Most Recent Links
Follow us on Facebook and Twitter, or subscribe to our mailing list, to receive news updates. Learn more.
By Sandra G. Boodman, Dorsey Davidge felt her thrumming anxiety burst into barely controlled panic as she watched her 14-year-old daughter Cate Chapin struggle to get from her bedroom to the bathroom. During the last week of January, the eighth-grader contracted what appeared to be a bad case of the flu. After a week, a doctor decided she had pneumonia, a diagnosis that was later changed to a possible infectious disease. Davidge, a single mother who lives in McLean, had maintained her equanimity during the early days of Cate’s illness. But when she saw that her older daughter was unable to walk 10 feet without stopping midway to rest, she was shocked by how cadaverous-looking Cate had become in a matter of weeks. “I was really scared for the first time,” Davidge said. “She was incredibly weak, and I thought, “ ‘Oh, my God, my child is just wasting away.’ ” By then, the 5-foot-2 Cate, a skinny 95 pounds before she got sick, had shriveled to a little over 80 pounds. She had no appetite, was barely drinking anything and seemed unable to consume more than a quarter of a bagel at a sitting. “That day was the last straw,” Davidge recalled. She telephoned Cate’s pediatrician, who agreed that the girl needed to be admitted immediately to a Northern Virginia hospital. It would take another harrowing month — which included the insertion of a feeding tube to help restore Cate’s weight, consultations with a bevy of specialists and numerous tests — before doctors figured out what was actually wrong, a diagnosis made possible after Cate developed a seemingly unrelated condition that sent her to an ophthalmologist. © 1996-2013 The Washington Post
Keyword: Anorexia & Bulimia
Link ID: 18943 - Posted: 11.19.2013
By EMILY ANTHES Humans have no exclusive claim on intelligence. Across the animal kingdom, all sorts of creatures have performed impressive intellectual feats. A bonobo named Kanzi uses an array of symbols to communicate with humans. Chaser the border collie knows the English words for more than 1,000 objects. Crows make sophisticated tools, elephants recognize themselves in the mirror, and dolphins have a rudimentary number sense. Anolis evermanni lizards normally attack their prey from above. The lizards were challenged to find a way to access insects that were kept inside a small hole covered with a tightfitting blue cap. And reptiles? Well, at least they have their looks. In the plethora of research over the past few decades on the cognitive capabilities of various species, lizards, turtles and snakes have been left in the back of the class. Few scientists bothered to peer into the reptile mind, and those who did were largely unimpressed. “Reptiles don’t really have great press,” said Gordon M. Burghardt, a comparative psychologist at the University of Tennessee at Knoxville. “Certainly in the past, people didn’t really think too much of their intelligence. They were thought of as instinct machines.” But now that is beginning to change, thanks to a growing interest in “coldblooded cognition” and recent studies revealing that reptile brains are not as primitive as we imagined. The research could not only redeem reptiles but also shed new light on cognitive evolution. Because reptiles, birds and mammals diverged so long ago, with a common ancestor that lived 280 million years ago, the emerging data suggest that certain sophisticated mental skills may be more ancient than had been assumed — or so adaptive that they evolved multiple times. © 2013 The New York Times Company
Female mice that compete in promiscuous environments have sexier smelling sons, research has found. Scientists in Utah, US, studied the pheromones produced in the urine of male mice. They found that those whose mothers competed for mates were more sexually attractive to females. But this success was short-lived: their life spans were shorter than mice with monogamous parents. Adam Nelson from the University of Utah completed the study alongside senior author Prof Wayne Potts. It is published in the journal Proceedings of the National Academy of Sciences. "Only recently have we started to understand that environmental conditions experienced by parents can influence the characteristics of their offspring. This study is one of the first to show this kind of 'epigenetic' process working in a way that increases the mating success of sons," said Prof Potts. Epigenetics is the study of how differences in a parent's environment can influence how its offspring's genes are expressed. The researchers studied domestic mice which are usually paired in a cage and therefore breed with only one partner. To reintroduce the social competition wild mice experience, lab mice were kept in "mouse barns" which were large enclosures divided by mesh to create territories. The mice were able to climb over the mesh to access nest boxes, feeding stations and drinking water. BBC © 2013
