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By Scicurious “That’s not FAIR!” This is the line that rings through most houses with at least one kid. We all know when something’s not fair. That car that drove up the shoulder while you waited in traffic (rrrrr)? That’s a cheater, and that’s not fair. The person who cut in line at the grocery store instead of waiting? That’s not fair either. We get a sense of what is fair or unfair at a pretty young age, and we also understand that we are allowed, and indeed encouraged in some cases, to punish unfair behavior. But we don’t all punish unfair behavior the same way, especially when punishment may be detrimental to us. What is responsible for this difference? What mediates our reactions to what is unfair? The authors of this study think it might be serotonin, and that it may have as much to do with honesty as it does with a sense of what is fair. The basis for this paper was a game used in psychology testing, a very common game called the “Ultimatum game”. In this game, you play against one other player (or, often, against a computer). That other player has found some money, say $10. They want to divide the money with you, and you can choose whether you accept their offer, or reject the offer of splitting the money. For example, if they offer to split 50-50, you may take that offer and the $5, while if they offer to split 90-10, you may be insulted and reject it. © 2012 Scientific American,
Keyword: Emotions; Genes & Behavior
Link ID: 16562 - Posted: 03.22.2012
Graham Lawton, deputy magazine editor FOR such a big topic this is an awfully short book. But don't blame neuroscientist Sam Harris for being brief. He had no choice. In a brisk 66 pages Harris explains why we don't have free will, points out why that doesn't matter as much as it might appear to - and then simply stops in order to hammer home his point. Free will touches everything we value - law, politics, relationships, morality and more. And yet it is an illusion. We either live in a deterministic universe where the future is set, or an indeterminate one where thoughts and actions happen at random. Neither is compatible with free will. Having laid this out, Harris tries to salvage something from the wreckage. In the process he ends up rowing back to a position not unlike the "compatibilists" who argue that free will can be reconciled with the laws of physics, a notion he has earlier attacked. Harris starts his rescue mission by pointing out that, even in the absence of free will, there is still a distinction between voluntary action and mere accidents. Imagine, he says, that while he is writing his book somebody outside fires up a leaf blower. He ignores the sound by attending to his work. The decision feels like the exercise of free will, but isn't. © Copyright Reed Business Information Ltd.
Keyword: Attention; Consciousness
Link ID: 16561 - Posted: 03.22.2012
By Brian Vastag So-called atypical antipsychotic drugs have been blockbusters for the drug industry, pulling in $16 billion in 2010. Developed to treat schizophrenia and related disorders, physicians also prescribe these drugs “off label” for bipolar disorder, insomnia, and other problems the drugs are not approved to treat, as Sandra Boodman wrote in the Post on March 12. But a new report finds that psychiatrists have not been given a full picture of these drugs, which include big sellers like Abilify (aripiprazole), Zyprexa (olanzapine), Risperdal (risperidone), and Seroquel (quetiapine). When seeking approval for eight atypical antipsychotic drugs, drug companies performed 24 studies, according to a Food and Drug Administration database. But four of the studies were never published in professional journals — and all four were unflattering for the drug in question. Three of the unpublished studies showed that the new drug did not perform better than a sugar pill. The fourth study showed that while the antipsychotic drug helped patients more than a placebo, older, less expensive drugs helped patients even more. “That’s bad if you’re marketing the drug,” said Erick Turner, the psychiatrist at Oregon Health & Science University who conducted the new analysis, which was published Tuesday in the journal PLoS Medicine . © 1996-2012 The Washington Post
Keyword: Schizophrenia
