Christen Brownlee At family dinner tables around the globe, prodding mothers have dished out the same refrain for decades: "Eat your fish," they say. "It's brain food!" For children picking at crusty fish sticks or blobs of pink poached salmon, the statement raises suspicions. But the message is turning out to be more than just an attempt to get children to clean their plates. Recent research is suggesting that what you eat can influence the function of your brain. Scientists are providing hints that what you choose to consume or avoid in your daily diet can have consequences on the brain's resiliency in the face of injury or disease. Studies suggest that foods such as fish and a curry spice called curcumin, for example, can give the brain an added edge to stay healthy. On the other hand, a steady diet of high-fat and starchy foods, such as that double cheeseburger from a favorite fast-food joint, may eventually do the brain a serious disservice. On the extreme end of dieting, some research indicates that paring food intake to the bare minimum may protect the brain from a lifetime of everyday insults. Taken together, these results point in a direction that any kid could have seen coming: Once again, Mom was right. Copyright ©2006 Science Service.

Keyword: Obesity; Intelligence
Link ID: 8609 - Posted: 06.24.2010

Nathan Seppa An experimental drug for multiple sclerosis (MS) that was approved in 2004, then abruptly yanked off shelves last year because of safety concerns, may get a second chance. Two studies show that the drug can curb MS symptoms and slow progression of the autoimmune disease over 2 years, the longest tests of this drug to date. A third investigation finds no further cases of the often-fatal complication that sidetracked the drug last year, beyond the three patients who fell ill at that time. All three papers appear in the March 2 New England Journal of Medicine. The drug, natalizumab, was pulled 4 months after its approval by the Food and Drug Administration. Three patients in clinical trials had developed progressive multifocal leukoencephalopathy (PML), a rare nervous system disorder caused by a virus that attacks people with suppressed immunity. The withdrawal came after doctors had written roughly 7,000 prescriptions for natalizumab for MS, rheumatoid arthritis, and an intestinal ailment called Crohn's disease. The drug was marketed as Tysabri by Biogen Idec of Cambridge, Mass., and Elan Corp. of Dublin, which both funded the new studies testing the drug's effectiveness. Copyright ©2006 Science Service.

Keyword: Multiple Sclerosis; Neuroimmunology
Link ID: 8608 - Posted: 06.24.2010

By JONATHAN SILVERSTEIN -- Back in the ice age, Northern European cavemen got all the chicks. Thanks to a food shortage and a man shortage about 10,000 years ago, men were in such demand they had their pick of mates. With so much competition among women to find a mate, nature and evolution kicked in to give some cave women a distinctive look to attract the opposite sex: blond hair and blue eyes. So says a new study published in the British science journal Evolution and Human Behavior. The study's author, Canadian anthropologist Peter Frost, concludes that although blond hair and blue eyes started as a genetic mutation, men were pulled in by the golden locks and baby blues, thus populating the area with blond and blue-eyed children. While the rest of the world has predominantly brown hair and brown eyes, Northern Europeans have the greatest variety of hair and eye color found anywhere, and Frost believes it resulted from the sexual appeal of these traits. "When an individual is faced with potential mates of equal value, it will tend to select the one that 'stands out from the crowd,' the study said. © 2006 ABC News Internet Ventures

Keyword: Evolution; Sexual Behavior
Link ID: 8607 - Posted: 06.24.2010

By Jennifer Viegas, Discovery News — Enormous bee swarms containing as many as 15,000 bees are guided by "streaker" scout bees that fly super fast and lead the swarm to its destination, according to a new study published in the latest journal Animal Behavior. The study negates a prior theory that scout bees released smelly chemicals that informed the other bees where to go. The discovery of streaking scout bees indicates the other bees simply look up to the speedy flyers that zip along with a "Follow me!" visual cue. "A bee's eye is rather large and is not placed at the front of the bee's 'face' like ours, but is sort of positioned on top of the bee's head," explained Madeleine Beekman, lead author of the study. "This means that the bee has a clear view of what is happening above her." Beekman, a bee expert and researcher in the School of Biological Sciences at the University of Sydney, added, "Hence, when scouts fly fast above a bee that doesn't know where to go, this fast-flying bee will be visible as a streak and this streak points into the direction of travel." She told Discovery News that the streaks are even visible to humans; she has seen them by walking into bee swarms. The fastest streakers fly at a rate of around 3.3 feet per second. © 2006 Discovery Communications Inc.

