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By Carly Ledbetter Two years after “the dress” divided people over its color, the internet is back with another puzzling wardrobe question. What color are these shoes? Some people think these Vans sneakers look gray and mint (or teal), while others see pink and white. For some, the color changes the more they stare at the shoes: While others are dead-set on the color they see: Twitter user @dolansmalik explained one theory about why the shoes look like different colors to some people: “THE REAL SHOE IS PINK & WHITE OKAY?!” she wrote on Twitter. “The second pic was with flash & darkened, so it looks teal & gray. (depends on what lighting ur in).” Bevil Conway is an investigator with the National Eye Institute who helped contribute to a study on the differences in color perception for the famous “dress” controversy two years ago. He told HuffPost how and why our eyes play tricks on us, in situations like “the dress” and the shoes above. “This is related to the famous dress insofar as both are related to issues of color constancy,” he explained. “Basically your visual system is constantly trying to color correct the images projected on the retina, to remove the color contamination introduced by the spectral bias in the light source.” Conway explained just how and why some people see turquoise in the shoes, while others see pink. “In that manipulated photograph there is a lot of the turquoise cast over the whole image. When you first look at it, after having looked at the pink version, your visual system is still adapted to the lighting conditions of the pink version and so you see the turquoise in the other version, and you attribute this to the shoe itself,” he said. “But after a while, your visual system adapts to the turquoise across the whole of that image and interprets it as part of the light source, eventually discounting it and restoring the shoe to the original pink version (or at least pinker).” ©2018 Oath Inc.

Keyword: Vision
Link ID: 24575 - Posted: 01.26.2018

By Katarina Zimmer | Cellular senescence, the process by which cells cease to divide in response to stress, may be a double-edged sword. In addition to being an important anti-cancer mechanism, recent studies show it may also contribute to age-related tissue damage and inflammation. A study published in Cell Reports yesterday (January 23) suggests that cellular senescence could be a factor underlying neurodegeneration in sporadic forms of Parkinson’s disease. “I think the proposition that cellular senescence drives neurodegeneration in Parkinson’s disease and other ageing-related neurodegenerative diseases . . . has a great deal of merit,” writes D James Surmeier, a physiologist at Northwestern University, to The Scientist in an email. “To my knowledge, [this study] is the first strong piece of evidence for this model.” Cellular senescence may be the basis by which the herbicide and neurotoxin paraquat, which has been previously linked to Parkinson’s disease, can contribute to the disease, the researchers propose. The vast majority of Parkinson’s disease cases are sporadic, rather than inherited, and caused by a combination of environmental and genetic factors. Julie Andersen, a neuroscientist at the Buck Institute for Research on Aging, says her laboratory decided to focus on paraquat based on epidemiological evidence linking it to the condition in humans and on lab work showing that mice treated with the chemical suffer a loss of dopaminergic neurons in the same region that is affected in humans. It is an acutely toxic chemical—capable of causing death—and was banned in the E.U. in 2007 over safety concerns, but is still used extensively by American farmworkers. © 1986-2018 The Scientist

Keyword: Parkinsons; Glia
Link ID: 24574 - Posted: 01.26.2018

by Ariana Eunjung Cha A new class of epilepsy medications based on an ingredient derived from marijuana could be available as soon as the second half of 2018 in the United States, pending Food and Drug Administration approval. Officials from GW Pharmaceuticals, the company that developed the drug, on Wednesday announced promising results from a study on 171 patients randomized into treatment and placebo groups. Members of the group, ages 2 to 55, have a condition called Lennox-Gastaut syndrome and were suffering from seizures that were not being controlled by existing drugs. On average they had tried and discontinued six anti-seizure treatments and were experiencing 74 “drop” seizures per month. Drop seizures involve the entire body, trunk or head and often result in a fall or other type of injury. The results, published in the Lancet, show that over a 14-week treatment period, 44 percent of patients taking the drug, called Epidiolex, saw a significant reduction in seizures, compared with 22 percent of the placebo group. Moreover, more of the patients who got the drug experienced a 50 percent or greater reduction in drop seizures. Elizabeth Thiele, director of pediatric epilepsy at Massachusetts General Hospital and lead author of the study, said the results varied depending on the patient. “For some, it does not do a whole lot. But for the people it does work in, it is priceless,” she said. “One child who comes to mind had multiple seizures a day. She had been on every medication possible,” said Thiele, a professor of neurology at Harvard Medical School. Then the patient tried the cannabis-based treatment and has been seizure-free for almost four years. “She is now talking about college options. She would have never had that conversation before. It has been life-changing.” © 1996-2018 The Washington Post

