Chapter 13. Memory, Learning, and Development

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By Marian Vidal-Fernandez, Ana Nuevo-Chiquero, The title of this article might trigger self-satisfied smiles among first-borns, and some concerns among the rest of us. Many studies show children born earlier in the family enjoy better wages and more education, but until now we didn’t really know why. Our recently published findings are the first to suggest advantages of first born siblings start very early in life—around zero to three years old! We observe parents changing their behaviour as new children are born, and offering less cognitive stimulation to children of higher birth order. It now seems clear that for those born and raised in high-income countries such as the United States, the UK and Norway, earlier-born children enjoy higher wages and education as adults—known as the “birth order effect”. Comparing two siblings, the greater the difference in their birth order, the greater the relative benefit to the older child. However, to date we’ve had no evidence that explains where such differences come from. We know it’s not an effect of family size, because the effect remains when comparing siblings within the same family and families with the same number of children. While it makes sense that parents earn more money and gain experience as they get older and have more children, they also need to divide their economic resources and attention among any children that arrive after the first born. We wondered where in childhood these differences began, and what the cause or causes might be. © 2016 Scientific American,

Keyword: Development of the Brain; Learning & Memory
Link ID: 22835 - Posted: 11.05.2016

Laura Sanders A protein that can switch shapes and accumulate inside brain cells helps fruit flies form and retrieve memories, a new study finds. Such shape-shifting is the hallmark move of prions — proteins that can alternate between two forms and aggregate under certain conditions. In fruit flies’ brain cells, clumps of the prionlike protein called Orb2 stores long-lasting memories, report scientists from the Stowers Institute for Medical Research in Kansas City, Mo. Figuring out how the brain forms and calls up memories may ultimately help scientists devise ways to restore that process in people with diseases such as Alzheimer’s. The new finding, described online November 3 in Current Biology, is “absolutely superb,” says neuroscientist Eric Kandel of Columbia University. “It fills in a lot of missing pieces.” People possess a version of the Orb2 protein called CPEB, a commonality that suggests memory might work in a similar way in people, Kandel says. It’s not yet known whether people rely on the prion to store long-term memories. “We can’t be sure, but it’s very suggestive,” Kandel says. When neuroscientist Kausik Si and colleagues used a genetic trick to inactivate Orb2 protein, male flies were worse at remembering rejection. These lovesick males continued to woo a nonreceptive female long past when they should have learned that courtship was futile. In different tests, these flies also had trouble remembering that a certain odor was tied to food. |© Society for Science & the Public 2000 - 2016. All rights reserved.

Keyword: Learning & Memory; Prions
Link ID: 22833 - Posted: 11.04.2016

By Simon Makin Cerebral autopsy specimen of a patient diagosed having Alzheimer Disease. In the HE stain numerous plaque formations within the neuropil background are visible. Credit: WIKIPEDIA, CC BY-SA 3.0 On Monday Pres. Barack Obama proclaimed November “National Alzheimer's Disease Awareness Month.” The administration’s ambitious goal is to prevent and treat Alzheimer's by 2025. Although there are currently no approved therapies that slow or stop progression of the disease, several approaches are showing promise. In a study published today in Science Translational Medicine, a team from Merck Research Laboratories reports results of early human and animal trials of a drug called verubecestat, which targets the production of protein plaques associated with the disease. “It's a summary of the discovery and early-stage profiling of what we hope is going to be a new therapeutic for Alzheimer's,” says team leader Matthew Kennedy. “It represents well over a decade of investment in this project by many, many scientists.” Definitive conclusions will have to await the results of larger, ongoing phase III clinical trials to assess their efficacy, effectiveness and safety, but the results are promising, experts say. Verubecestat is a so-called BACE1 inhibitor. BACE1 (for Beta-site Amyloid precursor protein Cleaving Enzyme 1, aka beta-secretase 1) is an enzyme involved in producing amyloid beta (Ab), a protein that clumps together, eventually forming the plaques surrounding neurons that are the disease's key hallmark. The amyloid hypothesis of Alzheimer's proposes that the accumulation of amyloid beta aggregates in the brain drives a cascade of biological events leading to neurodegeneration. By blocking BACE1, the hope is this approach could prevent the buildup of these clumps in the first place. But until now, development of these drugs has been hindered by problems finding molecules with the right characteristics, and concerns over theoretical and actual side effects. © 2016 Scientific American

