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Amanda Aronczyk At first Giselle wasn't sure what to put on her medical school application. She wanted to be a doctor, but she also wanted people to know about her own health: years of depression, anxiety and a suicide attempt. (We're using only her first name in this story, out of concern for her future career.) "A lot of people were like, you don't say that at all," she said. "Do not mention that you have any kind of weakness." Giselle remembers having her first intense suicidal thoughts when she was 10 years old. Her parents had split up and she had moved from the coast of Colombia to Chicago. She started having extreme mood swings and fighting with her mom. And then, when she was 16 years old, she tried to kill herself. "Yeah, lots of pills." After her suicide attempt she began therapy and eventually started taking antidepressants. That worked extremely well. After finishing high school, she took an unconventional route. She went to Brazil to work with a women's community health group, worked as a research assistant for a doctor, and trained as a doula to assist women in labor. It was while working as a doula and witnessing what she saw as insensitive behavior from a doctor that she resolved her own career indecision: She would become a different kind of doctor. When she applied to medical school, she told them this whole story in her application. In the fall of 2014, she started at the University of Wisconsin School of Medicine and Public Health. © 2016 npr
Link ID: 22276 - Posted: 06.02.2016
By Ann Griswold, Women who develop infections during pregnancy run an increased risk of having a child with autism. Most data indicate that an overactive maternal immune response underlies the risk. But a new analysis runs contrary to this view: It ties high levels of an inflammatory protein in pregnant women to a low risk of autism in their children, suggesting that a strong immune response is protective. Researchers looked at 1,315 mother-child pairs, including 500 children with autism and 235 with developmental delay. They found that healthy pregnant women with high levels of C-reactive protein (CRP), a marker of inflammation, are less likely to have a child with autism than are women with typical levels of the protein. The findings contradict a 2013 report from a large Finnish cohort that tied high CRP levels during pregnancy to an increased risk of having a child with autism. “It was the opposite of what we expected to find,” says senior researcher Lisa Croen, director of the Autism Research Program at Kaiser Permanente in Oakland, California. The work appeared in April in Translational Psychiatry. The results suggest that the strength of a woman’s immune system, rather than its response to infection, is the important factor in determining autism risk. Moderate or low baseline levels of CRP might indicate a relatively weak ability to fight off infection. And a less vigorous immune response might boost the risk in some women, the researchers say. © 2016 Scientific American,
By Mark Gollom, Anti-smoking advocates who support the Liberal government's proposal to require plain packaging on tobacco products argue that Australia's implementation of similar regulations has had a significant effect on smoking rates in that country. "Australia has seen the biggest decline in smoking prevalence that they've ever recorded after plain packing [was introduced]," said David Hammond, an associate professor of public health and health systems at the University of Waterloo. "All the data we have suggest that plain packing has reduced smoking in Australia." Rob Cunningham, senior policy analyst for the Canadian Cancer Society, agrees and says research supports the effectiveness of plain packaging. "If it wasn't effective, the tobacco companies wouldn't be so strongly opposed," he said. "And it's precisely because it's going to have an effect on sales that they are going to lobby hard against it, threaten legal cases." But not everyone believes that Australia's policy of imposing bland tobacco branding has done much to deter smoking, which has been steadily declining for decades, according to Julian Morris, vice-president of research at the libertarian think tank the Reason Foundation. "The decline in smoking seems to have been continuous and not dramatically effected, one way or the other, by the introduction of plain packaging," he said. ©2016 CBC/Radio-Canada.
