By Rossella Lorenzi, Discovery News — Cell phone exposure stirs the brain, according to an Italian study which investigated the effects of mobile phone emissions on the motor cortex. The study, accepted for publication in the Annals of Neurology, proved that the electromagnetic fields generated by cell phones produce an increase in excitability within the brain's cortex. The cortex is the largest part of the human brain, associated with higher brain function. "We still do not know whether this effect is neutral or potentially dangerous or beneficial to brain functioning," Paolo Maria Rossini, a neurologist with the Fatebenefratelli IRCCS Research Centre of Brescia, told Discovery News. Rossini and colleagues used a technique called paired-pulse transcranial magnetic stimulation to investigate cortical excitability in 15 healthy young male volunteers. Each volunteer was exposed to emissions from phones using the Global System for Mobile Communications, or GSM. The researchers mounted a common GSM phone to the left side of the subject's head by using a modified helmet that assured a constant distance of 15 mm between phone and ear. An identical phone, without battery, was positioned on the right side of the head. © 2006 Discovery Communications Inc.

Keyword: Miscellaneous
Link ID: 8966 - Posted: 06.24.2010

Girls from broken homes may grow up to be less attractive, research published by the Royal Society shows. Two studies from a team at St Andrew's University suggested that women whose parents had separated or had a poor relationship looked more masculine. Researchers assessed facial features and body shape in 229 women and found those from stable homes appeared more feminine and healthy. The results may be linked to levels of testosterone - the male sex hormone. However, it is unclear if increased testosterone in the offspring of parents who separate is genetic or caused by stress of an unhappy family life. Researchers took photographs of psychology students who had completed a questionnaire about their family background. The pictures were rated for attractiveness, feminity, and healthiness. Women whose parents had a good relationship were found to be significantly more attractive than women whose parents had separated. Women whose parents had stayed together but had a poor relationship were rated the least attractive of the three groups and were also judged to be the least healthy. In a second study of 87 of the same young women, researchers assessed body mass index, waist-hip ratio, and waist-chest ratio. Growing up with parents who had a poor relationship was associated with increased weight around the waist, producing a more masculine figure and an increased body mass index. The findings are published in the Proceedings of the Royal Society. (C)BBC

Keyword: Sexual Behavior
Link ID: 8965 - Posted: 05.25.2006

By Rebecca Morelle Mice with the mutant gene have a white-tipped tail and white feet Scientists say they have demonstrated that animals can defy the laws of genetic inheritance. Researchers found that mice can pass on traits to their offspring even if the gene behind those traits is absent. The scientists suggest RNA, a chemical cousin of DNA, passes on the characteristic - in this experiment, a spotty tail - to later generations. But more work may be needed to confirm the conclusions of the study, which appears in the journal Nature. The research focuses on a gene called Kit, which comes in two varieties: "normal" and "mutant". The mice inherit two Kit genes, one from each parent; a mutant version gives them a spotty tail. According to Mendel's laws of genetic inheritance, the combination of normal and mutant Kit genes inherited by the mice should alone determine whether the mouse has a spotted or unspotted tail. The scientists, based at the French Institute of Health and Medical Research (Inserm) and the University of Nice-Sophia Antipolis, used mice which carry one normal version of Kit and one mutant version, giving them spotted tails. They bred these mice together, producing offspring with a range of Kit gene combinations: two mutant genes (these are shown to die shortly after birth) one mutant and one normal gene (these should be "spotty" like their parents) two normal genes (these should not be spotty). However, the researchers found that mice born with two normal versions of Kit also had a spotted appendage. "We were very surprised to see this," said Professor Minoo Rassoulzadegan, a geneticist at the University of Nice and lead author on the paper. (C)BBC

Keyword: Genes & Behavior
Link ID: 8964 - Posted: 05.25.2006

A Queensland Brain Institute-led team has identified a molecule that plays a key role in establishing the major nerve connections between each side of the adult brain. QBI neural migration laboratory head Associate Professor Helen Cooper said her group's research provided new clues regarding development of the corpus callosum, the main connecting nerve tract that shuttles information between the left and right hemispheres of the adult brain. Using a mouse model, neuroscientists at The University of Queensland – working with Associate Professor Steven Stacker and his team at the Ludwig Institute for Cancer Research in Melbourne – have identified a molecule that helps control development of the corpus callosum. The corpus callosum has millions of individual nerve fibres. If these fibres fail to reach their correct targets in the opposite hemisphere, people can suffer from epilepsy, and experience some degree of mental retardation. "Our study is the first to identify a growth molecule that guides young nerves away from the corpus callosum and towards their targets in the opposite hemisphere," Dr Cooper said. "We have shown that the Ryk receptor molecule facilitates the targeting of individual nerve fibres.