Keyword: Animal Communication
Link ID: 8606 - Posted: 06.24.2010

Roxanne Khamsi A multiple sclerosis drug, voluntarily withdrawn from sale by its manufacturers following complications in patients, has shown substantial benefits in slowing the progression of the disease in a new study. Natalizumab (branded Tysabri), made by Biogen Idec and Elan Pharmaceuticals, reduced the risk of sustained progression of disability from MS by 42% in a study of about 1000 patients. Results from the two-year trial which began in 2001 and received supported by Biogen, were published in the New England Journal of Medicine on Wednesday. Natalizumab also decreased the frequency of clinical relapses, which could involve a dramatic reduction in sight or muscle function due to MS, by 68%. By comparison, current MS drugs on the market reduce these relapses by about one-third, comments Allan Ropper, at the Caritas-St. Elizabeth’s Medical Center in Boston, US, also an associate editor at NEJM. However, another study published alongside these results, following more than 3000 participants has estimated that patients treated with natalizumab have a one in 1000 chance of developing a potentially fatal disease of the central nervous system called progressive multifocal leukoencephalopathy (PML). PML, symptoms of which include mental deterioration and problems with speech, can be caused by a latent virus present in the kidneys of over 60% of people. The virus remains latent in healthy humans, but suppression of the immune system can allow it to become active and cause damage. © Copyright Reed Business Information Ltd.

Keyword: Multiple Sclerosis
Link ID: 8605 - Posted: 06.24.2010

Michael Hopkin Chimpanzees may be more eager to help than we thought. Research suggests that the apes can understand when a person is in need, and are unexpectedly willing to give aid. Researchers at the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, have shown that young chimpanzees (Pan troglodytes) will pick up a marker pen and hand it back after their keeper has 'accidentally' dropped it. The study shows that chimpanzees understand when another is in need, and can help out if they are in a position to do so, according to Felix Warneken and Michael Tomasello, who publish the research in Science1. The results are surprising because chimpanzees, although intelligent, are not regarded as being very cooperative unless they get a clear benefit. Last year, anthropologist Joan Silk of the University of California, Los Angeles, found that chimpanzees showed no preference for getting food for the group over eating solo, even when it cost them nothing (see "Chimps fall short on friendship"). So are chimps helpful or not? It is unclear, says Silk. She points out that her experiment looked at interactions between chimps, whereas the new study looked at chimps and humans. Things are further complicated by the fact that the new experiment involved interactions between young chimps, aged between three and five years, and their caregivers, who are more like parental figures. ©2006 Nature Publishing Group

Keyword: Evolution; Development of the Brain
Link ID: 8604 - Posted: 06.24.2010

Scientists say they have identified a section of the brain which, when damaged by stress hormones, can cause the onset of dementia. High levels of stress hormone have been found to shrink the anterior cingulate cortex at the centre of the brain. Researchers at the University of Edinburgh say brain scans showing a shrunken cingulate indicates you could develop Alzheimer's in the future. It is the first time the link has been found in human brains. The study's author, Dr Alasdair MacLullich said he was "very excited" by the £130,000 study's findings. "If this part of the brain is smaller then you are likely to have higher levels of stress hormone and are at higher risk of developing dementia and depression," he said. "This could be a marker, an indicator that your brain might go wrong in the future." A team of six researchers looked at stress hormone levels in 20 healthy male volunteers aged between 65 and 70 for the study. It found that people with a smaller anterior cingulate cortex had higher levels of stress hormones. Doctors have known for years that certain diseases common in ageing like Alzheimer's disease and depression can be associated with shrinkage of the brain. (C)BBC

