Chapter 13. Memory, Learning, and Development
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By DOUGLAS QUENQUA Like Pavlov’s dogs, most organisms can learn to associate two events that usually occur together. Now, a team of researchers says they have identified a gene that enables such learning. The scientists, at the University of Tokyo, found that worms could learn to avoid unpleasant situations as long as a specific insulin receptor remained intact. Roundworms were exposed to different concentrations of salt; some received food during the initial exposure, others did not. Later, when exposed to various concentrations of salt again, the roundworms that had been fed during the first stage gravitated toward their initial salt concentrations, while those that had been starved avoided them. But the results changed when the researchers repeated the experiment using worms with a defect in a particular receptor for insulin, a protein crucial to metabolism. Those worms could not learn to avoid the salt concentrations associated with starvation. “We looked for different forms of the receptor and found that a new one, which we named DAF-2c, functions in taste-aversion learning,” said Masahiro Tomioka, a geneticist at the University of Tokyo and an author of the study, which was published in the journal Science. “It turned out that only this form of the receptor can support learning” in roundworms. While human insulin receptors bear some resemblance to those of a roundworm, more study is needed to determine if it plays a similar role in memory and decision-making, Dr. Tomioka said. But studies have suggested a link between insulin levels and Alzheimer’s disease in humans. © 2014 The New York Times Company
Sara Reardon Broad population studies are shedding light on the genetic causes of mental disorders. Researchers seeking to unpick the complex genetic basis of mental disorders such as schizophrenia have taken a huge step towards their goal. A paper1 published in Nature this week ties 108 genetic locations to schizophrenia — most for the first time. The encouraging results come on the same day as a US$650-million donation to expand research into psychiatric conditions. Philanthropist Ted Stanley gave the money to the Stanley Center for Psychiatric Research at the Broad Institute in Cambridge, Massachusetts. The institute describes the gift as the largest-ever donation for psychiatric research. “The assurance of a very long life of the centre allows us to take on ambitious long-term projects and intellectual risks,” says its director, Steven Hyman. The centre will use the money to fund genetic studies as well as investigations into the biological pathways involved in conditions such as schizophrenia, autism and bipolar disorder. The research effort will also seek better animal and cell models for mental disorders, and will investigate chemicals that might be developed into drugs. The Nature paper1 was produced by the Psychiatric Genomics Consortium (PGC) — a collaboration of more than 80 institutions, including the Broad Institute. Hundreds of researchers from the PGC pooled samples from more than 150,000 people, of whom 36,989 had been diagnosed with schizophrenia. This enormous sample size enabled them to spot 108 genetic locations, or loci, where the DNA sequence in people with schizophrenia tends to differ from the sequence in people without the disease. “This paper is in some ways proof that genomics can succeed,” Hyman says. © 2014 Nature Publishing Group
Most of the genetic risk for autism comes from versions of genes that are common in the population rather than from rare variants or spontaneous glitches, researchers funded by the National Institutes of Health have found. Heritability also outweighed other risk factors in this largest study of its kind to date. About 52 percent of the risk for autism was traced to common and rare inherited variation, with spontaneous mutations contributing a modest 2.6 percent of the total risk. “Genetic variation likely accounts for roughly 60 percent of the liability for autism, with common variants comprising the bulk of its genetic architecture,” explained Joseph Buxbaum, Ph.D., of the Icahn School of Medicine at Mount Sinai (ISMMS), New York City. “Although each exerts just a tiny effect individually, these common variations in the genetic code add up to substantial impact, taken together.” Buxbaum, and colleagues of the Population-Based Autism Genetics and Environment Study (PAGES) Consortium, report on their findings in a unique Swedish sample in the journal Nature Genetics, July 20, 2014. “Thanks to the boost in statistical power that comes with ample sample size, autism geneticists can now detect common as well as rare genetic variation associated with risk,” said Thomas R. Insel, M.D., director of the NIH’s National Institute of Mental Health (NIMH). “Knowing the nature of the genetic risk will reveal clues to the molecular roots of the disorder. Common variation may be more important than we thought.”
