Most Recent Links

Follow us on Facebook or subscribe to our mailing list, to receive news updates. Learn more.


Links 8281 - 8300 of 29407

Parrots can dance and talk, and now apparently they can use and share grinding tools. They were filmed using pebbles for grinding, thought to be a uniquely human activity – one that allowed our civilisations to extract more nutrition from cereal-based foods. Megan Lambert from the University of York, UK, and her colleagues were studying greater vasa parrots (Coracopsis vasa) in an aviary when they noticed some of the birds scraping shells in their enclosure with pebbles and date pips. “We were surprised,” says Lambert. “Using tools [to grind] seashells is something never seen before in animals.” Afterwards, the birds would lick the powder from the tool. Some of the parrots even passed tools to each other, which is rarely seen in animals. This behaviour was exclusively male to female. Lambert and her team, who watched the parrots for six months, noticed that the shell-scraping was more frequent before their breeding season. Since seashells contain calcium, which is critical for females before egg-laying, they suspect that the parrots could be manufacturing their own calcium supplements, as the mineral is probably better absorbed in powder form. Greater vasa parrots are native to Madagascar and have breeding and social systems unique among parrots. For example, two or more males have an exclusive sexual relationship with two or more females, and they are unusually tolerant of their group members. The reproductive ritual of sharing tools and grinding could be yet another one of their quirks. © Copyright Reed Business Information Ltd.

Keyword: Intelligence; Evolution
Link ID: 21707 - Posted: 12.16.2015

By Geoffrey S. Holtzman In November 1834, a 9-year-old boy named Major Mitchell was tried in Maine on one charge of maiming and one charge of felonious assault with intent to maim. He had lured an 8-year-old classmate into a field, beaten him with sticks, attempted to drown him in a stream, and castrated him with a piece of tin. Yet what makes this case so remarkable is neither the age of the defendant nor the violence of his crime, but the nature of his trial. Mitchell’s case marks the first time in U.S. history that a defendant’s attorney sought leniency from a jury on account of there being something wrong with the defendant’s brain. More recently, there has been an explosion in the number of criminals who have sought leniency on similar grounds. While the evidence presented by Mitchell’s defense was long ago debunked as pseudoscience (and was rightly dismissed by the judge), the case for exculpating Major Mitchell may actually be stronger today than it was 181 years ago. In a curious historical coincidence, recent advances in neuroscience suggest that there really might have been something wrong with Major Mitchell’s brain and that neurological deficits really could have contributed to his violent behavior. The case provides a unique window through which to view the relationship between 19th-century phrenology—the pseudoscientific study of the skull as an index of mental faculties—and 21st-century neuroscience. As you might expect, there is a world of difference between the two, but maintaining that difference depends crucially on the responsible use of neuroscience. Major Mitchell’s story cautions against overlooking neuroscience’s limitations, as well as its ability to be exploited for suspect purposes. © 2015 The Slate Group LLC.

Keyword: Emotions; Attention
Link ID: 21706 - Posted: 12.16.2015

Human memory is about to get supercharged. A memory prosthesis being trialled next year could not only restore long-term recall but may eventually be used to upload new skills directly to the brain – just like in the film The Matrix. The first trials will involve people with epilepsy. Seizures can sometimes damage the hippocampus, causing the brain to lose its ability to form long-term memories. To repair this ability, Theodore Berger at the University of Southern California and his colleagues used electrodes already implanted in people’s brains as part of epilepsy treatment to record electrical activity associated with memory. The team then developed an algorithm that could predict the neural activity thought to occur when a short-term memory becomes a long-term memory, as it passes through the hippocampus. Early next year, Berger’s team will use this algorithm to instruct the electrodes to predict and then mimic the activity that should occur when long-term memories are formed. “Hopefully, it will repair their long-term memory,” says Berger. Previous studies using animals suggest that the prosthesis might even give people a better memory than they could expect naturally. A similar approach could eventually be used to implant new memories into the brain. Berger’s team recorded brain activity in a rat that had been trained to perform a specific task. The memory prosthesis then replicated that activity in a rat that hadn’t been trained. The second rat was able to learn the task much faster than the first rat – as if it already had some memory of the task. © Copyright Reed Business Information Ltd.