By JOHN TIERNEY How aggressive is the human female? When the anthropologist Sarah B. Hrdy surveyed the research literature three decades ago, she concluded that “the competitive component in the nature of women remains anecdotal, intuitively sensed, but not confirmed by science.” Science has come a long way since then, as Dr. Hrdy notes in her introduction to a recent issue of Philosophical Transactions of the Royal Society devoted entirely to the topic of female aggression. She credits the “stunning” amount of new evidence partly to better research techniques and partly to the entry of so many women into scientific fields once dominated by men. The existence of female competition may seem obvious to anyone who has been in a high-school cafeteria or a singles bar, but analyzing it has been difficult because it tends be more subtle and indirect (and a lot less violent) than the male variety. Now that researchers have been looking more closely, they say that this “intrasexual competition” is the most important factor explaining the pressures that young women feel to meet standards of sexual conduct and physical appearance. The old doubts about female competitiveness derived partly from an evolutionary analysis of the reproductive odds in ancient polygynous societies in which some men were left single because dominant males had multiple wives. So men had to compete to have a chance of reproducing, whereas virtually all women were assured of it. But even in those societies, women were not passive trophies for victorious males. They had their own incentives to compete with one another for more desirable partners and more resources for their children. And now that most people live in monogamous societies, most women face the same odds as men. In fact, they face tougher odds in some places, like the many college campuses with more women than men. © 2013 The New York Times Company
by Erika Engelhaupt When I was in graduate school, I once gassed out my lab with the smell of death. I was studying the products of plant decomposition, and I had placed copious quantities of duckweed into large tubs and let the mix decompose for a few weeks. Duckweed is a small floating aquatic plant; it looks harmless enough. But when I dragged my tubs into the lab and set up a pump and filtration system, all hell broke loose. The filter clogged, the back pressure threw the hose off the pump, and a spray of decomposed mess flew all over a poor professor who had come in to help. For the rest of the day, he smelled like a pile of dead raccoons. That day, I learned about cadaverine and putrescine. These two molecules are produced during the decomposition of proteins, when the amino acids lysine and ornithine break down, and they are largely responsible for the smell of rotting flesh. My mistake in the lab was to think that rotting plants are more innocuous than rotting animals. Duckweed, it turns out, has such high protein levels that it’s used as animal feed, and those proteins, like any proteins, can create a deathly stench. The smells of cadaverine and putrescine tend to provoke a strong reaction (as I learned once the duckweed stench subsided and my labmates were able to return to the lab). But not every animal finds the odors disgusting. Carrion flies, rats and other animals that eat or lay eggs in dead things are attracted to the molecules. So researchers have started to look for exactly how animals tune in to these smells. Pinning down animals' odor detectors gives researchers a way to study aversion or attraction to certain objects. And understanding how these behavioral responses work will, I believe, help researchers clarify why humans feel the distinct emotion known as disgust. © Society for Science & the Public 2000 - 2013.
