Chapter 13. Memory, Learning, and Development
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Researchers striving to understand the origins of dementia are building the case against a possible culprit: lead exposure early in life. A study spanning 23 years has now revealed that monkeys who drank a lead-rich formula as infants later developed tangles of a key brain protein, called tau, linked to Alzheimer's disease. Though neuroscientists say more work is needed to confirm the connection, the research suggests that people exposed to lead as children—as many in America used to be before it was eliminated from paint, car emissions, water, and soil—could have an increased risk of the common, late-onset form of Alzheimer’s disease. Even in small doses, lead can wreak havoc on the heart, intestines, kidneys, and nervous system. Children are especially prone to its pernicious effects, as it curbs brain development. Many studies have linked early lead exposure with lower IQs. Researchers estimate that one in 38 children in the United States still have harmful levels of the metal in their systems, but evidence linking this exposure to dementia later in life has been tenuous. A team led by toxicologist Nasser Zawia, however, has vigorously pursued the lead hypothesis. In one early study, from 2008, the group showed that plaques, insoluble globs of a protein called β-amyloid, marred the brains of five macaques that had consumed a lead-enriched formula as infants. The researchers had compared the preserved brain tissues from those macaques, sacrificed in 2003 at age 23 in a National Institutes of Health lab, with four similarly aged monkeys who had had lead-free formula. The amyloid plaques closely resembled those in the brains of adults with Alzheimer's disease that are thought to contribute to the dementia. © 2013 American Association for the Advancement of Science.
Many physicians and parents report that their autistic children have unusually severe gastrointestinal problems, such as chronic constipation or diarrhea. These observations have led some researchers to speculate that an ailing gut contributes to the disorder in some cases, but scientific data has been lacking. Now, a provocative study claims that a probiotic treatment for gastrointestinal issues can reduce autismlike symptoms in mice and suggests that this treatment could work for humans, too. The reported incidence of gut maladies in people with autism varies wildly between published studies—from zero to more than 80%—making it difficult to establish just how commonly the two conditions go together, says principal investigator Sarkis Mazmanian, a microbiologist at the California Institute of Technology (Caltech) in Pasadena. Overall, however, the evidence seems to point toward a connection. Last year, for example, a Centers for Disease Control and Prevention study of thousands of children with developmental disabilities found that kids with autism were twice as likely as children with other types of disorders to have frequent diarrhea or colitis, an inflammation of the large intestine. For many years, Mazmanian and his and colleagues have been studying the effects of a nontoxic strain of the bacterium Bacteroides fragilis on diseases such as Crohn's disease, which causes intestinal inflammation and allows potentially harmful substances that should pass out of the body to leak through junctions between cells that are normally tight. Although the researchers don’t understand the mechanism, the bacterium appears to restore the damaged gut, possibly by helping close these gaps. © 2013 American Association for the Advancement of Science.
