By Alan Mozes -- Construction foreman Jim Mueller was in his early 30s when his memory started to go. He'd forget things: his schedule, his equipment, where he was, and where he was going. Sometimes even the names of his daughters and his wife. But nothing prepared the Mueller family for the doctor's verdict. "When they said Jim had Alzheimer's, I was in shock," Jim's wife, Michelle, quietly recalls. "I mean, I had heard of Alzheimer's because of President Reagan. And I had worked at one time when I was younger to care for someone with Alzheimer's (but) I thought that was for people when they got older. And I really didn't believe it." Jim Mueller, now 39, is, in fact, just one of an estimated 500,000 Americans currently battling the daily ravages of early-onset Alzheimer's (sometimes called young-onset Alzheimer's) -- a form of the incurable and devastating neurodegenerative disease that strikes those in their mid-30s to mid-60s. For the Mueller family, the unexpected havoc wrought by Jim's Alzheimer's diagnosis at the age of 36 has turned every facet of their lives completely upside down. "It was a shock to me, too," Jim confirms. "I thought Alzheimer's, I thought gray hair. And we were just starting to get our feet wet. Just starting our family. Now we've lost everything." © 2008 Scout News LLC.

Keyword: Alzheimers
Link ID: 11512 - Posted: 06.24.2010

By SANDRA BLAKESLEE If Rod Serling were alive and writing episodes for “The Twilight Zone,” odds are he would have leaped on the true story of Anne Adams, a Canadian scientist turned artist who died of a rare brain disease last year. Trained in mathematics, chemistry and biology, Dr. Adams left her career as a teacher and bench scientist in 1986 to take care of a son who had been seriously injured in a car accident and was not expected to live. But the young man made a miraculous recovery. After seven weeks, he threw away his crutches and went back to school. According her husband, Robert, Dr. Adams then decided to abandon science and take up art. She had dabbled with drawing when young, he said in a recent telephone interview, but now she had an intense all-or-nothing drive to paint. “Anne spent every day from 9 to 5 in her art studio,” said Robert Adams, a retired mathematician. Early on, she painted architectural portraits of houses in the West Vancouver, British Columbia, neighborhood where they lived. In 1994, Dr. Adams became fascinated with the music of the composer Maurice Ravel, her husband recalled. At age 53, she painted “Unravelling Bolero” a work that translated the famous musical score into visual form. Copyright 2008 The New York Times Company

Keyword: Alzheimers
Link ID: 11511 - Posted: 06.24.2010

by Molly C. Chalfin, Katrina A. Karkazis, Emily R. Murphy 2008. The American Journal of Bioethics 8(1):1 How and why women and men are different is a topic of enduring scientific and public interest. Over the past decade, the number of neuroscience studies documenting sex differences in brain anatomy, chemistry, and function, and involving cognitive domains such as emotion, memory, and learning, has exploded (Cahill 2006). Although scholars in the field of neuroethics have explored advances in neuroscience from many angles, few, if any, have paid attention to neuroscientific work on sex differences or to gender as a primary category of analysis. Why should we pay special attention to the neuroscience of sex differences? Perhaps the most important reason is that this work will prove important for contested ideas about the so-called nature of human nature. One only need look to the Larry Summers debacle in 2005 to see how contentious the topic is and how far-reaching its effects may be. Although the question of how and why women and men are different is an old one, neuroscience's use of cutting-edge technology - coupled with a growing reliance on science to shed light on complex human behavior - increases the likelihood that this work will leap to the forefront of public discussion and debate about social equality. While neuroscience is concerned with elucidating the origin and extent of behavioral and cognitive differences between women and men, the questions that predominate for us are of a different nature: How ought we disseminate this information into a sensitive social environment that has a history of bias and discrimination against women? What are the implications of this work for our understandings of what makes us women and men? How should this research be applied in educational, medical, and legal contexts, if at all? ©2000-5 Taylor & Francis Group & bioethics education network

