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By ALEX HALBERSTADT Dr. Vint Virga likes to arrive at a zoo several hours before it opens, when the sun is still in the trees and the lanes are quiet and the trash cans empty. Many of the animals haven’t yet slipped into their afternoon malaise, when they retreat, appearing to wait out the heat and the visitors and not do much of anything. Virga likes to creep to the edge of their enclosures and watch. He chooses a spot and tries not to vary it, he says, “to give the animals a sense of control.” Sometimes he watches an animal for hours, hardly moving. That’s because what to an average zoo visitor looks like frolicking or restlessness or even boredom looks to Virga like a lot more — looks, in fact, like a veritable Russian novel of truculence, joy, sociability, horniness, ire, protectiveness, deference, melancholy and even humor. The ability to interpret animal behavior, Virga says, is a function of temperament, curiosity and, mostly, decades of practice. It is not, it turns out, especially easy. Do you know what it means when an elephant lowers her head and folds her trunk underneath it? Or when a zebra wuffles, softly blowing air between her lips; or when a colobus monkey snuffles, sounding a little like a hog rooting in the mud; or when a red fox screams, sounding disconcertingly like an infant; or when red fox kits chatter at one another; or when an African wild dog licks and nibbles at the lips of another; or when a California sea lion resting on the water’s surface stretches a fore flipper and one or both rear flippers in the air, like a synchronized swimmer; or when a hippopotamus “dung showers” by defecating while rapidly flapping its tail? Virga knows, because it is his job to know. He is a behaviorist, and what he does, expressed plainly, is see into the inner lives of animals. The profession is an odd one: It is largely unregulated, and declaring that you are an expert is sometimes enough to be taken for one. Most behaviorists are former animal trainers; some come from other fields entirely. Virga happens to be a veterinarian, very likely the only one in the country whose full-time job is tending to the psychological welfare of animals in captivity. © 2014 The New York Times Company
|By Jessica Wright and SFARI.org CHD8, a gene that regulates the structure of DNA, is the closest thing so far to an ‘autism gene,’ suggests a study published today in Cell. People with mutations in this gene all have the same cluster of symptoms, including a large head, constipation and characteristic facial features; nearly all also have have autism. Autism is notoriously heterogeneous, perhaps involving mutations in any of hundreds of genes. Typically, researchers begin by studying people with similar symptoms and working backward to identify what causes those symptoms. But that approach has not been particularly productive. “We’ve tried for so long to identify subtypes of autism based on behavior alone and we’ve done abysmally at that,” says lead researcher Raphael Bernier, associate professor of psychiatry at the University of Washington in Seattle. The reverse approach — that is, beginning with people who all have mutations in the same gene and characterizing their symptoms — may prove to be more useful for simplifying autism’s complexity. For example, identifying subtypes of autism may help researchers develop drugs tailored to that particular cause, says Evan Eichler, professor of genome sciences at the University of Washington, who spearheaded the genetics side of the study. “I think the most important realization is that not all autisms are created equal,” he says. © 2014 Scientific American,