Link ID: 19009 - Posted: 12.06.2013
By Dana Smith Daniel Tammet has memorized Pi to the 22,514th digit. He speaks ten different languages, including one of his own invention, and he can multiply enormous sums in his head within a matter of seconds. However, he is unable to hold down a standard 9-to-5 job, in part due to his obsessive adherence to ritual, down to the precise times he has his tea every day. Daniel is a savant. He is also autistic. And he is a synesthete. Daniel experiences numbers as having color, as well as shape and texture. This helps him perform amazing mathematical feats seemingly without effort, the answer simply materializing to him rather than having to calculate it out. In an interview he gave with The Guardian, Daniel explained, “When I multiply numbers together, I see two shapes. The image starts to change and evolve, and a third shape emerges. That’s the answer. It’s mental imagery. It’s like maths without having to think.” Clearly this man has an extraordinary brain. However, Daniel is perhaps not entirely unique, and it appears that the link between autism and synesthesia is more common than originally thought. This suggests that there is a potential common mechanism between these two conditions, which may even help to explain some of Daniel’s special savant abilities. A new study published in the journal Molecular Autism from a team of researchers at the University of Cambridge now empirically shows that there is an almost three-fold higher occurrence of synesthesia in individuals with autism (18.9%), compared with that of the general population (7.2%). This increased prevalence implies that there is indeed a significant link between autism and synesthesia. © 2013 Scientific American
Link ID: 19008 - Posted: 12.06.2013
By CARL ZIMMER Scientists have found the oldest DNA evidence yet of humans’ biological history. But instead of neatly clarifying human evolution, the finding is adding new mysteries. In a paper in the journal Nature, scientists reported Wednesday that they had retrieved ancient human DNA from a fossil dating back about 400,000 years, shattering the previous record of 100,000 years. The fossil, a thigh bone found in Spain, had previously seemed to many experts to belong to a forerunner of Neanderthals. But its DNA tells a very different story. It most closely resembles DNA from an enigmatic lineage of humans known as Denisovans. Until now, Denisovans were known only from DNA retrieved from 80,000-year-old remains in Siberia, 4,000 miles east of where the new DNA was found. The mismatch between the anatomical and genetic evidence surprised the scientists, who are now rethinking human evolution over the past few hundred thousand years. It is possible, for example, that there are many extinct human populations that scientists have yet to discover. They might have interbred, swapping DNA. Scientists hope that further studies of extremely ancient human DNA will clarify the mystery. “Right now, we’ve basically generated a big question mark,” said Matthias Meyer, a geneticist at the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, and a co-author of the new study. Hints at new hidden complexities in the human story came from a 400,000-year-old femur found in a cave in Spain called Sima de los Huesos (“the pit of bones” in Spanish). The scientific team used new methods to extract the ancient DNA from the fossil. “This would not have been possible even a year ago,” said Juan Luis Arsuaga, a paleoanthropologist at Universidad Complutense de Madrid and a co-author of the paper. © 2013 The New York Times Company
People with dementia who exercise improve their thinking abilities and everyday life, a body of medical research concludes. The Cochrane Collaboration carried out a systematic review of eight exercise trials involving more than 300 patients living at home or in care. Exercise did little for patients' moods, the research concluded. But it did help them carry out daily activities such as rising from a chair, and boosted their cognitive skills. Whether these benefits improve quality of life is still unclear, but the study authors say the findings are reason for optimism. Dementia affects some 800,000 people in the UK. And the number of people with the condition is steadily increasing because people are living longer. It is estimated that by 2021, the number of people with dementia in the UK will have increased to around one million. With no cure, ways to improve the lives of those living with the condition are vital. Researcher Dorothy Forbes, of the University of Alberta, and colleagues who carried out the Cochrane review, said: "Clearly, further research is needed to be able to develop best practice guidelines to enable healthcare providers to advise people with dementia living at home or in institutions. "We also need to understand what level and intensity of exercise is beneficial for someone with dementia." BBC © 2013
Link ID: 18999 - Posted: 12.05.2013
By James Gallagher Health and science reporter, BBC News The number of people living with dementia worldwide is set to treble by 2050, according to a new analysis. Alzheimer's Disease International says 44 million people live with the disease, but that figure will increase to 135 million by 2050. The figures were released ahead of the G8 dementia summit in London next week. In the UK, dementia research receives one eighth of the amount of funding that is spent on cancer, which charities say is insufficient. Alzheimer's Disease International expects increasing life expectancies to drive a surge in cases in poor and middle-income countries, particularly in South East Asia and Africa. Currently 38% of cases are in rich countries. But that balance is predicted shift significantly by 2050, with 71% of patients being in poor and middle-income countries. The report says most governments are "woefully unprepared for the dementia epidemic". Marc Wortmann, the executive director at Alzheimer Disease International, said: "It's a global epidemic and it is only getting worse - if we look into the future the numbers of elderly people will rise dramatically." Jeremy Hughes, chief executive of the UK's Alzheimer's Society, said: "Dementia is fast becoming the biggest health and social care challenge of this generation. "We must tackle dementia now, for those currently living with the condition across the world and for those millions who will develop dementia in the future. BBC © 2013
