by Simon Makin Sometimes wacky-sounding ideas aren't so crazy after all. If your body clock is all at sea after a long flight or a night shift, the way to reset it may be to scramble your timekeeping neurons even further. The body's master clock resides in a region of the brain called the suprachiasmatic nucleus. Each neuron in the SCN keeps its own time, but the neurons can synchronise their clocks by sending and receiving signals using a hormone called vasoactive intestinal polypeptide (VIP). When Erik Herzog at Washington University in St Louis, Missouri, and colleagues probed the hormone's effects, they discovered that a glut of VIP caused the neurons to lose the ability to synchronise. Herzog's team wondered whether this might have a beneficial effect. "If the cell rhythms are messed up and out of phase, the system may be more sensitive to environmental cues than it would be if all the cells were in sync," he says, allowing the body clock to adjust more readily. The VIP treatment To test the idea, they gave some mice an injection of VIP into the brain before fast-forwarding the light/dark cycle in their cages by 8 hours. The mice that received the hormone adjusted in 4.5 days on average, whereas untreated mice needed nearly eight days – gauging by how active the animals were when the lights were off. © Copyright Reed Business Information Ltd.

Keyword: Biological Rhythms
Link ID: 18855 - Posted: 10.30.2013

By Cheryl G. Murphy Is it possible that our vision can affect our taste perception? Let’s review some examples of studies that claim to have demonstrated that sometimes what we see can override what we think we taste. From wine to cheese to soft drinks and more it seems that by playing with the color palette of food one can trick our palates into thinking we taste things that aren’t necessarily there. © 2013 Scientific American

Keyword: Chemical Senses (Smell & Taste); Vision
Link ID: 18854 - Posted: 10.30.2013

by Tina Hesman Saey BOSTON— Siberians may use genes to stay warm, a new study shows. As part of an effort to catalog genetic diversity in Siberia, Alexia Cardona of the University of Cambridge and collaborators sampled DNA from 200 Siberians representing 10 native groups. The team looked for genes that have more changes in Siberians than would be expected by chance — a sign that the genes evolved rapidly in the 24,000 years since people settled the frigid land. Rapid changes suggest that a gene is important for adapting to an environment. Several of the Siberians’ genes have variants that may help keep Arctic dwellers warm during the long winters, Cardona reported October 24 at the annual meeting of the American Society of Human Genetics. Among the candidates for genetic heaters are genes involved in metabolizing fats. Some Siberian groups eat mostly meat, so genes that help convert animal fat to energy are important for creating heat. Another gene with variants unique to Siberians is called PRKG1; it helps regulate body heat by controlling muscle contraction and the constriction and dilation of blood vessels. Muscle contractions are an important part of shivering, which can raise body temperature. The researchers also identified variants in genes involved in thyroid function, which plays a role in temperature regulation. A. Cardona et al. Genome-wide analysis of cold adaption in indigenous Siberian populations. American Society of Human Genetics annual meeting, Boston, October 24, 2013. © Society for Science & the Public 2000 - 2013

Keyword: Genes & Behavior; Evolution
Link ID: 18853 - Posted: 10.30.2013

Reindeer may have a unique way of coping with the perpetual darkness of Arctic winters: During that season, their eyes become far more sensitive to light. Like many vertebrates and most mammals, especially those that are nocturnal, reindeer (Rangifer tarandus) have a light-reflecting layer of collagen-containing tissue behind the retinas of their eyes. This structure, called the tapetum lucidum (Latin for “bright tapestry”), gives the eye’s light-sensitive neurons a second chance to detect scarce photons in low-light conditions. (The layer also produces the “eyeshine” that can make animal eyes appear to glow in the dark.) During sunny months, reindeer have yellow eyeshine. But in the wintertime, light reflected from the tapetum lucidum takes on a decidedly bluish sheen—a seasonal shift that hasn’t been noted in other mammals, the researchers say. To study this unusual color change, the researchers brought some disembodied reindeer eyeballs into the lab and placed small weights on them. When under pressure, the eyeballs changed the color of eyeshine almost immediately. That fits with what happens in the wild over the course of seasons, the researchers say. In winter, reindeer pupils are constantly dilated, which increases fluid pressure. That, in turn, decreases the spacing of collagen fibers in the tapetum lucidum, further increasing the scattering of light within the eye and shifting the reflected light toward the lower wavelengths of light which are predominant at dusk. These changes make the reindeer’s eyes between 100 and 1000 times more light-sensitive, the researchers report today in the Proceedings of the Royal Society B. Although this decreases the creature’s sharpness of vision, it’s a tradeoff that, on the whole, probably boosts reindeer survival by helping them better detect predators in the dark, the researchers contend. © 2013 American Association for the Advancement of Science

