Chapter 16. None
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By ABIGAIL ZUGER, M.D. One legend says it all began when a North African herder saw his goats eat some wild berries, then frolic with unusual verve. Another story cites a few small leaves blown off a nearby bush into the Chinese emperor’s mug of hot water. Either way, whether caffeine entered the life of man by coffee bean or tea leaf, happiness ensued. Happiness, that is, for all but the poor souls charged with saving us from our drugs, for no regulatory challenge trumps the one posed by caffeine, molecule of elegant enjoyment and increasing abuse, man’s best friend and occasional killer. As Murray Carpenter makes clear in his methodical review, our society’s metrics are no match for this substance’s nuances, whether among athletes, teenagers, experimental subjects or the average dependent Joe. (Read an excerpt of “Caffeinated.”) Pure caffeine is a bitter white powder. In the body it blocks the effects of the molecule adenosine, a crucial brake on many physiologic processes. With just enough caffeine in the system, the body’s organs become a little more themselves: the brain a little brainier, the muscles a little springier, the blood vessels a little tighter, the digestion a little more efficient. With too much caffeine, all can accelerate into cardiac arrest. It takes only about 30 milligrams of caffeine (less than a cup of coffee or can of cola) for stimulative effects to be noticeable. A hundred milligrams a day will hook most people: They feel immensely unhappy without their daily fix, and the organs all whine in protest for a few days. It takes more than 10 grams to kill you — a dose impossible to achieve with traditional beverages alone. However, the new caffeine-rich energy shots make it alarmingly easy for party-minded people to achieve the zone between enough and much too much. © 2014 The New York Times Company
Keyword: Drug Abuse
Link ID: 19427 - Posted: 03.31.2014
By BRAYDEN KING and JERRY KIM THIS season Major League Baseball is allowing its officiating crews to use instant replay to review certain critical calls, including home runs, force plays and foul balls. But the calling of the strike zone — determining whether a pitch that is not swung at is a ball or a strike — will still be left completely to the discretion of the officials. This might seem an odd exception, since calling the strike zone may be the type of officiating decision most subject to human foible. In research soon to be published in the journal Management Science, we studied umpires’ strike-zone calls using pitch-location data compiled by the high-speed cameras introduced by Major League Baseball several years ago in an effort to measure, monitor and reward umpires’ accuracy. After analyzing more than 700,000 pitches thrown during the 2008 and 2009 seasons, we found that umpires frequently made errors behind the plate — about 14 percent of non-swinging pitches were called erroneously. Some of those errors occurred in fairly predictable ways. We found, for example, that umpires tended to favor the home team by expanding the strike zone, calling a strike when the pitch was actually a ball 13.3 percent of the time for home team pitchers versus 12.7 percent of the time for visitors. Other errors were more surprising. Contrary to the expectation (or hope) that umpires would be more accurate in important situations, we found that they were, in fact, more likely to make mistakes when the game was on the line. For example, our analyses suggest that umpires were 13 percent more likely to miss an actual strike in the bottom of the ninth inning of a tie game than in the top of the first inning, on the first pitch. © 2014 The New York Times Company
Link ID: 19426 - Posted: 03.31.2014
by Laura Sanders Ever-increasing numbers of autism diagnoses have parents worried about a skyrocketing epidemic, and this week’s news may only drive alarm higher. Perhaps it shouldn’t. In 2010, 1 in 68 (or 14.7 per 1,000) 8-year-olds had an autism spectrum disorder, the Centers for Disease Control and Prevention now estimates. That number is a substantial increase from 2008, which had an estimate of 1 in 88 (or 11.3 per 1,000). But the numbers might not reflect a spike in actual cases. Instead, the rise might be driven, at least in part, by an increase in diagnoses. The estimates are drawn from a collection of organizations that provide services to children with autism, including doctors, schools and social service agencies. As awareness builds and more people look for signs of autism, these numbers will keep going up. Regional spottiness suggests that better autism detection is feeding the increase. The autism rate in Alabama is just one in 175, while the rate in New Jersey is one in 45, the CDC reports. It would be surprising, and scientifically really important, if children in Alabama were truly much more protected from the disorder. Instead, differences in diagnosis rates are probably at play. If these alarmingly high numbers are driven by professionals and parents better spotting autism, that’s nothing to be alarmed at. On the contrary: This is good news. The earlier therapies begin, the better kids with autism do. That’s the idea behind CDC’s “Learn the Signs: Act Early” program to educate people about signs that something might be amiss with a child. So our best move is to find the kids who need help, and find them when they’re young. Most kids, including the ones in the new CDC survey, aren’t diagnosed with autism until about age 4 1/2. But whatever goes wrong happens long before then. © Society for Science & the Public 2000 - 2013.