Keyword: Learning & Memory; Robotics
Link ID: 21705 - Posted: 12.16.2015

Tina Hesman Saey SAN DIEGO — Friendly ghosts help muscles heal after injury. Connective tissue sheaths that bundle muscle cells together leave behind hollow fibers when muscles are injured, Micah Webster of the Carnegie Institution for Science in Baltimore and colleagues discovered. Muscle-repairing stem cells build new tissue from inside those empty tunnels, known as ghost fibers, Webster reported December 13 at the annual meeting of the American Society for Cell Biology. Researchers previously knew that stem cells can heal muscle, but how stem cells integrate new cells into muscle fibers has been a mystery. Webster and colleagues used a special microscopy technique to watch stem cells in live mice as the cells fixed muscles damaged by snake venom. Stem cells from undamaged parts of the muscle fiber crawled back and forth through the ghostly part of the fibers and spaced themselves out evenly. Stem cells replicated themselves to reconstruct each muscle fiber inside its ghostly shell the researchers found. Stem cells didn’t move from one ghost fiber to another. The finding suggests that researchers will need to create artificial ghost fibers to repair injuries in which chunks of muscles are lost, such as in soldiers hit by explosives, Webster said. The researchers also reported the results online December 10 in Cell Stem Cell. M.T. Webster et al. Intravital imaging reveals ghost fibers as architectural units guiding muscle progenitors. Annual meeting of the American Society for Cell Biology, San Diego, December 13, 2015. M.T. Webster et al. Intravital imaging reveals ghost fibers as architectural units guiding myogenic progenitors during regeneration. Cell Stem Cell. Published online December 10, 2015. doi: 10.1016/j.stem.2015.11.005 © Society for Science & the Public 2000 - 2015

Keyword: Muscles
Link ID: 21704 - Posted: 12.16.2015

By David Shultz As the Rolling Stones, Revlon, and Angelina Jolie can attest, not many body parts are more sexualized than the lips. A new study published online today in Royal Society Open Science, suggests that we’re not the only primates that feel this way. Black-and-white snub-nosed monkeys (Rhinopithecus bieti, pictured) have a strict social hierarchy in which a few, older males mate with multiple females, while the younger males form bachelor groups and bide their time. The males’ lips naturally redden with age, but the story seems a little more complicated than that: A series of photographs taken over multiple months shows that mating males’ lips redden during the mating season, whereas the bachelor males’ become paler. Scientists still aren’t sure why the animals’ lips seem to correspond with their social rank, but one idea is that females prefer the redder shades when choosing a mate, similar to how a female peacock chooses the male with the most elaborate tail. Another explanation could be that the males are using lip color as a preemptive indicator of their status in order to minimize conflict: Paler lips could make bachelors appear less threatening, allowing the mating males to focus their aggression on other red-lipped competitors. Both mechanisms could also be acting simultaneously, the authors say. © 2015 American Association for the Advancement of Science.

Keyword: Sexual Behavior
Link ID: 21703 - Posted: 12.16.2015

Jon Hamilton Taking antidepressants during the second or third trimester of pregnancy may increase the risk of having a child with autism spectrum disorder, according to a study of Canadian mothers and children published Monday in JAMA Pediatrics. But scientists not involved in the research say the results are hard to interpret and don't settle the long-running debate about whether expectant mothers with depression should take antidepressants. "This study doesn't answer the question," says Bryan King, program director of the autism center at Seattle Children's Hospital and a professor of psychiatry and behavioral sciences at the University of Washington. "My biggest concern is that it will be over-interpreted," says King, who wrote an editorial that accompanied the study. "It kind of leaves you more confused," says Alan Brown, a professor of psychiatry and epidemiology at Columbia University who studies risk factors for autism. "Mothers shouldn't get super worried about it," he says. One reason it's confusing is that there's strong evidence that mothers with depression are more likely than other women to have a child with autism, whether or not they take antidepressants during pregnancy. King and Brown say that makes it very hard to disentangle the effects of depression itself from those of the drugs used to treat it. © 2015 npr

