By LAWRENCE OSBORNE In a concrete basement at the University of Sydney, I sat in a chair waiting to have my brain altered by an electromagnetic pulse. My forehead was connected, by a series of electrodes, to a machine that looked something like an old-fashioned beauty-salon hair dryer and was sunnily described to me as a ''Danish-made transcranial magnetic stimulator.'' This was not just any old Danish-made transcranial magnetic stimulator, however; this was the Medtronic Mag Pro, and it was being operated by Allan Snyder, one of the world's most remarkable scientists of human cognition. Nonetheless, the anticipation of electricity being beamed into my frontal lobes (and the consent form I had just signed) made me a bit nervous. Snyder found that amusing. ''Oh, relax now!'' he said in the thick local accent he has acquired since moving here from America. ''I've done it on myself a hundred times. This is Australia. Legally, it's far more difficult to damage people in Australia than it is in the United States.'' ''Damage?'' I groaned. ''You're not going to be damaged,'' he said. ''You're going to be enhanced.'' Copyright 2003 The New York Times Company

Keyword: Autism
Link ID: 3948 - Posted: 06.23.2003

Outgoing and timid adults react differently to strangers. CLAIRE TILSTONE US scientists have spotted something different in the brains of shy and outgoing people when they meet a new face1. What's more, it seems that the difference has its roots in childhood. Individuals' approaches to unfamiliarity as kids appear to be echoed by their neural responses to novelty later in life. The distinction may rest in an almond-shaped region of the brain called the amygdala, which is involved in emotion and survival. When Carl Schwartz of Massachusetts General Hospital in Charlestown showed pictures of strangers to young adults, he saw more activity in the amygdala of thirteen 21-year-olds with a history of shyness than he did in adults who've been oozing confidence since kindergarten. "We can see that signature in the brain's circuitry," he says. © Nature News Service / Macmillan Magazines Ltd 2003

Keyword: Emotions
Link ID: 3947 - Posted: 06.24.2010

DNA defect may cause involuntary physical and verbal tics. JOHN WHITFIELD Researchers have found a gene mutation that seems to lead to the mental disorder Tourette's syndrome. The gene is normally switched on in nerve cells; its disruption might make them hyperactive. The gene has been detected in only one family so far. Studies of more people with Tourette's syndrome are needed to confirm its involvement in the condition. "This gene might be involved in some people with Tourette's syndrome, but it won't be in all of them," says the leader of the team that found it, Ben Oostra, of Erasmus University, Rotterdam, the Netherlands. © Nature News Service / Macmillan Magazines Ltd 2003

Keyword: Tourettes
Link ID: 3946 - Posted: 06.24.2010

People with a common breathing disorder which strikes while they are asleep could be at increased risk of getting diabetes later in life. Scientists have found a link between obstructive sleep apnoea and early signs of diabetes. They say it is possible the side-effects of apnoea could be causing permanent damage to their metabolism. Sleep apnoea leads an interruption of breathing during sleep - and affects one in ten middle-aged men. Being obese makes the condition much more likely. Sleep apnoea is potentially damaging because it not only reduces the oxygen concentration in the blood stream, but also disturbs sleep patterns and causes daytime fatigue. (C) BBC

Keyword: Sleep
Link ID: 3945 - Posted: 06.21.2003

Brain fluid holds clues to psychopathic behaviour The levels of two chemicals in the spinal fluid may give doctors extra clues about the presence of psychopathic personality traits. The findings of a Swedish research team may also bring scientists closer to understanding the root cause of these problems. The chemicals involved, known in short as HVA and 5-HIAA, are by-products of the breakdown of two key brain chemicals which send messages around the organ. The levels of these brain chemicals, dopamine and serotonin, have already been linked to mood and personality traits. In the latest study, a group of 28 men, all of whom had committed violent crimes, including murder, assault, and rape, were persuaded to allow a sample of their cerebrospinal fluid - the liquid which bathes the brain and spinal cord - to be taken by doctors. After a standard personality rating system had been used to assess the men, this was compared against what was found in the fluid. (C) BBC

Keyword: Aggression
Link ID: 3944 - Posted: 06.21.2003

Experts are studying the "torrid and tangled" sex life of one of the UK's most popular pet fish as they try to learn how the battle of the sexes influences evolution. Researchers at St Andrews University hope that the guppy's mating behaviour can help them unravel the mystery of how new species are formed. They have put Trinidadian guppies under the microscope because the fish is in the process of splitting into two new species. Two groups that have been living in separate river systems for about two million years were put together and DNA fingerprinting is being used to establish the parentage of baby fish. The research team discovered a web of sexual conflict, interbreeding, sneaky mating behaviour and sperm competition. Professor Anne Magurran said the study had found a number of ways in which "reproductive isolation" was being encouraged. (C) BBC