By GABRIELLE GLASER When their son had to take a medical leave from college, Jack and Wendy knew they — and he — needed help with his binge drinking. Their son’s psychiatrist, along with a few friends, suggested Alcoholics Anonymous. He had a disease, and in order to stay alive, he’d have to attend A.A. meetings and abstain from alcohol for the rest of his life, they said. But the couple, a Manhattan reporter and editor who asked to be identified only by their first names to protect their son’s privacy, resisted that approach. Instead, they turned to a group of psychologists who specialize in treating substance use and other compulsive behaviors at the Center for Motivation and Change. The center, known as the C.M.C., operates out of two floors of a 19th-century building on 30th Street and Fifth Avenue. It is part of a growing wing of addiction treatment that rejects the A.A. model of strict abstinence as the sole form of recovery for alcohol and drug users. Instead, it uses a suite of techniques that provide a hands-on, practical approach to solving emotional and behavioral problems, rather than having abusers forever swear off the substance — a particularly difficult step for young people to take. And unlike programs like Al-Anon, A.A.’s offshoot for family members, the C.M.C.’s approach does not advocate interventions or disengaging from someone who is drinking or using drugs. “The traditional language often sets parents up to feel they have to make extreme choices: Either force them into rehab or detach until they hit rock bottom,” said Carrie Wilkens, a psychologist who helped found the C.M.C. 10 years ago. “Science tells us those formulas don’t work very well.” When parents issue edicts, demanding an immediate end to all substance use, it often lodges the family in a harmful cycle, said Nicole Kosanke, a psychologist at the C.M.C. Tough love might look like an appropriate response, she said, but it often backfires by further damaging the frayed connections to the people to whom the child is closest. © 2014 The New York Times Company
Keyword: Drug Abuse
Link ID: 19794 - Posted: 07.04.2014
By Helen Briggs Health editor, BBC News website More than 99% of drug trials for Alzheimer's disease during the past decade have failed, according to a study. There is an urgent need to increase the number of potential therapies being investigated, say US scientists. Only one new medicine has been approved since 2004, they report in the journal Alzheimer's Research & Therapy. The drug failure rate is troubling and higher than for other diseases such as cancer, says Alzheimer's Research UK. Dr Jeffrey Cummings, of the Cleveland Clinic Lou Ruvo Center for Brain Health, in Las Vegas, and colleagues, examined a public website that records clinical trials. Between 2002 and 2012, they found 99.6% of trials of drugs aimed at preventing, curing or improving the symptoms of Alzheimer's had failed or been discontinued. This compares with a failure rate of 81% for cancer drugs. The failure rate was "especially troubling" given the rising numbers of people with dementia, said Dr Simon Ridley, of Alzheimer's Research UK. "The authors of the study highlight a worrying decline in the number of clinical trials for Alzheimer's treatments in more recent years," he said. "There is a danger that the high failure rates of trials in the past will discourage pharmaceutical companies from investing in dementia research. BBC © 2014
Link ID: 19793 - Posted: 07.04.2014
BY Jenny Marder and Rebecca Jacobson Scientists at the NIH are mapping the activity of thousands of individual neurons inside the brain of a zebrafish as the animal hunts for food. In a small, windowless room that houses two powerful electron microscopes, a scientist is searching for the perfect fish brain. As the massive machines hum nearby, two gigantic fish eyes loom large, taking up most of a computer screen. The magnified perspective is misleading. The zebrafish is a larva, a newborn, just one week old, and barely six millimeters long. On the screen, it looks grumpy, like it’s frowning. Chris Harris, a postdoctoral researcher at the lab, is scrolling through the image. As he zooms in, the eyes become even larger and then disappear altogether, replaced by a glimpse of what lies within and behind them in its brain: a jungle of axons and dendrites and cell bodies — all the stuff that makes up individual neurons. He traces the outer edge of one of the cells with a gloved finger. “This layer is the nuclear membrane,” he says. “And just outside of that is the cell body membrane itself.” He points out the mitochondria, the individual axons, which send nerve impulses from one neuron to the next; the branching dendrites, which receive signals; and thick black dots that represent synaptic vesicles — pouches that hold neurotransmitters, or brain chemicals. © 1996 - 2014 MacNeil / Lehrer Productions.