Keyword: Depression; Autism
Link ID: 21702 - Posted: 12.15.2015

When anticonvulsant drugs fail to control epilepsy, surgery can be used as a last resort: removing the part of the brain thought to be the source of someone’s seizures. Unfortunately, this doesn’t always work. A computer model of brain activity could change things for the better by allowing surgeons to more precisely tailor the procedure to the individual. Seizures are caused by sudden surges in electrical activity in the brain. EEG scans made during a seizure can capture what is going on, providing a clue to the part of the brain that needs to be cut out. Even so, the surgery still fails to prevent seizures in 30 per cent of cases. There are other ways to track down the source of someone’s seizures, however. For example, the connectivity of the brain’s neurons and the surface area of affected regions is different in people with epilepsy compared with those who do not have the condition. Frances Hutchings at Newcastle University, UK and her colleagues have shown that these differences can be picked up using a combination of fMRI scans and diffusion tensor imaging (DTI). They used this data to model the brains of 22 people with epilepsy. By simulating the brain’s electrical activity, they were able to see where it went awry and identify the region where seizures were most likely to originate in each individual. © Copyright Reed Business Information Ltd.

Keyword: Epilepsy; Brain imaging
Link ID: 21701 - Posted: 12.15.2015

By Elizabeth Pennisi Imagine trying to train wild sea lions—without them ever seeing you. That was Peter Cook's challenge 8 years ago when he was trying to figure out whether poisonous algae were irrevocably damaging the animals’ brains. With a lot of patience and some luck, the comparative neuroscientist from Emory University in Atlanta has succeeded, and the news isn't good. Toxins from the algae mangle a key memory center, likely making it difficult for sick animals to hunt or navigate effectively, Cook and his colleagues report today. "Sea lions can be seen as sentinels of human health," says Kathi Lefebvre, a research biologist at the Northwest Fisheries Science Center in Seattle, Washington, who was not involved with the work. As oceans warm, toxic algae proliferate and cause so-called red tides because the water looks reddish. So "understanding these toxins in wild animals is going to become more important," she says. Red tides are produced by algae called diatoms. They make a toxin called domoic acid, which is consumed by other plankton that in turn become food for fish and other organisms. Predators such as anchovies, sardines, and other schooling fish accumulate this toxin in their bodies. So when algal populations explode, say, because of warming water, domoic acid concentrations increase in these animals to a point that they affect the sea lions that feast on them. Scientists first recognized this problem in 1998, after hundreds of sea lions were found stranded or disoriented along California's coast. Since then, researchers have studied sick and dead sea lions and documented that the toxin causes seizures and damages the brain, sometimes killing the animal. © 2015 American Association for the Advancement of Science.

Keyword: Learning & Memory; Neurotoxins
Link ID: 21700 - Posted: 12.15.2015

By SINDYA N. BHANOO Prairie voles are small Midwestern rodents known for monogamous behavior. But some males are also known to stray and seek out other females. A new study reports that mating preferences in the voles are linked to genetic differences, and that both monogamous and nonmonogamous males are readily found in nature. The study appears in the journal Science. Generally, animal neuroscientists believe that natural selection minimizes genetic variation. In this case, however, one mating strategy does not seem to be more successful than the other. Monogamous males stay near their nests, which ensures that female mates remain faithful. Promiscuous males have more partners, but they also lose sight of their own mates. “When you roam, your own female is free to mate with whoever she wants,” said Steven M. Phelps, a neurobiologist at the University of Texas at Austin and one of the study’s authors. The genetic differences between nonmonogramous and monogamous males affect a part of the brain important for spatial memory. Good memory may help a male keep track of his mate or keep him from returning to a hostile male’s territory. “We’ve shown for the first time that not only can brains be variable, but natural selection can keep that variability around,” Dr. Phelps said. © 2015 The New York Times Company

