Chapter 7. Life-Span Development of the Brain and Behavior

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By KEN BELSON A new study of N.F.L. retirees found that those who began playing tackle football when they were younger than 12 years old had a higher risk of developing memory and thinking problems later in life. The study, published in the medical journal Neurology by researchers at the Boston University School of Medicine, was based on tests given to 42 former N.F.L. players, ages 41 to 65, who had experienced cognitive problems for at least six months. Half the players started playing tackle football before age 12, and the other half began at 12 or older. Those former N.F.L. players who started playing before 12 years old performed “significantly worse” on every test measure after accounting for the total number of years played and the age of the players when they took the tests. Those players recalled fewer words from a list they had learned 15 minutes earlier, and their mental flexibility was diminished compared with players who began playing tackle football at 12 or older. The age of 12 was chosen as a benchmark because it is roughly the point by which brains in young boys are thought to have already undergone key periods of development. Research has shown that boys younger than 12 who injure their brains can take longer to recover and have poor cognition in childhood. The findings are likely to fuel an already fierce debate about when it is safe to allow children to begin playing tackle football and other contact sports. Youth leagues are under scrutiny for putting children at risk with head injuries. Pop Warner and many other youth leagues have added training protocols, have limited contact in practice and have adjusted weight and age limits to try to reduce head injuries and the risks associated with them. But some leagues continue to allow children as young as 5 to play tackle football. © 2015 The New York Times Company

Keyword: Brain Injury/Concussion; Development of the Brain
Link ID: 20535 - Posted: 01.29.2015

Ian Sample, science editor People who carry a mutated gene linked to longer lifespan have extra tissue in part of the brain that seems to protect them against mental decline in old age. The finding has shed light on a biological pathway that researchers now hope to turn into a therapy that slows the progression of Alzheimer’s disease and other forms of dementia. Brain scans of more than 400 healthy men and women aged 53 and over found that those who carried a single copy of a particular gene variant had a larger brain region that deals with planning and decision making. Further tests on the group found that those with an enlarged right dorsolateral prefrontal cortex (rDLPFC), as the brain region is known, fared better on a series of mental tasks. About one in five people inherits a single copy of the gene variant, or allele, known as KL-VS, which improves heart and kidney function, and on average adds about three years to human lifespan, according to Dena Dubal, a neurologist at University of California, San Francisco. Her latest work suggests that the same genetic mutation has broader effects on the brain. While having a larger rDLPFC accounted for only 12% of the improvement in people’s mental test scores, Dubal suspects the gene alters the brain in other ways, perhaps by improving the connections that form between neurons.

Keyword: Alzheimers; Genes & Behavior
Link ID: 20526 - Posted: 01.28.2015

By Eliot Marshall In perhaps the most famous study of childhood neglect, researchers have closely tracked the progress, or lack of it, in children who lived as infants in Romania’s bleak orphanages and are now teenagers. A new analysis now shows that these children, who display a variety of behavioral and cognitive problems, have less white matter in their brains than do a group of comparable children in local families. The affected brain regions include nerve bundles that support attention, general cognition, and emotion processing. The work suggests that sensory deprivation early in life can have dramatic anatomical impacts on the brain and may help explain the previously documented long-term negative affects on behavior. But there’s some potential good news: A small group of children who were taken out of orphanages and moved into foster homes at age 2 appeared to bounce back, at least in brain structure. “This is an exciting and important study,” says Harvard Medical School psychiatric researcher Martin Teicher, who directs the developmental biopsychiatry research program at McLean Hospital in Belmont, Massachusetts. The “crucial question” of whether children can recover from the setbacks of early adversity had not been answered before, he adds. The work is based on MRI scans and other measures taken in Romania by researchers at the Bucharest Early Intervention Project (BEIP). The group, headed by neurologist Charles Nelson of Harvard Medical School, was spurred to action by the collapse of Romania’s Nicolae Ceauceșcu regime in 1989, which had shunted tens of thousands of unwanted children into state-run orphanages. Nelson says that caretakers in the orphanages worked in factorylike shifts; children might see as many as 17 different caretakers in a week. Infants rarely enjoyed the one-on-one interactions that are considered essential to normal development. © 2015 American Association for the Advancement of Science