By Tanya Lewis and LiveScience SAN DIEGO — Being a social butterfly just might change your brain: In people with a large network of friends and excellent social skills, certain brain regions are bigger and better connected than in people with fewer friends, a new study finds. The research, presented here Tuesday (Nov. 12) at the annual meeting of the Society for Neuroscience, suggests a connection between social interactions and brain structure. "We're interested in how your brain is able to allow you to navigate in complex social environments," study researcher MaryAnn Noonan, a neuroscientist at Oxford University, in England, said at a news conference. Basically, "how many friends can your brain handle?" Noonan said. Scientists still don't understand how the brain manages human behavior in increasingly complex social situations, or what parts of the brain are linked to deviant social behavior associated with conditions like autism and schizophrenia. Studies in macaque monkeys have shown that brain areas involved in face processing and in predicting the intentions of others are larger in animals living in large social groups than in ones living in smaller groups. To investigate these brain differences in humans, Noonan and her colleagues at McGill University, in Canada, recruited 18 participants for a structural brain-imaging study. They asked people how many social interactions they had experienced in the past month, in order to determine the size of their social networks. As was the case in monkeys, some brain areas were enlarged and better connected in people with larger social networks. In humans, these areas were the temporal parietal junction, the anterior cingulate cortex and the rostral prefrontal cortex, which are part of a network involved in "mentalization" — the ability to attribute mental states, thoughts and beliefs to another. © 2013 Scientific American
by Bob Holmes When it comes to evolution, there is no such thing as perfection. Even in the simple, unchanging environment of a laboratory flask, bacteria never stop making small tweaks to improve their fitness. That's the conclusion of the longest-running evolutionary experiment carried out in a lab. In 1988, Richard Lenski of Michigan State University in East Lansing began growing 12 cultures of the same strain of Escherichia coli bacteria. The bacteria have been growing ever since, in isolation, on a simple nutrient medium – a total of more than 50,000 E. coli generations to date. Every 500 generations, Lenski freezes a sample of each culture, creating an artificial "fossil record". This allows him to resurrect the past and measure evolutionary progress by comparing how well bacteria compete against each other at different points in the evolutionary process. No upper limit After 10,000 generations, Lenski thought that the bacteria might approach an upper limit in fitness beyond which no further improvement was possible. But the full 50,000 generations of data show that isn't the case. When pitted against each other in an equal race, new generations always grew faster than older ones. In other words, fitness never stopped increasing. Their results fit a mathematical pattern known as a power law, in which something can increase forever, but at a steadily diminishing rate. "Even if we extrapolate it to 2.5 billion generations, there's no obvious reason to think there's an upper limit," says Lenski. © Copyright Reed Business Information Ltd.
Link ID: 18937 - Posted: 11.16.2013
Helen Shen To researchers who study how living things move, the octopus is an eight-legged marvel, managing its array of undulating appendages by means of a relatively simple nervous system. Some studies have suggested that each of the octopus’s tentacles has a 'mind' of its own, without rigid central coordination by the animal’s brain1. Now neuroscientist Guy Levy and his colleagues at the Hebrew University in Jerusalem report that the animals can rotate their bodies independently of their direction of movement, reorienting them while continuing to crawl in a straight line. And, unlike species that use their limbs to move forward or sideways relative to their body's orientation, octopuses tend to slither around in all directions. The team presented its findings on 10 November at the annual meeting of the Society for Neuroscience in San Diego, California. The new description of octopus movement is “not how one would imagine that would happen, but it seems to give a lot of control to the animal", says Gal Haspel, a neuroscientist at the New Jersey Institute of Technology in Newark. Haspel studies worm locomotion, and he was also surprised by the researchers’ report that the octopus pushes itself with worm-like contractions of its tentacles. Different combinations flex together to produce movement in different directions. Levy, who began the research as part of a project to design and control flexible, octopus-like robots, says that the work could also help to uncover basic biological principles of locomotion. Levy’s team deconstructed octopus movement using a transparent tank rigged with a system of mirrors and video cameras, in which they tested nine adult common octopuses (Octopus vulgaris). © 2013 Nature Publishing Group