Keyword: Epilepsy; Drug Abuse
Link ID: 24573 - Posted: 01.26.2018

Emmarie Huetteman Dr. Andrey Ostrovsky's family did not discuss what killed his uncle in 2015. The man was young, not quite two weeks past his 45th birthday, when he died, and had lost touch with loved ones in his final months. At the time, Ostrovsky wondered if his uncle had perhaps killed himself. Almost two years later, Ostrovsky was Medicaid's chief medical officer, grappling professionally with an opioid crisis that kills about 115 Americans each day, when he learned the truth: His uncle had died of a drug overdose. Family members knew the uncle's life had been turbulent for a while before his death; they'd watched as he divorced his wife and became estranged from his 4-year-old daughter and eventually lost his job as a furniture store manager. But Ostrovsky wanted to better understand what had happened to the man — his stepfather's younger brother. So last fall, when he found himself in southeastern Florida, where his uncle had died, Ostrovsky contacted one of the uncle's friends for what he expected would be a quick cup of coffee. Instead the friend "let loose," revealing that he and Ostrovsky's uncle had been experimenting with a variety of drugs the night of the death. It was the tragic culmination of more than a decade of substance abuse — a pattern of behavior much of the family knew nothing about. An autopsy showed there were opiates and cocaine in his uncle's system, Ostrovsky later learned. © 2018 npr

Keyword: Drug Abuse
Link ID: 24572 - Posted: 01.26.2018

By Shawna Williams When the Voyager I spacecraft left Earth in 1977, it carried with it a “Golden Record” containing audio recordings of messages meant for any intelligent life that might cross its path. It bore sounds from around the world, including greetings in 55 languages, Chuck Berry’s “Johnny B. Goode,” and a fussy baby being soothed by its mother. According to Marc Bornstein, a developmental psychologist at Eunice Kennedy Shriver National Institute of Child Health and Human Development, Carl Sagan and other members of the committee who decided what to include on the record were spot on in picking the latter track. “Infant cry is . . . the very first communication between an infant and a caregiver,” Bornstein says. Crying is infants’ best tool for ensuring they get the care they need, but Bornstein and his research collaborators wondered about the caregivers’ responses: to what extent were those innate versus learned? To investigate, they enrolled 684 new mothers and their babies from 11 countries around the world and put cameras in their homes. Each time a baby began crying, the researchers recorded what the mother did in the next five seconds. Did she pick the baby up? Kiss or stroke it? Talk to it? Try to distract it with a toy? “Within five seconds, the predominant kinds of responses are picking up and holding and talking to the baby,” says Bornstein (PNAS, 114:E9465-73, 2017). The degree of uniformity surprised him. “People in Kenya and Cameroon . . . the mothers are growing up and have been reared in wildly different circumstances than mothers in Brazil and Argentina or the United States, or certainly than Japan or South Korea.” © 1986-2018 The Scientist

Keyword: Sexual Behavior; Language
Link ID: 24571 - Posted: 01.26.2018

Ewen Callaway The oldest human fossils ever found outside Africa suggest that Homo sapiens might have spread to the Arabian Peninsula around 180,000 years ago — much earlier than previously thought. The upper jaw and teeth, found in an Israeli cave and reported in Science on 25 January1, pre-date other human fossils from the same region by at least 50,000 years. But scientists say that it is unclear whether the fossils represent a brief incursion or a more-lasting expansion of the species. Researchers originally thought that H. sapiens emerged in East Africa 200,000 years ago then moved out to populate the rest of the world. Until discoveries in the past decade countered that story, scientists thought that a small group left Africa some 60,000 years ago and that signs of earlier travels, including 80,000–120,000 year-old skulls and other remains from Israel discovered in the 1920s and 1930s, were from failed migrations. However, recent discoveries have muddied that simple narrative. Some H. sapiens-like fossils from Morocco that are older than 300,000 years, reported last year2, have raised the possibility that humans evolved earlier and perhaps elsewhere in Africa. Teeth from southern China, described in 20153, hint at long-distance migrations some 120,000 years ago. And genome studies have sown more confusion, with some comparisons of global populations pointing to just one human migration from Africa4,5, and others suggesting multiple waves6. © 2018 Macmillan Publishers Limited,

