Most Recent Links

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

Featured Article

'Language Gene' Has a Partner

Few genes have made the headlines as much as FOXP2. The first gene associated with language disorders , it was later implicated in the evolution of human speech. Girls make more of the FOXP2 protein, which may help explain their precociousness in learning to talk. Now, neuroscientists have figured out how one of its molecular partners helps Foxp2 exert its effects.

The findings may eventually lead to new therapies for inherited speech disorders, says Richard Huganir, the neurobiologist at Johns Hopkins University School of Medicine in Baltimore, Maryland, who led the work. Foxp2 controls the activity of a gene called Srpx2, he notes, which helps some of the brain's nerve cells beef up their connections to other nerve cells. By establishing what SRPX2 does, researchers can look for defective copies of it in people suffering from problems talking or learning to talk.

Until 2001, scientists were not sure how genes influenced language. Then Simon Fisher, a neurogeneticist now at the Max Planck Institute for Psycholinguistics in Nijmegen, the Netherlands, and his colleagues fingered FOXP2 as the culprit in a family with several members who had trouble with pronunciation, putting words together, and understanding speech. These people cannot move their tongue and lips precisely enough to talk clearly, so even family members often can?t figure out what they are saying. It “opened a molecular window on the neural basis of speech and language,” Fisher says.

Photo credit: Yoichi Araki, Ph.D.

Links 1 - 20 of 21081

Sara Reardon Panzee the chimpanzee was a skilled communicator that could tell untrained humans where to find hidden food by using gestures and vocalizations. Austin the chimp was particularly adept with a computer, and scientists have been scanning its genome for clues to its unusual cognitive abilities. Both apes lived at a language-research centre at Georgia State University in Atlanta, and both died several years ago — but they will live on in an online database of brain scans and behavioural data from nearly 250 chimpanzees. Researchers hope to combine this trove, now in development, with a biobank of chimpanzee brains to enable scientists anywhere in the world to study the animals’ neurobiology. This push to repurpose old data is especially timely now that the US National Institutes of Health (NIH) has decided to retire its remaining research chimpanzees. The agency decommissioned more than 300 animals in 2013, but kept 50 available for research in case of a public-health emergency. Following an 18 November decision, this remaining population will also be sent to sanctuaries in the coming years. The NIH also hopes to retire another 82 chimps that it supports but does not own, says director Francis Collins. “We were on a trajectory toward zero, and today’s the day we’re at zero,” says Jeffrey Kahn, a bioethicist at Johns Hopkins University in Baltimore, Maryland, who led a 2011 study on the NIH chimp colony for the Institute of Medicine. © 2015 Nature Publishing Group

Keyword: Animal Rights; Brain imaging
Link ID: 21660 - Posted: 11.25.2015

Aimee Cunningham For a child with attention deficit hyperactivity disorder, meeting the daily expectations of home and school life can be a struggle that extends to bedtime. The stimulant medications commonly used to treat ADHD can cause difficulty falling and staying asleep, a study finds. And that can make the next day that much harder. As parents are well aware, sleep affects a child's emotional and physical well-being, and it is no different for those with ADHD. "Poor sleep makes ADHD symptoms worse," says Katherine M. Kidwell, a doctoral student in clinical psychology at the University of Nebraska, Lincoln, who led the study. "When children with ADHD don't sleep well, they have problems paying attention the next day, and they are more impulsive and emotionally reactive." Stimulant medications boost alertness, and some studies have found a detrimental effect on children's sleep. However, other studies have concluded that the stimulants' ameliorating effects improve sleep. The drugs include amphetamines such as Adderall and methylphenidate such as Ritalin. To reconcile the mixed results on stimulants and children's sleep, Kidwell and her colleagues undertook a meta-analysis, a type of study that summarizes the results of existing research. The team found nine studies that met their criteria. These studies compared children who were taking stimulant medication with those who weren't. The studies also randomly assigned children to the experimental group or the control group and used objective measures of sleep quality and quantity, such as assessing sleep in a lab setting or with a wristwatch-like monitor at home rather than a parent's report. © 2015 npr