Keyword: Alzheimers
Link ID: 8603 - Posted: 03.01.2006

by David Cohn • Some habits are hard to break. Others become addictions. The latter group could be a figment of the past thanks to a new universal addiction-blocking substance developed by an international research effort led by the University of Saskatchewan. The team created a peptide, a short chain of amino acids, from PTEN, a natural enzyme that acts on the ventral tegmental area, the reward center of the brain, where most drugs take effect. The peptide blocks the natural rewards that an addict experiences from an increase in serotonin—a neurotransmitter associated with learning, sleep and mood—when taking his or her substance of choice. The regulation of serotonin then modulates the levels of dopamine, a neurotransmitter active in the brain’s pleasure system. "Our peptide decreases the activity of dopamine neurons located in the brain region responsible for rewards," said Xia Zhang, associate professor of psychiatry at the University of Saskatchewan. The study published in the March issue of Nature Medicine found that rats given large doses of both nicotine and THC, the active ingredient in marijuana, for eight days straight would show no signs of addiction or withdrawal when treated with the peptide after their course of the illicit substance ran out. © Copyright 2006 Seed Media Group, LLC

Keyword: Drug Abuse
Link ID: 8602 - Posted: 06.24.2010

Notebook by Mick Hume TO BE HONEST, I never expected to find myself in bed with Esther Rantzen. I now discover, however, that she is a patron of Patients’ Voice for Medical Advance (until recently known as Seriously Ill for Medical Research), a fine organisation that defends animal experimentation. Which puts us on the same side on one of the most divisive issues of the day. “Whose side are you on?” is a famous slogan of the old Left-Right divide, which you don’t often hear in our age of soulless managerial politics when, as the Monty Python song predicted, accountancy really does seem to make the world go around. But there are different divisions that matter today, drawing new lines in the political and cultural sands. One such divide is embodied by two protests around animal research due to take place in Oxford tomorrow. On one side will be the usual anti-vivisection demonstration against the building of Oxford University’s biomedical research laboratory. On the other side will be a demonstration in support of the lab and animal research. It has been called by a group called Pro-Test, set up by a 16-year-old from Swindon and now run by Oxford students, that stands for “science, reasoned debate, and above all, the welfare of mankind” (www.pro-test.org.uk). Neither of these is likely to be a mass demo. But the clash does symbolise something bigger, and to declare which side you are on is to make a statement about the sort of world in which you want to live. Copyright 2006 Times Newspapers Ltd.

Keyword: Animal Rights
Link ID: 8601 - Posted: 06.24.2010

By Katherine Unger WASHINGTON, D.C.--Teetotalers, rejoice. Toasting with grape juice may carry brain-sparing benefits, according to research presented here 24 February at the World Parkinson's Congress. In a series of cognitive and motor tests, grape juice-drinking rats outshined their placebo-swilling counterparts, possibly due to an enhanced release of the neurotransmitter dopamine in the brain. As many oenophiles are well aware, studies have found that drinking wine lowers the risk of heart disease, possibly by reducing blood pressure or countering the effects of "bad" (LDL) cholesterol. Similar effects have been shown for the dark purple Concord grape juice, which contains polyphenols, a class of antioxidants found in wines. But neuroscientist James Joseph of Tufts University in Boston, Massachusetts, and colleagues wanted to see if the compounds in grape juice might also serve to protect or preserve the brain--specifically, the elderly brain. So Joseph's group focused on 19 month- old rats--pretty ancient considering most rats live less than two years. The researchers fed the rodents a diet consisting exclusively of either grape juice (10% or 50%, diluted with water) or a calorie- and flavor-matched placebo. After six weeks, the team tested the rats for motor skills such as balance, stamina, and strength. Rats on the 50% juice diet outperformed those on either the 10% juice diet or the placebo diet; they were able to hang onto a wire for an average 2 seconds longer than the others, for example. © 2006 American Association for the Advancement of Science.

