By Tina Hesman Saey Old memories may get the boot from new brain cells. A new rodent study shows that newborn neurons destabilize established connections among existing brain cells in the hippocampus, a part of the brain involved in learning and memory. Clearing old memories from the hippocampus makes way for new learning, researchers from Japan suggest in the Nov. 13 Cell. Other researchers had proposed the idea that neurogenesis, the birth of new neurons, could disrupt existing memories, but the Cell paper is the first to show evidence supporting the idea, says Paul Frankland, a neuroscientist at the Hospital for Sick Children in Toronto. Scientists have known that memories first form in the hippocampus and are later transferred to long-term storage in other parts of the brain. For some amount of time the memory resides both in the hippocampus and elsewhere in the brain. What’s not been known is how, after a few months or years, the memory is gradually cleared from the hippocampus. Researchers have also debated the role of neurogenesis in learning and memory. The hippocampus is one of only two places in the adult brain where scientists know that new neurons form. On the basis of previous studies, many researchers think new neurons stabilize memory circuits or are somehow otherwise necessary to form new memories. The new study suggests the opposite: Newborn neurons weaken or disrupt connections that encode old memories in the hippocampus. © Society for Science & the Public 2000 - 2009

Keyword: Learning & Memory; Neurogenesis
Link ID: 13461 - Posted: 06.24.2010

By Jesse Bering My mother used to say, “there’s somebody out there for everybody.” It sounds sweet, I know, but when you realize she would say this only in jaw-dropping astonishment at seeing a loving couple out in public in which both partners were, shall we say, aesthetically shortchanged in some eye-catching way, my dearly departed mother somehow doesn’t sound like such a Polyanna anymore. But she got it basically right. When two people are in love, the world whittles away to them alone, and as new research findings suggest, a mere reminder of that other person can make everything seem a little more manageable—even, as it turns out, physical pain. In a study published this month in Psychological Science, psychology graduate student Sarah Master of the University of California, Los Angeles, and fellow researchers invited 25 couples into their laboratory for a study on pain perception. The females—in this study, anyway—got to be the recipients of the experimentally induced pain stimuli. While the male partner was away in another room having his photographs taken for later use in the study, the woman was instructed to place her arm through an opaque curtain. An experimenter on the other side of the curtain first assessed each woman’s “pain threshold” for thermal stimulation, which produces a sharp, acute, prickling pain sensation within about a tenth of a second. Once the investigators determined each woman’s subjective pain threshold for moderate discomfort—operationalized as a score of “10” on a pain-rating scale of 0 to 20—they proceeded to the experiment, in which the women were subjected to 84 further pain trials. Ouch! Unbeknownst to the female participants, half of these thermal stimulations were administered at the women’s individually predetermined pain threshold levels, and half were set at 1° C above these moderate discomfort levels. © 1996-2009 Scientific American Inc

Keyword: Emotions; Pain & Touch
Link ID: 13460 - Posted: 06.24.2010

Linda Geddes, reporter A gene therapy that appears to bulk up muscle mass and strength in monkeys - reported today in Science Translational Medicine - will undoubtedly raise fresh concerns about the potential for gene doping in sport. We already know that some athletes use drugs like erythropoietin to increase the amount of oxygen their blood delivers, and steroids to bulk up muscle mass. The big advantage with gene doping is that it should be harder to detect. That's because it's difficult to test for a protein that the body already produces, especially when its levels naturally vary between individuals - which might explain why some people are inherently better at sports than others. In the new study, Janaiah Kota and colleagues at Nationwide Children's Hospital in Columbus, Ohio, used gene therapy to add extra copies of the follistatin gene into the leg muscles of monkeys. Follistatin has been previously shown in mice to block myostatin, a protein that decreases muscle mass, resulting in bulked up "mighty mice". Monkeys injected with the gene also seemed to bulk up, and when Kota's team analyzed their leg muscles with a device that measures force, they found that the muscles injected with the follistatin gene were also stronger than normal muscles. They hope the approach could eventually be used to treat the severe muscle weakness associated with neuromuscular disorders like muscular dystrophy and multiple sclerosis. © Copyright Reed Business Information Ltd.