Keyword: Vision
Link ID: 18852 - Posted: 10.30.2013

Melissa Dahl TODAY You know smoking doesn’t do any favors for your face – or your lungs, or your heart, or just about any other part of your body, for that matter! – but a new study of twins hints at the ways the habit makes you look older than you really are. In what is perhaps the best detail of the study, researchers used the annual Twins Days Festival in Twinsburg, Ohio (the "Largest Annual Gathering of Twins in the World!") to round up the 79 identical pairs they include in the report. A panel of three plastic surgery residents compared the faces of the twins, one of which had been smoking for at least five years longer than the other. They identified a few major areas of accelerated aging in the faces of the smoking twins: The smokers' upper eyelids drooped while the lower lids sagged, and they had more wrinkles around the mouth. The smokers were also more likely to have jowls, according to the study, which was published today in the journal Plastic and Reconstructive Surgery. Smoking reduces oxygen to the skin, which also decreases blood circulation, and that can result in weathered, wrinkled, older-looking skin, explains Dr. Bahman Guyuron, a plastic surgeon in Cleveland, Ohio, and the lead author of the study. The logic of research like this and others like it is this: If threats of cancer, heart and lung disease, or the dangers of second- and third-hand smoke aren’t enough to get people to stop smoking, or to never start in the first place, then why not try appealing to people’s vanity? (The same tactic has been used in an attempt to warn young people away from tanning.)

Keyword: Drug Abuse
Link ID: 18851 - Posted: 10.30.2013

Think fast. The deadly threat of snakes may have driven humans to develop a complex and specialized visual system. The sinuous shape triggers a primal jolt of recognition: snake! A new study of the monkey brain suggests that primates are uniquely adapted to recognize the features of this slithering threat and react in a flash. The results lend support to a controversial hypothesis: that primates as we know them would never have evolved without snakes. A tussle with a snake meant almost certain death for our preprimate ancestors. The reptiles slithered through the forests of the supercontinent Gondwana roughly 100 million years ago, squeezing the life out of the tiny rodent-sized mammalian ancestors of modern primates. About 40 million years later, likely after primates had emerged, some snakes began injecting poison, which made them an even deadlier and more immediate threat. Snakes were “the first and most persistent predators” of early mammals, says Lynne Isbell, a behavioral ecologist the University of California, Davis. They were such a critical threat, she has long argued, that they shaped the emergence and evolution of primates. By selecting for traits that helped animals avoid them, snakes ultimately endowed us with forward-facing eyes, for example, and enlarged visual centers deep in our brains that are specialized for picking out specific features in the world around us, such as the general shape of a snake’s body camouflaged among leaves. Isbell published her “Snake Detection Theory” in 2006. To support it, she showed that the rare primates that have not encountered venomous snakes in the course of their evolution, such as lemurs in Madagascar, have poorer vision than those that evolved alongside snakes. © 2013 American Association for the Advancement of Science

