By Bruce Bower NEW YORK CITY — Psychiatrists regularly get criticized for turning typical life problems into medical disorders. But in an odd reversal, many mental health clinicians are trying to transform one certified mental illness, borderline personality disorder, into a label for needy, manipulative people who don’t need treatment, a sociologist reported at the American Sociological Association’s annual meeting on August 11. Patients with borderline personality disorder, unlike people with schizophrenia or other serious mental conditions, are often viewed by mental health providers as having cynically planned out rash acts and even suicide attempts, sociologist Sandra Sulzer of the University of North Carolina at Chapel Hill found in extensive interviews with 22 psychiatrists and psychologists in the United States. The condition includes difficulty controlling emotions, intense but unstable relationships, recklessness, cutting and other acts of self-harm, along with attempted and completed suicides. Before Sulzer’s study, little was known about how mental health professionals discuss and deal with this troubling set of symptoms. “Clinicians frequently view borderline personality disorder symptoms as signs of badness, not sickness, and as a code to route patients out of mental health care,” Sulzer said. That finding goes a long way toward explaining why many borderline personality disorder patients receive no treatment despite the availability of effective forms of psychotherapy (SN: 6/16/07, p. 374), she suggested. © Society for Science & the Public 2000 - 2013

Keyword: Emotions
Link ID: 18511 - Posted: 08.15.2013

Maggie Fox NBC News A 12-year-old Arkansas girl infected with a brain-eating amoeba is on the mend and may be only the third person known to have survived the baffling infection, doctors said Wednesday. She’s recovering just as a 12-year-old boy in Miami struggles for his life with the same infection. Doctors note the infection is still extremely rare – so rare that health officials don’t know how to track it or protect against it. They’re also not sure why Kali Hardig of Little Rock appears to be recovering, but federal health officials are relaying details about her treatment to the team treating Zachary Reyna in Miami. The amoeba is called Naegleria fowleri, and it’s found in warm, fresh waters all over the world. It’s been seen in hot springs and swimming holes, freshwater lakes and even in neti pots used to clean out sinuses. It infects people through the nose, traveling up the nerve cells that carry smell signals into the brain. Doctors are not sure how or why a very few people are susceptible, but it’s clear that having water forced up into the sinuses, perhaps by dunking or diving, is an important factor. Kali became ill after swimming at a water park fed by spring water in Little Rock. Doctors at Arkansas Children’s Hospital tried the standard approach – a cocktail of four antibiotics – but also used an experimental antifungal drug and an unusual approach that involved lowering her body temperature.

Keyword: Neuroimmunology; Development of the Brain
Link ID: 18510 - Posted: 08.15.2013

Brian Owens Too much sugar is bad for you, but how much, exactly, is too much? A study in mice has found that the animals' health and ability to compete can be harmed by a diet that has sugar levels equivalent to what many people in the United States currently consume. High-sugar diets are associated not only with obesity and diabetes, but also with other human conditions such as coronary heart disease. However, the exact causal links for many of these has not been established. When studies are done in mice to evaluate health effects of sugar, the doses given are often so high, and outside the range of equivalent human consumption, that it is hard to tell conclusively whether the results are relevant to people. “Nobody has been able to show adverse effects at human-relevant levels,” says Wayne Potts, an evolutionary biologist at the University of Utah in Salt Lake City. But in a study published today in Nature Communications1, Potts and his colleagues looked at what happens under conditions comparable to the lifestyles of a substantial number of people in the United States. The researchers bred a pair of wild mice captured by Potts in a bakery, and fed offspring a diet in which 25% of the calories came from sugar. This is the maximum 'safe' level recommended by the US National Academies and by the US Department of Agriculture, and such a diet is consumed by around 13–25% of the US population. The safe level is roughly equivalent to drinking three cans of sugary drinks a day but having an otherwise sugar-free diet. © 2013 Nature Publishing Group