Keyword: ADHD; Sleep
Link ID: 21659 - Posted: 11.25.2015

By Nicholas Bakalar Bright light therapy has been used effectively for seasonal affective disorder, the kind of depression that comes on at a specific time every year, often the dark days of late fall and winter, and then lifts. Now a new study has found that it may work to treat nonseasonal depression as well. Researchers randomly assigned 122 patients, 19 to 60 years old, with major depression to receive one of four treatments: 30 minutes of daily exposure to fluorescent light; 20 milligrams of Prozac daily; both light and Prozac; and a control group that received a dummy pill and exposure to an electric air purifier. The study, in JAMA Psychiatry, lasted eight weeks. Using well-validated scales that quantify depression severity, the researchers found improvements in all four groups. The difference between Prozac alone and the placebo was not statistically significant, but light therapy alone was significantly better than placebo, and light therapy with medication was the most effective treatment of all. “This is the first study to show that light treatment is an option for people with nonseasonal depression, which is much more common than seasonal depression,” said the lead author, Dr. Raymond W. Lam, a professor of psychiatry at the University of British Columbia. “Light treatment can be combined with medicine and psychotherapy, and it’s a safe treatment without a lot of side effects.” © 2015 The New York Times Company

Keyword: Depression; Biological Rhythms
Link ID: 21658 - Posted: 11.25.2015

By Virginia Morell Was that fish on your plate once a sentient being? Scientists have long believed that the animals aren’t capable of the same type of conscious thought we are because they fail the “emotional fever” test. When researchers expose birds, mammals (including humans), and at least one species of lizard to new environments, they experience a slight rise in body temperature of 1°C to 2°C that lasts a while; it’s a true fever, as if they were responding to an infection. The fever is linked to the emotions because it’s triggered by an outside stimulus, yet produces behavioral and physiological changes that can be observed. Some scientists argue that these only occur in animals with sophisticated brains that sense and are conscious of what’s happening to them. Previous tests suggested that toads and fish don’t respond this way. Now, a new experiment that gave the fish more choices shows the opposite. Researchers took 72 zebrafish and either did nothing with them or placed them alone in a small net hanging inside a chamber in their tank with water of about 27°C; zebrafish prefer water of about 28°C. After 15 minutes in the net, the team released the confined fish. They could then freely swim among the tank’s five other chambers, each heated to a different temperature along a gradient from 17.92°C to 35°C. (The previous study used a similar setup but gave goldfish a choice between only two chambers, both at higher temperatures.) The stressed fish spent more time—between 4 and 8 hours—in the warmer waters than did the control fish, and raised their body temperatures about 2°C to 4°C, showing an emotional fever, the scientists report online today in the Proceedings of the Royal Society B. Thus, their study upends a key argument against consciousness in fish, they say. © 2015 American Association for the Advancement of Science.

Keyword: Consciousness; Evolution
Link ID: 21657 - Posted: 11.25.2015

Jon Hamilton A look at the brain's wiring can often reveal whether a person has trouble staying focused, and even whether they have attention deficit hyperactivity disorder, known as ADHD. A team led by researchers at Yale University reports that they were able to identify many children and adolescents with ADHD by studying data on the strength of certain connections in their brains. "There's an intrinsic signature," says Monica Rosenberg, a graduate student and lead author of the study in Nature Neuroscience. But the approach isn't ready for use as a diagnostic tool yet, she says. The finding adds to the evidence that people with ADHD have a true brain disorder, not just a behavioral problem, says Mark Mahone, director of neuropsychology at the Kennedy Krieger institute in Baltimore. "There are measurable ways that their brains are different," he says. The latest finding came from an effort to learn more about brain connections associated with attention. Initially, the Yale team used functional MRI, a form of magnetic resonance imaging, to monitor the brains of 25 typical people while they did something really boring. Their task was to watch a screen that showed black-and-white images of cities or mountains and press a button only when they saw a city. © 2015 npr