Keyword: Evolution; Sexual Behavior
Link ID: 3943 - Posted: 06.21.2003

Which is stronger—nature or nurture? The latest science says genes and your experience interact for your whole life By MATT RIDLEY One perennial debate about nature and nurture—which is the more potent shaper of the human essence?—is constantly rekindled. It flared up again in the London Observer of Feb. 11, 2001. revealed: the secret of human behavior, read the banner headline. environment, not genes, key to our acts. The source of the story was Craig Venter, the self-made man of genes who had built a private company to read the full sequence of the human genome in competition with an international consortium funded by taxes and charities. That sequence—a string of 3 billion letters, composed in a four-letter alphabet, containing the complete recipe for building and running a human body—was to be published the very next day (the competition ended in an arranged tie). The first analysis of it had revealed that there were just 30,000 genes in it, not the 100,000 that many had been estimating until a few months before. Details had already been circulated to journalists under embargo. But Venter, by speaking to a reporter at a biotechnology conference in France on Feb. 9, had effectively broken the embargo. Not for the first time in the increasingly bitter rivalry over the genome project, Venter's version of the story would hit the headlines before his rivals'. ?We simply do not have enough genes for this idea of biological determinism to be right,? Venter told the Observer. ?The wonderful diversity of the human species is not hard-wired in our genetic code. Our environments are critical.? In truth, the number of human genes changed nothing. Venter's remarks concealed two whopping nonsequiturs: that fewer genes implied more environmental influences and that 30,000 genes were too few to explain human nature, whereas 100,000 would have been enough. As one scientist put it to me a few weeks later, just 33 genes, each coming in two varieties (on or off), would be enough to make every human being in the world unique. There are more than 10 billion combinations that could come from flipping a coin 33 times, so 30,000 does not seem such a small number after all. Besides, if fewer genes meant more free will, fruit flies would be freer than we are, bacteria freer still and viruses the John Stuart Mill of biology. Copyright © 2003 Time Inc.

Keyword: Genes & Behavior
Link ID: 3942 - Posted: 06.24.2010

By STEVEN LEE MYERS BAGHDAD, Iraq, — It was only after the fighting stopped that Pvt. Christopher L. Labier began to feel the symptoms, though of what he did not know at the time. He became withdrawn. He lost his energy and his appetite. Worst of all were the images that flashed through his mind. They were not nightmares, since to have nightmares you have to go to sleep. And he could not. "I'd be lying there for hours every night," he said. "I would see scenes. I would hear voices. I kept hearing one of the squad leaders tell my team leader to help him ID the bodies of his guys." Their bodies had been torn apart by a bomb packed inside a taxi. The explosion killed four soldiers from the First Brigade of the Army's Third Infantry Division at a checkpoint north of Najaf on March 29. Had Private Labier's platoon not been relieved a few minutes before, it might have been his body out there, rent beyond recognition. Copyright 2003 The New York Times Company

Keyword: Stress
Link ID: 3941 - Posted: 06.24.2010

SHARON BEGLEY, The Wall Street Journal It wasn't the kind of passage you usually encounter in a strait-laced science journal: "I have had to spend periods of several weeks on a remote island in comparative isolation," Anonymous wrote in Nature. Curiously, he continued, the day before he was due for shore leave his beard grew noticeably: "I have come to the conclusion that the stimulus for (this) growth is related to the resumption of sexual activity." Neither Anonymous nor his fellow scientists were surprised that the aforementioned activity would loose a flood of testosterone, which affects beards the way Miracle-Gro affects tomato plants. No, the weird part is that merely anticipating female companionship did the trick. Just as stress in the med students I wrote about last week altered the expression of genes in their immune systems, so libidinous thoughts seem to affect gene expression, says developmental psychologist David Moore of Pitzer College in Claremont, Calif. Thoughts can cause the release of hormones that can bind to DNA, "turning genes `on' or `off.' " ©2003 Associated Press

Keyword: Genes & Behavior; Hormones & Behavior
Link ID: 3940 - Posted: 06.24.2010

SHARON BEGLEY, The Wall Street Journal For a trait so highly heritable, intelligence has been awfully reluctant to give up its genes. There is wide agreement that cognitive ability at least partly reflects the influence of DNA: Dozens of studies of thousands of twins have shown identical twins, who share the same genes, tend to have more-similar IQs than do other sibling pairs, and children match the IQ of their biological more than their adoptive parents. Together, these studies imply genes account for about 50 percent of the difference in intelligence from one person to the next. That's a high enough "heritability" that you'd think genome labs would be practically spitting out genes related to intelligence. ©2003 Associated Press