Keyword: Sexual Behavior
Link ID: 11510 - Posted: 06.24.2010

From The Economist print edition FASHION is a strange thing, and many fields are susceptible to it—not least, medicine. There has, for example, been a vogue (among commentators, if not among doctors) to ascribe the rising number of cases of autism diagnosed over the past couple of decades to childhood vaccinations against measles, mumps and rubella. That this is fashion rather than reality is suggested by the fact that the explanation proffered in Britain has been that such vaccines provoke an immune response that damages the nervous system, whereas Americans have blamed residual mercury in the same vaccines. It is now pretty well established that vaccination does not create autism. But the rise in the number of recorded cases is real enough. In Britain, for example, the rate of diagnosis has risen from 50 per 100,000 in 1990 to 400 per 100,000 today. That must have a cause. And one popular hypothesis is that this cause, too, is fashion—but among doctors rather than columnists. Demonstrating that has been difficult. But a paper in this month's Developmental Medicine & Child Neurology, by Dorothy Bishop and her colleagues at Oxford University, goes a long way towards doing so. Dr Bishop reasoned it was unlikely that people now labelled autistic would, in the past, have been thought healthy, but that it was quite plausible they might have been given some other diagnosis. With this in mind, she looked at a group who had been diagnosed as children with a particular condition that was not autism, and rediagnosed them using present-day criteria. © The Economist Newspaper Limited 2008

Keyword: Autism
Link ID: 11509 - Posted: 06.24.2010

By Nikhil Swaminathan Scientists for the first time have identified long-term changes in mice brains that may shed light on why addicts get hooked on drugs—in this case methamphetamines—and have such a tough time kicking the habit. The findings, reported in the journal Neuron, could set the stage for new ways to block cravings—and help addicts dry out. Researchers, using fluorescent tracer dye, discovered that mice given methamphetamines for 10 days (roughly equivalent to a human using it for two years) had suppressed activity in a certain area of their brains. Much to their surprise, normal function did not return even when the drug was stopped, but did when they administered a single dose of it again after the mice had been in withdrawal. Study co-author Nigel Bamford, a pediatric neurologist at the University of Washington School of Medicine, says that if similar changes occur in humans, it will indicate that an effective way to fight addiction may be to design therapies that target the affected area—the striatum, a forebrain region that controls movement but also has been linked to habit-forming behavior. Previous research has shown that the drug stimulates nerve cells in the midbrain to release dopamine into the synapses (connections between neurons) in the striatum. Dopamine (which is connected to reward processing, motivation and attention) is one of the brain's primary neurotransmitters, the chemical messengers by which one neuron triggers its neighbor to fire a nerve impulse. © 1996-2008 Scientific American Inc.

Keyword: Drug Abuse
Link ID: 11508 - Posted: 06.24.2010

By Constance Holden Reprogrammed body cells continue to show promise as a treatment for disease. Last year, scientists used the cells, called induced pluripotent stem (iPS) cells, to successfully treat sickle cell disease in mice (ScienceNOW, 6 December 2007). Now, investigators have shown that neurons derived from iPS cells alleviate a Parkinson's-like movement disorder in rats. A team led by Marius Wernig, a postdoc in the lab of stem cell researcher Rudolf Jaenisch at the Massachusetts Institute of Technology in Cambridge generated iPS cells from mouse tail cells by adding four genes. The researchers then differentiated the cells into neural progenitor cells using the same techniques that guide the differentiation of embryonic stem cells. When the cells were injected into the brains of fetal mice, they developed into several types of brain cells and formed connections in a half-dozen brain regions. To see whether the iPS cells could be grown into dopamine-producing neurons that could be used to treat disease, the researchers gave adult rats a Parkinson's-like movement disorder. They did this by injecting a substance that killed dopamine neurons on one side of the brain, causing the rats to move in circles. Batches of dopamine neurons grown from the mouse iPS cells were then injected into the brain area--the striatum--most stricken by Parkinson's in five rats. Within 8 weeks, four of the five treated rats showed significant recovery of function and stopped going in circles, the researchers report online today in Proceedings of the National Academy of Sciences. © 2008 American Association for the Advancement of Science.