Keyword: Muscles; Genes & Behavior
Link ID: 13459 - Posted: 06.24.2010

by Aria Pearson If you struggle to follow the conversation at noisy parties, music lessons might help. Nina Kraus and colleagues at Northwestern University in Evanston, Illinois, have previously shown that playing an instrument seems to enhance our ability to pick up emotional cues in conversationSpeaker. Now her team has found differences in brain activity that they say make musicians better at picking out speech from background noise. After establishing that musicians are better at repeating a sentence heard in the presence of background noise, the researchers asked 16 lifelong musicians and 15 non-musicians to listen to speech in a quiet or noisy environment while they were wearing scalp electrodes to monitor their brain activity. Slow reactions Background noise delayed the brain's response, but this delay was much shorter in the musicians. What's more, in the noisy environment, the musicians' brainwaves were more similar to the sound waves of the speech than in non-musicians. The difference could be partly genetic, but Kraus says training is likely to help. "Musicians spend a lot of time extracting particular sounds from a soundscape." © Copyright Reed Business Information Ltd.

Keyword: Hearing; Attention
Link ID: 13458 - Posted: 06.24.2010

by Anil Ananthaswamy A telltale signature of consciousness has been detected that takes us a step closer to disentangling the brain activity underlying conscious and unconscious brain processes. It turns out that there is a similar pattern of neural activity each time we become conscious of the same picture, but not if we process information from the image unconsciously. These contrasting patterns of activity can now be detected via brain scans, and could one day help determine if patients with brain damage are conscious. They might even be used to probe consciousness in animals. "It's very exciting work," says neuroscientist Raphaël Gaillard of the University of Cambridge, who was not involved in the work. "The use of a reproducibility measure to disentangle conscious and non-conscious processes is genuinely new." Gaillard has previously shown that coordinated activity across the entire brain is one of the signatures of consciousness . Consistent signals So far, efforts to find a brain signature of consciousness have focused on the intensity of neural activity, how long it lasts, and whether signals tend to be synchronised across different regions of the brain. "We were looking for something other than the intensity and duration of the neural activity that characterises conscious neural processing," says Aaron Schurger of Princeton University in New Jersey, who led the new work. © Copyright Reed Business Information Ltd.

Keyword: Attention; Brain imaging
Link ID: 13457 - Posted: 06.24.2010

By Tina Hesman Saey Silver-tongued humans may owe their language prowess to a foxy friend. A new study provides more evidence that the human version of a protein known as FOXP2 may have aided the evolution of language. Chimpanzees and many other animals have FOXP2, but the human version differs at two links in the chain of amino acids that make up the protein. Scientists have suspected that those two amino acid changes were not merely cosmetic, but might alter the way FOXP2 functions, perhaps paving the way for the evolution of language. The new study finds that human FOXP2, compared with the chimp version, alters the activity of at least 116 genes in brain cells grown in laboratory dishes, neurogeneticist Daniel Geschwind of the University of California, Los Angeles and colleagues report in the Nov. 12 Nature. Of the affected genes, 61 showed higher activity with human FOXP2 than the chimp form. Many of those genes are involved in neural development and the production of collagen, cartilage and soft tissues. Those results suggest that the protein may play roles in shaping both the brain and the vocal apparatus that makes speech possible. The human version of the protein decreased activity of 55 genes. Together these findings are “consistent with these genes being part of a molecular circuit related to human cognition,” including circuits needed for language, Geschwind says. He thinks FOXP2 and the genes it regulates make the brain better able to integrate sensory information with movements, as in hearing sounds and then shaping the tongue, lips and vocal tract to reproduce those sounds. © Society for Science & the Public 2000 - 2009

Keyword: Language; Genes & Behavior
Link ID: 13456 - Posted: 06.24.2010

By Lori Cuthbert I've been under some stress lately. Not the minor kind that everyday life usually brings, like ferrying kids to and fro, working, or the usual frustrations of owning a house. I'm talking about the big stresses that can clobber us, whether good or bad. In my case, good, but still, immensely stressful. Over the past week, the stress has intensified. And so has my desire to consume sweet things. Candy (handy that Halloween just happened). Cake (even with candy on top). More candy. My reaction has been, What the...? I don't eat sweets. I don't even have a sweet tooth; I have a potato chip tooth. Don't care for chocolate, particularly, but there I am, nightly, squeezing chocolate syrup on top of my orange-iced ginger cake with ice cream and whipped cream. First, this has me alarmed and has to stop for obvious reasons involving my figure. But second, it's got me wondering whether there's a link between stress and cravings for sugar. Some poking around reveals that the answer is yes. A study in the open access journal BMC Biology in 2005 found that rats who were stressed wanted to wolf down lots of sugar cubes because of high brain levels of a chemical called corticotropin-releasing factor -- a stress hormone that humans also have. The scientists concluded that stressed people might be more likely to crave things that made them feel good - like eating sugar or taking drugs. © 2009 Discovery Communications, LLC.