By HENRY L. ROEDIGER III TESTS have a bad reputation in education circles these days: They take time, the critics say, put students under pressure and, in the case of standardized testing, crowd out other educational priorities. But the truth is that, used properly, testing as part of an educational routine provides an important tool not just to measure learning, but to promote it. In one study I published with Jeffrey D. Karpicke, a psychologist at Purdue, we assessed how well students remembered material they had read. After an initial reading, students were tested on some passages by being given a blank sheet of paper and asked to recall as much as possible. They recalled about 70 percent of the ideas. Other passages were not tested but were reread, and thus 100 percent of the ideas were re-exposed. In final tests given either two days or a week later, the passages that had been tested just after reading were remembered much better than those that had been reread. What’s at work here? When students are tested, they are required to retrieve knowledge from memory. Much educational activity, such as lectures and textbook readings, is aimed at helping students acquire and store knowledge. Various kinds of testing, though, when used appropriately, encourage students to practice the valuable skill of retrieving and using knowledge. The fact of improved retention after a quiz — called the testing effect or the retrieval practice effect — makes the learning stronger and embeds it more securely in memory. This is vital, because many studies reveal that much of what we learn is quickly forgotten. Thus a central challenge to learning is finding a way to stem forgetting. © 2014 The New York Times Company
Keyword: Learning & Memory
Link ID: 19861 - Posted: 07.21.2014
By Meeri Kim Babies start with simple vowel sounds — oohs and aahs. A mere months later, the cooing turns into babbling — “bababa” — showing off a newfound grasp of consonants. A new study has found that a key part of the brain involved in forming speech is firing away in babies as they listen to voices around them. This may represent a sort of mental rehearsal leading up to the true milestone that occurs after only a year of life: baby’s first words. Any parent knows how fast babies learn how to comprehend and use language. The skill develops so rapidly and seemingly without much effort, but how do they do it? Researchers at the University of Washington are a step closer to unraveling the mystery of how babies learn how to speak. They had a group of 7- and 11-month-old infants listen to a series of syllables while sitting in a brain scanner. Not only did the auditory areas of their brains light up as expected but so did a region crucial to forming higher-level speech, called Broca’s area. A year-old baby sits in a brain scanner, called magnetoencephalography -- a noninvasive approach to measuring brain activity. The baby listens to speech sounds like "da" and "ta" played over headphones while researchers record her brain responses. (Institute for Learning and Brain Sciences, University of Washington) These findings may suggest that even before babies utter their first words, they may be mentally exercising the pivotal parts of their brains in preparation. Study author and neuroscientist Patricia Kuhl says that her results reinforce the belief that talking and reading to babies from birth is beneficial for their language development, along with exaggerated speech and mouth movements (“Hiii cuuutie! How are youuuuu?”). © 1996-2014 The Washington Post
Tania Browne As a teenager, I lost my grandfather. But he wasn't dead. He still had his favourite music, he still loved to walk in the woods and name the flowers and plants, and he loved his soap operas. He was alive, but gone. A dignified man, a former aircraft engineer and oil company salesman, reduced to the status of a bewildered toddler lost in a shopping centre. When he died, our family felt an odd mix of relief, then guilt at the relief. The man we loved had left his body years before the body gave out. This was 30 years ago. But while a cure is still far away, two new techniques may at least be able to forewarn us of dementia, and allow us to plan treatment for ourselves or loved ones before any outward symptoms are apparent. According to Alzheimer's Research UK, my experience is currently shared by 24m relatives and close friends of the 800 000 diagnosed dementia sufferers in the UK. In December last year, a G8 summit was told by Alzheimer's Disease International that the worldwide figure was 44m and set to treble by 2050, as the life expectancy of people in middle and lower income countries soars – precisely the countries who have either depleted or non-existent healthcare systems. Dementia is a serious time bomb. “Dementia” covers about 100 conditions, all resulting from large scale brain cell death. People often think that when they're diagnosed they're in the early stages. Yet cell death can be occurring for 10-15 years or more before any outward symptoms occur, and by the time they're diagnosed many dementia patients have already lost one fifth of their memory cells. © 2014 Guardian News and Media Limited