Link ID: 18998 - Posted: 12.05.2013
By PAM BELLUCK Scientists have been eager to see if oxytocin, which plays a role in emotional bonding, trust and many biological processes, can improve social behavior in people with autism. Some parents of children with autism have asked doctors to prescribe it, although it is not an approved treatment for autism, or have purchased lower-dose versions of the drug over the counter. Scientifically, the jury is out, and experts say parents should wait until more is known. Some studies suggest that oxytocin, sometimes called the “love hormone,” improves the ability to empathize and connect socially, and may decrease repetitive behaviors. Others find little or no impact, and some research suggests that it can promote clannish and competitive feelings, or exacerbate symptoms in people already oversensitive to social cues. Importantly, nobody knows if oxytocin is safe or desirable to use regularly or long term. Now, the first study of how oxytocin affects the brains of children with autism finds hints of promise — and also suggestions of what its limitations might be. On the promising side, the small study, published Monday in The Proceedings of the National Academy of Sciences, found that the hormone, given as an inhalant, generated increased activity in parts of the brain involved in social connection. This suggests not only that oxytocin can stimulate social brain areas, but also that in children with autism these brain regions are not irrevocably damaged but are plastic enough to be influenced. The limitations could include a finding that oxytocin prompted greater brain activity in children with the least severe autism. Some experts said that this could imply that oxytocin may work primarily in less-impaired people, but others said it might simply suggest that different doses are needed. © 2013 The New York Times Company
by Laura Sanders Last Sunday, the Giants battled the Redskins in our living room, and there was no bigger fan than 9-month-old Baby V. Unlike her father, she was not interested in RG3’s shortcomings. The tiny, colorful guys running around on a bright green field, the psychedelic special effects and the bursts of noise drew her in like a moth to a 42-inch high-definition flame. My friends with kids have noticed the same screen fascination in their little ones. Like adults, kids love colorful, shiny, moving screens. The problem, of course, is that watching TV probably isn’t the best way for little kids to spend their time. Long bouts in front of the tube have been linked to obesity, weaker attention spans and aggression in kids. Now, a new study of Japanese children has linked TV time with changes in the growing brains, effects that have been harder to spot. And the more television a kid watches, the more profound the brain differences, scientists report November 20 in Cerebral Cortex. Researchers studied kids between age 5 and 18 who watched between zero and four hours of television a day. On average, the kids watched TV for about two hours a day. Brain scans revealed that the more television a kid watched, the larger certain parts of the brain were. Gray matter volume was higher in regions toward the front and side of the head in kids who watched a lot of TV. Say that again? Watching television boosts brain volume? Before you rejoice and fire up Season 1 of Breaking Bad, keep in mind: Bigger isn’t always better. In this case, higher brain volume in these kids was associated with a lower verbal IQ. Study coauthor Hikaru Takeuchi Tohoku University in Japan says that these brain areas need to be pruned during childhood to operate efficiently. © Society for Science & the Public 2000 - 2013.
by Bob Holmes Dying cells may play only a small role in the brain decline that accompanies ageing. That is the suggestion from the first computer simulation of brain function that can solve intelligence tests almost as well as university undergraduates. The model promises to reveal how our brains and behaviour are affected by age, and might even offer a way of testing drugs that compensate for cognitive decline. Psychologists have known for many years that our ability to think through novel problems – our "fluid intelligence" – gradually declines with age. However, the reasons for this decline aren't clear, because many features of the brain change as we age: neurons die; connections become sparser between regions of the brain and between individual brain cells; and our mental representation of different concepts becomes less distinct, among other changes. So far, psychologists have been unable to tease apart these possible explanations for cognitive decline. Enter Chris Eliasmith, a theoretical neuroscientist at the University of Waterloo in Ontario, Canada, and his student Daniel Rasmussen. The pair used a computer to simulate the behaviour of about 35,000 individual brain cells wired together in a biologically realistic way. Just like a real brain, their model encoded information as a pattern of electrical activity in particular sets of cells. The researchers set up the system to solve a widely used intelligence test known as Raven's Progressive Matrices, which involves predicting what abstract symbol comes next in a sequence. © Copyright Reed Business Information Ltd.