Keyword: Alzheimers; Learning & Memory
Link ID: 8600 - Posted: 06.24.2010

Researchers have identified the neural activity that occurs when the brain “sets the stage” for retaining a memory – a finding that could have important implications for memory research and help determine ways in which people can strengthen memories they want to retain while weakening ones they would rather forget. The results of the study appear as an advance online publication in the journal Nature Neuroscience. In two separate experiments with adults, UCI neuroscientist Michael Rugg, in collaboration with colleagues from University College London, looked at neural activity that preceded the presentation of single words. They found that measures of the activity could predict whether the words would be remembered in a later memory test. In the experiments, Rugg and his colleagues presented a group of young adults with a different word every four or five seconds, requiring them to make a judgment about a specific characteristic of the word, such as whether it referred to a living or a non-living thing. A moment before each word was presented, participants were “cued” with a visual signal that alerted them of the upcoming word. Neural activity caused by the cue was monitored through electroencephalograpy, or EEG, a method by which electrodes attached to the scalp measure underlying brain activity. Later, participants were shown the words again, along with words they had not previously been shown, and were asked to identify which ones had been presented in the first part of the experiment. © Copyright 2002-2006 UC Regents

Keyword: Learning & Memory
Link ID: 8599 - Posted: 06.24.2010

In addition to triggering a depression withdrawal syndrome, repeated defeat by dominant animals leaves a mouse with an enduring molecular scar in its brain that could help to explain why depression is so difficult to cure, suggest researchers funded by National Institutes of Health’s (NIH) National Institute of Mental Health (NIMH). In mice exposed to this animal model of depression, silencer molecules turned off a gene for a key protein in the brain’s hippocampus. By activating a compensatory mechanism, an antidepressant temporarily restored the animals’ sociability and the protein’s expression, but it failed to remove the silencers. A true cure for depression would likely have to target this persistent stress-induced scar, say the researchers, led by Eric Nestler, M.D., The University of Texas Southwestern Medical Center, who report on their findings online in Nature Neuroscience during the week of February 26, 2005. “Our study provides insight into how chronic stress triggers changes in the brain that are much more long-lived than the effects of existing antidepressants,” explained Nestler. In the study, mice exposed to aggression by a different dominant mouse daily for 10 days became socially defeated; they vigorously avoided other mice, even weeks later. Expression of a representative gene in the hippocampus, a memory hub implicated in depression, plummeted three-fold and remained suppressed for weeks.

Keyword: Depression
Link ID: 8598 - Posted: 06.24.2010

A team led by Massachusetts General Hospital (MGH) researchers has found that a delayed-release stimulant used to treat attention-deficit hyperactivity disorder (ADHD) may be less likely to be abused than other stimulant drugs. Study participants taking therapeutic oral doses of Concerta, a once-daily form of the drug methylphenidate, did not report perceiving and enjoying the drug's subjective effects, features that are associated with a medication's potential for abuse. The report appears in the March 2006 issue of The American Journal of Psychiatry. "We know that drugs that cause euphoria are potentially abusable, and euphoria requires rapid delivery to the brain. Using sophisticated PET scan imaging, we were able to examine the rate of delivery of both rapid- and delayed-release formulations of methylphenidate and correlate those results with how the drugs felt to study volunteers," says Thomas Spencer, MD, of the MGH Pediatric Psychopharmacology Unit, the paper's lead author. "The ability to show that rate of brain delivery may determine abuse potential is important to our understanding of the safety of different formulations." Methylphenidate and other stimulant drugs used to treat ADHD act by blocking the dopamine transporter, a molecule on brain cells that takes up the neurotransmitter dopamine, raising its level in the brain. Studies have shown that the brains of ADHD patients have abnormal regulation of dopamine, which plays a key role in the control of movement, behavior and attention. While stimulants are effective for controlling ADHD symptoms, the drugs are also subject to abuse, so the current study was designed to compare the abuse potential of two formulations of methylphenidate.