Keyword: Development of the Brain; Brain imaging
Link ID: 20524 - Posted: 01.27.2015

By ERICA GOODE A goat frolics with a baby rhinoceros. A pig nestles up to a house cat. A rat snake makes nice with the dwarf hamster originally intended as its lunch. Few things seem to capture the public imagination more reliably than friendly interactions between different species — a fact not lost on Anheuser-Busch, which during Sunday’s Super Bowl will offer a sequel to “Puppy Love,” its wildly popular 2014 Budweiser commercial about friendship between a Clydesdale and a yellow Labrador puppy. The earlier Super Bowl spot has drawn more than 55 million views on YouTube. Videos of unlikely animal pairs romping or snuggling have become so common that they are piquing the interest of some scientists, who say they invite more systematic study. Among other things, researchers say, the alliances could add to an understanding of how species communicate, what propels certain animals to connect across species lines and the degree to which some animals can adopt the behaviors of other species. “There’s no question that studying these relationships can give you some insight into the factors that go into normal relationships,” said Gordon Burghardt, a professor in the departments of psychology and ecology and evolutionary biology at the University of Tennessee, who added that one video he liked to show students was of a small and persistent tortoise tussling over a ball with a Jack Russell terrier. “Even one example raises the possibility that there’s something interesting going on here,” Dr. Burghardt said. Science has not entirely ignored unusual interactions between species. Biologists have described relationships formed to achieve a specific goal, like the cooperative hunting between groupers and moray eels. And in the mid-1900s, Konrad Lorenz and other ethologists demonstrated that during critical periods after birth, certain birds and other animals would follow the first moving object they saw, whether animal, human or machine, a phenomenon known as imprinting. Dr. Lorenz was famously photographed with a gaggle of “imprinted” geese trailing behind him. © 2015 The New York Times Company

Keyword: Aggression; Development of the Brain
Link ID: 20521 - Posted: 01.27.2015

By Will Boggs MD (Reuters Health) – There are so many different genetic forms of autism that using the singular term, autism, is misleading, researchers say. “We believe a better term to use is ‘the autisms,’ or ‘the autism spectrum disorders’ (that is, plural),” Dr. Stephen W. Scherer told Reuters Health by email. “There are many different forms of autism. In other words, autism is more of a collection of different disorders that have a common clinical manifestation.” The DNA of affected individuals varies remarkably, his team found. Two-thirds of brothers and sisters with what’s still called autism spectrum disorder, or ASD, showed different genetic changes. Scherer, from The Hospital for Sick Children in Toronto, Ontario, Canada, is part of a team that aims to identify all the genetic changes in individuals with ASD. In the U.S., the Centers for Disease Control and Prevention (CDC) estimates that 1 in 68 children (1 in 42 boys and 1 in 189 girls) have an autism spectrum disorder. Recent estimates in Europe, the CDC says, are that one to two percent of children there are affected. When Scherer's team looked for genetic changes in the entire DNA from 85 pairs of brothers and sisters with ASD and their parents, they found an average of roughly 73 genetic changes per set of DNA -- but only 36 of the 85 families (42.4 percent) had mutations that researchers could relate to genes already linked in some way to ASD. © 2015 Scientific American

Keyword: Autism
Link ID: 20520 - Posted: 01.27.2015

Over-the-counter sleeping aids and hayfever treatments can increase the risk of Alzheimer’s disease, a study has found. The sleeping medication Nytol and anti-allergy pills Benadryl and Piriton all belong to a class of drug highlighted in a warning from researchers. Each of these drugs has “anticholinergic” blocking effects on the nervous system that are said – at higher doses – to raise the likelihood of developing Alzheimer’s and other forms of dementia significantly over several years. Other drugs on the risk list include older “tricyclic” antidepressants such as doxepin, and the bladder control treatment Ditropan (oxybutynin). Many of these medicines are taken by vulnerable older people, according to the scientists, who say their findings have public health implications. Anticholinergic drugs block a nervous system chemical transmitter called acetylcholine, which can lead to side-effects including drowsiness, blurred vision and poor memory. People with Alzheimer’s disease are known to lack acetylcholine. The leader of the US study, Professor Shelly Gray, director of the geriatric pharmacy programme at the University of Washington School of Pharmacy, said: “Older adults should be aware that many medications – including some available without a prescription, such as over-the-counter sleep aids – have strong anticholinergic effects. And they should tell their healthcare providers. “Of course, no one should stop taking any therapy without consulting their healthcare provider. Healthcare providers should regularly review their older patients’ drug regimens – including over-the-counter medications – to look for chances to use fewer anticholinergic medications at lower doses.”

