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2014 by Andy Coghlan Seeing is definitely believing when it comes to stem cell therapy. A blind man has recovered enough sight to ride his horse. A woman who could see no letters at all on a standard eye test chart can now read the letters on the top four lines. Others have recovered the ability to see colour. All have had injections of specialised retinal cells in their eyes to replace ones lost through age or disease. A trial in 18 people with degenerative eye conditions is being hailed as the most promising yet for a treatment based on human embryonic stem cells. "We've been hearing about their potential for more than a decade, but the results have always been in mice and rats, and no one has shown they're safe or effective in humans long term," says Robert Lanza of Advanced Cell Technology in Marlborough, Massachusetts, the company that carried out the stem cell intervention. "Now, we've shown both that they're safe and that there's a real chance these cells can help people." Ten years ago, the team at Advanced Cell Technology announced that it had successfully converted human embryonic stem cells into retinal pigment epithelial cells. These cells help keep the eyes' light-detecting rods and cones healthy. But when retinal pigment epithelial cells deteriorate, blindness can occur. This happens in age-related macular degeneration and Stargardt's macular dystrophy. In a bid to reverse this, Lanza's team injected retinal cells into one of each of the 18 participants' eyes, half of whom had age-related macular degeneration and half had Stargardt's. A year later, 10 people's eyes had improved, and the eyes of the others had stabilised. Untreated eyes had continued to deteriorate. © Copyright Reed Business Information Ltd.

Keyword: Vision; Aggression
Link ID: 20210 - Posted: 10.16.2014

BY Bethany Brookshire Stress is our coping response. Whether emotional or physical, stress is how organisms react to upheaval in their lives. And in many cases, that response requires tradeoffs. An animal will make it through now, but may come out with fewer fat stores or a shorter life span. But a new study shows that under certain conditions, developmental stress in male zebra finches might have a positive effect, in the form of more offspring to carry on his genes. Ondi Crino, a biologist now at Macquarie University in Sydney, examined how stress during development might affect reproductive success in male zebra finches. She purchased 10 male and 10 female zebra finches from pet shops near the University of Montana. The birds were allowed to pair off and nest. When the first batch of chicks was 12 days old, Crino fed half of the male offspring peanut oil, and half peanut oil with the hormone corticosterone mixed in. Both humans and finches produce stress-related hormones. Humans produce cortisol, while finches produce corticosterone. These two hormones increase during times of stress and cause many of the negative effects we associate with worry and pressure. So administering corticosterone is one method of “stressing” an animal without changing anything else in its environment. The dose was in the range of what a young bird might experience in the midst of a natural upheaval such as a cold snap or famine. After 16 days of the peanut oil supplement, the young male birds receiving corticosterone were smaller than their relaxed counterparts. They also had a larger spike in their own corticosterone levels when they were stressed. But over time, the chicks that received corticosterone appeared to grow out of their stressful upbringing. By adulthood they were the same size as controls, and they did not show frazzled feathers or pale colors that might indicate a rough chickhood. © Society for Science & the Public 2000 - 2014

Keyword: Stress; Aggression
Link ID: 20209 - Posted: 10.16.2014

By Jane E. Brody In the 1997 film “As Good As It Gets,” Jack Nicholson portrays Melvin Udall, a middle-aged man with obsessive-compulsive disorder who avoids stepping on cracks, locks doors and flips light switches exactly five times, and washes his hands repeatedly, each time tossing out the new bar of soap he used. He brings wrapped plastic utensils to the diner where he eats breakfast at the same table every day. Though the film is billed as a romantic comedy, Melvin’s disorder is nothing to laugh about. O.C.D. is often socially, emotionally and vocationally crippling. It can even be fatal. Four years ago, John C. Kelly, 24, killed himself in Irvington, N.Y., after a long battle with a severe form of obsessive-compulsive disorder. Mr. Kelly was a devoted baseball player, and now friends hold an annual softball tournament to raise money for the foundation established in his honor to increase awareness of the disorder. Obsessive thoughts and compulsive behaviors occur in almost every life from time to time. I have a fair share of compulsive patterns: seasonings arranged in strict alphabetical order; kitchen equipment always put back the same way in the same place; two large freezers packed with foods just in case I need them. I hold onto a huge collection of plastic containers, neatly stacked with their covers, and my closets bulge with clothes and shoes I haven’t worn in years, and probably never will again — yet cannot bring myself to give away. But these common habits fall far short of the distressing obsessions and compulsions that are the hallmarks of O.C.D.: intrusive, disturbing thoughts or fears that cannot be ignored and compel the sufferer to engage in ritualistic, irrational behaviors to relieve the resulting anxiety.

