By Bruce Bower An ancient finger bone recently landed a genetic sucker punch on scientists studying human evolution. DNA extracted from this tiny fossil, unearthed in Siberia’s Denisova Cave, unveiled a humanlike population that interbred with people in East Asia at least 44,000 years ago. Denisovans supplied nearly 5 percent of the genes of native groups now living in Australia, New Guinea and on several nearby islands. That molecular shocker followed a revelation that the genetic instruction books of people from Australia to the Americas contain a roughly 2.5 percent contribution from Neandertals, modern humans’ evolutionary cousins that died out around 30,000 years ago. Pulling the DNA shades up on ancient human dalliances with Neandertals and closely related Denisovans has sparked a scientific consensus that members of mobile human groups interbred with closely related populations in the Homo genus during the Stone Age. “The question is no longer ‘When did ancient populations such as Neandertals go extinct?’ but ‘What happened to those populations and to modern humans as a result of interbreeding?’ ” says anthropologist John Hawks of the University of Wisconsin–Madison. Clear signs of interbreeding have left archaeologists and other students of the Stone Age scrambling to revisit existing ideas about Homo sapiens’ evolutionary past. A dominant theory holding that humans evolved in Africa and left on neat one-way routes to Asia and Europe has to be revised. Instead, these ancient people must have followed a tangled web of paths taking them to other continents and sometimes reversing course. During these travels, humans encountered Neandertals, Denisovans and probably other humanlike populations that were already traipsing interconnected avenues through Asia and Europe. © Society for Science & the Public 2000 - 2012

Keyword: Evolution
Link ID: 17161 - Posted: 08.14.2012

by Carol Cruzan Morton Migraines are a battle of the sexes that women might prefer not winning. Each year, roughly three times more women than men—up to 18% of all women—suffer from the debilitating headaches, as tallied by epidemiological surveys in Europe and the United States. A new brain imaging study may explain the divide: The brains of women with migraines appear to be built differently than those of their male counterparts. To conduct the study, researchers headed by David Borsook, a neurologist and neurobiologist of Boston Children’s Hospital and Harvard Medical School, recruited 44 men and women, half of whom were migraine sufferers. The women who had migraines rated them as being as intense as the men did, but they tended to find them more unpleasant. Borsook says the distinction is analogous to the loudness of fingernails scratching on a chalkboard versus the torment of hearing the sound. The team then scanned the brains of the volunteers. The researchers gathered two kinds of data sets, one that captured brain shapes and features, and one that measured brain activity. Female migraine sufferers showed slightly thicker gray matter in two regions: one, the posterior insula, is well-known in pain processing; the other, the precuneus, has been recently linked to migraines but is more widely known as a fundamental brain hub that may house a person's consciousness or sense of self. The other volunteers, including the male migraine sufferers, did not show this thickening. All of the scans were done when people did not have a migraine. To figure out what those structural changes meant, lead author Nasim Maleki, a medical physicist at Boston Children's Hospital and Harvard Medical School, returned to the MRI scans of only those men and women with episodic migraines. © 2010 American Association for the Advancement of Science.

Keyword: Pain & Touch; Hormones & Behavior
Link ID: 17160 - Posted: 08.14.2012

By NATALIE ANGIER Deseada Parejo, a biologist at the Arid Zones Experimental Research Station in Almería, Spain, was studying family dynamics behavior in Eurasian rollers — spectacular jay-size birds with long, slender tails and the Cray-Pas colors of parakeets. On removing one of the nestlings for a standard check of size and weight, she practically jumped at its horror-film response: The tiny chick gaped its mouth wide and vomited up a big dose of sticky orange liquid, enough to fill half a teaspoon. Dr. Parejo touched a second chick, a third, a sixth, and got the same expulsory retort. “I have worked with many other bird species,” she said, “but I never found anything similar to this vomiting behavior before.” Not only that: The fluid had a distinctive, evolving odor. “It’s like orange juice at first,” she said. “Then it begins to smell like insects, like the prey the parents provide.” In the current issue of Biology Letters, Dr. Parejo and her colleagues describe their study of this noteworthy aroma, which they designate the roller nestlings’ “smell of fear.” The researchers said that while the reflux reflex might well serve as a defense mechanism — helping to repel nest predators like snakes and rodents — they were interested in a different question: whether the parents could detect the olfactory cry of alarm, and if so, how they reacted. The answer to the first question was yes. But the parental response to the eau of offspring terror was anything but heroic; instead, it was a bit like those childhood nightmares, where the louder you cry out to Mom and Dad in a crowd, the faster they leave you behind. © 2012 The New York Times Company