Keyword: Alzheimers
Link ID: 22827 - Posted: 11.03.2016

By Virginia Morell Human hunters may be making birds smarter by inadvertently shooting those with smaller brains. That’s the conclusion of a new study, which finds that hunting may be exerting a powerful evolutionary force on bird populations in Denmark, and likely wherever birds are hunted. But the work also raises a red flag for some researchers who question whether the evolution of brain size can ever be tied to a single factor. The new work “broadens an emerging view that smarts really do matter in the natural, and increasingly human-dominated, world,” says John Marzluff, a wildlife biologist and expert on crow cognition at the University of Washington in Seattle who was not involved with the work. Hunting and fishing are known to affect many animal populations. For instance, the pike-perch in the Finnish Archipelago Sea has become smaller over time thanks to fishing, which typically removes the largest individuals from a population. This pressure also causes fish to reach sexual maturity earlier. On land, natural predators like arctic foxes and polar bears can also drive their prey species to become smarter because predators are most likely to catch those with smaller brains. For instance, a recent study showed that common eiders (maritime ducks) that raise the most chicks also have the largest heads and are better at forming protective neighborhood alliances than ducks with smaller heads—and presumably, brains. © 2016 American Association for the Advancement of Science

Keyword: Learning & Memory; Evolution
Link ID: 22820 - Posted: 11.02.2016

Bruce Bower Many preschoolers take a surprisingly long and bumpy mental path to the realization that people can have mistaken beliefs — say, thinking that a ball is in a basket when it has secretly been moved to a toy box. Traditional learning curves, in which kids gradually move from knowing nothing to complete understanding, don’t apply to this landmark social achievement and probably to many other types of learning, a new study concludes. Kids ranging in age from 3 to 5 often go back and forth between passing and failing false-belief tests for several months to more than one year, say psychologist Sara Baker of the University of Cambridge and her colleagues. A small minority of youngsters jump quickly from always failing to always passing these tests, the scientists report October 20 in Cognitive Psychology. “If these results are replicated, it will surprise a lot of researchers that there is such a low level of sudden insight into false beliefs,” says psychologist Malinda Carpenter, currently at the Max Planck Institute for Evolutionary Anthropology in Leipzig. Early childhood researchers generally assume that preschoolers either pass or fail false-belief tests, with a brief transition between the two, explains Carpenter, who did not participate in the new study. Grasping that others sometimes have mistaken beliefs is a key step in social thinking. False-belief understanding may start out as something that can be indicated nonverbally but not described. Human 2-year-olds and even chimpanzees tend to look toward spots where a person would expect to find a hidden item that only the children or apes have seen moved elsewhere (SN Online: 10/6/16). © Society for Science & the Public 2000 - 2016

Keyword: Learning & Memory; Development of the Brain
Link ID: 22816 - Posted: 11.01.2016

By Jesse Singal For a long time, the United States’ justice system has been notorious for its proclivity for imprisoning children. Because of laws that grant prosecutors and judges discretion to bump juveniles up to the category of “adult” when they commit crimes deemed serious enough by the authorities, the U.S. is an outlier in locking up kids, with some youthful defendants even getting life sentences. Naturally, this has attracted a great deal of outrage and advocacy from human-rights organizations, who argue that kids, by virtue of not lacking certain judgment, foresight, and decision-making abilities, should be treated a bit more leniently. Writing for the Marshall Project and drawing on some interesting brain science, Dana Goldstein takes the argument about youth incarceration even further: We should also rethink our treatment of offenders who are young adults. As Goldstein explains, the more researchers study the brain, the more they realize that it takes decades for the organ to develop fully and to impart to its owners their full, adult capacities for reasoning. “Altogether,” she writes, “the research suggests that brain maturation continues into one’s twenties and even thirties.” Many of these insights come from the newest generation of neuroscience research. “Everyone has always known that there are behavioral changes throughout the lifespan,” Catherine Lebel, an assistant professor of radiology at the University of Calgary who has conducted research into brain development, told Goldstein. “It’s only with new imaging techniques over the last 15 years that we’ve been able to get at some of these more subtle changes.” ! © 2016, New York Media LLC.