Keyword: Brain imaging
Link ID: 19792 - Posted: 07.04.2014
By LISA SANDERS, M.D. On Wednesday, we challenged Well readers to solve the case of a middle-aged woman who suddenly began to have episodes of confusion caused by low blood sugars. Her endocrinologist thought she might have an insulinoma, an insulin-producing tumor of the pancreas, but the testing he did seemed to rule out that diagnosis. Nearly 200 of you took on the challenge of trying to figure out what was causing her life-threatening drops in blood sugar level. The correct diagnosis is… Insulinoma The first respondent to make the diagnosis was Karen Unkel of Kinder, La. She is not a doctor but has a longstanding interest in hypoglycemia that allowed her to recognize the disease even in the face of an apparently negative work-up. Well done, Ms. Unkel. An insulinoma is a rare tumor of pancreatic tissue that makes and secretes insulin independently of blood glucose levels. This results in episodes of hypoglycemia that can be quite severe, even life-threatening. The diagnosis is suspected when a patient fulfills what is known as Whipple’s triad: 1) symptoms of hypoglycemia 2) associated with low measured blood sugar and 3) which improve when blood sugar is raised to the normal range. The diagnosis is made when doctors show that the patient is making too much insulin given his or her blood sugar level. Measuring insulin levels is not always accurate because insulin is processed rapidly in the body and because it is difficult to distinguish between insulin made naturally in the pancreas and any insulin that the patient might be injecting. What is measured instead is something known as C-peptide. Insulin is first made as a larger molecule known as proinsulin. When blood sugar rises, an extra bit is shaved off the molecule; that extra bit is C-peptide, and both the resulting insulin and C-peptide are released into the bloodstream. © 2014 The New York Times Company
—By Chris Mooney The United States has a voting problem. In the 2012 presidential election, only about 57 percent of eligible American voters turned out, a far lower participation rate than in comparable democracies. That means about 93 million people who were eligible to vote didn't bother. Clearly, figuring out why people vote (and why they don't) is of premium importance to those who care about the health of democracy, as well as to campaigns that are becoming ever more sophisticated in targeting individual voters. To that end, much research has shown that demographic factors such as age and poverty affect one's likelihood of voting. But are there individual-level biological factors that also influence whether a person votes? The idea has long been heretical in political science, and yet the logic behind it is unavoidable. People vary in all sorts of ways—ranging from personalities to genetics—that affect their behavior. Political participation can be an emotional, and even a stressful activity, and in an era of GOP-led efforts to make voting more difficult, voting in certain locales can be a major hassle. To vote, you need both to be motivated and also not so intimidated you stay away from the polls. So are there biological factors that can shape these perceptions? "Our study is unique in that it is the first to examine whether differences in physiology may be causally related to differences in political activity," says lead study author Jeffrey French. ©2014 Mother Jones
Link ID: 19790 - Posted: 07.04.2014
Hassan DuRant The colorful little guy pictured above puts the eyes of every other animal to shame. Whereas humans receive color information via three color receptors in our eyes, mantis shrimp (Neogonodactylus oerstedii) have 12. Six of these differentiate five discrete wavelengths of ultraviolet light, researchers report online today in Current Biology. The mantis shrimp’s vision is possible by making use of specially tuned, UV-specific optical filters in its color-detecting cone cells. The optical filters are made of mycosporine-like amino acids (MAAs), a substance commonly found in the skin or exoskeleton of marine organisms. Often referred to as nature’s sunscreens, MAAs are usually employed to protect an organism from DNA-damaging UV rays; however, the mantis shrimp has incorporated them into powerful spectral tuning filters. Though the reason for the mantis shrimp’s complex visual perception is poorly understood, one possibility is that the UV detection could help visualize otherwise difficult-to-see prey on coral reefs. Many organisms absorb UV light—these organisms would be easy to spot as black objects in a bright world. © 2014 American Association for the Advancement of Science
Link ID: 19789 - Posted: 07.04.2014