Keyword: Obesity
Link ID: 18509 - Posted: 08.14.2013

By KATIE THOMAS The first test for a new sleep drug is — unsurprisingly — how safely it puts people to sleep. Now comes a second test: how safely it lets people wake up. The Food and Drug Administration is taking heightened interest in the issue, as new evidence suggests what many people have long suspected: the effects of common prescription sleep aids like Ambien can persist well into the next day. Of particular concern is whether people who take the drugs before bed can drive safely the next morning. Consumer advocates have warned for years about possible links between sleep drugs and car accidents. In one prominent example, Kerry Kennedy, the former wife of Gov. Andrew M. Cuomo, was arrested last year after tests showed she had taken a sleep aid before swerving her car into a tractor-trailer. The F.D.A.’s actions are part of a robust national conversation about how to cope with the throngs of drivers who take to roads every day under the influence of prescription drugs. Law enforcement authorities have struggled with how to prosecute those who are impaired, especially when they have a prescription. A government survey in 2007 found that nearly 5 percent of daytime drivers tested positive for prescription or over-the-counter medications. Doctors wrote close to 60 million prescriptions for sleep aids in the United States last year, according to the research firm IMS Health, but experts say testing how these drugs affect driving is not easy. Nonetheless, the F.D.A. has been unusually active. Last month, it rejected an application by Merck to approve a new sleep drug, suvorexant, in part because tests showed that some people had trouble driving the next day. In May, the agency warned patients taking common allergy drugs like Benadryl against driving, noting that the sedating effects can sometimes last into the following day. In January, citing similar concerns, the F.D.A. took the unusual step of requiring that all manufacturers of zolpidem, the generic name of Ambien, cut in half the dosage for women. © 2013 The New York Times Company

Keyword: Sleep; Attention
Link ID: 18508 - Posted: 08.14.2013

By Laura Sanders Seeing people of different races early in life may sculpt the developing brain, a new study suggests. Children who spent infancy in Chinese or Russian orphanages with little contact from outsiders had difficulty perceiving emotions on faces of people of unfamiliar races. These children also showed heightened brain responses to faces of unfamiliar races. “This new study is unique in that it for the first time tells us that early exposure to faces of different races is important,” says psychologist Kang Lee of the University of Toronto. “The lack of such exposure can have long-lasting effects.” Although the results, published in the Aug. 14 Journal of Neuroscience, suggest that race shapes the brain during infancy, the study can’t say what such a brain change might mean, says study coauthor Eva Telzer of the University of Illinois at Urbana-Champaign. “Our findings do not say anything about children’s behavior in their daily life.” Telzer and her colleagues studied one of the few populations that could help reveal these effects: orphans who the researchers believe lived amid a single race of people early in life. Most of these 36 children spent time in Russian or Chinese orphanages and were later adopted by American families of European descent. On average, the kids were adopted when they were 2 to 3 years old and were between 6 and 16 years old at the time of the study. © Society for Science & the Public 2000 - 2013

Keyword: Development of the Brain; Attention
Link ID: 18507 - Posted: 08.14.2013

by Sara Reardon It's a case of hear no object, see no object. Hearing the name of an object appears to influence whether or not we see it, suggesting that hearing and vision might be even more intertwined than previously thought. Studies of how the brain files away concepts suggest that words and images are tightly coupled. What is not clear, says Gary Lupyan of the University of Wisconsin in Madison, is whether language and vision work together to help you interpret what you're seeing, or whether words can actually change what you see. Lupyan and Emily Ward of Yale University used a technique called continuous flash suppression (CFS) on 20 volunteers to test whether a spoken prompt could make them detect an image that they were not consciously aware they were seeing. CFS works by displaying different images to the right and left eyes: one eye might be shown a simple shape or an animal, for example, while the other is shown visual "noise" in the form of bright, randomly flickering shapes. The noise monopolises the brain, leaving so little processing power for the other image that the person does not consciously register it, making it effectively invisible. Wheels of perception In a series of CFS experiments, the researchers asked volunteers whether or not they could see a specific object, such as a dog. Sometimes it was displayed, sometimes not. When it was not displayed or when the image was of another animal such as a zebra or kangaroo, the volunteers typically reported seeing nothing. But when a dog was displayed and the question mentioned a dog, the volunteers were significantly more likely to become aware of it. "If you hear a word, that greases the wheels of perception," says Lupyan: the visual system becomes primed for anything to do with dogs. © Copyright Reed Business Information Ltd.

