By Joe Ward, Josh Williams and Sam Manchester Dr. Ann McKee, a neuropathologist, has examined the brains of 202 deceased football players. A broad survey of her findings was published on Tuesday in The Journal of the American Medical Association. Of the 202 players, 111 of them played in the N.F.L. — and 110 of those were found to have chronic traumatic encephalopathy, or C.T.E., the degenerative disease believed to be caused by repeated blows to the head. C.T.E. causes myriad symptoms, including memory loss, confusion, depression and dementia. The problems can arise years after the blows to the head have stopped. The brains here are from players who died as young as 23 and as old as 89. And they are from every position on the field — quarterbacks, running backs and linebackers, and even a place-kicker and a punter. They are from players you have never heard of and players, like Ken Stabler, who are enshrined in the Hall of Fame. Some of the brains cannot be publicly identified, per the families’ wishes. The image above is from the brain of Ronnie Caveness, a linebacker for the Houston Oilers and Kansas City Chiefs. In college, he helped the Arkansas Razorbacks go undefeated in 1964. One of his teammates was Jerry Jones, now the owner of the Dallas Cowboys. Jones has rejected the belief that there is a link between football and C.T.E. The image above is from the brain of Ollie Matson, who played 14 seasons in the N.F.L. — after winning two medals on the track at the 1952 Helsinki Games. He died in 2011 at age 80 after being mostly bedridden with dementia, his nephew told The Associated Press, adding that Matson hadn’t spoken in four years. Dr. McKee, chief of neuropathology at the VA Boston Healthcare System and director of the CTE Center at Boston University, has amassed the largest C.T.E. brain bank in the world. But the brains of some other players found to have the disease — like Junior Seau, Mike Webster and Andre Waters — were examined elsewhere. © 2017 The New York Times Company

Keyword: Brain Injury/Concussion
Link ID: 23880 - Posted: 07.26.2017

Tom Goldman As the country starts to get back into its most popular professional team sport, there is a reminder of how dangerous football can be. An updated study published Tuesday by the Journal of the American Medical Association on football players and the degenerative brain disease chronic traumatic encephalopathy reveals a striking result among NFL players. The study examined the brains of deceased former football players (CTE can only be diagnosed after death) and found that 110 out of 111 brains of those who played in the NFL had CTE. CTE has been linked to repeated blows to the head — the 2015 movie Concussion chronicled the discovery of CTE's connection to football. In the study, researchers examined the brains of 202 deceased former football players at all levels. Nearly 88 percent of all the brains, 177, had CTE. Three of 14 who had played only in high school had CTE, 48 of 53 college players, 9 of 14 semiprofessional players, and 7 of 8 Canadian Football League players. CTE was not found in the brains of two who played football before high school. According to the study's senior author, Dr. Ann McKee, "this is by far the largest [study] of individuals who developed CTE that has ever been described. And it only includes individuals who are exposed to head trauma by participation in football." © 2017 npr

Keyword: Brain Injury/Concussion
Link ID: 23879 - Posted: 07.26.2017

by Tom Siegfried Scientists pour a lot of brainpower into understanding how their experimental equipment works. You don’t want to be fooled into thinking you’ve made a great discovery because of some quirk in the apparatus you didn’t know about. Just the other day, a new paper published online suggested that the instruments used to detect gravitational waves exhibited such a quirk, tricking scientists into claiming the detection of waves that maybe weren’t really there. It appears that gravity wave fans can relax, though. A response to the challenge pretty much establishes that the new criticism doesn’t undermine the wave discoveries. Of course, you never know — supposedly well-established results sometimes do fade away. Often that’s because scientists have neglected to understand the most important part of the entire experimental apparatus — their own brains. It’s the brain, after all, that devises experiments and interprets their results. How the brain perceives, how it makes decisions and judgments, and how those judgments can go awry are at least as important to science as knowing the intricacies of nonbiotic experimental machinery. And as any brain scientist will tell you, there’s still a long way to go before understanding the brain will get crossed off science’s to-do list. But there has been progress. A recent special issue of the journal Neuron offers a convenient set of “perspective” papers exploring the current state of understanding of the brain’s inner workings. Those papers show that a lot is known. But at the same time they emphasize that there’s a lot we don’t know. |© Society for Science & the Public 2000 - 2017