Keyword: ADHD; Drug Abuse
Link ID: 8597 - Posted: 03.01.2006

Being born very premature can affect a child's personality into adulthood, a study has suggested. Researchers from the Institute of Psychiatry studied 18 and 19-year-olds who had been born early, and compared them to those born at full-term. Premature babies, particularly girls, were found to be more likely to be anxious and withdrawn, and potentially at a higher risk of depression. The study is published in the American journal Pediatrics. The researchers assessed 108 young adults who had been born before 33 weeks gestation between 1979 and 1981. They were then compared with 67 people of the same age who were born at full-term. Everyone was asked to complete a personality questionnaire, which included 48 questions such as 'does your mood ever go up or down?' and 'do you enjoy co-operating with others?'. The results suggested those born prematurely had lower levels of a personality trait called 'extraversion', indicating that they may have less confident and outgoing personalities. They also had higher levels of the personality trait 'neuroticism', which indicates increased anxiety, lower mood and lower self-esteem. Girls' personalities were more likely to be affected by being born early. (C)BBC

Keyword: Development of the Brain
Link ID: 8596 - Posted: 02.28.2006

ST. LOUIS PARK, Minn. (AP) -- Don Falk stretched his right arm over his head, past the faint marks where a surgeon sank two wires deep in his brain, to show how uncontrollable tremors in his hand used to slap him awake in the morning. It was just one of many difficulties he suffered as his Parkinson's disease advanced. Falk had trouble shaving and walking, and his medications caused his head to twitch awkwardly, making him self-conscious in church. ''It's the day-to-day living that is so hard with Parkinson's,'' he said. In May, Falk, 52, started to get better with the help of an emerging class of implantable medical devices called neuromodulators -- tiny machines that stimulate the central nervous system to treat a host of disorders. Analysts say they could be the next big thing for some of the market's hottest medical technology companies. Of course, the same hurdles that have stood in the way of other medical technologies will have to be overcome, including getting government approvals, securing adequate insurance reimbursements and persuading busy doctors to learn to use the devices. Copyright 2006 The Associated Press

Keyword: Parkinsons
Link ID: 8595 - Posted: 02.28.2006

By Jennifer Viegas, Discovery News — Expectant fathers within at least two primate species gradually gain weight during the course of their mate's pregnancy, a new study has found. Researchers observed this classic female pregnancy symptom in common marmoset (Callithrix jacchus) and cotton-top tamarin (Saguinus oedipus) male primates. The scientists suspect that males in most monogamous primates, including gibbons, some lemurs species and humans, also show signs of pregnancy when their mates are expecting. While the new study represents the first evidence for gradual weight gain in non-human primate expectant fathers, earlier research found that between 11 and 65 percent of all human fathers have experienced some symptoms of pregnancy. The symptoms include weight gain, nausea, headaches, irritability, restlessness, backaches, colds, nervousness and hormonal changes, such as higher levels of the stress-fighting hormone cortisol and the strength-boosting hormone testosterone. Previously it was thought that these were just psychosomatic symptoms. For many such dads, however, it is likely that the changes help them to cope with the rigors of fatherhood once the baby is born. This is particularly important for the doting, yet squirrel-sized, marmoset and tamarin dads, whose job includes toting around their often hefty babies. Copyright © 2006 Discovery Communications Inc.

Keyword: Sexual Behavior; Hormones & Behavior
Link ID: 8594 - Posted: 06.24.2010

Toni Baker A compound found in marijuana won’t make you high but it may help keep your eyes healthy if you’re a diabetic, researchers say. Early studies indicate cannabidiol works as a consummate multi-tasker to protect the eye from growing a plethora of leaky blood vessels, the hallmark of diabetic retinopathy, says Dr. Gregory I. Liou, molecular biologist at the Medical College of Georgia. “We are studying the role of cannabinoid receptors in our body and trying to modulate them so we can defend against diabetic retinopathy,” Dr. Liou says. Diabetic retinopathy is the leading cause of blindness in working-age adults and affects nearly 16 million Americans. High glucose levels resulting from unmanaged diabetes set in motion a cascade ultimately causing the oxygen-deprived retina to grow more blood vessels. Ironically, the leaky surplus of vessels can ultimately destroy vision. Dr. Liou, who recently received a $300,000 grant from the American Diabetes Association, wants to intervene earlier in the process, as healthy relationships inside the retina first start to go bad. Copyright Medical College of Georgia

