From the mammalian brain to the rock that makes up continents, scientists are trying to map the known world. And they are doing it in cooperative groups, turning science into a social event in a way unimagined by explorers of other eras. Mapping a Brain In 2003 Microsoft co-founder Paul Allen invested $100 million in a global project to locate all the genes behind the brain functions in a mouse, which has what is considered a typical mammalian brain. Scientists think mice have ninety percent of human genes, so the mouse brain is considered relevant for research on human well-being. The result has been the Allen Brain Atlas, completed last year and now posted on the Internet with open access to researchers. The atlas, an interactive database with pictures of brain sections, shows which of the 21,000 genes in mouse DNA are active—or "expressed"—in brain regions to produce various functions, such as sight, hearing, memory, or pain. The brain may be the most important object of all the mapping projects, according to Arthur W. Toga, a professor of neurology at the UCLA School of Medicine. "It all came from there," says Toga, a participant in the project. "It's the organ that allows us to create opera and great pieces of art and send a shuttle rocket to the moon." © 2007 Science & Spirit Magazine.

Keyword: Brain imaging
Link ID: 11136 - Posted: 06.24.2010

By Jessica Marshall Anyone who has ever stayed up too late and regretted it the next day knows just how much humans need sleep. Animals need it, too. Every animal studied so far—from whales to octopuses to fruit flies—sleeps, although animal sleep takes various forms, and even among mammals the human eight hours is not the norm. Horses, elephants, and giraffes, for instance, sleep only about two to four hours a day, while bats and opossums sleep up to 20. It is obvious to us what it means to be asleep, but how do scientists know whether an animal that looks asleep is doing the same thing that we are? In some cases, they can record the animals' brain waves and compare them to those of sleeping humans. But in others, scientists have settled on a few observable criteria: Is the animal in a characteristic sleep posture? Is it unresponsive? Immobile? If it is deprived of sleep, will it then sleep longer to make up for lost zzz's? Another behavioral criterion for sleep is that it is rapidly reversible, unlike hibernation, which takes a long time to enter and emerge from. Jerome Siegel, a neuroscientist at the University of California Los Angeles, says that hibernation is very much like sleep: Both help animals to conserve energy, but hibernation is more extreme. In hibernation, body temperature drops—sometimes to just a few degrees above freezing—and the brain truly shuts down, except for low-level brain activity needed to maintain functions such as breathing and circadian rhythms. Less drastic than hibernation is "shallow" torpor, in which an animal's body temperature drops, but not as low and for a shorter period of time. Some animals—like hummingbirds and hamsters—can enter and emerge from torpor daily. Copyright 2007 Friends of the National Zoo

Keyword: Sleep; Evolution
Link ID: 11135 - Posted: 06.24.2010

IMAGINE you have two candidates for a job. They are both of the same sex—and that sex is the one your own proclivities incline you to find attractive. Their CVs are equally good, and they both give good interview. You cannot help noticing, though, that one is pug-ugly and the other is handsome. Are you swayed by their appearance? Perhaps not. But lesser, less-moral mortals might be. If appearance did not count, why would people dress up for such interviews—even if the job they are hoping to get is dressed down? And job interviews are turning points in life. If beauty sways interviewers, the beautiful will, by and large, have more successful careers than the ugly—even in careers for which beauty is not a necessary qualification. If you were swayed by someone's looks, however, would that be wrong? In a society that eschews prejudice, favouring the beautiful seems about as shallow as you can get. But it was not always thus. In the past, people often equated beauty with virtue and ugliness with vice. Even now, the expression “as ugly as sin” has not quite passed from the language. There is, of course, the equally famous expression “beauty is in the eye of the beholder”, to counter it. But the subtext of that old saw, that beauty is arbitrary, is wrong. Most beholders agree what is beautiful—and modern biology suggests there is a good reason for that agreement. Biology also suggests that beauty may, indeed, be a good rule of thumb for assessing someone of either sex. Not an infallible one, and certainly no substitute for an in-depth investigation. But, nevertheless, an instinctive one, and one that is bound to redound to the advantage of the physically well endowed. © The Economist Newspaper Limited 2007.