Link ID: 19856 - Posted: 07.21.2014
Emily A. Holmes, Michelle G. Craske & Ann M. Graybiel How does one human talking to another, as occurs in psychological therapy, bring about changes in brain activity and cure or ease mental disorders? We don't really know. We need to. Mental-health conditions, such as post-traumatic stress disorder (PTSD), obsessive–compulsive disorder (OCD), eating disorders, schizophrenia and depression, affect one in four people worldwide. Depression is the third leading contributor to the global burden of disease, according to the World Health Organization. Psychological treatments have been subjected to hundreds of randomized clinical trials and hold the strongest evidence base for addressing many such conditions. These activities, techniques or strategies target behavioural, cognitive, social, emotional or environmental factors to improve mental or physical health or related functioning. Despite the time and effort involved, they are the treatment of choice for most people (see ‘Treating trauma with talk therapy’). For example, eating disorders were previously considered intractable within our life time. They can now be addressed with a specific form of cognitive behavioural therapy (CBT)1 that targets attitudes to body shape and disturbances in eating habits. For depression, CBT can be as effective as antidepressant medication and provide benefits that are longer lasting2. There is also evidence that interpersonal psychotherapy (IPT) is effective for treating depression. Ian was filling his car with petrol and was caught in the cross-fire of an armed robbery. His daughter was severely injured. For the following decade Ian suffered nightmares, intrusive memories, flashbacks of the trauma and was reluctant to drive — symptoms of post-traumatic stress disorder (PTSD). © 2014 Nature Publishing Group,
By Emily Anthes The women that come to see Deane Aikins, a clinical psychologist at Wayne State University, in Detroit, are searching for a way to leave their traumas behind them. Veterans in their late 20s and 30s, they served in Iraq and Afghanistan. Technically, they’d been in non-combat positions, but that didn’t eliminate the dangers of warfare. Mortars and rockets were an ever-present threat on their bases, and they learned to sleep lightly so as not to miss alarms signaling late-night attacks. Some of the women drove convoys of supplies across the desert. It was a job that involved worrying about whether a bump in the road was an improvised explosive device, or if civilians in their path were strategic human roadblocks. On top of all that, some of the women had been sexually assaulted by their military colleagues. After one woman was raped, she helped her drunk assailant sneak back into his barracks because she worried that if they were caught, she’d be disciplined or lose her job. These traumas followed the women home. Today, far from the battlefield, they find themselves struggling with vivid flashbacks and nightmares, tucking their guns under their pillows at night. Some have turned to alcohol to manage their symptoms; others have developed exhausting routines to avoid any people or places that might trigger painful memories and cause them to re-live their experiences in excruciating detail. © 2014 Nautilus,
