Chapter 16. None

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Sarah Boseley Health editor A man who was paralysed from below the neck after crashing his bike into a truck can once again drink a cup of coffee and eat mashed potato with a fork, after a world-first procedure to allow him to control his hand with the power of thought. Bill Kochevar, 53, has had electrical implants in the motor cortex of his brain and sensors inserted in his forearm, which allow the muscles of his arm and hand to be stimulated in response to signals from his brain, decoded by computer. After eight years, he is able to drink and feed himself without assistance. “I think about what I want to do and the system does it for me,” Kochevar told the Guardian. “It’s not a lot of thinking about it. When I want to do something, my brain does what it does.” The experimental technology, pioneered by the Case Western Reserve University in Cleveland, Ohio, is the first in the world to restore brain-controlled reaching and grasping in a person with complete paralysis. For now, the process is relatively slow, but the scientists behind the breakthrough say this is proof of concept and that they hope to streamline the technology until it becomes a routine treatment for people with paralysis. In the future, they say, it will also be wireless and the electrical arrays and sensors will all be implanted under the skin and invisible.

Keyword: Robotics
Link ID: 23423 - Posted: 03.29.2017

By Erik Vance The world’s smallest arachnid, the Samoan moss spider, is at a third of a millimeter nearly invisible to the human eye. The largest spider in the world is the goliath birdeater tarantula, which weighs 5 ounces and is about the size of a dinner plate. For reference, that is about the same difference in scale between that same tarantula and a bottlenose dolphin. And yet the bigger spider does not act in more complex ways than its tiny counterpart. “Insects and spiders and the like—in terms of absolute size—have among the tiniest brains we’ve come across,” says William Wcislo, a scientist at the Smithsonian Tropical Research Institute in Panama City. “But their behavior, as far as we can see, is as sophisticated as things that have relatively large brains. So then there’s the question: How do they do that?” No one would argue that a tarantula is as smart as a dolphin or having a really big brain is not an excellent way to perform complicated tasks. But a growing number of scientists are asking the question: Is it the only way? Do you need a big brain to hunt elusive prey, design complicated structures or produce complex social dynamics? For generations scientists have wondered how intelligent creatures developed large brains to perform complicated tasks. But Wcislo is part of a small community of scientists less interested in how brains have grown than how they have shrunk and yet shockingly still perform tasks as well or better than similar species that are much larger in size. In other words, it’s what scientists call brain miniaturization, not unlike the scaling down in size of the transistors in a computer chip. This research, in fact, may hold clues to innovative design strategies that engineers might incorporate in future generations of computers. © 2017 Scientific American

Keyword: Miscellaneous
Link ID: 23418 - Posted: 03.29.2017

Laurel Hamers SAN FRANCISCO — Millennials, rejoice: A winking-face emoji is worth a slew of ironic words. The brain interprets irony or sarcasm conveyed by an emoji in the same way as it does verbal banter, researchers reported March 26 in San Francisco at the Cognitive Neuroscience Society’s annual meeting. Researchers measured brain electrical activity of college students reading sentences ending in various emojis. For example, the sentence “You are such a jerk” was followed by an emoji that matched the words’ meaning (a frowning face), contradicted the words (a smiling face) or implied sarcasm (a winking face). Then the participants assessed the veracity of the sentence—was the person actually a jerk? Some participants read the sentence literally no matter what, said Benjamin Weissman, a linguist at the University of Illinois at Urbana-Champaign. But people who said emojis influenced their interpretation showed different brain activity in response to sentences with a winking emoji than ones with other emojis. A spike in electrical activity occurred 200 milliseconds after reading winky-face sentences, followed by another spike at 600 milliseconds. A similar electrical pattern has been noted in previous studies in which people listened to sentences where intonation conveyed a sarcastic rather than literal interpretation of the words. That peak at 600 milliseconds has been linked to reassessment. It’s as if the brain reads the sentence one way, sees the emoji and then updates its interpretation to fit the new information, Weissman said. |© Society for Science & the Public 2000 - 2017