Keyword: Vision; Attention
Link ID: 18506 - Posted: 08.14.2013

By Michelle Roberts Health editor, BBC News online Brain scans may allow detection of dyslexia in pre-school children even before they start to read, say researchers. A US team found tell-tale signs on scans that have already been seen in adults with the condition. And these brain differences could be a cause rather than a consequence of dyslexia - something unknown until now - the Journal of Neuroscience reports. Scans could allow early diagnosis and intervention, experts hope. The part of the brain affected is called the arcuate fasciculus. Among the 40 school-entry children they studied they found some had shrinkage of this brain region, which processes word sounds and language. They asked the same children to do several different types of pre-reading tests, such as trying out different sounds in words. Those children with a smaller arcuate fasciculus had lower scores. It is too early to say if the structural brain differences found in the study are a marker of dyslexia. The researchers plan to follow up groups of children as they progress through school to determine this. Lead researcher Prof John Gabrieli said: "We don't know yet how it plays out over time, and that's the big question. BBC © 2013

Keyword: Dyslexia; Brain imaging
Link ID: 18505 - Posted: 08.14.2013

by Simon Makin Autism may shape the brains of women differently to those of men. The condition seems to cause female, but not male, brains to look more masculine, suggesting that one controversial view of autism – as an extreme version of the male brain – may need rethinking. Simon Baron-Cohen at the Autism Research Centre in Cambridge, UK, has previously found that men tend to be better at systematising tasks and females better at ones involving empathising. As people with autism tend to be good systematisers and below-average empathisers, he has argued that autism may be an extreme version of the male brain, or EMB. However, the theory is contentious. "The jury is still out," says autism researcher Uta Frith of University College London. That's partly because of the difficulty in pinning down the source of the gender differences. "It's far from clear which male-female differences are biological and which are cultural," says developmental psychologist Caspar Addyman, of the Birkbeck Babylab at the University of London. In their latest study, Baron-Cohen's team used MRI scans to look for differences in the volume of brain regions in 120 adults, split into four equal groups – men and women, with and without autism. The researchers first compared the brains of males with and without autism, then did the same for female brains. They then compared these two differences. "If autism manifests the same in both genders, these two differences should be alike," says Baron-Cohen's colleague at the Autism Research Centre Meng-Chuan Lai, "but if not, they should be different – and this is what we found." © Copyright Reed Business Information Ltd.

Keyword: Autism; Sexual Behavior
Link ID: 18504 - Posted: 08.14.2013

The Associated Press The biggest study of its kind suggests autism might be linked with inducing and speeding up labour, preliminary findings that need investigating since labour is induced in increasing numbers of U.S. women, the authors and other autism experts say. It's possible that labour-inducing drugs might increase the risk — or that the problems that lead doctors to start labour explain the results. These include mothers' diabetes and fetal complications, which have previously been linked with autism. There is a growing consensus that risks for autism occur before birth or soon after.There is a growing consensus that risks for autism occur before birth or soon after. (Veejay Villafranca/Getty ) Like most research into autism causes, the study doesn't provide conclusive answers, and the authors say the results shouldn't lead doctors to avoid inducing labour or speeding it up since it can be life-saving for mothers and babies. Simon Gregory, lead author and an associate professor of medicine and medical genetics at Duke University, emphasized, "We haven't found a connection for cause and effect. One of the things we need to look at is why they were being induced in the first place." Government data suggest 1 in 5 U.S. women have labour induced — twice as many as in 1990. Smaller studies suggested a possible tie between induced labour and autism, but the new research is the largest to date, involving more than 600,000 births. The government-funded study was published online Monday in JAMA Pediatrics. © CBC 2013