Keyword: Evolution
Link ID: 24570 - Posted: 01.26.2018

Laura Sanders People tend to think of memories as deeply personal, ephemeral possessions — snippets of emotions, words, colors and smells stitched into our unique neural tapestries as life goes on. But a strange series of experiments conducted decades ago offered a different, more tangible perspective. The mind-bending results have gained unexpected support from recent studies. In 1959, James Vernon McConnell, a psychologist at the University of Michigan in Ann Arbor, painstakingly trained small flatworms called planarians to associate a shock with a light. The worms remembered this lesson, later contracting their bodies in response to the light. One weird and wonderful thing about planarians is that they can regenerate their bodies — including their brains. When the trained flatworms were cut in half, they regrew either a head or a tail, depending on which piece had been lost. Not surprisingly, worms that kept their heads and regrew tails retained the memory of the shock, McConnell found. Astonishingly, so did the worms that grew replacement heads and brains. Somehow, these fully operational, complex arrangements of brand-spanking-new nerve cells had acquired the memory of the painful shock, McConnell reported. In subsequent experiments, McConnell went even further, attempting to transfer memory from one worm to another. He tried grafting the head of a trained worm onto the tail of an untrained worm, but he couldn’t get the head to stick. He injected trained planarian slurry into untrained worms, but the recipients often exploded. Finally, he ground up bits of the trained planarians and fed them to untrained worms. Sure enough, after their meal, the untrained worms seemed to have traces of the memory — the cannibals recoiled at the light. The implications were bizarre, and potentially profound: Lurking in that pungent planarian puree must be a substance that allowed animals to literally eat one another’s memories. |© Society for Science & the Public 2000 - 2017.

Keyword: Learning & Memory
Link ID: 24569 - Posted: 01.25.2018

By Lenny Bernstein Advanced brain imaging technology may give doctors an additional 10 hours or more to respond to some strokes, researchers said Wednesday, a development that may soon bring major changes to the way hospitals treat one of the leading causes of disability and death. The research is upending doctors’ long-held belief that they have just six hours to save threatened brain tissue from lack of blood flow when a major vessel to the brain is blocked. The new findings suggest they may have as long as 16 hours in many cases; a study published three weeks ago with a different group of stroke victims put the outer limit at 24 hours for some. Both studies showed such dramatic results that they were cut short to speed up reporting of the information to physicians. In response to the studies, new stroke treatment guidelines were released Wednesday. “The big news is that we were all wrong in how we were thinking about how strokes evolve,” said Gregory W. Albers, a professor of neurology at Stanford University Medical Center and lead author of the new paper. While some brain tissue dies quickly after a stroke begins, in most patients, collateral blood vessels usually take over feeding a larger area of the brain that is also starved for blood and oxygen, giving doctors many more hours to save that tissue than they previously believed, Albers said. So the age-old medical belief that “time is brain” — that millions of neurons die each minute after a stroke — must be reconsidered, he said. “We are quadrupling the stroke treatment window today,” Albers said. “It’s going to have a massive impact on how stroke is triaged and assessed.” © 1996-2018 The Washington Post

Keyword: Stroke
Link ID: 24568 - Posted: 01.25.2018

By Bret Stetka Fossil records can tell us a lot about our evolutionary past: what our ancestors looked like, how they walked, what they ate. But what bits of bone don’t typically reveal is why humans evolved the way we did—why, compared with all other known species, we wound up capable of such complex thought, emotion and behavior. A team of researchers has now used a novel technique to form a hypothesis on the origins of our rich cognitive abilities. They did so by profiling the chemicals buzzing around our brains. These compounds, known as neurotransmitters, are the signaling molecules responsible for key brain functions. Their research reveals that in comparison with other higher primates, our brains have unique neurotransmitter profiles that probably resulted in our enhanced cognition. The authors of the new study—a multicenter effort led by Kent State University anthropologists C. Owen Lovejoy and Mary Ann Raghanti and published January 22 in PNAS—began by measuring neurotransmitter levels in brain samples from humans, chimpanzees, gorillas, baboons and monkeys, all of whom had died of natural causes. Specifically, they tested levels in the striatum, a brain region involved in social behaviors and interactions. Compared with the other species tested, humans had markedly increased striatal dopamine activity. Among other functions, dopamine helps drive reward activity and social behaviors. In the striatum in particular it contributes to uniquely human abilities and behaviors like complicated social group formation and, in part, speech and language. © 2018 Scientific American,