Keyword: Drug Abuse
Link ID: 22274 - Posted: 06.02.2016
By Ann Lukits Teens who baby-sit may not only gain confidence in caring for young children, they may also alter their brain chemistry in a way that could make them better parents, suggests an animal study in Developmental Psychobiology. Young female rats housed with various groups of unrelated rat pups had fully developed mothering skills as adults, compared with control rats without caregiving, or alloparenting, experience. The early caregivers had significantly higher concentrations of tryptophan hydroxylase-2 (TPH2) in the brain, an enzyme associated with increased production of serotonin, a chemical involved in mood and social behavior. Previous research has associated baby-sitting experience in humans with greater confidence in new mothers, researchers said. Experiments at Michigan State University involved two groups of juvenile or adolescent female rats from 16 litters. In one group, 24 rats were housed in separate cages with a different group of week-old pups each day. A second group of 24 controls were given pink pup-size pencil erasers. The experiments continued for 14 days. Eight mature rats from both groups were subsequently exposed to new groups of pups. Six rats with alloparenting experience acted maternally toward the pups, whereas none of the control rats exhibited maternal behavior. Rats with alloparenting experience also displayed less anxiety during behavioral testing. The animals were euthanized after testing and TPH2 levels measured in a section of the brain called the dorsal raphe nucleus. ©2016 Dow Jones & Company, Inc
Keyword: Sexual Behavior
Link ID: 22273 - Posted: 06.01.2016
By David Z. Hambrick If you’re a true dog lover, you take it as one of life’s simple truths that all dogs are good, and you have no patience for scientific debate over whether dogs really love people. Of course they do. What else could explain the fact that your dog runs wildly in circles when you get home from work, and, as your neighbors report, howls inconsolably for hours on end when you leave? What else could explain the fact that your dog insists on sleeping in your bed, under the covers—in between you and your partner? At the same time, there’s no denying that some dogs are smarter than others. Not all dogs can, like a border collie mix named Jumpy, do a back flip, ride a skateboard, and weave through pylons on his front legs. A study published in the journal Intelligence by British psychologists Rosalind Arden and Mark Adams confirms as much. Consistent with over a century of research on human intelligence, Arden and Adams found that a dog that excels in one test of cognitive ability will likely excel in other tests of cognitive ability. In more technical terms, the study reveals that there is a general factor of intelligence in dogs—a canine “g” factor. For their study, Arden and Adams devised a battery of canine cognitive ability tests. All of the tests revolved around—you guessed it—getting a treat. In the detour test, the dog’s objective was to navigate around barriers arranged in different configurations to get to a treat. In the point-following test, a researcher pointed to one of two inverted beakers concealing a treat, and recorded whether the dog went to that beaker or the other one. Finally, the quantity discrimination test required the dog to choose between a small treat (a glob of peanut butter) and a larger one (the “correct” answer). Arden and Adams administered the battery to 68 border collies from Wales; all had been bred and trained to do herding work on a farm, and thus had similar backgrounds. © 2016 Scientific American
By Frances Marcellin A shirt and cap that can diagnose epilepsy quickly and easily has been approved for use by European health services, including the UK’s NHS. Epileptic seizures are the result of excessive electrical discharges in the brain. The World Health Organization estimates that over 50 million people worldwide have the condition, including 6 million in Europe, making it one of the world’s most common serious neurological conditions. Brain implants and apps have been developed to warn of oncoming seizures. But to diagnose the condition, someone must typically have a seizure recorded by an EEG machine in a hospital – with sensors and wires attached to the scalp. “An EEG reading is at the heart of a reliable diagnosis,” says Françoise Thomas-Vialettes, president of French epilepsy society EFAPPE. But seizures rarely coincide with hospital appointments. “The diagnosis can take several years and is often imprecise.” Seizures are so difficult to record that 30 per cent of people with epilepsy in Europe are misdiagnosed. In developing countries that lack medical equipment and healthcare the situation is even worse. To make diagnosis easier, French start-up BioSerenity has developed a smart outfit called the Neuronaute that monitors people as they go about their day. The shirt and cap are embedded with biometric sensors that record the electrical activity of the wearer’s brain, heart and muscles. If a seizure occurs, the outfit can send an EEG recording of the brain to doctors via a smartphone. © Copyright Reed Business Information Ltd.