Keyword: Emotions
Link ID: 23417 - Posted: 03.29.2017

By Lizzie Wade Ask any biologist what makes primates special, and they’ll tell you the same thing: big brains. Those impressive noggins make it possible for primates from spider monkeys to humans to use tools, find food, and navigate the complex relationships of group living. But scientists disagree on what drove primates to evolve big brains in the first place. Now, a new study comes to an unexpected conclusion: fruit. “The paper is enormously valuable,” says Richard Wrangham, a biological anthropologist at Harvard University who was not involved in the work. For the last 20 years, many scientists have argued that primates evolved bigger brains to live in bigger groups, an idea known as the “social brain hypothesis.” The new study’s large sample size and robust statistical methods suggest diet and ecology deserve more attention, Wrangham says. But not everyone is convinced. Others say that although a nutrient-rich diet allows for bigger brains, it wouldn’t be enough by itself to serve as a selective evolutionary pressure. When the authors compare diet and social life, “they’re comparing apples and oranges,” says Robin Dunbar, an evolutionary psychologist at the University of Oxford in the United Kingdom and one of the original authors of the social brain hypothesis. Alex DeCasien, the new study’s author, didn’t set out to shake up this decades-long debate. The doctoral student in biological anthropology at New York University in New York City wanted to tease out whether monogamous primates had bigger or smaller brains than more promiscuous species. She collected data about the diets and social lives of more than 140 species across all four primate groups—monkeys, apes, lorises, and lemurs—and calculated which features were more likely to be associated with bigger brains. To her surprise, neither monogamy nor promiscuity predicted anything about a primate’s brain size. Neither did any other measure of social complexity, such as group size. The only factor that seemed to predict which species had larger brains was whether their diets were primarily leaves or fruit, DeCasien and her colleagues report today in Nature Ecology & Evolution. © 2017 American Association for the Advancement of Science

Keyword: Evolution; Genes & Behavior
Link ID: 23416 - Posted: 03.28.2017

By MATT RICHTEL LOS ANGELES — Nine days after Nikolas Michaud’s latest heroin relapse, the skinny 27-year-old sat on a roof deck at a new drug rehabilitation clinic here. He picked up a bong, filled it with a pinch of marijuana, lit the leaves and inhaled. All this took place in plain view of the clinic’s director. “The rules here are a little lax,” Mr. Michaud said. In almost any other rehab setting in the country, smoking pot would be a major infraction and a likely cause for being booted out. But here at High Sobriety — the clinic with a name that sounds like the title of a Cheech and Chong comeback movie — it is not just permitted, but part of the treatment. The new clinic is experimenting with a concept made possible by the growing legalization of marijuana: that pot, rather than being a gateway into drugs, could be a gateway out. A small but growing number of pain doctors and addiction specialists are overseeing the use of marijuana as a substitute for more potent and dangerous drugs. Dr. Mark Wallace, chairman of the division of pain medicine in the department of anesthesia at the University of California, San Diego, said over the last five years he has used marijuana to help several hundred patients transition off opiates. “The majority of patients continue to use it,” he said of marijuana. But he added that they tell him of the opiates: “I feel like I was a slave to that drug. I feel like I have my life back.” Dr. Wallace is quick to note that his evidence is anecdotal and more study is needed. Research in rats, he said, supports the idea that the use of cannabinoids can induce withdrawal from heavier substances. But in humans? © 2017 The New York Times Company

Keyword: Drug Abuse
Link ID: 23415 - Posted: 03.28.2017

By Des Bieler Brain injuries are a danger in many sports, but for none more than football and its most profitable enterprise, the National Football League. The NFL is spending hundreds of millions of dollars on a concussion-lawsuit settlement and has poured tens of millions into research on measuring and preventing head trauma. Now some scientists are using an NFL-backed technology to examine blood samples for proteins that have been shown to correlate with concussion and other injuries. One of the most intriguing of these proteins, which could help create better tests for traumatic brain injury, is called neurofilament light — or, as it’s known for short, NFL. That’s right, a protein called “NFL” may wind up helping the NFL address its most vexing medical problem. “It's just a remarkable coincidence,” said Kevin Hrusovsky, chief executive of Quanterix, a company that has received $800,000 in grant money from the NFL through the league's “Head Health Challenge” partnership with GE. Quanterix's technology allows users to zero in on molecules with such precision that Hrusovsky likened it to “being able to see a grain of sand in 2,000 Olympic-size swimming pools.” That is crucial, because only tiny amounts of the proteins, referred to as “biomarkers,” dribble across the blood-brain barrier from the cerebrospinal fluid around the brain, where they would be found in larger quantities. The ability to spot sub-concussion injuries is important because they often go undetected by conventional methods and yet are increasingly seen as major threats to long-term health. The problem with simply sampling athletes' cerebrospinal fluid, of course, is that requires a lumbar puncture, or spinal tap, which is a lot to ask in the middle of a football game (or in any other time and place, for that matter). Pricking an athlete's finger for a blood test and getting the results 15 to 20 minutes later makes for a much more reasonable process, albeit one still a long way from implementation. © 1996-2017 The Washington Post