Keyword: Evolution
Link ID: 24567 - Posted: 01.25.2018

Bruce Bower Big brains outpaced well-rounded brains in human evolution. Around the time of the origins of our species 300,000 years ago, the brains of Homo sapiens had about the same relatively large size as they do today, new research suggests. But rounder noggins rising well above the forehead — considered a hallmark of human anatomy — didn’t appear until between about 100,000 and 35,000 years ago, say physical anthropologist Simon Neubauer and his colleagues. Using CT scans of ancient and modern human skulls, the researchers created digital brain reconstructions, based on the shape of the inner surface of each skull’s braincase. Human brains gradually evolved from a relatively flatter and elongated shape — more like that of Neandertals’ — to a globe shape thanks to a series of genetic tweaks to brain development early in life, the researchers propose January 24 in Science Advances. A gradual transition to round brains may have stimulated considerable neural reorganization by around 50,000 years ago. That cognitive reworking could have enabled a blossoming of artwork and other forms of symbolic behavior among Stone Age humans, the team suspects. Other researchers have argued, however, that abstract and symbolic thinking flourished even before H. sapiens emerged (SN: 12/27/14, p. 6). Ancient DNA studies indicate that genes involved in brain development changed in H. sapiens following a split from Neandertals more than 600,000 years ago (SN Online: 3/14/16). “Those genetic changes might be responsible for differences in neural wiring and brain growth that led to brain [rounding] in modern humans, but not in Neandertals,” says Neubauer of the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany. |© Society for Science & the Public 2000 - 2017

Keyword: Evolution
Link ID: 24566 - Posted: 01.25.2018

By Diana Kwon Search for “pheromones products” on the internet, and dozens of sprays and perfume additives will appear—many claiming to be able to increase your attractiveness to the opposite sex. Some companies, such as the Athena Institute, which, according to its founder, Winnifred Cutler, published its 108th consecutive ad in The Atlantic this month, assert that scientific studies back up their claims. While there have been several experiments examining the effects of compounds extracted from people’s armpits, much of the data on sex-related behaviors, The Scientist has found, go back more than a decade and were met then—and still now—with skepticism from pheromone researchers. “I am not compelled by any studies that are out there that say there is an active steroid component from the underarm that causes [sexual attraction],” says George Preti, an organic chemist at the Monell Chemical Senses Center in Philadelphia who conducted some of the early human pheromone trials. Within the scientific community, pheromones are broadly defined as chemical signals released by an animal that induce specific effects on other members of the same species. Although these substances are typically associated with sexual attraction, researchers have found they can have a broader range of influence, such as prompting aggression or modifying parental behaviors. © 1986-2018 The Scientist

Keyword: Chemical Senses (Smell & Taste); Sexual Behavior
Link ID: 24565 - Posted: 01.25.2018

Dean Burnett Doctors Warn That Anti-Depressants Can Lead To SuicideMIAMI, FL - MARCH 23: A bottle of antidepressant pills named Effexor is shown March 23, 2004 photographed in Miami, Florida. The Food and Drug Administration asked makers of popular antidepressants to add or strengthen suicide-related warnings on their labels as well as the possibility of worsening depression especially at the beginning of treatment or when the doses are increased or decreased. (Photo Illustration by Joe Raedle/Getty Images) Please, do not just abandon your medication. If you’ve been prescribed drugs to treat an illness, suddenly dropping it altogether – for whatever reason – is invariably a very bad move. And this is as true for things like antidepressants as it is for insulin or antibiotics. Antidepressant withdrawal syndrome is a real problem. It doesn’t effect everyone equally, but that’s always been the case with antidepressants. The effects can be really profound and debilitating though, including a spike in anxiety, alarming “brain zaps”, and more. For better or worse, if you’ve been taking antidepressants for a number of weeks, your brain has slowly adapted to the new chemical levels and balance that they have brought about. A sudden cessation will rapidly alter this again, potentially causing all manner of problems, and possibly cause the underlying issue (ie depression) they’re supposed to be treating to return with a vengeance. This is why the specific dose and schedule of antidepressants is very carefully considered. If you do genuinely want to come off your antidepressants, please speak to your GP or medical expert, work out a system for gradual reduction and cessation and make plans and preparations for what could happen, as it could leave you unable to function normally. If you’re going to do it, please do it carefully, and thoroughly. © 2018 Guardian News and Media Limit