|By Ferris Jabr You know the exit is somewhere along this stretch of highway, but you have never taken it before and do not want to miss it. As you carefully scan the side of the road for the exit sign, numerous distractions intrude on your visual field: billboards, a snazzy convertible, a cell phone buzzing on the dashboard. How does your brain focus on the task at hand? To answer this question, neuroscientists generally study the way the brain strengthens its response to what you are looking for—jolting itself with an especially large electrical pulse when you see it. Another mental trick may be just as important, according to a study published in April in the Journal of Neuroscience: the brain deliberately weakens its reaction to everything else so that the target seems more important in comparison. Cognitive neuroscientists John Gaspar and John McDonald, both at Simon Fraser University in British Columbia, arrived at the conclusion after asking 48 college students to take attention tests on a computer. The volunteers had to quickly spot a lone yellow circle among an array of green circles without being distracted by an even more eye-catching red circle. All the while the researchers monitored electrical activity in the students' brains using a net of electrodes attached to their scalps. The recorded patterns revealed that their brains consistently suppressed reactions to all circles except the one they were looking for—the first direct evidence of this particular neural process in action. © 2014 Scientific American
Link ID: 19788 - Posted: 07.03.2014
by Helen Thomson ONE moment you're conscious, the next you're not. For the first time, researchers have switched off consciousness by electrically stimulating a single brain area. Scientists have been probing individual regions of the brain for over a century, exploring their function by zapping them with electricity and temporarily putting them out of action. Despite this, they have never been able to turn off consciousness – until now. Although only tested in one person, the discovery suggests that a single area – the claustrum – might be integral to combining disparate brain activity into a seamless package of thoughts, sensations and emotions. It takes us a step closer to answering a problem that has confounded scientists and philosophers for millennia – namely how our conscious awareness arises. Many theories abound but most agree that consciousness has to involve the integration of activity from several brain networks, allowing us to perceive our surroundings as one single unifying experience rather than isolated sensory perceptions. One proponent of this idea was Francis Crick, a pioneering neuroscientist who earlier in his career had identified the structure of DNA. Just days before he died in July 2004, Crick was working on a paper that suggested our consciousness needs something akin to an orchestra conductor to bind all of our different external and internal perceptions together. With his colleague Christof Koch, at the Allen Institute for Brain Science in Seattle, he hypothesised that this conductor would need to rapidly integrate information across distinct regions of the brain and bind together information arriving at different times. For example, information about the smell and colour of a rose, its name, and a memory of its relevance, can be bound into one conscious experience of being handed a rose on Valentine's day. © Copyright Reed Business Information Ltd.
Link ID: 19787 - Posted: 07.03.2014
Maggie Fox NBC News Walking is an almost magic elixir, doctors like to say. It can reverse diabetes, lower blood pressure, and help people keep the fat off. Now a study shows it can also help people with Parkinson’s disease. Parkinson’s patients who walked just three times a week felt less tired, less depressed and they found their Parkinson’s symptoms improved, also. “The results of our study suggest that walking may provide a safe and easily accessible way of improving the symptoms of Parkinson’s disease and improve quality of life,” Dr. Ergun Uc of the University of Iowa and the Veterans Affairs Medical Center of Iowa City, who led the study. The findings would only apply to Parkinson’s patients who can still walk easily. Parkinson’s is caused by the loss of brain cells that produce a message carrying-chemical, or neurotransmitter, that is important for movement. Symptoms can start with a barely noticeable trembling but worsen to difficulty walking and talking, depression and other disability. There’s no cure and the drugs used to treat the condition usually stop helping over time. Some people have trouble walking. But for those who don’t, the study found, walking can help their symptoms. And other research suggests that regular exercise can help slow down the progression of Parkinson’s. Various programs show that dancing,cycling, Pilates and even boxing can help. But walking has a big advantage – people can do it anywhere, without special equipment, and on their own schedules.