Keyword: Attention; Development of the Brain
Link ID: 22813 - Posted: 11.01.2016

Emily Sohn After a mother killed her four young children and then herself last month in rural China, onlookers quickly pointed to life circumstances. The family lived in extreme poverty, and bloggers speculated that her inability to escape adversity pushed her over the edge. Can poverty really cause mental illness? It's a complex question that is fairly new to science. Despite high rates of both poverty and mental disorders around the world, researchers only started probing the possible links about 25 years ago. Since then, evidence has piled up to make the case that, at the very least, there is a connection. People who live in poverty appear to be at higher risk for mental illnesses. They also report lower levels of happiness. That seems to be true all over the globe. In a 2010 review of 115 studies that spanned 33 countries across the developed and developing worlds, nearly 80 percent of the studies showed that poverty comes with higher rates of mental illness. Among people living in poverty, those studies also found, mental illnesses were more severe, lasted longer and had worse outcomes. And there's growing evidence that levels of depression are higher in poorer countries than in wealthier ones. Those kinds of findings challenge a long-held myth of the "poor but happy African sitting under a palm tree," says Johannes Haushofer, an economist and neurobiologist who studies interactions between poverty and mental health at Princeton University. © 2016 npr

Keyword: Schizophrenia; Depression
Link ID: 22811 - Posted: 10.31.2016

By Ruth Williams .Newly made cells in the brains of mice adopt a more complex morphology and connectivity when the animals encounter an unusual environment than if their experiences are run-of-the-mill. Researchers have now figured out just how that happens. According to a study published today (October 27) in Science, a particular type of cell—called an interneuron—in the hippocampus processes the animals’ experiences and subsequently shapes the newly formed neurons. “We knew that experience shapes the maturation of these new neurons, but what this paper does is it lays out the entire circuit through which that happens,” said Heather Cameron, a neuroscientist at the National Institute of Mental Health in Bethesda who was not involved with the work. “It’s a really nicely done piece of work because they go step-by-step and show all of the cells that are involved and how they’re connected.” Most of the cells in the adult mammalian brain are mature and don’t divide, but in a few regions, including an area of the hippocampus called the dentate gyrus, neurogenesis occurs. The dentate gyrus is thought to be involved in the formation of new memories. In mice, for instance, exploring novel surroundings electrically activates the dentate gyrus and can affect the production, maturation, and survival of the newly born cells. Now, Alejandro Schinder and his team at the Leloir Institute in Buenos Aires, Argentina, have investigated the process in detail. © 1986-2016 The Scientist

Keyword: Neurogenesis; Learning & Memory
Link ID: 22804 - Posted: 10.29.2016

By Catherine Caruso Babies and children undergo massive brain restructuring as they mature, and for good reason—they have a whole world of information to absorb during their sprint toward adulthood. This mental renovation doesn’t stop there, however. Adult brains continue to produce new cells and restructure themselves throughout life, and a new study in mice reveals more about the details of this process and the important role environmental experience plays. Through a series of experiments, researchers at the Leloir Institute in Buenos Aires showed that when adult mice are exposed to stimulating environments, their brains are able to more quickly integrate new brain cells into existing neural networks through a process that involves new and old cells connecting to one another via special helper cells called interneurons. The adult mammalian brain, long believed to lack the capacity to make new cells, has two main areas that continuously produce new neurons throughout life. One of these areas, the hippocampus (which is involved in memory, navigation, mood regulation and stress response) produces new neurons in a specialized region called the dentate gyrus. Many previous studies have focused on how the dentate gyrus produces new neurons and what happens to these neurons as they mature, but Alejandro Schinder and his colleagues at Leloir wanted to go one step further and understand how new neurons produced by the dentate gyrus are incorporated into the existing neural networks of the brain, and whether environment affects this process. © 2016 Scientific American