Keyword: Emotions; Chemical Senses (Smell & Taste)
Link ID: 17159 - Posted: 08.14.2012

By Tina Hesman Saey When a cold takes away a person’s sense of smell, part of the brain that helps link odors with memory, emotion and reward works overtime in preparation for the return of air flow. The way smell rebounds from a period of diminished sensory input distinguishes it from the other senses, researchers at the Northwestern University School of Medicine in Chicago report online August 12 in Nature Neuroscience. Other senses tend to back off when their functions are restricted. When a person wears a patch over one eye, for example, the part of the brain devoted to processing information from that eye weakens while the part linked to the other eye grows stronger. The same is true for hearing and touch, such as when a person goes deaf in one ear or loses a finger. To find out what happens to the olfactory system — the part of the brain that processes scents — when it’s completely odor deprived, Northwestern neuroscientist Joanna Keng Nei Wu and her colleagues set up a scent-free zone in a hospital’s research wing. Volunteers had to give up scented toiletries and spend a week with cotton stuffed up their nostrils to seal their noses off from the outside world. The researchers even took away the volunteers’ toothpaste, forcing them to brush with baking soda instead. Despite the hardships, it wasn’t difficult to find willing volunteers, Wu says. “We had a lot of medical students who wanted us to lock them up in the hospital for a week so they could study.” © Society for Science & the Public 2000 - 2012

Keyword: Chemical Senses (Smell & Taste)
Link ID: 17158 - Posted: 08.14.2012

By RUTH PADAWER The night before Susan and Rob allowed their son to go to preschool in a dress, they sent an e-mail to parents of his classmates. Alex, they wrote, “has been gender-fluid for as long as we can remember, and at the moment he is equally passionate about and identified with soccer players and princesses, superheroes and ballerinas (not to mention lava and unicorns, dinosaurs and glitter rainbows).” They explained that Alex had recently become inconsolable about his parents’ ban on wearing dresses beyond dress-up time. After consulting their pediatrician, a psychologist and parents of other gender-nonconforming children, they concluded that “the important thing was to teach him not to be ashamed of who he feels he is.” Thus, the purple-pink-and-yellow-striped dress he would be wearing that next morning. For good measure, their e-mail included a link to information on gender-variant children. When Alex was 4, he pronounced himself “a boy and a girl,” but in the two years since, he has been fairly clear that he is simply a boy who sometimes likes to dress and play in conventionally feminine ways. Some days at home he wears dresses, paints his fingernails and plays with dolls; other days, he roughhouses, rams his toys together or pretends to be Spider-Man. Even his movements ricochet between parodies of gender: on days he puts on a dress, he is graceful, almost dancerlike, and his sentences rise in pitch at the end. On days he opts for only “boy” wear, he heads off with a little swagger. Of course, had Alex been a girl who sometimes dressed or played in boyish ways, no e-mail to parents would have been necessary; no one would raise an eyebrow at a girl who likes throwing a football or wearing a Spider-Man T-shirt. © 2012 The New York Times Company

Keyword: Sexual Behavior; Development of the Brain
Link ID: 17157 - Posted: 08.13.2012