Keyword: Vision; Evolution
Link ID: 18850 - Posted: 10.29.2013

By Daisy Yuhas For more than a century researchers have been trying and failing to link perception and intelligence—for instance, do intelligent people see more detail in a scene? Now scientists at the University of Rochester and at Vanderbilt University have demonstrated that high IQ may be best predicted by combining what we perceive and what we cannot. In two studies in the journal Current Biology, researchers asked 67 people to take IQ tests. They then viewed milli-second-long video clips in which black-and-white stripes moved left or right. The split-second films challenged viewers: the stripes moved within a circular frame that could differ in size, varying from the width of a thumb to a fist held at arm's length. After each clip, the viewers guessed whether the bars moved toward the left or right. The investigators discovered that performance on this test was more correlated with IQ than any other sensory-intelligence link ever explored—but the high-IQ participants were not simply scoring better overall. Individuals with high IQ indeed detected movement accurately within the smallest frame—a finding that suggests, perhaps unsurprisingly, that the ability to rapidly process information contributes to intelligence. More intriguing was the fact that subjects who had higher IQ struggled more than other subjects to detect motion in the largest frame. The authors suggest that the brain may perceive large objects as background and subsequently may try to ignore their movements. “Suppressing information is a really important thing that the brain does,” explains University of Rochester neuroscientist Duje Tadin. He explains that the findings underscore how intelligence requires that we think fast but focus selectively, ignoring distractions. © 2013 Scientific American

Keyword: Vision; Intelligence
Link ID: 18849 - Posted: 10.29.2013

By KATE MURPHY Whether it’s hitting a golf ball, playing the piano or speaking a foreign language, becoming really good at something requires practice. Repetition creates neural pathways in the brain, so the behavior eventually becomes more automatic and outside distractions have less impact. It’s called being in the zone. But what if you could establish the neural pathways that lead to virtuosity more quickly? That is the promise of transcranial direct current stimulation, or tDCS — the passage of very low-level electrical current through targeted areas of the brain. Several studies conducted in medical and military settings indicate tDCS may bring improvements in cognitive function, motor skills and mood. Some experts suggest that tDCS might be useful in the rehabilitation of patients suffering from neurological and psychological disorders, perhaps even in reducing the time and expense of training healthy people to master a skill. But the research is preliminary, and now there is concern about a growing do-it-yourself community, many of them video gamers, who are making tDCS devices with nine-volt batteries to essentially jump-start their brains. “If tDCS is powerful enough to do good, you have to wonder if, done incorrectly, it could cause harm,” said Dr. H. Branch Coslett, chief of the cognitive neurology section at the University of Pennsylvania School of Medicine and a co-author of studies showing that tDCS improves recall of proper names, fosters creativity and improves reading efficiency. Even the tDCS units used in research are often little more than a nine-volt battery with two electrodes and a controller for setting the current and the duration of the session. Several YouTube videos show how to make a rough facsimile. © 2013 The New York Times Company

Keyword: Miscellaneous
Link ID: 18848 - Posted: 10.29.2013

Early childhood poverty has been linked to smaller brain size by U.S. researchers who are pointing to the importance of nurturing from caregivers as a protective factor. Children exposed to poverty tend to have poorer cognitive outcomes and school performance. To learn more about the biology of how, researchers started tracking the emotional and brain development of 145 preschoolers in metropolitan St. Louis for 10 years. Household poverty was measured by the income-to-needs ratio. Children were assessed each year for thee to six years before they received an MRI and questionnaires. A parent and child were also observed during a lab task that required the child (age four to seven) to wait for eight minutes before opening a brightly wrapped gift within arm's reach while the parent filled in questionnaires. "These study findings demonstrated that exposure to poverty during early childhood is associated with smaller white matter, cortical grey matter, and hippocampal and amygdala volumes," Dr. Joan Luby of the psychiatry department at Washington University School of Medicine in St. Louis and her co-authors concluded in Monday's issue of the journal JAMA Pediatrics. The findings were consistent with an earlier study by the same team that suggested supportive parenting also plays an important role in the development of the hippocampus in childhood independent of income. The brain's hippocampus is important for learning and memory and how we respond to stress. In the study, the effects of poverty on hippocampal volume was influenced by caregiving support or hospitality in the brain's light and right hemispheres and stressful life events on the left. Caregiver education was not a significant mediator. © CBC 2013

Keyword: Development of the Brain; Learning & Memory
Link ID: 18847 - Posted: 10.29.2013