Keyword: Sexual Behavior; Genes & Behavior
Link ID: 11134 - Posted: 06.24.2010

It makes sense to get joy out of giving to our loved ones, but we're also often generous to complete strangers. Now Claremon Graduate University neuroeconomist Paul Zak has found that dosing people with the so-called "cuddle hormone," oxytocin, makes them more generous to strangers. "I think of oxytocin as pushing on the empathy lever in the brain," Zak says. "As we push on that lever we saw this fantastic increase in generosity of real money to a complete stranger." In the experiments, college students were given ten dollars of real money they could keep, but then played a computer game in which they were asked to share some of it with a stranger. While they couldn't see or hear the stranger, the task did force them to put themselves in the strangers' place. "We said, 'If you gave money, how much would you give.?' And, "If you received it and you have a chance to reject how much you were given because it was just too stingy, how much would you accept? What's the smallest amount you would accept?'" He wrote in the journal PLoS One that subjects who got a snort of oxytocin gave 80-percent more money than those who inhaled just a saline solution. © ScienCentral, 2000-2007.

Keyword: Hormones & Behavior; Emotions
Link ID: 11133 - Posted: 06.24.2010

Forms of a gene known to increase risk for schizophrenia may create an imbalance in brain pathways for dopamine, suggests a recent study by NIMH scientists. The findings could help explain how this key chemical messenger goes awry in the disorder, which affects about one percent of adults. It has long been known that dopamine is overactive in schizophrenia and that some antipsychotic medications work by blocking the D2 subtype of dopamine receptor on neurons. Geneticist Richard Straub, Ph.D., and colleagues in the NIMH Genes, Cognition and Psychosis Program, sought a mechanism for how a gene implicated in the illness might affect the number or sensitivity of D2 receptors. Reported online November 7, 2007 in the Journal of Neuroscience, their findings hint at a genetically-influenced imbalance between the pathways mediating D2 and D1 dopamine receptors in schizophrenia. Straub and colleagues had earlier linked to schizophrenia certain versions of a gene that results in reduced levels of a protein called dysbindin, which is involved in communications between brain cells. But how dysbindin might relate to dopamine remained a mystery. Copyright 2004-2007 eMaxHealth.com

Keyword: Schizophrenia; Genes & Behavior
Link ID: 11132 - Posted: 12.24.2007

The Associated Press U.S. health officials say improper use of patches that emit the painkiller fentanyl is still killing people. Today's warning from the U.S. Food and Drug Administration is the second concerning the powerful narcotic in two years. The FDA blames some of the deaths on the patches being improperly prescribed to certain patients. Fentanyl should be used to control chronic pain in people already used to narcotics, such as some cancer patients. Yet the FDA has found cases where doctors prescribed it for headaches or post-surgical pain. Authorities said patients also are accidentally overdosing by putting on more of the patches than prescribed, replacing them too frequently or getting them too hot. The earlier warning in 2005 noted 120 deaths among users. The FDA did not say how many more deaths it has learned of since then. In 2005, Health Canada issued a warning about the pain patch Duragesic, which contains fentanyl. It recommended the patch be used only in adults for the "management of persistent, moderate to severe chronic pain that cannot be managed by lesser means." © The Canadian Press, 2007

Keyword: Pain & Touch
Link ID: 11131 - Posted: 06.24.2010

Health Canada has issued a warning about serious skin and allergic reactions related to Alertec, a drug used to relieve excessive sleepiness due to narcolepsy, obstructive sleep apnea and shift-work sleep disorders. The federal agency said patients taking Alertec (modafinil) should seek immediate medical attention if they have any of the following symptoms: skin rash, hives, sores in the mouth, blisters and skin peeling; swelling of the face, eyes, lips, tongue or throat; trouble swallowing or breathing; or a hoarse voice. Alertec, made by Shire Canada Inc., is not approved in Canada for use in children for any condition. The drug can cause mental problems, such as depression, anxiety, hallucinations, mania and suicidal thoughts, although these events were rare during controlled studies. Health Canada says anyone experiencing such psychiatric conditions should stop taking Alertec and seek medical attention. Those taking the drug should tell their doctor if they have any heart problems, chest pain, have had a heart attack or a history of psychiatric disorders. © The Canadian Press, 2007