Keyword: OCD - Obsessive Compulsive Disorder
Link ID: 20208 - Posted: 10.16.2014

By Josie Gurney-Read, Online Education Editor Myths about the brain and how it functions are being used to justify and promote teaching methods that are essentially “ineffective”, according to new research. The study, published today in Nature Reviews Neuroscience, began by presenting teachers in the UK, Turkey, Greece, China and the Netherlands, with seven myths about the brain and asked them whether they believed the myths to be true. According to the figures, over half of teachers in the UK, the Netherlands and China believe that children are less attentive after sugary drinks and snacks and over a quarter of teachers in the UK and Turkey believe that a pupil’s brain will shrink if they drink fewer than six to eight glasses of water a day. Furthermore, over 90 per cent of teachers in all countries believe that a student will learn better if they receive information in their preferred learning style – auditory, visual, kinaesthetic. This is despite the fact that there is "no convincing evidence to support this theory". Dr Paul Howard-Jones, author of the article from Bristol University’s Graduate School of Education, said that many teaching practices are “sold to teachers as based on neuroscience”. However, he added that, in many cases, these ideas have “no educational value and are often associated with poor practice in the classroom.” The prevalence of many of these “neuromyths” in different countries, could reflect the absence of any teacher training in neuroscience, the research concludes. Dr Howard-Jones warned that this could mean that many teachers are “ill-prepared to be critical of ideas and educational programmes that claim a neuroscientific basis.” © Copyright of Telegraph Media Group Limited 2014

Keyword: Learning & Memory
Link ID: 20207 - Posted: 10.16.2014

By ALEX STONE Smell is one of the oldest human faculties, yet it was one of the last to be understood by scientists. It was not until the early 1990s that biologists first described the inner workings of olfactory receptors — the chemical sensors in our noses — in a discovery that won a Nobel Prize. Since then, the plot has thickened. Over the last decade or so, scientists have discovered that odor receptors are not solely confined to the nose, but found throughout body — in the liver, the heart, the kidneys and even sperm — where they play a pivotal role in a host of physiological functions. Now, a team of biologists at Ruhr University Bochum in Germany has found that our skin is bristling with olfactory receptors. “More than 15 of the olfactory receptors that exist in the nose are also found in human skin cells,” said the lead researcher, Dr. Hanns Hatt. Not only that, but exposing one of these receptors (colorfully named OR2AT4) to a synthetic sandalwood odor known as Sandalore sets off a cascade of molecular signals that appears to induce healing in injured tissue. In a series of human tests, skin abrasions healed 30 percent faster in the presence of Sandalore, a finding the scientists think could lead to cosmetic products for aging skin and to new treatments to promote recovery after physical trauma. The presence of scent receptors outside the nose may seem odd at first, but as Dr. Hatt and others have observed, odor receptors are among the most evolutionarily ancient chemical sensors in the body, capable of detecting a multitude of compounds, not solely those drifting through the air. “If you think of olfactory receptors as specialized chemical detectors, instead of as receptors in your nose that detect smell, then it makes a lot of sense for them to be in other places,” said Jennifer Pluznick, an assistant professor of physiology at Johns Hopkins University who in 2009 found that olfactory receptors help control metabolic function and regulate blood pressure in the kidneys of mice. © 2014 The New York Times Company