Keyword: Parkinsons; Stem Cells
Link ID: 11506 - Posted: 06.24.2010

Randolph E. Schmid -- Dyslexia affects different parts of children's brains depending on whether they are raised reading English or Chinese. That finding, reported in Monday's online edition of Proceedings of the National Academy of Sciences, means that therapists may need to seek different methods of assisting dyslexic children from different cultures. "This finding was very surprising to us. We had not ever thought that dyslexics' brains are different for children who read in English and Chinese," said lead author Li-Hai Tan, a professor of linguistics and brain and cognitive sciences at the University of Hong Kong. "Our finding yields neurobiological clues to the cause of dyslexia." Millions of children worldwide are affected by dyslexia, a language-based learning disability that can include problems in reading, spelling, writing and pronouncing words. The International Dyslexia Association says there is no consensus on the exact number because not all children are screened, but estimates range from 8 percent to 15 percent of students. Reading an alphabetic language like English requires different skills than reading Chinese, which relies less on sound representation, instead using symbols to represent words. Past studies have suggested that the brain may use different networks of neurons in different languages, but none has suggested a difference in the structural parts of the brain involved, Tan explained. © 2008 Discovery Communications

Keyword: Dyslexia; Language
Link ID: 11505 - Posted: 06.24.2010

Coffee may cut the risk of dementia by blocking the damage cholesterol can inflict on the body, research suggests. The drink has already been linked to a lower risk of Alzheimer's Disease, and a study by a US team for the Journal of Neuroinflammation may explain why. A vital barrier between the brain and the main blood supply of rabbits fed a fat-rich diet was protected in those given a caffeine supplement. UK experts said it was the "best evidence yet" of coffee's benefits. The "blood brain barrier" is a filter which protects the central nervous system from potentially harmful chemicals carried around in the rest of the bloodstream. Other studies have shown that high levels of cholesterol in the blood can make this barrier "leaky". Alzheimer's researchers suggest this makes the brain vulnerable to damage which can trigger or contribute to the condition. The University of North Dakota study used the equivalent to just one daily cup of coffee in their experiments on rabbits. After 12 weeks of a high-cholesterol diet, the blood brain barrier in those given caffeine was far more intact than in those given no caffeine. "Caffeine appears to block several of the disruptive effects of cholesterol that make the blood-brain barrier leaky," said Dr Jonathan Geiger, who led the study. High levels of cholesterol are a risk factor for Alzheimer's disease, perhaps by compromising the protective nature of the blood brain barrier. Caffeine is a safe and readily available drug and its ability to stabilise the blood brain barrier means it could have an important part to play in therapies against neurological disorders." (C)BBC

Keyword: Drug Abuse; Alzheimers
Link ID: 11504 - Posted: 04.05.2008

Binge drinking teenagers are still at risk of absent-mindedness and forgetfulness days later, a study says. A team from Northumbria and Keele universities compared 26 binge drinkers with 34 non-bingers in memory tests, and found the drinkers fared worse. They told the British Psychological Society conference that binge drinking could be harming developing brains. A spokesman for the charity Addaction said drinking at dangerous levels was putting some young people at risk. Binge drinking is already known to affect people's memories of past events. In this study, the scientists looked at students aged 17 to 19 - a period when the brain is still developing. Binge drinking was defined as at least eight units a session for a man and six for a woman once or twice a week. The researchers said the binge drinkers studied consumed, on average, 30 units in just two sessions. The teenagers were tested three or four days after their last drinking session, so that their bodies would be free of alcohol. They were asked to answer questions about how often they forgot to carry out tasks they intended to do, such as meeting with friends. They were shown a video clip of a shopping trip after being given a couple of minutes to memorise a set of tasks prompted by various cues in the film, such as remembering to text a friend at a certain shop, or to check their bank accounts after seeing a person sitting on a bench. (C)BBC