When President Obama announced his plan to explore the mysteries of the human brain seven months ago, it was long on ambition and short on details. Now some of the details are being sketched in. They will include efforts to restore lost memories in war veterans, create tools that let scientists study individual brain circuits and map the nervous system of the fruit fly. The Defense Advanced Projects Agency, or DARPA, which has committed more than $50 million to the effort, offered the clearest plan. The agency wants to focus on treatments for the sort of brain disorders affecting soldiers who served in Iraq and Afghanistan, according to , deputy director of . "That is our constituency," Ling said at a news conference at the Society for Neuroscience meeting in San Diego. A colored 3-D MRI scan of the brain's white matter pathways traces connections between cells in the cerebrum and the brainstem. So DARPA will be working on problems including PTSD and traumatic brain injuries, Ling says. In particular, the agency wants to help the soldier who has "a terribly damaged brain and has lost a significant amount of declarative memory," Ling said. "We would like to restore that memory." DARPA hopes to do that with an implanted device that will take over some functions of the brain's hippocampus, an area that's important to memory. The agency has already used a device that does this in rodents, Ling said, and the goal is to move on to people quickly. The agency plans to use the same approach that created a better in record time, Ling said. "We went from idea to prototype in 18 months," he says. This undated X-ray image from the Cleveland Clinic shows electrodes implanted in a patient's brain. The method, known as deep brain stimulation, has traditionally been used to treat diseases such as Parkinson's, but new research indicates it could be helpful for patients with obsessive-compulsive disorder. ©2013 NPR
by Jessica Griggs, San Diego Pregnant women may pass on the effects of stress to their fetus by way of bacterial changes in their vagina, suggests a study in mice. It may affect how well their baby's brain is equipped to deal with stress in adulthood. The bacteria in our body outnumber our own cells by about 10 to 1, with most of them found in our gut. Over the last few years, it has become clear that the bacterial ecosystem in our body – our microbiome – is essential for developing and maintaining a healthy immune system. Our gut bugs also help to prevent germs from invading our bodies, and help to absorb nutrients from food. A baby gets its first major dose of bacteria in life as it passes through its mother's birth canal. En route, the baby ingests the mother's vaginal microbes, which begin to colonise the newborn's gut. Chris Howerton, then at the University of Pennsylvania in Philadelphia, and his colleagues wanted to know if this initial population of bacteria is important in shaping a baby's neurological development, and whether that population is influenced by stress during pregnancy. The first step was to figure out what features of the mother's vaginal microbiome might be altered by stress, and then see if any of those changes were transmitted to the offspring's gut. © Copyright Reed Business Information Ltd
by Laura Sanders SAN DIEGO — Teenagers’ brains are wired to confront a threat instead of retreating, research presented November 10 at the annual Society for Neuroscience meeting suggests. The results may help explain why criminal activity peaks during adolescence. Kristina Caudle of Weill Cornell Medical College in New York City and colleagues tested the impulse control of 83 people between ages 6 and 29. In the experiment, participants were asked to press a button when a photo of a happy face quickly flashed before them. They were told not to press the button when a face had a threatening expression. When confronted with the threatening faces, people between the ages of 13 and 17 were more likely to impulsively push the button than children and adults were, the team found. Brain scans revealed that activity in an area called the orbital frontal cortex peaked in teens when they successfully avoided pushing the button, suggesting that this region curbs the impulse to react, Caudle said. It’s not clear why children don’t have the same impulsive reaction to threatening faces. More studies could determine how the relevant brain systems grow and change, Caudle said. © Society for Science & the Public 2000 - 2013.
by Jessica Griggs, San Diego Glugging lots of sugary drinks won't just make you fat, it might also lead to changes in the brain that have been linked to cancer and Alzheimer's – at least in rats. This finding comes from the first analysis of how sugary drinks affect proteins in the brain. It showed that 20 per cent of the proteins produced in a brain region related to decision-making were altered in rats that drank sugary drinks compared with those given water. It is well established that drinking sugar-sweetened drinks is linked to obesity and diabetes, as well as increasing the risk of cardiovascular problems. A recent estimate put the number of deaths associated with soft drinks at 184,000 a year globally. But the effects of sugar-rich drinks on the brain have received much less attention. "For many people around the world, soft drinks are their sole source of liquid, or at least they provide a very high proportion of their daily calories", says Jane Franklin at the behavioural neuropharmacology lab at Macquarie University in Sydney, Australia, who carried out the study. "We know that soft drinks are bad for the body, so it's reasonable to assume that they aren't doing anything good for your brain either". To find out, Franklin and her colleague Jennifer Cornish gave 24 adult rats either water or a solution of water containing 10 per cent sugar – about the proportion you would find in an average can of soft drink – for 26 days. © Copyright Reed Business Information Ltd.