Keyword: Miscellaneous
Link ID: 23878 - Posted: 07.26.2017

By Virginia Morell Frogs, birds, monkeys, and humans make a variety of sounds expressing emotions. And because that ability is shared by every land-dwelling animal with a backbone, Charles Darwin argued that these cries have a common origin. Humans can recognize the emotions in the voices of other mammals, including cats and dogs. To find out whether we can also do this for nonmammals, scientists gathered recordings from nine species, including the hourglass tree frog (above), American alligator, common raven, Barbary macaque, and Tamil-speaking humans in two emotional states: highly and mildly aroused. They played the calls to 75 people—men and women who spoke English, German, or Mandarin—and asked them to judge whether the animal was very excited or subdued. You can try it yourself below: Participants easily passed the tests. Some 90% of listeners distinguished between the excited and calmer sounds of the tree frogs (which were calling for mates), and 87% scored the alligator calls correctly. Sixty-two percent were right about the ravens’ calls of alarm. © 2017 American Association for the Advancement of Science.

Keyword: Animal Communication; Emotions
Link ID: 23877 - Posted: 07.26.2017

By BENEDICT CAREY LONDON — England is in the midst of a unique national experiment, the world’s most ambitious effort to treat depression, anxiety and other common mental illnesses. The rapidly growing initiative, which has gotten little publicity outside the country, offers virtually open-ended talk therapy free of charge at clinics throughout the country: in remote farming villages, industrial suburbs, isolated immigrant communities and high-end enclaves. The goal is to eventually create a system of primary care for mental health not just for England but for all of Britain. At a time when many nations are debating large-scale reforms to mental health care, researchers and policy makers are looking hard at England’s experience, sizing up both its popularity and its limitations. Mental health care systems vary widely across the Western world, but none have gone nearly so far to provide open-ended access to talk therapies backed by hard evidence. Experts say the English program is the first broad real-world test of treatments that have been studied mostly in carefully controlled lab conditions. The demand in the first several years has been so strong it has strained the program’s resources. According to the latest figures, the program now screens nearly a million people a year, and the number of adults in England who have recently received some mental health treatment has jumped to one in three from one in four and is expected to continue to grow. Mental health professionals also say the program has gone a long way to shrink the stigma of psychotherapy in a nation culturally steeped in stoicism. “You now actually hear young people say, ‘I might go and get some therapy for this,’” said Dr. Tim Kendall, the clinical director for mental health for the National Health Service. “You’d never, ever hear people in this country say that out in public before.” A recent widely shared video of three popular royals — Prince William, Prince Harry and Kate, Dutchess of Cambridge — discussing the importance of mental health care and the princes’ struggles after their mother’s death is another sign of the country’s growing openness about treatment. © 2017 The New York Times Company

Keyword: Depression
Link ID: 23876 - Posted: 07.25.2017

/ By Ed Cara Ariella Cohen had already made nearly a dozen visits in as many months to a Philadelphia emergency room when, in the winter of 2014, she once again grabbed her pre-packed overnight bag and rushed to the hospital with crippling intestinal pain. She didn’t have high expectations: At just 26, she and her family had seen close to 100 doctors and amassed hundreds of thousands of dollars in medical bills attempting to identify and treat the source of her pain, and she arrived with a long-ago memorized script of the many diagnoses she had received since her childhood. As she sat on a gurney, Cohen recalls calmly explaining her situation to the attending physician. Like so many times before, her body was in mutiny: The assembly line of muscles along her gut had frozen, and she had been constipated for months, with the resulting pain sometimes scorching her insides. That day it had become so horrendous that she collapsed, prompting two of her regular doctors, fearing that the stoppage might tear a hole in her lower intestine, to advise she go to the ER immediately. According to Cohen, the ER physician that day simply dismissed her symptoms without an examination. If anything was wrong, he implied, it was mental, not physical, and he refused to admit her. Later that winter, during a raging snowstorm, her agony came again, but despite calling ahead to the ER and being told she could see another physician, the same doctor came around again as she was being examined and told her to go home. Copyright 2017 Undark