Keyword: Chemical Senses (Smell & Taste)
Link ID: 20206 - Posted: 10.14.2014

|By Jenni Laidman During the second and third trimester of pregnancy, the outer layer of the embryo's brain, the cortex, assembles itself into six distinct layers. But in autism, according to new research, this organization goes awry—marring parts of the brain associated with the abilities often impaired in the disorder, such as social skills and language development. Eric Courchesne, director of the Autism Center of Excellence at the University of California, San Diego, and his colleagues uncovered this developmental misstep in a small study that compared 11 brains of children with autism who died at ages two through 15 with 11 brains of kids who died without the diagnosis. The study employed a sophisticated genetic technique that looked for signatures of the activity of 25 genes in brain slices taken from the front of the brain—an area called the prefrontal cortex—as well as from the occipital cortex at the back of the brain and the temporal cortex near the temple. The researchers found disorganized patches, roughly a quarter of an inch across, in which gene expression indicated cells were not where they were supposed to be, amid the folds of tissue in the prefrontal cortex in 10 of 11 brains from children with autism. That part of the brain is associated with higher-order communication and social interactions. The team also found messy patches in the temporal cortices of autistic brains but no disorder at the back of the brain, which also matches typical symptom profiles. The patches appeared at seemingly random locations within the frontal and temporal cortices, which may help explain why symptoms can differ dramatically among individuals, says Rich Stoner, then at U.C. San Diego and the first author of the study, which appeared in the New England Journal of Medicine. © 2014 Scientific American

Keyword: Autism; Aggression
Link ID: 20205 - Posted: 10.14.2014

By JOSHUA A. KRISCH An old stucco house stands atop a grassy hill overlooking the Long Island Sound. Less than a mile down the road, the renowned Cold Spring Harbor Laboratory bustles with more than 600 researchers and technicians, regularly producing breakthroughs in genetics, cancer and neuroscience. But that old house, now a private residence on the outskirts of town, once held a facility whose very name evokes dark memories: the Eugenics Record Office. In its heyday, the office was the premier scientific enterprise at Cold Spring Harbor. There, bigoted scientists applied rudimentary genetics to singling out supposedly superior races and degrading minorities. By the mid-1920s, the office had become the center of the eugenics movement in America. Today, all that remains of it are files and photographs — reams of discredited research that once shaped anti-immigration laws, spurred forced-sterilization campaigns and barred refugees from entering Ellis Island. Now, historians and artists at New York University are bringing the eugenics office back into the public eye. “Haunted Files: The Eugenics Record Office,” a new exhibit at the university’s Asian/Pacific/American Institute, transports visitors to 1924, the height of the eugenics movement in the United States. Inside a dimly lit room, the sounds of an old typewriter click and clack, a teakettle whistles and papers shuffle. The office’s original file cabinets loom over reproduced desks and period knickknacks. Creaky cabinets slide open, and visitors are encouraged to thumb through copies of pseudoscientific papers. © 2014 The New York Times Company

Keyword: Genes & Behavior
Link ID: 20204 - Posted: 10.14.2014

By GINA KOLATA For the first time, and to the astonishment of many of their colleagues, researchers created what they call Alzheimer’s in a Dish — a petri dish with human brain cells that develop the telltale structures of Alzheimer’s disease. In doing so, they resolved a longstanding problem of how to study Alzheimer’s and search for drugs to treat it; the best they had until now were mice that developed an imperfect form of the disease. The key to their success, said the lead researcher, Rudolph E. Tanzi of Massachusetts General Hospital in Boston, was a suggestion by his colleague Doo Yeon Kim to grow human brain cells in a gel, where they formed networks as in an actual brain. They gave the neurons genes for Alzheimer’s disease. Within weeks they saw the hard Brillo-like clumps known as plaques and then the twisted spaghetti-like coils known as tangles — the defining features of Alzheimer’s disease. The work, which also offers strong support for an old idea about how the disease progresses, was published in Nature on Sunday. Leading researchers said it should have a big effect. “It is a giant step forward for the field,” said Dr. P. Murali Doraiswamy, an Alzheimer’s researcher at Duke University. “It could dramatically accelerate testing of new drug candidates.” Of course, a petri dish is not a brain, and the petri dish system lacks certain crucial components, like immune system cells, that appear to contribute to the devastation once Alzheimer’s gets started. But it allows researchers to quickly, cheaply and easily test drugs that might stop the process in the first place. The crucial step, of course, will be to see if drugs that work in this system stop Alzheimer’s in patients. © 2014 The New York Times Company

