by Jessica Hamzelou ALZHEIMER'S disease is more prevalent in older people, but we have never known why. Now it seems that about 80 per cent of our brain cells are vulnerable to a process that can turn them toxic. For the first time, cells in the brains of people with Alzheimer's have been shown to "senesce" - a mechanism that stops them dividing and starts them on a path of destruction. With hundreds of experimental treatments for the disease falling by the wayside, we need a new target and it seems as if we have now found one. The discovery of huge numbers of senescent cells in people with Alzheimer's suggests that they play a key role in the condition. Cells that continually replicate in the body, such as those in the skin, lung and kidney, eventually accumulate DNA damage - typically with age. Not all of these damaged cells die though, instead some senesce. When this happens, biological changes within the cell prevent it from dividing or carrying out its normal functions. Research suggests that senescing cells also start producing proteins that trigger inflammation. "It's pretty clear that cell senescence evolved to protect us against cancer," says Judith Campisi of the Buck Institute for Research on Aging in Novato, California. The idea is that once cells accumulate DNA damage, they senesce to avoid incorrect division that can lead to cancer. The benefit of this mechanism over self-destruction is that it sends out a call to the immune system to destroy nearby cells that might also be affected. © Copyright Reed Business Information Ltd.

Keyword: Alzheimers
Link ID: 17306 - Posted: 09.27.2012

By Sandra G. Boodman, The 80th birthday party for Josephine van Es marked two milestones, only one of which was apparent at the time. Held in November 2004 at her daughter’s house in Rehoboth Beach, Del., the event was a celebration of her longevity, good health and loving family. It also marked one of the last times van Es can remember feeling well and not beset by the pain that developed soon afterward and has left the inside of her mouth feeling perpetually scalded and with a constant metallic taste. “It’s awful,” said van Es, 87, who says the burning is worse than the taste, which she likens to “sucking on a penny.” Her daughter Karen van Es says that her mother’s problem has taken a toll on both their lives. For nearly eight years, she has taken time from her job at a Northern Virginia veterinary clinic to ferry her mother, who lives independently in a condominium in Lewes, Del., to doctors in Delaware, Philadelphia and Washington. She also has contacted specialists in Florida and Canada hoping one would propose an effective remedy for an ailment that took more than a year to diagnose and has so far eluded treatment. “She tells me, ‘I just feel rotten all the time,’ ” said Karen van Es, 63, an only child who speaks to her mother every day and sees her often. “My mother has lost confidence as a result of this,” Karen van Es said, adding that she often feels helpless and frustrated about not being able to do more. © 1996-2012 The Washington Post

Keyword: Chemical Senses (Smell & Taste); Pain & Touch
Link ID: 17305 - Posted: 09.26.2012

By GRETCHEN REYNOLDS Can you improve your body’s ability to remember by making it move? That rather odd-seeming question stimulated researchers at the University of Copenhagen to undertake a reverberant new examination of just how the body creates specific muscle memories and what role, if any, exercise plays in the process. To do so, they first asked a group of young, healthy right-handed men to master a complicated tracking skill on a computer. Sitting before the screen with their right arm on an armrest and a controller similar to a joystick in their right hand, the men watched a red line squiggle across the screen and had to use the controller to trace the same line with a white cursor. Their aim was to remain as close to the red squiggle as possible, a task that required input from both the muscles and the mind. The men repeated the task multiple times, until the motion necessary to track the red line became ingrained, almost automatic. They were creating a short-term muscle memory. The term “muscle memory” is, of course, something of a misnomer. Muscles don’t make or store memories. They respond to signals from the brain, where the actual memories of any particular movement are formed and filed away. But muscle memory — or “motor memory,” as it is more correctly referred to among scientists — exists and can be quite potent. Learn to ride a bicycle as a youngster, abandon the pastime and, 20 years later, you’ll be able to hop on a bicycle and pedal off. Copyright 2012 The New York Times Company