Keyword: Sexual Behavior; Evolution
Link ID: 21699 - Posted: 12.14.2015

The clock is ticking for Ronald Cohn. He wants to use CRISPR gene editing to correct the genes of his friend’s 13-year-old son. The boy, Gavriel, has Duchenne muscular dystrophy, a genetic disease in which muscles degenerate. Breathing and heart problems often start by the time people with the condition are in their early twenties. Life expectancy is about 25 years. By the standards of science, the field of CRISPR gene editing is moving at a lightning fast pace. Although the technique was only invented a few years ago, it is already being used for research by thousands of labs worldwide to make extremely precise changes to DNA. A handful of people have already been treated using therapies enabled by the technology, and last week an international summit effectively endorsed the idea of gene editing embryos. It is too soon to try the technique out, but the summit concluded that basic research on embryos should be permitted, alongside a debate on how we should use the technology. But for people like Cohn, progress can’t come fast enough. Gavriel was diagnosed at age 4. He has already lost the use of his legs but still has some movement in his upper body, and uses a manual wheelchair. Cohn, a clinician at the Hospital for Sick Children in Toronto, estimates that he has three years to develop and test a CRISPR-based treatment if he is to help Gavriel. Muscular dystrophy is caused by a faulty gene for the protein dystrophin, which holds our muscles together. Gavriel has a duplicated version of the gene. This week, Cohn’s team published a paper describing how they grew Gavriel’s cells in a dish and used CRISPR gene-editing techniques to snip out the duplication. With the duplication removed, his cells produced normal dystrophin protein. © Copyright Reed Business Information Ltd.

Keyword: Movement Disorders; Muscles
Link ID: 21698 - Posted: 12.14.2015

By C. CLAIBORNE RAY Q. We know that aquatic mammals communicate with one another, but what about fish? A. Fish have long been known to communicate by several silent mechanisms, but more recently researchers have found evidence that some species also use sound. It is well known that fish communicate by gesture and motion, as in the highly regimented synchronized swimming of schools of fish. Some species use electrical pulses as signals, and some use bioluminescence, like that of the firefly. Some kinds of fish also release chemicals that can be sensed by smell or taste. In 2011, a scientist in New Zealand suggested that what might be called fish vocalization has a role, at least in some ocean fish. In the widely publicized work, done for his doctoral thesis at the University of Auckland, Shahriman Ghazali recorded reef fish in the wild and in captivity, and found two dominant vocalizations, the croak and the purr, in choruses that lasted up to three hours, as well as a previously undescribed popping sound. The sounds of one species recorded in captivity — the bigeye, or Pempheris adspersa — carried 100 feet or more, and the researcher suggested it could be used to keep a group of fish together during nocturnal foraging. Another species, the bluefin gurnard, or Chelidonichthys kumu, was also very noisy, he found. “Vocalization” is a bit of a misnomer, as the sounds these fish make are produced by contracting and vibrating the swim bladder, not by using the mouth. © 2015 The New York Times Company

Keyword: Animal Communication; Hearing
Link ID: 21697 - Posted: 12.14.2015

By ALAN SCHWARZ Andrew Rios’s seizures began when he was 5 months old and only got worse. At 18 months, when an epilepsy medication resulted in violent behavior, he was prescribed the antipsychotic Risperdal, a drug typically used to treat schizophrenia and bipolar disorder in adults, and rarely used for children as young as 5 years. From Our Advertisers When Andrew screamed in his sleep and seemed to interact with people and objects that were not there, his frightened mother researched Risperdal and discovered that the drug was not approved, and had never even been studied, in children anywhere near as young as Andrew. “It was just ‘Take this, no big deal,’ like they were Tic Tacs,” said Genesis Rios, a mother of five in Rancho Dominguez, Calif. “He was just a baby.” Cases like that of Andrew Rios, in which children age 2 or younger are prescribed psychiatric medications to address alarmingly violent or withdrawn behavior, are rising rapidly, data shows. Many doctors worry that these drugs, designed for adults and only warily accepted for certain school-age youngsters, are being used to treat children still in cribs despite no published research into their effectiveness and potential health risks for children so young. Almost 20,000 prescriptions for risperidone (commonly known as Risperdal), quetiapine (Seroquel) and other antipsychotic medications were written in 2014 for children 2 and younger, a 50 percent jump from 13,000 just one year before, according to the prescription data company IMS Health. Prescriptions for the antidepressant fluoxetine (Prozac) rose 23 percent in one year for that age group, to about 83,000. The company’s data does not indicate how many children received these prescriptions (many children receive several prescriptions a year), but previous studies suggest that the number is at least 10,000. IMS Health researched the data at the request of The New York Times. © 2015 The New York Times Company

