Most Recent Links
Follow us on Facebook or subscribe to our mailing list, to receive news updates. Learn more.
by Andy Coghlan HERE'S another reason to be fit and healthy. Staying free of "lifestyle diseases" and infections could put the brakes on Alzheimer's. The advice comes from teams that have pieced together how these bodily ailments create inflammation that ultimately spills over into the brain, sending its immune cells into a hyperactive, destructive state. "The idea is simple: monitoring and prompt treatment [of inflammation] could prevent the decline from Alzheimer's," said Hugh Perry of the University of Southampton, UK, as he presented the research at the Alzheimer's Research UK annual meeting in Oxford last month. As well as revealing step by step how disease and infection can aggravate and accelerate the early stages of Alzheimer's, Perry and his colleague Clive Holmes have begun a pioneering trial in 40 people to see if a drug that acts to dampen inflammation in the body can help delay the progress of the brain disease. Etanercept is already prescribed to people with rheumatoid arthritis, and works by sponging up a molecule that aggravates inflammation. According to Alzheimer's Disease International, 44 million people globally have dementia, of which Alzheimer's is the most common type. The beginnings of the disease are characterised by the appearance in the brain of plaques of amyloid proteins and tangles of tau proteins. They prompt the brain's native immune cells, the microglia, to multiply in a bid to dispose of the troublesome new debris. © Copyright Reed Business Information Ltd.
Keyword: Alzheimers
Link ID: 19536 - Posted: 04.26.2014
By MATTHEW PERRONE WASHINGTON (AP) — The Food and Drug Administration announced Friday it will convene a public meeting in October to review the risks of psychiatric and behavioral side effects with Pfizer’s anti-smoking drug Chantix. The agency said in a federal notice it will convene its panel of psychiatric drug experts to discuss the pill’s risks and how to best manage them. Since 2009 Chantix has carried the government’s strongest safety warning — a ‘‘black box’’ label — because of links to hostility, agitation, depression and suicidal thoughts. The warning was added after the FDA received dozens of reports of suicide and hundreds of reports of suicidal behavior among patients taking the smoking-cessation drug. At that time, the FDA also required Pfizer to conduct additional studies to determine the extent of the side effects. A spokeswoman for Pfizer said Friday that the company recently submitted new data to the FDA comparing the drug’s psychiatric safety to placebo and other anti-smoking techniques. The FDA first began investigating potential side effects with Chantix in 2007, the year after the twice-a-day pill hit the market. The drug’s labeling tells patients to stop taking Chantix immediately if they experience agitation, depressed mood, suicidal thinking and other behavioral changes. Doctors are advised to weigh the drug’s risks against its potential benefits in helping patients quit smoking.
Keyword: Drug Abuse; Depression
Link ID: 19535 - Posted: 04.26.2014
Does reading faster mean reading better? That’s what speed-reading apps claim, promising to boost not just the number of words you read per minute, but also how well you understand a text. There’s just one problem: The same thing that speeds up reading actually gets in the way of comprehension, according to a new study. When you read at your natural pace, your eyes move back and forth across a sentence, rather than plowing straight through to the end. Apps like Spritz or the aptly named Speed Read are built around the idea that these eye movements, called saccades, are a redundant waste of time. It’s more efficient, their designers claim, to present words one at a time in a fixed spot on a screen, discouraging saccades and helping you get through a text more quickly. This method, called rapid serial visual presentation (RSVP), has been controversial since the 1980s, when tests showed it impaired comprehension, though researchers weren’t quite sure why. With a new crop of speed-reading products on the market, psychologists decided to dig a bit more and uncovered a simple explanation for RSVP’s flaw: Every so often, we need to scan backward and reread for a better grasp of the material. Researchers demonstrated that need by presenting 40 college students with ambiguous, unpunctuated sentences ("While the man drank the water that was clear and cold overflowed from the toilet”) while following their subjects’ gaze with an eye-tracking camera. Half the time, the team crossed out words participants had already read, preventing them from rereading (“xxxxx xxx xxx drank the water …”). Following up with basic yes-no questions about each sentence’s content, they found that comprehension dropped by about 25% in trials that blocked rereading versus those that didn’t, the researchers report online this month in Psychological Science. Crucially, the drop was about the same when subjects could, but simply hadn’t, reread parts of a sentence. Nor did the results differ much when using ambiguous sentences or their less confusing counterparts (“While the man slept the water …”). Turns out rereading isn’t a waste of time—it’s essential for understanding. © 2014 American Association for the Advancement of Science.