Keyword: Learning & Memory
Link ID: 17304 - Posted: 09.26.2012

By Gary Stix Market researcher SharpBrains has predicted that the brain fitness industry will range anywhere from $2 billion to $8 billion in revenues by 2015. That’s a wide swath, but the companies that sell brain-tuning software could conceivably hit at least the low end of their sales target by then. The question that persists is whether any of these games and exercises actually enhance the way your brain works, whether it be memory, problem solving or the speed with which you execute a mental task. True, study participants often get better at doing an exercise that is supposedly related to a given facet of cognition. But the ability to master a game or ace a psych test often doesn’t translate into better cognition when specific measures of intelligence are assayed later. One area of research that has shown some promise relates to a method of boosting the mental scratchpad of working memory— keeping in your head a telephone number long enough to dial, for instance. Some studies have demonstrated that a particular technique to energize working memory betters the reasoning and problem-solving abilities known as fluid intelligence. Yet two new studies have now called into question the earlier research on working memory. A recent online publication in the Journal of Experimental Psychology led by a group at the Georgia Institute of Technology showed that 20 sessions on a working memory task did not did not result in a later acing of tests of cognitive ability. Similarly, a group at Case Western Reserve University tried the same “dual n-back test” and published a report in the journal Intellgence that found that better scores did not produce higher tallies for working memory and fluid intelligence. An n-back test requires keeping track of a number, letter or image “n” places back. A dual n-back demands the simultaneous remembering of both a visual and auditory cue perceived a certain number of places back. © 2012 Scientific American

Keyword: Learning & Memory
Link ID: 17303 - Posted: 09.26.2012

The brain that revolutionized physics now can be downloaded as an app for $9.99. But it won't help you win at Angry Birds. While Albert Einstein's genius isn't included, an exclusive iPad application launched Tuesday promises to make detailed images of his brain more accessible to scientists than ever before. Teachers, students and anyone who's curious also can get a look. A medical museum under development in Chicago obtained funding to scan and digitize nearly 350 fragile and priceless slides made from slices of Einstein's brain after his death in 1955. The application will allow researchers and novices to peer into the eccentric Nobel winner's brain as if they were looking through a microscope. "I can't wait to find out what they'll discover," said Steve Landers, a consultant for the National Museum of Health and Medicine Chicago who designed the app. "I'd like to think Einstein would have been excited." After Einstein died, a pathologist named Thomas Harvey performed an autopsy, removing the great man's brain in hopes that future researchers could discover the secrets behind his genius. Harvey gave samples to researchers and collaborated on a 1999 study published in the Lancet. That study showed a region of Einstein's brain - the parietal lobe - was 15 percent wider than normal. The parietal lobe is important to the understanding of math, language and spatial relationships. © 2012 Hearst Communications Inc

Keyword: Miscellaneous
Link ID: 17302 - Posted: 09.26.2012

By Sarah Estes and Jesse Graham It might be time to pencil in "awe cultivation" on your to-do list. Although religious thinkers like Søren Kierkegaard cast awe as a state of existential fear and trembling, new research by psychologists at Stanford and the University of Minnesota shows that experiencing awe can actually increase well-being, by giving people the sense that they have more time available. That sounds much more enjoyable than trying to power through one more hour on Redbull and fumes. Just what is this elusive emotion, and how can one nurture it in our time-pressed world? Although awe has played a significant role in the histories of religion, art, and other transcendental pursuits, it has received scant attention from emotion researchers. Noting the paucity of data, social psychologists Dacher Keltner and Jonathan Haidt developed a working prototype in a 2003 paper, delineating awe's standing in the research taxonomy. After reviewing accounts of psychological, sociological, religious, artistic, and even primordial awe (awe toward power), the researchers surmised that awe universally involved the perception of vastness and the need to accommodate the experience into one's present worldview. That is, awe is triggered by some experience so expansive (in either a positive or negative way) that one’s mental schemas have to be adjusted in order to process it. Nearly ten years later, awe research is beginning to come into its own. The self-help market has continued to grow quickly, and research on positive emotions has kept apace. Even corporations and politicians have taken note of some of the ways that emotion research links into everything from productivity to voting and buying behavior. So it should come as no surprise that psychologists are now experimenting in domains formerly left to clergy, clinicians, and artists. © 2012 Scientific American,