Keyword: Schizophrenia; Development of the Brain
Link ID: 21696 - Posted: 12.12.2015

The road map of conscious awareness has been deciphered. Now that we know which brain pathways control whether someone is awake or unconscious, we may be able to rouse people from a vegetative or minimally conscious state. In 2007, researchers used deep brain stimulation to wake a man from a minimally conscious state. It was quite remarkable, says Jin Lee at Stanford University in California. The 38-year-old had suffered a severe brain injury in a street mugging six years earlier. Before his treatment he was unable to communicate and had no voluntary control over his limbs. When doctors stimulated his thalamus – a central hub that sends signals all around the brain – his speech and movement gradually returned. However, attempts to treat other people in a similar way have failed. The problem lies with the crudeness of the technique. “Deep brain stimulation is done without much knowledge of how it actually alters the circuits in the brain,” says Lin. The technique involves attaching electrodes to the brain and using them to stimulate the tissue beneath. Unfortunately, the electrodes can also stimulate unintended areas, which means it is hard to work out exactly what is happening in people’s brains. “There are a lot of fibres and different cells in the thalamus and working out what was going on in the brain was very difficult,” says Lin. “So we wanted to figure it out.” © Copyright Reed Business Information Ltd.

Keyword: Consciousness; Brain imaging
Link ID: 21695 - Posted: 12.12.2015

By Andrea Anderson Mom's ovaries could hold clues to some autism cases, new research suggests—and this time it's not because of genetic vulnerabilities carried in her eggs. A new, large-scale study out of Sweden suggests that women with polycystic ovarian syndrome (PCOS)—an endocrine disorder that affects 5 to 10 percent of women of childbearing age—have an increased risk of giving birth to children with autism spectrum disorder (ASD). The Karolinska Institute's Renee Gardner, along with colleagues from Sweden and the U.S., tapped into a Swedish national population health database to look at potential ties between PCOS and ASD. As they reported online December 8 in Molecular Psychiatry, the team looked at 23,748 individuals with ASD and nearly 209,000 unaffected individuals, all born in Sweden between 1984 and 2007. Although identifying information about the individuals was removed, the researchers had access to information about their relationships to others in the database as well as documented diagnoses and use of health care services. The group found that ASD was 59 percent more prevalent in children born to women with PCOS—a relationship that was independent of PCOS complications such as increased neonatal distress or C-section delivery. This risk level is roughly comparable with that of having a father over age 50 (estimated to be 66 percent) but lower than it is in those with certain rare genetic syndromes or mutations. The authors of the analysis believe PCOS increases ASD risk in offspring to a greater extent than maternal infection, one of many factors previously implicated in autism. © 2015 Scientific American

Keyword: Autism; Hormones & Behavior
Link ID: 21694 - Posted: 12.12.2015

Call it the optimism fallacy. It’s widely thought that staying happy and stress-free helps keep you healthy. But a massive study on the link between mood and mortality suggests that happiness actually has no effect on death rates. Other research that has found the opposite must have been mixing up cause and effect, says epidemiologist Richard Peto of the University of Oxford. “It’s likely that being ill makes you unhappy, rather than the other way round.” The power of positive thinking has passed into folklore, helping to fuel a large self-help industry – not to mention people who like to post “inspirational” quotes on social media. Some cancer bloggers complain that common advice to “fight” their illness by staying cheerful can be unhelpful. “Forcing optimism may have its own negative consequences,” says Gayle Sulik, who writes the “Pink Ribbon Blues” blog. “The emotional work to display optimism when a person does not feel it may add to stress.” To find out if there is indeed a link, Peto’s team conducted surveys with more than 700,000 UK women. At the start, they were asked questions about their health and how happy and relaxed they felt. A year later, the questionnaire was resent to a random sample of the women. Their responses suggested that most still felt the same as they did the year before. Ten years later, after allowing for any initial disparities in health, there turned out to be no difference in death rates between those who saw their glass as half-full or half-empty. © Copyright Reed Business Information Ltd.