Keyword: Learning & Memory; Development of the Brain
Link ID: 22802 - Posted: 10.28.2016

By NICHOLAS BAKALAR Extremely high or low resting heart rates in young men may predict psychiatric illness later in life, a large new study has found. Researchers used heart rate and blood pressure data gathered at Swedish military inductions from 1969 to 2010, and linked them with information from the country’s detailed health records through the end of 2013. The study, in JAMA Psychiatry, included 1,794,361 men whose average age was 18 at induction. The highest heart rates — above 82 beats a minute — were associated with increased risks of obsessive-compulsive disorder, anxiety disorder and schizophrenia. The lowest, below 62 beats, were associated with an increased risk of substance abuse and violent criminality. Extremes in blood pressure followed similar patterns, but the associations were not as strong. The lead author, Antti Latvala, a researcher at the University of Helsinki, said that the reasons for the association remain unknown. But, he added, “These measures are indicators of slightly different reactivity to stimuli. These people might have elevated heart rates because of an elevated stress level that is then predictive of these disorders.” Still, Dr. Latvala said, a high or low heart rate does not mean future psychiatric disease. “These are very complex illnesses,” he said. “People with high or low heart rate have nothing to worry about because of these findings. This is just a tiny piece of the puzzle.” © 2016 The New York Times Company

Keyword: OCD - Obsessive Compulsive Disorder; Schizophrenia
Link ID: 22792 - Posted: 10.27.2016

Heidi Ledford Teaching parents of children with autism how to interact more effectively with their offspring brings the children benefits that linger for years, according to the largest and longest-running study of autism interventions. The training targeted parents with 2–4-year-old children with autism. Six years after the adults completed the year-long course, their children showed better social communication and reduced repetitive behaviours, and fewer were considered to have “severe” autism as compared to a control group, according to results published on 25 October in The Lancet1. “This is not a cure,” says child psychiatrist Jonathan Green of the University of Manchester, and an investigator on the study. “But it does have a sustained and substantial reduction in severity and that’s important in families.” John Constantino, a child psychiatrist at Washington University in St. Louis, Missouri, says that the results are “monumentally important”, because there has been little evidence showing that interventions for autism at an early stage are effective — even though researchers already broadly endorse the idea. "It is a rare long-term randomized controlled trial in a field in which there exists almost no data of this kind," he says. But he adds that the magnitude of the improvement was a disappointment, and that there were signs that the effects of treatment were diminishing over time. And although the therapy benefited communication skills and decreased repetitive behaviours, it did not lessen childrens' anxiety — another key symptom of autism. “Perhaps most of all, this underscores how desperately important it is that we develop higher-impact interventions,” he says. © 2016 Macmillan Publishers Limited,

Keyword: Autism; Learning & Memory
Link ID: 22791 - Posted: 10.26.2016

By Steven C. Pan A good night’s sleep can be transformative. Among its benefits are improved energy and mood, better immune system functioning and blood sugar regulation, and greater alertness and ability to concentrate. Given all of these benefits, the fact that a third of the human lifespan is spent sleeping makes evolutionary sense. However, sleep appears to have another important function: helping us learn. Across a plethora of memory tasks—involving word lists, maze locations, auditory tones, and more—going to sleep after training yields better performance than remaining awake. This has prompted many sleep researchers to reach a provocative conclusion: beyond merely supporting learning, sleep is vital, and perhaps even directly responsible, for learning itself. Recent discoveries from neuroscience provide insights into that possibility. Sleep appears to be important for long-term potentiation, a strengthening of signals between neurons that is widely regarded as a mechanism of learning and memory. Certain memories acquired during the day appear to be reactivated and “replayed” in the brain during sleep, which may help make them longer lasting. In some instances the amount of improvement that occurs on memory tasks positively correlates with the length of time spent in certain stages of sleep. These and other findings are generating great excitement among sleep researchers, as well as prompting heated debates about the degree to which sleep may or may not be involved in learning. To date, most sleep and learning research has focused on recall, which is the capacity to remember information. However, new research by Stéphanie Mazza and colleagues at the University of Lyon, recently published in the journal Psychological Science,suggests another potential benefit of sleep: improved relearning. © 2016 Scientific American