By KRISTIN WARTMAN THE solution to one of America’s most vexing problems — our soaring rates of obesity and diet-related diseases — may have its roots in early childhood, and even in utero. Researchers at the Monell Chemical Senses Center, a nonprofit research organization in Philadelphia, have found that babies born to mothers who eat a diverse and varied diet while pregnant and breast-feeding are more open to a wide range of flavors. They’ve also found that babies who follow that diet after weaning carry those preferences into childhood and adulthood. Researchers believe that the taste preferences that develop at crucial periods in infancy have lasting effects for life. In fact, changing food preferences beyond toddlerhood appears to be extremely difficult. “What’s really interesting about children is, the preferences they form during the first years of life actually predict what they’ll eat later,” said Julie Mennella, a biopsychologist and researcher at the Monell Center. “Dietary patterns track from early to later childhood but once they are formed, once they get older, it’s really difficult to change — witness how hard it is to change the adult. You can, but it’s just harder. Where you start, is where you end up.” This may have profound implications for the future health of Americans. With some 70 percent of the United States population now overweight or obese and chronic diseases skyrocketing, many parents who are eating a diet high in processed, refined foods are feeding their babies as they feed themselves, and could be setting their children up for a lifetime of preferences for a narrow range of flavors. The Monell researchers have identified several sensitive periods for taste preference development. One is before three and a half months of age, which makes what the mother eats while pregnant and breast-feeding so important. “It’s our fundamental belief that during evolution, we as humans are exposed to flavors both in utero and via mother’s milk that are signals of things that will be in our diets as we grow up and learn about what flavors are acceptable based on those experiences,” said Gary Beauchamp, the director of the Monell Center. © 2013 The New York Times Company
Ewen Callaway Certain fears can be inherited through the generations, a provocative study of mice reports1. The authors suggest that a similar phenomenon could influence anxiety and addiction in humans. But some researchers are sceptical of the findings because a biological mechanism that explains the phenomenon has not been identified. According to convention, the genetic sequences contained in DNA are the only way to transmit biological information across generations. Random DNA mutations, when beneficial, enable organisms to adapt to changing conditions, but this process typically occurs slowly over many generations. Yet some studies have hinted that environmental factors can influence biology more rapidly through 'epigenetic' modifications, which alter the expression of genes, but not their actual nucleotide sequence. For instance, children who were conceived during a harsh wartime famine in the Netherlands in the 1940s are at increased risk of diabetes, heart disease and other conditions — possibly because of epigenetic alterations to genes involved in these diseases2. Yet although epigenetic modifications are known to be important for processes such as development and the inactivation of one copy of the X-chromsome in females, their role in the inheritance of behaviour is still controversial. Kerry Ressler, a neurobiologist and psychiatrist at Emory University in Atlanta, Georgia, and a co-author of the latest study, became interested in epigenetic inheritance after working with poor people living in inner cities, where cycles of drug addiction, neuropsychiatric illness and other problems often seem to recur in parents and their children. “There are a lot of anecdotes to suggest that there’s intergenerational transfer of risk, and that it’s hard to break that cycle,” he says. © 2013 Nature Publishing Group
by Jessica Griggs HAVING type 2 diabetes may mean you are already on the path to Alzheimer's. This startling claim comes from a study linking the two diseases more intimately than ever before. There is some good news: the same research also offers a way to reverse memory problems associated with diabetes – albeit in rats – which may hint at a new treatment for Alzheimer's. "Perhaps you should use Alzheimer's drugs at the diabetes stage to prevent cognitive impairment in the first place," says Ewan McNay from the University at Albany in New York. Alzheimer's cost the US $130 billion in 2011 alone. One of the biggest risk factors is having type 2 diabetes. This kind of diabetes occurs when liver, muscle and fat cells stop responding efficiently to insulin, the hormone that tells them to absorb glucose from the blood. The illness is usually triggered by eating too many sugary and high-fat foods that cause insulin to spike, desensitising cells to its presence. As well as causing obesity, insulin resistance can also lead to cognitive problems such as memory loss and confusion. In 2005, a study by Susanne de la Monte's group at Brown University in Providence, Rhode Island, identified a reason why people with type 2 diabetes had a higher risk of developing Alzheimer's. In this kind of dementia, the hippocampus, a part of the brain involved in learning and memory, seemed to be insensitive to insulin. Not only could your liver, muscle and fat cells be "diabetic" but so it seemed, could your brain. © Copyright Reed Business Information Ltd.