Link ID: 19424 - Posted: 03.29.2014
By Lenny Bernstein After 60 years of refusing, the people who run the Golden Gate Bridge are moving toward installing a suicide barrier, the New York Times reports. As soon as May, the Golden Gate Bridge, Highway and Transportation District is expected to approve construction of a steel mesh net 20 feet below the California landmark’s sidewalk. A record 46 people jumped to their deaths from the span in 2013, and another 118 were stopped before they could. According to the Times, they have tended to be younger than in the past. Experts have long known, and good research shows, that barriers are highly effective at halting suicides, the 10th-leading cause of death in the United States at 38,364 fatalities in 2010. This is true not just of bridges or other high places: locking up firearms and individually bubble-wrapping pills both limit suicides by those methods, said Jill Harkavy-Friedman, vice president of research for the American Foundation for Suicide Prevention. The key is the characteristics of a person on the verge of committing suicide, even someone who has been contemplating it for a while. Suicides are impulsive acts, and the people who commit them are not thinking clearly, have trouble solving problems, have difficulty shifting gears and weigh risks differently. If thwarted in that first, impulsive attempt, they often do not adjust and seek another way to take their lives, Harkavy-Friedman said. “In a suicidal crisis, it’s all about time,” she said. “They’re going to grab whatever is available. They don’t change gears if that is thwarted, because they have rigid thinking in that moment. They’re not thinking about dying. They’re thinking about ending the pain. © 1996-2014 The Washington Post
Link ID: 19423 - Posted: 03.29.2014
By SINDYA N. BHANOO Monogamy is rare in animals. Even among species that pair off, there is often philandering. But a new genetic analysis adds to the evidence that the South American primates called Azara’s owl monkeys are remarkably faithful to their partners. The study confirms what one of its authors, Eduardo Fernandez-Duque, an evolutionary anthropologist at the University of Pennsylvania who leads the Owl Monkey Project, had long suspected. For 18 years, he and other Penn researchers have been observing the Azara’s owl monkey in the Chaco region of Argentina. Not only have they never witnessed a philanderer, but they have also found that infant owl monkeys get an unusual amount of care from their fathers. “The male plays with the infant and the male shares food with the infant even more than the mother,” Dr. Fernandez-Duque said. “The males care because these are their offspring, and this has a direct benefit in terms of reproductive success.” In the new study, published in the Proceedings of the Royal Society B, the researchers performed genetic analysis on 35 offspring born to 17 owl monkey pairs and confirmed that the parents were monogamous for the mating season. The monkey is the first primate and only the fifth mammal for which monogamy has been verified through genetics. Because paternal care is also seen in other species of owl monkeys, the scientists suspect that they, too, are serially monogamous. © 2014 The New York Times Company
Nicola Davis The moment when 40-year old Joanne Milne, who has been deaf since birth, first hears sound is heart-wrenching scene. Amateur footage showing her emotional reaction has taken social media by storm and touched viewers across the world, reinforcing the technological triumph of cochlear implants. It’s a story I have touched on before. Earlier this month I wrote about how cochlear implants changed the lives of the Campbells whose children Alice and Oliver were born with the condition auditory neuropathy spectrum disorder (ANSD). Implants, together with auditory verbal therapy, have allowed them to embrace the hearing world. It was