Keyword: Development of the Brain; Laterality
Link ID: 8963 - Posted: 06.24.2010

LA JOLLA, CA - It doesn't take John Wayne's deliberate, pigeon-toed swagger or Marilyn Monroe's famously wiggly sway to judge a person's gender based on the way they move. People are astonishingly accurate when asked to judge the gender of walking human figures, even when they are represented by 15 small dots of light attached to major joints of the body. And not only that, when human observers watched the walking motion of a male so-called "point light walker," they were more sensitive to the female attributes when watching the next figure in the sequence. This suggests that the human brain relies on specialized neurons that tell gender based on gait, report researchers at the Salk Institute for Biological Studies in the May 21 advance online edition of Nature Neuroscience. "Our judgment of gender can adapt within seconds," says senior author Gene Stoner, a neuroscientist in the Vision Center Laboratory at the Salk Institute. "The gaits of males and females may vary geographically or culturally and this mechanism allows us to adapt very quickly to local ways of walking," he adds. How humans move reflects, in part, gender-specific differences in shape such hip-to-waist ratio and the like. Such inherent differences in gait might then be exaggerated by an individual to emphasize their gender. "Our new data suggests that there are neurons selective for gender based on these motion cues and that they adjust their selectivity on the fly," Stoner explains.

Keyword: Sexual Behavior
Link ID: 8962 - Posted: 05.25.2006

by John R. Searle Review by Maria Antonietta Perna Granted, as an introductory text Mind: A Brief Introduction might be said to be particularly brief. However, if Searle keeps his introduction brief, this is because the present book does much more than introducing the reader to a fascinating philosophical subject in clear and accessible language. What Searle aims to do is far more ambitious: along the lines of his previous publications on the philosophy of mind, especially those dealing with consciousness and language, he argues for a radical break with the entire post-Cartesian tradition and its conceptual framework in which the entire discipline is steeped. In fact, it is the main thesis of the book as stated in the Preface that the philosophy of mind is unique among contemporary philosophical subjects, in that all of the most famous and influential theories are false (p.1). By 'theories' Searle means all kinds of dualist positions as well as the various existing materialist approaches. However, in the midst of false assumptions and consequent misguided views with which this branch of philosophy is allegedly bedevilled, there lie core elements of truth, and Searle's self-appointed task here is to bring them to the reader's attention and show how they can be fitted into a coherent account of the mind and its relation with the world. The title of the first chapter is telling: 'A Dozen Problems in the Philosophy of Mind'. Searle points out that, in contrast with most philosophical subjects, the general stance of most professionals in the philosophy of mind differs from that upheld by the majority of the educated general public. Most people believe in some sort of dualism according to which human beings are endowed with a mind or soul and a body, whereas contemporary professionals in the field do accept some version of materialism, thus doing away with any notion of an immaterial soul. Most of the twelve problems presented in this chapter, Searle explains, are mostly part of Descartes' legacy to philosophy. © 2006 Maria Antonietta Perna.