Keyword: Alzheimers; Sleep
Link ID: 20519 - Posted: 01.27.2015

By Elizabeth Pennisi In the animal kingdom, humans are known for our big brains. But not all brains are created equal, and now we have new clues as to why that is. Researchers have uncovered eight genetic variations that help determine the size of key brain regions. These variants may represent “the genetic essence of humanity,” says Stephan Sanders, a geneticist and pediatrician at the University of California, San Francisco, who was not involved in the study. These results are among the first to come out of the ENIGMA (Enhancing Neuro Imaging Genetics through Meta-Analysis) collaboration, involving some 300 scientists from 33 countries. They contributed MRI scans of more than 30,000 people, along with genetic and other information, most of which had been collected for other reasons. “This paper represents a herculean effort,” Sanders says. Only by pooling their efforts could the researchers track down subtle genetic influences on brain size that would have eluded discovery in smaller studies. “We were surprised we found anything at all,” says Paul Thompson, a neuroscientist at the University of Southern California in Los Angeles. But in the end, “we were able to identify hot points in the genome that help build the brain.” For the analyses, Thompson and his colleagues looked for single-letter (nucleotide base) changes in DNA that correspond to the sizes of key brain regions. One region, the hippocampus, stores memories and helps one learn. Another, called the caudate nucleus, makes it possible to ride a bike, play an instrument, or drive a car without really thinking about it. A third is the putamen, which is involved in running, walking, and moving the body as well as in motivation. The researchers did not try to examine the neocortex, the part of the brain that helps us think and is proportionally much bigger in humans than in other animals. The neocortex has crevices on its surface that look so different from one individual to the next that it’s really hard to measure consistently across labs. © 2015 American Association for the Advancement of Science

Keyword: Development of the Brain; Genes & Behavior
Link ID: 20509 - Posted: 01.22.2015

By PAULA SPAN DEDHAM, Mass. — Jerome Medalie keeps his advance directive hanging in a plastic sleeve in his front hall closet, as his retirement community recommends. That’s where the paramedics will look if someone calls 911. Like many such documents, it declares that if he is terminally ill, he declines cardiopulmonary resuscitation, a ventilator and a feeding tube. But Mr. Medalie’s directive also specifies something more unusual: If he develops Alzheimer’s disease or another form of dementia, he refuses “ordinary means of nutrition and hydration.” A retired lawyer with a proclivity for precision, he has listed 10 triggering conditions, including “I cannot recognize my loved ones” and “I cannot articulate coherent thoughts and sentences.” If any three such disabilities persist for several weeks, he wants his health care proxy — his wife, Beth Lowd — to ensure that nobody tries to keep him alive by spoon-feeding or offering him liquids. VSED, short for “voluntarily stopping eating and drinking,” is not unheard-of as an end-of-life strategy, typically used by older adults who hope to hasten their decline from terminal conditions. But now ethicists, lawyers and older adults themselves have begun a quiet debate about whether people who develop dementia can use VSED to end their lives by including such instructions in an advance directive. Experts know of just a handful of people with directives like Mr. Medalie’s. But dementia rates and numbers have begun a steep ascent, already afflicting an estimated 30 percent of those older than 85. Baby boomers are receiving a firsthand view of the disease’s devastation and burdens as they care for aging parents. They may well prove receptive to the idea that they shouldn’t be kept alive if they develop dementia themselves, predicted Alan Meisel, the director of the University of Pittsburgh’s Center for Bioethics and Health Law. © 2015 The New York Times Company