Fearful memories can be dampened by imagining past traumas in a safe setting. The "extinction" of fear is fragile, however, and surprising or unexpected events can cause fear memories to return. Inactivating brain areas that detect novelty prevents relapse of unwanted fear memories. Traumatic and emotional experiences often lead to debilitating mental health disorders, including post-traumatic stress disorder (PTSD). In the clinic, it is typical to use behavioral therapies such as exposure therapy to help reduce fear in patients suffering from traumatic memories. Using these approaches, patients are asked to remember the circumstances and stimuli surrounding their traumatic memory in a safe setting in order to "extinguish" their fear response to those events. While effective in many cases, the loss of fear and anxiety achieved by these therapies is often short-lived—fear returns or relapses under a variety of conditions. Many years ago, the famous Russian physiologist Ivan Pavlov noted that simply exposing animals to novel or unexpected events could cause extinguished responses (such as salivary responses to sounds) to return. Might exposure to novelty also cause extinguished fear responses to return? In a recent study (Maren, 2014), rats first learned that an innocuous tone predicted an aversive (but mild) electric shock to their feet. The subsequent fear response to the tone was then extinguished by presenting the stimulus to the animals many times without the shock. After the fear response to the tone was reduced with the extinction procedure, they were then presented with the tone in either a new location (a novel test box) or in a familiar location, but in the presence of an unexpected sound (a noise burst). In both cases, fear to the tone returned as Pavlov predicted: the unexpected places and sounds led to a disinhibition of fear—in other words, fear relapsed. © 2014 Publiscize
Obese women may have a "food learning impairment" that could explain their attitude to food, research from Yale School of Medicine suggests. Tests on groups of obese and healthy-weight people found that the obese women performed worst when asked to remember a sequence of food picture cards. Writing in Current Biology, Yale researchers tested 135 men and women. The findings could lead to new ways to tackle obesity, the study says. Study author Ifat Levy, assistant professor at Yale School of Medicine, said the difference in the performance of the obese women compared with the other groups was "really striking" and "significant". The tests looked at an individual's ability to learn and predict the appearance of pictures of food or money on coloured cards. The participants were told they would be given whatever appeared on these "reward" cards. In the first phase, the reward cards always followed a particular coloured card in a sequence. Later, the order was changed and the reward cards appeared following a different coloured card. During this time, participants were asked to predict the likelihood of a reward card appearing as the cards were shown one by one. The results showed that obese women performed worst because they overestimated how often the pictures of food, including pretzels or chocolate, appeared. Even after researchers had accounted for other factors, there was still a large difference in their learning performance. Prof Levy said: "This is not a general learning impairment, as obese women had no problem learning when the reward was money rather than food. BBC © 2014
Kelly Servick If you’re a bird enthusiast, you can pick out the “chick-a-DEE-dee” song of the Carolina chickadee with just a little practice. But if you’re an environmental scientist faced with parsing thousands of hours of recordings of birdsongs in the lab, you might want to enlist some help from your computer. A new approach to automatic classification of birdsong borrows techniques from human voice recognition software to sort through the sounds of hundreds of species and decides on its own which features make each one unique. Collectors of animal sounds are facing a data deluge. Thanks to cheap digital recording devices that can capture sound for days in the field, “it’s really, really easy to collect sound, but it’s really difficult to analyze it,” say Aaron Rice, a bioacoustics researcher at Cornell University, who was not involved in the new work. His lab has collected 6 million hours of underwater recordings, from which they hope to pick out the signature sounds of various marine mammals. Knowing where and when a certain species is vocalizing might help scientists understand habitat preferences, track their movements or population changes, and recognize when a species is disrupted by human development. But to keep these detailed records, researchers rely on software that can reliably sort through the cacophony they capture in the field. Typically, scientists build one computer program to recognize one species, and then start all over for another species, Rice says. Training a computer to recognize lots of species in one pass is “a challenge that we’re all facing.” © 2014 American Association for the Advancement of Science.