Keyword: Depression
Link ID: 23875 - Posted: 07.25.2017

By Daisy Yuhas, When the shy, dark-haired boy met with clinicians for a full psychiatric evaluation two years ago, almost everything about him pointed to autism. W. had not spoken his first words until age 2. He was at least 4 before he could form sentences. As he got older, he was unable to make friends. He struggled to accept changes to his routine and maintain eye contact. And despite having an average intelligence quotient, he was unusually attached to objects; at age 11, he still lugged a bag of stuffed animals with him everywhere he went. But something else was clearly at work, too. “He had these things that he would call day dreams,” recalls Jennifer Foss-Feig, assistant professor of psychiatry at the Icahn School of Medicine at Mount Sinai in New York. When she evaluated W., she noticed that he would often gaze into an empty corner of the room—particularly when he seemed to suspect that she wasn’t paying attention to him. (For privacy reasons, Foss-Feig declined to reveal anything but the child’s first initial.) Occasionally, he would speak to that space, as though someone else were there. His parents, she recalls, were worried. They explained to Foss-Feig that their son had what he called an “imaginary family.” But W.’s invisible playmates weren’t of the usual harmless variety that many children have; they seemed to be a dangerous distraction both at home and at school. On one occasion, he wandered through a busy parking lot, seemingly oblivious to the oncoming traffic. © 2017 Scientific America

Keyword: Autism; Schizophrenia
Link ID: 23874 - Posted: 07.25.2017

By Aylin Woodward Keep your head up. Today, navigating the urban jungle can be challenging, with uneven sidewalks and errant kerbs presenting obstacles to easy walking. So why do we rarely trip up even though we hardly ever give walking our full attention? It seems that all we need is a brief glimpse of what’s coming next on the road in front of us, just one step ahead of time, to keep up upright. Humans have a unique kind of locomotion – we’re bipedal, meaning we move around on two legs rather than four. Scientists are still struggling to unravel the mystery behind our shift to two legs – for instance, some suggest it freed up our hands to carry food. Others point out that our human gait is much more energetically efficient. Our walking style exploits external forces like gravity and inertia to use as little muscular energy as possible so that we actually fall forward onto the lifted foot with each step. Jonathan Samir Matthis at the University of Texas at Austin wanted to know how we aim and control this forward motion – particularly since the way ahead is rarely level and obstacle-free. “We have to be much more careful about where we place our feet than we would if we had four legs on the ground,” he says. “Because if we do it wrong, there’s serious consequences like breaking your leg.” © Copyright New Scientist Ltd.

Keyword: Movement Disorders; Attention
Link ID: 23872 - Posted: 07.25.2017

Ryan Kellman The modern Planet of the Apes reboot begins with a research chimpanzee being raised in an American home. It's a pretty plausible premise — that exact scenario has played out in the real world many times. On June 26, 1931, for example, Luella and Winthrop Kellogg pulled a baby female chimpanzee away from her mother and brought her to live in their home in Orange Park, Fla. The Kelloggs were comparative psychologists. Their plan was to raise the chimpanzee, Gua, alongside their own infant son, Donald, and see if she picked up human language. According to the book they wrote about the experiment, Luella wasn't initially on board: ... the enthusiasm of one of us met with so much resistance from the other that it appeared likely we could never come to an agreement upon whether or not we should even attempt such an undertaking. But attempt it they did. The Kelloggs performed a slew of tests on Donald and Gua. How good were their reflexes? How many words did they recognize? How did they react to the sound of a gunshot? What sound did each infant's skull make when tapped by a spoon? (Donald's produced "a dull thud" while Gua's made the sound of a "mallet upon a wooden croquet ball.") Chimpanzees develop faster than humans, so Gua outshone Donald when it came to most tasks. She even learned to respond to English phrases like "Don't touch!" and "Get down!" But unlike the apes in the movies, Gua never learned to speak. © 2017 npr