Link ID: 18932 - Posted: 11.16.2013
By BARRY MEIER Addiction experts protested loudly when the Food and Drug Administration approved a powerful new opioid painkiller last month, saying that it would set off a wave of abuse much as OxyContin did when it first appeared. An F.D.A. panel had earlier voted, 11 to 2, against approval of the drug, Zohydro, in part because unlike current versions of OxyContin, it is not made in a formulation designed to deter abuse. Now a new issue is being raised about Zohydro. The drug will be manufactured by the same company, Alkermes, that makes a popular medication called Vivitrol, used to treat patients addicted to painkillers or alcohol. In addition, the company provides financial support to a leading professional group that represents substance abuse experts, the American Society of Addiction Medicine. For some critics, the company’s multiple roles in the world of painkillers is troubling. Dr. Gregory L. Jones, an addiction specialist in Louisville, Ky., said he had long been concerned about financial links between the group and the drug industry, adding that the Zohydro situation amplified those potential conflicts. Dr. Stuart Gitlow, the current president of the American Society of Addiction Medicine, said he had been unaware until now of Alkermes’s involvement with Zohydro. Dr. Gitlow, who is affiliated with Mount Sinai Hospital in New York City, said that the group would seek more information from Alkermes about the situation and then decide what, if anything, to do next. Officials of Alkermes appear to recognize the issue they face. In recent years, the company has been trying to increase sales of Vivitrol, a form of a drug called naltrexone, that is used to treat both alcoholism and opioid addiction. © 2013 The New York Times Company
Daniel Freeman and Jason Freeman Which illness frightens you most? Cancer? Stroke? Dementia? To judge from tabloid coverage, the condition we should really fear isn't physical at all. "Scared of mum's schizophrenic attacks", "Knife-wielding schizophrenic woman in court", "Schizo stranger killed dad", "Rachel murder: schizo accused", and "My schizophrenic son says he'll kill… but he's escaped from secure hospitals 7 times" are just a few of dozens of similar headlines we found in a cursory internet search. Mental illness, these stories imply, is dangerous. And schizophrenia is the most dangerous of all. Such reporting is unhelpful, misleading and manipulative. But it may be even more inaccurate than it first appears. This is because scientists are increasingly doubtful whether schizophrenia – a term invented more than a century ago by the psychiatric pioneer Eugen Bleuler – is a distinct illness at all. This isn't to say that individuals diagnosed with the condition don't have genuine and serious mental health problems. But how well the label "schizophrenia" fits those problems is now a very real question. What's wrong with the concept of schizophrenia? For one thing, research indicates the term may simply be functioning as a catch-all for a variety of separate problems. Six main conditions are typically caught under the umbrella of schizophrenia: paranoia; grandiosity (delusional beliefs that one has special powers or is famous); hallucinations (hearing voices, for example); thought disorder (being unable to think straight); anhedonia or the inability to experience pleasure; and diminished emotional expression (essentially an emotional "numbness"). But how many of these problems a person experiences, and how severely, varies enormously. Having one doesn't mean you'll necessarily develop any of the others. © 2013 Guardian News and Media Limited
Link ID: 18930 - Posted: 11.16.2013
SAN DIEGO, CALIFORNIA—Compulsive gamblers aren’t necessarily greedier than the rest of us—their brains may just be wired to favor money over sex. That’s the conclusion of a study presented here today at the Society for Neuroscience conference. This tendency to prioritize money over more basic desires resembles other addictions like alcoholism, researchers say, and could point toward new therapies. Of the millions of people who gamble for fun or profit, about 1% to 2% qualify as pathological gamblers. They can't quit despite encountering serious negative consequences—going into debt, damaging relationships, and even smashing up slot machines and getting arrested when the habit gets out of control. This inability to stop even after sustained loss is one reason gambling recently became the first behavioral addiction to be recognized by psychiatry's most frequently used diagnostic manual, the DSM-5, says Guillaume