Keyword: Alzheimers
Link ID: 20203 - Posted: 10.13.2014

Daniel Cressey Mirrors are often used to elicit aggression in animal behavioural studies, with the assumption being that creatures unable to recognize themselves will react as if encountering a rival. But research suggests that such work may simply reflect what scientists expect to see, and not actual aggression. For most people, looking in a mirror does not trigger a bout of snarling hostility at the face staring back. But many animals do seem to react aggressively to their mirror image, and for years mirrors have been used to trigger such responses for behavioural research on species ranging from birds to fish. “There’s been a very long history of using a mirror as it’s just so handy,” says Robert Elwood, an animal-behaviour researcher at Queen’s University in Belfast, UK. Using a mirror radically simplifies aggression experiments, cutting down the number of animals required and providing the animal being observed with an ‘opponent’ perfectly matched in terms of size and weight. But in a study just published in Animal Behaviour1, Elwood and his team add to evidence that many mirror studies are flawed. The researchers looked at how convict cichlid fish (Amatitlania nigrofasciata) reacted both to mirrors and to real fish of their own species. This species prefers to display their right side in aggression displays, which means that they end up alongside each other in a head-to-tail configuration. It is impossible for a fish to achieve this with their own reflection, but Elwood reasoned that fish faced with a mirror would attempt it, and flip from side to side as they tried to present an aggressive display. On the other hand, if the reflection did not trigger an aggressive reaction, the fish would not display such behaviour as much or as frequently. © 2014 Nature Publishing Group,

Keyword: Consciousness; Aggression
Link ID: 20202 - Posted: 10.13.2014

By David Leonhardt and Amanda Cox Like so many other parts of health care, childbirth has become a more medically intense experience over the last two decades. The use of drugs to induce labor has become far more common, as have cesarean sections. Today, about half of all births in this country are hastened either by drugs or surgery, double the share in 1990. Crucial to the change has been a widely held belief that once fetuses pass a certain set of thresholds — often 39 weeks of gestation and five and a half pounds in weight — they’re as healthy as they can get. More time in the womb doesn’t do them much good, according to this thinking. For parents and doctors, meanwhile, scheduling a birth, rather than waiting for its random arrival, is clearly more convenient. But a huge new set of data, based on every child born in Florida over an 11-year span, is calling into question some of the most basic assumptions of our medicalized approach to childbirth. The results also play into a larger issue: the growing sense among many doctors and other experts that Americans would actually be healthier if our health care system were sometimes less aggressive. The new data suggest that the thresholds to maximize a child’s health seem to be higher, which means that many fetuses might benefit by staying longer in the womb, where they typically add at least a quarter-pound per week. Seven-pound babies appear to be healthier than six-pound babies — and to fare better in school as they age. The same goes for eight-pound babies compared with seven-pound babies, and nine-pound babies compared with eight-pound babies. Weight, of course, may partly be an indicator of broader fetal health, but it seems to be a meaningful one: The chunkier the baby, the better it does on average, all the way up to almost 10 pounds. “Birth weight matters, and it matters for everyone,” says David N. Figlio, a Northwestern University professor and co-author of the study, which will soon be published in the American Economic Review, one of the field’s top journals. © 2014 The New York Times Company

Keyword: Development of the Brain; Aggression
Link ID: 20201 - Posted: 10.13.2014

By MOISES VELASQUEZ-MANOFF WHEN Andre H. Lagrange, a neurologist at Vanderbilt University in Nashville, saw the ominous white spots on the patient’s brain scan, he considered infection or lymphoma, a type of cancer. But tests ruled out both. Meanwhile, anti-epilepsy drugs failed to halt the man’s seizures. Stumped, Dr. Lagrange turned to something the mother of the 30-year-old man kept repeating. The fits coincided, she insisted, with spells of constipation and diarrhea. That, along with an odd rash, prompted Dr. Lagrange to think beyond the brain. Antibody tests, followed by an intestinal biopsy, indicated celiac disease, an autoimmune disorder of the gut triggered by the gluten proteins in wheat and other grains. Once on a gluten-free diet, the man’s seizures stopped; those brain lesions gradually disappeared. He made a “nearly complete recovery,” Dr. Lagrange told me. I began encountering case descriptions like this some years ago as I researched autoimmune disease. The first few seemed like random noise in an already nebulous field. But as I amassed more — describing seizures, hallucinations, psychotic breaks and even, in one published case, what looked like regressive autism, all ultimately associated with celiac disease — they began to seem less like anomalies, and more like a frontier in celiac research. They tended to follow a similar plot. What looked like neurological or psychiatric symptoms appeared suddenly. The physician ran through a diagnostic checklist without success. Drugs directed at the brain failed. Some clue suggestive of celiac disease was observed. The diagnosis was made. And the patient recovered on a gluten-free diet. The cases highlighted, in an unusually concrete fashion, the so-called gut-brain axis. The supposed link between the intestinal tract and the central nervous system is much discussed in science journals, often in the context of the microbial community inhabiting the gut. But it’s unclear how, really, we can leverage the link to improve health. © 2014 The New York Times Company