Keyword: Narcolepsy; Sleep
Link ID: 11130 - Posted: 06.24.2010

Brian Vastag About half of all depressed people who take standard antidepressant drugs fail to improve. Some suffer unpleasant side effects and abandon the medicines, while others simply don't feel better. Commercial tests claim to predict, by a genetic analysis, how well individual patients will fare on different antidepressants, but a panel convened by the Centers for Disease Control and Prevention (CDC) in Atlanta now says that the tests don't work as advertised. The panel "discourages" use of such tests until further studies clarify their value, according to a statement the group published in the December Genetics in Medicine. "That isn't to say that eventually there won't be a role for these tests. We just don't know what that role is yet," says panel member Joan Scott of the Genetics and Public Policy Center in Washington, D.C. The tests scan a person's DNA for variations in genes for two key liver enzymes. These enzymes break down selective serotonin reuptake inhibitors (SSRIs), a standard class of antidepressants that includes fluoxetine (Prozac) and nearly a dozen other drugs. Variations in the two enzymes affect how quickly different people clear SSRIs from their blood, which in turn influences the drugs' effectiveness. ©2007 Science Service

Keyword: Depression; Genes & Behavior
Link ID: 11129 - Posted: 06.24.2010

(HealthDay News) -- Developmental problems involving a walnut-shaped part of the brain called the amygdala -- linked to fear, anxiety and other emotions -- may explain why mental illness and addiction often appear together, researchers say. Many kinds of addiction -- such as those for alcohol, drugs and nicotine -- occur in people with various kinds of mental illness, including depression, schizophrenia and anxiety disorders, according to background information in an American Psychological Association news release about the Indiana University study. Two to five of every 10 anxious or depressed people, and four to eight of every 10 people with schizophrenia, biopolar disorder or antisocial personality, also have some form of addiction, according to epidemiological data. In this study, published in the December issue of Behavioral Neuroscience, the researchers compared the behavior of adult rats whose amygdalas were surgically damaged in infancy and adult rats with intact amygdalas. Rats with the damaged amygdalas showed less fear and caution than normal and were significantly more sensitive to cocaine after just one exposure to the drug. Rats with damaged amygdalas that received repeated cocaine injections developed "even stronger expressions of the enduring changes in behavior -- suggesting an overall hypersensitivity to the addictive process," the researchers noted. © 2007 Forbes.com LLC™

Keyword: Drug Abuse; Schizophrenia
Link ID: 11128 - Posted: 06.24.2010

For people in their 60s, regular walking appears to lower the risk of dementia. The finding, published this week in the medical journal Neurology, is the latest study to show that exercise helps delay some of the worst ravages of aging for both the body and the mind. The recent research tracked the exercise habits of 749 men and women in Italy who were over age 65 and were in good health, with no indication of memory problems at the beginning of the study. After four years, they found that the most-frequent walkers had a 27 percent lower risk for developing vascular dementia than those people who walked the least. What’s important about the study is that it again shows exercise doesn’t have to be excruciating to reap the benefits. “It’s important to note that an easy-to-perform moderate activity like walking provided the same cognitive benefits as other, more demanding activities,” said study author Dr. Giovanni Ravaglia of University Hospital S. Orsola Malpighi, in Bologna, Italy. Last year, the Annals of Internal Medicine reported on a study of more than 1,700 adults over 65 that also showed regular walkers have lower dementia risk. In that study, walkers who exercised three or more times a week showed a dementia risk of 13 per 1,000 person years, but the adults who walked less often had a risk of 19.7 per 1,000 person years. That translates to a nearly 40 percent reduction in risk. Copyright 2007 The New York Times Company