Sescousse, a neuroscientist at the Radboud University Nijmegen in the Netherlands who led the new study. After all, he says, professional poker players can play for 10 hours a day and not be considered addicts—so long as they can stop when their luck runs out. Researchers have long hypothesized that the basis for gambling addiction might be hypersensitivity to the highs of winning money, caused by dysfunctional wiring in neural circuits that process reward. Studies have produced conflicting results, however, so Sescousse decided to investigate an alternative hypothesis. He wondered if instead of being overly sensitive to monetary reward, compulsive gamblers were less sensitive to other rewarding things, like alcohol and sex. © 2013 American Association for the Advancement of Science
by Jessica Griggs, San Diego No practice required. Wouldn't it be great if you could get better at playing sport or hone your piano skills simply by thinking about it? A small pilot study suggests that it might be possible. In the last few years, brain training using computer games that provide neurofeedback – a real-time representation of your brain activity – has become a popular, if controversial, method of enhancing cognitive abilities such as spatial memory, planning and multitasking. It has even been used to help actors get into character. Most of the games aim to enhance activation in a single part of the brain. But motor skills are known to involve two main areas – the premotor cortex and the supplementary motor cortex. Both are involved when people make movements or imagine moving. Brain activity between these regions is known to be less synchronised in people who are poor at motor tasks than in those who excel at them. So to see if brain training could target both areas and improve motor performance, Sook-Lei Liew and her colleagues from the National Institute of Neurological Disorders and Stroke in Bethesda, Maryland, recruited eight young adults. The researchers and asked the participants to watch a white circle on a screen while an fMRI machine scanned their brain. When the circle turned into a red triangle, the volunteers were told to move their fingers. This movement caused activation in their premotor cortex and supplementary motor cortex, which in turn moved a bar on the screen. The higher the synchronisation of activity between the two brain areas, the higher the bar went. © Copyright Reed Business Information Ltd.
Link ID: 18928 - Posted: 11.14.2013
by Laura Sanders SAN DIEGO — When stress during pregnancy disrupts a growing baby’s brain, blame bacteria. Microbes take part in an elaborate chain reaction, a new study finds: First, stress changes the populations of bacteria dwelling in a pregnant mouse’s vagina; those changes then affect which bacteria colonize a newborn pup’s gut; and the altered gut bacteria change the newborn’s brain. The research, presented at the annual Society for Neuroscience meeting, may help explain how a stressful environment early in life can make a person more susceptible to disorders such as autism or schizophrenia. The finding also highlights the important and still mysterious ways that the bacteria living in bodies can influence the brain. “This is really fascinating and promising work,” said neuroscientist Cory Burghy of the University of Wisconsin–Madison. “I am excited to take a look at how these systems interact in humans,” she said. Stress during pregnancy dramatically shifts the mix of bacteria that dwell in the vagina, Christopher Howerton of the University of Pennsylvania reported November 11. The alarming odor of foxes, loud noise, physical restraints and other stressful situations during a mouse’s pregnancy changed the composition of its vaginal bacteria, he and his colleagues found. The population of helpful Lactobacillus bacteria, for instance, decreased after stress. And because newborn mouse pups populate their guts with bacteria dwelling in their mother’s birth canal, microbes from mom colonize the baby’s gut. Mice born to moms with lower levels of Lactobacillus in the vagina had lower levels of Lactobacillus in their guts soon after they were born, the team reported. © Society for Science & the Public 2000 - 2013