Keyword: Alzheimers
Link ID: 20495 - Posted: 01.20.2015

|By Gareth Cook What is flavor? Beginning with this simple question, the Pulitzer prize-winning journalist John McQuaid weaves a fascinating story with a beginning some half a billion years ago. In his new book, Tasty, McQuaid argues that the sense of taste has played a central role in the evolution of humans. McQuaid’s tale is about science, but also about culture, history and, one senses, our future. What made you decide to write a book about taste? I have two kids, a boy and a girl born two years apart – now teens – and a few years ago, I became fascinated with how their tastes and preferences in food differed. My son liked extremes, especially super-hot chili peppers and whole lemons and limes. My daughter hated that stuff. She preferred bland comfort foods such as mashed potatoes, pasta, cheese and rice. White foods. Both kids were also picky eaters. They liked what they liked, and it didn’t overlap (except for pizza). Speaking as a parent, this was maddening. So I wondered where these differences came from. Were they genetic? The kids had mostly the same genes. Environment? They lived in the same place. And yet clearly both genes and environment were in play somehow. So I began to look into the question, and a whole world opened up. And the basic answer to my original question is: kids are, biologically speaking, weird creatures. Pickiness seems to be programmed by evolution: it would have protected small children from eating strange, possibly poisonous items. Certain preferences, meanwhile, can develop arbitrarily and become very strong, then suddenly fade – every kid goes through phases as the brain matures and the neural networks that shape perception and behavior grow. Each person’s sense of flavor is like a snowflake or a fingerprint, in this way, shaped by partly by genes, but largely by experience. And always changing as more meals are eaten. © 2015 Scientific American

Keyword: Chemical Senses (Smell & Taste); Development of the Brain
Link ID: 20481 - Posted: 01.14.2015

Rose Eveleth Ranking pain isn’t a simple thing. The standard scale that goes from one to 10, often accompanied by smiley faces that become increasingly distressed, has been lampooned by many as being difficult to use. What does it mean to be a five? Or a three? What is that mildly sad frowny face saying? Do you have to be crying for it to really be a 10? And for some people, it’s even harder to put a number to a subjective experience. Patients with autism, for example, often struggle to express the pain they’re feeling. “We do see many members of our community who either experience altered pain perception, or who have difficulties communicating about and reporting pain,” Julia Bascom, the director of programs at the Autistic Self Advocacy Network, told me in an email. “So someone might experience acid reflux not as burning pain, but as pressure in their throat, and then struggle to interpret a numerical pain scale, or not realize they should bring the issue to the attention of those around them—or what words to use to be taken seriously.” Autism can also mean a difficulty interpreting facial expressions, so the happy and sad faces wouldn't be the most helpful visual cues. And some autistic patients aren’t verbal at all. In fact, for a long time, people thought that kids with autism didn’t feel pain at all, because they often didn’t show reactions to it the same way other people do. “They might not understand the words other people use to describe pain, even if they are feeling the exact same sensation, and their outward reactions might seem to indicate much more pain than they are actually feeling,” Bascom said. © 2015 by The Atlantic Monthly Group.

Keyword: Pain & Touch; Autism
Link ID: 20463 - Posted: 01.10.2015

|By Tori Rodriguez Coffee and tea may do more than just jolt you awake—they could also help keep your brain healthy, according to a slew of recent studies. Researchers have linked these beverages with protection from depression, Alzheimer's disease and Parkinson's disease. One large study investigated the link between depression and the intake of coffee, tea and sweet drinks [see box below]by following more than a quarter of a million older adults for 10 years. Researchers at the National Institutes of Health recorded consumption of each type of beverage in 1995 and 1996 and then compared those figures with participants' self-reported diagnoses of depression after 2000. Results showed that coffee intake was associated with a slightly lower risk for depression, according to a paper published last April in PLOS ONE. The paper found little effect from tea, but other work has shown tea to be protective. A study reported in November 2013 found older Chinese adults who regularly drank any kind of tea had a significantly smaller risk for depression: 21 percent for those who drank tea between one and five days a week and 41 percent for daily drinkers. The researchers also asked about the participants' leisure activities to ensure that the tea, and not teatime socializing, provided the protective effect. Some studies suggest that coffee and tea drinkers have lower rates of cognitive decline, too, but the evidence is mixed. Research in rodents that has focused on specific compounds in coffee and tea supports the idea that some of these chemicals reduce the risk for Alzheimer's and Parkinson's. In one such study, published online last June in Neurobiology of Aging, supplementing rats' diets with a component of coffee called eicosanoyl-5-hydroxytryptamide shielded the animals' brains against the pathological changes typical of Alzheimer's. © 2015 Scientific American,