Keyword: ADHD; Brain imaging
Link ID: 21656 - Posted: 11.24.2015

by Sarah Zielinski Call someone a “bird brain” and they are sure to be offended. After all, it’s just another way of calling someone “stupid.” But it’s probably time to retire the insult because scientists are finding more and more evidence that birds can be pretty smart. Consider these five species: We may call pigeons “flying rats” for their penchant for hanging out in cities and grabbing an easy meal. (Long before there was “pizza rat,” you know there had to be “pizza pigeons” flying around New York City.) But there may be more going on in their brains than just where to find a quick bite. Richard Levenson of the University of California, Davis Medical Center and colleagues trained pigeons to recognize images of human breast cancers. In tests, the birds proved capable of sorting images of benign and malignant tumors. In fact, they were just as good as humans, the researchers report November 18 in PLOS ONE. In keeping with the pigeons’ reputation, though, food was the reward for their performance. No one would suspect the planet’s second-best toolmakers would be small black birds flying through mountain forests on an island chain east of Australia. But New Caledonian crows have proven themselves not only keen toolmakers but also pretty good problem-solvers, passing some tests that even dogs (and pigeons) fail. For example, when scientists present an animal with a bit of meat on a long string dangling down, many animals don’t ever figure out how to get the meat. Pull it up with one yank, and the meat is still out of reach. Some animals will figure out how to get it through trial and error, but a wild New Caledonian crow solved the problem — pull, step on string, pull some more — on its first try. © Society for Science & the Public 2000 - 2015

Keyword: Intelligence; Evolution
Link ID: 21655 - Posted: 11.24.2015

By Lenny Bernstein BALTIMORE — Deep into a three-day heroin binge at a local hotel, Samantha told the newbie he was shooting too much. He wasn’t accustomed to heroin, she said, and hadn’t waited long enough since his last injection. “But he didn’t listen,” she said. Sure enough, he emerged from a visit to the bathroom, eyes glazed, and collapsed from an overdose. Samantha, who declined to give her last name to avoid trouble with her bosses at a nearby strip club, said she grabbed her naloxone, the fast-acting antidote to opioid overdoses. She was too panicked to place the atomizer on the end of the syringe, but her boyfriend wasn’t. He sprayed the mist into the nose of the unconscious drug user, who awoke minutes later. “I always have it because I’m scared to death,” said Samantha, who said she has been shooting heroin for 22 years. “I don’t want to be helpless.” As the opioid epidemic has exploded in small towns and suburbs in recent years, officials have scrambled to put naloxone in the hands of drug users’ families and friends, and to make it more widely available by equipping police officers with the drug. At the same time, thousands of lives are being saved by giving the antidote to drug users. More than 80 percent of overdose victims revived by “laypeople” were rescued by other users, most of them in the past few years, according to one national survey published in June.