Keyword: Drug Abuse; Learning & Memory
Link ID: 11503 - Posted: 04.05.2008

Sönke Johnsen and Kenneth J. Lohmann Like the theory of plate tectonics, the idea that animals can detect Earth's magnetic field has traveled the path from ridicule to well-established fact in little more than one generation. Dozens of experiments have now shown that diverse animal species, ranging from bees to salamanders to sea turtles to birds, have internal compasses. Some species use their compasses to navigate entire oceans, others to find better mud just a few inches away. Certain migratory species even appear to use the geographic variations in the strength and inclination of Earth's field to determine their position. But how animals sense magnetic fields remains a hotly contested topic. Whereas the physical basis of nearly all other senses has been determined, and a magnetoreception mechanism has been identified in bacteria, no one knows with certainty how any animal perceives magnetic fields. Finding this mechanism is thus the current grand challenge of sensory biology. The problem is difficult for several reasons. First, humans do not appear to have the ability to sense magnetic fields. Whereas most nonhuman senses, such as polarization detection and UV vision, are relatively straightforward extensions of human abilities, magnetoreception is not. As a result, neither intuitive understanding nor the medical literature on human senses provides much guidance. Another complicating factor is that biological tissue is essentially transparent to magnetic fields, which means that magnetoreceptors, unlike most other sensory receptors, need not be located on an animal's surface and might instead be anywhere in the body. That consideration transforms a routine two-dimensional visual inspection into a three-dimensional search requiring advanced imaging techniques. Another impediment is that large accessory structures for focusing and otherwise manipulating the field—the analogs of eardrums and lenses—are unlikely to exist because few materials of biological origin affect magnetic fields. Indeed, magnetoreception might be accomplished by a small number of microscopic, possibly intracellular structures scattered throughout the body, with no obvious structure devoted to magnetoreception. Finally, the weakness of the interaction between Earth's field and the magnetic moments of electrons and atoms, roughly one five-millionth of the thermal energy kT at body temperature, makes it difficult to even suggest a feasible mechanism. © 2007 by the American Institute of Physics

Keyword: Animal Migration
Link ID: 11502 - Posted: 06.24.2010

Dana Small, a neuroscientist at the John B. Pierce Laboratory in New Haven, Conn., and the Yale School of Medicine, sniffs out an answer. In a classic experiment, French researchers colored a white wine red with an odorless dye and asked a panel of wine experts to describe its taste. The connoisseurs described the wine using typical red wine descriptors rather than terms they would use to evaluate white wine, suggesting that the color played a significant role in the way they perceived the drink. Although sight is not technically part of taste, it certainly influences perception. Interestingly, food and drink are identified predominantly by the senses of smell and sight, not taste. Food can be identified by sight alone—we don't have to eat a strawberry to know it is a strawberry. The same goes for smell, in many cases. To our brains, "taste" is actually a fusion of a food's taste, smell and touch into a single sensation. This combination of qualities takes place because during chewing or sipping, all sensory information originates from a common location: whatever it is we're snacking on. Further, "flavor" is a more accurate term for what we commonly refer to as taste; therefore, smell not only influences but is an integral part of flavor. Pure taste sensations include sweet, sour, salty, bitter, savory and, debatably, fat. Cells that recognize these flavors reside in taste buds located on the tongue and the roof of the mouth. When food and drink are placed in the mouth, taste cells are activated and we perceive a flavor. Concurrently, whatever we are eating or sipping invariably contacts and activates sensory cells, located side-by-side with the taste cells, that allow us to perceive qualities such as temperature, spiciness or creaminess. We perceive the act of touch as tasting because the contact "captures" the flavor sensation. © 1996-2008 Scientific American Inc.