Keyword: Neuroimmunology
Link ID: 20200 - Posted: 10.13.2014

Ann Robinson Neuroscience research got a huge boost last week with news of Professor John O’Keefe’s Nobel prize for work on the “brain’s internal GPS system”. It is an exciting new part of the giant jigsaw puzzle of our brain and how it functions. But how does cutting-edge neuroscience research translate into practical advice about how to pass exams, remember names, tot up household bills and find where the hell you left the car in a crowded car park? O’Keefe’s prize was awarded jointly with Swedish husband and wife team Edvard and May-Britt Moser for their discovery of “place and grid cells” that allow rats to chart where they are. When rats run through a new environment, these cells show increased activity. The same activity happens much faster while the rats are asleep, as they replay the new route. We already knew that the part of the brain known as the hippocampus was involved in spatial awareness in birds and mammals, and this latest work on place cells sheds more light on how we know where we are and where we’re going. In 2000, researchers at University College London led by Dr Eleanor Maguire showed that London taxi drivers develop a pumped-up hippocampus after years of doing the knowledge and navigating the backstreets of the city. MRI scans showed that cabbies start off with bigger hippocampuses than average, and that the area gets bigger the longer they do the job. As driver David Cohen said at the time to BBC News: “I never noticed part of my brain growing – it makes you wonder what happened to the rest of it!” © 2014 Guardian News and Media Limited

Keyword: Learning & Memory; Aggression
Link ID: 20199 - Posted: 10.13.2014

By Meredith Levine, Word went round Janice Mackay's quiet neighbourhood that she was hitting the bottle hard. She'd been seen more than once weaving along the sidewalk in front of her suburban home in Pickering, just outside Toronto, in a sad, drunken stagger. But Mackay wasn't drunk. As it turned out, her inner ear, the body's balance centre, had been destroyed by medication when she was hospitalized for over a month back in May 2005. At the time, Mackay was diagnosed with a life-threatening infection in one of her ovaries, and so was put on a cocktail of medication, including an IV drip of gentamicin, a well-known, inexpensive antibiotic that is one of the few that hasn't fallen prey to antibiotic-resistant bacteria. A few weeks later, the infection was almost gone when Mackay, still hospitalized, suddenly developed the bed spins and vomiting. Her medical team told her she'd been laying down too long and gave her Gravol, but the symptoms didn't go away. In a follow-up appointment after her discharge, Mackay was told that the dizziness was a side effect of the gentamicin, and that she would probably have to get used to it. But she didn't discover the extent of the damage until later when neurotologist Dr. John Rutka assessed her condition and concluded that the gentamicin had essentially destroyed her vestibular system, the body's motion detector, located deep within the inner ear. © CBC 2014

Keyword: Hearing
Link ID: 20198 - Posted: 10.13.2014

By CATHERINE SAINT LOUIS Many cases of so-called crib death, about one in eight, occur among infants who have been placed on sofas, researchers reported on Monday. Dr. Jeffrey Colvin, a pediatrician at Children’s Mercy Hospital in Kansas City, Mo., and his colleagues analyzed data on 7,934 sudden infant deaths in 24 states, comparing those that occurred on sofas with those in cribs, bassinets or beds. Previous research had shown that couches were particularly hazardous for infants. The new analysis, published in the journal Pediatrics, tried to identify factors significant in these deaths. “It’s not only one risk that’s higher relative to other sleep environments,” said Barbara Ostfeld, a professor of pediatrics at Rutgers Robert Wood Johnson Medical School who was not involved in the new study. “It’s multiple risks.” Nearly three-quarters of the deaths occurred among infants age 3 months or younger, the researchers found. Pediatricians have long advised putting infants to sleep only on their backs, alone and on a firm, flat surface without a pillow. The new study found parents were more likely to lay their infants face down on a sofa than, for instance, face down in a crib. There’s a “fallacy that if I’m awake or watching, SIDS won’t happen,” Dr. Colvin said, referring to sudden infant death syndrome. © 2014 The New York Times Company