Keyword: Autism; Hormones & Behavior
Link ID: 18503 - Posted: 08.14.2013

By John von Radowitz TARGETING poor housekeeping in cells could lead to new treatments for Parkinson's disease, scientists believe. Research has linked the disease to a genetic defect that stops cells clearing out defective mitochondria, tiny metabolic generators that supply energy. Dysfunctional mitochondria are potentially very harmful. Cells normally dispose of them through a "hazardous waste" management system called mitophagy that causes the bean-like bodies to be digested and broken down. Scientists have now discovered a biological pathway that allows mutations in a gene called FBxo7 to interfere with mitophagy. In people with Parkinson's, this leads to a build-up of defective mitochondria that may result in the death of brain cells. The study, published in the journal Nature Neuroscience, indicates that mitophagy might be the key to new treatment options for the disease. Dr Helene Plun-Favreau, one of the researchers from the University College London Institute of Neurology, said: "These findings suggest that treatment strategies that target mitophagy might be developed to benefit patients with Parkinson's disease in the future. "What makes the study so robust is the confirmation of defective mitophagy in a number of different Parkinson's models, including cells of patients who carry a mutation in the Fbxo7 gene." News Ltd 2013 Copyright

Keyword: Parkinsons
Link ID: 18502 - Posted: 08.14.2013

What people experience as death creeps in—after the heart stops and the brain becomes starved of oxygen—seems to lie beyond the reach of science. But the authors of a new study on dying rats make a bold claim: After cardiac arrest, the rodents’ brains enter a state similar to heightened consciousness in humans. The researchers suggest that if the same is true for people, such brain activity could be the source of the visions and other sensations that make up so-called near-death experiences. Estimated to occur in about 20% of patients who survive cardiac arrest, near-death experiences are frequently described as hypervivid or “realer-than-real,” and often include leaving the body and observing oneself from outside, or seeing a bright light. The similarities between these reports are hard to ignore, but the conversation about near-death experiences often bleeds into metaphysics: Are these visions produced solely by the brain, or are they a glimpse at an afterlife outside the body? Neurologist Jimo Borjigin of the University of Michigan, Ann Arbor, got interested in near-death experiences during a different project—measuring the hormone levels in the brains of rodents after a stroke. Some of the animals in her lab died unexpectedly, and her measurements captured a surge in neurochemicals at the moment of their death. Previous research in rodents and humans has shown that electrical activity surges in the brain right after the heart stops, then goes flat after a few seconds. Without any evidence that this final blip contains meaningful brain activity, Borjigin says “it’s perhaps natural for people to assume that [near-death] experiences came from elsewhere, from more supernatural sources.” But after seeing those neurochemical surges in her animals, she wondered about those last few seconds, hypothesizing that even experiences seeming to stretch for days in a person’s memory could originate from a brief “knee-jerk reaction” of the dying brain. © 2012 American Association for the Advancement of Science.

Keyword: Attention
Link ID: 18501 - Posted: 08.13.2013

Dina Fine Maron Nestled inside a generic-looking office building here in suburban Maryland, down the hall from cable-provider Comcast, sits the largest blood serum repository in the world. Seven freezers, each roughly the size of a high school basketball court, are stacked high with row upon row of small cardboard boxes containing tubes of yellow or pinkish blood serum, a liquid rich in antibodies and proteins, but devoid of cells. The freezers hover at –30 degrees Celsius—cold enough to make my pen dry up and to require that workers wear protective jumpsuits, hats, gloves and face masks. Four more empty freezers, which are now kept at room temperature, await future samples. The bank of massive freezers—and its contents—is maintained by the Department of Defense (DoD). The cache of government-owned serum may provide unique insights into the workings of various maladies when linked with detailed information on service members’ demographics, deployment locations and health survey data. New research projects tapping the precious serum could lead to breakthroughs in some of the hottest topics in military research—including the hunt for biomarkers for post-traumatic stress disorder and suicide risk. But DoD’s policy of keeping its samples in perpetuity—even after troops leave the force—could raise a few eyebrows. The military started collecting serum samples 28 years ago as a by-product of its HIV surveillance. Since then serum has been routinely collected from leftover blood from HIV tests or standard post-deployment health check-ups and then frozen for future reference. Now the Department of Defense Serum Repository (DoDSR) has swelled to include 55.5 million samples of serum from 10 million individuals—mostly service members, veterans or military applicants. The armed forces use DoDSR for general health surveillance to track infectious diseases and to shape health policies. But the repository is also ripe for targeted research programs. © 2013 Nature Publishing Group