By David Dobbs If you want a look at a high-profile field dealing with a lot of humbling snags, peer into #ASHG2013, the Twitter hashtag for last week’s meeting of the American Society of Human Genetics, held in Boston. You will see successes, to be sure: Geneticists are sequencing and analyzing genomes ever faster and more precisely. In the last year alone, the field has quintupled the rate at which it identifies genes for rare diseases. These advances are leading to treatments and cures for obscure illnesses that doctors could do nothing about only a few years ago, as well as genetic tests that allow prospective parents to bear healthy children instead of suffering miscarriage after miscarriage. But many of the tweets—or any frank geneticist—will also tell you stories of struggle and confusion: The current list of cancer-risk genes, the detection of which leads some people to have “real organs removed,” likely contains many false positives, even as standard diagnostic sequencing techniques are missing many disease-causing mutations. There’s a real possibility that the “majority of cancer predisposition genes in databases are wrong.” And a sharp team of geneticists just last week cleanly dismantled a hyped study from last year that claimed to find a genetic signature of autism clear enough to diagnose the risk of it in unborn children. This sample reads like an abstract of the entire field of genetics. In researching a book about genetics over the past four years, I’ve found a field that stands in a bizarre but lovely state of confusion—taken aback, but eager to advance; balanced tenuously between wild ambition and a deep but troubling humility. In the 13 years since the sequencing of the first human genome, the field has solved puzzles that 14 years ago seemed hopeless. Yet geneticists with any historical memory hold a painful awareness that their field has fallen short of the glory that seemed close at hand when Francis Collins, Craig Venter, and Bill Clinton announced their apparent triumph in June 2000. © 2013 The Slate Group, LLC

Keyword: Genes & Behavior
Link ID: 18846 - Posted: 10.29.2013

By JAN HOFFMAN There are activities common to most humans that we enjoy immensely, without much thought, and as frequently as opportunity and instinct provide. On occasion, researchers feel they need to know why. Recently, experimental psychologists at Oxford University explored the function of kissing in romantic relationships. Surprise! It’s complicated. After conducting an online survey with 308 men and 594 women, mostly from North America and Europe, who ranged in age from 18 to 63, the researchers have concluded that kissing may help people assess potential mates and then maintain those relationships. “The repurposing of the behavior is very efficient,” said Rafael Wlodarski, a doctoral candidate and lead author of the study, published in Archives of Sexual Behavior. But another hypothesis about kissing — that its function is to elevate sexual arousal and ready a couple for coitus — didn’t hold up. While that might be an outcome, researchers did not find sexual arousal to be the primary driver for kissing. Participants in the survey were asked about their attitudes toward kissing in different phases of romantic relationships. They were then asked about their sexual history: for example, whether they had been more inclined toward casual encounters or long-term, committed relationships. They also had to define their “mate value” by assessing their own attractiveness. Later, during data analysis, the researchers looked at how individual differences affected a person’s thoughts on kissing. Copyright 2013 The New York Times Company

Keyword: Sexual Behavior
Link ID: 18845 - Posted: 10.29.2013

By Amanda Mascarelli, When my son was in preschool, I did what many parents of excessively energetic and impulsive preschoolers have surely done: I worried whether his behavior might be a sign of attention-deficit hyperactivity disorder (ADHD). Then I sought input from two pediatricians and a family therapist. The experts thought that his behavior was developmentally normal but said it was still too early to tell for sure. They offered some tips on managing his behavior and creating more structure at home. One pediatrician worked with my son on self-calming techniques such as breathing deeply and pushing on pressure points in his hands. He also suggested an herbal supplement, Valerian Super Calm, for him to take with meals and advised us on dietary adjustments such as increasing my son’s intake of fatty acids. Studies have shown that a combination of omega-3 (found in foods such as walnuts, flaxseed and salmon) and omega-6 fatty acids (from food oils such as canola and flax) can reduce hyperactivity and other ADHD symptoms in some children. In the couple of years since trying these techniques, my son has outgrown most of those worrisome behaviors. I had just about written off the possibility of ADHD until a few weeks ago, when his kindergarten teacher mentioned that she was going to keep an eye on him for possible attention issues. Hearing that left me worried and heavy-hearted. Why is it still so hard to diagnose ADHD? And why is there so much emotional baggage associated with treating it? There are no firm numbers for the number of children with ADHD in the United States. The Centers for Disease Control and Prevention estimates that 9 percent of U.S. children ages 5 to 17 had received diagnoses of ADHD as of 2009. © 1996-2013 The Washington Post