Link ID: 22271 - Posted: 06.01.2016
By Gretchen Reynolds A weekly routine of yoga and meditation may strengthen thinking skills and help to stave off aging-related mental decline, according to a new study of older adults with early signs of memory problems. Most of us past the age of 40 are aware that our minds and, in particular, memories begin to sputter as the years pass. Familiar names and words no longer spring readily to mind, and car keys acquire the power to teleport into jacket pockets where we could not possibly have left them. Some weakening in mental function appears to be inevitable as we age. But emerging science suggests that we might be able to slow and mitigate the decline by how we live and, in particular, whether and how we move our bodies. Past studies have found that people who run, weight train, dance, practice tai chi, or regularly garden have a lower risk of developing dementia than people who are not physically active at all. There also is growing evidence that combining physical activity with meditation might intensify the benefits of both pursuits. In an interesting study that I wrote about recently, for example, people with depression who meditated before they went for a run showed greater improvements in their mood than people who did either of those activities alone. But many people do not have the physical capacity or taste for running or other similarly vigorous activities. So for the new study, which was published in April in the Journal of Alzheimer’s Disease, researchers at the University of California, Los Angeles, and other institutions decided to test whether yoga, a relatively mild, meditative activity, could alter people’s brains and fortify their ability to think. © 2016 The New York Times Company
Keyword: Learning & Memory
Link ID: 22270 - Posted: 06.01.2016
Amy McDermott Giant pandas have better ears than people — and polar bears. Pandas can hear surprisingly high frequencies, conservation biologist Megan Owen of the San Diego Zoo and colleagues report in the April Global Ecology and Conservation. The scientists played a range of tones for five zoo pandas trained to nose a target in response to sound. Training, which took three to six months for each animal, demanded serious focus and patience, says Owen, who called the effort “a lot to ask of a bear.” Both males and females heard into the range of a “silent” ultrasonic dog whistle. Polar bears, the only other bears scientists have tested, are less sensitive to sounds at or above 14 kilohertz. Researchers still don’t know why pandas have ultrasonic hearing. The bears are a vocal bunch, but their chirps and other calls have never been recorded at ultrasonic levels, Owen says. Great hearing may be a holdover from the bears’ ancient past. Citations M.A. Owen et al. Hearing sensitivity in context: Conservation implications for a highly vocal endangered species. Global Ecology and Conservation. Vol. 6, April 2016, p. 121. doi: 10.1016/j.gecco.2016.02.007. © Society for Science & the Public 2000 - 2016.
Link ID: 22269 - Posted: 06.01.2016
By Kelly Servick There’s an unfortunate irony for people who rely on morphine, oxycodone, and other opioid painkillers: The drug that’s supposed to offer you relief can actually make you more sensitive to pain over time. That effect, known as hyperalgesia, could render these medications gradually less effective for chronic pain, leading people to rely on higher and higher doses. A new study in rats—the first to look at the interaction between opioids and nerve injury for months after the pain-killing treatment was stopped—paints an especially grim picture. An opioid sets off a chain of immune signals in the spinal cord that amplifies pain rather than dulling it, even after the drug leaves the body, the researchers found. Yet drugs already under development might be able to reverse the effect. It’s no secret that powerful painkillers have a dark side. Overdose deaths from prescription opioids have roughly quadrupled over 2 decades, in near lockstep with increased prescribing. And many researchers see hyperalgesia as a part of that equation—a force that compels people to take more and more medication, while prolonging exposure to sometimes addictive drugs known to dangerously slow breathing at high doses. Separate from their pain-blocking interaction with receptors in the brain, opioids seem to reshape the nervous system to amplify pain signals, even after the original illness or injury subsides. Animals given opioids become more sensitive to pain, and people already taking opioids before a surgery tend to report more pain afterward. © 2016 American Association for the Advancement of Scienc
By Gary Stix Scientists will never find a single gene for depression—nor two, nor 20. But among the 20,000 human genes and the hundreds of thousands of proteins and molecules that switch on those genes or regulate their activity in some way, there are clues that point to the roots of depression. Tools to identify biological pathways that are instrumental in either inducing depression or protecting against it have recently debuted—and hold the promise of providing leads for new drug therapies for psychiatric and neurological diseases. A recent paper in the journal Neuron illustrates both the dazzling complexity of this approach and the ability of these techniques to pinpoint key genes that may play a role in governing depression. Scientific American talked with the senior author on the paper—neuroscientist Eric Nestler from the Icahn School of Medicine at Mt. Sinai in New York. Nestler spoke about the potential of this research to break the logjam in pharmaceutical research that has impeded development of drugs to treat brain disorders. Scientific American: The first years in the war on cancer met with a tremendous amount of frustration. Things look like they're improving somewhat now for cancer. Do you anticipate a similar trajectory may occur in neuroscience for psychiatric disorders? Eric Nestler: I do. I just think it will take longer. I was in medical school 35 years ago when the idea that identifying a person's specific pathophysiology was put forward as a means of directing treatment of cancer. We're now three decades later finally seeing the day when that’s happening. I definitely think the same will occur for major brain disorders. The brain is just more complicated and the disorders are more complicated so it will take longer. © 2016 Scientific American