Keyword: Depression
Link ID: 24564 - Posted: 01.25.2018

By Alex Therrien Health reporter, BBC News Smokers need to quit cigarettes rather than cut back on them to significantly lower their risk of heart disease and stroke, a large BMJ study suggests. People who smoked even one cigarette a day were still about 50% more likely to develop heart disease and 30% more likely to have a stroke than people who had never smoked, researchers said. They said it showed there was no safe level of smoking for such diseases. But an expert said people who cut down were more likely to stop. Cardiovascular disease, not cancer, is the greatest mortality risk for smoking, causing about 48% of smoking-related premature deaths. While the percentage of adults in the UK who smoked had been falling, the proportion of people who smoked one to five cigarettes a day had been rising steadily, researchers said. Their analysis of 141 studies, published in the BMJ, indicates a 20-a-day habit would cause seven heart attacks or strokes in a group of 100 middle-aged people. But if they drastically cut back to one a day it would still cause three heart attacks, the research suggests. The researchers said men who smoked one cigarette a day had about a 48% higher risk of developing coronary heart disease and were 25% more likely to have a stroke than those who had never smoked. For women, it was higher - 57% for heart disease and 31% for stroke. Prof Allan Hackshaw at the UCL Cancer Institute at University College London, who led the study, told the BBC: "There's been a trend in quite a few countries for heavy smokers to cut down, thinking that's perfectly fine, which is the case for things like cancer. "But for these two common disorders, which they're probably more likely to get than cancer, it's not the case. They've got to stop completely." © 2018 BBC.

Keyword: Drug Abuse
Link ID: 24563 - Posted: 01.25.2018

Ian Sample Science editor In work that could open a new front in the war on Parkinson’s disease, and even ageing itself, scientists have shown that they can stave off some of the effects of the neurodegenerative disease by flushing “zombie cells” from the brain. The research in mice raises hopes for a fresh approach to treating the most common forms of Parkinson’s disease, which typically arise through a complex interplay of genetics, lifestyle and potentially toxic substances in the environment. But the approach may have benefits far beyond Parkinson’s, with other neurodegenerative diseases – and the ageing process more broadly – all being linked to the ill effects of these “senescent” cells, which linger in tissues after entering a state of suspended animation in the body. “It’s a completely new way of looking at neurodegenerative disease and finding potential drugs,” said Marco Demaria, a molecular biologist on the team at the University of Groningen in the Netherlands. “For most of these conditions, we don’t have any way to counteract them.” Parkinson’s disease affects about 10 million people worldwide, and usually takes hold when certain types of neurons in the brain become impaired or die off completely. The neurons in question produce a substance called dopamine, which is crucial for enabling the brain to produce smooth and coordinated physical movements. © 2018 Guardian News and Media Limited