incredibly moving to glimpse the long and difficult journey this family had experienced, and the joy that hearing - a sense so many of us take for granted - can bring. Cochlear implants are not a ‘cure’ for deafness. They make use of electrodes to directly stimulate auditory nerve fibres in the cochlea of the inner ear, creating a sense of sound that is not the same as that which hearing people experience, but nevertheless allows users to perceive speech, develop language and often enjoy music. As an adult Milne, who was born with the rare condition Usher syndrome, is unusual in receiving cochlear implants on both sides. Such bilateral implantation enables users to work out where sounds are coming from, enhances speech perception in bustling environments and means that should something go wrong with one device, the user isn’t cut off from the hearing world. © 2014 Guardian News
By Helen Briggs BBC News When it comes to detecting lies, you should trust your instinct, research suggests. We are better at identifying liars when we rely on initial responses rather than thinking about it, say psychologists. Generally we are poor at spotting liars - managing only slightly better than flipping a coin. But our success rate rises when we harness the unconscious mind, according to a report in Psychological Science. "What interested us about the unconscious mind is that it just might really be the seat of where accurate lie detection lives," said Dr Leanne ten Brinke of the University of California, Berkeley. "So if our ability to detect lies is not conscious - we simply can't do this when we're thinking hard about it - then maybe it lives somewhere else, and so we thought one possible explanation was the unconscious mind." When trying to find out if someone is lying, most people rely on cues like someone averting their gaze or appearing nervous. However, research suggests this is not accurate - people perform at only about 50% accuracy in traditional lie detection tasks. Psychologists at the University of California were puzzled by this, as some primates, such as chimps, are able to detect deceit - and evolutionary theory supposes that it maximises survival and reproductive success. Dr Ten Brinke and colleagues devised experiments to test the ability of the unconscious mind to spot a liar, to see if they could do better than the conscious mind. BBC © 2014
Link ID: 19420 - Posted: 03.29.2014
by Hal Hodson Software has performed the first real-time translation of a dolphin whistle – and better data tools are giving fresh insights into primate communication too IT was late August 2013 and Denise Herzing was swimming in the Caribbean. The dolphin pod she had been tracking for the past 25 years was playing around her boat. Suddenly, she heard one of them say, "Sargassum". "I was like whoa! We have a match. I was stunned," says Herzing, who is the director of the Wild Dolphin Project. She was wearing a prototype dolphin translator called Cetacean Hearing and Telemetry (CHAT) and it had just translated a live dolphin whistle for the first time. It detected a whistle for sargassum, or seaweed, which she and her team had invented to use when playing with the dolphin pod. They hoped the dolphins would adopt the whistles, which are easy to distinguish from their own natural whistles – and they were not disappointed. When the computer picked up the sargassum whistle, Herzing heard her own recorded voice saying the word into her ear. As well as boosting our understanding of animal behaviour, the moment hints at the potential for using algorithms to analyse any activity where information is transmitted – including our daily activities (see "Scripts for life"). "It sounds like a fabulous observation, one you almost have to resist speculating on. It's provocative," says Michael Coen, a biostatistician at the University of Wisconsin-Madison. © Copyright Reed Business Information Ltd.