What do large tables, large breakfasts, and large servers have in common? They all affect how much you eat. This week on Hidden Brain, we look at the hidden forces that drive our diets. First we hear from Adam Brumberg at Cornell University's Food and Brand Lab about how to make healthier choices more easily (hint: good habits and pack your lunch!). Then, Senior (Svelte) Stopwatch Correspondent Daniel Pink returns for another round of Stopwatch Science to tell you about those tables, breakfasts, and servers. If you don't like spoilers, stop reading and go listen to the episode! Here are the studies: You may have heard that smaller portions can help you eat fewer calories. That's true. But what about larger tables? Researchers Brennan Davis, Collin Payne, and My Bui hypothesized that one of the ways smaller food units lead us to eat less is by playing with our perception. They tested this with pizza and found that while study participants tended to eat more small slices, they consumed fewer calories overall because it seemed like they were eating more. The researchers tried to distort people's perception even further by making the smaller slices seem bigger by putting them on a bigger table. What they found is that even hungry college students at fewer calories of (free) pizza when it was chopped into tiny slices and put on a big table. What about who's around that big table? That seems to matter, too. Researchers found both men and women order more food when they eat with women but choose smaller portions when they eat in the company of men. They say breakfast is the most important meal of the day. Well, it may also be the most slimming. When researchers assigned two groups of overweight women to eat a limited number of calories each day, they found those who ate more at breakfast and less at dinner shed about twice as many pounds as the other group. © 2016 npr
Link ID: 22266 - Posted: 05.31.2016
By Anil Ananthaswamy and Alice Klein Our brain’s defence against invading microbes could cause Alzheimer’s disease – which suggests that vaccination could prevent the condition. Alzheimer’s disease has long been linked to the accumulation of sticky plaques of beta-amyloid proteins in the brain, but the function of plaques has remained unclear. “Does it play a role in the brain, or is it just garbage that accumulates,” asks Rudolph Tanzi of Harvard Medical School. Now he has shown that these plaques could be defences for trapping invading pathogens. Working with Robert Moir at the Massachusetts General Hospital in Boston, Tanzi’s team has shown that beta-amyloid can act as an anti-microbial compound, and may form part of our immune system. .. To test whether beta-amyloid defends us against microbes that manage to get into the brain, the team injected bacteria into the brains of mice that had been bred to develop plaques like humans do. Plaques formed straight away. “When you look in the plaques, each one had a single bacterium in it,” says Tanzi. “A single bacterium can induce an entire plaque overnight.” Double-edged sword This suggests that infections could be triggering the formation of plaques. These sticky plaques may trap and kill bacteria, viruses or other pathogens, but if they aren’t cleared away fast enough, they may lead to inflammation and tangles of another protein, called tau, causing neurons to die and the progression towards © Copyright Reed Business Information Ltd.
Robert Plomin, Scientists have investigated this question for more than a century, and the answer is clear: the differences between people on intelligence tests are substantially the result of genetic differences. But let's unpack that sentence. We are talking about average differences among people and not about individuals. Any one person's intelligence might be blown off course from its genetic potential by, for example, an illness in childhood. By genetic, we mean differences passed from one generation to the next via DNA. But we all share 99.5 percent of our three billion DNA base pairs, so only 15 million DNA differences separate us genetically. And we should note that intelligence tests include diverse examinations of cognitive ability and skills learned in school. Intelligence, more appropriately called general cognitive ability, reflects someone's performance across a broad range of varying tests. Genes make a substantial difference, but they are not the whole story. They account for about half of all differences in intelligence among people, so half is not caused by genetic differences, which provides strong support for the importance of environmental factors. This estimate of 50 percent reflects the results of twin, adoption and DNA studies. From them, we know, for example, that later in life, children adopted away from their biological parents at birth are just as similar to their biological parents as are children reared by their biological parents. Similarly, we know that adoptive parents and their adopted children do not typically resemble one another in intelligence. © 2016 Scientific American
By Viviane Callier Bees don’t just recognize flowers by their color and scent; they can also pick up on their minute electric fields. Such fields—which form from the imbalance of charge between the ground and the atmosphere—are unique to each species, based on the plant’s distance from the ground and shape. Flowers use them as an additional way to advertise themselves to pollinators, but until now researchers had no idea how bees sensed these fields. In a new study, published online today in the Proceedings of the National Academy of Sciences, researchers used a laser vibrometer—a tiny machine that hits the bee hair with a laser—to measure how the hair on a bee’s body responds to a flower’s tiny electric field. As the hair moves because of the electric field, it changes the frequency of the laser light that hits it, allowing the vibrometer to keep track of the velocity of motion of the hair. When the bees buzzed within 10 centimeters of the flower, the electric field—like static electricity from a balloon—caused the bee’s hair to bend. This bending activates neurons at the base of bee hair sockets, which allows the insects to “sense” the field, the team found. Electric fields can only be sensed from a distance of 10 cm or so, so they’re not very useful for large animals like ourselves. But for small insects, this distance represents several body lengths, a relatively long distance. Because sensing such fields is useful to small animals, the team suspects this ability could be important to other insect species as well. © 2016 American Association for the Advancement of Science.