Keyword: Attention
Link ID: 17301 - Posted: 09.26.2012

By PAULINE W. CHEN, M.D. Recounting her father’s struggle with cancer was difficult for the young woman, even several years after his death. He’d endured first surgery and then chemotherapy and radiation, she told me, and the cancer had gone into remission. He was thrilled, but the aggressive treatment left him with chronic, debilitating pain. Once active, he struggled to get around in his own home. “It wasn’t the cancer that got him,” the daughter said. “It was the pain.” Her father had turned to all of his doctors, with little relief. His surgeon had looked at his operative wounds, pronounced them well healed, then stated that they were in no way responsible for his disability. Both his cancer doctor and his radiation doctor congratulated him on being in remission but then declined to prescribe pain medications since they were no longer treating him and couldn’t provide ongoing follow-up and dosing guidance. His primary care doctor listened intently to his descriptions of his limitations, but then prescribed only small amounts of pain meds that offered fleeting relief at best. “I’ll never forget what my father had to go through,” she said, weeping. “I wouldn’t wish this on anyone.” I wish I could have reassured her that her father’s case was unusual. Sadly, according to a new study in The Journal of Clinical Oncology, a significant percentage of cancer patients continue to suffer from pain as her father did. Copyright 2012 The New York Times Company

Keyword: Pain & Touch; Drug Abuse
Link ID: 17300 - Posted: 09.26.2012

Analysis by Tracy Staedter From the department of "I hope this never happens to me," scientists have used a laser to manipulate the behavior of a worm. First, a research team from the Howard Hughes Medical Institute genetically engineered a tiny, transparent worm called Caenorhabditis elegans to have neurons that give off fluorescent light. This allowed the neurons to be tracked during experiments. The scientists also engineered the neurons to be sensitive to light, which made it possible to activate them with pulses of laser light. Next, they built a movable table for the worm to crawl on, keeping it aligned beneath a camera and laser. They used the laser to activate a single neuron at a time. By doing so, they were able to control a worm's behavior and its senses. In tests, which the researchers published in the journal Nature, the laser made the worm turn left or right and move through a loop. The laser also tricked the worm brain into thinking food was nearby. The worm, in turn, wiggled toward what it thought was a meal. The research, which on the surface seems like a bit of a circus, actually is important because it shows scientists which neurons are responsible for what. "If we can understand simple nervous systems to the point of completely controlling them, then it may be a possibility that we can gain a comprehensive understanding of more complex systems," said Sharad Ramanathan, an Assistant Professor of Molecular and Cellular Biology, and of Applied Physics. "This gives us a framework to think about neural circuits, how to manipulate them, which circuit to manipulate and what activity patterns to produce in them." © 2012 Discovery Communications, LLC

Keyword: Development of the Brain
Link ID: 17299 - Posted: 09.26.2012

by Gisela Telis In the industrialized world, women live at least 5 years longer, on average, than men. Scientists have attributed that difference to everything from healthier habits to hardier cells. Now, a new study that analyzes the longevity of eunuchs, or castrated men, suggests that testosterone may play a part in shortening men's lives. The idea that testosterone, the male sex hormone, affects lifespan isn't new. Neutered dogs and other animals that have had their sources of testosterone removed often live longer than their intact counterparts. But studies on the connection between castration and longevity in humans are harder to come by, and the results have been inconclusive. A 1969 study of institutionalized patients in Kansas found that castrated men lived an average of 14 years longer than other men in the same facility, but a 1993 study of Italian castrati (singers castrated as boys to preserve their high voices) found nothing unusual about their longevity. Almost 5 years ago, biologist Kyung-Jin Min of Inha University in Incheon, Korea, found himself considering this lack of data while watching a Korean TV drama about eunuchs. Min began to wonder if Korea's rich historical records could shed light on the link between castration and longevity in humans. Until the late 19th century, Korean rulers employed eunuchs to serve the royal court. These eunuchs were allowed to marry and adopt castrated boys as their sons. The Yang-Se-Gye-Bo, a genealogical record of the eunuch families, has survived, and it documents the birth and death dates and other personal details of 385 eunuchs who lived between the mid-16th century and the mid-19th century. © 2010 American Association for the Advancement of Science.