Keyword: Learning & Memory
Link ID: 19849 - Posted: 07.19.2014
|By Nidhi Subbaraman and SFARI.org A team at Duke University in Durham, North Carolina, is set to launch a $40 million clinical trial to explore stem cells from umbilical cord blood as a treatment for autism. But experts caution that the trial is premature. A $15 million grant from the Marcus Foundation, a philanthropic funding organization based in Atlanta, will bankroll the first two years of the five-year trial, which also plans to test stem cell therapy for stroke and cerebral palsy. The autism arm of the trial aims to enroll 390 children and adults. Joanne Kurtzberg, the trial’s lead investigator, has extensive experience studying the effectiveness of cord blood transplants for treating various disorders, such as leukemia and sickle cell anemia. Most recently, she showed that cord blood transplants can improve the odds of survival for babies deprived of oxygen at birth. A randomized trial of the approach for this condition is underway. “To really sort out if [stem] cells can treat these children, we need to do randomized, controlled trials that are well designed and well controlled, and that’s what we intend to do,” says Kurtzberg, professor of pediatrics and pathology at Duke. “We firmly believe we should be moving ahead in the clinic.” Early animal studies have shown that stem cells isolated from umbilical cord blood can stimulate cells in the spinal cord to regrow their myelin layers, and in doing so help restore connections with surrounding cells. Autism is thought to result from impaired connectivity in the brain. Because of this, some groups of children with the disorder may benefit from a stem cell transplant, Kurtzberg says. © 2014 Scientific American
Associated Press The rate of Alzheimer's disease and other dementias is falling in the United States and some other rich countries - good news about an epidemic that is still growing simply because more people are living to an old age, new studies show. An American over age 60 today has a 44 percent lower chance of developing dementia than a similar-aged person did roughly 30 years ago, the longest study of these trends in the U.S. concluded. Dementia rates also are down in Germany, a study there found. "For an individual, the actual risk of dementia seems to have declined," probably because of more education and control of health factors such as cholesterol and blood pressure, said Dr. Kenneth Langa. He is a University of Michigan expert on aging who discussed the studies Tuesday at the Alzheimer's Association International Conference in Copenhagen. The opposite is occurring in some poor countries that have lagged on education and health, where dementia seems to be rising. More than 5.4 million Americans and 35 million people worldwide have Alzheimer's, the most common form of dementia. It has no cure, and current drugs only temporarily ease symptoms. A drop in rates is a silver lining in the so-called silver tsunami - the expected wave of age-related health problems from an older population. Alzheimer's will remain a major public health issue, but countries where rates are dropping may be able to lower current projections for spending and needed services, experts said. © 2014 Hearst Communications, Inc.
Link ID: 19838 - Posted: 07.16.2014
By PAULA SPAN What we really want, if we’re honest, is a pill or a shot that would allow us to stop worrying about ever sinking into dementia. Instead, what we’re hearing about preventing dementia is, in many ways, the same stuff we hear about preventing other kinds of illnesses. Healthy lifestyles. Behavioral modification. Stress reduction. At the Alzheimer’s Association International Conference in Copenhagen this week, researchers from Montefiore Medical Center and the Albert Einstein College of Medicine were among the scientists presenting findings that had little to do with amyloid in the brain and a lot to do with how people feel and act and cope with life. “A number of people have been interested in modifiable lifestyle factors for years,” said Richard Lipton, a neurologist at the college and director of the Einstein Aging Study, which has tracked cognition in elderly Bronx residents since the 1980s. But interest has increased lately, he said: “It’s at least in part a reflection of disappointing drug trials.” Medications have failed, over and over, to prevent or cure or substantially slow the ravages of dementing diseases. What else might help? Dr. Lipton and his colleagues, who monitor about 600 people aged 70 to 105, have been exploring the impact of stress. More specifically, they have been measuring “perceived stress,” a metric not so much about unpleasant things happening as how people respond to them. They use a scale based on the answers to 13 questions like, “In the past month, how often have you felt confident about your ability to handle your personal problems?” and “In the past month, how often have you felt difficulties were piling up so high you could not overcome them?” © 2014 The New York Times Company
Link ID: 19837 - Posted: 07.16.2014