Link ID: 16560 - Posted: 03.22.2012
By Alan Boyle Software billionaire Paul Allen is pledging $300 million to establish a series of "brain observatories" at the Seattle research facility named after him, with the aim of mapping and manipulating the mouse brain. The project's leaders say the insights gained could be applied as well to higher forms of life, including humans. "We believe that this project has the potential to revolutionize our understanding of the mammalian brain," Christoph Koch, chief scientific officer for the Allen Institute for Brain Science, and Harvard neuroscientist R. Clay Reid said in the journal Nature. Details about the brain observatory project were laid out today at the Allen Institute in Seattle. In an advance interview, Koch cast the effort in terms usually reserved for the multibillion-dollar Hubble Space Telescope project or the $10 billion Large Hadron Collider. "We're focusing a huge amount of resources on trying to understand this piece of highly, highly complex math and science. The most organized piece of matter in the known universe is the cerebral cortex, the one that makes you and me think and smell and hear and talk. That's what we're trying to understand," Koch told me. "Just as people spend a huge amount of time and effort to build these different observatories to look at the origin of space and time, we're going to build these observatories, these very sophisticated instruments, all of them using common standards, all peering at the brain — primarily animal brains, but also the human brain." © 2012 msnbc.com
Keyword: Brain imaging
Link ID: 16559 - Posted: 03.22.2012
Scientists are now one step closer to developing anti-addiction medications, thanks to new research that provides a better understanding of the properties of the only member of the opioid receptor family whose activation counteracts the rewarding effects of addictive drugs. The study was supported by the National Institute on Drug Abuse (NIDA), the National Institute of General Medical Sciences and the National Institute of Mental Health, all components of the National Institutes of Health. Unlike the other opioid receptor subtypes, the kappa opioid receptor (KOR) is not associated with the development of physical dependence or the abuse potential of opiate drugs (e.g., heroin, morphine). Therefore, medications that act at the KOR could have broad therapeutic potential for addressing addiction, pain, as well as other mental disorders. The leading compound in this context is JDTic because its specific binding to the KOR has been shown to reduce relapse to cocaine seeking in animal models. JDTic is currently in clinical trials to assess its safety and tolerability in humans. In this new study, scientists produced a high resolution three-dimensional image of JDTic bound to the human KOR. By mapping all the points of contact between JDTic and the human KOR, researchers were able to see how the two fit together. The emerging picture reveals critical new information that helps explain why JDTic binds so tightly and specifically to this particular opioid receptor. This advance opens the door to the development of compounds targeting the KOR with improved therapeutic profiles, including that of non-addictive pain medications. The study by Wu et al., can be found at: www.nature.com. For information on prescription drug abuse, go to: www.drugabuse.gov/drugs-abuse/prescription-medications.
Keyword: Drug Abuse; Pain & Touch
Link ID: 16558 - Posted: 03.22.2012
By Devin Powell Proteins turned on by opium and similar substances in the body have now been caught in action. Two new snapshots show how cellular proteins lasso molecules in the opium family, revealing the 3-D structure of such pairings for the first time. The work represents a major step toward designing more specific analgesics and other drugs that lack opioids’ nasty side effects, two teams of researchers report online March 21 in Nature. “Both are landmark studies,” says Gavril Pasternak, a neuroscientist who designs opioids at the Sloan-Kettering Institute in New York City, and who wasn’t involved in either study. “These structures will quickly be utilized with goal of developing nonaddicting painkillers and new ways to combat drug abuse.” Proteins that respond to opium and opiumlike molecules protrude from the surfaces of cells throughout the brain, spinal cord and gut. The body’s own hormones and brain chemicals such as endorphins can bind to these proteins to turn the molecular switches on and off to control pain, regulate breathing and change mood. Many of today’s most powerful painkillers work by switching on one of these proteins, called the mu opioid receptor. But the relief this provides comes at a price. Derivatives of opium, such as morphine and codeine, are addictive and can cause breathing problems and constipation. © Society for Science & the Public 2000 - 2012