By Tanya Lewis 20 hours ago To understand the human brain, scientists must start small, and what better place than the mind of a worm? The roundworm Caenorhabditis elegans is one of biology's most widely studied organisms, and it's the first to have the complete wiring diagram, or connectome, of its nervous system mapped out. Knowing the structure of the animal's connectome will help explain its behavior, and could lead to insights about the brains of other organisms, scientists say. "You can't understand the brain without understanding the connectome," Scott Emmons, a molecular geneticist at Albert Einstein College of Medicine of Yeshiva University in New York, said in a talk earlier this month at the annual meeting of the Society for Neuroscience in San Diego. In 1963, South African biologist Sydney Brenner of the University of Cambridge decided to use C. elegans as a model organism for developmental biology. He chose the roundworm because it has a simple nervous system, it's easy to grow in a lab and its genetics are relatively straightforward. C. elegans was the first multicellular organism to have its genome sequenced, in 1998. Brenner knew that to understand how genes affect behavior, "you would have to know the structure of the nervous system," Emmons told LiveScience.
by Bethany Brookshire Most people take it as a given that distraction is bad for — oh, hey, a squirrel! Where was I? … Right. Most people take it as a given that distraction is bad for memory. And most of the time, it is. But under certain conditions, the right kind of distraction might actually help you remember. Nathan Cashdollar of University College London and colleagues were looking at the effects of distraction on memory in memory-impaired patients. They were specifically looking at distractions that were totally off-topic from a particular task, and how those distractions affected memory performance. Their results were published November 27 in the Journal of Neuroscience. The researchers worked with a small group of people with severe epilepsy who had lesions in the hippocampus, and therefore had memory problems. They compared them to groups of people with epilepsy without lesions, young healthy people, and older healthy people that were matched to the epilepsy group. Each of the participants went through a memory task called “delayed match-to-sample.” For this task, participants are given a set of samples or pictures, usually things like nature scenes. Then there’s a delay, from one second at the beginning of the test on up to nearly a minute. Then participants are shown another nature scene. Is it one they have seen before? Yes or no? The task starts out simply, with only one nature scene to match, but soon becomes harder, with up to five pictures to remember, and a five-second delay. People with memory impairments did a lot worse when they had more items to remember (called high cognitive load), falling off very steeply in their performance. Normal controls did better, still remaining fairly accurate, but making mistakes once in a while. © Society for Science & the Public 2000 - 2013.