Keyword: Brain Injury/Concussion
Link ID: 23414 - Posted: 03.28.2017

By Scott Barry Kaufman Rarely do I read a scientific paper that overwhelms me with so much excitement, awe, and reverence. Well, a new paper in Psychological Science has really got me revved up, and I am bursting to share their findings with you! Most research on mind-wandering and daydreaming draws on either two methods: strict, laboratory conditions that ask people to complete boring, cognitive tasks and retrospective surveys that ask people to recall how often they daydream in daily life. It has been rather difficult to compare these results to each other; laboratory tasks aren't representative of how we normally go about our day, and surveys are prone to memory distortion. In this new, exciting study, Michael Kane and colleagues directly compared laboratory mind-wandering with real-life mind wandering within the same person, and used an important methodology called "experience-sampling" that allows the researcher to capture people's ongoing stream of consciousness. For 7 days, 8 times a day, the researchers randomly asked 274 undergraduates at North Carolina at Greensboro whether they were mind-wandering and the quality of their daydreams. They also asked them to engage in a range of tasks in the laboratory that assessed their rates of mind-wandering, the contents of their off-task thoughts, and their "executive functioning" (a set of skills that helps keep things in memory despite distractions and focus on the relevant details). What did they find? © 2017 Scientific American

Keyword: Attention
Link ID: 23409 - Posted: 03.27.2017

Austin Frakt By middle age, the lenses in your eyes harden, becoming less flexible. Your eye muscles increasingly struggle to bend them to focus on this print. But a new form of training — brain retraining, really — may delay the inevitable age-related loss of close-range visual focus so that you won’t need reading glasses. Various studies say it works, though no treatment of any kind works for everybody. The increasing difficulty of reading small print that begins in middle age is called presbyopia, from the Greek words for “old man” and “eye.” It’s exceedingly common, and despite the Greek etymology, women experience it, too. Every five years, the average adult over 30 loses the ability to see another line on the eye reading charts used in eye doctors’ offices. By 45, presbyopia affects an estimated 83 percent of adults in North America. Over age 50, it’s nearly universal. It’s why my middle-aged friends are getting fitted for bifocals or graduated lenses. There are holdouts, of course, who view their cellphones and newspapers at arm’s length to make out the words. The decline in vision is inconvenient, but it’s also dangerous, causing falls and auto accidents. Bifocals or graduated lenses can help those with presbyopia read, but they also contribute to falls and accidents because they can impair contrast sensitivity (the ability to distinguish between shades of gray) and depth perception. I’m 45. I don’t need to correct my vision for presbyopia yet, but I can tell it’s coming. I can still read the The New York Times print edition with ease, but to read text in somewhat smaller fonts, I have to strain. Any year now, I figured my eye doctor would tell me it was time to talk about bifocals. Or so I thought. Then I undertook a monthslong, strenuous regimen designed to train my brain to correct for what my eye muscles no longer can manage. © 2017 The New York Times Company