Keyword: ADHD; Development of the Brain
Link ID: 18844 - Posted: 10.29.2013

By James Gallagher Health and science reporter, BBC News A clearer picture of what causes Alzheimer's disease is emerging after the largest ever analysis of patients' DNA. A massive international collaboration has now doubled the number of genes linked to the dementia to 21. The findings, published in the journal Nature Genetics, indicate a strong role for the immune system. Alzheimer's Research UK said the findings could "significantly enhance" understanding of the disease. The number of people developing Alzheimer's is growing around the world as people live longer. However, major questions around what causes the dementia, how brain cells die, how to treat it or even diagnose it remain unanswered. "It is really difficult to treat a disease when you do not understand what causes it," one of the lead researchers, Prof Julie Williams from Cardiff University, said. Detective work The genetic code, the instructions for building and running the body, was scoured for clues. A group - involving nearly three quarters of the world's Alzheimer's geneticists from 145 academic institutions - looked at the DNA of 17,000 patients and 37,000 healthy people. They found versions of 21 genes, or sets of instructions, which made it more likely that a person would develop Alzheimer's disease. They do not guarantee Alzheimer's will develop, but they do make the disease more likely. By looking at the genes' function in the body, it allows researchers to figure out the processes going wrong in Alzheimer's disease. BBC © 2013

Keyword: Alzheimers; Genes & Behavior
Link ID: 18843 - Posted: 10.28.2013

By Janet Davison, CBC News Jason Novick has seen the darkness that mental health disorders can create. The 27-year-old Toronto man has also seen how advocacy — by himself and by others — has been vital in helping him cope with bipolar disorder, general anxiety disorder, mania and depression, particular during the stressful transition from his teenage years to leaving home for post-secondary school. "Mental health awareness … is still an issue that’s largely misunderstood," he said in a recent interview. "There’s a lot of [post-secondary] administrative workers and professors and program co-ordinators and what have you who won’t know the first thing about such issues, so your best ally is probably going to be yourself a lot of the time." Another ally can also be a caring friend or family member who steps up to help others understand the larger situation. Novick remembers going with his mother to "set the record straight" with a college professor. They wanted to explain to the instructor that it was his mental health that was his problem, not any lack of interest in the course. "It was my mental health that was causing me to be so withdrawn, that was causing me to be so unmotivated. I was passionate about the subject, but I was not passionate about life and living." Novick, who says he contemplated suicide at one point and has been in closed hospital wards three times because of his disorders, is much more passionate about life and living now, particularly after having completed an inpatient program at the Centre for Addiction and Mental Health in Toronto. © CBC 2013

Keyword: Depression; Schizophrenia
Link ID: 18842 - Posted: 10.28.2013

by Bethany Brookshire There are many animal species out there that exhibit same-sex mating behavior. This can take the form of courtship behaviors, solicitation, all the way through to mounting and trading off sperm). In some species, it’s clear that some of this behavior is because the animals involved have pair bonded. But what about insects? Many insects mate quickly, a one and done approach, with very little bonding involved beyond what’s needed to protect against other potential suitors. When it comes to bugs, is it intentional same-sex behavior? Or is it all a mistake? Hypotheses are out there, but in the end, we need science. A new study in the November Behavioral Ecology and Sociobiology wants to answer these questions. The authors did a meta-analysis of papers looking at same-sex sexual activity in male insects and arachnids. They tried to tease out why same-sex sexual behavior might occur in insects. What are the benefits? The potential downsides? And from that, to hypothesize why it might occur. Some of it, it turns out, could be due to context. A lot of observed same-sex mating behavior in insects is observed, for example, when the males are all housed together, away from the females. Partially because of this (but possibly for other reasons as well), same-sex sexual behavior in insects tends to occur much more frequently in the lab than in the wild. But it’s still often documented in the field. Why does it happen? Some say that by mating with a “passive” male and transferring sperm, that sperm then gets passed over to the female when the passive male mates. Sneaky. But does it really happen? And if it does, is it effective? So far, it doesn’t appear that it is; less than 0.5% of the offspring resulted from the transfer of sperm when these cases were documented. © Society for Science & the Public 2000 - 2013