Keyword: Sleep; Learning & Memory
Link ID: 22787 - Posted: 10.26.2016

Merrit Kennedy Parents can reduce the risk of sudden infant death syndrome by keeping their child's crib in the same room, close to their bed, according to the American Academy of Pediatrics. That's one of the key recommendations in new guidance released today aimed at preventing SIDS, which claims the lives of approximately 3,500 infants every year in the United States. That number "initially decreased in the 1990s after a national safe sleep campaign, but has plateaued in recent years," the AAP adds. The pediatricians say that children should sleep in the same room but on a separate surface from their parents for at least the first six months of their lives, and ideally the first year. They say that this can halve the risk of SIDS. It also "removes the possibility of suffocation, strangulation, and entrapment that may occur when the infant is sleeping in an adult bed," according to the recommendations. The AAP discourages sharing a bed with an infant. You can read the AAP's full guidance here. These are a few more of the pediatricians' recommendations: Infants under a year old should always sleep lying on their backs. Side sleeping "is not safe and is not advised," the AAP says. Infants should always sleep on a firm surface covered by only a flat sheet. That's because soft mattresses "could create a pocket ... and increase the chance of rebreathing or suffocation if the infant is placed in or rolls over to the prone position." Smoking — both during pregnancy and around the infant after birth — can increase the risk of SIDS. Alcohol and illicit drugs during pregnancy can also contribute to SIDS, and "parental alcohol and/or illicit drug use in combination with bed-sharing places the infant at particularly high risk of SIDS," the pediatricians say. © 2016 npr

Keyword: Sleep; Development of the Brain
Link ID: 22786 - Posted: 10.25.2016

Bret Stetka Every day in the United States, millions of expectant mothers take a prenatal vitamin on the advice of their doctor. The counsel typically comes with physical health in mind: folic acid to help avoid fetal spinal cord problems; iodine to spur healthy brain development; calcium to be bound like molecular Legos into diminutive baby bones. But what about a child's future mental health? Questions about whether ADHD might arise a few years down the road or whether schizophrenia could crop up in young adulthood tend to be overshadowed by more immediate parental anxieties. As a friend with a newborn daughter recently fretted over lunch, "I'm just trying not to drop her!" Yet much as pediatricians administer childhood vaccines to guard against future infections, some psychiatrists now are thinking about how to shift their treatment-centric discipline toward one that also deals in early prevention. In 2013, University of Colorado psychiatrist Robert Freedman and colleagues recruited 100 healthy, pregnant women from greater Denver to study whether giving the B vitamin choline during pregnancy would enhance brain growth in the developing fetus. The moms-to-be were randomly given either a placebo or a form of choline called phosphatidylcholine. Choline itself is broken down by bacteria in the gut; by giving it in this related form the supplement can more effectively be absorbed into the bloodstream. © 2016 npr

Keyword: Schizophrenia; Development of the Brain
Link ID: 22777 - Posted: 10.22.2016

By Agata Blaszczak-Boxe Some rodents have a sweet tooth. And sometimes, you need to get crafty to reach your sugar fix. Rats have been filmed for the first time using hooked tools to get chocolate cereal – a manifestation of their critter intelligence. Akane Nagano and Kenjiro Aoyama, of Doshisha University in Kyotanabe, Japan, placed eight brown rats in a transparent box and trained them to pull small hooked tools to obtain the cereal that was otherwise beyond their reach. In one experiment they gave them two similar hooked tools, one of which worked well for the food retrieval task, and the other did not. The rats quickly learned to choose the correct tool for the job, selecting it 95 per cent of the time. The experiments showed that the rats understood the spatial arrangement between the food and the tool. The team’s study is the first to demonstrate that rats are able to use tools, says Nagano. The rats did get a little confused in the final experiment. When the team gave them a rake that looked the part but with a bottom was too soft and flimsy to move the cereal, they still tried to use it as much as the working tool that was also available. But, says Nagano, it is possible their eyesight was simply not good enough for them to tell that the flimsy tool wasn’t up to the task. The rodents’ crafty feat places them in the ever-growing club of known tool-using animals such as chimps, bearded capuchin monkeys, New Caledonian crows, alligators and even some fish. © Copyright Reed Business Information Ltd.