Keyword: Drug Abuse; Alzheimers
Link ID: 20460 - Posted: 01.08.2015

by Lisa Seachrist Chiu Just before winter break, my fifth grader came home from school, opened her mouth and produced what sounded to me like a stuttering mess of gibberish. After complaining that when she spends the entire day immersed in Chinese, she sometimes can’t figure out what language to use, she carried on speaking flawless English to me and Chinese to a friend while they did their homework. Quite honestly, I had been eagerly anticipating this very day for a long time. Having worked several years to establish the Chinese language immersion elementary school my daughter attends, I could barely contain my excitement at this demonstration that she truly grasps a second language. Early language programs are hot, in no small part because, when it comes to language, kids under the age of 7 are geniuses. Like many parents, I wanted my child to be fluent in as many languages as possible so she can communicate with more people and because it gives her a prime tool to explore different cultures. Turns out, it may also benefit her brain. With the help of advanced imaging tools that reveal neural processes in specific brain structures, researchers are coalescing around the idea that fluency in more than one language heightens executive function — the ability to regulate and control cognitive processes. It’s a radical shift from just a few decades ago when psychologists routinely warned against raising children who speak two languages, lest they become confused and suffer delays in learning. © Society for Science & the Public 2000 - 2014

Keyword: Language
Link ID: 20448 - Posted: 01.01.2015

Three-year outcomes from an ongoing clinical trial suggest that high-dose immunosuppressive therapy followed by transplantation of a person's own blood-forming stem cells may induce sustained remission in some people with relapsing-remitting multiple sclerosis (RRMS). RRMS is the most common form of MS, a progressive autoimmune disease in which the immune system attacks the brain and spinal cord. The trial is funded by the National Institute of Allergy and Infectious Diseases (NIAID), part of the National Institutes of Health, and conducted by the NIAID-funded Immune Tolerance Network (ITN) External Web Site Policy. Three years after the treatment, called high-dose immunosuppressive therapy and autologous hematopoietic cell transplant or HDIT/HCT, nearly 80 percent of trial participants had survived without experiencing an increase in disability, a relapse of MS symptoms or new brain lesions. Investigators observed few serious early complications or unexpected side effects, although many participants experienced expected side effects of high-dose immunosuppression, including infections and gastrointestinal problems. The three-year findings are published in the Dec. 29, 2014, online issue of JAMA Neurology. “These promising results support the need for future studies to further evaluate the benefits and risks of HDIT/HCT and directly compare this treatment strategy to current MS therapies,” said NIAID Director Anthony S. Fauci, M.D. “If the findings from this study are confirmed, HDIT/HCT may become a potential therapeutic option for people with this often-debilitating disease, particularly those who have not been helped by standard treatments.”

Keyword: Multiple Sclerosis; Stem Cells
Link ID: 20447 - Posted: 01.01.2015

By James Gallagher Health editor, BBC News website A link between autism and air pollution exposure during pregnancy has been suggested by scientists. The Harvard School of Public Health team said high levels of pollution had been linked to a doubling of autism in their study of 1,767 children. They said tiny particulate matter, which can pass from the lungs to the bloodstream, may be to blame. Experts said pregnant women should minimise their exposure, although the link had still to be proven. Air pollution is definitely damaging. The World Health Organization estimates it causes 3.7 million deaths each year. The study, published in Environmental Health Perspectives, investigated any possible link with autism. It analysed 245 children with autism and 1,522 without. By looking at estimated pollution exposure during pregnancy, based on the mother's home address, the scientists concluded high levels of pollution were more common in children with autism. The strongest link was with fine particulate matter - invisible specks of mineral dust, carbon and other chemicals - that enter the bloodstream and cause damage throughout the body. Yet, the research is unable to conclusively say that pollution causes autism as there could be other factors that were not accounted for in the study. Consistent pattern There is a large inherited component to autism, but lead researcher Dr Marc Weisskopf said there was mounting evidence that air pollution may play a role too. BBC © 2014