Keyword: Language; Attention
Link ID: 19534 - Posted: 04.26.2014
Regina Nuzzo Gene therapy delivered to the inner ear can help shrivelled auditory nerves to regrow — and in turn, improve bionic ear technology, researchers report today in Science Translational Medicine1. The work, conducted in guinea pigs, suggests a possible avenue for developing a new generation of hearing prosthetics that more closely mimics the richness and acuity of natural hearing. Sound travels from its source to ears, and eventually to the brain, through a chain of biological translations that convert air vibrations to nerve impulses. When hearing loss occurs, it’s usually because crucial links near the end of this chain — between the ear’s cochlear cells and the auditory nerve — are destroyed. Cochlear implants are designed to bridge this missing link in people with profound deafness by implanting an array of tiny electrodes that stimulate the auditory nerve. Although cochlear implants often work well in quiet situations, people who have them still struggle to understand music or follow conversations amid background noise. After long-term hearing loss, the ends of the auditory nerve bundles are often frayed and withered, so the electrode array implanted in the cochlea must blast a broad, strong signal to try to make a connection, instead of stimulating a more precise array of neurons corresponding to particular frequencies. The result is an ‘aural smearing’ that obliterates fine resolution of sound, akin to forcing a piano player to wear snow mittens or a portrait artist to use finger paints. To try to repair auditory nerve endings and help cochlear implants to send a sharper signal to the brain, researchers turned to gene therapy. Their method took advantage of the electrical impulses delivered by the cochlear-implant hardware, rather than viruses often used to carry genetic material, to temporarily turn inner-ear cells porous. This allowed DNA to slip in, says lead author Jeremy Pinyon, an auditory scientist at the University of New South Wales in Sydney, Australia. © 2014 Nature Publishing Group
Keyword: Hearing; Robotics
Link ID: 19533 - Posted: 04.24.2014
by Michael Slezak Could preventing the brain shrinkage associated with depression be as simple as blocking a protein? Post-mortem analysis of brain tissue has shown that the dendrites that relay messages between neurons are more shrivelled in people with severe depression than in people without the condition. This atrophy could be behind some of the symptoms of depression, such as the inability to feel pleasure. As a result, drugs that help repair the neuronal connections, like ketamine, are under investigation. But how this shrinkage occurs has remained a mystery, limiting researchers' ability to find ways of stopping it. Ronald Duman at Yale University wondered whether a protein called REDD1, which was recently shown to reduce myelin, the fatty material that protects neurons, was the key. To find out, his team bred rats unable to produce REDD1 and exposed them to a prolonged period of unpredictable stress. In normal rats, this stress resulted in depressive-like behaviour and brain shrinkage, but Duman's rats were unaffected. In contrast, rats engineered to overproduce REDD1 became depressed and had brain shrinkage, even without being stressed. What's more, injecting normal rats with a stress hormone boosted levels of REDD1 in the brain. Giving them a drug that blocked the production of stress hormones stopped them producing the protein, even when they were externally stressed. Taken together, the experiments show that REDD1 is necessary to produce the brain shrinkage seen in stressed rats, and that stress hormones are involved in its production – offering a possible way to prevent the shrinkage. © Copyright Reed Business Information Ltd
Keyword: Depression
Link ID: 19532 - Posted: 04.24.2014
Here to stay. The Y chromosome is small compared with the X, but is required to keep levels of some genes high enough for mammals to survive. The small, stumpy Y chromosome—possessed by male mammals but not females, and often shrugged off as doing little more than determining the sex of a developing fetus—may impact human biology in a big way. Two independent studies have concluded that the sex chromosome, which shrank millions of years ago, retains the handful of genes that it does not by chance, but because they are key to our survival. The findings may also explain differences in disease susceptibility between men and women. “The old textbook description says that once maleness is determined by a few Y chromosome genes and you have gonads, all other sex differences stem from there,” says geneticist Andrew Clark of Cornell University, who was not involved in either study. “These papers open up the door to a much richer and more complex way to think about the Y chromosome.” The sex chromosomes of mammals have evolved over millions of years, originating from two identical chromosomes. Now, males possess one X and one Y chromosome and females have two Xs. The presence or absence of the Y chromosome is what determines sex—the Y chromosome contains several genes key to testes formation. But while the X chromosome has remained large throughout evolution, with about 2000 genes, the Y chromosome lost most of its genetic material early in its evolution; it now retains less than 100 of those original genes. That’s led some scientists to hypothesize that the chromosome is largely indispensable and could shrink away entirely. © 2014 American Association for the Advancement of Science.