Keyword: Drug Abuse
Link ID: 21654 - Posted: 11.24.2015

By Karen Weintraub Essential tremor is involuntary shaking – usually of the hands, but sometimes also of the neck, jaw, voice or legs. “Any fine tasks with the hands can be very difficult when the tremor is pronounced,” said Dr. Albert Hung, center director of the Massachusetts General Hospital National Parkinson Foundation Center of Excellence. Essential tremor can affect balance, walking, hearing and cognition, and can get worse over time, said Dr. Elan Louis, chief of the division of movement disorders at Yale School of Medicine. People with essential tremor run almost twice the risk of developing Alzheimer’s as the general population. Essential tremor appears with movement; if people let their hands sit still, they don’t tremble. That is the big difference between an essential tremor and the tremor of Parkinson’s disease, which can occur while at rest, Dr. Louis said. Essential tremor also tends to strike both hands while Parkinson’s is more one-sided at first, said Dr. Hung. The cause of essential tremor remains a mystery, though it seems to run in families. People of any age or sex can have the condition, though it is more common as people grow older. Roughly 4 percent of 40-year-olds have essential tremor, compared with about 20 percent of 90-year-olds, Dr. Louis said. Available treatments “aren’t great,” Dr. Louis said. Two medications – the beta blocker propranolol and the epilepsy drug primidone, sold under the brand name Mysoline – can reduce tremors by 10 to 30 percent, he said, but they work only in about half of patients. Deep brain stimulation – implanting electrodes into the brain to override faulty electrical signals – has been shown to markedly reduce hand tremor severity, he said. But the treatment can worsen cognitive and balance problems and “doesn’t cure the underlying disease. It merely and temporarily lessons a single symptom, which is the tremor.” © 2015 The New York Times Company

Keyword: Movement Disorders
Link ID: 21653 - Posted: 11.24.2015

By John Bohannon It may sound like a bird-brained idea, but scientists have trained pigeons to spot cancer in images of biopsied tissue. Individually, the avian analysts can't quite match the accuracy of professional pathologists. But as a flock, they did as well as trained humans, according to a new study appearing this week in PLOS ONE. Cancer diagnosis often begins as a visual challenge: Does this lumpy spot in a mammogram image justify a biopsy? And do cells in biopsy slides look malignant or benign? Training doctors and medical technicians to tell the difference is expensive and time-consuming, and computers aren't yet up to the task. To see whether a different type of trainee could do better, a team led by Richard Levenson, a pathologist and technologist at the University of California, Davis, and Edward Wasserman, a psychologist at the University of Iowa, in Iowa City, turned to pigeons. In spite of their limited intellect, the bobble-headed birds have certain advantages. They have excellent visual systems, similar to, if not better than, a human's. They sense five different colors as opposed to our three, and they don’t “fill in” the gaps like we do when expected shapes are missing. However, training animals to do a sophisticated task is tricky. Animals can pick up on unintentional cues from their trainers and other humans that may help them correctly solve problems. For example, a famous 20th century horse named Clever Hans was purportedly able to do simple arithmetic, but was later shown to be observing the reactions of his human audience. And although animals can perform extremely well on tasks that are confined to limited circumstances, overtraining on one set of materials can lead to total inaccuracy when the same information is conveyed slightly differently. © 2015 American Association for the Advancement of Science

Keyword: Vision; Learning & Memory
Link ID: 21652 - Posted: 11.21.2015

By Nicholas Bakalar Several studies have shown that there is an association between shift work and an increased risk for heart disease and diabetes. Now a new study, in the Journal of Clinical Endocrinology & Metabolism, has found a similar association in people whose sleeping schedules change on the weekend. For seven days, 447 men and women ages 30 to 54 wore devices that measured movement and tracked when they fell asleep and woke. Almost 85 percent of the group went to sleep and woke later on their days off than during the workweek. The researchers found that the greater the mismatch in sleep timing between weekdays and weekends, the higher the metabolic risk. Sleeping late on days off was linked to lower HDL (good) cholesterol, higher triglycerides, higher insulin resistance and higher body mass index. The associations persisted after controlling for physical activity, caloric intake, alcohol use and other factors. “It’s not clear yet that this is a long-term effect,” said the lead author, Patricia M. Wong, a graduate student at the University of Pittsburgh. “But we think of this as people having to sleep and work out of sync with their internal clock, and that having to be out of sync may be having these health effects.” © 2015 The New York Times Company

Keyword: Sleep
Link ID: 21651 - Posted: 11.21.2015

Human DNA is 1 to 2% Neandertal, or more, depending on where your ancestors lived. Svante Pääbo, founder of the field of paleogenetics and winner of a 2016 Breakthrough Prize, explains why that matters © 2015 Scientific American