Keyword: Vision
Link ID: 23407 - Posted: 03.27.2017

By STEPH YIN For animals that hibernate, making it to spring is no small feat. Torpor — the state of reduced bodily activity that occurs during hibernation — is not restful. By the time they emerge, hibernating animals are often sleep-deprived: Most expend huge bursts of energy to arouse themselves occasionally in the winter so their body temperatures don’t dip too low. This back-and-forth is exhausting, and hibernators do it with little to no food and water. By winter’s end, some have shed more than half their body weight. But just because it’s spring doesn’t mean it’s time to celebrate. Spring means getting ready for the full speed of summer — and after spending a season in slow motion, that requires some ramping up. Here’s a look at what different animals have on the agenda after coming out of winter’s slumber. Black bears emerge from their dens in April, but stay lethargic for weeks. During this so-called walking hibernation, they sleep plenty and don’t roam very far. Though they have lost up to one-third of their body weight over winter, they don’t have a huge appetite right away — their metabolism is not yet back to normal. They snack mostly on pussy willows and bunches of snow fleas. In January or February, some females give birth, typically to two or three cubs. New mothers continue to hibernate, but they go in and out of torpor, staying alert enough to respond to their cubs’ cries. When they emerge from their dens, mama bears find trees with rough bark that her cubs can easily climb for safety. “Slowly, the bears’ metabolism gears up to normal, active levels,” said Lynn Rogers, a bear expert and principal biologist at the Wildlife Research Institute, a nonprofit in Minnesota. “When plants start sprouting on the forest floor, that’s when they start really moving around.” © 2017 The New York Times Company

Keyword: Biological Rhythms
Link ID: 23406 - Posted: 03.25.2017

By Diana Kwon Astrocytes, star-shape glial cells in the brain, were once simply considered support cells for neurons. However, neuroscientists have recently realized they have many other functions: studies have shown that astrocytes are involved in metabolism, learning, and more. In the latest study to investigate astrocytes’ roles in the brain, researchers confirmed these cells played a key role in regulating mouse circadian rhythms. The team’s results were published today (March 23) in Current Biology. “Recent results have indicated that [glia] are actively modulating synaptic transmission, the development of the nervous system, and changes in the nervous system in response to changes in the environment,” said coauthor Erik Herzog, a neuroscientist at Washington University in St. Louis. “So circadian biologists recognized that the system that we study in the brain also had astrocytes and have wondered what role that they might play.” In 2005, Herzog’s team published a seminal study linking glia to mammalian circadian rhythms. By investigating rat and mouse astrocytes in a dish, the researchers discovered that these glial cells showed circadian rhythms in gene expression. Since then, several independent groups have reported evidence to suggest that astrocytes help regulate daily rhythms. However, linking astrocytes to circadian behaviors in mice remained difficult. “I had several folks in the lab over many years [who] were unable to find the tools that would allow us to answer the question definitively: Do astrocytes play a role in scheduling our day?” Herzog recalled. “Then, within the last year or so, some new tools . . . became available for us.”. © 1986-2017 The Scientist

Keyword: Biological Rhythms; Glia
Link ID: 23405 - Posted: 03.25.2017

USA Today Network Josh Hafner , For college students, new parents and employees dogged by deadlines, the all-nighter is nothing new. But going without sleep leaves you basically drunk, putting you at the equivalent of a .1% blood alcohol content as you drive to work, make decisions and interact with others. “The first thing that goes is your ability to think," said Joseph Ojile, M.D., a board member with the National Sleep Foundation. Judgement, memory and concentration all suffer impairment by the body's 17th hour without sleep, he said. “We know at 17 hours, you're at .08% blood alcohol level," he said, the legal standard for drunk driving. "At 24 hours, you’re at 0.1%." Coordination deteriorates as well in those intervening hours, said Ojile, a professor at Saint Louis University School of Medicine. Irritability sets in, too. Pain becomes more acute and the immune system suffers, he said, leaving the body more open to infection. "Here’s the worst part about the lack of judgement," Ojile said. "The person is unaware of their impairment. How scary is that? ‘I’m fine, I’ll just drive home. I’ll do my work at the nuclear plant, no problem. Or fly the plane, no problem.’" It's not entirely clear how the effects worsen past 24 hours, Ojile said, other than they do. The brain starts shutting down in trance-like microsleeps, 15- to 30-second spells that occur without the person noticing. Eventually, not sleeping results in death.