Keyword: Stress; Genes & Behavior
Link ID: 18500 - Posted: 08.13.2013

By RONI CARYN RABIN Over the past two decades, the use of antidepressants has skyrocketed. One in 10 Americans now takes an antidepressant medication; among women in their 40s and 50s, the figure is one in four. Experts have offered numerous reasons. Depression is common, and economic struggles have added to our stress and anxiety. Television ads promote antidepressants, and insurance plans usually cover them, even while limiting talk therapy. But a recent study suggests another explanation: that the condition is being overdiagnosed on a remarkable scale. The study, published in April in the journal Psychotherapy and Psychosomatics, found that nearly two-thirds of a sample of more than 5,000 patients who had been given a diagnosis of depression within the previous 12 months did not meet the criteria for major depressive episode as described by the psychiatrists’ bible, the Diagnostic and Statistical Manual of Mental Disorders (or D.S.M.). The study is not the first to find that patients frequently get “false positive” diagnoses for depression. Several earlier review studies have reported that diagnostic accuracy is low in general practice offices, in large part because serious depression is so rare in that setting. Elderly patients were most likely to be misdiagnosed, the latest study found. Six out of seven patients age 65 and older who had been given a diagnosis of depression did not fit the criteria. More educated patients and those in poor health were less likely to receive an inaccurate diagnosis. Copyright 2013 The New York Times Company

Keyword: Depression
Link ID: 18499 - Posted: 08.13.2013

For most people, seeing a picture of a famous face — Oprah Winfrey, the Queen or Einstein, for instance — sparks immediate recognition and brings the name readily to the lips. But for people with a rare form of early-onset dementia called primary progressive aphasia, or PPA, the ability to identify a face or the person's name can be impaired. PPA strikes people aged about 40 to 65, much earlier than is typical for other forms of dementia like Alzheimer's disease. The condition is characterized by a deterioration in language and eventually the ability to communicate, although at least initially cognitive function in other areas remains intact, said Tamar Gefen, a PhD candidate in clinical neuropsychology at Northwestern University in Chicago. "Memory is fine, attention is fine and their planning, their judgment, their personality, their emotions — they're intact," explained Gefen, adding that early symptoms can include being unable to recall the names of familiar people or in some cases everyday objects. "Someone will come in and say: 'I can't remember my co-worker's name. I see her every day and I cannot remember it,"' she said. As the disease progresses, the person has difficulty speaking coherently and eventually stops talking altogether. Since the inability to put a name to a face can be an early sign of Alzheimer's disease, Gefen said it's important to properly diagnose the cause using specific tests that can identify PPA. © CBC 2013