Keyword: Pain & Touch
Link ID: 22263 - Posted: 05.31.2016
By Jane E. Brody Joanne Reitano is a professor of history at LaGuardia Community College in Long Island City, Queens. She writes wonderful books about the history of the city and state, and has recently been spending many hours — sometimes all day — at her computer to revise her first book, “The Restless City.” But while sitting in front of the screen, she told me, “I developed burning in my eyes that made it very difficult to work.” After resting her eyes for a while, the discomfort abates, but it quickly returns when she goes back to the computer. “If I was playing computer games, I’d turn off the computer, but I need it to work,” the frustrated professor said. Dr. Reitano has a condition called computer vision syndrome. She is hardly alone. It can affect anyone who spends three or more hours a day in front of computer monitors, and the population at risk is potentially huge. Worldwide, up to 70 million workers are at risk for computer vision syndrome, and those numbers are only likely to grow. In a report about the condition written by eye care specialists in Nigeria and Botswana and published in Medical Practice and Reviews, the authors detail an expanding list of professionals at risk — accountants, architects, bankers, engineers, flight controllers, graphic artists, journalists, academicians, secretaries and students — all of whom “cannot work without the help of computer.” And that’s not counting the millions of children and adolescents who spend many hours a day playing computer games. Studies have indicated 70 percent to 90 percent of people who use computers extensively, whether for work or play, have one or more symptoms of computer vision syndrome. The effects of prolonged computer use are not just vision-related. Complaints include neurological symptoms like chronic headaches and musculoskeletal problems like neck and back pain. © 2016 The New York Times Company
Link ID: 22262 - Posted: 05.30.2016
By C. CLAIBORNE RAY Q. Does the size of an animal’s brain really correlate with intelligence on a species-by-species basis? A. “It’s not necessarily brain size but rather the ratio of brain size to body size that really tells the story,” said Rob DeSalle, a curator at the Sackler Institute for Comparative Genomics at the American Museum of Natural History. Looking at this ratio over a large number of vertebrate animals, he said, scientists have found that “brain size increases pretty linearly with body size, except for some critical species like Homo sapiens and some cetaceans,” the order of mammals that includes whales, dolphins and porpoises. “So if there is a deviation from this general ratio, one can predict how smart a vertebrate might be,” Dr. DeSalle continued. Therefore, living vertebrates that deviate so that their brains are inordinately bigger compared with their bodies are for the most part smarter, he said. As for dinosaurs, he said, scientists really can’t tell how smart they may have been. “But the Sarmientosaurus, with its lime-sized brain, was a big animal, so the extrapolation is that it would have been pretty dense,” he said. “On the other hand, Troodon, a human-sized dinosaur, had a huge brain relative to its body size and is widely considered the smartest dinosaur ever found.” © 2016 The New York Times Company
Link ID: 22261 - Posted: 05.30.2016
By David Shultz We still may not know what causes consciousness in humans, but scientists are at least learning how to detect its presence. A new application of a common clinical test, the positron emission tomography (PET) scan, seems to be able to differentiate between minimally conscious brains and those in a vegetative state. The work could help doctors figure out which brain trauma patients are the most likely to recover—and even shed light on the nature of consciousness. “This is really cool what these guys did here,” says neuroscientist Nicholas Schiff at Cornell University, who was not involved in the study. “We’re going to make great use of it.” PET scans work by introducing a small amount of radionuclides into the body. These radioactive compounds act as a tracer and naturally emit subatomic particles called positrons over time, and the gamma rays indirectly produced by this process can be detected by imaging equipment. The most common PET scan uses fluorodeoxyglucose (FDG) as the tracer in order to show how glucose concentrations change in tissue over time—a proxy for metabolic activity. Compared with other imaging techniques, PET scans are relatively cheap and easy to perform, and are routinely used to survey for cancer, heart problems, and other diseases. In the new study, researchers used FDG-PET scans to analyze the resting cerebral metabolic rate—the amount of energy being used by the tissue—of 131 patients with a so-called disorder of consciousness and 28 healthy controls. Disorders of consciousness can refer to a wide range of problems, ranging from a full-blown coma to a minimally conscious state in which patients may experience brief periods where they can communicate and follow instructions. Between these two extremes, patients may be said to be in a vegetative state or exhibit unresponsive wakefulness, characterized by open eyes and basic reflexes, but no signs of awareness. Most disorders of consciousness result from head trauma, and where someone falls on the consciousness continuum is typically determined by the severity of the injury. © 2016 American Association for the Advancement of Science