Keyword: Alzheimers
Link ID: 11127 - Posted: 06.24.2010

Men are naturally more comedic than women because of the male hormone testosterone, an expert claims. Men make more gags than women and their jokes tend to be more aggressive, Professor Sam Shuster, of Norfolk and Norwich University Hospital, says. The unicycling doctor observed how the genders reacted to his "amusing" hobby. Women tended to make encouraging, praising comments, while men jeered. The most aggressive were young men, he told the British Medical Journal. Previous findings have suggested women and men differ in how they use and appreciate humour. Women tend to tell fewer jokes than men and male comedians outnumber female ones. Research suggests men are more likely to use humour aggressively by making others the butt of the joke. And aggression - generally considered to be a more masculine trait - has been linked by some to testosterone exposure in the womb. Professor Shuster believes humour develops from aggression caused by male hormones. He documented the reaction of over 400 individuals to his unicycling antics through the streets of Newcastle upon Tyne. Almost half of people responded verbally - more being men. Very few of the women made comic or snide remarks, while 75% of the men attempted comedy - mostly shouting out "Lost your wheel?", for example. (C)BBC

Keyword: Hormones & Behavior; Emotions
Link ID: 11126 - Posted: 12.21.2007

CHICAGO - Children who have long, frequent or aggressive temper tantrums may be at risk of depression or disruptive disorders, U.S. researchers said on Thursday. They said tantrums were often the sign of a sick, hungry or overstimulated child. For most parents, they were a normal part of development and should be viewed as a teaching opportunity. But parents of children who hurt themselves or others and those who cannot calm themselves without help should seek medical help, they found. Healthy children tended to have less aggressive, and generally shorter tantrums. “I think parents to some degree should expect their children to have tantrums,” said Dr. Andy Belden of Washington University School of Medicine in St. Louis, whose study appeared in the Journal of Pediatrics. “If they are having extreme tantrums consistently. If almost every time they are having a tantrum they are hurting themselves or other people, that is a valid reason to go and talk to your pediatrician,” Belden said in a telephone interview. Copyright 2007 Reuters

Keyword: Development of the Brain; Depression
Link ID: 11125 - Posted: 06.24.2010

By Nikhil Swaminathan A new discovery about the function of neurons could help scientists understand how the brain assembles information during learning and memory formation. Scientists have found that when electrical impulses are passed from one neuron to another, they not only strengthen the synapse (connection) between them, but they also give a boost to neighboring synapses, priming them to learn more quickly and easily. Researchers report in Nature that the extra kick, which lasts from five to 10 minutes, may be key to memory formation. The residual effect "had been predicted based on so-called classic models of plasticity"—the ability of the brain to adapt by strengthening or weakening connections between neurons—but had not previously been proved, says study co-author Karel Svoboda, a biophysics group leader at the Howard Hughes Medical Institute's Janelia Farm Research Campus in Ashburn, Va. "You'd like to have clustered plasticity of this sort" to keep memories grouped together. Neurons, or nerve cells, each have a pair of projections—the axon and the dendrite, which transmit and receive impulses, respectively. The dendrite, a treelike structure, has several branches dotted with hundreds synaptic receiving terminals called "spines," each connected to the axons of scores of other neurons. When one of these spines receives stimulation (through the synapse it creates with another cell's axonal projection), the spine expands into the synapse, strengthening the link between its neuron and the other cell. This process of enhanced communication through a synapse is called long-term potentiation (LTP) and is thought to be the basis of learning. © 1996-2007 Scientific American Inc.