By Karen Weintraub Paul Barney had his first seizure four days after his fourth birthday. By the time he was 10, his mom worried that if they didn’t get the seizures under control soon, he might lose IQ points along with his ready smile. When Brian Manning, 11, had a seizure on the school playground – instead of in his bed as usual – his parents knew it was time for drastic action. He’d already had brain surgery once, but doctors said he might need five or six more operations. Or he could have one, to completely remove the right half of his brain. Both boys have epilepsy and recently underwent surgery at Boston Children’s Hospital. And both represent the promise and frustration of epilepsy treatment today. Patients have more options, and there is more awareness, less stigma, and a better understanding of epilepsy than there has ever been. But available medications can’t control seizures in about one-third of patients, including Paul and Brian, and while surgery is safer, it still comes with high risks. It also remains unclear what causes the electrical disturbance in patients’ brains that triggers seizures. Roughly 1 in 26 Americans will develop epilepsy at some point in life – more than will have autism, AIDS, or Parkinson’s disease. Some patients do fine between seizures and can function normally. In others, their brains are constantly being disrupted, like a radio station filled with static, according to Dr. Blaise Bourgeois the director of the Division of Epilepsy and Clinical Neurophysiology at Boston Children’s. © 2012 NY Times Co.

Keyword: Epilepsy
Link ID: 17156 - Posted: 08.13.2012

By SABRINA TAVERNISE Adolescents in states with strict laws regulating the sale of snacks and sugary drinks in public schools gained less weight over a three-year period than those living in states with no such laws, a new study has found. The study, published Monday in Pediatrics, found a strong association between healthier weight and tough state laws regulating food in vending machines, snack bars and other venues that were not part of the regular school meal programs. Such snacks and drinks are known as competitive foods, because they compete with school breakfasts and lunches. The conclusions are likely to further stoke the debate over what will help reduce obesity rates, which have been rising drastically in the United States since the 1980s. So far, very little has proved effective and rates have remained stubbornly high. About a fifth of American children are obese, according to the Centers for Disease Control and Prevention. Public health experts have urged local and state governments to remove competitive foods from schools, and in recent years states have started to pass laws that restrict their sale, either banning them outright or setting limits on the amount of sugar, fat or calories they contain. The study tracked weight changes for 6,300 students in 40 states between 2004 and 2007, following them from fifth to eighth grade. They used the results to compare weight change over time in states with no laws regulating such food against those in states with strong laws and those with weak laws. © 2012 The New York Times Company

Keyword: Obesity; Development of the Brain
Link ID: 17155 - Posted: 08.13.2012

By Karen Weintraub Dr. Steven E. Hyman, a neuroscientist and former Harvard provost, now directs the Stanley Center for Psychiatric Research at the Broad Institute, which is trying to better understand and develop treatments for conditions like depression, anxiety, schizophrenia, bipolar disorder, ADHD, obsessive-compulsive disorder, and autism. Q. There haven’t been a lot of drugs developed recently to treat these conditions. A. The modern era of neuropsychopharmacology began brilliantly in the early 1950s. There has been enormous progress in making drugs safer and more tolerable. [But effectiveness has not improved substantially.] We’ve reached a fairly unsatisfactory place in the treatment of these devastating illnesses. Q. Big drug companies are now getting out of the business of developing new medications for these conditions. A. The pharmaceutical industry is basically giving up and throwing in the towel. Their exit is both a symptom of the difficulty and a problem. Q. What does this mean for someone with one of these conditions? A. I don’t want to be inappropriately negative. If somebody has OCD or panic disorder or depression, the combination of cognitive behavioral therapy and a well chosen SSRI-like drug [like Prozac] will, for a reasonable fraction of those patients, markedly improve their lives, although there will be side effects and residual symptoms. © 2012 NY Times Co.