By Roland Pease BBC Radio Science Unit Researchers have invented a DNA "tape recorder" that can trace the family history of every cell in an organism. The technique is being hailed as a breakthrough in understanding how the trillions of complex cells in a body are descended from a single egg. "It has the potential to provide profound insights into how normal, diseased or damaged tissues are constructed and maintained," one UK biologist told the BBC. The work appears in Science journal. The human body has around 40 trillion cells, each with a highly specialised function. Yet each can trace its history back to the same starting point - a fertilised egg. Developmental biology is the business of unravelling how the genetic code unfolds at each cycle of cell division, how the body plan develops, and how tissues become specialised. But much of what it has revealed has depended on inference rather than a complete cell-by-cell history. "I actually started working on this problem as a graduate student in 2000," confessed Jay Shendure, lead researcher on the new scientific paper. "Could we find a way to record these relationships between cells in some compact form we could later read out in adult organisms?" The project failed then because there was no mechanism to record events in a cell's history. That changed with recent developments in so called CRISPR gene editing, a technique that allows researchers to make much more precise alterations to the DNA in living organisms. The molecular tape recorder developed by Prof Shendure's team at the University of Washington in Seattle, US, is a length of DNA inserted into the genome that contains a series of edit points which can be changed throughout an organism's life. © 2016 BBC.
By BENEDICT CAREY Suzanne Corkin, whose painstaking work with a famous amnesiac known as H.M. helped clarify the biology of memory and its disorders, died on Tuesday in Danvers, Mass. She was 79. Her daughter, Jocelyn Corkin, said the cause was liver cancer. Dr. Corkin met the man who would become a lifelong subject and collaborator in 1964, when she was a graduate student in Montreal at the McGill University laboratory of the neuroscientist Brenda Milner. Henry Molaison — known in published reports as H.M., to protect his privacy — was a modest, middle-aged former motor repairman who had lost the ability to form new memories after having two slivers of his brain removed to treat severe seizures when he was 27. In a series of experiments, Dr. Milner had shown that a part of the brain called the hippocampus was critical to the consolidation of long-term memories. Most scientists had previously thought that memory was not dependent on any one cortical area. Mr. Molaison lived in Hartford, and Dr. Milner had to take the train down to Boston and drive from there to Connecticut to see him. It was a long trip, and transporting him to Montreal proved to be so complicated, largely because of his condition, that Dr. Milner did it just once. Yet rigorous study of H.M., she knew, would require proximity and a devoted facility — with hospital beds — to accommodate extended experiments. The psychology department at the Massachusetts Institute of Technology offered both, and with her mentor’s help, Dr. Corkin landed a position there. Thus began a decades-long collaboration between Dr. Corkin and Mr. Molaison that would extend the work of Dr. Milner, focus intense interest on the hippocampus, and make H.M. the most famous patient in the history of modern brain science. © 2016 The New York Times Company
Keyword: Learning & Memory
Link ID: 22258 - Posted: 05.28.2016
By Jordana Cepelewicz General consensus among Alzheimer’s researchers has it that the disease’s main culprit, a protein called amyloid beta, is an unfortunate waste product that is not known to play any useful role in the body—and one that can have devastating consequences. When not properly cleared from the brain it builds up into plaques that destroy synapses, the junctions between nerve cells, resulting in cognitive decline and memory loss. The protein has thus become a major drug target in the search for a cure to Alzheimer’s. Now a team of researchers at Harvard Medical School and Massachusetts General Hospital are proposing a very different story. In a study published this week in Science Translational Medicine, neurologists Rudolph Tanzi and Robert Moir report evidence that amyloid beta serves a crucial purpose: protecting the brain from invading microbes. “The original idea goes back to 2010 or so when Rob had a few too many Coronas,” Tanzi jokes. Moir had come across surprising similarities between amyloid beta and LL37, a protein that acts as a foot soldier in the brain’s innate immune system, killing potentially harmful bugs and alerting other cells to their presence. “These types of proteins, although small, are very sophisticated in what they do,” Moir says. “And they’re very ancient, going back to the dawn of multicellular life.” © 2016 Scientific American,