Ewen Callaway An equine oddity with the head of a zebra and the rump of a donkey, the last quagga (Equus quagga quagga) died in 1883. A century later, researchers published1 around 200 nucleotides sequenced from a 140-year-old piece of quagga muscle. Those scraps of DNA — the first genetic secrets pulled from a long-dead organism — revealed that the quagga was distinct from the mountain zebra (Equus zebra). More significantly, the research showed that from then on, examining fossils would no longer be the only way to probe extinct life. “If the long-term survival of DNA proves to be a general phenomenon,” geneticists Russell Higuchi and Allan Wilson of the University of California, Berkeley, and their colleagues noted in their quagga paper1, “several fields including palaeontology, evolutionary biology, archaeology and forensic science may benefit.” At first, progress was fitful. Concerns over the authenticity of ancient-DNA research fuelled schisms in the field and deep scepticism outside it. But this has faded, thanks to laboratory rigour that borders on paranoia and sequencing techniques that help researchers to identify and exclude contaminating modern DNA. These advances have fostered an ancient-genomics boom. In the past year, researchers have unveiled the two oldest genomes on record: those of a horse that had been buried in Canadian permafrost for around 700,000 years2, and of a roughly 400,000-year-old human relative from a Spanish cavern3. A Neanderthal sequence every bit as complete and accurate as a contemporary human genome has been released4, as has the genome of a Siberian child connecting Native Americans to Europeans5. © 2014 Nature Publishing Group
By Greg Miller Nobody knows what causes autism, a condition that varies so widely in severity that some people on the spectrum achieve enviable fame and success while others require lifelong assistance due to severe problems with communication, cognition, and behavior. Scientists have found countless clues, but so far they don’t quite add up. The genetics is complicated. The neuroscience is conflicted. Now, a new study adds an intriguing, unexpected, and sure-to-be controversial finding to the mix: It suggests the brains of children with autism contain small patches where the normally ordered arrangement of neurons in the cerebral cortex is disrupted. “We’ve found locations where there appears to be a failure of normal development,” said Eric Courchesne, a neuroscientist at the University of California, San Diego and an author of the study, which appears today in the New England Journal of Medicine. “It’s been really difficult to identify a lesion or anything in the brain that’s specific and diagnostic of autism,” said Thomas Insel, director of the National Institute of Mental Health, one of several agencies that funded the project. The new study is notable because it applies sophisticated molecular labeling methods to postmortem tissue from people with autism who died as children, which is incredibly hard to come by, Insel says. “If it’s real, if it’s replicated and it’s a consistent finding, it’s more evidence that autism starts prenatally and only manifests itself when kids start to have trouble with language or social behavior around age two or three,” Insel said. “These kinds of changes in cellular architecture would happen during brain development, probably around the first part of the second trimester.” © 2014 Condé Nast
by Erika Engelhaupt What gets us hot can be so revealing. For me, the slightest anxiety or excitement can trigger a warm spread across my face. I can feel the blood rushing up my neck and into the thousands of tiny capillaries across my cheeks. I’ve worn scarves or turtlenecks to job interviews, weather be damned, to keep my burning red neck from betraying my nerves. And the opposite can be true. Have you ever seen someone truly blanch? Given a real fright, the blood can literally drain from a person’s face, leaving a white mask. This all happens thanks to the autonomic nervous system, the fight-or-flight control system. Faced with danger, it tells blood vessels to pinch off the flow to the face and extremities, sending more blood to the muscles and body core so you’ll be pumped up for either the flight or the fight. Heat-sensing cameras can pick all this up, and in way more detail than my scarf could hide. Our nervous systems are constantly chugging away, largely out of our conscious control, tweaking our blood flow for every emotion. Just think of all the tiny wafts of heat flowing across your face as you negotiate with your boss, or talk to your lover. Feeling a bit anxious? Guilty? Stressed? Sexually aroused, perhaps? There’s a researcher out there with a thermal camera that can detect each of those. Even post-traumatic stress disorder may show up in your face’s heat map. In a pilot study of bank tellers who have been robbed, a team of researchers in Italy reports in the April 25 Neuroscience that tellers with mild PTSD have amped-up fear responses that show up in their facial heat signature. © Society for Science & the Public 2000 - 2013.