Keyword: Stress; Obesity
Link ID: 13455 - Posted: 06.24.2010

By ANAHAD O’CONNOR THE FACTS For people with arthritis who seek an alternative to painkillers, magnetic straps and bracelets have become a popular option. The devices are said to work by stimulating the release of the body’s natural painkillers or by increasing blood flow to tissue. They are generally considered safe (if expensive), but in recent years a number of studies have found little evidence that they provide any real benefit. One that did find some benefit was published in 2004 in BMJ and involved 194 people with osteoarthritis of the hip and knee. The scientists found that subjects randomly assigned to wear a full-strength magnetic bracelet for 12 weeks had greater improvements than those wearing a dummy bracelet. But an analysis of several studies, also in 2004, found that the evidence swung against magnetic therapy for pain relief, and added that while it could not exclude “a clinically important benefit” in the treatment of osteoarthritis, more research was needed. Then, in a well-designed 16-week study published this year, British scientists compared the effects of a popular magnetic device, a weak magnetic wrist strap, a demagnetized device and a copper bracelet in people with osteoarthritis. Their findings were blunt. “Our results indicate that magnetic and copper bracelets are generally ineffective for managing pain, stiffness and physical function in osteoarthritis,” they concluded. THE BOTTOM LINE The evidence supporting magnetic therapy for arthritis pain is limited. Copyright 2009 The New York Times Company

Keyword: Pain & Touch
Link ID: 13454 - Posted: 06.24.2010

By RONI CARYN RABIN Many middle-aged men who have sleep apnea either do not seek treatment or are inconsistent about using the airway pressure masks prescribed to them. But what if they thought treatment might improve their golf game? Dr. Marc L. Benton, a New Jersey pulmonologist who was convinced that patients would improve their golf game if they slept better, tested his hypothesis by recruiting a dozen avid golfers with untreated sleep apnea for a small, preliminary study. Dr. Benton assessed their daytime sleepiness at the beginning of the study and recorded their golf handicap index. The patients were then fitted with nasal positive airway pressure masks and told to wear them every night. Three to five months later, after they had completed 20 new rounds of golf, the players reported using the masks up to 95 percent of the time. Compliance was also tracked electronically. The participants were less sleepy during the daytime, and their handicap index improved to 11 from an average of 12.4 before treatment, said Dr. Benton, who presented his findings last week at an international conference of the American College of Chest Physicians in San Diego. The study has not been reviewed for publication. It was limited because it was not a randomized controlled trial, and neither the patients nor the researchers were blinded about the treatment and the expected outcomes. Copyright 2009 The New York Times Company

Keyword: Sleep
Link ID: 13453 - Posted: 11.10.2009

Rex Dalton Silently slipping to 1,000 metres below the ocean surface, an undersea glider equipped with a recording device is cruising off Hawaii to capture unprecedented detail on the sounds made by whales. The experiment represents the first time that an acoustic-equipped glider has been deployed to this depth in the open ocean to record data from a specific marine mammal. Whales make distinctive clicking sounds or vocalizations both for communication and for echolocation, allowing them to navigate and forage for food, but traditional acoustic devices on the ocean surface typically can't record whale sounds emitted at lower depths. The glider is designed to collect acoustic data from beaked whales (Ziphiidae), which can dive down to 2,000 metres. These whales seem to be particularly sensitive to man-made noise, and there have been a number of beaked whale strandings associated with the use of military sonar equipment1. The data will help to improve our understanding of whale biology, researchers say, but the glider is also being considered as a more effective way of monitoring marine mammals when airguns are deployed for seismic studies of the seafloor (see 'Airgun ban halts seismic tests'). Such tests have been linked to whale strandings or deaths, but when observers try to monitor whales by sight during the studies, "they miss about 85% of the whales present," says whale-acoustics expert Dave Mellinger of Oregon State University's Hatfield Marine Science Center in Newport, Oregon, who works on the glider project. © 2009 Nature Publishing Group