Keyword: Chemical Senses (Smell & Taste)
Link ID: 11501 - Posted: 06.24.2010

By KATE MURPHY Modern life is loud. The jolting buzz of an alarm clock awakens the ears to a daily din of trucks idling, sirens blaring, televisions droning, computers pinging and phones ringing — not to mention refrigerators humming and air-conditioners thrumming. But for the 12 million Americans who suffer from severe tinnitus, the phantom tones inside their head are louder than anything else. Often caused by prolonged or sudden exposure to loud noises, tinnitus (pronounced tin-NIGHT-us or TIN-nit-us) is becoming an increasingly common complaint, particularly among soldiers returning from combat, users of portable music players, and aging baby boomers reared on rock ’n’ roll. (Other causes include stress, some kinds of chemotherapy, head and neck trauma, sinus infections, and multiple sclerosis.) Although there is no cure, researchers say they have never had a better understanding of the cascade of physiological and psychological mechanisms responsible for tinnitus. As a result, new treatments under investigation — some of them already on the market — show promise in helping patients manage the ringing, pinging and hissing that otherwise drives them to distraction. The most promising therapies, experts say, are based on discoveries made in the last five years about the brain activity of people with tinnitus. With brain-scanning equipment like functional magnetic resonance imaging, researchers in the United States and Europe have independently discovered that the brain areas responsible for interpreting sound and producing fearful emotions are exceptionally active in people who complain of tinnitus. Copyright 2008 The New York Times Company

Keyword: Hearing
Link ID: 11500 - Posted: 06.24.2010

By NATALIE ANGIER When Jeremy Wolfe of Harvard Medical School, speaking last week at a symposium devoted to the crossover theme of Art and Neuroscience, wanted to illustrate how the brain sees the world and how often it fumbles the job, he naturally turned to a great work of art. He flashed a slide of Ellsworth Kelly’s “Study for Colors for a Large Wall” on the screen, and the audience couldn’t help but perk to attention. The checkerboard painting of 64 black, white and colored squares was so whimsically subtle, so poised and propulsive. We drank it in greedily, we scanned every part of it, we loved it, we owned it, and, whoops, time for a test. Dr. Wolfe flashed another slide of the image, this time with one of the squares highlighted. Was the highlighted square the same color as the original, he asked the audience, or had he altered it? Um, different. No, wait, the same, definitely the same. That square could not now be nor ever have been anything but swimming-pool blue ... could it? The slides flashed by. How about this mustard square here, or that denim one there, or this pink, or that black? We in the audience were at sea and flailed for a strategy. By the end of the series only one thing was clear: We had gazed on Ellsworth Kelly’s masterpiece, but we hadn’t really seen it at all. The phenomenon that Dr. Wolfe’s Pop Art quiz exemplified is known as change blindness: the frequent inability of our visual system to detect alterations to something staring us straight in the face. The changes needn’t be as modest as a switching of paint chips. At the same meeting, held at the Italian Academy for Advanced Studies in America at Columbia University, the audience failed to notice entire stories disappearing from buildings, or the fact that one poor chicken in a field of dancing cartoon hens had suddenly exploded. In an interview, Dr. Wolfe also recalled a series of experiments in which pedestrians giving directions to a Cornell researcher posing as a lost tourist didn’t notice when, midway through the exchange, the sham tourist was replaced by another person altogether. Copyright 2008 The New York Times Company

Keyword: Vision
Link ID: 11499 - Posted: 06.24.2010

Boston University Associate Dean for research, Salomon Amar has found that obese mice are not as effective as lean mice in mounting a counterattack against an infection. In research published in the Proceedings of the National Academy of Sciences, Amar found that the mice's inflammatory response, part of the body's defense against infection, was blunted. Amar fed mice a diet that was many times greater than they needed, and then infected both the now obese mice and a similar group of lean mice that grew up on a normal diet. Amar found that if a lean animal "Would take seven days to eliminate the microorganism…the obese animal would take about 10 days or 12 to 13 days." Amar also found that this reduced response had a second problem. Even though it the obese mice had a blunted inflammatory response, it lasted longer than necessary. He says, "You have to understand that the inflammatory response is very bad for the body when it stays longer. It's there to clean up the damages and then it needs to be removed." As examples, he notes that extended inflammation is an important problem for diabetics and that in some cases extended inflammation can result in fatal septic shock. Amar pointed out that in his experiments, he was able to take diabetes out of the equation by infecting the obese mouse before the onset of diabetes. The experiments were also specific to obesity caused by diet, and not some sort of genetic situation. © ScienCentral, 2000-2008