Keyword: Parkinsons
Link ID: 24562 - Posted: 01.24.2018

Patti Neighmond Kids who vape and use other forms of e-cigarettes are likely to try more harmful tobacco products like regular cigarettes, but e-cigarettes do hold some promise for helping adults quit. That's according to the National Academies of Science, Engineering and Medicine, which published a comprehensive public health review of more than 800 studies on e-cigarettes on Tuesday. "There is conclusive evidence that most products emit a variety of potentially toxic substances. However the number and intensity is highly variable," says David Eaton, who heads the committee that wrote the report. He is also the dean and vice provost of the graduate school of the University of Washington, Seattle. "In some circumstances, such as their use by nonsmoking adolescents and young adults, their adverse effects clearly warrant concern. In other cases, such as when adult smokers use them to quit smoking, they offer an opportunity to reduce smoking-related illness." In fact, 15 of the studies NAS reviewed found that when teens and young adults use e-cigarettes, they are more likely to try regular tobacco within a year. "We found that kids who tried e-cigarettes, hookah, or smokeless tobacco or cigars — any non-cigarette tobacco product — were all twice as likely to try cigarettes a year later, compared to kids who hadn't used any of those other tobacco products," says Shannon Lea Watkins, a public policy researcher at University of California, San Francisco. Watkins and her colleagues also found that the effects of using non-cigarette products compound: "Kids using two or more non-cigarette products were four times as likely to report using cigarettes a year later." © 2018 npr

Keyword: Drug Abuse
Link ID: 24561 - Posted: 01.24.2018

By Giorgia Guglielmi ENIGMA, the world’s largest brain mapping project, was “born out of frustration,” says neuroscientist Paul Thompson of the University of Southern California in Los Angeles. In 2009, he and geneticist Nicholas Martin of the Queensland Institute of Medical Research in Brisbane, Australia, were chafing at the limits of brain imaging studies. The cost of MRI scans limited most efforts to a few dozen subjects—too few to draw robust connections about how brain structure is linked to genetic variations and disease. The answer, they realized over a meal at a Los Angeles shopping mall, was to pool images and genetic data from multiple studies across the world. After a slow start, the consortium has brought together nearly 900 researchers across 39 countries to analyze brain scans and genetic data on more than 30,000 people. In an accelerating series of publications, ENIGMA’s crowdsourcing approach is opening windows on how genes and structure relate in the normal brain—and in disease. This week, for example, an ENIGMA study published in the journal Brain compared scans from nearly 4000 people across Europe, the Americas, Asia, and Australia to pinpoint unexpected brain abnormalities associated with common epilepsies. ENIGMA is “an outstanding effort. We should all be doing more of this,” says Mohammed Milad, a neuroscientist at the University of Illinois in Chicago who is not a member of the consortium. ENIGMA’s founders crafted the consortium’s name—Enhancing NeuroImaging Genetics through Meta-Analysis—so that its acronym would honor U.K. mathematician Alan Turing’s code-breaking effort targeting Germany’s Enigma cipher machines during World War II. Like Turing’s project, ENIGMA aims to crack a mystery. Small brain-scanning studies of twins or close relatives done in the 2000s showed that differences in some cognitive and structural brain measures have a genetic basis. © 2018 American Association for the Advancement of Science.

Keyword: Brain imaging; Genes & Behavior
Link ID: 24560 - Posted: 01.24.2018

By Benjamin W. Nelson, Heidemarie Laurent, Nick Allen, An estimated 1 in 9 women experience symptoms of postpartum depression. These symptoms—including mood swings, fatigue and reduced interest in activities—can make it difficult for mothers to bond with their newborns. Early relationships between mothers and their infants can influence health across the lifespan, for better or worse. For example, adults who report more household dysfunction and abuse during their childhood are more likely to suffer disease as adults. Those with healthy and supportive relationships during early life are better at handling stress and regulating their emotions. Advertisement However, scientists do not completely understand how these environments get “under the skin” to shape health. Our latest paper, published in November, shows a possible link between increasing depression symptoms in mothers and cellular damage in their infants. How does stress affect our cells? One area of burgeoning research focuses on telomeres. Telomeres are caps at the end of our DNA that protect chromosomes. They’re analogous to the plastic tips at the end of shoelaces that keep laces from unraveling. In essence, these plastic caps keep laces functional. The same can be said of your telomeres. Since the length of telomeres is affected by our genetics and age, they’re sometimes thought of as part of a “biological clock” that reflects the age of our cells. As telomeres shorten over time, people are more likely to experience a host of negative health outcomes, such as cardiovascular disease, dementia, diabetes, cancer, obesity and even death. © 2018 Scientific American

Keyword: Depression; Development of the Brain
Link ID: 24559 - Posted: 01.24.2018