Keyword: Sexual Behavior; Evolution
Link ID: 18841 - Posted: 10.28.2013

By ADAM NAGOURNEY and RICK LYMAN LOS ANGELES — In the heart of Northern California’s marijuana growing region, the sheriff’s office is inundated each fall with complaints about the stench of marijuana plots or the latest expropriation of public land by growers. Its tranquil communities have been altered by the emergence of a wealthy class of marijuana entrepreneurs, while nearly 500 miles away in Los Angeles, officials have struggled to regulate an explosion of medical marijuana shops. But at a time when polls show widening public support for legalization — recreational marijuana is about to become legal in Colorado and Washington, and voter initiatives are in the pipeline in at least three other states — California’s 17-year experience as the first state to legalize medical marijuana offers surprising lessons, experts say. Warnings voiced against partial legalization — of civic disorder, increased lawlessness and a drastic rise in other drug use — have proved unfounded. Instead, research suggests both that marijuana has become an alcohol substitute for younger people here and in other states that have legalized medical marijuana, and that while driving under the influence of any intoxicant is dangerous, driving after smoking marijuana is less dangerous than after drinking alcohol. Although marijuana is legal here only for medical use, it is widely available. There is no evidence that its use by teenagers has risen since the 1996 legalization, though it is an open question whether outright legalization would make the drug that much easier for young people to get, and thus contribute to increased use. And though Los Angeles has struggled to regulate marijuana dispensaries, with neighborhoods upset at their sheer number, the threat of unsavory street traffic and the stigma of marijuana shops on the corner, communities that imposed early and strict regulations on their operations have not experienced such disruption. © 2013 The New York Times Company

Keyword: Drug Abuse
Link ID: 18840 - Posted: 10.28.2013

If you were stung by a bark scorpion, the most venomous scorpion in North America, you’d feel something like the intense, painful jolt of being electrocuted. Moments after the creature flips its tail and injects venom into your skin, the intense pain would be joined by a numbness or tingling in the body part that was stung, and you might experience a shortness of breath. The effect of this venom on some people—small children, the elderly or adults with compromised immune systems—can even trigger frothing at the mouth, seizure-like symptoms, paralysis and potentially death. Based solely on its body size, the four-inch-long furry grasshopper mouse should die within minutes of being stung—thanks to the scorpion’s venom, which causes temporary paralysis, the muscles that allow the mouse to breathe should shut down, leading to asphyxiation—so you’d think the rodent would avoid the scorpions at all costs. But if you put a mouse and a scorpion in the same place, the rodent’s reaction is strikingly brazen. If stung, the four-inch-long rodent might jump back for a moment in surprise. Then, after a brief pause, it’ll go in for the kill and devour the scorpion piece by piece: This predatory behavior isn’t the result of remarkable toughness. As scientists recently discovered, the mouse has evolved a particularly useful adaptation: It’s immune to both the pain and paralytic effects that make the scorpion’s venom so toxic. Although scientists long knew that the mouse, native to the deserts of the American Southwest, preys upon a range of non-toxic scorpions, “no one had ever really asked whether they attack and kill really toxic scorpions,” says Ashlee Rowe of Michigan State University, who led the new study published today in Science.