Keyword: Obesity; Neuroimmunology
Link ID: 11498 - Posted: 06.24.2010

By Elsa Youngsteadt Mice can whistle and chirp like birds--and researchers now say their songs seem to be happy ones. New experiments associate the rodents' ultrasonic chatter with the brain's dopamine-based reward system, and investigators hope that studying the songs may eventually point toward genes behind human emotional disorders such as schizophrenia and autism. Researchers have known for nearly 50 years that rodents produce ultrasonic calls. In 2005, they discovered that mice even sing complex songs (ScienceNOW, 1 November 2005). Their sparrowlike whistles and twitters are a couple of octaves too high for human ears to hear. No one knew exactly why mice sing, but rats make similar calls during sex, pleasant brain stimulation, and drug use, so psychologists thought the songs might be a sign of happiness. If this held true in mice, then powerful genetic tools available only in mouse studies could help researchers discover new genes that affect emotion and pleasure. A team of researchers led by brain scientist John Yeomans at the University of Toronto in Canada used special microphones to eavesdrop on mice during sex. When they let a male mouse into a female's cage, he approached her with a series of whistle calls and then, during intercourse, sang more complex chirp songs until ejaculation. (Females sing during social reunion with other females but only squeak uncomfortably during sex). Even without sex, the male mice sang complex chirps after the researchers injected them with a low dose of amphetamine, which activates the brain's reward circuitry by boosting levels of the neurotransmitter dopamine. © 2008 American Association for the Advancement of Science.

Keyword: Sexual Behavior; Animal Communication
Link ID: 11497 - Posted: 06.24.2010

Bruce Bower Stimulants have long been prescribed to children diagnosed with attention-deficit hyperactivity disorder, or ADHD. Over the past decade, child psychiatrists have debated the long-term potential for these medications to trigger drug abuse. Two new studies indicate that the stimulants do not increase children's risk of abusing cocaine, nicotine, and other drugs as adults. Although these findings come as a relief to child psychiatrists, not all the news is good. The new investigations, already published online and slated to appear in the May American Journal of Psychiatry, underscore earlier evidence that youngsters with ADHD frequently become drug abusers, whether or not they take prescribed stimulants. "It is still critical that young people with ADHD be screened for substance abuse," says Nora D. Volkow, director of the National Institute on Drug Abuse in Bethesda, Md. Boys with ADHD who start stimulant treatment early, at age 6 or 7, face a lower risk of later drug abuse than do those who begin taking medication later, between ages 8 and 12, report psychologist Salvatore Mannuzza of New York University's Child Study Center and his colleagues. ©2008 Society for Science & the Public

Keyword: ADHD; Drug Abuse
Link ID: 11496 - Posted: 06.24.2010

Inherited variations in the amount of an innate anxiety-reducing molecule help explain why some people can withstand stress better than others, according to a new study led by researchers at the National Institute on Alcohol Abuse and Alcoholism (NIAAA), part of the National Institutes of Health (NIH). "Stress response is an important variable in vulnerability to alcohol dependence and other addictions, as well as other psychiatric disorders," noted NIAAA Director Ting-Kai Li, M.D. "This finding could help us understand individuals' initial vulnerability to these disorders." Scientists led by David Goldman, M. D., chief of the NIAAA Laboratory of Neurogenetics, identified gene variants that affect the expression of a signaling molecule called neuropeptide Y (NPY). Found in brain and many other tissues, NPY regulates diverse functions, including appetite, weight, and emotional responses. "NPY is induced by stress and its release reduces anxiety," said Dr. Goldman. "Previous studies have shown that genetic factors play an important role in mood and anxiety disorders. In this study, we sought to determine if genetic variants of NPY might contribute to the maladaptive stress responses that often underlie these disorders." A report of the findings appears online today in Nature. Analyses of human tissue samples led by researchers at NIAAA identified several NPY gene variants.