Keyword: Pain & Touch; Drug Abuse
Link ID: 16557 - Posted: 03.22.2012
Being overweight in later life puts you at higher risk of brain decline, Korean research suggests. A study of 250 people aged between 60 and 70 found those with a high body mass index (BMI) and big waists scored more poorly in cognitive tests. The Alzheimer's Society said the research, in the journal Age and Ageing, added to evidence that excess body fat can affect brain function. Lifestyle changes can help make a difference, it said. The study looked at the relationship between fat levels and cognitive performance in adults aged 60 or over. The participants underwent BMI - a calculation based on a ratio of weight to height - and waist circumference measurements, a scan of fat stored in the abdomen and a mental test. Both a high BMI and high levels of abdominal fat were linked with poor cognitive performance in adults aged between 60 and 70. In individuals aged 70 and older, high BMI, waist circumference and abdominal body fat were not associated with low cognitive performance. The lead author of the study, Dae Hyun Yoon, said: "Our findings have important public health implications. The prevention of obesity, particularly central obesity, might be important for the prevention of cognitive decline or dementia." BBC © 2012
Keyword: Obesity; Alzheimers
Link ID: 16556 - Posted: 03.22.2012
By Deborah Kotz, Globe Staff Another disappointing clinical trial found that over-the-counter dietary supplements work no better than placebos at halting the detrimental effects of Alzheimer’s disease. This time, the supplements tested were antioxidants -- vitamin E, vitamin C, the omega-3 fatty acid ALA, and coenzyme Q. The same research group determined in a study published 18 months ago that fish oil supplements didn’t stop the progresson of Alzheimer’s either. The current study, published Monday in the Archives of Neurology, was small but well designed, randomly assigning two different combinations of daily antioxidants or placebos to some 60 patients with mild to moderate Alzheimer’s disease for nearly four months. At the end of the study, samples of spinal fluid collected from the patients at the beginning and end of the study showed no change in levels of markers associated with Alzheimer’s, including amyloid proteins that form telltale plaques in the brain. What’s troubling, though, is that the group that received a combination of vitamins E, C, and the fatty acid ALA had a greater amount of cognitive decline compared with the group given placebos or the one given coenzyme Q. “That was a really surprising finding,” said Dr. Gad Marshall, associate medical director of clinical trials at Brigham and Women’s Hospital’s Center for Alzheimer Research & Treatment, who wasn’t involved in the study. “I would have expected these supplements to have had a neutral effect on symptoms.” © 2012 NY Times Co.
Keyword: Alzheimers
Link ID: 16555 - Posted: 03.22.2012
By Lenny Bernstein, Kris Brott was more amazed than alarmed when her tongue suddenly seemed to turn upside down in her mouth. She was in the office at Quince Orchard High School in Gaithersburg, dropping off a check for her son’s baseball team, when she suddenly found herself quite literally tongue-tied. Her puzzlement gave way to panic when she reached her car and looked in the mirror. The left side of her face had collapsed. By the time she reached home, her left arm had gone numb. Soon she was dragging her left leg. It was March 15, 2010, the day before her 45th birthday. This couldn’t be happening, she thought. She was too young and much too fit. “I still kept thinking, ‘I’m not having a stroke,’ ” she recalled. She was wrong. At the hospital, emergency room physicians cleared the clot from her brain, but the damage had been done. When Brott was left with little strength on her left side despite physical therapy, she faced a long, difficult future in a body compromised by a disease of the elderly — until she decided to take control of her own recovery by returning to the gym. Researchers are learning that exercise can help younger stroke victims such as Brott regain function, even years after they are stricken. A widely cited 2011 study provides support for therapeutic approaches like the one Brott stumbled upon when she returned to the gym. © 1996-2012 The Washington Post