Keyword: Emotions; Neuroimmunology
Link ID: 21693 - Posted: 12.12.2015

Laura Sanders You can thank your parents for your funny-looking hippocampus. Genes influence the three-dimensional shape of certain brain structures, scientists report in a paper posted online December 1 at bioRxiv.org. Showing a new way that genes help sculpt the brain opens up more ways to explore how the brain develops and operates. Earlier work linked genes to simple measurements of brain structures, such as overall volume or length. The new work goes beyond that by mathematically analyzing complex 3-D shapes and tying those shapes to a particular genetic makeup. A team led by researchers at Massachusetts General Hospital and Harvard Medical School analyzed MRI brain scans and genome data from 1,317 healthy young adults. Particular genetic profiles influenced the 3-D shape of structures including the hippocampus, caudate and cerebellum, the scientists found. In some brains, for instance, genes played a role in making the seahorse-shaped right hippocampus skinnier on the top and wider on the bottom. Genes also influenced whether the tail of the caudate was short or long. Quirks of brain structure shapes might play a role in disorders such as schizophrenia, autism spectrum disorder and bipolar disorder, which are known to be influenced by genes, the authors write. Citations T. Ge et al. Heritability of neuroanatomical shape. bioRxiv.org. Posted December 1, 2015. doi: 10.1101/033407. © Society for Science & the Public 2000 - 2015

Keyword: Genes & Behavior; Development of the Brain
Link ID: 21692 - Posted: 12.12.2015

By Karen Weintraub Is sleep induced by a benzodiazepine counted as restorative sleep? Researchers hate to admit it, but they don’t know enough about sleep to answer this question. Their best guess, several experts said, is that sleep is sleep. Dr. John Weyl Winkelman, a sleep disorders expert at Massachusetts General Hospital and Harvard Medical School, said if a patient asked him whether medicated sleep was restorative, “I’d say: ‘You tell me.’” There is quite a bit of evidence about the negative health consequences of insomnia, but researchers don’t know precisely what it is in the brain and body that is "restored" by sleep to aid optimal function. And it is unlikely that any specific stage of sleep is uniquely restorative, said Dr. Daniel J. Buysse, a sleep medicine expert and professor of psychiatry at the University of Pittsburgh. More sleep, less interrupted sleep, and sleep at the right time of night are all likely to be important, he said. There are two types of sleep: REM, when people dream, and non-REM, which has light, medium and deep portions. Sleeping pills mainly increase the amount of medium-depth non-REM sleep, Dr. Buysse said. Medications can help people fall asleep faster and reduce nighttime wakefulness, he said, and those changes are usually considered to contribute to restorative sleep. But different people respond differently. “Do you feel more rested, more alert, more able to concentrate, less irritable on medication versus off?" Dr. Buysse said. "If all those things are true then I would say it’s more restorative. If a hypnotic drug leaves you feeling hung over or more anxious, if it causes you to order five hickory smoked turkeys on the Internet without remembering, then it’s probably not good.” © 2015 The New York Times Company