Matt Wall Given the media coverage brain imaging studies get, you might think that they are constantly revealing important secrets about this mysterious organ. Catherine Loveday thinks otherwise. She makes the point that using brain-scanning technology to understand what a diseased brain is doing is only of academic interest. It is the study of the mind through behaviour and other cognitive functions, she argues, that leads to useful insights about disorders and treatments. There is some truth here, but as a scientist who uses brain scans every day, I would argue that they contribute a lot more than Loveday gives them credit for. The main problem is that, when it comes to the brain, all analogies are hopelessly crude. The distinction between hardware and software – or the brain and the mind – only has limited practical usefulness. Since all mental processes arise as a result of brain processes, it follows that all mental problems are also a result of dysfunctions in the physical brain. This will be seen by many as an extreme and reductionist position, but a specific example should help to show that it has some value. Parkinson’s disease is a degenerative disorder that causes a variety of symptoms including motor problems, sleep disturbance, various cognitive issues, and often depression. This variety of symptoms might suggest that the underlying problem in Parkinson’s is quite broad and complex, affecting several brain systems. However, it turns out the cause of all these symptoms is quite specific: a loss of neurons in a region of the brain called the substantia nigra. © 2014 Guardian News and Media Limited
Keyword: Brain imaging
Link ID: 19414 - Posted: 03.27.2014
by Aviva Rutkin Eureka! Like Archimedes in his bath, crows know how to displace water, showing that Aesop's fable The Crow and the Pitcher isn't purely fictional. To see if New Caledonian crows could handle some of the basic principles of volume displacement, Sarah Jelbert at the University of Auckland in New Zealand and her colleagues placed scraps of meat just out of a crow's reach, floating in a series of tubes that were part-filled with water. Objects potentially useful for bringing up the water level, like stones or heavy rubber erasers, were left nearby. The crows successfully figured out that heavy and solid objects would help them get a treat faster. They also preferred to drop objects in tubes where they could access a reward more easily, picking out tubes with higher water levels and choosing tubes of water over sand-filled ones. However, the crows failed at more challenging tasks that required an understanding of the effect of tube width or the ability to infer a hidden connection between two linked tubes. The crows displayed reasoning skills equivalent to an average 5 to 7 year old human child, the researchers claim. Previously, Eurasian jays have shown some understanding of water displacement, as have chimpanzees and orang-utans, but using similar experiments could assess and compare their skill levels. "Any animal capable of picking up stones could potentially participate," write the researchers. © Copyright Reed Business Information Ltd.
by Colin Barras What a nerve! Skin cells taken from people with bipolar disorder have been turned into brain cells. These in turn are offering up clues about the changes in the brain that drive the disorder, and may also provide a way to test new treatments. About three in every 100 people develop bipolar disorder – a mental illness characterised by episodes of depression and euphoria. But the condition remains poorly understood. That's because it would be too invasive to obtain and study viable nerve cells from the brains of people with the condition. There are also no good animal models, because bipolar disorder – although highly heritable – has, for the most part, not been linked to any specific genes that can be studied using animals. "People say the condition is probably the result of a lot of small contributions by multiple genes," says Sue O'Shea at the University of Michigan in Ann Arbor. Now O'Shea and her colleagues may have found an ethical way to make a genetic model of the condition. First, they took skin samples from 22 people with bipolar disorder and 10 healthy volunteers. They induced these adult skin cells to return to a stem-cell-like state, creating what are called induced pluripotent stem cells (iPSCs) and then encouraged these cells to mature into neurons. O'Shea was surprised to find that neurons derived from people with bipolar disorder grew differently from those from people without the condition. "I was expecting it would take decades of careful science before we would find any real differences," she says. © Copyright Reed Business Information Ltd.