Keyword: Hormones & Behavior; Sexual Behavior
Link ID: 17298 - Posted: 09.25.2012

By RICHARD A. FRIEDMAN, M.D. You will never guess what the fifth and sixth best-selling prescription drugs are in the United States, so I’ll just tell you: Abilify and Seroquel, two powerful antipsychotics. In 2011 alone, they and other antipsychotic drugs were prescribed to 3.1 million Americans at a cost of $18.2 billion, a 13 percent increase over the previous year, according to the market research firm IMS Health. Those drugs are used to treat such serious psychiatric disorders as schizophrenia, bipolar disorder and severe major depression. But the rates of these disorders have been stable in the adult population for years. So how did these and other antipsychotics get to be so popular? Antipsychotic drugs have been around for a long time, but until recently they were not widely used. Thorazine, the first real antipsychotic, was synthesized in the 1950s; not just sedating, it also targeted the core symptoms of schizophrenia, like hallucinations and delusions. Later, it was discovered that antipsychotic drugs also had powerful mood-stabilizing effects, so they were used to treat bipolar disorder, too. Then, starting in 1993, came the so-called atypical antipsychotic drugs like Risperdal, Zyprexa, Seroquel, Geodon and Abilify. Today there are 10 of these drugs on the market, and they have generally fewer neurological side effects than the first-generation drugs. Originally experts believed the new drugs were more effective than the older antipsychotics against such symptoms of schizophrenia as apathy, social withdrawal and cognitive deficits. But several recent large randomized studies, like the landmark Catie trial, failed to show that the new antipsychotics were any more effective or better tolerated than the older drugs. © 2012 The New York Times Company

Keyword: Schizophrenia
Link ID: 17297 - Posted: 09.25.2012

By Tori Rodriguez Feeling sociable or reckless? You might have toxoplasmosis, an infection caused by the microscopic parasite Toxoplasma gondii, which the CDC estimates has infected about 22.5 percent of Americans older than 12 years old. Researchers tested participants for T. gondii infection and had them complete a personality questionnaire. They found that both men and women infected with T. gondii were more extroverted and less conscientious than the infection-free participants. These changes are thought to result from the parasite's influence on brain chemicals, the scientists write in the May/June issue of the European Journal of Personality. “Toxoplasma manipulates the behavior of its animal host by increasing the concentration of dopamine and by changing levels of certain hormones,” says study author Jaroslav Flegr of Charles University in Prague, Czech Republic. Although humans can carry the parasite, its life cycle must play out in cats and rodents. Infected mice and rats lose their fear of cats, increasing the chance they will be eaten, so that the parasite can then reproduce in a cat's body and spread through its feces. In humans, T. gondii's effects are more subtle; the infected population has a slightly higher rate of traffic accidents, studies have shown, and people with schizophrenia have higher rates of infection—but until recent years, the parasite was not thought to affect most people's daily lives. In the new study, a pattern appeared in infected men: the longer they had been infected, the less conscientious they were. © 2012 Scientific American,