Keyword: Sexual Behavior
Link ID: 19531 - Posted: 04.24.2014
By Linda Carroll A college education may do a lot more than provide better job opportunities — it may also make brains more resilient to trauma, a new study suggests. The more years of education people have, the more likely they will recover from a traumatic brain injury, according to the study published Wednesday in Neurology. In fact, one year after a traumatic brain injury, people with a college education were nearly four times as likely as those who hadn’t finished high school to return to work or school with no disability. Earlier studies had shown that education might have a protective effect when it comes to degenerative brain diseases like Alzheimer’s. Scientists have theorized that education leads to greater “cognitive reserve,” which allows people to overcome or compensate for brain damage. So if there are two people with the same degree of damage from Alzheimer’s, the more highly educated one will show fewer symptoms. The assumption is that education changes and expands the brain, leaving it better able to cope with challenges. “Added capacity allows us to either work around the damaged areas or to adapt,” said Eric B. Schneider, an assistant professor of surgery at the Johns Hopkins School of Medicine. Schneider and his colleagues suspected that cognitive reserve might play an equally important role in helping people rehab from acute brain damage that results from falls, car crashes and other accidents as it does in Alzheimer’s disease.
Keyword: Brain Injury/Concussion; Learning & Memory
Link ID: 19530 - Posted: 04.24.2014
By Brady Dennis, The Food and Drug Administration will for the first time regulate the booming market of electronic cigarettes, as well as cigars, pipe tobacco and hookahs, under a proposal to be released Thursday. The move would begin to place restrictions on e-cigarettes, a nearly $2 billion industry that for years has operated outside the reach of federal regulators. If adopted, the government’s plan would force manufacturers to curb sales to minors, stop handing out free samples, place health warning labels on their products and disclose the ingredients. Makers of e-cigarettes also would be banned from making health-related claims without scientific evidence. The FDA’s proposal stops short of broader restrictions sought by many tobacco-control advocates. Regulators at this point are not seeking to halt online sales of e-cigarettes, curb television advertising, or ban the use of flavorings such as watermelon, grape soda and piña colada — all tactics that critics say are aimed at attracting young smokers and that have been banned for traditional cigarettes. Those restrictions might come eventually, FDA officials said, but not before more rigorous research can establish a scientific basis for tougher rules. “Right now, for something like e-cigarettes, there are far more questions than answers,” said Mitch Zeller, director of the FDA’s Center for Tobacco Products. Thursday’s action is about expanding FDA’s authority to products that have been “rapidly evolving with no regulation whatsoever,” in order to create a foundation for broader regulation in the future, he said. “It creates the framework. We’re calling this the first step. . . . For the first time, there will be a science-based, independent regulatory agency playing a vital gate-keeping function.” © 1996-2014 The Washington Post
Keyword: Drug Abuse
Link ID: 19529 - Posted: 04.24.2014
I am a sociologist by training. I come from academic world, reading scholarly articles on topics of social import, but they're almost always boring, dry and quickly forgotten. Yet I can't count how many times I've gone to a movie, a theater production or read a novel and been jarred into seeing something differently, learned something new, felt deep emotions and retained the insights gained. I know from both my research and casual conversations with people in daily life that my experiences are echoed by many. The arts can tap into issues that are otherwise out of reach and reach people in meaningful ways. This realization brought me to arts-based research (ABR). Arts-based research is an emergent paradigm whereby researchers across the disciplines adapt the tenets of the creative arts in their social research projects. Arts-based research, a term first coined by Eliot Eisner at Stanford University in the early 90s, is based on the assumption that art can teach us in ways that other forms cannot. Scholars can take interview or survey research, for instance, and represent it through art. I've written two novels based on sociological interview research. Sometimes researchers use the arts during data collection, involving research participants in the art-making process, such as drawing their response to a prompt rather than speaking. The turn by many scholars to arts-based research is most simply explained by my opening example of comparing the experience of consuming jargon-filled and inaccessible academic articles to that of experiencing artistic works. While most people know on some level that the arts can reach and move us in unique ways, there is actually science behind this. ©2014 TheHuffingtonPost.com, Inc
Keyword: Language; Vision
Link ID: 19528 - Posted: 04.24.2014