By RICHARD A. FRIEDMAN FEELING down? Smile. Cheer up. Put on a happy face. No doubt you’ve dismissed these bromides from friends and loved ones because everyone knows that you can’t feel better just by aping a happy look. Or perhaps you can. New research suggests that it is possible to treat depression by paralyzing key facial muscles with Botox, which prevents patients from frowning and having unhappy-looking faces. In a study forthcoming in the Journal of Psychiatric Research, Eric Finzi, a cosmetic dermatologist, and Norman Rosenthal, a professor of psychiatry at Georgetown Medical School, randomly assigned a group of 74 patients with major depression to receive either Botox or saline injections in the forehead muscles whose contraction makes it possible to frown. Six weeks after the injection, 52 percent of the subjects who got Botox showed relief from depression, compared with only 15 percent of those who received the saline placebo. (You might think that patients would easily be able to tell whether they got the placebo or Botox. Actually, it wasn’t so obvious: Only about half of the subjects getting Botox guessed correctly. More important, knowing which treatment was received had no significant effect on treatment response.) Other studies over the past several years have found similar effects of Botox on mood. Michael Lewis at Cardiff University reported that nondepressed patients at a cosmetic dermatology clinic receiving Botox injection above the eyes frowned less and felt better than those who did not receive this injection. And M. Axel Wollmer at the University of Basel found that Botox injection was superior to a placebo in a group of depressed patients. © 2014 The New York Times Company
Link ID: 19410 - Posted: 03.26.2014
By Jennifer Richler A few days ago, an old friend sent me a panicked email. She had just finished reading Ron Suskind’s beautiful essay in the New York Times Magazine about raising a son with autism: “Reaching My Autistic Son Through Disney.” Suskind describes how, at almost 3 years of age, his son Owen “disappeared.” The child was once “engaged, chatty, full of typical speech,” but then he stopped talking, lost eye contact, even struggled to use a sippy cup. Owen was eventually diagnosed with a regressive form of autism, which Suskind says affects about a third of children with the disorder. “Unlike the kids born with it,” he continues, “this group seems typical until somewhere between 18 and 36 months—then they vanish.” That was the line that alarmed my friend, whose son is nearing his third birthday. “What is this ‘regressive autism?’ ” she asked me, the resident autism expert in her peer group. (I conducted research on autism and regression in autism before becoming a freelance writer.) “I thought we were out of the woods!” I’m sure many parents of young children who read the piece had the same reaction, and it’s completely understandable. It’s also unwarranted. The claim that many kids with autism develop typically for almost three years and then experience a near-complete loss of language, social skills, and motor ability—a claim I’ve read many times before—simply isn’t true. It’s time to set the record straight. © 2014 The Slate Group LLC.
Link ID: 19409 - Posted: 03.26.2014
Andreas von Bubnoff People who are unable to recognize faces can still learn to distinguish between other types of very similar objects, researchers report. The finding provides fresh support for the idea that the brain mechanisms that process face images are specialized for that task. It also offers evidence against an 'expertise' hypothesis, in which the same mechanisms are responsible for recognition of faces and other highly similar objects we have learned to tell apart — the way bird watchers can recognize birds after years of training. Constantin Rezlescu, a psychologist at Harvard University in Cambridge, Massachusetts, and his colleagues worked with two volunteers nicknamed Florence and Herschel, who had acquired prosopagnosia, or face blindness, following brain damage. The condition renders people unable to recognize and distinguish between faces — in some cases, even those of their own family members. The team trained Florence and Herschel to recognize greebles, computer-generated objects that differ from one another in similar ways to faces. The two volunteers spent eight training sessions of up to one hour learning to recognize 20 different greebles. The objects belonged to five different ‘families’ that were easier to distinguish between than were the individual greebles, and initially the participants took longer to discriminate individual greebles within the same family than they did the different families. But by the end of the training, they could tell individual greebles apart just as quickly — a sign that they had become experts in recognizing them, just as dog trainers can recognize individual dogs as easily as different breeds of dog. The study appears in Proceedings of the National Academy of Sciences1. © 2014 Nature Publishing Group
Link ID: 19408 - Posted: 03.25.2014