Keyword: Emotions
Link ID: 17296 - Posted: 09.25.2012

by Emily Underwood A human newborn's brain is uniquely impressionable, allowing social interactions and the environment to shape its development. But this malleability may come with a price, a new study finds. A comparison of juvenile chimpanzee and human brains suggests that differences in the development of myelin—the fatty sheath that surrounds nerve fibers—may contribute not only to our unusual adaptability, but also to our vulnerability to psychiatric diseases that start in early adulthood. Research increasingly suggests that psychiatric illnesses like depression and schizophrenia may involve problems with the timing of neural signals, says Douglas Fields, a neuroscientist at the National Institutes of Health in Bethesda, Maryland, who was not involved in the study. The nerve fibers, or axons, that connect neurons are usually protected by myelin, which enhances the neural relay of information throughout the brain. "Myelin speeds transmission of information [by] at least 50 times," Fields says, "so it matters a great deal whether or not an axon becomes myelinated." Humans start out with comparatively few myelinated axons as newborns. We experience a burst of myelin development during infancy that is followed by a long, slow growth of myelin that can last into our thirties, says Chet Sherwood, a neuroscientist at George Washington University in Washington, D.C., and a co-author of the new study. In contrast, other primates, such as macaques, start out with significantly more myelin at birth, but stop producing it by the time they reach sexual maturity. However, Sherwood says, "extraordinarily little data exists" on brain growth and the development of myelin in our closest genetic relatives, chimpanzees. © 2010 American Association for the Advancement of Science.

Keyword: Development of the Brain; Evolution
Link ID: 17295 - Posted: 09.25.2012

By Ilana Yurkiewicz It’s tough to prove gender bias. In a real-world setting, typically the most we can do is identify differences in outcome. A man is selected for hire over a woman; fewer women reach tenure track positions; there’s a gender gap in publications. Bias may be suspected in some cases, but the difficulty in using outcomes to prove it is that the differences could be due to many potential factors. We can speculate: perhaps women are less interested in the field. Perhaps women make lifestyle choices that lead them away from leadership positions. In a real-world setting, when any number of variables can contribute to an outcome, it’s essentially impossible to tease them apart and pinpoint what is causative. The only way to do that would be by a randomized controlled experiment. This means creating a situation where all variables other than the one of interest are held equal, so that differences in outcome can indeed be attributed to the one factor that differs. If it’s gender bias we are interested in, that would mean comparing reactions toward two identical human beings – identical in intelligence, competence, lifestyle, goals, etc. – with the one difference between them that one is a man and one is a woman. Not exactly a situation that exists in the real world. But in a groundbreaking study published in PNAS last week by Corinne Moss-Racusin and colleagues, that is exactly what was done. On Wednesday, Sean Carroll blogged about and brought to light the research from Yale that had scientists presented with application materials from a student applying for a lab manager position and who intended to go on to graduate school. Half the scientists were given the application with a male name attached, and half were given the exact same application with a female name attached. Results found that the “female” applicants were rated significantly lower than the “males” in competence, hireability, and whether the scientist would be willing to mentor the student. © 2012 Scientific American,

Keyword: Sexual Behavior
Link ID: 17294 - Posted: 09.25.2012

Sandrine Ceurstemont, editor, New Scientist TV Chimps may be similar to us in many ways but they can't compete when it comes to brain size. Now for the first time we can see when the differences emerge by tracking the brain development of unborn chimps. As seen in this video, Tomoko Sakai and colleagues from Kyoto University in Japan subjected a pregnant chimp to a 3D ultrasound to gather images of the fetus between 14 and 34 weeks of development. The volume of its growing brain was then compared to that of an unborn human. The team found that brain size increases in both chimps and humans until about 22 weeks, but after then only the growth of human brains continues to accelerate. This suggests that as the brain of modern humans rapidly evolved, differences between the two species emerged before birth as well as afterwards. The researchers now plan to examine how different parts of the brain develop in the womb, particularly the forebrain, which is responsible for decision-making, self-awareness and creativity. If you enjoyed this post, watch the first video MRI of unborn twins or the first MRI movie of a baby's birth. © Copyright Reed Business Information Ltd.