Keyword: Sleep; Aggression
Link ID: 20197 - Posted: 10.13.2014

By MICHAEL S. A. GRAZIANO OF the three most fundamental scientific questions about the human condition, two have been answered. First, what is our relationship to the rest of the universe? Copernicus answered that one. We’re not at the center. We’re a speck in a large place. Second, what is our relationship to the diversity of life? Darwin answered that one. Biologically speaking, we’re not a special act of creation. We’re a twig on the tree of evolution. Third, what is the relationship between our minds and the physical world? Here, we don’t have a settled answer. We know something about the body and brain, but what about the subjective life inside? Consider that a computer, if hooked up to a camera, can process information about the wavelength of light and determine that grass is green. But we humans also experience the greenness. We have an awareness of information we process. What is this mysterious aspect of ourselves? Many theories have been proposed, but none has passed scientific muster. I believe a major change in our perspective on consciousness may be necessary, a shift from a credulous and egocentric viewpoint to a skeptical and slightly disconcerting one: namely, that we don’t actually have inner feelings in the way most of us think we do. Imagine a group of scholars in the early 17th century, debating the process that purifies white light and rids it of all colors. They’ll never arrive at a scientific answer. Why? Because despite appearances, white is not pure. It’s a mixture of colors of the visible spectrum, as Newton later discovered. The scholars are working with a faulty assumption that comes courtesy of the brain’s visual system. The scientific truth about white (i.e., that it is not pure) differs from how the brain reconstructs it. © 2014 The New York Times Company

Keyword: Consciousness
Link ID: 20196 - Posted: 10.11.2014

By Melissa Hogenboom Science reporter, BBC News A small group of neurons that respond to the hormone oxytocin are key to controlling sexual behaviour in mice, a team has discovered. The researchers switched off these cells which meant they were no longer receptive to oxytocin. This "love hormone" is already known to be important for many intimate social situations. Without it, female mice were no more attracted to a mate than to a block of Lego, the team report in journal Cell. These neurons are situated in the prefrontal cortex, an area of the brain important for personality, learning and social behaviour. Both when the hormone was withheld and when the cells were silenced, the females lost interest in mating during oestrous, which is when female mice are sexually active. At other times in their cycle they responded to the males with normal social behaviour. The results were "pretty fascinating because it was a small population of cells that had such a specific effect", said co-author of the work Nathaniel Heintz of the Rockefeller University in New York. "This internal hormone gets regulated in many different contexts; in this particular context, it works through the prefrontal cortex to help modulate social and sexual behaviour in female mice. "It doesn't mean it's uniquely responsible because the hormone acts in several important places in the brain but it does show that this particular cell type is required for this aspect of female social behaviour," Dr Heintz told BBC News. To silence the neurons, the team used toxins that block the ability of the cells to transmit signals to other neurons - technology that has recently revolutionised the ability to study small populations of neurons. BBC © 2014

Keyword: Sexual Behavior; Aggression
Link ID: 20195 - Posted: 10.11.2014

by Mallory Locklear Do you have an annoying friend who loves bungee jumping or hang-gliding, and is always blathering on about how it never scares them? Rather than being a macho front, their bravado may have a biological basis. Research from Stony Brook University in New York shows that not all risk-takers are cut from the same cloth. Some actually seem to feel no fear – or at least their bodies and brains don't respond to danger in the usual way. The study is the first to attempt to tease apart the differences in the risk-taking population. In order to ensure every participant was a card-carrying risk-taker, the team led by Lilianne Mujica-Parodi, recruited 30 first-time skydivers. "Most studies on sensation-seeking compare people who take risks and people who don't. We were interested in something more subtle – those who take risks adaptively and those who do so maladaptively." In other words, do all risk-takers process potential danger in the same way or do some ignore the risks more than others? To find out, the researchers got their participants to complete several personality questionnaires, including one that asked them to rank how well statements such as, "The greater the risk the more fun the activity," described them. Next, the team used fMRI imaging to observe whether the participants' corticolimbic brain circuit – which is involved in risk assessment - was well-regulated. A well-regulated circuit is one that reacts to a threat and then returns to a normal state afterwards. © Copyright Reed Business Information Ltd