Keyword: Intelligence; Genes & Behavior
Link ID: 3939 - Posted: 06.24.2010

by Roxanne Patel Who are you? Really. What makes you who you are? Really. Is it God? Nature? Chance or science? Do you know where you come from? You should know. You must know, because these are the most important questions of our time. We are at the dawn of an age when life can be created in a dish, when sex and health and personality can be determined with a syringe--when you can decide, literally for God's sake, to give your child blond hair, the ability to play the flute, a face like yours, or a voice that's exactly like your dead wife's. How far will you go to ensure that your child is disease- and pain-free? Smart? Able to throw a baseball? How far will you go to ensure your child is like you? You need to have an answer. You must decide what it all means for you. And you will have to answer for your decisions--or lack of decisions. "Genes will determine everything." He's only just begun his late-February guest lecture at Princeton, and already University of Pennsylvania bioethicist Glenn McGee has dazzled a room full of undergrads into stunned silence. Just 35 years old, McGee is one of the country's most outspoken young thinkers on reproductive technology, like cloning, gene research and dna modification. And onstage, he is doing what he's best known for: Helping the general public understand the sci-fi world of genomes and clones and stem cells--which, of course, isn't science fiction anymore. Doughy and baby-faced, he paces, shouts, waves his arms. Copyright 2002 Metrocorp

Keyword: Genes & Behavior
Link ID: 3938 - Posted: 06.20.2003

By THE ASSOCIATED PRESS WASHINGTON, (AP) — No one under age 18 should be prescribed the drug Paxil for major depression because it might increase the risk of suicide, the government said today. The Food and Drug Administration has never approved pediatric use of Paxil, sold under the name Seroxat. But some doctors prescribe the adult drug for children anyway. Children and teenagers already taking Paxil should not suddenly stop the pills, the agency emphasized. Some doctors may believe that the drug is helping enough to keep a particular patient on the drug, which the F.D.A. warning does not forbid. Those who do stop taking Paxil need medical supervision to taper off. Copyright 2003 The New York Times Company

Keyword: Depression; Development of the Brain
Link ID: 3937 - Posted: 06.24.2010

By L. L. DESAUTELS Not long ago, I made a decision that up until that time was unthinkable: give up driving a car the traditional way. Multiple sclerosis has numbed my feet to the point where I can no longer tell without looking whether they are on the pedals, and my hip flexors are so weakened that naturally lifting my leg from gas to brake and back again is impossible. For 25 years, driving had always been an enormous pleasure and privilege, and it was now fast becoming riddled with uncertainty, and potentially unsafe. For many of us, driving, like countless other tasks we take for granted, is associated with personal freedom and a sense of control. What a thrill to be on the open road, windows down and your favorite song on the radio! Copyright 2003 The New York Times Company

Keyword: Multiple Sclerosis
Link ID: 3936 - Posted: 06.20.2003

Night owls and early birds owe differences to clock-gene length. MICHAEL HOPKIN Whether you are a morning or an evening person could depend on a single gene, a study of extreme sleeping habits has revealed. Understanding the body clock's genetic basis may help people to make the most of their day. Night owls and early birds tend to carry different versions of a gene called Per3, says Simon Archer of the University of Surrey in Guildford, UK. This difference may make their preferred sleep cycles longer or shorter than 24 hours. The brain uses the cycle of light and dark to align its clock with the Earth's 24-hour cycle. "Every day we reset our clocks slightly," says Archer. People whose natural cycles are much shorter or longer than 24 hours often find themselves wakeful or sleepy at odd times. © Nature News Service / Macmillan Magazines Ltd 2003

Keyword: Sleep; Genes & Behavior
Link ID: 3935 - Posted: 06.24.2010

Blue-throated lizards that help each other achieve reproductive success are also helping scientists understand how social cooperation evolved. SANTA CRUZ, CA--Blue-throated lizards that help each other achieve reproductive success are also helping scientists understand how social cooperation evolved. Most examples of cooperative behavior in animals involve cooperation between genetically related individuals, which is explained by the theory of "kin selection." Now, researchers have described an example of cooperation between genetically similar but unrelated members of a lizard species common in the western United States. Their findings, published in the June 20 issue of the journal Science, shed new light on the evolution of cooperation and social behavior. Barry Sinervo, a professor of ecology and evolutionary biology at the University of California, Santa Cruz, has been studying the side-blotched lizard (Uta stansburiana) since 1989. He recently teamed up with French ecologist Jean Clobert to analyze ten years worth of data from Sinervo's ongoing field studies. The two scientists are coauthors of the new paper in Science.