Keyword: Development of the Brain; Evolution
Link ID: 17293 - Posted: 09.25.2012

By DAVID K. RANDALL SOMETIME in the dark stretch of the night it happens. Perhaps it’s the chime of an incoming text message. Or your iPhone screen lights up to alert you to a new e-mail. Or you find yourself staring at the ceiling, replaying the day in your head. Next thing you know, you’re out of bed and engaged with the world, once again ignoring the often quoted fact that eight straight hours of sleep is essential. Sound familiar? You’re not alone. Thanks in part to technology and its constant pinging and chiming, roughly 41 million people in the United States — nearly a third of all working adults — get six hours or fewer of sleep a night, according to a recent report from the Centers for Disease Control and Prevention. And sleep deprivation is an affliction that crosses economic lines. About 42 percent of workers in the mining industry are sleep-deprived, while about 27 percent of financial or insurance industry workers share the same complaint. Typically, mention of our ever increasing sleeplessness is followed by calls for earlier bedtimes and a longer night’s sleep. But this directive may be part of the problem. Rather than helping us to get more rest, the tyranny of the eight-hour block reinforces a narrow conception of sleep and how we should approach it. Some of the time we spend tossing and turning may even result from misconceptions about sleep and our bodily needs: in fact neither our bodies nor our brains are built for the roughly one-third of our lives that we spend in bed. © 2012 The New York Times Company

Keyword: Sleep
Link ID: 17292 - Posted: 09.25.2012

By Susan Milius Let’s take a minute to turn faces upside down. Pick any face. Ignore beards, glasses, hairdos or lack of any hair to do, and upend the facial features of Charles Darwin, Ray Charles or anyone named Charlotte who reads Science News. People who normally remember or match a face perfectly well have trouble when it is standing on its head. But before there’s a chorus of “well, obviously,” let’s try turning dogs upside down, too. Most people who don’t breed dogs or judge shows don’t recognize an individual dog nearly as well as a person’s face to begin with. And when pictures of poodles and Irish setters flip upside down in quizzes of learning and memory, people struggle a bit more than they do with the natural versions. But scores drop only modestly with these flipped-dog pics, compared with the dramatic drop for facial flips. The disproportionate decline in remembering inverted faces has shown up in a variety of recall tests, with comparison groups from dogs to bridges, airplanes, stick figures, even clothing from 17th and 18th century paintings. Upside-down faces are where quiz scores really slump, and researchers view that slump as one of the signs that test-takers are actually experts at face perception. A dog is a dog in any orientation. Same for other organisms and objects. But right-side-up faces apparently are so compelling that people have become especially masterful at recognizing the human visage. Know-it-at-a-glance holistic techniques behind this mastery fail when the world turns upside down. access © Society for Science & the Public 2000 - 2012

Keyword: Attention; Evolution
Link ID: 17291 - Posted: 09.22.2012

by Virginia Morell Bumblebees foraging in flowers for nectar are like salesmen traveling between towns: Both seek the optimal route to minimize their travel costs. Mathematicians call this the "traveling salesman problem," in which scientists try to calculate the shortest possible route given a theoretical arrangement of cities. Bumblebees, however, take the brute-force approach: For them, it's simply a matter of experience, plus trial and error, scientists report in the current issue of PLoS Biology. The study, the first to track the movements of bumblebees in the field, also suggests that bumblebees aren't using cognitive maps—mental recreations of their environments—as some scientists have suggested, but rather are learning and remembering the distances and directions that need to be flown to find their way from nest to field to home again. A team of researchers from Queen Mary, University of London outfitted seven bumblebees with tiny radar transponders, which they stuck on the bees' backs with double-sided tape. They trained the bees to forage nectar from five blue artificial flowers (see video). Each artificial flower had a yellow landing platform and a single drop of sucrose, just enough to fill one-fifth of a bumblebee's tank capacity, to ensure that the bees would visit all five flowers on each foraging bout. The scientists placed the flowers in a field at Rothamsted Research, a biological research station north of London, in October—a time of year when there are few natural sources of nectar and pollen and the bees are more likely to focus on the artificial flowers. They arranged the flowers in a pentagon and spaced them 50 meters apart; that distance is more than three times as far as bumblebees can see, so the bees must actively fly around to locate their next target. A motion-triggered Webcam was attached to each flower to record the bees' visits. Then, every day for a month, each bee was freed to forage for 7 hours. © 2010 American Association for the Advancement of Science