Keyword: Stroke
Link ID: 16554 - Posted: 03.22.2012
Christof Koch & R. Clay Reid Neuroscience is a splintered field. Some 10,000 laboratories worldwide are pursuing distinct questions about the brain across a panoply of spatio-temporal scales and in a dizzying variety of animal species, behaviours and developmental time-points. At any large neuroscience meeting, one is struck by the pace of discovery, with 50,000 or more practitioners heading away from each other in all directions, in a sort of scientific Big Bang. Although this independence is necessary, it has prevented neuroscience from entering a more mature phase, which would involve developing common standards and collaborative projects. Neurophysiologists are more likely to use each other's toothbrushes than each other's data and software; physiological results are hoarded and rarely made accessible online; molecular compounds and transgenic animals are shared only after publication. All of this has made comparisons across laboratories difficult and has slowed progress. At the Allen Institute for Brain Science in Seattle, Washington, we and our colleagues are initiating an experiment in the sociology of neuroscience — a huge endeavour that will involve several hundred scientists, engineers and technicians at the institute. Philanthropist Paul G. Allen, who founded the institute in 2003, has pledged US$300 million for the first four years of an ambitious ten-year plan that will accelerate progress in neuroscience, bringing his total commitment so far to $500 million. Our goal is to attract the best young scientists and build a series of 'brain observatories', with the aim of identifying, recording and intervening in the mouse cerebral cortex, the outermost layer of the brain. Unlike the telescopes that peer at remote events in space and time, our instruments will track the flow of information in complex, interbraided neural circuits within a layer of tissue one millimetre thick. © 2012 Nature Publishing Group,
Keyword: Brain imaging
Link ID: 16553 - Posted: 03.22.2012
by Carl Zimmer If I didn’t know Sebastian Seung was a neuroscientist, I would have pegged him as a computer game designer. His onyx-black hair seems frozen in a windstorm. He wears black sneakers, jeans, and a frayed bomber jacket over an untucked shirt covered in fluorescent blobs. If someone had blindfolded me on Vassar Street in Cambridge, Massachusetts, led me into Building 46 on the campus of MIT, past the sign that says Department of Brain and Cognitive Science, taken me up in the elevator to the fifth floor and whisked off the blindfold in Seung’s lab, I still wouldn’t have guessed he had anything to do with brains. There are no specimens floating in jars on the shelves. There are no electrodes plugged into the heads of sea slugs. Instead, I see a dozen young men gazing at monitors, some pushing their computer mice, others drawing tethered pens across digital tablets to manipulate 3-D images, each packed with more megabytes than a feature film on a Blu-ray Disc. And there is Seung himself, gazing over the shoulder of postdoc Daniel Berger, whose monitor looks like a science fiction forest, with branches and trunks colored turquoise and cherry, floating unrooted in space. I almost find myself wondering when Seung’s next game will hit the stores. But appearances to the contrary, Seung is an expert on the web of neurons that make up the brain. And the images he’s creating are part of an ambitious attempt to understand how the connections between those brain cells give rise to the mind. “How do you put together dumb cells and get something smart?” he asks. © 2012, Kalmbach Publishing Co.