Keyword: Schizophrenia; OCD - Obsessive Compulsive Disorder
Link ID: 17154 - Posted: 08.13.2012

By KATIE HAFNER SEATTLE — Dr. Richard Wesley has amyotrophic lateral sclerosis, the incurable disease that lays waste to muscles while leaving the mind intact. He lives with the knowledge that an untimely death is chasing him down, but takes solace in knowing that he can decide exactly when, where and how he will die. Under Washington State’s Death With Dignity Act, his physician has given him a prescription for a lethal dose of barbiturates. He would prefer to die naturally, but if dying becomes protracted and difficult, he plans to take the drugs and die peacefully within minutes. “It’s like the definition of pornography,” Dr. Wesley, 67, said at his home here in Seattle, with Mount Rainier in the distance. “I’ll know it’s time to go when I see it.” Washington followed Oregon in allowing terminally ill patients to get a prescription for drugs that will hasten death. Critics of such laws feared that poor people would be pressured to kill themselves because they or their families could not afford end-of-life care. But the demographics of patients who have gotten the prescriptions are surprisingly different than expected, according to data collected by Oregon and Washington through 2011. Dr. Wesley is emblematic of those who have taken advantage of the law. They are overwhelmingly white, well educated and financially comfortable. And they are making the choice not because they are in pain but because they want to have the same control over their deaths that they have had over their lives. © 2012 The New York Times Company

Keyword: ALS-Lou Gehrig's Disease
Link ID: 17153 - Posted: 08.13.2012

by Krystnell A. Storr Imagine feeling like you’re lifting a 50-kilogram weight just by pulling at thin air. That’s just one of the possible applications of new "smart fingertips" created by a team of nanoengineers. The electronic fingers mold to the shape of the hand, and so far the researchers have shown that they can transmit electric signals to the skin. The team hopes to one day incorporate the devices into a smart glove that creates virtual sensations, fooling the brain into feeling everything from texture to temperature. Scientists have already developed circuits that stimulate our sense of touch. Some are used in Braille readers that allow blind people to browse the Internet. The devices work by sending electric currents to receptors in the skin, which interpret them as real sensations. However, most of these circuits are built on flat, rigid surfaces that can’t bend, stretch, or fold, says Darren Lipomi, a nanoengineer at the University of California, San Diego, who was not involved in the new study. Hoping to create circuits with the flexibility of skin, materials scientist John Rogers of the University of Illinois, Urbana-Champaign, and colleagues cut up nanometer-sized strips of silicon; implanted thin, wavy strips of gold to conduct electricity; and mounted the entire circuit in a stretchable, spider web-type mesh of polymer as a support. They then embedded the circuit-polyimide structure onto a hollow tube of silicone that had been fashioned in the shape of a finger. Just like turning a sock inside out, the researchers flipped the structure so that the circuit, which was once on the outside of the tube, was on the inside where it could touch a finger placed against it. © 2010 American Association for the Advancement of Science

Keyword: Pain & Touch; Robotics
Link ID: 17152 - Posted: 08.13.2012

By Eric Kandel Our attraction to faces, and particularly to eyes, appears to be innately determined. Infants as well as adults prefer to look at eyes rather than other features of a person’s face, and both infants and adults are sensitive to gaze. The direction of a person’s gaze is very important in our processing of the emotions displayed by that person’s face, because the brain combines information from gaze with information from facial expressions. Reginald Adams from Pennsylvania State University and Robert Kleck from Dartmouth College have found that a direct gaze and an expression of happy emotion facilitate the communication and processing of joy, friendliness, and approach-oriented emotions presumably because, as Uta Frith has found, only direct gaze recruits the dopaminergic reward system. In contrast, an averted, sad, or fearful gaze communicates the avoidance-oriented emotions of fear and sadness. Although gaze and facial expression are processed together, other aspects of beauty, such as gender and age, are processed independently. In a biological experiment designed to examine the neural correlates of beauty—that is, the mechanisms in our brain that account for our sense of beauty—John O’Doherty and his colleagues explored the role of the smile. They found that the orbitofrontal (ventrolateral) region of the prefrontal cortex, the region that is activated by reward and thought to be the apex of the representation of pleasure in the brain, is also activated by attractive faces. Moreover, the response of this region is enhanced by the presence of a smile. © 2012 Scientific American,