By BENEDICT CAREY The 8-year-old juggling a soccer ball and the 48-year-old jogging by, with Japanese lessons ringing from her earbuds, have something fundamental in common: At some level, both are wondering whether their investment of time and effort is worth it. How good can I get? How much time will it take? Is it possible I’m a natural at this (for once)? What’s the percentage in this, exactly? Scientists have long argued over the relative contributions of practice and native talent to the development of elite performance. This debate swings back and forth every century, it seems, but a paper in the current issue of the journal Psychological Science illustrates where the discussion now stands and hints — more tantalizingly, for people who just want to do their best — at where the research will go next. The value-of-practice debate has reached a stalemate. In a landmark 1993 study of musicians, a research team led by K. Anders Ericsson, a psychologist now at Florida State University, found that practice time explained almost all the difference (about 80 percent) between elite performers and committed amateurs. The finding rippled quickly through the popular culture, perhaps most visibly as the apparent inspiration for the “10,000-hour rule” in Malcolm Gladwell’s best-selling “Outliers” — a rough average of the amount of practice time required for expert performance. Scientists begin to shed light on the placenta, an important organ that we rarely think of; virtual reality companies work out the kinks in their immersive worlds; research shows that practice may not be as important as once thought. The new paper, the most comprehensive review of relevant research to date, comes to a different conclusion. Compiling results from 88 studies across a wide range of skills, it estimates that practice time explains about 20 percent to 25 percent of the difference in performance in music, sports and games like chess. In academics, the number is much lower — 4 percent — in part because it’s hard to assess the effect of previous knowledge, the authors wrote. © 2014 The New York Times Company
Keyword: Learning & Memory
Link ID: 19835 - Posted: 07.15.2014
By Gary Stix Popular neuroscience books have made much in recent years of the possibility that the adult brain is capable of restoring lost function or even enhancing cognition through sustained mental or physical activities. One piece of evidence often cited is a 14-year-old study that that shows that London taxi drivers have enlarged hippocampi, brain areas that store a mental map of one’s surroundings. Taxi drivers, it is assumed, have better spatial memory because they must constantly distinguish the streets and landmarks of Shepherd’s Bush from those of Brixton. A mini-industry now peddles books with titles like The Brain that Changes Itself or Rewire Your Brain: Think Your Way to a Better Life. Along with self-help guides, the value of games intended to enhance what is known as neuroplasticity are still a topic of heated debate because no one knows for sure whether or not they improve intelligence, memory, reaction times or any other facet of cognition. Beyond the controversy, however, scientists have taken a number of steps in recent years to start to answer the basic biological questions that may ultimately lead to a deeper understanding of neuroplasticity. This type of research does not look at whether psychological tests used to assess cognitive deficits can be refashioned with cartoonlike graphics and marketed as games intended to improve mental skills. Rather, these studies attempt to provide a simple definition of how mutable the brain really is at all life stages, from infancy onward into adulthood. One ongoing question that preoccupies the basic scientists pursuing this line of research is how routine everyday activities—sleep, wakefulness, even any sort of movement—may affect the ability to perceive things in the surrounding environment. One of the leaders in these efforts is Michael Stryker, who researches neuroplasticity at the University of California San Francisco. Stryker headed a group that in 2010 published a study on what happened when mice run on top of a Styrofoam ball floating on air. They found that neurons in a brain region that processes visual signals—the visual cortex—nearly doubled their firing rate when the mice ran on the ball. © 2014 Scientific American
By ALEX STONE Last summer, in a failed attempt at humor, Clorox ran an online ad that declared, “Like dogs or other house pets, new dads are filled with good intentions but lacking the judgment and fine motor skills to execute well.” Although the company pulled the ad amid a flurry of scorn from the online commentariat, it nevertheless played to a remarkably widespread stereotype — that fathers are somehow unfit to raise children. In “Do Fathers Matter?” — spoiler alert: they do — the veteran science writer Paul Raeburn jumps to Dad’s defense, drawing on several decades of research and his own experience as a five-time father. What emerges is a thought-provoking field piece on the science of fatherhood, studded with insights on how to apply it in the real world. Historically, developmental psychologists have largely dismissed fathers as irrelevant. Nearly half the articles on child and adolescent psychology published in leading journals from 1997 to 2005, for