Keyword: Miscellaneous
Link ID: 8961 - Posted: 06.24.2010

Although deficits in measures of intelligence are well documented among children exposed to high amounts of alcohol during pregnancy, deficits among children prenatally exposed to low-to-moderate amounts of alcohol are much less understood. A study in the June issue of Alcoholism: Clinical & Experimental Research has found that even light to moderate drinking – especially during the second trimester – is associated with lower IQs in offspring at 10 years of age. "The impact of heavy prenatal alcohol exposure on IQ ranges from a two- to a seven-point decrease," said Jennifer A. Willford, assistant professor of psychiatry at the University of Pittsburgh School of Medicine and lead author of the study. "IQ is a measure of the child's ability to learn and to survive in his or her environment. It predicts the potential for success in school and in everyday life. Although a small but significant percentage of children are diagnosed with Fetal Alcohol Syndrome (FAS) each year, many more children are exposed to alcohol during pregnancy who do not meet criteria for FAS yet experience deficits in growth and cognitive function." "Intellectual functioning is a good first measure of the potential damaging effects of prenatal alcohol exposure," added Paul D. Connor, clinical director of the Fetal Alcohol and Drug Unit and assistant professor in the department of psychiatry and behavioral sciences at the University of Washington. "However, mental retardation only characterizes a minority of patients with FAS and Alcohol-Related Neurodevelopmental Disorder (ARND). There are a number of domains of cognitive functioning that can be impaired even in the face of a relatively normal IQ, including academic achievement (especially arithmetic), adaptive functioning, and executive functions (the ability to problem solve and learn from experiences).

Keyword: Drug Abuse; Development of the Brain
Link ID: 8960 - Posted: 06.24.2010

By Jennifer Viegas, Discovery News — Human ears can wiggle and make noise, and now researchers have a better understanding of how these unusual processes work. Since ear wiggling involves complex coordination of facial muscles, the research could shed light on related disorders, such as Bell’s palsy, which can cause facial paralysis. The ear sounds research, meanwhile, is surprisingly illuminating when it comes to gender and sexuality issues. This is because heterosexual men and women and homosexual women appear to produce different levels of ear noise. While most human ears produce sound, controlled, detectable ear wiggling is not as common. "The mechanism behind ear movements is sophisticated," said Bastiaan ter Meulen, who led the ear wiggling study. Ter Meulen, a researcher at Erasmus MC, a university medical center in Rotterdam, the Netherlands, added that, unlike other facial muscles, ear muscles have their own accessory nucleus -- a control area for muscle function -- in the brainstem. Copyright © 2006 Discovery Communications Inc.

Keyword: Hearing; Sexual Behavior
Link ID: 8959 - Posted: 06.24.2010

A good night's sleep may not just leave you feeling refreshed - it may also help to you keep trim. Researchers from Ohio's Case Western Reserve University, followed nearly 70,000 women for 16 years. They found women who slept five or fewer hours a night were a third more likely to put on at least 33lbs (15kg) than sound sleepers during that time. Details were presented to the American Thoracic Society International Conference in San Diego. The study is by far the largest to track the effects of sleep habits on weight gain over a long period of time. It also found that lighter sleepers were 15% more likely to become obese compared with women who slept for seven hours a night. Obesity is defined as having a Body Mass Index (BMI) of 30 or more. BMI is calculated by dividing weight in kilograms by the square of height in metres. The researchers found that their findings had nothing to do with light sleepers eating too much, or taking too little exercise. On average, women who slept five hours or less per night weighed 5.4 pounds more at the beginning of the study than those sleeping seven hours, and gained an additional 1.6 pounds more over the next 10 years. Lead researcher Dr Sanjay Patel said: "That may not sound like much, but it is an average amount - some women gained much more than that, and even a small difference in weight can increase a person's risk of health problems such as diabetes and hypertension (blood pressure)." (C)BBC

Keyword: Sleep; Obesity
Link ID: 8958 - Posted: 05.24.2006

Since the dawn of time we have sought short-cuts to happiness. Early man got high on psychotropic drugs. Alcohol has been around since the stone age. The designer drugs of today promise ecstasy in a pill. Now neuroscientists are beginning to manipulate happiness in the brain. In a series of experiments in the 1950s and 1960s psychologists pinpointed the pleasure zones in the brains of rats and eventually in human patients. In 1954 Peter Milner and James Olds performed a radical experiment on rats. They implanted electrodes into rats' brains, and found that when they gave electrical brain stimulation the rats seemed to experience pleasure and almost ecstasy at times. The rats could press a lever which would deliver a small current deep into its brain. It was found that they would perform complex and difficult tasks for another dose of stimulation, and would even press the lever up to 2,000 times an hour to the exclusion of eating or drinking. Olds and Milner concluded that they had discovered the area of the brain responsible for reward. In the 1960s, psychiatrist Robert Heath of Tulane University in New Orleans chose to use this same deep brain stimulation on humans. He performed a series of experiments where he put electrodes deep into his patients' brains. Bob Heath hoped to cure depression, pain, and addiction. But controversially he also experimented on gay men. When a mild shock was administered to patients they felt good. When they were handed the controls they chose to press repeatedly - sometimes over a thousand times. But the pleasure stopped when the current was stopped and Heath eventually abandoned his work. In the last few years interest in deep brain stimulation has been taken up by mainstream medicine to help patients with Parkinson's Disease and also to tackle acute pain. (C)BBC