By Neuroskeptic Claims that children with autism have abnormal brain white matter connections may just reflect the fact that they move about more during their MRI scans. So say a team of Harvard and MIT neuroscientists, including Nancy “Voodoo Correlations” Kanwisher, in a new paper: Spurious group differences due to head motion in a diffusion MRI study. Essentially, the authors show how head movement during a diffusion tensor imaging (DTI) scan causes apparant differences in the integrity of white matter tracts, like these ones: In comparisons of two randomized groups of healthy children – in whom no white matter differences ought to appear – spurious effects were seen whenever one group moved more than the other: As for autism, the authors found that kids with autism moved more, on average, than controls, and that matching the two groups by motion reduced the magnitude of the group differences in white matter (though many remained significant). Technically, the motion-related differences manifested as increases in RD and reductions in FA; these were localized: The pathways that exhibited the most substantial motion-induced group differences in our data were the corpus callosum and the cingulum bundle. Perhaps this is related to their proximity to non-brain voxels (such as the ventricles) … deeper brain areas appear to be more affected than more superﬁcial ones, thus distance from the head coils may also be a factor. The good news is that there’s a simple fix: entering the motion parameters, extracted from the DTI data itself, as a covariate in the analysis. The authors show that this is extremely effective. The bad news is that most researchers don’t do this.
By James Gallagher Health and science reporter, BBC News Steroids given to help premature babies develop may also be slightly increasing the risk of mental health disorders, say researchers. The drugs are often given to pregnant mothers at risk of a premature birth to help the baby's lungs prepare for life outside the womb. The study, in the journal PLoS One, showed there was a higher risk of attention disorders at age eight. The charity Bliss said it reinforced the need for regular health checks. Being born too soon can lead to long-term health problems and the earlier the birth the greater the problems. One immediate issue is the baby's lungs being unprepared to breathe air. Steroids can help accelerate lung development. However, the study by researchers at Imperial College London and the University of Oulu in Finland showed the drugs may also be affecting the developing brain. They compared what happened to 37 premature children whose mother was injected with steroids with 185 premature children, of the same weight and gestational age, who were not exposed to the extra dose of steroid. When the children were followed to the age of eight, there was a higher incidence of attention deficit hyperactivity disorder. No difference could be detected at age 16, but this may have been due to the small size of the study. BBC © 2013
One afternoon in October 2005, neuroscientist James Fallon was looking at brain scans of serial killers. As part of a research project at UC Irvine, he was sifting through thousands of PET scans to find anatomical patterns in the brain that correlated with psychopathic tendencies in the real world. “I was looking at many scans, scans of murderers mixed in with schizophrenics, depressives and other, normal brains,” he says. “Out of serendipity, I was also doing a study on Alzheimer’s and as part of that, had brain scans from me and everyone in my family right on my desk.” “I got to the bottom of the stack, and saw this scan that was obviously pathological,” he says, noting that it showed low activity in certain areas of the frontal and temporal lobes linked to empathy, morality and self-control. Knowing that it belonged to a member of his family, Fallon checked his lab’s PET machine for an error (it was working perfectly fine) and then decided he simply had to break the blinding that prevented him from knowing whose brain was pictured. When he looked up the code, he was greeted by an unsettling revelation: the psychopathic brain pictured in the scan was his own. Many of us would hide this discovery and never tell a soul, out of fear or embarrassment of being labeled a psychopath. Perhaps because boldness and disinhibition are noted psychopathic tendencies, Fallon has gone all in towards the opposite direction, telling the world about his finding in a TED Talk, an NPR interview and now a new book published last month, The Psychopath Inside. In it, Fallon seeks to reconcile how he—a happily married family man—could demonstrate the same anatomical patterns that marked the minds of serial killers. “I’ve never killed anybody, or raped anyone,” he says. “So the first thing I thought was that maybe my hypothesis was wrong, and that these brain areas are not reflective of psychopathy or murderous behavior.”
