health. Eating-disorder caregivers and advocates welcome Marathe’s help in shattering the myth that anorexia afflicts only well-to-do white girls and women. The illness claims men, too, and frequently remains a taboo subject in less affluent or nonwhite families, said Kristina Saffran of Project HEAL, an organization that raises money to cover care from diagnosis to recovery. © 2016 The New York Times Company

Keyword: Anorexia & Bulimia
Link ID: 22992 - Posted: 12.15.2016

By Kai Kupferschmidt New York City is known for its strange sights. But on 12 July, even locals were shocked by what they saw: more than 30 people staggering around a Brooklyn block with empty stares, shuffling their arms and feet and occasionally groaning. What sounds like the opening of a horror movie was suspected from the start to be the work of a synthetic cannabinoid. Now, a new analysis, out today in The New England Journal of Medicine, confirms those suspicions. But it has also raised scientific ire over its prolific use of the word “zombie.” Developed by academics and pharma companies to study cannabinoid receptors in the human body, synthetic cannabinoids act on the same receptor on brain cells as cannabis. The compounds, which can be up to 100 times more potent than cannabis, are a rapidly growing class of drugs, usually dissolved in liquid and sprayed on leaves to be smoked. There are hundreds of different compounds, and though they are quickly made illegal in many places, new ones appear every year. To find out what was responsible for the Brooklyn episode, researchers from the University of California, San Francisco (UCSF), started with a foil-wrapped pouch of herbs found on one of the patients, labeled “AK-47 24 Karat Gold.” When they analyzed a sample, they found it contained the substance AMB-FUBINACA, a powerful synthetic cannabinoid similar to a compound first patented by Pfizer in 2009. The researchers also found breakdown products of AMB-FUBINACA in the blood of eight patients. © 2016 American Association for the Advancement of Science

Keyword: Drug Abuse
Link ID: 22991 - Posted: 12.15.2016

By DONALD G. McNEIL Jr. and PAM BELLUCK Babies born to Zika-infected mothers are highly likely to have brain damage, even in the absence of obvious abnormalities like small heads, and the virus may go on replicating in their brains well after birth, according to three studies published Tuesday. Many types of brain damage were seen in the studies, including dead spots and empty spaces in the brain, cataracts and congenital deafness. There were, however, large differences among these studies in how likely it was that a child would be hurt by the infection. One study, published by The Journal of the American Medical Association, assessed 442 pregnancies registered with the Centers for Disease Control and Prevention between January and September in the continental United States and Hawaii, most of them in returning travelers. That report found that 6 percent had birth defects. None of those birth defects occurred in infants born to women infected in the second or third trimester. By contrast, in a study of 125 Zika-infected women in Rio de Janeiro done by Brazilian and American scientists and released by The New England Journal of Medicine, almost half of pregnancies had “adverse outcomes,” ranging from fetal deaths to serious brain damage. Of the 117 infants born alive, 42 percent had “grossly abnormal” brain scans or physical symptoms, the authors said. Other studies from Colombia, Brazil and French Polynesia have suggested that brain damage rates are between 1 and 13 percent. But each one uses different measurements of brain damage and different definitions of which mothers to include, so the question remains unanswered. © 2016 The New York Times Company

Keyword: Development of the Brain
Link ID: 22990 - Posted: 12.15.2016

By James Gallagher Health and science reporter, BBC News website Detailed MRI scans should be offered to some women in pregnancy to help spot brain defects in the developing baby, say researchers. Ultrasounds are already used to look inside the womb and check that the baby is growing properly. However, the study on 570 women published in the Lancet showed doctors were able to make a much better diagnosis using MRI scans. Experts called for the scans to become routine practice. Pregnant women are offered an ultrasound scan at about 20 weeks that can spot abnormalities in the brain. They are detected in three in every 1,000 pregnancies. If the brain fails to develop properly it can result in miscarriage or still birth. Couples are generally offered counselling and some choose to have an abortion More certainty The study, carried out across 16 centres in the UK, analysed the impact of using MRI scans - which use magnetic fields and radio waves to image the body - to confirm any diagnoses. Overall, it showed ultrasound gave the correct diagnosis 68% of the time. But combining that with MRI increased the accuracy to 93%. Image copyright SPL Image caption The detailed picture of the developing baby's brain revealed by MRI The extra tests were most useful in borderline cases where doctors were uncertain of the outcome. The number of pregnant women who were given an "unknown" diagnosis was more than halved by the extra scans, increasing the confidence that the developing baby's brain was healthy or not. © 2016 BBC.