Ed Yong Humanity's success depends on the ability of humans to copy, and build on, the works of their predecessors. Over time, human society has accumulated technologies, skills and knowledge beyond the scope of any single individual. Now, two teams of scientists have independently shown that the strength of this cumulative culture depends on the size and interconnectedness of social groups. Through laboratory experiments, they showed that complex cultural traditions — from making fishing nets to tying knots — last longer and improve faster at the hands of larger, more sociable groups. This helps to explain why some groups, such as Tasmanian aboriginals, lost many valuable skills and technologies as their populations shrank. “For producing fancy tools and complexity, it’s better to be social than smart,” says psychologist Joe Henrich of the University of British Columbia in Vancouver, Canada, the lead author of one of the two studies, published today in Proceedings of the Royal Society B1. “And things that make us social are going to make us seem smarter.” “There were some theoretical models to explain these phenomena but no one had done experiments,” says evolutionary biologist Maxime Derex of the University of Montpellier, France, who led the other study, published online today in Nature2. Derex’s team asked 366 male students to play a virtual game in which they gained points — and eventually money — by building either an arrowhead or a fishing net. The nets offered greater rewards, but were also harder to make. The students watched video demonstrations of the two tasks in groups of 2, 4, 8 or 16, before attempting the tasks individually. Their arrows and nets were tested in simulations and scored. After each trial, they could see how other group members fared, and watch a step-by-step procedure for any one of the designs. © 2013 Nature Publishing Group
By Melissa Hogenboom Science reporter, BBC News Changes to specific cells in the retina could help diagnose and track the progression of Alzheimer's disease, scientists say. A team found genetically engineered mice with Alzheimer's lost thickness in this layer of eye cells. As the retina is a direct extension of the brain, they say the loss of retinal neurons could be related to the loss of brain cells in Alzheimer's. The findings were revealed at the US Society for Neuroscience conference. The team believes this work could one day lead to opticians being able to detect Alzheimer's in a regular eye check, if they had the right tools. Alterations in the same retinal cells could also help detect glaucoma - which causes blindness - and is now also viewed as a neurodegenerative disease similar to Alzheimer's, the researchers report. Scott Turner, director of the memory disorders programme at Georgetown University Medical Center, said: "The retina is an extension of the brain so it makes sense to see if the same pathologic processes found in an Alzheimer's brain are also found in the eye." Dr Turner and colleagues looked at the thickness of the retina in an area that had not previously been investigated. This included the inner nuclear layer and the retinal ganglion cell layer. They found that a loss of thickness occurred only in mice with Alzheimer's. The retinal ganglion cell layer had almost halved in size and the inner nuclear layer had decreased by more than a third. BBC © 2013
by Colin Barras IT'S musical mind-reading. Your patterns of brain activity can show what song you are listening to. In the area of the brain that processes sound – the auditory cortex – different neurons become active in response to different sound frequencies. So it should be possible to work out which musical note someone is listening to just by looking at this activity, says Geoff Boynton at the University of Washington in Seattle. To find out, Boynton and his colleague Jessica Thomas had four volunteers listen to various notes, while they used fMRI to record the resulting neural activity. "Then the game is to play a song and use the neural activity to guess what was played," he says. They were able to identify melodies like Twinkle, Twinkle, Little Star from neural activity alone, Boynton told the Society for Neuroscience annual meeting in San Diego, California, this week. The results could help probe the neural roots of people who are tone deaf. This can be a problem for people with cochlear implants, says Rebecca Schaefer, who researches neuroscience and music at the University of California in Santa Barbara. Another study into the music of the mind, also presented this week in San Diego, suggests that the brain is highly attuned to rhythm and this might explain why we talk at certain speeds. David Poeppel at New York University and his colleagues monitored brain activity in 12 volunteers while they listened to three piano sonatas. One sonata had a quick tempo, with around eight notes per second, one had five per second, and the slowest had one note every 2 seconds. © Copyright Reed Business Information Ltd.