Keyword: Animal Communication; Hearing
Link ID: 13452 - Posted: 06.24.2010

By Patricia Wen Pity the Boston car salesman who negotiated across the table from Charles A. Nelson III, a Harvard neuroscience professor who runs the nation’s top laboratory studying how people learn to decode facial expressions. As the two men faced off in the showroom last month, the salesman insisted to Nelson that he had just offered the absolute lowest price for the German car in question, declaring, “This is it.’’ Then the salesman’s eyes darted to a vacant corner, his nose and mouth taking on a configuration that shouted “Bluff.’’ The professor ultimately left the dealership smiling, holding a contract to buy the car at a far lower price, a bargain in his estimation. Such is one ancillary benefit of Nelson’s exhaustive research, which unfolds every day in his $1.5 million cognitive neuroscience laboratory at Children’s Hospital Boston, where he studies just when and how humans learn to read faces. To that end, his lab recruits hundreds of babies and preschoolers from the Boston area, with staff members making pitches at day care centers and children’s fairs. Using high-tech equipment to monitor the children’s eye movements and brain activity, researchers seek to discover how people identify one face from another and how they decipher the emotions behind particular expressions. © 2009 NY Times Co

Keyword: Emotions; Development of the Brain
Link ID: 13451 - Posted: 06.24.2010

By BENEDICT CAREY It’s snowing heavily, and everyone in the backyard is in a swimsuit, at some kind of party: Mom, Dad, the high school principal, there’s even an ex-girlfriend. And is that Elvis, over by the piñata? Dreams are so rich and have such an authentic feeling that scientists have long assumed they must have a crucial psychological purpose. To Freud, dreaming provided a playground for the unconscious mind; to Jung, it was a stage where the psyche’s archetypes acted out primal themes. Newer theories hold that dreams help the brain to consolidate emotional memories or to work though current problems, like divorce and work frustrations. Yet what if the primary purpose of dreaming isn’t psychological at all? In a paper published last month in the journal Nature Reviews Neuroscience, Dr. J. Allan Hobson, a psychiatrist and longtime sleep researcher at Harvard, argues that the main function of rapid-eye-movement sleep, or REM, when most dreaming occurs, is physiological. The brain is warming its circuits, anticipating the sights and sounds and emotions of waking. Drawing on work of his own and others, Dr. Hobson argues that dreaming is a parallel state of consciousness that is continually running but normally suppressed during waking. The idea is a prominent example of how neuroscience is altering assumptions about everyday (or every-night) brain functions. Copyright 2009 The New York Times Company

Keyword: Sleep
Link ID: 13450 - Posted: 06.24.2010

By NATALIE ANGIER We’ve all heard the story of the third Little Pig, who foiled the hyperventilating wolf by building his house out of bricks, rather than with straw or sticks as his brothers had done. Less commonly known is that the pig later improved his home’s safety profile by installing convex security mirrors at key points along the driveway. Well, why not? In the current issue of Animal Behaviour, researchers present evidence that domestic pigs can quickly learn how mirrors work and will use their understanding of reflected images to scope out their surroundings and find their food. The researchers cannot yet say whether the animals realize that the eyes in the mirror are their own, or whether pigs might rank with apes, dolphins and other species that have passed the famed “mirror self-recognition test” thought to be a marker of self-awareness and advanced intelligence. To which I say, big squeal. Why should the pigs waste precious mirror time inspecting their teeth or straightening the hairs on their chinny-chin-chins, when they could be using the mirror as a tool to find a far prettier sight, the pig heaven that comes in a bowl? The finding is just one in a series of recent discoveries from the nascent study of pig cognition. Other researchers have found that pigs are brilliant at remembering where food stores are cached and how big each stash is relative to the rest. They’ve shown that Pig A can almost instantly learn to follow Pig B when the second pig shows signs of knowing where good food is stored, and that Pig B will try to deceive the pursuing pig and throw it off the trail so that Pig B can hog its food in peace. Copyright 2009 The New York Times Company

Keyword: Intelligence; Evolution
Link ID: 13449 - Posted: 06.24.2010

A small microscope that can be mounted on an animal's head should offer a front-row view of how its brain processes visual and other stimuli on the move. A laser inside the device scans the activity of neurons through a tiny hole in the skull, made prior to the experiment under anaesthetic. When the microscope was attached to freely moving rats looking at screens, it produced images of brain cells that had been labelled with a fluorescent dye. Compared with previous methods – which require restraining animals and inserting electrodes – this technique is much less invasive, revealing brain activity in animals that are moving and interacting with their environment in a more natural way. It was developed at the Max Planck Institute for Biological Cybernetics in Tübingen, Germany. Journal reference: Proceedings of the National Academy of Sciences, DOI: 10.1073/pnas.0903680106 © Copyright Reed Business Information Ltd.