Keyword: Emotions; Vision
Link ID: 17151 - Posted: 08.13.2012

by Sara Reardon Freedom of information requests have revealed that pregnant women may not have been given all the facts before taking an experimental treatment to prevent female fetuses from being masculinised as a result of a rare genetic disorder. Research has provided some evidence that dexamethasone, a drug normally prescribed to relieve inflammation, can prevent girls with a rare hormonal disease from developing male genitalia and same-sex attraction if they are treated as fetuses. But as yet, no clinical studies show that this treatment is safe, says Alice Dreger of Northwestern University in Evanston, Illinois. She claims that researchers have misled an unknown number of pregnant women into taking the experimental treatment without properly informing them of its risks. Since the 1980s, Maria New of Mount Sinai School of Medicine in New York has studied and popularised the idea of prescribing dexamethasone "off-label" to women at risk of having foetuses with congenital adrenal hyperplasia (CAH). The treatment is now taught as standard practice in medical schools. But because the drug must be given very early in pregnancy before the fetus' gender or CAH status is known, many fetuses are treated unnecessarily. A child with two carrier parents has a one-in-four chance of having the disease, and the treatment only works for girls. There is little research available on the effects of dexamethasone, which mimics a steroid hormone. And because dexamethasone doesn't cure CAH but only prevents masculinisation of girls, it can be difficult to distinguish possible effects of the drug from other treatments the children receive after birth. © Copyright Reed Business Information Ltd.

Keyword: Hormones & Behavior; Sexual Behavior
Link ID: 17150 - Posted: 08.11.2012

By Tina Hesman Saey If variety lends life flavor, then humans are kicking things up to a previously unrecognized notch on the spice-o-meter. New efforts to decipher the genetic blueprints of thousands of people have turned up more than half a million tweaks in human DNA, many more than scientists expected. Most of these tweaks are new to science, and a majority fall into a class called “rare variants,” found in 0.5 percent of the population or less. Some of the variety recently uncovered is so uncommon that it shows up in people living in a single geographic region, or even in only one person. Despite their limited spread, the newly discovered rare variants could profoundly affect susceptibility to disease or how well drugs work. They may also help researchers reconstruct recent human migrations around the world. For years, scientists have been examining the chemical units of DNA called nucleotides that act as letters in the human genetic instruction book. So researchers thought they had a good handle on how often to expect single-letter changes in the A’s, G’s, T’s and C’s in that book. Such changes stem from errors in copying and are spotted via comparison with some majority-rule blueprint. They can go by terms like “single nucleotide polymorphisms” or “mutations” depending on where and when they show up. When looking at 202 genes predicted to be important in diseases from 14,002 people, John Novembre of the University of California, Los Angeles and colleagues unearthed five times as many rare genetic variants as expected. © Society for Science & the Public 2000 - 2012

Keyword: Genes & Behavior
Link ID: 17149 - Posted: 08.11.2012

Duncan Graham-Rowe A skull implant that can detect an epileptic seizure and deliver therapeutic electrical impulses can reduce the length of these events by 60% in rats. The device, tested on nine rats with a ‘petit mal’ form of epilepsy, is described today in Science1. Most electrical stimulation devices, such as those that deliver deep-brain stimulation (DBS) to treat Parkinson’s disease and depression, operate continuously, delivering impulses regardless of the patient’s brain activity. But this can cause a range of undesirable side effects, such as headaches. Seizure-responsive versions of DBS devices are coming to market, such as the Responsive Neurostimulator System developed by NeuroPace, based in Mountain View, California. The system is awaiting approval by the US Food and Drug Administration and will be aimed at adults with certain types of partial-onset seizures, which tend to be localized to certain regions of the brain. But as the name implies, DBS uses electrodes that penetrate the brain, which can also carry certain risks, such as a worsening of epilepsy symptoms. In the latest study, György Buzsáki, a neuroscientist at the New York University School of Medicine, and his colleagues used a less invasive approach that involves transcranial electrical stimulation (TES) of neurons using electrodes implanted in the skull. This technique has been shown to be effective at modifying the brain's cortical (outermost) neurons, which become abnormally excited during epileptic seizures. To detect the onset of a seizure, recording electrodes that detect neural activity were implanted on the brain's surface. © 2012 Nature Publishing Group,