Keyword: Emotions; Drug Abuse
Link ID: 8957 - Posted: 05.24.2006

By DENISE GRADY A poet and artist has enlisted the help of scientists and engineering students to create a "seeing machine" that may eventually help people like her, with severely impaired vision, to read, look at pictures and explore landscapes and buildings. Elizabeth Goldring's eyesight has come and gone over the years. Mostly, it has gone. Now 61, she has had juvenile diabetes since college, and the disease has pecked away at her vision, causing hemorrhages in her retinas, the fragile layer of light-sensitive cells at the back of the eye. About 10 years ago, when she was nearly blind in both eyes, her doctor recommended a test to find out whether she had any healthy retina left at all. The test involved a large $100,000 machine called a scanning laser ophthalmoscope, which would let the doctor examine her retinas and project images directly onto them. If there were any live spots, the device might let her see. It worked. She saw a stick-figure turtle. Ms. Goldring, a poet who has had three books published, asked to see a word. She was able to read "sun." It was the first word she had seen in many months. "For a poet, that's an incredible feeling," she said. "I said almost immediately, 'I need to get in touch with the man who invented this machine.' " Copyright 2006 The New York Times Company

Keyword: Vision
Link ID: 8956 - Posted: 05.24.2006

Michael Hopkin Clinical researchers have discovered that they can rouse semi-comatose patients by giving them, bizarrely, a common sleeping drug. If more wide-ranging tests are successful, the drug could become the first effective treatment for 'persistent vegetative state', the condition at the centre of the US legal battle over sufferer Terri Schiavo last year. British and South African doctors have reported the cases of three semi-comatose patients who were revived for several hours at a time by zolpidem, marketed to millions of insomniacs under the brand name Ambien. The drug allows the semi-comatose patients to talk with friends and family for several hours before the effect wears off, they report in the journal NeuroRehabilitation1. The patients, two of whom suffered severe head injuries in motor accidents and a third who was left brain damaged by a near-drowning incident, have been taking the pills every day for several years, with no severe side effects. "The effect is amazing to say the least," says Ralf Clauss of the Royal Surrey County Hospital in Guildford, UK, who discovered it along with his colleague Wally Nel of the Family Practice in Pollack Park, Springs, South Africa. "They can interact, make jokes and speak on the phone." One of them even mastered catching a baseball. ©2006 Nature Publishing Group

Keyword: Sleep
Link ID: 8955 - Posted: 06.24.2010

Roxanne Khamsi Gene therapy may one day prevent a hereditary form of childhood blindness, researchers say, following a promising study on chickens with the condition. They say the approach, which delayed the onset of blindness in chickens, might one day protect children from becoming blind as the result of an inherited disease called Leber congenital amaurosis (LCA). Chickens with the disease are normally born blind. But six out of seven of the chickens which underwent the gene therapy technique while still in the egg hatched out with sight, says Susan Semple-Rowland at the University of Florida in Gainesville, Florida, US, who led the study. She and her colleagues focused on mutations in the GUCY2D gene, which is responsible for LCA1 – the most common type of LCA, accounting for up to 20% of cases. In people who carry two faulty GUCY2D genes, the cells at the back of the eye are unable to respond properly to light, and therefore cannot send proper visual signals to the brain. Individuals who suffer from this disorder typically become blind in infancy. Semple-Rowland says that the best animal model for LCA1 is found in chickens bred from others that had naturally acquired mutations in their GUCY2D genes. These chickens are born blind, she says. © Copyright Reed Business Information Ltd.