Keyword: Evolution; Genes & Behavior
Link ID: 21650 - Posted: 11.21.2015

Ian Sample Science editor Humans buy flowers. Capuchins throw stones. Giant tortoises bellow. But the blue-capped cordon bleu, a small finch found in Africa, really knows how to win over a mate. The three-inch-high omnivores perform energetic cabaret acts to woo their partners, rattling through routines that feature head-bobbing, singing and tap dance, and often all three at once. The birds were known to sing and nod their heads to impress the opposite sex, but high speed video footage has now revealed that they spice up their displays with nifty footwork that adds percussion to their repertoire and sends vibrations racing down their perches. Scientists at Hokkaido University filmed the birds as they tried their luck with cagemates, and found that both males and females turned to tap to seduce their targets. The steps have not been seen before because they are too fast for the naked eye to spot. “Like humans, males and females of cordon-bleus are mutually choosy and both sexes need to show off,” said Masayo Soma who lead the research. “They show tap dancing throughout the courtship display, and they sometimes add songs to tap dancing.” Whether the steps and songs are coordinated is the focus of ongoing research. Footage of the birds in cabaret mode showed that an entire routine could include more than 200 steps in bursts of anything from five seconds to more than a minute. Both males and females danced more vigorously when their mate was on the same perch. Males danced more often and tapped their feet faster, but apart from that, the sexes had similar moves. © 2015 Guardian News and Media Limited

Keyword: Sexual Behavior; Animal Communication
Link ID: 21649 - Posted: 11.20.2015

By Christopher Intagliata Back in ancient times, philosophers like Aristotle were already speculating about the origins of taste, and how the tongue sensed elemental tastes like sweet, bitter, salty and sour. "What we discovered just a few years ago is that there are regions of the brain—regions of the cortex—where particular fields of neurons represent these different tastes again, so there's a sweet field, a bitter field, a salty field, etcetera." Nick Ryba [pron. Reba], a sensory neuroscientist at the National Institutes of Health. Ryba and his colleagues found that you can actually taste without a tongue at all, simply by stimulating the "taste" part of the brain—the insular cortex. They ran the experiment in mice with a special sort of brain implant—a fiber-optic cable that turns neurons on with a pulse of laser light. And by switching on the "bitter" sensing part of the brain, they were able to make mice pucker up, as if they were tasting something bitter—even though absolutely nothing bitter was touching the tongues of the mice. In another experiment, the researchers fed the mice a bitter flavoring on their tongues—but then made it more palatable by switching on the "sweet" zone of the brain. "What we were doing here was adding the sweetness, but only adding it in the brain, not in what we were giving to the mouse." Think adding sugar to your coffee—but doing it only in your mind. The findings appear in the journal Nature. © 2015 Scientific American

Keyword: Chemical Senses (Smell & Taste)
Link ID: 21648 - Posted: 11.20.2015

The town of Yarumal in Colombia is famous for all the wrong reasons: it has the world’s largest population of people with Alzheimer’s disease. In Yarumal and the surrounding state of Antioquia, 5000 people carry a gene mutation which causes early-onset Alzheimer’s – half of them will be diagnosed by the age of 45, and the other half will succumb by the time they are 65. Locals call the disease La Bobera, “the foolishness”, and the village bears uncanny parallels with the fictional Macondo in Gabriel Garcia Marquez’s novel One Hundred Years of Solitude, where people suffer memory disorders and hallucinations. But while Yarumal’s “curse” is well known, no one knew how the mutation first appeared. Now researchers have traced the ancestry of the mutation, concluding that it was probably introduced by a Spanish conquistador early in the 17th century. Ken Kosik at the University of California, Santa Barbara, and colleagues collected blood samples from 102 people in Antioquia and sequenced their genomes. The mutation causing this form of early-onset Alzheimer’s is called E280A and is found in a gene on chromosome 14 – 74 people had the mutation. Because Kosik’s team had information on the genome sequence around the mutation, they could use something called identity-by-descent analysis to determine how the people in the study were related. The analysis suggested the mutation arose from a common ancestor around 375 years ago. © Copyright Reed Business Information Ltd.