Keyword: Language; Evolution
Link ID: 23871 - Posted: 07.25.2017

By Megan Scudellari Neuropharmacology postdoc Nick DiPatrizio was stumped. His advisor, University of California, Irvine, researcher Daniele Piomelli, had discovered eight years earlier that hungry rats have high levels of endocannabinoids, endogenous molecules that bind to the same receptors as the active ingredient in marijuana. Now, in 2009, DiPatrizio was trying to identify exactly where and how those molecules were controlling food intake in rats. But under specific feeding conditions, he couldn’t locate any changes in endocannabinoid levels in the brain, which is flush with endocannabinoid receptors and the obvious place to look for behavioral signals. Piomelli gently chastised his mentee. “He said, ‘You’re being neurocentric. Remember, there’s a body attached to the head. Look in the other organs of the body,’ ” recalls DiPatrizio. So the young scientist persisted, and eventually discovered that hunger—and the taste of fat—leads to increased endocannabinoid levels in the jejunum, a part of the small intestine. Endocannabinoid signaling in the gut, not the brain, was controlling food intake in the rodents in response to tasting fats.1 The evolution of endocannabinoid research has mirrored DiPatrizio’s early thinking: ever since the first endocannabinoid receptor was identified in the late 1980s, the field has been overwhelmingly focused on the central nervous system. The main endocannabinoid receptor, CB1, was first discovered in a rat brain and is now known to be among the most abundant G protein–coupled receptors in neurons there. Plus, cannabis is well-known for its psychotropic effects. “That has led the research field to be very CNS-oriented,” says Saoirse O’Sullivan, who studies endocannabinoids at the University of Nottingham in the U.K. © 1986-2017 The Scientist

Keyword: Drug Abuse; Obesity
Link ID: 23870 - Posted: 07.25.2017

By Neuroskeptic A number of so-called scientific journals have accepted a Star Wars-themed spoof paper. The manuscript is an absurd mess of factual errors, plagiarism and movie quotes. I know because I wrote it. Inspired by previous publishing “stings”, I wanted to test whether ‘predatory‘ journals would publish an obviously absurd paper. So I created a spoof manuscript about “midi-chlorians” – the fictional entities which live inside cells and give Jedi their powers in Star Wars. I filled it with other references to the galaxy far, far away, and submitted it to nine journals under the names of Dr Lucas McGeorge and Dr Annette Kin. Four journals fell for the sting. The American Journal of Medical and Biological Research (SciEP) accepted the paper, but asked for a $360 fee, which I didn’t pay. Amazingly, three other journals not only accepted but actually published the spoof. Here’s the paper from the International Journal of Molecular Biology: Open Access (MedCrave), Austin Journal of Pharmacology and Therapeutics (Austin) and American Research Journal of Biosciences (ARJ) I hadn’t expected this, as all those journals charge publication fees, but I never paid them a penny. So what did they publish? A travesty, which they should have rejected within about 5 minutes – or 2 minutes if the reviewer was familiar with Star Wars. Some highlights: “Beyond supplying cellular energy, midichloria perform functions such as Force sensitivity…”

Keyword: Miscellaneous
Link ID: 23869 - Posted: 07.25.2017

By CLAY ROUTLEDGE Are Americans becoming less religious? It depends on what you mean by “religious.” Polls certainly indicate a decline in religious affiliation, practice and belief. Just a couple of decades ago, about 95 percent of Americans reported belonging to a religious group. This number is now around 75 percent. And far fewer are actively religious: The percentage of regular churchgoers may be as low as 15 to 20 percent. As for religious belief, the Pew Research Center found that from 2007 to 2014 the percentage of Americans who reported being absolutely confident God exists dropped from 71 percent to 63 percent. Nonetheless, there is reason to doubt the death of religion, or at least the death of what you might call the “religious mind” — our concern with existential questions and our search for meaning. A growing body of research suggests that the evidence for a decline in traditional religious belief, identity and practice does not reflect a decline in this underlying spiritual inclination. Ask yourself: Why are people religious to begin with? One view is that religion is an ancient way of understanding and organizing the world that persists largely because societies pass it down from generation to generation. This view is related to the idea that the rise of science entails the fall of religion. It also assumes that the strength of religion is best measured by how much doctrine people accept and how observant they are. This view, however, does not capture the fundamental nature of the religious mind — our awareness of, and need to reckon with, the transience and fragility of our existence, and how small and unimportant we seem to be in the grand scheme of things. In short: our quest for significance. © 2017 The New York Times Company