Link ID: 19786 - Posted: 07.03.2014
By Smitha Mundasad Health reporter, BBC News Researchers have identified a gene that may put people at greater risk of strokes and heart attacks. Writing in PLOS ONE they say the gene fault may encourage the formation of blood clots - the ultimate cause of most heart attacks and strokes. Scientists hope gene tests may help doctors one day to pinpoint individuals more likely to suffer these conditions. But experts say lifestyle factors such as smoking and exercise have the greatest influence on risk. Around one in 10 people in the Caucasian population carries this variation of the gene, named PIA2. And researchers from King's College London reviewed more than 80 studies involving about 50,000 people - the largest analysis of this genetic fault to date. Threat to under-45s They found individuals with PIA2 were more likely to have a stroke - caused by a blood clot blocking blood supply to the brain - than those without the gene. Scientists calculate the gene increases a person's risk of having a stroke by 10-15%. But how significant this increase is depends on an individual's baseline risk - influenced by factors such as smoking, diet, weight and exercise, the scientists say. Heart attacks are caused by a blockage to the blood vessels that carry oxygen to the heart. More than 100,000 heart attacks are recorded in the UK each year And for people with two copies of the gene the risk rises by up to 70% from this baseline. In a second study published in the same journal, the scientists show PIA2 is also linked to an increased risk of heart attacks in people under 45. More research is needed to see whether this holds true for the whole population, they say. About 150,000 people have a stroke in the UK each year and more than 100,000 heart attacks are recorded annually. BBC © 2014
From David Beckham’s infamous kick at France '98 to Luis Suárez chomping Giorgio Chiellini's shoulder in Brazil last week, the history of the World Cup is littered with moments of impulsive aggression that appear to defy all rational explanation. The story of human impulsivity stretches back deep into our evolutionary past. By nature, we are all prone to making quick, rash decisions that may lead to regret, and in some cases a four-month ban from international football. Impulsivity is actually a survival mechanism and was essential in the African savanna where our species evolved around a million and a half years ago. For our ancestors, the ability to make split-second decisions could make the difference between life and death. All of us have deep primal instincts but over the several hundred million years of evolution separating our reptilian ancestors from the first mammals, and eventually primates, the cognitive ability to exercise self-restraint has increased. While most living things make this decision purely as a trade-off between risk and reward, only humans can decide to exercise self-restraint on the basis of how they think they will be perceived by others – an ability that emerged some time in the past 100,000 years or so. “We evolved to be very social animals, living in large groups, and so we have developed inhibitory mechanisms in the more recently evolved parts of the prefrontal cortex,” explains Michael Price of the School of Social Sciences at the University of Brunel. “This is the social centre of the brain. Our big reason not to be impulsive is because of your reputation and how other people are going to judge you and perhaps ostracise you as we saw with Beckham in the aftermath of France ’98.” © 2014 Guardian News and Media Limited
By GRETCHEN REYNOLDS Exercise may help to keep the brain robust in people who have an increased risk of developing Alzheimer’s disease, according to an inspiring new study. The findings suggests that even moderate amounts of physical activity may help to slow the progression of one of the most dreaded diseases of aging. For the new study, which was published in May in Frontiers in Aging Neuroscience, researchers at the Cleveland Clinic in Ohio recruited almost 100 older men and women, aged 65 to 89, many of whom had a family history of Alzheimer’s disease. Alzheimer’s disease, characterized by a gradual and then quickening loss of memory and cognitive functioning, can strike anyone. But scientists have discovered in recent years that people who harbor a specific variant of a gene, known as the APOE epsilon4 allele or the e4 gene for short, have a substantially increased risk of developing the disease. Genetic testing among the volunteers in the new study determined that about half of the group carried the e4 gene, although, at the start of the study, none showed signs of memory loss beyond what would be normal for their age. Then the scientists set out to more closely examine their volunteers’ brains. For some time, researchers have suspected that Alzheimer’s disease begins altering the structure and function of the brain years or even decades before the first symptoms appear. In particular, it’s been thought that the disease silently accelerates the atrophy of the hippocampus, a portion of the brain critical for memory processing. Brain scans of people who have Alzheimer’s show that their hippocampi are considerably more shrunken than those of people of the same age without the disease. There’s been less study, though, of possible shrinkage in the brains of cognitively normal people at risk for Alzheimer’s. One reason is that, until recently, few interventions, including drugs, had shown much promise in slowing or preventing the disease’s progression, so researchers – and patients – have been reluctant to identify markers of its potential onset. © 2014 The New York Times Company