Keyword: Learning & Memory
Link ID: 11124 - Posted: 06.24.2010

Matt Kaplan Birds that sing in harmonious duets with one another have always been considered monogamous partners, with the singing thought to help in building faithful relationships. Now, research has shown at least that one such species sleeps around. Lauryn Benedict of the Museum of Vertebrate Zoology at the University of California, Berkeley, studied duetting California towhees (Pipilo crissalis ). She found that although female birds sang with the same male every day, more than one-quarter of their chicks were not fathered by her ‘husband’. “I’ve never caught a female in the act of cheating, they’re very secretive about their trysts,” says Benedict. But the duetting pairs copulate regularly together, she says. Ornithologists "perceived the beautiful harmonies of these birds as creating a sense of fidelity, but I suspected we were missing something”, says Daniel Mennill of the University of Windsor in Ontario. It’s uncertain whether the males in the pairs are also cheating, or how they would react if they caught their partner sneaking around. In the reed bunting (Emberiza schoeniclus ) and a few other bird species, the male feeds the young less often if it suspects the female of cheating, presumably because he knows the kids might not be his, says Benedict. © 2007 Nature Publishing Group

Keyword: Sexual Behavior; Language
Link ID: 11123 - Posted: 06.24.2010

Women with severe premenstrual syndrome (PMS) may have a permanently depressed nervous system, research suggests. A Japanese team found that PMS was tied to decreased activity in the autonomic nervous system - which controls the body's equilibrium - each month. The effect was most pronounced in women with the most severe, and potentially debilitating, PMS symptoms. The study, by Osaka's International Buddhist University, appears in the journal BioPsychoSocial Medicine. For some women PMS is a minor monthly annoyance, but for others, more severe symptoms seriously disrupt their lives. It is known that the condition is linked to hyper-sensitivity to the hormone progesterone, which is released by the body after ovulation. However despite the number of women affected, science has yet to offer a full explanation or universal treatment. The Japanese team measured heart rate variability and hormone levels in 62 women, and also used questionnaires to evaluate physical, emotional and behavioural symptoms. They found that women troubled by PMS showed decreased nervous activity in the late luteal phase, which precedes menstruation. Those with the most marked symptoms - known as premenstrual dysphoric disorder (PMDD) - had lower rates of nerve activity than the other groups during the entire menstrual cycle. Researcher Dr Tamaki Matsumoto said the underlying biological mechanism of PMS remained unclear. (C)BBC

Keyword: Hormones & Behavior
Link ID: 11122 - Posted: 12.20.2007

Brendan Maher Researchers have reversed almost all symptoms of fragile-X syndrome in a mouse model for the disease. In humans, fragile X is the most common form of heritable mental retardation and one of the leading known causes of autism. The findings, published today in Neuron, add to evidence suggesting a cause of fragile X defects — with possible therapeutic implications. Mouse studies could translate to help for humans with Fragile X.Getty“I think it’s an exciting set of findings that indicates a clear route to attempt treatment for a significant set of fragile-X symptoms,” says Thomas Jongens, a neurogeneticist at the University of Pennsylvania School of Medicine in Philadelphia, who was not involved in the research. Male mice have only one copy of the gene that encodes the fragile-X mutant related protein FMRP, which is — as its name suggests — mutated in the disease. When this gene is knocked out, the males produce a useful, if imperfect, model for the human disease. A team led by Mark Bear, director of the Picower Institute for Learning and Memory at the Massachusetts Institute of Technology in Cambridge, crossed these mice with other mice lacking a copy of a specific receptor protein called mGluR5. Earlier work had suggested that overproduction of mGluR5 could be responsible for fragile X defects. © 2007 Nature Publishing Group

Keyword: Development of the Brain; Genes & Behavior
Link ID: 11121 - Posted: 06.24.2010

Jennifer Viegas, -- People aren't the only primates who will pay for sex, new research shows. Male longtailed macaques exchange grooming for the right to mate with females whose fur they cleaned. The findings, which have been accepted for publication in the journal Animal Behavior, present the first evidence that a "social market" influences sexual interaction in a non-human primate. "I found that the amount of grooming a male performs on a female during a sexual interaction is related to the supply/demand ratio of females per male around the male-female pair at the time of the grooming," explained Michael Gumert, who conducted the research. Put another way, male monkeys -- especially lower status ones -- have to groom more to get more action when fewer females are around. Grooming in macaques involves using the teeth and hands to pick through the fur of the recipient to remove dirt, tangles and parasites. The activity often sexually excites the monkeys, particularly the males, so many scientists suspect it evolved into foreplay in humans. © 2007 Discovery Communications, LLC