Keyword: Attention; Emotions
Link ID: 23868 - Posted: 07.24.2017

By Erin Blakemore What do you see? That question is so complex it may be impossible to answer. But when Vanessa Potter lost her sight because of a rare condition, she became obsessed with describing the experience of both literal and inner vision. Patient H69: The Story of My Second Sight Book by Vanessa Potter Her new book, “Patient H69,” tracks Potter’s progression from advertising producer to patient. But her memoir shows how a medical ordeal also turned her into a scientific detective, advocate and artist. In 2012, Potter suddenly lost her sight. The first half of her book tracks her terrifying loss of vision and illustrates the psychological toll that accompanies the transition from healthy person to patient. Potter’s ailment turned out to be neuromyelitis optica, a disorder also known as Devic’s disease. People with the autoimmune disorder experience inflammation of the optic nerve, temporary blindness and spinal cord inflammation that can cause pain and sensory loss. Determined to regain her sight and understand her illness, Potter collaborated with scientists as her optical nerve healed.Along the way, she documented her experience. Her descriptive powers serve her well as she illustrates what it’s like to experience the development of sight in real time — a progression that, for Potter, included synesthesia (a blending of the senses in which a word may be seen as a certain color, for example), self-hypnosis and plenty of emotion. © 1996-2017 The Washington Post

Keyword: Vision; Neuroimmunology
Link ID: 23867 - Posted: 07.24.2017

By JANE E. BRODY Problems with estrogen and testosterone, the body’s main sex hormones, tend to attract widespread public interest. But we might all be better off paying more attention to a far more common endocrine disorder: abnormal levels of thyroid hormone. Thyroid disorders can affect a wide range of bodily functions and cause an array of confusing and often misdiagnosed symptoms. Because the thyroid, a small gland in the neck behind the larynx, regulates energy production and metabolism throughout the body, including the heart, brain, skin, bowels and body temperature, too much or too little of its hormones can have a major impact on health and well-being. Yet in a significant number of people with thyroid deficiencies, routine blood tests fail to detect insufficient thyroid hormone, leaving patients without an accurate explanation for their symptoms. These can include excessive fatigue, depression, hair loss, unexplained weight gain, constipation, sleep problems, mental fogginess and anxiety. Women of childbearing age may have difficulty getting pregnant or staying pregnant. Although thyroid disorders are more common in adults, children, whose cognitive and physical development depend on normal thyroid function, are not necessarily spared. In a review article published last year in JAMA Pediatrics, doctors from the Children’s Hospital of Philadelphia pressed primary care doctors to recognize childhood thyroid disease and begin treatment as early as the second week of life to ensure normal development. Hypothyroidism — low hormone levels — in particular is often misdiagnosed, its symptoms resembling those of other diseases or mistaken for “normal” effects of aging. Indeed, the risk of hypothyroidism rises with age. Twenty percent of people over 75, most of them women, lack sufficient levels of thyroid hormone that, among other problems, can cause symptoms of confusion commonly mistaken for dementia. © 2017 The New York Times Company

Keyword: Hormones & Behavior
Link ID: 23866 - Posted: 07.24.2017

Jon Hamilton Professional fighter Gina Mazany practices during a training session at Xtreme Couture Mixed Martial Arts in Las Vegas. She well remembers her first concussion — which came in her first fight. "I was throwing up that night, Mazany says. Bridget Bennett for NPR Gina Mazany grew up in Anchorage, Alaska. And that's where she had her first fight. "It was right after I turned 18," she recalls. A local bar had a boxing ring, and Mazany decided to give it a shot. Her opponent was an older woman with a "mom haircut." "She beat the crap out of me," Mazany says. "Like she didn't knock me out, she didn't finish me. But she just knocked me around for three rounds. And I remember, later that night I was very, very nauseous. I was throwing up that night." It was her first concussion. Concussions are just part of her sport, Mazany figures, but says she tries to protect herself, and to not give anyone else a head injury--at least in training. Bridget Bennett for NPR Thanks to research on boxers and football players, both athletes and the public are becoming more aware of the dangers of sports-related head injuries. Yet there is little data on participants like Mazany. That's because, unlike the vast majority of athletes studied, she is a woman. "We classically have always known the male response to brain injury," says Mark Burns, at Georgetown University. But there have been remarkably few studies of females. The bias runs throughout the scientific literature, even in studies of mice. © 2017 npr