Keyword: Learning & Memory; Intelligence
Link ID: 22774 - Posted: 10.22.2016

Tina Hesman Saey VANCOUVER — Zika virus’s tricks for interfering with human brain cell development may also be the virus’s undoing. Zika infection interferes with DNA replication and repair machinery and also prevents production of some proteins needed for proper brain growth, geneticist Feiran Zhang of Emory University in Atlanta reported October 19 at the annual meeting of the American Society of Human Genetics. Levels of a protein called p53, which helps control cell growth and death, shot up by 80 percent in human brain cells infected with the Asian Zika virus strain responsible for the Zika epidemic in the Americas, Zhang said. The lab dish results are also reported in the Oct. 14 Nucleic Acids Research. Increased levels of the protein stop developing brain cells from growing and may cause the cells to commit suicide. A drug that inactivates p53 stopped brain cells from dying, Zhang said. Such p53 inhibitors could help protect developing brains in babies infected with Zika. But researchers would need to be careful giving such drugs because too little p53 can lead to cancer. Zika also makes small RNA molecules that interfere with production of proteins needed for DNA replication, cell growth and brain development, Zhang said. In particular, a small viral RNA called vsRNA-21 reduced the amount of microcephalin 1 protein made in human brain cells in lab dishes. The researchers confirmed the results in mouse experiments. That protein is needed for brain growth; not enough leads to the small heads seen in babies with microcephaly. Inhibitors of the viral RNAs might also be used in therapies, Zhang suggested. |© Society for Science & the Public 2000 - 2016

Keyword: Development of the Brain
Link ID: 22770 - Posted: 10.20.2016

By MARC SANTORA The morning after Christine Grounds gave birth to her son Nicholas, she awoke to find a neurologist examining her baby. It was summer 2006, and Nicholas was her first child. There had been no indication that anything was wrong during her pregnancy, but it was soon clear that there was a problem. “Did you know he has microcephaly?” she remembers the doctor asking matter-of-factly. Confused, she replied, “What is microcephaly?” This was before the Zika virus had spread from Brazil across South and Central America and the Caribbean and reached Florida. It was before doctors had determined that the virus could cause microcephaly, a birth defect in which children have malformed heads and severely stunted brain development. And it was before people had seen the devastating pictures of scores of newborns with the condition in Brazil and elsewhere that shocked the world this year. Ms. Grounds, a 45-year-old psychotherapist, and her husband, Jon Mir, who live in Manhattan, had no idea what microcephaly would mean for them or for their child. “We had a diagnosis but no prognosis,” recalled Mr. Mir, 44, who works in finance. The doctors could offer few answers. “We don’t know if he will walk,” the couple recalled being told. “We don’t know if he will talk. He might be in a vegetative state.” But the truth was, even the doctors did not know. As mosquito season draws to a close in much of the country, taking with it the major risk of new Zika infections, there are still more than 2,600 pregnant women who have tested positive for the virus in the United States and its territories, according to the Centers for Disease Control and Prevention. They, and thousands more around the world, face the prospect of giving birth to a child with microcephaly. © 2016 The New York Times Company