Keyword: Vision; Drug Abuse
Link ID: 8593 - Posted: 06.24.2010

As much as neuroscientists know about the neural processes that signal touch, surprisingly little is understood about the neural correlates of conscious perception of tactile sensations. In a new study in the open-access journal PLoS Biology, Felix Blankenburg, Jon Driver, and their colleagues turn to a classic somatosensory illusion--called the cutaneous rabbit--that is perfectly suited to decoupling real and illusory touch. In the illusion, a rapid succession of taps is delivered first to the wrist and then to the elbow, which creates the sensation of intervening taps hopping up the arm (hence the illusion's name), even when no physical stimulus is applied at intervening sites on the arm. Blankenburg et al. took advantage of this somatosensory illusion to investigate which brain regions play a role in illusory tactile perceptions. Previous studies had implicated the somatosensory cortex--the region of the cortex that first receives input from sensors in the body--in the rabbit illusion, but did not directly test this possibility. To do this, the authors used state-of-the-art functional magnetic resonance imaging technology (called 3T fMRI) to scan the brains of people experiencing the illusion. With the enhanced image quality and resolution of this scanner (deriving from the stronger magnetic field plus a specially customized imaging sequence), the authors show that the same brain sector is activated whether the tactile sensation is illusory or real.

Keyword: Pain & Touch
Link ID: 8592 - Posted: 02.28.2006

Thanks to my new best friend, US District Judge John Jones, public school science teachers in Dover, Pennsylvania may have some space to fill in their lesson plans. In December, in a triumph for sanity over “inanity” (his word), Jones decreed that intelligent design (ID) is not science. Advocates of ID claim that certain biological structures (the eye and the blood-clotting system of humans, for example) are too complex to have arisen via evolution and must have been designed by an intelligent force at work in the universe. ID’ists are unmoved by scientists’ explanations for the step-by-step evolution of these complex structures; for their part, scientists wish that ID’ists would ditch the wishy-washy appeal to an unspecified force and “out” their God. Judge Jones sided with science. He saw ID for precisely what it is, gussied-up religious creationism, and protected young Doverites’ right to learn science in science class. But what about those gaping holes in the lesson plans? Once science teachers trot out the voyage of the Beagle, and all those Galapagos Islands’ tortoises and finches, how else to turn curious young minds toward science? By showing reruns of Gilligan’s Island, that’s how. The brilliance of this curricular innovation came to me while reading Robert Sapolsky’s essay in the John Brockman collection, Curious Minds: How a Child Becomes a Scientist. Readers of a certain age will join Sapolsky (born in 1957) and me (born in 1956) in remembering the Professor character from this show. Marooned on an island with Gilligan, Skipper, and assorted others, the Professor was a scientific know-it-all for the shipwrecked set.

Keyword: Development of the Brain; Evolution
Link ID: 8591 - Posted: 06.24.2010

by Jonah Lehrer • Posted February 23, 2006 12:37 AM Elizabeth Gould overturned one of the central tenets of neuroscience. Now she’s building on her discovery to show that poverty and stress may not just be symptoms of society, but bound to our anatomy. Professor Elizabeth Gould has a picture of a marmoset on her computer screen. Marmosets are a new world monkey, and Gould has a large colony living just down the hall. Although her primate population is barely three years old, Gould is clearly smitten, showing off these photographs like a proud parent. Marmosets are the ideal experimental animal: a primate brain trapped inside the body of a rat. They recognize themselves in the mirror, form elaborate dominance hierarchies and raise their young cooperatively. If you can look past their rodent-like stature and punkish pompadour, marmosets can seem disconcertingly human. In her laboratory at Princeton University’s Department of Psychology, Gould is determined to create a marmoset environment that takes full advantage of their innate intelligence. She doesn’t believe in metal cages. “We are housing our marmosets in large, enriched enclosures,” she says, “and with a variety of objects to support foraging. These are social animals, and it’s important to let them be social. Basically, we want to bring our experimental conditions closer to the wild.” © Copyright 2006 Seed Media Group, LLC.

Keyword: Neurogenesis
Link ID: 8590 - Posted: 06.24.2010