Keyword: Brain Injury/Concussion
Link ID: 23865 - Posted: 07.24.2017

Susan Milius Sonar pings from a hungry bat closing in can inspire hawkmoths to get their genitals trilling. The ultrasonic “eeeee” of scraping moth sex organs may serve as a last-second acoustic defense, says behavioral ecologist Jesse Barber of Boise State University in Idaho. In theory, the right squeak could jam bats’ targeting sonar, remind them of a noisy moth that tasted terrible or just startle them enough for the hawkmoth to escape. Males of at least three hawkmoth species in Malaysia squeak in response to recorded echolocation sounds of the final swoop in a bat attack, Barber and Akito Kawahara of the University of Florida in Gainesville report July 3 in Biology Letters. Female hawkmoths are hard to catch, but the few Barber and Kawahara have tested squeak too. Although they’re the same species as the males, they use their genitals in a different way to make ultrasound. Squeak power may have arisen during courtship and later proved useful during attacks. Until now, researchers knew of only two insect groups that talk back to bats: some tiger moths and tiger beetles. Neither is closely related to hawkmoths, so Barber speculates that anti-bat noises might be widespread among insects. Slowed-down video shows first the male and then the female hawkmoth creating ultrasonic trills at the tips of their abdomens. Males use a pair of claspers that grasp females in mating. To sound off, these quickly slide in and out of the abdomen, rasping specialized scales against the sides. Females rub the left and right sides of their abdominal structures together. J. Barber and A.Y. Kawahara. Hawkmoths produce anti-bat ultrasound. Biology Letters. Posted July 3, 2013. doi: 10.1098/rsbl.2013.0161 [Go to] |© Society for Science & the Public 2000 - 2017.

Keyword: Hearing
Link ID: 23864 - Posted: 07.24.2017

By Sharon Begley, STAT Lab mice whose brains were injected with cells from schizophrenia patients became afraid of strangers, slept fitfully, felt intense anxiety, struggled to remember new things, and showed other signs of the mental disorder, scientists reported on Thursday. The latest advance in “chimeras,” animals created by transplanting cells from one species into another, demonstrated the value of the technique, scientists not involved in the study said, but is likely to draw renewed attention to a controversial field that opponents see as deeply immoral and undermining the natural order. Under a 2015 moratorium, the National Institutes of Health does not fund research that transplants human stem cells into early embryos of other animals. When the NIH asked for public comment on lifting the moratorium, it received nearly 20,000 responses, almost all objecting to “grossly unethical research”; many mentioned Frankenstein. But the new study, in Cell Stem Cell, injected human cells into newborn mice, not embryos. It received funding from the NIH as well as private foundations, to unravel how brain development goes off the rails to cause schizophrenia. Although the prevailing idea has been that the devastating disease, which strikes some 1 percent of U.S. adults, is primarily caused by something going wrong with neurons, the scientists suspected the brain’s support cells, called glia. © 2017 Scientific American,