Keyword: Epilepsy
Link ID: 17148 - Posted: 08.11.2012

By Cheryl Murphy Liliputs and little people, cartoon characters dancing on your desk, a civil war soldier in your living room, a zebra walking down the street. Typically not what we’d expect to see with our own eyes. But for some, it happens almost every day…for a year or so anyway. The “visions” aren’t always complex or bizarre. Sometimes they can “blend in” to our everyday lives a bit more. One case study was recently published in the Canadian Journal of Ophthalmology described a patient having visual hallucinations of small children popping up in her vision. She didn’t try to speak or interact with them in any way and they never spoke to her. She didn’t recognize them. She knew that they weren’t real and she wasn’t frightened of them but there they were. She saw them. Why? It turns out she had Charles Bonnet Syndrome, a condition in which visual hallucinations are caused by recent visual field loss… and, in her case, a brain tumor. People who have suffered newly acquired vision loss from eye conditions such as macular degeneration, diabetic retinopathy or cataracts (or from damage to other parts of the visual pathway in the brain) can have new visual field defects as a result and sometimes they begin to “see” things that really aren’t there. These people have no prior history of dementia or cognitive impairment, have never had any hallucinations in the past and are not taking medications known to have hallucinations as one of their side effects. Typically, no other sense (taste, touch, smell, or hearing) is affected in Charles Bonnet Syndrome other than sight. It can affect the young as well as the old in that there have been cases of Charles Bonnet Syndrome reported in young children who suffered vision loss from retinopathy of prematurity. In some cases, the vision loss is only to a part of their whole field of vision and their vision can sometimes remain as sharp as 20/40. © 2012 Scientific American,

Keyword: Vision; Attention
Link ID: 17147 - Posted: 08.11.2012

by Michael Marshall You may think you can cope without sleep, but you have nothing on male pectoral sandpipers. Some of these birds can go more than a fortnight with hardly any sleep – the most extreme case of uninduced sleep deprivation known in any animal. What's more, the males that sleep the least father the most offspring, suggesting they benefit from their lack of slumber. Pectoral sandpipers (Calidris melanotos) breed on the Arctic tundra of Asia and North America. Males don't help with childcare – instead they try to mate with as many females as possible. Bart Kempenaers of the Max Planck Institute for Ornithology in Seewiesen, Germany and colleagues fitted radio tags to 149 birds – accounting for most of a population living near Barrow in Alaska. This showed that males were highly active during periods when females were fertile. One male was active 95 per cent of the time for 19 days. The team then fitted 29 of the males with devices that recorded their brain activity, something never done before with a wild bird. This allowed them to look at the active males' sleep patterns. They found that the males that slept the least slept more deeply, but calculations show that this wouldn't make up for the sleep they missed, says team member Niels Rattenborg. © Copyright Reed Business Information Ltd

Keyword: Sleep; Sexual Behavior
Link ID: 17146 - Posted: 08.11.2012

by Chelsea Wald Some of our personality traits from childhood stick with us for the rest of our lives. An early shyness on the playground doesn't always go away in the boardroom, for example. But what if your entire body changed as you aged, transforming you into a completely unrecognizable creature? Would you retain the personality of your youth? A new study in frogs suggests that you would. In the past decade, scientists have shown that a broad range of animals—from dogs to sea anemones—display consistent personalities throughout their lives. Despite changes in their environment, individuals maintain their tendencies, such as being more or less active and exploratory, relative to other individuals of their species. But some researchers have theorized that animals that undergo metamorphosis should be exceptions. The full-body transformation, seen in everything from frogs to butterflies, dramatically alters every aspect of the animal—not only its shape, but also where it lives and what it needs to do to survive and reproduce. Why, then, shouldn't metamorphosis also change the animal's personality, so that strengths in larvae don't become flaws in adults? The relative restlessness that helps a caterpillar find food better than its peers, for instance, could get the butterfly into trouble with predators. Few researchers have attempted to study personality before and after metamorphosis, says behavioral ecologist Alexander Wilson of the Leibniz-Institute of Freshwater Ecology and Inland Fisheries in Berlin. He says his new study of frogs, to be published later this month in Behavioral Ecology, is the first to tackle the question in vertebrates. It was hard, Wilson says, to find personality tests that would work well for tadpoles and frogs, which are like two distinct animals. "[They] reach a certain stage of their life and then, bam! They change into something completely different." © 2010 American Association for the Advancement of Science