Keyword: Autism; Neurotoxins
Link ID: 20428 - Posted: 12.18.2014

|By Marissa Fessenden Songbirds stutter, babble when young, become mute if parts of their brains are damaged, learn how to sing from their elders and can even be "bilingual"—in other words, songbirds' vocalizations share a lot of traits with human speech. However, that similarity goes beyond behavior, researchers have found. Even though humans and birds are separated by millions of years of evolution, the genes that give us our ability to learn speech have much in common with those that lend birds their warble. A four-year long effort involving more than 100 researchers around the world put the power of nine supercomputers into analyzing the genomes of 48 species of birds. The results, published this week in a package of eight articles in Science and 20 papers in other journals, provides the most complete picture of the bird family tree thus far. The project has also uncovered genetic signatures in song-learning bird brains that have surprising similarities to the genetics of speech in humans, a finding that could help scientists study human speech. The analysis suggests that most modern birds arose in an impressive speciation event, a "big bang" of avian diversification, in the 10 million years immediately following the extinction of dinosaurs. This period is more recent than posited in previous genetic analyses, but it lines up with the fossil record. By delving deeper into the rich data set, research groups identified when birds lost their teeth, investigated the relatively slow evolution of crocodiles and outlined the similarities between birds' and humans' vocal learning ability, among other findings. © 2014 Scientific American,

Keyword: Language; Genes & Behavior
Link ID: 20423 - Posted: 12.16.2014

By Candy Schulman My mother’s greatest fear was Alzheimer’s. She got Lewy body dementia, or LBD, instead. This little known, oddly named, debilitating illness afflicts an estimated 1.3 million Americans, the actor and comedian Robin Williams possibly among them. It is often misdiagnosed because its signs, such as hallucinations and body rigidity, do not seem like those of dementia, but in the end it robs people of themselves even more painfully. I first noticed my mother’s cognitive difficulties when she was 88. Until then, she’d led an extraordinarily active life: She was a competitive golfer with a bureau full of trophies, a painter and a sculptor. Every Hanukkah she hosted a lively feast for her eight grandchildren and nine great-grandchildren. This time, though, she needed my help planning, shopping and cooking. She was having difficulty with the guest list, trying to write every family member’s name on a piece of paper, adding up the numbers to see how many potatoes to buy for latkes. Her concentration became frayed and she kept ripping it up and starting again, close to tears. Several months before that, she had sent me a Mother’s Day card that was illustrated with childlike prose, colorful illustrations and glitter hearts. The poem on the cover was printed in a playful purple font: “For you, Mom. For kissing my boo-boos, for wiping my face. . . . For calming my fears with your loving embrace.” On Mother’s Day and the rest of the year, Mom added in a shaky script, “thanks.”

Keyword: Alzheimers
Link ID: 20422 - Posted: 12.16.2014

|By Emilie Reas If you carried a gene that doubled your likelihood of getting Alzheimer's disease, would you want to know? What if there was a simple lifestyle change that virtually abolished that elevated risk? People with a gene known as APOE e4 have a higher risk of cognitive impairment and dementia in old age. Even before behavioral symptoms appear, their brains show reduced metabolism, altered activity and more deterioration than those without the high-risk gene. Yet accumulating research is showing that carrying this gene is not necessarily a sentence for memory loss and confusion—if you know how to work it to your advantage with exercise. Scientists have long known that exercise can help stave off cognitive decline. Over the past decade evidence has mounted suggesting that this benefit is even greater for those at higher genetic risk for Alzheimer's. For example, two studies by a team in Finland and Sweden found that exercising at least twice a week in midlife lowers one's chance of getting dementia more than 20 years later, and this protective effect is stronger in people with the APOE e4 gene. Several others reported that frequent exercise—at least three times a week in some studies; up to more than an hour a day in others—can slow cognitive decline only in those carrying the high-risk gene. Furthermore, for those who carry the gene, being sedentary is associated with increased brain accumulation of the toxic protein beta-amyloid, a hallmark of Alzheimer's. More recent studies, including a 2012 paper published in Alzheimer's & Dementia and a 2011 paper in NeuroImage, found that high-risk individuals who exercise have greater brain activity and glucose uptake during a memory task compared with their less active counterparts or with those at low genetic risk. © 2014 Scientific American