Keyword: Sleep
Link ID: 21691 - Posted: 12.12.2015

Sara Reardon Manipulating brain circuits with light and drugs can cause ripple effects that could muddy experimental results. In the tightly woven networks of the brain, tugging one neuronal thread can unravel numerous circuits. Because of that, the authors of a paper1 published in Nature on 9 December caution that techniques such as optogenetics — activating neurons with light to control brain circuits — and manipulation with drugs could lead researchers to jump to unwarranted conclusions. In work with rats and zebra finches, neuroscientist Bence Ölveczky of Harvard University in Cambridge, Massachusetts, and his team found that stimulating one part of the brain to induce certain behaviours might cause other, unrelated parts to fire simultaneously, and so make it seem as if these circuits are also involved in the behaviour. According to Ölveczky, the experiments suggest that although techniques such as optogenetics may show that a circuit can perform a function, they do not necessarily show that it normally performs that function. “I don’t want to say other studies have been wrong, but there is a danger to overinterpreting,” he says. Ölveczky and his colleagues discovered these discrepancies by chance while studying rats that they had trained to press a lever in a certain pattern. They injected a drug called muscimol, which temporarilty shuts off neurons, into a part of the motor cortex that is involved in paw movement. The animals were no longer able to perform the task, which might be taken as evidence that neurons in this brain region were necessary to its performance. © 2015 Nature Publishing Group

Keyword: Brain imaging
Link ID: 21690 - Posted: 12.10.2015

By Darold A. Treffert The headlines read “New study suggests autism can be outgrown”, or “outgrowing autism: a doctor’s surprise and wonder.” The stories are based on studies reporting that 7-9% of children with a documented early autistic syndrome disorder (ASD) have no symptoms of the disorder on follow-up later in childhood or adolescence. That is good news. The question is how to account for it. Is it possible to simply “outgrow” autism? Was the initial diagnosis wrong? Did some interventions work? Or might there be other explanations for this welcome news? "In an earlier column titled “Oops. When “autism” isn’t autistic disorder,” I outlined three types of hyperlexia, or precocious reading ability, which is sometimes an element of a diagnosis of ASD. Type 1 are neurotypical children who simply read way ahead of their chronological age. Listening to a 4 year old reading books to his or her nursery school classmates is a startling experience. Type 2 are children in which intense fascination with letters and numbers, along with early reading and remarkable memory represent ‘splinter skills’ as a part of autistic syndrome disorder (ASD) Type 3 are children who likewise show intense fascination and preoccupation with numbers and letters very early, along with precocious reading skills and remarkable memory. They do have “autistic-like” symptoms or behaviors but those disappear over time as the child gets older. The outcome in these children is much more positive than those with ASD to their benefit and the great relief of their parents. Following the “Oops” article I received numerous reports from parents who identified with hyperlexia 3. “You just described my child,” the puzzled, and relieved parents would write as they read the case examples in my Wisconsin Medical Journal article in December, 2011. © 2015 Scientific American

Keyword: Autism
Link ID: 21689 - Posted: 12.10.2015

By Gretchen Reynolds Physical fitness may be critical for maintaining a relatively youthful and nimble brain as we age, according to a new study of brain activation patterns in older people. For most of us, our bodies begin to lose flexibility and efficiency as we enter our 40s. Running and other movements slow down and become more awkward, and something similar seems to occur within our heads. As middle age encroaches, our thinking becomes less efficient. We don’t toggle between mental tasks as nimbly as we once did or process new information with the same aplomb and clarity. Recently, neuroscientists have begun to quantify how those cognitive changes play out in our brains, to disquieting effect. In studies comparing brain activation in young people with that of people past 40, they have found notable differences, especially during mental tasks that require attention, problem solving, decision-making and other types of high-level thinking. Such thinking primarily involves activation of the brain’s prefrontal cortex. In young people, activation in the cortex during these cognitive tasks tends to be highly localized. Depending on the type of thinking, young people’s brains light up almost exclusively in either the right or left portion of the prefrontal cortex. But in older people, studies show, brain activity during the same mental tasks requires far more brainpower. They typically display activity in both hemispheres of their prefrontal cortex. In effect, they require more of their brains’ resources to complete the same tasks that young people do with less cognitive effort. Neuroscientists coined an acronym for this phenomenon: Harold, for hemispheric asymmetry reduction in older adults. Most agree that it represents a general reorganization and weakening of the brain’s function with age. © 2015 The New York Times Company

Keyword: Alzheimers; Development of the Brain
Link ID: 21688 - Posted: 12.10.2015