Keyword: Brain imaging
Link ID: 16552 - Posted: 03.22.2012
Jon Bardin A building that once housed a Second World War torpedo factory seems an unlikely location for a project aiming to map the human brain. But the Martinos Center for Biomedical Imaging — an outpost of the Massachusetts General Hospital in an industrialized stretch of Boston's riverfront — is home to an impressive collection of magnetic resonance imaging machines. In January, I slid into the newest of these, head first. The operator ran a few test sequences to see whether I experienced any side effects from the unusually rapid changes in this machine's magnetic field. And, when I didn't — no involuntary muscle twitches or illusory flashes of light in my peripheral vision — we began. The machine hummed, then started to vibrate. For 90 minutes, I held still as it scanned my brain. That scan would be one of the first carried out by the Human Connectome Project (HCP), a five-year, US$40-million initiative funded by the National Institutes of Health (NIH) in Bethesda, Maryland, to map the brain's long-distance communications network. The network, dubbed the 'connectome', is a web of nerve-fibre bundles that criss-cross the brain in their thousands and form the bulk of the brain's white matter. It relays signals between specialized regions devoted to functions such as sight, hearing, motion and memory, and ties them together into a system that perceives, decides and acts as a unified whole. The connectome is bewilderingly complex and poorly understood. The HCP proposes to resolve this by using new-generation magnetic resonance imaging (MRI) machines, like that used to scan my brain, to trace the connectomes of more than 1,000 individuals. The hope is that this survey will establish a baseline for what is normal, shed light on what the variations might mean for qualities such as intelligence or sociability, and possibly reveal what happens if the network goes awry. © 2012 Nature Publishing Group
Keyword: Brain imaging
Link ID: 16551 - Posted: 03.22.2012
By Gareth Cook MIT scientist Sebastian Seung describes the audacious plan to find the connectome--a map of every single neuron in the brain. Here, he says, is the secret of human identity. What makes us who we are? Where is our personal history recorded, or our hopes? What explains autism or schiziphrenia or remarkable genius? Sebastian Seung argues that it’s all in the connections our neurons make. In his new book, Connectome , he argues that technology has now reached a point where it is conceivable to start mapping at least portions of the connectome. It’s a daunting task, he says, but without it, neuroscience will be stuck. He answered questions from Mind Matters editor Gareth Cook. Cook: You argue in your book that neuroscience has a fundamental problem. What is the problem? Seung: Most people are familiar with the regional approach to neuroscience: divide the brain into regions such as the "left brain" and "frontal lobe," and figure out what each region does. This approach has helped physicians interpret the symptoms of brain injuries, but at the same time has frustrating limitations. How do regions carry out their functions? Why do they malfunction in mental disorders? What happens to regions when we learn? We can never obtain satisfying answers to these questions if we consider regions as the elementary, indivisible units of the brain. An obvious solution is to understand a region by subdividing it into neurons, and figure out how the neurons work together to perform the region's function. This neuronal approach has the potential to answer the big questions above, but so far has not succeeded. In fact, those who study regions sometimes criticize those who study neurons as too focused on minutiae. © 2012 Scientific American
Keyword: Development of the Brain; Brain imaging
Link ID: 16550 - Posted: 03.22.2012
By Maia Szalavitz One of the hardest challenges for families facing autism is the problem of touch. Often, autistic children resist hugging and other types of physical contact, causing distress all around. Now, a new study offers insight into why some people shrug off physical touches and how families affected by autism may learn to share hugs without overwhelming an autistic child’s senses. Yale neuroscientists recruited 19 young adults and imaged their brain activity as a researcher lightly brushed them on the forearm with a soft watercolor paintbrush. In some cases, the brushing was quick, and in others slow: prior studies have shown that most people like slow brushing and perceive it as affectionate contact, while the faster version is felt as less pleasant and more tickle-like. None of the participants in the current study had autism, but the researchers evaluated them for autistic traits — things like a preference for sameness, order and systems, rather than social interaction. They found that participants with the highest levels of autistic traits had a lower response in key social brain regions — the superior temporal sulcus (STS) and orbitofrontal cortex (OFC) — to the slow brushing. According to Martha Kaiser, senior author of the study and associate director of the Child Neuroscience Laboratory at the Yale Child Study Center, the STS is a critical hub of the social brain. “This region is important for perceiving the people around us, for visual social stimuli and for perceiving social versus nonsocial sounds,” she says. © 2012 Time Inc.