Keyword: Pain & Touch; Evolution
Link ID: 18839 - Posted: 10.28.2013

Who would win in a fight: a bark scorpion or a grasshopper mouse? It seems like an easy call. The bark scorpion (Centruroides sculpturatus) delivers one of the most painful stings in the animal kingdom—human victims have compared the experience to being branded. The 25-gram grasshopper mouse (Onychomys torridus) is, well, a mouse. But as you can see in the video above, grasshopper mice routinely kill and eat bark scorpions, blissfully munching away even as their prey sting them repeatedly (and sometimes right in the face). Now, scientists have discovered why the grasshopper mice don’t react to bark scorpion stings: They simply don’t feel them. Evolutionary neurobiologist Ashlee Rowe at the University of Texas, Austin, has been studying the grasshopper mice’s apparent superpower since she was in graduate school. For the new study, she milked venom from nearly 500 bark scorpions and started experimenting. When she injected the venom into the hind paws of regular laboratory mice, the mice furiously licked the site for several minutes. But when she injected the same venom into grasshopper mice, they licked their paws for just a few seconds and then went about their business, apparently unfazed. In fact, the grasshopper mice appeared to be more irritated by injections of the saline solution Rowe used as a control. Rowe knew that grasshopper mice weren’t entirely impervious to pain—they reacted to injections of other painful chemicals such as formalin, just not the bark scorpion venom. To find out what was going on, she and her team decided to determine how the venom affects the grasshopper mouse’s nervous system, in particular the parts responsible for sensing pain. © 2013 American Association for the Advancement of Science

Keyword: Pain & Touch; Neurotoxins
Link ID: 18838 - Posted: 10.26.2013

By HELENE STAPINSKI IN an office of the American Museum of Natural History, a team of scientists, artists and multimedia experts were discussing what had poisoned Skippy, a cute Jack Russell terrier that had keeled over sick in his virtual backyard. Was it the chocolate he found in the garbage can? Did a snake, or a black widow spider, bite him? Or was a poisonous cane toad to blame? Skippy is just one of many victims in the museum’s show, “The Power of Poison,” opening Nov. 16, to which the staff was busy applying finishing touches. Using iPads, visitors can examine the circumstances surrounding Skippy’s fictional poisoning and, controlling their experience individually, take a crack at solving the mystery. But because the museum is popular with small children, Skippy does not die. Instead, his animated eyes turn into Xs, he runs erratically around the yard, he drools and he vomits a bit. Eventually, though, Skippy rallies to full health. “We were not going to make this a scary show,” said the exhibit’s curator, Dr. Mark Siddall. “Instead you walk out saying, ‘Wow. That was cool.’ ” Dr. Siddall spent two hours enthusiastically discussing poison and its properties at the museum recently, walking through some of the show’s highlights. The exhibit, which takes a look at poison’s role in nature, myth, medicine and human history, examines killer caterpillars, zombie ants and deadly vipers. It also looks at the possible victims, like the heavily slumbering Snow White. Plus the age-old question of what killed Cleopatra. Was it an asp, or something else? And while we’re at it, was Napoleon really poisoned with arsenic? © 2013 The New York Times Company

Keyword: Neurotoxins
Link ID: 18837 - Posted: 10.26.2013

by Linda Geddes Anaesthetics usually knock you out like a light. But by slowing the process down so that it takes 45 minutes to become totally unresponsive, researchers have discovered a new signature for unconsciousness. The discovery could lead to more personalised methods for administering anaesthetics and cut the risks associated with being given too high or too low a dose. It also sheds new light on what happens to our brain when we go under the knife. Hundreds of thousands of people are anaesthetised every day, yet researchers still don't fully understand what's going on in the anaesthetised brain. Nor is there a direct way of measuring when someone is truly unresponsive. Instead, anaesthetists rely on indirect measures such as heart and breathing rate, and monitoring reflexes. To investigate further, Irene Tracey and her colleagues at Oxford University slowed the anaesthesia process down. Instead of injecting the anaesthetic propofol in one go, which triggers unconsciousness in seconds, the drug was administered gradually so that it took 45 minutes for 16 volunteers to become fully anaesthetised. Their brain activity was monitored throughout using electroencephalography (EEG). The study was then repeated on 12 of these volunteers using functional magnetic resonance imaging (fMRI). EEG recordings revealed that before the volunteers became completely unresponsive to external stimuli they progressed through a sleep-like state characterised by slow-wave oscillations – a hallmark of normal sleep, in which neurons cycle between activity and inactivity. As the dose of anaesthetic built up, more and more neurons fell into this pattern, until a plateau was reached when no more neurons were recruited, regardless of the dose administered. © Copyright Reed Business Information Ltd.

Keyword: Consciousness; Sleep
Link ID: 18836 - Posted: 10.26.2013