Associated Press Diagnosed with retinitis pigmentosa as a teenager, Pontz has been almost completely blind for years. Now, thanks to a high-tech procedure that involved the surgical implantation of a "bionic eye," he has regained enough of his eyesight to catch small glimpses of his wife, grandson and cat. "It's awesome. It's exciting - seeing something new every day," Pontz said during a recent appointment at the University of Michigan Kellogg Eye Center. The 55-year-old former competitive weightlifter and factory worker is one of four people in the U.S. to receive an artificial retina since the Food and Drug Administration signed off on its use last year. The facility in Ann Arbor has been the site of all four such surgeries since FDA approval. A fifth is scheduled for next month. Retinitis pigmentosa is an inherited disease that causes slow but progressive vision loss due to a gradual loss of the light-sensitive retinal cells called rods and cones. Patients experience loss of side vision and night vision, then central vision, which can result in near blindness. Not all of the 100,000 or so people in the U.S. with retinitis pigmentosa can benefit from the bionic eye. An estimated 10,000 have vision low enough, said Dr. Brian Mech, an executive with Second Sight Medical Products Inc., the Sylmar (Los Angeles County) company that makes the device. Of those, about 7,500 are eligible for the surgery. The artificial implant in Pontz's left eye is part of a system developed by Second Sight that includes a small video camera and transmitter housed in a pair of glasses. © 2014 Hearst Communications, Inc.
Keyword: Vision; Robotics
Link ID: 19527 - Posted: 04.24.2014
It takes a lot to deter a male from wanting sex. A new study has found that male mice keep trying to copulate even when they are in pain, whereas females engage in less sex. But when given drugs that target pleasure centers in the human brain, the females again became interested. The findings could shed light on the nature of libido across various animal species. To assess how pain influences sexual desire, researchers first identified pairs of mice that wanted to have sex. “What we found early on was not all mice will mate with each other,” says clinical psychologist Melissa Farmer, who led the study while earning her Ph.D. at McGill University in Montreal, Canada. The team set up the rodents on a series of “dates,” during which a male and female were paired together for 30 minutes. Couples that copulated for most of the session were deemed compatible and moved into a cage with separate rooms. A small doorway allowed a female mouse to freely cross over from her chamber, but the male—which is larger—could not. The scientists then induced pain in males or females by applying a small dose of inflammatory compounds to the cheek, tail, foot, or genitals. The sensation would primarily be soreness, like a bad sunburn, says Farmer, who now works at Northwestern University’s Feinberg School of Medicine in Chicago, Illinois. Female mice that were in pain, whether genital or nongenital, spent 50% less time with their male partners, implying a decrease in sexual motivation. Even when they did visit their paramours, females wouldn’t allow males to mount them with the same frequency, the team reports online today in The Journal of Neuroscience. © 2014 American Association for the Advancement of Science.
Keyword: Sexual Behavior; Pain & Touch
Link ID: 19526 - Posted: 04.23.2014
|By Stephen L. Macknik and Susana Martinez-Conde The Best Illusion of the Year Contest brings scientific and popular attention to perceptual oddities. Anyone can submit an illusion to next year's contest at http://illusionoftheyear.com/submission-instructions for the rules Decked out in a mask, cape and black spandex, a fit young man leaps onto the stage, one hand raised high, and bellows, “I am Japaneeeese Bat-Maaaaaan!” in a thick accent. The performer is neither actor nor acrobat. He is a mathematician named Jun Ono, hailing from Meiji University in Japan. Ono's single bound, front and center, at the Philharmonic Center for the Arts in Naples, Fla. (now called Artis-Naples), was the opening act of the ninth Best Illusion of the Year Contest, held May 13, 2013. Four words into the event, we knew Ono had won. Aside from showcasing new science, the contest celebrates our brain's wonderful and mistaken sense that we can accurately see, smell, hear, taste and touch the world around us. In reality, accuracy is not the brain's forte, as the illusion creators competing each year will attest. Yes, there is a real world out there, and you do perceive (some of) the events that occur around you, but you have never actually lived in reality. Instead your brain gathers pieces of data from your sensory systems—some of which are quite subjective or frankly wrong—and builds a simulation of the world. This simulation, which some call consciousness, becomes the universe in which you live. It is the only thing you have ever perceived. Your brain uses incomplete and flawed information to build this mental model and relies on quirky neural algorithms to often—but not always—obviate the flaws. Let us take a spin through some of the world's top illusions and their contributions to the science of perception. (To see videos of these illusions, see ScientificAmerican.com/may2014/illusions.) © 2014 Scientific American
Keyword: Vision; Consciousness
Link ID: 19525 - Posted: 04.23.2014