Keyword: Brain imaging; Development of the Brain
Link ID: 22989 - Posted: 12.15.2016

The important role vitamin D plays in early life is back in the spotlight after Australian researchers noticed a link between a deficiency during pregnancy and autism. The study found pregnant women with low vitamin D levels at 20 weeks’ gestation were more likely to have a child with autistic traits by the age of six. The finding has led to calls for the widespread use of vitamin D supplements during pregnancy, just as taking folate has reduced the incidence of spina bifida in the community. “This study provides further evidence that low vitamin D is associated with neurodevelopmental disorders,” said Professor John McGrath from the University of Queensland’s Brain Institute, who led the research alongside Dr Henning Tiemeier from the Erasmus Medical Centre in the Netherlands. McGrath said supplements might reduce the incidence of autism, a lifelong developmental condition that affects, among other things, how an individual relates to their environment and other people. “We would not recommend more sun exposure, because of the increased risk of skin cancer in countries like Australia,” he said. “Instead, it’s feasible that a safe, inexpensive, and publicly accessible vitamin D supplement in at-risk groups may reduce the prevalence of this risk factor.” Vitamin D usually comes from exposure to the sun, but it can also be found in some foods and supplements. While it’s widely known vitamin D is vital for maintaining healthy bones, there’s also a solid body of evidence linking it to brain growth. © 2016 Guardian News and Media Limited

Keyword: Autism
Link ID: 22988 - Posted: 12.14.2016

By Claire Asher We pride ourselves on our big brains, but when it comes to figuring out whether people or other animals with particularly big brains do better than others, the evidence has been lacking. Now, for the first time, a study in red deer is showing that bigger brained mammals tend to be more successful in the wild, and that brain size is a heritable trait that they can pass on to their offspring. Corina Logan from the University of Cambridge and her team have looked at the skulls of 1314 red deer (Cervus elaphus) from the Isle of Rum. The complete life histories of the deer are well known thanks to the Isle of Rum Red Deer Project, which has been collecting data on the island for more than 40 years, spanning seven deer generations. “This kind of study has not been conducted before because it requires long-term data from a large number of individuals,” says Logan. Heritable heads The team found that the ratio of skull volume to body size was highly heritable, explaining 63 per cent of variation between individuals. Female deer with larger skulls lived significantly longer and raised more offspring to adulthood, though it’s not clear yet why bigger brains are advantageous to females. © Copyright Reed Business Information Ltd.

Keyword: Sexual Behavior; Evolution
Link ID: 22987 - Posted: 12.14.2016

A little over a decade ago, neuroscientists began using a new technique to inspect what was going on in the brains of their subjects. Rather than giving their subjects a task to complete and watching their brains to see which parts lit up, they’d tell them to lie back, let their minds wander, and try not to fall asleep for about six minutes. That technique is called resting state functional magnetic resonance imaging, and it shares a problem with other types of fMRI: It only tracks changes in the blood in the brain, not the neurons sending the signals in the first place. Researchers have recently called fMRI into question for its reliance on possibly-faulty statistics. And things get even less certain when the brain isn’t engaged in any particular task. “These signals are, by definition, random,” says Elizabeth Hillman, a biomedical engineer at Columbia’s Zuckerman Institute. “And when you’re trying to measure something that’s random amidst a whole bunch of noise, it becomes very hard to tell what’s actually random and what isn’t.” Six years ago, Hillman, along with many others in the field, was deeply skeptical of resting state fMRI’s ability to measure what it promised to. But this week, in a paper in Proceedings of the National Academy of Sciences, she presents compelling evidence to the contrary: a comprehensive visualization of neural activity throughout the entire brain at rest, and evidence that the blood rushing around in your brain is actually a good indicator of what your neurons are doing. Ever since 1992, when researcher Bharat Biswal first started scanning people who were just sitting around, resting state fMRI has become increasingly popular. Partly, that’s because it’s just way simpler than regular, task-based fMRI.

Keyword: Brain imaging; Attention
Link ID: 22986 - Posted: 12.14.2016