Keyword: Alzheimers; Genes & Behavior
Link ID: 20421 - Posted: 12.16.2014

By Nicholas Bakalar Poor sleep in older adults may be linked to brain changes associated with dementia, a new study has found. Researchers studied 167 men who underwent sleep tests in 1999 and died by 2010. The study, in Neurology, recorded sleep duration, periods of waking up and episodes of apnea, and used pulse oximetry to measure oxygen saturation of their blood. On autopsy, they found that those in the highest one-quarter for duration of sleep at oxygen saturation of less than 95 percent were almost four times as likely to have higher levels microinfarcts, small areas of dead tissue caused by deprivation of blood supply, as those in the lowest one-quarter. Compared with those in the lowest 25 percent for duration of slow-wave (deep) sleep, those in the highest one-quarter were about a third as likely to have moderate or high levels of generalized brain atrophy. “Prior studies have shown an association between certain types of sleep disturbance and dementia,” said the lead author, Dr. Rebecca P. Gelber, an epidemiologist with the Veterans Administration in Hawaii. “These lesions may help explain the association.” © 2014 The New York Times Company

Keyword: Alzheimers; Sleep
Link ID: 20420 - Posted: 12.16.2014

By Gail Sullivan Chemicals found in food and common household products have been linked to lower IQ in kids exposed to high levels during pregnancy. Previous research linked higher exposure to chemicals called "phthalates" to poor mental and motor development in preschoolers. This study was said to be the first to report a link between prenatal exposure to the chemicals and childhood development. Researchers from Columbia University’s Mailman School of Public Health studied exposure to five types of phthalates, which are sometimes referred to as “hormone disruptors” or “endocrine disruptors.” Among these, di-n-butyl phthalate (DnBP) is used in shower curtains, raincoats, hairspray, food wraps, vinyl and pill coating, among other things — but according to the EPA, the largest source of exposure may be seafood. Di-isobutyl phthalate (DiBP) and Butylbenzyl phthalate (BBzP) are added to plastics to make them flexible. These chemicals may also used in makeup, nail polish, lacquer and explosives. The researchers linked prenatal exposure to phthalates to a more than six-point drop in IQ score compared with kids with less exposure. The study, “Persistent Associations between Maternal Prenatal Exposure to Phthalates on Child IQ at Age 7 Years," was published Wednesday in the journal PLOS One. "The magnitude of these IQ differences is troubling," one of the study’s authors, Robin Whyatt, said in a press release. "A six- or seven-point decline in IQ may have substantial consequences for academic achievement and occupational potential."

Keyword: Intelligence; Neurotoxins
Link ID: 20413 - Posted: 12.13.2014

Kelly Servick* Anesthesiologists and surgeons who operate on children have been dogged by a growing fear—that being under anesthesia can permanently damage the developing brain. Although the few studies of children knocked out for surgeries have been inconclusive, evidence of impaired development in nematodes, zebrafish, rats, guinea pigs, pigs, and monkeys given common anesthetics has piled up in recent years. Now, the alarm is reaching a tipping point. “Anything that goes from [the roundworm] C. elegans to nonhuman primates, I've got to worry about,” Maria Freire, co-chair of the U.S. Food and Drug Administration (FDA) science advisory board, told attendees at a meeting the agency convened here last month to discuss the issue. The gathering came as anesthesia researchers and regulators consider several moves to address the concerns: a clinical trial of anesthetics in children, a consensus statement about their possible risks, and an FDA warning label on certain drugs. But each step stirs debate. Many involved in the issue are reluctant to make recommendations to parents and physicians based on animal data alone. At the same time, more direct studies of anesthesia's risks in children are plagued by confounding factors, lack of funding, and ethical issues. “We have to generate—very quickly—an action item, because I don't think the status quo is acceptable,” Freire said at the 19 November meeting. “Generating an action item without having the data is where things become very, very tricky.” © 2014 American Association for the Advancement of Science

Keyword: Sleep; Development of the Brain
Link ID: 20399 - Posted: 12.06.2014