Victoria Colliver, Erin Allday Women who gain too much or too little weight during pregnancy can greatly increase their baby's risk of being overweight or obese as a young child, according to a study by Kaiser Permanente researchers. Researchers examined the health records from 4,145 Northern California Kaiser members who filled out a health survey between 2007 and 2009 and subsequently gave birth. They found that women who exceeded the Institute of Medicine's revised 2009 guidelines for weight gain during pregnancy were 46 percent more likely than women who met the guidelines to have an obese or overweight child between the ages of 2 and 5 years old. Under the new guidelines, women who are obese - defined as those with a body mass index, or BMI, of 30 or higher - should gain 11 to 20 pounds. Overweight women - with BMIs between 25 and 29 - can gain 15 to 25 pounds. And normal-weight women are recommended to gain between 25 and 35 pounds. Those who are underweight - with BMIs under 18.5 - are to gain 28 to 40 pounds. Women who had a healthy BMI before their pregnancy but gained less weight than recommended were 63 percent more likely than those who met the guidelines to have an obese or overweight child. Meanwhile, healthy-weight women who exceeded the guidelines were 79 percent more likely to have an overweight child. Researchers suggested gaining too little or too much weight may permanently affect the body's mechanisms that manage energy balance and metabolism. The study, which is considered the largest to examine the new guidelines in relationship to childhood obesity, was published April 14 in the American Journal of Obstetrics and Gynecology. © 2014 Hearst Communications, Inc.
Keyword: Obesity; Development of the Brain
Link ID: 19524 - Posted: 04.23.2014
Chelsea Wald The sailfish’s sword-like bill looks as if it was made to slash at prey. But a study published today in Proceedings of the Royal Society B1 reveals that the bill is actually a multifunctional killing tool, enabling the fish to perform delicate, as well as swashbuckling, manoeuvres. By following throngs of predatory birds off the coast of Cancún, Mexico, the study’s authors were able to track Atlantic sailfish (Istiophorus albicans) hunting sardines, says co-author Alexander Wilson, a behavioural ecologist now at Carleton University in Ottawa, Canada. He and his colleagues made high-speed, high-resolution films in the open ocean over six days in 2012. Sailfish hunt in groups, taking turns to approach the ball of schooling fish. Their bodies darken and sometimes flash stripes and spots, perhaps to confuse the prey, or to signal to each other. “It’s a very orderly process,” Wilson says. “They don’t want to risk breaking their bills.” Although sailfish are among the fastest creatures in the ocean — they have been documented to swim at more than 110 kilometres per hour, or 60 knots — the new research shows that their strategy is to approach their prey slowly from behind and gently insert their bills into the school, without eliciting an evasive manoeuvre from the sardines. Then, by whipping their heads in powerful, sudden jerks, they can slash their bills left and right, with their upright fins providing stability. In fact, their bill tips slash with about the same acceleration as the tip of a swinging baseball bat, even in the water, says co-author Paolo Domenici, an environmental physiologist at the Institute for the Marine and Coastal Environment of Italy's National Research Council in Torregrande, on the island of Sardinia. The result is a scene of fishy carnage, as the surrounding water fills with iridescent fragments of sardine skin. © 2014 Nature Publishing Group,
Keyword: Pain & Touch
Link ID: 19523 - Posted: 04.23.2014
By David Grimm “We did one study on cats—and that was enough!” Those words effectively ended my quest to understand the feline mind. I was a few months into writing Citizen Canine: Our Evolving Relationship With Cats and Dogs, which explores how pets are blurring the line between animal and person, and I was gearing up for a chapter on pet intelligence. I knew a lot had been written about dogs, and I assumed there must be at least a handful of studies on cats. But after weeks of scouring the scientific world for someone—anyone—who studied how cats think, all I was left with was this statement, laughed over the phone to me by one of the world’s top animal cognition experts, a Hungarian scientist named Ádám Miklósi. We are living in a golden age of canine cognition. Nearly a dozen laboratories around the world study the dog mind, and in the past decade scientists have published hundreds of articles on the topic. Researchers have shown that Fido can learn hundreds of words, may be capable of abstract thought, and possesses a rudimentary ability to intuit what others are thinking, a so-called theory of mind once thought to be uniquely human. Miklósi himself has written an entire textbook on the canine mind—and he’s a cat person. I knew I was in trouble even before I got Miklósi on the phone. After contacting nearly every animal cognition expert I could find (people who had studied the minds of dogs, elephants, chimpanzees, and other creatures), I was given the name of one man who might, just might, have done a study on cats. His name was Christian Agrillo, and he was a comparative psychologist at the University of Padova in Italy. When I looked at his website, I thought I had the wrong guy. A lot of his work was on fish. But when I talked to him he confirmed that, yes, he had done a study on felines. Then he laughed. “I can assure you that it’s easier to work with fish than cats,” he said. “It’s incredible.” © 2014 The Slate Group LLC.