Keyword: Animal Migration; Evolution
Link ID: 17290 - Posted: 09.22.2012

By Gary Stix Neuroscientists have devoted inordinate energy in recent years to publicize the need for, not only gene maps, but for a full wiring diagram of all brain circuits. The benefits of a connectome as it is known might yield new understanding that could eventually result in pharmaceuticals for intractable psychiatric disorders. This ultimate neural network might even divvy up intimations of the workings of consciousness. The futurist contingent, many of whom began careers hacking computers not neural circuity, has speculated that a whole brain blueprint of you or me might be copied to a hard drive so that we can live for a digital eternity like Max Headroom. Christof Koch, the chief scientist at the Allen Institute for Brain Science, the organization that produced the gene map, dismissed facile optimism about the prospects for these scenarios with a commentary in Science last month. In it, he calculated that it could take 2000 years to analyze all of the possible interactions among the 1,000 different proteins that populate a single synapse. Koch then went on to speculate about a way of reducing the complexity of such calculations. The question still remains of how we will know when we have actually started to make sense of the tangle of wiring that populates the deepest recesses inside our skulls. One plausible answer: when the FDA approves a new drug that fundamentally advances treatment of schizophrenia, the psychiatric illness that has aberrant effects on a multitude of neural pathways—an iconic example of the brain’s underlying complexity. © 2012 Scientific American

Keyword: Schizophrenia
Link ID: 17289 - Posted: 09.22.2012

The human brain is big and complicated. There has been a map for gene expression in mice brains available for a number of years but human brains are a thousand times bigger and a little harder to come by for post-mortem research. But published today is a high-resolution 3D atlas of the human brain created by an international team led by Michael Hawrylycz of the Allen Institute for Brain Science in Seattle. The project was launched in March 2008 with a budget of $55 million. Working with just two whole male brains and a single hemisphere from a third, the team used around 900 precise subdivisions and 60,000 gene expression probes to create the atlas. This image is a 3D rendering of just one of the genes in internal brain structures overlaid onto an MRI scan. The level of gene expression at the different points on the map is indicated on a colour scale, with blue dots reflecting relatively low expression and red dots reflecting high expression. The aim of the project is to provide a platform for further study into gene expression in the brain and how it is involved in normal and abnormal brain function. The Allen Brain Atlas is freely accessible online. Journal reference: Nature, DOI: 10.1038/nature11405 © Copyright Reed Business Information Ltd.

Keyword: Brain imaging; Genes & Behavior
Link ID: 17288 - Posted: 09.22.2012

By Janet Raloff Most people would never equate downing a well-dressed salad or a fried chicken thigh with toking a joint of marijuana. But to Joseph Hibbeln of the National Institutes of Health, the comparison isn’t a big stretch. New animal experiments by Hibbeln and his colleagues have recently shown that the body uses a major constituent in most vegetable oils to make its own versions of the psychoactive ingredient in marijuana. Called endocannabinoids, these natural compounds play a role in heightening appetite. So overproducing them unnecessarily boosts hunger, similarly to how pot triggers the munchies (SN: 6/19/10, p. 16). If what happens in people mirrors what happens in animals, then the prevalence of soybean oil, corn oil and other polyunsaturated vegetable oils in today’s Western diet means your body is “dumping out a lot of these marijuana-like molecules into your brain,” explains Hibbeln, a nutritional neuroscientist. “You’re chronically a little bit stoned.” Vegetable oil’s link to endocannabinoids is just one example of newfound and surprising ways that foods can confuse calorie-sensing networks and foster obesity — in some cases by damaging the brain. Especially troubling: Excess body weight itself can exaggerate the risk of the brain telling a well-fueled body that it is running on empty. By understanding what messes with the body’s satiety meters and why, scientists hope to identify tactics for reducing a diner’s likelihood of becoming another statistic in the obesity epidemic. © Society for Science & the Public 2000 - 2012

Keyword: Obesity; Drug Abuse
Link ID: 17287 - Posted: 09.22.2012