Keyword: Sleep
Link ID: 23404 - Posted: 03.25.2017

By Linda Searing The precise cause, or causes, of dementias such as Alzheimer’s disease remain unclear, but one theory points to molecules called free radicals that can damage nerve cells. This damage, called oxidative stress, may lead to changes in the brain over time that result in dementia. Might antioxidant supplements prevent this? The study involved 7,540 men 60 and older (average age, 67) with no indications of dementia and no history of serious head injury, substance abuse or neurological conditions that affect cognition. They were randomly assigned to take vitamin E (an antioxidant, 400 International Units daily), selenium (also an antioxidant, 200 micrograms daily), both vitamin E and selenium or a placebo. The men also had their memory assessed periodically. In just over five years, 325 of the men (about 4 percent) developed dementia, with essentially no difference in the rate of occurrence between those who took one or both supplements and those who took the placebo. The researchers concluded that the antioxidant supplements “did not forestall dementia and are not recommended as preventive agents.” Who may be affected? Older men. The risk for dementia increases with advanced age and is most common among the very elderly. Memory loss is the most well-known symptom, but people with dementia may also have problems thinking, speaking, controlling emotions and doing daily activities such as getting dressed and eating. Alzheimer’s disease is the most common type of dementia, affecting more than 5.5 million Americans, including more than 10 percent of those 65 and older and more women than men. Caveats Participants took the supplements for a relatively short time. Whether the findings would apply to women was not tested. The study did not prove that the dementia developed by the study participants was caused by oxidative stress. © 1996-2017 The Washington Post

Keyword: Alzheimers
Link ID: 23403 - Posted: 03.25.2017

If your parrot is feeling glum, it might be tweetable. Wild keas spontaneously burst into playful behaviour when exposed to the parrot equivalent of canned laughter – the first birds known to respond to laughter-like sounds. The parrots soared after one another in aerobatic loops, exchanged foot-kicking high fives in mid-air and tossed objects to each other, in what seems to be emotionally contagious behaviour. And when the recording stops, so does the party, and the birds go back to whatever they had been doing. We already knew that these half-metre-tall parrots engage in playful behaviour, especially when young. What’s new is that a special warbling call they make has been shown to trigger behaviour that seems to be an equivalent of spontaneous, contagious laughter in humans. Moreover, it’s not just the young ones that respond, adults of both sexes join in the fun too. Raoul Schwing of the University of Veterinary Medicine in Vienna, Austria, and his team played 5-minute recordings to gatherings of between two and a dozen wild keas on a mountainside of New Zealand’s Arthur’s Pass National Park, on the southern island. The group played recordings of the warble sound, or other sounds, including two other frequent kea sounds – a screech and a whistle – plus the alarm call of a local robin species and a bland tone. © Copyright Reed Business Information Lt

Keyword: Emotions; Evolution
Link ID: 23400 - Posted: 03.24.2017

By DENISE GRADY Dr. Lewis P. Rowland, a neurologist who made fundamental discoveries in nerve and muscle diseases and clashed with government investigators during the McCarthy era, died on March 16 in Manhattan. He was 91. The cause was a stroke, his son Steven said. Dr. Rowland, the chairman of Columbia University’s neurology department for 25 years, died at NewYork-Presbyterian/Columbia University Medical Center. Dr. Rowland was a prolific researcher and writer, with nearly 500 published scientific articles that focused on devastating neuromuscular diseases, including muscular dystrophy, myasthenia gravis and many rare syndromes. He took a special interest in amyotrophic lateral sclerosis, or A.L.S., also called Lou Gehrig’s disease, which causes degeneration of nerves in the brain and spinal cord, leading to weakness, paralysis and death. Dr. Rowland led research teams that delineated a number of uncommon diseases that had been poorly understood. They also found that in a subgroup of A.L.S. patients, the disease was linked to lymphoma, a cancer of the immune system. Other studies led to the discovery that a gene defect causes an unusual form of dementia in some patients with A.L.S. In myasthenia gravis, Dr. Rowland and his colleagues documented its high death rate and helped identify treatments that prolonged survival. In the 1970s, long before the tools existed to study DNA’s role in neurological diseases like A.L.S., Alzheimer’s and Parkinson’s, Dr. Rowland predicted correctly that genetics would be the key to understanding them. One of his accomplishments at Columbia was the expansion in 1982 of an intensive care unit that added beds for patients who were severely ill with neurological disorders. Before then, it was often difficult to find I.C.U. space for them. © 2017 The New York Times Company