Keyword: Autism; Pain & Touch
Link ID: 16549 - Posted: 03.22.2012
What makes people creative? What gives some of us the ability to create work that captivates the eyes, minds and hearts of others? Jonah Lehrer, a writer specializing in neuroscience, addresses that question in his new book, Imagine: How Creativity Works. Lehrer defines creativity broadly, considering everything from the invention of masking tape to breakthroughs in mathematics; from memorable ad campaigns to Shakespearean tragedies. He finds that the conditions that favor creativity — our brains, our times, our buildings, our cities — are equally broad. Lehrer joins NPR's Robert Siegel to talk about the creative process — where great ideas come from, how to foster them, and what to do when you inevitably get stuck. On comparing Shakespeare with the inventor of masking tape "I think we absolutely can lump them all together. I think one of the mistakes we've made in talking about creativity is we've assumed it's a single verb — that when people are creative they're just doing one particular kind of thinking. But looking at creativity from the perspective of the brain, we can see that creativity is actually a bundle of distinct mental processes. "... Whether you're writing a Shakespearean tragedy, or trying to come up with a new graphic design or writing a piece of software, how we think about the problem should depend on the problem itself. Creativity is really a catch-all term for a variety of very different kinds of thinking." Copyright 2012 NPR
Keyword: Attention
Link ID: 16548 - Posted: 03.20.2012
By Emily Sohn In his spare time, an otherwise ordinary 16-year old boy from New York taught himself Hebrew, Arabic, Russian, Swahili, and a dozen other languages, the New York Times reported last week. And even though it's not entirely clear how close to fluent Timothy Doner is in any of his studied languages, the high school sophomore -- along with other polyglots like him -- are certainly different from most Americans, who speak one or maybe two languages. That raises the question: Is there something unique about certain brains, which allows some people to speak and understand so many more languages than the rest of us? The answer, experts say, seems to be yes, no and it's complicated. For some people, genes may prime the brain to be good at language learning, according to some new research. And studies are just starting to pinpoint a few brain regions that are extra-large or extra-efficient in people who excel at languages. For others, though, it's more a matter of being determined and motivated enough to put in the hours and hard work necessary to learn new ways of communicating. "Kids do well in what they like," said Michael Paradis, a neurolinguist at McGill University in Montreal, who compared language learning to piano, sports or anything else that requires discipline. "Kids who love math do well in math. He loves languages and is doing well in languages." © 2012 Discovery Communications, LLC.
Keyword: Language; Development of the Brain
Link ID: 16547 - Posted: 03.20.2012
by Elizabeth Norton Since the 1930s, doctors have been jolting the brains of depressed patients with electricity to relieve their symptoms. The treatment, known as electroconvulsive therapy (ECT), works, but it can cause memory loss and confusion and lead to difficulty forming new memories. Today, physicians generally limit it to patients who are severely ill, including those at risk for suicide. Now, a brain-imaging study highlights the part of the brain most affected, perhaps pointing to safer, less-invasive ways to achieve the same results. Depression may be caused by an overactive brain, says physicist and neuroscientist Christian Schwarzbauer of the University of Aberdeen in the United Kingdom. "There may be so much internal communication that the brain becomes preoccupied with itself, less able to process information coming in from the outside world," he says, noting that studies have found that people with depression have heightened connectivity among brain networks involved in paying attention, monitoring internal and external cues, remembering the past, and controlling emotions. In a 2010 study, psychiatrist Yvette Sheline and colleagues at Washington University School of Medicine in St. Louis, Missouri, found that these overactive networks converged on a common point in a region called the dorsal medial prefrontal cortex. This common point, dubbed the dorsal nexus, may "hot wire" the brain networks together in a way that leads to depression, the authors hypothesized. © 2010 American Association for the Advancement of Science.