Keyword: Emotions; Aggression
Link ID: 20194 - Posted: 10.11.2014

By Carl T. Hall Even Clayton Kershaw, the Los Angeles Dodgers’ pitching ace, makes mistakes now and then. And although very few of his mistakes seemed to do Giants hitters much good this season, a team of San Francisco scientists found a way to take full advantage. A new study by UCSF researchers revealed a tendency of the brain’s motion-control system to run off track in a predictable way when we try to perform the same practiced movement over and over. The scientists found the phenomenon first in macaque monkeys, then documented exactly the same thing in Kershaw’s game video. Although he struggled in a playoff appearance last week, the left-hander’s pitching performance during the regular season was among the best on record. It included a minuscule 1.77 earned run average, a nearly flawless no-hitter in June, 239 strikeouts and only 31 walks. He led the major leagues with 10.85 strikeouts per nine innings pitched. In what turned out to be an early warm-up to the playoffs, UCSF scientists Kris Chaisanguanthum, Helen Shen and Philip Sabes delved into the motor-control system of the primate brain. Their study, published in the Journal of Neuroscience, could help design better prosthetic limbs — or make robots that move less like robots and more like Kershaw. Unlike most machines, our brains seem to never stop trying to adapt to new information, making subtle adjustments each time we repeat a particular movement no matter how practiced. This trial-by-trial form of learning has obvious advantages in a fast-changing world, but also seems prone to drift away from spot-on accuracy as those small adjustments go too far.

Keyword: Learning & Memory
Link ID: 20193 - Posted: 10.11.2014

By David Shultz The next time you see a fruit fly hovering around your pint of beer, don’t swat it—appreciate it. You’re witnessing a unique relationship between yeast and insect. A new study reveals that the single-celled organisms have evolved to secrete a fruity scent that attracts fruit flies, which they hitch a ride on for greener pastures. The findings may also explain the sweet aroma of some craft beers. Like many scientific discoveries, the new work was the product of a happy accident. Kevin Verstrepen, a geneticist at KU Leuven in Belgium, was working with two types of yeast: a normal strain and another with a mutation in a gene called ATF1 that causes the cells to produce fewer odors during fermentation. “Nobody really knew what was happening until I was lazy enough to leave the lab on a Friday with these yeast left out on the bench,” he says. By coincidence, a group of fruit flies (Drosophila melanogaster) chose that weekend to escape from a neighboring genetics lab. When Verstrepen returned to work on Monday, he discovered that the insects had found their way into the smelly yeast culture but had ignored the mutant colony. To probe further, Verstrepen and colleagues set up an enclosed “arena” and pumped ATF1 aromas, which are either fruity, flowery, or solventlike, into one corner. Another corner received a dose of odors from the ATF1-deficient yeast. The remaining two corners emitted odorless streams of air to serve as controls. As expected, the flies congregated almost exclusively in the corner emitting the fragrant odors of yeast with intact ATF1 genes. Analyses of the insects’ brains revealed that the neurons in flies exposed to smelly yeast responded in an entirely different way from those exposed to odorless air or the scent of ATF1-deficient yeast strain, the researchers report online today in Cell Reports. © 2014 American Association for the Advancement of Science

Keyword: Chemical Senses (Smell & Taste)
Link ID: 20192 - Posted: 10.11.2014

For decades, scientists thought that neurons in the brain were born only during the early development period and could not be replenished. More recently, however, they discovered cells with the ability to divide and turn into new neurons in specific brain regions. The function of these neuroprogenitor cells remains an intense area of research. Scientists at the National Institutes of Health (NIH) report that newly formed brain cells in the mouse olfactory system — the area that processes smells — play a critical role in maintaining proper connections. The results were published in the October 8 issue of the Journal of Neuroscience. “This is a surprising new role for brain stem cells and changes the way we view them,” said Leonardo Belluscio, Ph.D., a scientist at NIH’s National Institute of Neurological Disorders and Stroke (NINDS) and lead author of the study. The olfactory bulb is located in the front of the brain and receives information directly from the nose about odors in the environment. Neurons in the olfactory bulb sort that information and relay the signals to the rest of the brain, at which point we become aware of the smells we are experiencing. Olfactory loss is often an early symptom in a variety of neurological disorders, including Alzheimer’s and Parkinson’s diseases. In a process known as neurogenesis, adult-born neuroprogenitor cells are generated in the subventricular zone deep in the brain and migrate to the olfactory bulb where they assume their final positions. Once in place, they form connections with existing cells and are incorporated into the circuitry.

Keyword: Chemical Senses (Smell & Taste); Aggression
Link ID: 20191 - Posted: 10.11.2014