Keyword: Evolution; Sexual Behavior
Link ID: 3934 - Posted: 06.20.2003

MGH imaging study finds differences in brain area responsible for vigilance A key area in the brains of people who displayed an inhibited temperament as toddlers shows a greater response to new faces than does the same brain area in adults who were uninhibited early in life, according to a study by researchers from Massachusetts General Hospital (MGH). The imaging studies of the amygdala – a part of the brain that responds to events requiring extra vigilance – appear in the June 20 issue of Science. "Our findings both support the theory that differences in temperament are related to differences in amygdala function, something earlier technology could not prove, and show that the footprint of temperamental differences observed when people are younger persist and can be measured when they get older," says Carl Schwartz, MD, director of the developmental psychopathology lab in the MGH Psychiatric Neuroscience Program, the paper's first author. "In a way, this research is the neuroscientist's version of the 'Seven-Up' movies," he adds, referring to a well-known series of British documentaries that have revisited a group of people every seven years for more than 40 years. In psychological terms, temperament refers to a stable emotional and behavioral profile that is observed in infancy and partially controlled by genetic factors. One of the most carefully studied temperamental measures relates to a child's typical response to unfamiliar people, objects and situations. It usually is described with terms such as shyness versus sociability, caution versus boldness, or withdrawal versus approach. The two extremes of this measurement define types of children called inhibited and uninhibited by Jerome Kagan, PhD, professor of Psychology at Harvard University, a co-author of the current study.

Keyword: Emotions
Link ID: 3933 - Posted: 06.24.2010

Are you a lark or an owl? Are you at your best early in the morning or late at night? Whatever the answer, scientists believe they may now know why some of us are early risers while others prefer to burn the midnight oil. The answer appears to lie in our genes. Researchers at the University of Surrey say they have found a link between people's preference for mornings or evenings and a gene called Period 3. This gene is one of those involved in regulating the body's internal clock. It comes in two forms - a shorter and longer one. Researchers have found that people with an extreme preference for early mornings are more likely to have a long version of Period 3. In contrast, those with an extreme preference for evenings are more likely to have the shorter version. (C) BBC

Keyword: Genes & Behavior; Sleep
Link ID: 3932 - Posted: 06.19.2003

Exclusive from New Scientist Print Edition A study of mercury levels in the baby hair of children who were later diagnosed with autism has produced startling results. The babies had far lower levels of mercury in their hair than other infants, leading to speculation that autistic children either do not absorb mercury or, more likely, cannot excrete it. The results will be seized upon by parents who blame vaccines containing the mercury-based preservative thimerosal for their children's autism, some of whom are suing health authorities in the US and Canada. (The MMR vaccine that some accuse of triggering autism, despite a lack of credible evidence, does not contain mercury.) But while the study's findings support the theory that some children have a genetic fault that makes them far more susceptible to mercury poisoning, the results certainly do not prove this, or that thimerosal is involved. © Copyright Reed Business Information Ltd.

Keyword: Autism
Link ID: 3931 - Posted: 06.24.2010

By Danny Kingsley, ABC Science Online — Forget about using those expensive sprays to try and attract the opposite sex — humans don't have the ability to detect pheromones, and American research concludes it is due to our color vision. The research, undertaken by Assistant Professor Jianzhi Zhang from the University of Michigan, involved a comparison of the genes of primates that can see color and those that can't. It seems that males developing color vision negated the need for pheromones to attract mates. Pheromones are water-soluble chemicals released by an individual as a signal to others of the same species. They are used for social and reproductive behavior and in land-based animals they are mainly sensed by an organ called the vomeronasal organ (VNO). But humans and other primates only have remnant VNOs, so they have no or very little ability to detect pheromones. Copyright © 2003 Discovery Communications Inc.

Keyword: Chemical Senses (Smell & Taste)
Link ID: 3930 - Posted: 06.24.2010

-- A protein that plays a role in muscular dystrophies also may be involved in peripheral neuropathy - disorders of the nerves that carry messages between the brain and the rest of the body. The findings, by University of Iowa researchers and colleagues, may shed light on the causes and mechanisms of human peripheral neuropathies, which cause pain, numbness and muscle wasting. Peripheral neuropathies can be acquired as a result of diseases including diabetes and Hansen's disease (leprosy) or can be inherited. Some congenital peripheral neuropathies (those present at birth) can cause limb deformities. The UI study may suggest new treatment strategies for these conditions. In the peripheral nervous system, dystroglycan is found in Schwann cells, which wrap themselves around peripheral axons (nerve fibers) and protect them by producing a myelin sheath. The sheath allows nerve impulses to move faster and more efficiently along the nerves. If nerve fibers are the body's electrical wiring, then the myelin sheath represents the insulation. Copyright © 1992-2003 Bio Online, Inc.

Keyword: Muscles; Glia
Link ID: 3929 - Posted: 06.24.2010