Keyword: Depression
Link ID: 16546 - Posted: 03.20.2012
Sharon Weinberger Why a U.S. Army soldier suspected of killing 16 civilians in Afghanistan did what he did is still unclear, but one thing is certain: his lawyers are likely to invoke emerging science about the effects of war on the brain to aid in his defense. In fact, even before Staff Sgt. Robert Bales' identity was revealed, unnamed US officials were telling major news outlets that the suspect had suffered a traumatic brain injury, or TBI. Shortly thereafter, Bales’ lawyer publicly suggested that his client suffered from Post-Traumatic Stress Disorder (PTSD), even though it does not appear to have been previously diagnosed. According to Dr. James Giordano, director of the Center for Neurotechnology Studies at the Potomac Institute for Policy Studies in Arlington, Virginia, TBI manifests itself through a variety of complaints, which may range from mild to moderate. These could include disorientation, ringing in the ears, vertigo, and headaches, as well as a more profound constellation of severe neurological and psychological symptoms, such as impaired impulse control, acting out and aggressive behavior. “What we're seeing is that TBI presents as spectrum disorder with a variety of effects,” says Giordano. In fact, some people make a complete recovery from TBI, while others develop more severe conditions down the road, and it’s difficult to predict which injuries will persist, according to Giordano. “One would think the milder the injury, the less severe the symptoms,” says Giordano. “That’s not always the case.” © 2012 Nature Publishing Group,
Keyword: Brain Injury/Concussion; Aggression
Link ID: 16545 - Posted: 03.20.2012
By C. CLAIBORNE RAY Q. Are taste buds really divided into sections on the tongue that sense four different flavors? A. Trying to navigate the sense of taste with a map of the tongue labeled with regions sensitive to four kinds of flavor would be like trying to drive cross-country with a map that did not show the Interstate System. “Although there are subtle regional differences in sensitivity to different compounds over the lingual surface, the oft-quoted concept of a ‘tongue map’ defining distinct zones for sweet, bitter, salty and sour has largely been discredited,” according to a review article in The Journal of Cell Biology in August 2010. That map of relative sensitivities, frequently reproduced in textbooks after the researcher Edwin G. Boring sketched it in 1942, neglected the “fifth taste,” called umami, from the Japanese for rich, meaty protein flavors. The outdated map also did not reflect later findings that taste buds, clusters of sensitive cells, have different degrees of sensitivity to molecules carrying more than one basic taste and that these clusters are distributed across the entire surface of the tongue. Recognizing bitterness is thought to protect against bitter poisons; sweet tastes signal sugars and carbohydrates; salty tastes signal sodium compounds and other salts; and sour tastes indicate organic acids. The tongue may also have specialized receptors for fatty flavors, researchers say. © 2012 The New York Times Company
Keyword: Chemical Senses (Smell & Taste)
Link ID: 16544 - Posted: 03.20.2012
Brendan Borrell Paulo Mazzafera punched a pea-sized disc out of a waxy green coffee leaf, then placed the disc in a small vial with a mixture of chloroform and methanol to dissolve it. Later, he loaded the extract, along with 95 other samples, into a high-performance liquid chromatography machine, which separates out each chemical component. When the plant physiologist returned to his lab at the University of Campinas in Brazil the next morning, he sat down at his laptop to examine the results. Scrolling from one chromatogram to the next, he scrutinized the peak representing caffeine. In one plant, it was missing. Mazzafera ran the sample twice more and then, just before noon, called his collaborator Bernadete Silvarolla, based at the agricultural station nearby, to share the news. “Are you sure?” she asked. He was. In fact, he was thrilled. After screening thousands of plants over the course of two decades, his project to find a naturally caffeine-free coffee finally seemed to be bearing fruit. That was in late 2003. Coffee contains some 2,000 chemical compounds that give the drink its enticing aroma and flavour, including caffeine, a stimulant and natural pesticide. Removing the caffeine while leaving all the others intact poses a significant challenge. Brewers have generally turned to chemistry: Ludwig Roselius of Bremen, Germany, patented the first commercial decaffeination process in 1905. But his coffee, marketed as Kaffee HAG, used benzene in the extraction process, and the chemical was later replaced by less toxic solvents. Today, companies may instead douse raw green coffee beans in high-pressure liquid carbon dioxide or soak them in hot water for several hours to remove the caffeine before roasting. Aficionados say that all these methods destroy the taste, but the decaf market is still worth US$2 billion a year. © 2012 Nature Publishing Group
Keyword: Drug Abuse
Link ID: 16543 - Posted: 03.20.2012


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