Keyword: Alzheimers; Genes & Behavior
Link ID: 21647 - Posted: 11.20.2015

Susan Milius Certain species of the crawling lumps of mollusk called chitons polka-dot their armor-plated backs with hundreds of tiny black eyes. But mixing protection and vision can come at a price. The lenses are rocky nuggets formed mostly of aragonite, the same mineral that pearls and abalone shells are made of. New analyses of these eyes support previous evidence that they form rough images instead of just sensing overall lightness or darkness, says materials scientist Ling Li of Harvard University. Adding eyes to armor does introduce weak spots in the shell. Yet the positioning of the eyes and their growth habits show how chitons compensate for that, Li and his colleagues report in the November 20 Science. Li and coauthor Christine Ortiz of MIT have been studying such trade-offs in biological materials that serve multiple functions. Human designers often need substances that multitask, and the researchers have turned to evolution’s solutions in chitons and other organisms for inspiration. Biologists had known that dozens of chiton species sprinkle their armored plates with simple-seeming eye spots. (The armor has other sensory organs: pores even tinier than the eyes.) But in 2011, a research team showed that the eyes of the West Indian fuzzy chiton (Acanthopleura granulata) were much more remarkable than anyone had realized. Their unusual aragonite lens can detect the difference between a looming black circle and a generally gray field of vision. Researchers could tell because chitons clamped their shells defensively to the bottom when a scary circle appeared but not when an artificial sky turned overall shadowy. © Society for Science & the Public 2000 - 2015

Keyword: Vision; Evolution
Link ID: 21646 - Posted: 11.20.2015

By Seth Fletcher To solve the mysteries of the brain, scientists need to delicately, precisely monitor neurons in living subjects. Brain probes, however, have generally been brute-force instruments. A team at Harvard University led by chemist Charles Lieber hopes that silky soft polymer mesh implants will change this situation. So far the researchers have tested the mesh, which is embedded with electronic sensors, in living mice. Once it has been proved safe, it could be used in people to study how cognition arises from the action of individual neurons and to treat diseases such as Parkinson's. © 2015 Scientific American

Keyword: Brain imaging
Link ID: 21645 - Posted: 11.20.2015

By Jonathan Webb Science reporter, BBC News A study of 153 brain scans has linked a particular furrow, near the front of each hemisphere, to hallucinations in schizophrenia. This fold tends to be shorter in those patients who hallucinate, compared with those who do not. It is an area of the brain that appears to have a role in distinguishing real perceptions from imagined ones. Researchers say the findings, published in Nature Communications, might eventually help with early diagnosis. The brain wrinkle, called the paracingulate sulcus or PCS, varies considerably in shape between individuals. It is one of the final folds to develop, appearing in the brain only just before birth. "The brain develops throughout life, but aspects such as whether the PCS is going to be a particularly prominent fold - or not -may be apparent in the brain at an early stage," said Jon Simons, a neuroscientist at the University of Cambridge, UK. "It might be that a reduction in this brain fold gives somebody a predisposition towards developing something like hallucinations later on in life." If further work shows that the difference can be detected before the onset of symptoms, for example, Dr Simons said it might be possible to offer extra support to people who face that elevated risk. But he stressed that schizophrenia is a complicated phenomenon. Hallucinations are one of the main symptoms, but some patients are diagnosed on the basis of other irregular thought processes. "We've known for some time that disorders like schizophrenia are not down to a single region of the brain. Changes are seen throughout various different areas. "To be able to pin such a key symptom to a relatively specific part of the brain is quite unusual." © 2015 BBC.