Keyword: Development of the Brain
Link ID: 22766 - Posted: 10.19.2016

By Gary Stix The new mantra for researchers fighting Alzheimer’s disease is “go early,” before memory loss or other pathology appears. The rationale for this approach holds that by the time dementia sets in the disease may already be destroying brain cells, placing severe limits on treatment options. Some large clinical trials are now testing drugs intended to clear up the brain’s cellular detritus—the aggregations of amyloid and tau proteins that may ultimately destroy brain cells. So far this approach has had decidedly mixed results. Some researchers are choosing a different direction. They have begun to ask what happens in the brain before the plaques and tangles of amyloid and tau appear—and to look at interventions that might work at this incipient disease stage. The Alzheimer’s Disease Drug Discovery Foundation has focused in recent years on funding new agents that do not target amyloid but are intended to address other manifestations of the disease, such as inflammation and the energy metabolism of neurons. At a meeting last month in Jersey City, N.J., neuroscientist Grace Stutzmann of the Chicago Medical School at Rosalind Franklin University of Medicine and Science presented her work on restoring a basic cellular process—called calcium signaling—that goes off track in Alzheimer’s. Scientific American asked her recently about her work. © 2016 Scientific American,

Keyword: Alzheimers
Link ID: 22754 - Posted: 10.13.2016

By Smitha Mundasad Health reporter People who experience frequent drops in blood pressure or dizziness when suddenly standing up are at increased risk of dementia, scientists say. Writing in Plos Medicine they suggest that less blood reaches the brain during these moments, leading to brain cell damage over time. Dementia experts say this is a "robust study" and "plausible explanation" that needs further investigation. Charities point out that factors such as smoking carry higher risks. But they say the work adds to growing evidence that changes in blood pressure have an impact on the brain. Previous studies have linked high blood pressure to types of dementia. But in this paper scientists focused on transient periods of low blood pressure - also known as postural hypotension - which become more common in older age. These episodes can sometimes leave people feeling dizzy or give them "head rushes" when standing up suddenly. Researchers from the Erasmus Medical Center, in the Netherlands, tracked 6,000 people for an average of 15 years. They found those who suffered repeated periods of low blood pressure on standing were more likely to develop dementia in the years that followed. Researcher Dr Arfan Ikram said: "Even though the effect can be seen as subtle - with an increased risk of about 4% for people with postural hypotension compared to those without it - so many people suffer from postural hypotension as they get older that it could have a significant impact on the burden of dementia across the world." He told the BBC: "If people experience frequent episodes of dizziness on standing, particularly as they get older, they should see their GPs for advice." © 2016 BBC

Keyword: Alzheimers
Link ID: 22753 - Posted: 10.13.2016

By Gareth Cook According to the American Psychiatric Association, about 5 percent of American children suffer from Attention Deficit Hyperactivity Disorder (ADHD), yet the diagnosis is given to some 15 percent of American children, many of whom are placed on powerful drugs with lifelong consequences. This is the central fact of the journalist Alan Schwarz’s new book, ADHD Nation. Explaining this fact—how it is that perhaps two thirds of the children diagnosed with ADHD do not actually suffer from the disorder—is the book’s central mystery. The result is a damning indictment of the pharmaceutical industry, and an alarming portrait of what is being done to children in the name of mental health. What prompted you to write this book? In 2011, having spent four years exposing the dangers of concussions in the National Football League and youth sports for The New York Times, I wanted another project. I had heard that high school students in my native Westchester County (just north of New York City) were snorting Adderall before the S.A.T.'s to focus during the test. I was horrified and wanted to learn more. I saw it not as a "child psychiatry" story, and not as a "drug abuse" story, but one about academic pressure and the demands our children feel they're under. When I looked deeper, it was obvious that our nationwide system of ADHD treatment was completely scattershot—basically, many doctors were merely prescribing with little thought into whether a kid really had ADHD or not, and then the pills would be bought and sold among students who had no idea what they were messing with. I asked the ADHD and child-psychiatry establishment about this, and they denied it was happening. They denied that there were many false diagnoses. They denied that teenagers were buying and selling pills. They denied that the national diagnosis rates reported by the C.D.C.—then 9.5 percent of children aged 4-17, now 11 percent and still growing—were valid. They basically denied that anything about their world was malfunctioning at all. In the end, they doth protest too much. I wrote about 10 front-page stories for The New York Times on the subject from 2012-2014. © 2016 Scientific American,

Keyword: ADHD; Drug Abuse
Link ID: 22747 - Posted: 10.12.2016