Keyword: Brain imaging
Link ID: 13448 - Posted: 06.24.2010

By Cassandra Willyard If you're constantly starting new diets, then breaking them, you may have more in common with a drug addict than you know. A new study suggests that yo-yo dieters experience the same stressful pangs of withdrawal when they go on a diet that addicts experience when they go cold turkey. The idea that bad food can be addictive is not new. But previous studies have tended to focus on the positive reinforcement side of the equation--for example, the pleasurable "rush" you get from eating chocolate cake. "This is just part of the story," says Pietro Cottone, a neuroscientist at Boston University and a co-author of the new study. The brain also has a negative reinforcement system that causes anxiety and stress during withdrawal. Rather than doing drugs for the rush, he says, addicts do drugs to relieve the stress associated with withdrawal. Dieters often follow the same pattern of abstinence and relapse as drug addicts, so Cottone and his colleagues wanted to see whether the same brain circuitry might be involved. The researchers gave one group of rats unlimited access to regular rat food for 5 days, followed by 2 days of sugary, chocolate-flavored rat chow. ("They like it a lot," says Cottone.) The team repeated this cycle for 7 weeks and compared the rats' food intake and behavior with that of a control group of rats that had access only to standard chow. The control rats ate roughly the same amount of food every day, but the rats in the experimental group did not: When the junk food arrived, they pigged out. By the fifth week, the experimental rats were eating roughly 20% more food when they had access to chocolate chow than rats in the control group ate. And when it was replaced with normal food, they ate less normal food, approximately 30% less by week 5. As the study progressed, the effect became stronger. What's more, the rats going through chocolate-chow withdrawal spent less time in the exposed parts of a specially designed maze, a measure of increased anxiety. When the chocolate chow was returned, the anxiety disappeared. © 2009 American Association for the Advancement of Science

Keyword: Drug Abuse; Obesity
Link ID: 13447 - Posted: 06.24.2010

Your ability to make sense of Groucho's words and Harpo's pantomimes in an old Marx Brothers movie takes place in the same regions of your brain, says new research funded by the National Institute on Deafness and Other Communication Disorders (NIDCD), one of the National Institutes of Health. In a study published in this week's Early Edition of Proceedings of the National Academy of Sciences (PNAS), researchers have shown that the brain regions that have long been recognized as a center in which spoken or written words are decoded are also important in interpreting wordless gestures. The findings suggest that these brain regions may play a much broader role in the interpretation of symbols than researchers have thought and, for this reason, could be the evolutionary starting point from which language originated. "In babies, the ability to communicate through gestures precedes spoken language, and you can predict a child's language skills based on the repertoire of his or her gestures during those early months," said James F. Battey, Jr., M.D., Ph.D., director of the NIDCD. "These findings not only provide compelling evidence regarding where language may have come from, they help explain the interplay that exists between language and gesture as children develop their language skills." Scientists have known that sign language is largely processed in the same regions of the brain as spoken language. These regions include the inferior frontal gyrus, or Broca's area, in the front left side of the brain, and the posterior temporal region, commonly referred to as Wernicke's area, toward the back left side of the brain. It isn't surprising that signed and spoken language activate the same brain regions, because sign language operates in the same way as spoken language does — with its own vocabulary and rules of grammar.

Keyword: Language; Evolution
Link ID: 13446 - Posted: 06.24.2010

By Mary Bates The discovery of mirror neurons in the brains of macaques about ten years ago sent shockwaves through the neuroscience community. Mirror neurons are cells that fire both when a monkey performs a certain task and when it observes another individual performing that same task. With the identification of networks of similarly-behaving cells in humans, there was much speculation over the role such neurons might play in phenomena such as imitation, language acquisition, observational learning, empathy, and theory of mind. Several research groups have observed the activity of mirror neuron networks indirectly in humans through the use of functional magnetic resonance imaging (fMRI). This technology allows scientists to correlate changes in blood flow in specific brain areas to particular behaviors or mental operations. Experiments using fMRI have demonstrated that there is more activation in the human mirror system when people observe movements with which they are familiar; for instance, experienced dancers had larger mirror network activations when they viewed steps from their own repertoire compared to moves from a different style of dance. Studies of the human mirror system have also revealed that it can be activated by the sounds of actions alone, in the absence of any visual cues. While evidence along these lines suggests that hearing can activate mirror neurons as well as vision, it is not clear if aurally-presented stimuli evoke visual imagery that then recruits the mirror system. These studies did not address whether a functional visual system was a necessary prerequisite for the development of the mirror system. © 1996-2009 Scientific American Inc.