Link ID: 19783 - Posted: 07.02.2014
Claire McCarthy I have many patients with ADHD (Attention Deficit Hyperactivity Disorder) and it seems like I have the same conversation over and over again with their parents: to medicate or not to medicate. I completely understand the hesitation I hear from so many parents. I have to admit, I'm not entirely happy myself about prescribing a medication that has side effects and can be abused or misused, and one for which there is a black market. I also worry that too often when a child is on medication and so learning and behaving better, parents and teachers lose the incentive to help the child learn the organizational and other skills that could make all the difference later in life. Since ADHD often persists into adulthood, we have to have the long view with these kids. But....the long view works the other way, too. Not treating ADHD with medication can lead to problems. Like drug abuse. ADHD is really common. It affects 8 percent of children and youth--that's about 2 in every classroom of 20. Kids with ADHD can have real problems with both learning and behavior, problems that can haunt them for a lifetime (if you end up dropping out of high school because of poor grades or behavior, or end up getting arrested, it has a way of interfering with your future income and quality of life). But another thing we know is that kids with ADHD have a higher risk of drug abuse. We don't know exactly why this is the case. Some of it is likely the impulsivity that is so common in people with ADHD; they don't always make the best decisions. It may also be that people with ADHD are more prone to addiction. Whatever it is, the risk is very real. Not only are kids with ADHD 2.5 times more likely to abuse drugs, they are more likely to start earlier, use more types of drugs, and continue into adulthood. ©2014 Boston Globe Media Partners, LLC
Learning a second language benefits the brain in ways that can pay off later in life, suggests a deepening field of research that specializes in the relationship between bilingualism and cognition. In one large Scottish test, researchers discovered archival data on 835 native speakers of English who were born in Edinburgh in 1936. The participants had been given an intelligence test at age 11 as part of standard British educational policy and many were retested in their early 70s. Those who spoke two or more languages had significantly better cognitive abilities on certain tasks compared with what would be expected from their IQ test scores at age 11, Dr. Thomas Bak of the Centre for Cognitive Aging and Cognitive Epidemiology at the University of Edinburgh reported in the journal Annals of Neurology. "Our results suggest a protective effect of bilingualism against age-related cognitive decline," independently of IQ, Bak and his co-authors concluded. It was a watershed study in 1962 by Elizabeth Peal and Wallace Lambert at McGill University in Montreal that turned conventional thinking on bilingualism on its head and set the rationale for French immersion in Canada. Psychologists at York University in Toronto have also been studying the effect of bilingualism on the brain across the lifespan, including dementia. They’ve learned how people who speak a second language outperform those with just one on tasks that tap executive function such as attention, selection and inhibition. Those are the high-level cognitive processes we use to multitask as we drive on the highway and juggle remembering the exit and monitoring our speed without getting distracted by billboards. © CBC 2014
by Laura Sanders At the playground yesterday, Baby V commando-crawled through a tunnel with holes on the side. Every so often, I stuck my face in there with a loud “peekaboo.” She reached up longingly toward the bouncy duck. I picked her up and steadied her as she lurched back and forth. She scrambled up some low stairs and launched down a slide. I lurked near the bottom, ready to assist and yell “yay” when she didn’t face-plant. The one thing I didn’t do was sit back and leave her to her own devices, free from my helicopter-mom tendencies. But since I have the most ridiculous crush on that girl, it’s hard for me to leave her be. As a parent who works outside of the home, I treasure our time together. But as she becomes more capable and independent, I realize that I need to be more thoughtful about letting her carve out some space for herself. A recent research paper emphasized this point. The study, published June 17 in Frontiers in Psychology, finds that children who spend more time in unstructured activities may better master some important life skills. Researchers sorted kids’ activities into structured activities, which included child-initiated activities such as playing alone or with friends, singing, riding bikes and camping, and structured activities, including soccer practice, piano lessons, chores and homework. Six- and seven-year-olds who had more unstructured time scored higher on a measure of executive function, complex cognitive abilities such as seamlessly switching between tasks, resisting impulses and paying attention — all things that help people get along in this world. © Society for Science & the Public 2000 - 2013.