Medical marijuana can alleviate pain and nausea, but it can also cause decreased attention span and memory loss. A new study in mice finds that taking an over-the-counter pain medication like ibuprofen may help curb these side effects. "This is what we call a seminal paper," says Giovanni Marsicano, a neuroscientist at the University of Bordeaux in France who was not involved in the work. If the results hold true in humans, they "could broaden the medical use of marijuana," he says. "Many people in clinical trials are dropping out from treatments, because they say, ‘I cannot work anymore. I am stoned all the time.’ ” People have used marijuana for hundreds of years to treat conditions such as chronic pain, multiple sclerosis, and epilepsy. Studies in mice have shown that it can reduce some of the neural damage seen in Alzheimer's disease. The main psychoactive ingredient, tetrahydrocannabinol (THC), is approved by the Food and Drug Administration to treat anorexia in AIDS patients and the nausea triggered by chemotherapy. Although recreational drug users usually smoke marijuana, patients prescribed THC take it as capsules. Many people find the side effects hard to bear, however. The exact cause of these side effects is unclear. In the brain, THC binds to receptors called CB1 and CB2, which are involved in neural development as well as pain perception and appetite. The receptors are normally activated by similar compounds, called endocannabinoids, that are produced by the human body. When one of these compounds binds to CB1, it suppresses the activity of an enzyme called cyclooxygenase-2 (COX-2). The enzyme has many functions. For instance, painkillers such as ibuprofen and aspirin work by blocking COX-2. Researchers have hypothesized that the suppression of COX-2 could be the cause of THC's side effects, such as memory problems. © 2013 American Association for the Advancement of Science
By BENEDICT CAREY Grading college students on quizzes given at the beginning of every class, rather than on midterms or a final exam, increases both attendance and overall performance, scientists reported Wednesday. The findings — from an experiment in which 901 students in a popular introduction to psychology course at the University of Texas took their laptops to class and were quizzed online — demonstrate that the computers can act as an aid to teaching, not just a distraction. Moreover, the study is the latest to show how tests can be used to enhance learning as well as measure it. The report, appearing in the journal PLoS One, found that this “testing effect” was particularly strong in students from lower-income households. Psychologists have known for almost a century that altering the timing of tests can affect performance. In the past decade, they have shown that taking a test — say, writing down all you can remember from a studied prose passage — can deepen the memory of that passage better than further study. The new findings stand as a large-scale prototype for how such testing effects can be exploited in the digital era, experts said, though they cautioned that it was not yet clear how widely they could be applied. “This study is important because it introduces a new method to implement frequent quizzing with feedback in large classrooms, which can be difficult to do,” said Jeffrey D. Karpicke, a professor of psychology at Purdue, who was not involved in the study. He added, “This is the first large study to show that classroom quizzing can help reduce achievement gaps” due to socioeconomic background. © 2013 The New York Times Company
Keyword: Learning & Memory
Link ID: 18960 - Posted: 11.23.2013
By Helen Briggs BBC News A condition where people experience a mixing of the senses, such as tasting words, has been linked with autism. Research suggests synaesthesia is nearly three times as common in adults with autism spectrum disorder than in the general population. The two conditions may share common features such as unusual wiring of the brain, say UK scientists. The study helps understanding of how people with autism experience life, says the National Autistic Society. Synaesthesia is a condition where one sense automatically triggers another. Some people experience tastes when they read or hear words, some perceive numbers as shapes, others see colours when they hear music. People with synaesthesia might say: "The letter q is dark brown," or: "The word 'hello' tastes like coffee," for example. Following anecdotal evidence of links between synaesthesia and Asperger's syndrome, researchers at the Autism Research Centre at Cambridge University set out to test the idea. More than 200 study participants - 164 adults diagnosed with high-functioning autism or Asperger's syndrome, and 97 adults without autism - were asked to fill in questionnaires to measure synaesthesia and autism traits. The study found one in five adults with autism spectrum conditions - a range of related developmental disorders, including autism and Asperger's syndrome - had synaesthesia compared with about 7% of people with no signs of the disorders. Prof Simon Baron-Cohen, who led the research, told BBC News: "Synaesthesia involves a mixing of the senses and it's a very subjective private experience, so the only way we know it's happening is if you ask people to report on their experiences. BBC © 2013
Link ID: 18948 - Posted: 11.20.2013