Keyword: Intelligence; Evolution
Link ID: 19522 - Posted: 04.23.2014
Josh Fischman Dogs and cats, historically, have been people’s property like a couch or a toaster. But as they’ve moved into our houses and our hearts, courts of law have begun to treat them as something more. They can inherit your estate, get an appointed lawyer if your relatives challenge that inheritance and are protected from cruel acts. Your toaster can’t do any of that. As these animals inch closer to citizens' rights, the trend is being watched with worried eyes by biomedical researchers who fear judges could extend these rights to lab animals like monkeys and rats, thereby curbing experimentation. It also disturbs veterinarians who fear a flood of expensive malpractice suits if pets are worth more than their simple economic value. David Grimm, deputy news editor for Science magazine, explores this movement in his book Citizen Canine: Our Evolving Relationship with Cats and Dogs (PublicAffairs Books, 2014), published this month. He explained to Scientific American why scientists and animal doctors have good reason to be concerned. An edited transcript of the interview follows. In what way have dogs and cats moved beyond the status of property? They can inherit money, for one thing. And since property cannot inherit property, that makes them different. Legal scholars say that is the biggest change. About 25 US states have adopted the Uniform Trust Code, which allows animals to inherit.* Also judges have granted owners of slain animals awards of emotional damages. You cannot get emotional damages from the loss of a toaster. In 2004 a California jury awarded a man named Marc Bluestone $39,000 for the loss of his dog Shane; $30,000 of that was for Shane’s special and unique value to Bluestone. © 2014 Nature Publishing Group
Keyword: Animal Rights
Link ID: 19521 - Posted: 04.23.2014
By JAMES GORMAN SAN DIEGO — Dr. Karl Deisseroth is having a very early breakfast before the day gets going at the annual meeting of the Society for Neuroscience. Thirty thousand people who study the brain are here at the Convention Center, a small city’s worth of badge-wearing, networking, lecture-attending scientists. For Dr. Deisseroth, though, this crowd is a bit like the gang at Cheers — everybody knows his name. He is a Stanford psychiatrist and a neuroscientist, and one of the people most responsible for the development of optogenetics, a technique that allows researchers to turn brain cells on and off with a combination of genetic manipulation and pulses of light. He is also one of the developers of a new way to turn brains transparent, though he was away when some new twists on the technique were presented by his lab a day or two earlier. “I had to fly home to take care of the kids,” he explained. He went home to Palo Alto to be with his four children, while his wife, Michelle Monje, a neurologist at Stanford, flew to the conference for a presentation from her lab. Now she was home and, here he was, back at the conference, looking a bit weary, eating eggs, sunny side up, and talking about the development of new technologies in science. A year ago, President Obama announced an initiative to invest in new research to map brain activity, allocating $100 million for the first year. The money is a drop in the bucket compared with the $4.5 billion the National Institutes of Health spends annually on neuroscience, but it is intended to push the development of new techniques to investigate the brain and map its pathways, starting with the brains of small creatures like flies. Cori Bargmann of Rockefeller University, who is a leader of a committee at the National Institutes of Health setting priorities for its piece of the brain initiative, said optogenetics was a great example of how technology could foster scientific progress. © 2014 The New York Times Company
Keyword: Brain imaging
Link ID: 19520 - Posted: 04.22.2014
by Bethany Brookshire Many of us have experienced that depressing sight: The bottom of the ice cream pint. You get to the end of your favorite movie and suddenly realize the ice cream is gone — and you’re far too full for comfort. We’re left wondering why we did it. But when it comes to forgetting ourselves and bingeing on the pint, the power of habit can be strong. It could be that our previous eating experiences make us helpless to our habits. A new study in rats, published April 2 in the Journal of Neuroscience, shows that long-term exposure to bursts of sweet, fatty foods produces animals that appear to seek food not out of hunger, but out of habit. And neural changes associated with habit formation accompany the behavioral changes. The results suggest that repeated binges on sugar and fat could tilt the neural balance from taking a few scoops of Cherry Garcia toward mindlessly reaching the bottom of the bowl. But while the results show us the power of habit, bad habits don’t necessarily make us food addicts. Teri Furlong and her colleagues at the University of Sydney in Australia were interested in how animals control behaviors. Some behaviors are goal-directed, while others are more efficiently taken care of with habits. Furlong describes habits as “behaviors where we are not thinking about the consequences as we do them.” Many habits can be useful things to develop — eating breakfast daily or brushing your teeth, for example. But other habits can become maladaptive, such as drug abuse — or binge eating. © Society for Science & the Public 2000 - 2013.