Keyword: Schizophrenia; Glia
Link ID: 23863 - Posted: 07.22.2017

Joseph Jebelli The terror of Alzheimer’s is that it acts by degrees, and can therefore bewilder family members as much as its victims. Those who first notice the onset of Alzheimer’s in a loved one tell of forgotten names and unsettling behaviour, of car keys found in the fridge and clothing in the kitchen cabinet, of aimless wanderings. Naturally, they want to understand the boundaries of normal ageing and whether these are being crossed. Often, the answer arrives when they’re greeted as complete strangers, when the patient’s mind becomes irrevocably unmoored from its past. The disease is terrifying for its insidiousness as well as its long-term manifestations. Fear partly explains why Alzheimer’s has been ignored for so long. Yet it is now the leading cause of death among the oldest people, and according to Professor Sir Michael Marmot, an expert in health inequalities, it could be an “important part” of the stagnation in increases in life expectancy since 2010 that he has identified. As a researcher, I have been struck by how many patients speak openly about their condition only after receiving a diagnosis. “I knew something wasn’t right. Sometimes I don’t know what day of the week it is or what I have to do,” one newly diagnosed patient told me. “I look in my calendar but then I think: why am I looking at this? My husband was the one who made me see a GP. I was too frightened. I thought I might have it but I didn’t want to hear it.” © 2017 Guardian News and Media Limited

Keyword: Alzheimers
Link ID: 23862 - Posted: 07.22.2017

By Becca Cudmore A mother rat’s care for her pup reaches all the way into her offspring’s DNA. A young rat that gets licked and groomed a lot early on in life exhibits diminished responses to stress thanks to epigenetic changes in the hippocampus, a brain region that helps transform emotional information into memory. Specifically, maternal solicitude reduces DNA methylation and changes the structure of DNA-packaging proteins, triggering an uptick in the recycling of the neurotransmitter serotonin and the upregulation of the glucocorticoid receptor. These changes make the nurtured rat’s brain quicker to sense and tamp down the production of stress hormones in response to jarring experiences such as unexpected sound and light. That pup will likely grow into a calm adult, and two studies have shown that female rats who exhibit a dampened stress response are more likely to generously lick, groom, and nurse their own young. Caring for pups is one example of what casual observers of behavior might call an animal’s instinct—generally considered to be an innate, genetically encoded phenomenon. But could such epigenetic changes, when encoded as ancestral learning, also be at the root of maternal care and other seemingly instinctual behaviors we see across the animal kingdom? “We don’t have a general theory for the mechanics of instinct as we do for learning, and this is something that has troubled me for a very long time,” says University of Illinois entomologist Gene Robinson. He studies social evolution in the Western honey bee and recently coauthored a perspective piece in Science together with neurobiologist Andrew Barron of Macquarie University in Sydney, Australia, suggesting methylation as a possible mechanism for the transgenerational transmission of instinctual behavior, rather than those behaviors being hardwired in the genome (356:26-27, 2017). Robinson and Barron suggest that instinctual traits, such as honey bees’ well-known waggle dance or a bird’s in-born ability to sing its species’ songs, are the result of traits first learned by their ancestors and inherited across generations by the process of methylation. This differs from classical thoughts on animal learning, which say that if a behavior is learned, it is not innate, and will not be inherited. © 1986-2017 The Scientist

Keyword: Epigenetics; Evolution
Link ID: 23861 - Posted: 07.22.2017

By Aylin Woodward See, hear. Our eardrums appear to move to shift our hearing in the same direction as our eyes are looking. Why this happens is unclear, but it may help us work out which objects we see are responsible for the sounds we can hear. Jennifer Groh at Duke University in Durham, North Carolina, and her team have been using microphones inserted into people’s ears to study how their eardrums change during saccades – the movement that occurs when we shift visual focus from one place to another. You won’t notice it, but our eyes go through several saccades a second to take in our surroundings. Examining 16 people, the team detected changes in ear canal pressure that were probably caused by middle-ear muscles tugging on the eardrum. These pressure changes indicate that when we look left, for example, the drum of our left ear gets pulled further into the ear and that of our right ear pushed out, before they both swing back and forth a few times. These changes to the eardrums began as early as 10 milliseconds before the eyes even started to move, and continued for a few tens of milliseconds after the eyes stopped. Making sense “We think that before actual eye movement occurs, the brain sends a signal to the ear to say ‘I have commanded the eyes to move 12 degrees to the right’,” says Groh. The eardrum movements that follow the change in focus may prepare our ears to hear sounds from a particular direction. © Copyright New Scientist Ltd.

Keyword: Hearing; Vision
Link ID: 23860 - Posted: 07.22.2017