Keyword: Vision
Link ID: 13445 - Posted: 06.24.2010

Marcus Munafò and Jonathan Flint. During the second world war, the physicist Enrico Fermi asked General Leslie Groves of the US Army how many generals might be called "great" and why. Groves replied that any general who won five major battles in a row might be called great, and that about three in every hundred would qualify. Fermi countered that if opposing forces are roughly equal, the odds are one in two that a general will win one battle, one in four that he will win two battles in a row, one in eight for three battles, one in 16 for four battles, and one in 32 for five battles in a row. "So you are right, General, about three in a hundred. Mathematical probability, not genius."1 There's an analogue of Fermi's "great general": the "great scientific discovery", or at least, as a case study, "the great genetic scientific discovery" as reported in the press. The discovery of genes for a certain behaviour, for schizophrenia, for happiness, always get good press coverage, usually based on publication in a respected scientific journal such as Science or Nature. The research paper will include a statistic: the probability that the finding could have occurred by chance. The probability will have been sufficiently low that a reviewer for the journal was impressed and therefore recommended publication. Typically this probability or "P-value" will be less than 0.05, or 5%, which means the odds are less than one in 20 that the observed genetic correlation could have occurred by chance. © Guardian News and Media Limited 2009

Keyword: Genes & Behavior; Depression
Link ID: 13444 - Posted: 06.24.2010

Being obese as a teenager may be linked with an increased risk of multiple sclerosis as an adult, researchers say. A 40-year study of 238,000 women found those who were obese at 18 had twice the risk of developing MS compared to women who were slimmer at that age. Yet body size during childhood or adulthood was not found to be associated with MS risk, the US researchers report in Neurology. But an MS charity warned more research was needed to confirm the findings. Researchers from Harvard School of Public Health used data from nurses taking part in a large study on diet, lifestyle factors and health. Over the course of the study, 593 women were diagnosed with MS, a condition caused by the loss of nerve fibres and their protective myelin sheath in the brain and spinal cord, which causes neurological damage. The researchers compared the risk of the disease with body mass index (BMI) - a ratio of weight to height - at age 18. Participants were also asked to describe their body size using a series of diagrams at the age of five, 10 and 20. The study showed that those with an "obese" BMI of 30 or larger at age 18 had more than twice the risk of developing MS. There was also a smaller increased risk in those who were classed as overweight. The results were the same after accounting for smoking status and physical activity level. When comparing the risk of MS with self-reported body shape, the researchers found no association between childhood obesity and the future chances of developing the disease. They also found no risk associated with adult obesity. But women who had a larger body size at 20 years of age also had almost twice the risk of MS compared to women who reported a thinner body size. (C)BBC

Keyword: Multiple Sclerosis; Obesity
Link ID: 13443 - Posted: 11.09.2009

By Victoria Gill A study in mice has hinted at the impact that early life trauma and stress can have on genes, and how they can result in behavioural problems. Scientists described the long-term effects of stress on baby mice in the journal Nature Neuroscience. Stressed mice produced hormones that "changed" their genes, affecting their behaviour throughout their lives. This work could provide clues to how stress and trauma in early life can lead to later problems. The study was led by Christopher Murgatroyd, a scientist from the Max Planck Institute of Psychiatry in Munich, Germany. He told BBC News that this study went into "molecular detail" - showing exactly how stressful experiences in early life could "programme" long-term behaviour. To do this, the researchers had to cause stress to newborn mouse pups and monitor how their experiences affected them throughout their lives. "We separated the pups from their mothers for three hours each day for ten days," Dr Murgatroyd explained. "It was a very mild stress and the animals were not affected at a nutritional level, but they would [have felt] abandoned." The team found that mice that had been "abandoned" during their early lives were then less able to cope with stressful situations throughout their lives. The stressed mice also had poorer memories. Dr Murgatroyd explained that these effects were caused by "epigenetic changes", where the early stressful experience actually changed the DNA of some of the animals' genes. (C)BBC

Keyword: Development of the Brain; Stress
Link ID: 13442 - Posted: 11.09.2009