Keyword: Development of the Brain
Link ID: 19780 - Posted: 07.02.2014
Simon Makin Running helps mice to recover from a type of blindness caused by sensory deprivation early in life, researchers report. The study, published on 26 June in eLife1, also illuminates processes underlying the brain’s ability to rewire itself in response to experience — a phenomenon known as plasticity, which neuroscientists believe is the basis of learning. More than 50 years ago, neurophysiologists David Hubel and Torsten Wiesel cracked the 'code' used to send information from the eyes to the brain. They also showed that the visual cortex develops properly only if it receives input from both eyes early in life. If one eye is deprived of sight during this ‘critical period’, the result is amblyopia, or ‘lazy eye’, a state of near blindness. This can happen to someone born with a droopy eyelid, cataract or other defect not corrected in time. If the eye is opened in adulthood, recovery can be slow and incomplete. In 2010, neuroscientists Christopher Niell and Michael Stryker, both at the University of California, San Francisco (UCSF), showed that running more than doubled the response of mice's visual cortex neurons to visual stimulation2 (see 'Neuroscience: Through the eyes of a mouse'). Stryker says that it is probably more important, and taxing, to keep track of the environment when navigating it at speed, and that lower responsiveness at rest may have evolved to conserve energy in less-demanding situations. “It makes sense to put the visual system in a high-gain state when you’re moving through the environment, because vision tells you about far away things, whereas touch only tells you about things that are close,” he says. © 2014 Nature Publishing Group
James Gorman All moving animals do their best to avoid running into things. And most living things follow a tried and true strategy — Watch where you’re going! Flying and swimming animals both have to cope with some complications that walkers, jumpers and gallopers don’t confront. Not only do they have to navigate in three dimensions, but they also cope with varying air and water flow. Beyond that, they often do so without the same references points and landmarks we have on the ground. Christine Scholtyssek of Lund University in Sweden, and colleagues decided to compare how two species in different mediums, air and water, which pose similar problems, reacted to apparent obstacles as they were moving. What they found, and reported in Biology Letters in May, was that the two species they examined — bumblebees and zebra fish — have very different strategies. It was known that the bees’ navigation depended on optic flow, which is something like the sensation of watching telephone poles speed past from a seat on a moving train. They tend to fly away from apparent obstacles as they approach them. The question was whether fish would do something similar. So, in order to give both animals the same test, Dr. Scholtyssek and her colleagues devised an apparatus that could contain air or water. When one wall had vertical stripes and the other horizontal, the bees, not surprisingly, flew away from the vertical stripes, which would have appeared as one emerging obstacle after another as the bees flew past. Horizontal stripes don’t change as a creature moves past, so they provide no reference for speed or progress. The fish, however, swam closer to the vertical stripes, which wasn’t expected. “It is surprising that although fish and bees have the same challenge, moving with or against streams, they do not use the same mechanisms,” Dr. Scholtyssek said. © 2014 The New York Times Company
Keyword: Animal Migration
Link ID: 19778 - Posted: 07.01.2014
By Lori Aratani The placebo effect — the idea that a treatment works because a patient believes it does — has long been a footnote to the work of finding ways to counteract disease. Some physicians have dismissed placebos as mere hokum, a trick of the mind. But researchers have found that in some people, placebos elicit similar responses in the brain to actual drug treatments. In one experiment, researchers using a PET scanner found that the brain activity in test subjects who received placebos and reported less pain mirrored that of those who received actual treatment for their pain. As Erik Vance writes in “Why Nothing Works,” published in the July/August 2014 issue of Discover magazine, the work suggests we possess an “inner pharmacy” of some sort that, if harnessed correctly, could be used as a complement to traditional treatments. But as Vance’s overview of recent research on the topic shows, it’s complicated. A placebo’s impact is not universal. Certain individuals — and certain conditions (pain and depression, for example) — seem to respond better than others to placebos. Researchers think that something in a person’s physiological makeup makes him more sensitive to placebos, while others feel little or no impact. There are ethical considerations, too, since it’s considered wrong to mislead volunteers participating in a study. But there are ways to navigate this thicket. In one small study, researchers gave placebos to a group of people with irritable bowel syndrome — after telling them that the pills were just placebos; a second group received no treatment. Surprisingly, many more of those who received the placebos reported improvements in their symptoms than did people in the no-treatment group.