Keyword: Alzheimers; Learning & Memory
Link ID: 18498 - Posted: 08.13.2013

By Bahar Gholipour Girls with anorexia may tend to have traits that are usually found in people with autism, a new study suggests. Researchers compared 66 teen girls who had anorexia with about 1,600 girls who did not have the eating disorder, using questionnaires they had previously developed to assess thinking and personality types in children with autism. Girls with the eating disorder anorexia may tend to have traits usually found in people with autism. The girls with anorexia were found to have more interest in systems and order, and lower scores in empathy — a profile more similar to people with autism than to typical adolescents, the researchers said. The finding suggests the two conditions may share certain features, such as rigid attitudes and behaviors, a tendency to be very self-focused and a fascination with detail, the researchers said. “Traditionally, anorexia has been viewed purely as an eating disorder. This is quite reasonable, since the girls’ dangerously low weight and their risk of malnutrition or even death has to be the highest priority” for treatment, said Simon Baron-Cohen, a professor of developmental psychopathology at the University of Cambridge in England. But his study suggests that “underlying the surface behavior, the mind of a person with anorexia may share a lot with the mind of a person with autism,” Baron-Cohen said. People with both conditions have a strong interest in organizational systems; girls with anorexia are intensely interested in the system that governs body weight, shape and food intake, he said. © 1996-2013 The Washington Post

Keyword: Anorexia & Bulimia; Autism
Link ID: 18497 - Posted: 08.13.2013

By Scicurious There are lots of challenges when it comes to studying the brain, but one of the biggest is that it’s very hard to see. Aside from being, you know, inside your skull, the many electrical and chemical signals which the brain uses are impossible to see with the naked eye. We have ways to look at neurons and how they convey information. For example, to record the electrical signals from a single neuron, you can piece it with a tiny electrode, to get access inside the membrane (electrophysiology). You can then stimulate the neuron to fire, or record as it fires spontaneously. For techniques like optogenetics, you can insert a gene into the neuron that makes it fire (or not) in response to light. When you shine the light, you can make the neuron fire. So you can make a neuron fire, or see a neuron fire. With things like voltammetry, we can see neurotransmitters, chemicals as they are released from a neuron and sent as signals on to other neurons. Techniques like these have made huge strides in what we understand about neurons and how they work. But…you can only do this for a few neurons at a time. This becomes a problem, because the brain does not work as one neuron at a time. Instead, neurons organize into networks, A neuron fires, which impinges upon many more neurons, all of which will react in different ways, depending on what input they receive and when. Often many neurons have to fire to get a result, often it’s a single specific pattern of neurons. An ideal technique would be one where we could see neurons fire spontaneously, in real time, and then see where those signals GO, to actually see a network in action. And where we could see it…without taking the brain out first. It looks like that technique might be here. © 2013 Scientific American

Keyword: Brain imaging
Link ID: 18496 - Posted: 08.13.2013

By C. CLAIBORNE RAY A. A widely discussed 2006 study of transit noise in New York City, measuring noise on buses as well as in subway cars and on platforms, was described at the time as the first such formal study published since the 1930s. Done by scientists at the Mailman School of Public Health at Columbia University and published in The Journal of Urban Health, the study concluded that noise levels at subway and bus stops could easily exceed recognized public health recommendations and had the potential to damage hearing, given sufficient exposure. For example, guidelines from the Environmental Protection Agency and the World Health Organization set a limit of 45 minutes’ exposure to 85 decibels, the mean noise level measured on subway platforms. And nearly 60 percent of the platform measurements exceeded that level. The maximum noise levels inside subway cars were even higher than those on the platforms, with one-fifth exceeding 100 decibels and more than two-thirds exceeding 90 decibels. The study recommended properly fitted earplugs and earmuff-type protectors in loud transit environments, saying they could cut noise levels significantly at the eardrum. And it warned that personal listening devices only increased the total noise and risk. © 2013 The New York Times Company