Keyword: Schizophrenia
Link ID: 21644 - Posted: 11.18.2015

by Bethany Brookshire Many people perceive cocaine as one of the most intense stimulant drugs available: It’s illegal, highly addictive and dangerous. Caffeine, in contrast, is the kinder, cuddlier stimulant. It’s legal, has mild effects and in forms such as coffee, it might even be good for your health. But caffeine in combination with cocaine is another story. In South America, drug distributors have started “cutting” their cocaine with caffeine. This cheaper substitute might, at first glance, seem to make the cocaine less potent. After all, there’s less of the drug there. But new data shows that when combined, cocaine and caffeine make a heck of a drug. Coca paste is a popular form of cocaine in South American countries. A smoked form of cocaine, coca paste is the intermediate product in the extraction process used to get pure cocaine out of coca leaves. Because it is smoked, the cocaine in the coca paste hits the brain very quickly, making the drug highly addictive, explains Jose Prieto, a neurochemist at the Biological Research Institute Clemente Stable in Montevideo, Uruguay. Much of the time, Coca paste isn’t acting alone, however. In a 2011 study published in Behavioral Brain Research, Prieto and his colleagues examined the contents of coca paste from police seizures. “Nearly 80 percent of the coca paste samples” were adulterated, Prieto says, “most with caffeine.” Caffeine adulteration ranged from 1 to 15 percent of the drug volume. © Society for Science & the Public 2000 - 2015.

Keyword: Drug Abuse
Link ID: 21643 - Posted: 11.18.2015

Angus Chen If you peek into classrooms around the world, a bunch of bespectacled kids peek back at you. In some countries such as China, as much as 80 percent of children are nearsighted. As those kids grow up, their eyesight gets worse, requiring stronger and thicker eyeglasses. But a diluted daily dose of an ancient drug might slow that process. The drug is atropine, one of the toxins in deadly nightshade and jimsonweed. In the 19th and early 20th centuries, atropine was known as belladonna, and fancy Parisian ladies used it to dilate their pupils, since big pupils were considered alluring at the time. A few decades later, people started using atropine to treat amblyopia, or lazy eye, since it blurs the stronger eye's vision and forces the weaker eye to work harder. As early as the 1990s, doctors had some evidence that atropine can slow the progression of nearsightedness. In some countries, notably in Asia, a 1 percent solution of atropine eyedrops is commonly prescribed to children with myopia. It's not entirely clear how atropine works. Because people become nearsighted when their eyeballs get too elongated, it's generally thought that atropine must be interfering with that unwanted growth. But as Parisians discovered long ago, the drug can have some inconvenient side effects. © 2015 npr

Keyword: Vision; Development of the Brain
Link ID: 21642 - Posted: 11.18.2015

By Gretchen Reynolds Sturdy legs could mean healthy brains, according to a new study of British twins. As I frequently have written in this column, exercise may cause robust improvements in brain health and slow age-related declines in memory and thinking. Study after study has shown correlations between physical activity, muscular health and mental acuity, even among people who are quite old. But these studies have limitations and one of them is that some people may be luckier than others. They may have been born to have a more robust brain than someone else. Their genes and early home environment might have influenced their brain health as much as or more than their exercise habits. Their genes and early home environment also might have influenced those exercise habits, as well as how their bodies and brains responded to exercise. In other words, genes and environment can seriously confound experimental results. That problem makes twins so valuable for scientific purposes. (Full disclosure, I am a twin, although not an identical one.) Twins typically share the same early home environment and many of the same genes, and if they are identical, all their genes are the same. So if one twin’s body, brain and thinking abilities begin to differ substantially over the years from their twin’s, the cause is less likely to be solely genetic or the early environment, and more likely to be attributable to lifestyle, including exercise habits. It was that possibility that recently prompted Claire Steves, a senior lecturer in twin research at King’s College London, to consider twins and their thighs. © 2015 The New York Times Company

Keyword: Alzheimers
Link ID: 21641 - Posted: 11.18.2015