Keyword: Emotions; Evolution
Link ID: 17145 - Posted: 08.11.2012

ROBINS appear to have an eye for numbers, at least when it comes to choosing the biggest meal. "Discriminating between two large groups of objects that are close in number would be pretty exceptional for any animal or human, but that's exactly what the robins did," says Alexis Garland at Victoria University of Wellington in New Zealand. Garland let 36 wild North Island robins choose one of two wells after seeing different numbers of mealworms dropped en masse into each. Most picked the fuller well as long as the ratio was below 0.75 - correctly selecting, say, 64 over 32 worms. The mechanism at work here is called ratio-based representation and involves guessing which large group of items has the bigger bulk. The robins did even better when the worms were dropped into the wells one by one and covered so that the masses could not be compared: they managed a ratio of 0.88, albeit with a smaller number of worms. For the largest trial at this ratio - 14 versus 16 worms - most robins chose correctly (Animal Cognition, DOI: 10.1007/s10071-012-0537-3). Other animals tested like this have only managed to track about four items. Robins hide multiple food items in several places so it may be advantageous to distinguish more from less quickly, says Garland. © Copyright Reed Business Information Ltd.

Keyword: Intelligence; Evolution
Link ID: 17144 - Posted: 08.11.2012

By Rick Nauert PhD Senior News Editor Most of us take the ability to read and write for granted. For some, however, these fundamental skills are difficult to master. Sadly, factors associated with the variety of symptoms that contribute to a diagnosis of dyslexia have remained obscure. New research may change this picture as researchers announce a major advancement toward understanding the cause of dyslexia. Neuroscientist Begoña Díaz, Ph.D., and her colleagues at the Max Planck Institute for Human Cognitive and Brain Sciences in Leipzig, Germany, have discovered an important neural mechanism underlying dyslexia. They believe problems arise in the part of the brain called the medial geniculate body in the thalamus. Experts believe this discovery can provide the basis for developing potential treatments for the condition. People who suffer from dyslexia have difficulties with identifying speech sounds in spoken language. For example, while most children are able to recognize whether two words rhyme even before they go to school, dyslexic children often cannot do this until late primary school age. Most people suffer from dyslexia for their whole lives although many learn to compensate. Experts say that between five and 10 percent of children suffer from dyslexia, yet very little is known about its causes. © 1992-2012 Psych Central

Keyword: Dyslexia
Link ID: 17143 - Posted: 08.11.2012

By Stephanie Pappas Senior Writer Parrots can draw conclusions about where to find a food reward not only from clues as to its location, but also from the absence of clues — an ability previously only seen in humans and other apes. In a new study, researchers tested African Grey parrots on their reasoning abilities by shaking empty boxes and boxes filled with food so that the parrots could hear the snacks rattling around. To pick the box that would win them a treat, the parrots had to figure out that the sound indicated food and that a lack of sound from one box probably meant food in the other. It's a challenge that even human children can't reason through until about age 3. "It suggests that Grey parrots have some understanding of causality and that they can use this to reason about the world," study scientist Christian Schloegl, a researcher at the University of Vienna, told LiveScience. African Grey parrots are known to be clever, as are many other birds. In earlier studies with Grey parrots, researchers have shown them two opaque boxes, one full of food and one empty. When the parrots are shown that one box has no food in it, they almost always pick the second box in search of a treat. This could be because the parrots infer that if one box is empty, the other is likely full, Schloegl said. But researchers couldn't rule out that they were simply avoiding the empty box for some unknown reason. © 2012 NBCNews.com

Keyword: Intelligence; Evolution
Link ID: 17142 - Posted: 08.08.2012