Keyword: Hearing
Link ID: 18495 - Posted: 08.13.2013

By Melinda Wenner Moyer Our world is determined by the limits of our five senses. We can't hear pitches that are too high or low, nor can we see ultraviolet or infrared light—even though these phenomena are not fundamentally different from the sounds and sights that our ears and eyes can detect. But what if it were possible to widen our sensory boundaries beyond the physical limitations of our anatomy? In a study published recently in Nature Communications, scientists used brain implants to teach rats to “see” infrared light, which they usually find invisible. The implications are tremendous: if the brain is so flexible it can learn to process novel sensory signals, people could one day feel touch through prosthetic limbs, see heat via infrared light or even develop a sixth sense for magnetic north. Miguel Nicolelis, a neurobiologist at Duke University, and his colleagues trained six rats to poke their nose inside a port when the LED light above it lit up. Then the researchers surgically attached infrared cameras to the rats' head and wired the cameras to electrodes they implanted into the rats' primary somatosensory cortex, a brain region responsible for sensory processing. When the camera detected infrared light, it stimulated the animals' whisker neurons. The stimulation became stronger the closer the rats got to the infrared light or the more they turned their head toward it, just as brain activation responds to light seen by the eyes. Then the scientists let the animals loose in their chambers, this time using infrared light instead of LEDs to signal the ports the rats should visit. At first, none of the rats used the infrared signals. But after about 26 days of practice, all six had learned how to use the once invisible light to find the right ports. © 2013 Scientific American

Keyword: Vision; Robotics
Link ID: 18494 - Posted: 08.13.2013

By GINA KOLATA Researchers studying two seemingly unrelated conditions — autism and cancer — have unexpectedly converged on a surprising discovery. Some people with autism have mutated cancer or tumor genes that apparently caused their brain disorder. Ten percent of children with mutations in a gene called PTEN, which causes cancers of the breast, colon, thyroid and other organs, have autism. So do about half of children with gene mutations that can lead to some kinds of brain and kidney cancer and large tumors in several organs, including the brain. That is many times the rate of autism in the general population. “It’s eerie,” Evan Eichler, a professor of genome science at the University of Washington, said about the convergence. He and others caution that the findings apply to only a small proportion of people with autism; in most cases, the cause remains a mystery. And as with nearly all genetic disorders, not everyone with the mutations develops autism or cancer, or other disorders associated with the genes, like epilepsy, enlarged brains and benign brain tumors. But researchers say the findings are intriguing, given that there are no animals that naturally get autism, no way of analyzing what might cause autism in developing brains and no cure. The newly discovered link has enabled scientists to genetically engineer mice with many symptoms of the human disorder. And it has led to the first clinical trial of a treatment for children with autism, using the drug that treats tumors that share the same genetic basis. Richard Ewing of Nashville, a 10-year-old who has a form of autism caused by a tumor-causing gene, is among those in the new study. His parents, Alexandra and Rick Ewing, know he is at risk for tumors in the brain, heart, kidney, skin and eyes. But that bad news was tempered by his eligibility for the clinical trial, which has only just started. © 2013 The New York Times Company

Keyword: Autism; Genes & Behavior
Link ID: 18493 - Posted: 08.12.2013

By Neuroskeptic Thanks to newly-developed “super-resolution” microscopy techniques, a group of French neuroscientists have discovered a remarkable world of complexity on a tiny scale. Writing in the Journal of Neuroscience, Deepak Nair colleagues report that: Super-Resolution Imaging Reveals That AMPA Receptors Inside Synapses Are Dynamically Organized in Nanodomains Regulated by PSD95 Neurons communicate with each other via chemical synapses. Here, two cells almost touch each other, and one of them can release a messenger molecule (neurotransmitter) which activates proteins (receptors) on the receiving (postsynaptic) neuron, thus conveying information. Here’s part of a single cell: the synapses are where the little ‘spines’ or ‘bulbs’ meet those present on another cell (not pictured).Until now, it’s been believed that within a synapse, receptors are just randomly distributed over the postsynaptic cell membrane. However, Nair et al’s work reveals an unsuspected level of organization. It turns out that receptors – or at least AMPA receptors, the only kind they looked at – are in fact clustered together into structures the authors dub nanodomains. Each nanodomain contains about 20 receptors, and is about 70 nanometers across. This is small. It’s roughly the size of a virus, and about 1/1000th the width of a human hair. When I saw this picture, it didn’t call to mind anything else I’d ever seen in neuroscience. Rather, it reminded me of the Hubble Deep Field images of distant galaxies… and funnily enough, one of the proteins that plays a secondary role in this paper is called stargazin.

Keyword: Brain imaging
Link ID: 18492 - Posted: 08.12.2013