Keyword: Stress; Genes & Behavior
Link ID: 11495 - Posted: 04.05.2008

Seth Borenstein -- Scientists say they have pinpointed a genetic link that makes people more likely to get hooked on tobacco, causing them to smoke more cigarettes, making it harder to quit, and leading more often to deadly lung cancer. The discovery by three separate teams of scientists makes the strongest case so far for the biological underpinnings of the addiction of smoking and sheds light on how genetics and cigarettes join forces to cause cancer, experts said. The findings also lay the groundwork for more tailored quit-smoking treatments. "This is kind of a double whammy gene," said Christopher Amos, a professor of epidemiology at the M.D. Anderson Cancer Center in Houston and author of one of the studies. "It makes you more likely to be dependent on smoking and less likely to quit smoking." A smoker who inherits this genetic variation from both parents has an 80 percent greater chance of lung cancer than a smoker without the variants, the researchers reported. And that same smoker on average lights up two extra cigarettes a day and has a much harder time quitting than smokers who don't have these genetic differences. The three studies, funded by governments in the United States and Europe, is being published Thursday in the journals Nature and Nature Genetics. © 2008 Discovery Communications, LLC

Keyword: Drug Abuse; Genes & Behavior
Link ID: 11494 - Posted: 06.24.2010

Ewen Callaway It's thought of as a sexual stereotype: boys tend to play with toy cars and diggers, while girls like dolls. But male monkeys, suggests research, are no different. This could mean that males, whether human or monkey, have a biological predisposition to certain toys, says Kim Wallen, a psychologist at Yerkes National Primate Research Center in Atlanta, Georgia. Wallen's team looked at 11 male and 23 female rhesus monkeys. In general the males preferred to play with wheeled toys, such as dumper trucks, over plush dolls, while female monkeys played with both kinds of toys. This conclusion may upset those psychologists who insist that sex differences – for example the tendency of boys to favour toy soldiers and girls to prefer dolls – depend on social factors, not innate differences. "A five-year-old boy whose compatriots discover has a collection of Barbies is likely to take a lot of flak," Wallen says. Social factors undoubtedly influence children's preferences, he says, but in general boys tend to be pickier with toys than girls. © Copyright Reed Business Information Ltd.

Keyword: Sexual Behavior; Development of the Brain
Link ID: 11493 - Posted: 06.24.2010

Michael Hopkin Could a gene be partly responsible for the behaviour of some of the worlds most infamous dictators? Selfish dictators may owe their behaviour partly to their genes, according to a study that claims to have found a genetic link to ruthlessness. The study might help to explain the money-grabbing tendencies of those with a Machiavellian streak — from national dictators down to 'little Hitlers' found in workplaces the world over. Researchers at the Hebrew University in Jerusalem found a link between a gene called AVPR1a and ruthless behaviour in an economic exercise called the 'Dictator Game'. The exercise allows players to behave selflessly, or like money-grabbing dictators such as former Zaire President Mobutu, who plundered the mineral wealth of his country to become one of the world's richest men while its citizens suffered in poverty. The researchers don't know the mechanism by which the gene influences behaviour. It may mean that for some, the old adage that "it is better to give than to receive" simply isn't true, says team leader Richard Ebstein. The reward centres in those brains may derive less pleasure from altruistic acts, he suggests, perhaps causing them to behave more selfishly. © 2008 Nature Publishing Group

Keyword: Aggression; Genes & Behavior
Link ID: 11492 - Posted: 06.24.2010