Keyword: Sexual Behavior
Link ID: 11120 - Posted: 06.24.2010

Heidi Ledford Stimulating just one neuron can be enough to affect learning and behaviour, researchers have found. The results, published this week by Nature, conflict with the long-held notion that many neurons — in the order of thousands — are required to generate a behavioural reaction. The findings lend support to the ‘sparse-coding’ hypothesis of neural networks, which suggests that only a few neurons need to fire to generate a response. That theory has been hotly debated, says Karel Svoboda, a neurobiologist at the Janelia Farm research campus at Howard Hughes Medical Institute in Ashburn, Virginia, and one of the study's authors. “There are lots of fights about whether or not neural codes are sparse,” he says. Svoboda and his colleagues, as well as an independent group of researchers lead by Michael Brecht of the Humboldt University in Berlin, Germany, tackled the debate by studying the region in the rodent brain that receives sensory inputs from the whiskers. That region, called the barrel cortex, is made up of roughly two million neurons. Each whisker transmits signals to a group of cells clustered in the barrel-shaped arrangement that gives the region its name. © 2007 Nature Publishing Group

Keyword: Pain & Touch; Development of the Brain
Link ID: 11119 - Posted: 06.24.2010

CHICAGO - Nerves that sense the icy slap of an arctic wind or just a cool breeze take their orders from a single protein, U.S. researchers said on Monday, shedding new light on how we experience cold. Prior studies have suggested cold-sensing neurons are specialized, with some detecting painful cold sensations and others detecting more pleasant ones. But researchers at the University of Southern California have found that even though most cold-sensing neurons make use of a single protein known as TRPM8, they can detect a range of sensations. “We all know when we stimulate our teeth with cold we get this distinct cold sensation,” said David McKemy, whose study appears in the Journal of Neuroscience. “You get this sharp transient shooting pain and this dulled, aching sensation,” McKemy said in a telephone interview. Other groups have attributed that to two different cold sensory neurons. “There was a notion that there were neurons called cool fibers and there were others involved in detecting cold pain,” he said. He said he had expected neurons that express, or produce, TRPM8 to be of the pleasant cool variety. Copyright 2007 Reuters

Keyword: Pain & Touch
Link ID: 11118 - Posted: 06.24.2010

Inhaled cannabis smoke has more harmful toxins than tobacco, scientists have discovered. The Canadian government research found 20 times as much ammonia, a chemical linked to cancer, New Scientist said. The Health Canada team also found five times as much hydrogen cyanide and nitrogen oxides, which are linked to heart and lung damage respectively. But tobacco smoke contained more of a toxin linked to infertility. Experts said users must be aware of the risks. About a quarter of the population in the UK smokes tobacco products, while a sixth of 15 to 34-year-olds have tried cannabis in the past year, making it the most commonly used drug. Previous research has shown cannabis smoke is more harmful to lungs than tobacco as it is inhaled more deeply and held in the lungs for a longer period. However, it has also been acknowledged that the average tobacco user smokes more than a cannabis user. Researchers from Health Canada, the government's health research department, used a smoking machine to analyse the composition of the inhaled smoke for nearly 20 harmful chemicals. They also looked at the sidestream smoke, given off from the burning tip of the product and responsible for 85% of the smoked inhaled through passive smoking. In most cases, the comparison on sidestream smoke broadly mirrored that of inhaled smoke. However, in the case of polycyclic aromatic hydrocarbons, the toxin linked to infertility, the researchers found concentrations were actually higher in cigarette smoke. The study also showed little difference in the concentrations of a range of chemicals, including chromium, nickel, arsenic and selenium. (C)BBC

Keyword: Drug Abuse
Link ID: 11117 - Posted: 12.19.2007