Keyword: Vision; Genes & Behavior
Link ID: 8954 - Posted: 06.24.2010

Problems with walking and balance may be the first sign of Alzheimer's disease, say US researchers. A study of 2,288 elderly people found that such physical symptoms were associated with an increased risk of developing dementia. Researchers from the University of Washington said they believed that exercise could help to stall the progression of the disease. Their study appears in Archives of Internal Medicine. Previous research has suggested that exercise may reduce the risk of Alzheimer's - possibly by boosting blood flow to the brain. Researchers monitored patients every two years for signs of physical and mental decline. At the start of the study, none of the participants had any sign of dementia but after six years 319 individuals had developed dementia - 221 of them had Alzheimer's disease. Those with good physical performance scores at the start of the investigation were three times less likely to develop dementia than those with poor scores. The researchers assessed physical function using a variety of tests. The first indicators of future dementia appeared to be problems with walking and balance. A weak hand grip was a later sign. Study leader Dr Eric Larson said: "We were surprised to find that physical changes can precede declines in thinking. (C)BBC

Keyword: Alzheimers
Link ID: 8953 - Posted: 05.23.2006

By BENEDICT CAREY The patient, Keith, was a deeply religious young man, disabled by paranoia, who had secluded himself for weeks in one of the hospital's isolation rooms. In daily therapy sessions he said little but was always civil, seemingly pleased to have company and grateful for a cigarette and a light. Until one spring morning, when he wrestled the lighter from his therapist's hand and held it to his own head — igniting his hair. "I grabbed him and was slapping at the flames, and he immediately became passive," said Dr. Thomas H. McGlashan, the man's therapist. "He went limp and pulled a blanket over his head." He added, "That patient, that experience, changed everything for me." In a career that has spanned four decades, Dr. McGlashan, now 64 and a professor of psychiatry at Yale, has with grim delight extinguished some of psychiatry's grandest notions, none more ruthlessly than his own. He strived for years to master psychoanalysis, only to reject it outright after demonstrating, in a landmark 1984 study, that the treatment did not help much at all in people, like Keith, with schizophrenia. Once placed on antipsychotic medication, Keith became less paranoid and more expressive. Without it, he quickly deteriorated. Copyright 2006 The New York Times Company

Keyword: Schizophrenia
Link ID: 8952 - Posted: 06.24.2010

By NICHOLAS WADE Researchers taping calls of the putty-nosed monkey in the forests of Nigeria may have come a small step closer to understanding the origins of human language. The researchers have heard the monkeys string two alarm calls into a combined sound with a different meaning, as if forming a word, Kate Arnold and Klaus Zuberbühler report in the current issue of Nature. Monkeys are known to have specific alarm calls for different predators. Vervet monkeys have one call for eagles, another for snakes and a third for leopards. But this seems a far cry from language because the vervets do not combine the calls into anything resembling words or sentences. The putty-nosed monkeys have a "pyow" call meaning there are leopards about and a hacklike sound to warn of the crowned eagle. The "pyow" calls attention to a leopard on the ground. When hearing the "hack" sound, a monkey tends to freeze because movement would betray its position to an eagle. Dr. Arnold and Dr. Zuberbühler, zoologists at the University of St. Andrews in Scotland, noticed that adult male monkeys in each troupe were combining the "pyow" and "hack" calls. Copyright 2006 The New York Times Company

Keyword: Language; Evolution
Link ID: 8951 - Posted: 05.23.2006

Brain damage occasionally leaps to mind to explain the one-sided treatment that political junkies of all stripes dispense, doling out forgiveness for their idols and contempt for their opponents. But a perfectly-normal part of the brain may play a role in the current "Talk Radio" era of polarized politics, suggests a new study. Imagining how other people will think and act in a given situation is a fairly important skill to have in partaking of a civilization, much less in determining whether someone else is about to run a red light. "This is an important question," says Harvard psychologist Jason Mitchell, who headed the new study. In recent years, neurologists have zeroed in on a region of the brain called the prefrontal cortex as key in the making of judgments about other people, Mitchell and his team report in the study, published in the journal Neuron. To test how this brain region works with politics, the study team asked 15 university students from the Boston area to eyeball two faces, drawn at random from a dating website. The students were informed, again at random, that one of the faces belonged to a person "having liberal sociopolitical views and participating in activities typical of many students at Northeast liberal arts colleges" and the other to a "fundamentalist Christian with conservative political and social views who participated avidly in a variety of events sponsored by religious and Republican organizations at a Midwest university," according to the study. Then they asked the students to judge the two people's likes, dislikes and opinions, as well as their own, in a 66-question survey. The catch was they had to answer the questions inside a Magnetic Resonance Imaging machine that would capture images of their brain at work. The questions ranged from whether the people like to drive home for Thanksgiving, to whether they enjoy foreign films or drive a small car for environmental reasons. The students had three seconds to answer each question. Copyright 2006 USA TODAY