Keyword: ALS-Lou Gehrig's Disease ; Muscles
Link ID: 23399 - Posted: 03.24.2017

A study in Neurology suggests that analyzing levels of the protein p75ECD in urine samples from people with amyotrophic lateral sclerosis (ALS) may help monitor disease progression as well as determine the effectiveness of therapies. The study was supported by National Institute of Neurological Disorders and Stroke (NINDS) and National Center for Advancing Translational Sciences (NCATS), both part of the National Institutes of Health. Mary-Louise Rogers, Ph.D., senior research fellow at Flinders University in Adelaide, Australia, and Michael Benatar, M.D., Ph.D, professor of neurology at the University of Miami, and their teams, discovered that levels of urinary p75 ECD increased gradually in patients with ALS as their disease progressed over a 2-year study period. “It was encouraging to see changes in p75ECD over the course of the study, because it suggests an objective new method for tracking the progression of this aggressive disease,” said Amelie Gubitz, Ph.D., program director at NINDS. “In addition, it indicates the possibility of assessing whether levels of that protein decrease while patients try future treatments, to tell us whether the therapies are having any beneficial effects.” Further analysis of the samples from 54 patients revealed that those who began the study with lower levels of urinary p75ECD survived longer than did patients who had higher levels of the protein initially, suggesting that it could be a prognostic marker of the disease and may inform patients about their illness. Dr. Benatar and his team noted that this may be useful in selecting participants for clinical trials and in improving study design.

Keyword: ALS-Lou Gehrig's Disease
Link ID: 23396 - Posted: 03.23.2017

By Jia Naqvi A drug frequently prescribed for pain is no more effective than a placebo at controlling sciatica, a common source of pain in the lower back and leg, according to a study published Wednesday in the New England Journal of Medicine. The researchers at the George Institute for Global Health in Australia followed 209 sciatica patients in Sydney who were randomly assigned to receive either the drug pregabalin, more commonly known as Lyrica, or a placebo. The results showed no significant differences in leg pain intensity between the group on the placebo and that on Lyrica after eight weeks taking the drug or during the rest of the year on follow-up exams. Similarly, there were no differences for other outcomes such as back pain, quality of life and degree of disability. After Lyrica was approved in 2004, it has become the most commonly prescribed medicine for neuropathic pain, which is caused by damage to the nervous system. The drug was ranked as the 19th-highest-earning pharmaceutical in 2015, with worldwide sales rising annually at a rate of 9 percent and sale revenue of more than $3 billion in 2015 in the United States. “We have seen a huge rise in the amount of prescriptions being written each year for patients suffering from sciatica. It’s an incredibly painful and disabling condition, so it’s no wonder people are desperate for relief and medicines such as pregabalin have been widely prescribed,” Christine Lin, one of the authors of the study and an associate professor at the George Institute for Global Health, said in a news release. © 1996-2017 The Washington Post

Keyword: Pain & Touch
Link ID: 23395 - Posted: 03.23.2017

By Sam Wong It takes brains to choose a good partner. In one of the first experiments to look at the cognitive demands of choosing a mate, female guppies with big brains showed a preference for more colourful males, while those with smaller brains showed no preference. In guppies, like most animals, females are choosy about who to mate with, since they invest more in their offspring than males, which don’t help care for them. They tend to prefer males with striking colour patterns and big tails, traits that have been linked to good foraging ability and health. By choosing a male with these qualities, female guppies give their offspring a good chance of inheriting the same useful traits. Despite this, females often go on to make different choices. Alberto Corral López and colleagues at Stockholm University wanted to find out if brain size could account for this. Corral López and his team tested 36 females bred to have large brains, 36 bred to have small brains, and 16 females similar to guppies found in the wild. Previous studies have shown that large-brained guppies perform better in cognitive tests, suggesting that they are smarter. Each female was given the opportunity to associate with two males, one more colourful than the other. Females are known to spend more time close to males they would prefer to mate with, so the team timed how long they spent with each male. © Copyright Reed Business Information Ltd