example, make no mention of fathers; before 1970, when fathers weren’t even allowed in delivery rooms, less than a fifth of the research on parental bonding took them into account. This bias reflects a deeply ingrained assumption that fathers play a marginal role in how their children turn out, a belief enshrined in the theory of infant attachment, which grew out of the work of the British psychiatrist John Bowlby in the second half of the 20th century. “It focused exclusively on mothers,” Mr. Raeburn writes. “The role of the father, Bowlby believed, was to provide support for the mother. In the drama of childhood, he was merely a supporting actor.” This was more or less the established view until a few decades ago, when psychologists, motivated in part by the growing number of women entering the work force, finally started paying attention to fathers. © 2014 The New York Times Company
|By Maria Burke and ChemistryWorld The world needs to tackle head-on the market failures undermining dementia research and drug development, UK Prime Minister David Cameron told a summit of world health and finance leaders in London in June. He announced an investigation into how to get medicines to patients earlier, extend patents and facilitate research collaborations, to report this autumn. But just how much difference will these sorts of measures make when scientists are still grappling with exactly what causes different types of dementia? Added to these problems is that dementia has become a graveyard for a large number of promising drugs. A recent study looked at how 244 compounds in 413 clinical trials fared for Alzheimer's disease between 2002 and 2012. The researchers findings paint a gloomy picture. Of those 244 compounds, only one was approved. The researchers report that this gives Alzheimer's disease drug candidates one of the highest failures rates of any disease area – 99.6%, compared with 81% for cancer. ‘Dementia is a ticking bomb costing the global economy £350 billion and yet progress with research is achingly slow,’ warned the World Dementia Envoy, Dennis Gillings. Businesses need incentives to invest in research and bring in faster, cheaper clinical trials, or the world won’t meet the ambition to find a cure or disease-modifying therapy by 2025, he added. ‘We need to free up regulation so that we can test ground-breaking new drugs, and examine whether the period for market exclusivity could be extended.’ © 2014 Scientific American
Link ID: 19828 - Posted: 07.15.2014
By Fredrick Kunkle Sleep disturbances such as apnea may increase the risk of Alzheimer’s disease, while moderate exercise in middle age and mentally stimulating games, such as crossword puzzles, may prevent the onset of the dementia-causing disease, according to new research to be presented Monday. The findings — which are to be introduced during the six-day Alzheimer’s Association International Conference in Copenhagen — bolster previous studies that suggest sleep plays a critical role in the aging brain’s health, perhaps by allowing the body to cleanse itself of Alzheimer's-related compounds during down time. The studies also add to a growing body of literature that suggests keeping the brain busy keeps it healthy. The battle against Alzheimer’s disease has become more urgent for the United States and other developing nations as their populations turn increasingly gray. The disease is the leading cause of dementia in older people and afflicts more than 5 million Americans. At its current pace, the number is expected to soar to 16 million people by 2050. In 2012, the United States adopted a national plan to combat the disease and the G-8 nations last year adopted a goal of providing better treatment and prevention by 2025. Erin Heintz, a spokeswoman for the Alzheimer’s Association, said U.S. government funding to combat the disease now stands at about $500 million a year. To reach its 2025 goal, the United States should be spending $2 billion a year, she said.
One in three cases of Alzheimer's disease worldwide is preventable, according to research from the University of Cambridge. The main risk factors for the disease are a lack of exercise, smoking, depression and poor education, it says. Previous research from 2011 put the estimate at one in two cases, but this new study takes into account overlapping risk factors. Alzheimer's Research UK said age was still the biggest risk factor. Writing in The Lancet Neurology, the Cambridge team analysed population-based data to work out the main seven risk factors for Alzheimer's disease. These are: Diabetes Mid-life hypertension Mid-life obesity Physical inactivity Depression Smoking Low educational attainment They worked out that a third of Alzheimer's cases could be linked to lifestyle factors that could be modified, such as lack of exercise and smoking. The researchers then looked at how reducing these factors could affect the number of future Alzheimer's cases. They found that by reducing each risk factor by 10%, nearly nine million cases of the disease could be prevented by 2050. In the UK, a 10% reduction in risk factors would reduce cases by 8.8%, or 200,000, by 2050, they calculated. BBC © 2014
Link ID: 19824 - Posted: 07.14.2014