Keyword: Brain imaging; Attention
Link ID: 8950 - Posted: 05.23.2006

ST. PAUL, Minn. – Eighteen years later, people who worked with lead have significant loss of brain cells and damage to brain tissue, according to a new study published in the May 23, 2006, issue of Neurology, the scientific journal of the American Academy of Neurology. The study examined 532 former employees of a chemical manufacturing plant who had not been exposed to lead for an average of 18 years. The workers had worked at the plant for an average of more than eight years. The researchers measured the amount of lead accumulated in the workers' bones and used MRI scans to measure the workers' brain volumes and to look for white matter lesions, or small areas of damage in the brain tissue. The higher the workers' lead levels were, the more likely they were to have smaller brain volumes and greater amounts of brain damage. A total of 36 percent of the participants had white matter lesions. Those with the highest levels of lead were more than twice as likely to have brain damage as those with the lowest lead levels. Those with the highest levels of lead had brain volumes 1.1 percent smaller than those with the lowest lead levels. "The effect of the lead exposure was equivalent to what would be expected for five years of aging,"said study author Walter F. Stewart, PhD.

Keyword: Neurotoxins
Link ID: 8949 - Posted: 06.24.2010

PORTLAND, Ore. – Research conducted at Oregon Health & Science University suggests that contrary to popular belief, the body has more than one "body clock." The previously known master body clock resides in a part of the brain called the suprachiasmatic nucleus (SCN). Researchers at OHSU's Oregon National Primate Research Center (ONPRC) have now revealed the existence of a secondary clock-like mechanism associated with the adrenal gland. The research also suggests a high likelihood that additional clocks exist in the body. The study results are printed in the current edition of the journal Molecular Endocrinology. "We're all familiar with the idea that the body has a master clock that controls sleep-wake cycles. In fact, most of us have witnessed the impacts of this clock in the form of jet lag where it takes the body a number of days to adjust to a new time schedule following a long flight," explained Henryk Urbanski, Ph.D., senior author of the study and a senior scientist at ONPRC. "Our latest research suggests that a separate but likely related clock resides in the adrenal gland. The adrenal gland is involved in several important body functions, such as body temperature regulation, metabolism, mood, stress response and reproduction. The research also suggests that other peripheral clocks reside throughout the body and that these clocks are perhaps interconnected." To conduct the research, scientists studied adrenal gland function in rhesus macaque monkeys which is very similar to human adrenal gland function. Specifically, researchers measured gene expression in the adrenal gland of monkeys during a 24-hour period (six times a day, four-hour intervals).

Keyword: Biological Rhythms
Link ID: 8948 - Posted: 06.24.2010

By Jennifer Viegas, Discovery News — Testosterone may be known as the "male hormone," but researchers have discovered that female rock hyraxes have significantly higher levels of the chemical than their male counterparts. It is the first time an adult female mammal has been found to possess testosterone levels consistently equal to, or higher than, those found in males of the same species. Since female members of the furry, badger-like species often outrank males, the find suggests hormone levels may help determine who's the boss, and who is not. "Testosterone probably contributes to females’ aggression and social rank, along with other androgens as well," said Lee Koren, lead author of the study, which was recently published in the journal Hormones and Behavior. Koren, a researcher in the Zoology Department at Tel Aviv University, Israel, added, "High hormonal levels may also contribute to females’ lack of choosiness in the mating season. Finally, testosterone also acts as a stress hormone." "It is possible that females -- with their roles as mothers, sisters and group leaders -- are, understandably, very stressed," she said. Copyright © 2006 Discovery Communications Inc.

Keyword: Aggression; Sexual Behavior
Link ID: 8947 - Posted: 06.24.2010