By CATHERINE SAINT LOUIS ALEXANDRIA, N.H. — For most of his life, Kevin Ramsey has lived with epileptic seizures that drugs cannot control. At least once a month, he would collapse, unconscious and shaking violently, sometimes injuring himself. Nighttime seizures left him exhausted at dawn, his tongue a bloody mess. After episodes at work, he struggled to stay employed. Driving became too risky. At 28, he sold his truck and moved into his mother’s spare bedroom. Cases of intractable epilepsy rarely have happy endings, but today Mr. Ramsey is seizure-free. A novel battery-powered device implanted in his skull, its wires threaded into his brain, tracks its electrical activity and quells impending seizures. At night, he holds a sort of wand to his head and downloads brain data from the device to a laptop for his doctors to review. “I’m still having seizures on the inside, but my stimulator is stopping all of them,” said Mr. Ramsey, 36, whose hands shake because of one of the three anti-seizure drugs he still must take. “I can do things on my own I couldn’t do before. I can go to the store on my own, and get my groceries. Before, I wouldn’t have been able to drive.” Just approved by the Food and Drug Administration, the long-awaited device, called the RNS System, aims to reduce seizures and to improve the lives of an estimated 400,000 Americans whose epilepsy cannot be treated with drugs or brain surgery. “This is the first in what I believe is a new generation of therapy for epilepsy,” said Dr. Dileep R. Nair, head of adult epilepsy at the Cleveland Clinic and an investigator in the pivotal trial for NeuroPace’s RNS. “It’s delivering local therapy. It’s not taking tissue out; the brain is left intact. And it’s unlike a drug, which is a shotgun approach.” © 2014 The New York Times Company
Link ID: 19407 - Posted: 03.25.2014
Dragonflies are full of surprises. They have six legs, but most can’t walk. Their giant, 30,000-lens eyes can detect ultraviolet light. And though they lack the brain architecture normally required for a sense of smell, a new study finds that dragonflies may use odors to hunt prey. Smelling, as we humans understand it, requires certain hardware. Our noses are packed with olfactory receptors, each of which is tuned to a precise scent molecule. (Indeed, a recent study suggests we can detect a trillion smells.) When one wafts into our nostrils, these receptors send nerve signals to sensory way stations called glomeruli, which pass them along to the brain for interpretation—“Oh, a rose!” Glomeruli are shared by most terrestrial mammals and insects, and until now, scientists believed they represented the only possible route to a sense of smell. Because dragonflies and their close cousins, damselflies, don’t possess glomeruli or any higher order smell centers in their brains, most scientists believed these insects were unable to smell anything at all. Invertebrate biologist Manuela Rebora at the University of Perugia in Italy was not one of them. When her team took a closer look at dragonfly and damselfly antennae with an electron microscope, they spotted tiny bulbs in pits that resembled olfactory sensilla. Like the insect equivalent of a nose, these sensilla house olfactory neurons. When Rebora’s team exposed the suspected sensilla to scents, they emitted nerve pulses, supporting the idea that damselflies and dragonflies perceive odors. © 2014 American Association for the Advancement of Science.
Keyword: Chemical Senses (Smell & Taste)
Link ID: 19406 - Posted: 03.25.2014
Daniel Cressey The controversy over electronic cigarettes has been reignited today with the publication of a study claiming that they do not help smokers to quit their habit. Whether or not ‘e-cigarettes’ are an effective aid in the cessation of smoking has become a major issue for the rapidly growing industry that produces the devices, and for the tobacco researchers struggling to assess their impact. There is widespread agreement that inhaling from an e-cigarette, where a heating element vapourizes a liquid containing nicotine, is not as harmful as smoking a conventional cigarette, and proponents say that the products could save millions of lives. But some researchers and tobacco-control activists fear that the devices could make tobacco use seem socially acceptable again and may not assist people in actually reducing their addiction. Pamela Ling, a tobacco researcher at the University of California, San Francisco, and her colleagues followed 949 people who detailed their smoking habits though an online survey, and found that 88 of those who had used e-cigarettes were no more likely to have quit or reduced their smoking after a year than other smokers. “We found that there was no difference in the rate of quitting between smokers who used an e-cigarette and those who did not”, even after controlling for factors such as the user's dependence on tobacco, Ling told Nature in an e-mail. She added: “Advertising suggesting that e-cigarettes are effective for smoking cessation should be prohibited until such claims are supported by scientific evidence.” Her team reports the results today in JAMA Internal Medicine1. © 2014 Nature Publishing Group
Keyword: Drug Abuse
Link ID: 19405 - Posted: 03.25.2014