Keyword: Sexual Behavior; Evolution
Link ID: 23394 - Posted: 03.23.2017

By Mo Costandi This map of London shows how many other streets are connected to each street, with blue representing simple streets with few connecting streets and red representing complex streets with many connecting streets. Credit: Joao Pinelo Silva The brain contains a built-in GPS that relies on memories of past navigation experiences to simulate future ones. But how does it represent new environments in order to determine how to navigate them successfully? And what happens in the brain when we enter a new space, or use satellite navigation (SatNav) technology to help us find our way around? Research published Tuesday in Nature Communications reveals two distinct brain regions that cooperate to simulate the topology of one’s environment and plan future paths through it when one is actively navigating. In addition, the research suggests both regions become inactive when people follow SatNav instructions instead of using their spatial memories. In a previous study researchers at University College London took participants on a guided tour through the streets of London’s Soho district and then used functional magnetic resonance imaging (fMRI) to scan their brains as they watched 10 different simulations of navigating those streets. Some of the movies required them to decide at intersections which way would be the shortest path to a predetermined destination; others came with instructions about which way to go at each junction. © 2017 Scientific American,

Keyword: Learning & Memory
Link ID: 23391 - Posted: 03.22.2017

Hannah Devlin Scientists have developed a new genetic test for Alzheimer’s risk that can be used to predict the age at which a person will develop the disease. A high score on the test, which is based on 31 genetic markers, can translate to being diagnosed many years earlier than those with a low-risk genetic profile, the study found. Those ranked in the top 10% in terms of risk were more than three times as likely to develop Alzheimer’s during the course of the study, and did so more than a decade before those who ranked in the lowest 10%. Strobe lighting provides a flicker of hope in the fight against Alzheimer’s Read more Rahul Desikan, of the University of California – who led the international effort, said the test could be used to calculate any individual’s risk of developing Alzheimer’s that year. “That is, if you don’t already have dementia, what is your yearly risk for AD onset, based on your age and genetic information,” he said. The so-called polygenic hazard score test was developed using genetic data from more than 70,000 individuals, including patients with Alzheimer’s disease and healthy elderly people. It is already known that genetics plays a powerful role in Alzheimer’s. Around a quarter of patients have a strong family history of the disease, and scientists have shown this is partly explained by a gene called ApoE, which comes in three versions, and is known to have a powerful influence on the risk of getting the most common late-onset type of Alzheimer’s. One version of ApoE appears to reduce risk by up to 40%, while those with two copies (one from each parent) of the high-risk version can increase risk by 12 times.

Keyword: Alzheimers
Link ID: 23390 - Posted: 03.22.2017

By KIM SEVERSON SONOMA, Calif. — The first thing Paula Wolfert wants to make a guest is coffee blended with butter from grass-fed cows and something called brain octane oil. She waves a greasy plastic bottle of the oil around her jumble of a kitchen like a preacher who has taken up a serpent. Never mind that this is the woman who introduced tagines, Aleppo pepper and cassoulet to American kitchens, wrote nine cookbooks and once possessed a palate the food writer Ruth Reichl declared the best she’d ever encountered. Ms. Wolfert, 78, has dementia. She can’t cook much, even if she wanted to. Which, by the way, she doesn’t. She learned she probably had Alzheimer’s disease in 2013, but she suspected something wasn’t right long before. Words on a page sometimes made no sense. Complex questions started to baffle her. Since she has always been an audacious and kinetic conversationalist with a touch of hypochondria, friends didn’t notice anything was wrong. Doctors spoke of “senior moments.” But she knew. One day, Ms. Wolfert went to make an omelet for her husband, the crime novelist William Bayer. She had to ask him how. The woman who once marched up to the French chef Jean-Louis Palladin and told him a dish didn’t have enough salt can no longer taste the difference between a walnut and a pecan, or smell whether the mushrooms are burning. The list of eight languages she once understood has been reduced to English. Maybe 40 percent of the words she knew have evaporated. “What am I going to do, cry about it?” Ms. Wolfert said in an interview at her home this month, the slap of her Brooklyn accent still sharp. After all, she points out, her first husband left her in Morocco with two small children and $2,000: “I cried for 20 minutes and I thought, ‘This isn’t going to do any good.’” © 2017 The New York Times Company

Keyword: Alzheimers
Link ID: 23389 - Posted: 03.22.2017