By LIZZ SCHUMER It happens every year, and every year, it’s a shock to the system. Nature throws itself one last party, festooning every tree in a crisp blaze of glory. After we’ve digested the last of the spiced cider, after the pumpkins have gone soft, the long, dark days of winter descend. In much of the Northern Hemisphere, December through March brings blustery cold that makes dreary days feel as if we’ve been banished to Siberia. Sound dramatic? Probably not to the roughly 6 percent of Americans suffering from Seasonal Affective Disorder. Dr. Norman E. Rosenthal and his colleagues first put a name to the disorder in 1984. Today, it’s characterized as a seasonal pattern of major depressive episodes, according to the Diagnostic and Statistical Manual of Mental Disorders. SAD ranges widely in severity, from the doldrums Dr. Rosenthal calls the “winter blues” to disabling ennui. Its cyclical nature differentiates SAD from major depressive disorder. “We have a tendency to want to blame everything on psychological causes,” Dr. Rosenthal explained. “We overlook the obvious, which is that it’s dark as pea soup outside. That’s why I think [SAD] goes unrecognized — it’s right in front of our noses.” While SAD should be diagnosed and treated by a licensed medical professional, several treatment options have emerged in the decades since it was first recognized. Here are a few ways for patients and their doctors to address the disorder, ranging from most to least widely used. © 2018 The New York Times Company

Keyword: Depression; Biological Rhythms
Link ID: 24558 - Posted: 01.24.2018

By Abby Olena Studying scorpions comes with its share of danger, as biologist Bryan Fry of the University of Queensland knows all too well. On a 2009 trip to the Brazilian Amazon, Fry was stung while trying to collect the lethal Brazilian yellow scorpion (Tityus serrulatus), and for eight hours he says it felt as though his finger was in a candle flame. Meanwhile, his heart flipped between racing and stopping for up to five seconds at a time. “At least the insane levels of pain helped keep my mind off my failing heart,” Fry writes in an email to The Scientist. His symptoms were caused by an arsenal of toxins in the animal’s sting, which contribute to one of the most painful attacks in the animal kingdom. But at least one mammal—the southern grasshopper mouse (Onychomys torridus)—regularly chows down on Arizona bark scorpions (Centruroides sculpturatus) and doesn’t seem to experience pain, despite receiving plenty of stings. In 2013, Ashlee Rowe, now of Michigan State University, and colleagues showed that bark scorpion venom interacts with the NaV1.8 voltage-gated sodium channel in grasshopper mice, in addition to activating the NaV1.7 channel as it does in other mammals (Science, 342:441-46). Rowe’s team showed that grasshopper mice have evolved amino acid changes in NaV1.8 that allow it to bind scorpion venom components, and in turn prevent the channel’s activation. Because NaV1.8 is responsible for transmitting pain signals to the central nervous system following NaV1.7 binding, blocking its activation prevents the sensation of pain. In other mammals, scorpion venom has no effect on NaV1.8. © 1986-2018 The Scientist

Keyword: Pain & Touch; Neurotoxins
Link ID: 24557 - Posted: 01.24.2018

By Jocelyn Kaiser Scientists who conduct basic behavioral research are bracing for a policy kicking in this week that will impose new rules on their federally funded studies, many of which the National Institutes of Health (NIH) in Bethesda, Maryland, will now consider clinical trials. Although many researchers maintain that the policy makes no sense and will hinder their work, recent revisions by NIH officials have eased some fears. “There’s still a problem, but the problem is less dire than the original set of concerns that we had,” says cognitive psychologist Jeremy Wolfe of the Harvard University–affiliated Brigham and Women’s Hospital in Boston, who is also the immediate past president of the Federation of Associations in Behavioral & Brain Sciences (FABBS) in Washington, D.C. The changes, which take effect for proposals with due dates of 25 January or later, are part of a new clinical trials definition that NIH released in 2014 but only began implementing last year. That was when scientists who use tools such as MRI scans to explore how the normal brain works realized that their studies, which they never thought of as clinical trials because they don’t test drugs or other treatments, fell under the new definition. The change imposed several new requirements on researchers, such as submitting proposals in response to a formal funding opportunity for clinical trials and registering the studies in clinicaltrials.gov, the federal trials database. © 2018 American Association for the Advancement of Science

Keyword: Vision
Link ID: 24556 - Posted: 01.24.2018