Keyword: Anorexia & Bulimia; Drug Abuse
Link ID: 19519 - Posted: 04.22.2014
It looks like a standardized test question: Is the sum of two numbers on the left or the single number on the right larger? Rhesus macaques that have been trained to associate numerical values with symbols can get the answer right, even if they haven’t passed a math class. The finding doesn’t just reveal a hidden talent of the animals—it also helps show how the mammalian brain encodes the values of numbers. Previous research has shown that chimpanzees can add single-digit numbers. But scientists haven’t explained exactly how, in the human or the monkey brain, numbers are being represented or this addition is being carried out. Now, a new study helps begin to answer those questions. Neurobiologist Margaret Livingstone of Harvard Medical School in Boston and her colleagues had already taught three rhesus macaques (Macaca mulatta) in the lab to associate the Arabic numbers 0 through 9 and 15 select letters with the values zero through 25. When given the choice between two symbols, monkeys reliably chose the larger to get a correspondingly larger number of droplets of water, apple juice, or orange soda as a reward. To test whether the monkeys could add these values, the researchers began giving them a choice between a sum and a single symbol rather than two single symbols. Within 4 months, the monkeys had learned how the task worked and were able to effectively add two symbols and compare the sum to a third, single symbol. To ensure that the monkeys hadn’t simply memorized every possible combination of symbols and associated a value with the combination—this wouldn’t be true addition—Livingstone’s team next taught the animals an entirely new set of symbols —Tetris-like blocks rather than letters and numbers. With the new symbols, the monkeys were again able to add—this time calculating the value of combinations they’d never seen before and confirming the ability to do basic addition, the team reports online today in the Proceedings of the National Academy of Sciences. © 2014 American Association for the Advancement of Science.
Keyword: Evolution
Link ID: 19518 - Posted: 04.22.2014
Muscle weakness from long-term alcoholism may stem from an inability of mitochondria, the powerhouses of cells, to self-repair, according to a study funded by the National Institutes of Health. In research conducted with rats, scientists found evidence that chronic heavy alcohol use affects a gene involved in mitochondrial repair and muscle regeneration. “The finding gives insight into why chronic heavy drinking often saps muscle strength and it could also lead to new targets for medication development,” said Dr. George Koob, director of the National Institute on Alcohol Abuse and Alcoholism, the NIH institute that funded the study. The study is available online in the April issue of the Journal of Cell Biology. It was led by Dr. Gyorgy Hajnoczky, M.D., Ph.D., director of Thomas Jefferson University’s MitoCare Center, Philadelphia, and professor in the Department of Pathology, Anatomy and Cell Biology. Mitochondria are cellular structures that generate most of the energy needed by cells. Skeletal muscle constantly relies on mitochondria for power. When mitochondria become damaged, they can repair themselves through a process called mitochondrial fusion — joining with other mitochondria and exchanging material such as DNA. Although well known in many other tissues, the current study is the first to show that mitochondria in skeletal muscle are capable of undergoing fusion as a repair mechanism. It had been thought that this type of mitochondrial self-repair was unlikely in the packed fibers of the skeletal muscle cells, as mitochondria have little opportunity to interact in the narrow space between the thread-like structures called myofilaments that make up muscle.
Keyword: Drug Abuse; Muscles
Link ID: 19517 - Posted: 04.22.2014