A woman's voice becomes more alluring when she is at her most fertile, according to US research. Recordings of women taken at different points in their menstrual cycle were played to people of both sexes. New Scientist magazine reports that the voices rated as most attractive belonged to women at peak fertility. The study suggests sex hormones can alter the workings of the voice box, but the change may be too subtle to pick up in many situations. Human reproduction differs from reproduction in other mammals in that there are no obvious signs that a woman is at her fertile phase. However, scientists have suggested that very subtle changes caused by the rise and fall of different sex hormones can be detected by men, who then perhaps find a woman more attractive without necessarily even realising why. The latest research, from the State University of New York at Albany and originally published in the journal Human Evolution and Behavior, involved taking recordings of women counting from one to 10 at four points during the menstrual cycle and then played them back to male and female students. The missing link here is finding out how this works in plain conversation - in a bar, for example. (C)BBC

Keyword: Sexual Behavior; Language
Link ID: 11578 - Posted: 05.01.2008

Administering a hormone contained in contraceptive pills can treat brain injuries, suggests new research out of two Chinese universities. Researchers at Hangzhou Normal University and Zhejiang University have found that giving the hormone progesterone to people with severe brain injuries seems to improve their cognitive function. Previous studies have shown that progesterone can reduce inflammation and have a protective effect on the brain when injured. The Chinese researchers studied 159 patients with acute brain injury, half of whom were given progesterone and the other half placebo for five days following their injury. Patients were classified as having favourable outcomes (good recovery or moderate disability), or unfavourable outcomes (severe disability, vegetative state or death). The randomized double-blind trial revealed that significantly more patients who received progesterone had favourable outcomes at three and six-month intervals than those who received placebo. Forty-seven per cent of the patients who received progesterone and 31 per cent of the placebo group had favourable outcomes and 53 per cent of the progesterone and 70 per cent of the placebo patients had unfavourable outcomes. Copyright © CBC 2008

Keyword: Brain Injury/Concussion; Hormones & Behavior
Link ID: 11577 - Posted: 06.24.2010

By Jasmin Aline Persch Female canaries adore a good old-fashioned love song that abides by rigid musical rules. Mature males always follow the rules. Curiously, young males will go against convention — and rock out to tunes that would not impress the ladies. But the feathery punks will shape up when it counts. In a study by scientists at Rockefeller University in New York City, young male canaries isolated in soundproof cages learned to imitate computer-generated compositions in the first half of their youth. Come spring mating season, they changed their tune to the good old-fashioned canary love song — even though they’d never heard it before. The Rockefeller University researchers were surprised the young male canaries broke steadfast tradition. But the quick turnaround to the conventional emphasizes how crucial the recognizeable canary love song is to coupling. It encourages females to build nests, produce eggs and find a soul mate. Scientists continue to decipher birdsong. They're also studying the musical talents of apes, humpback whales, bats and mice. Listen (above) and learn (below) about these up-and-coming mammal musicians. © 2008 MSNBC Interactive

Keyword: Sexual Behavior; Animal Communication
Link ID: 11576 - Posted: 06.24.2010

Catherine Brahic It has been debated for nearly four decades but no one has yet been able to prove it is chemically possible. Now good evidence suggests that birds can actually "see" the lines of the Earth's magnetic field. Klaus Schulten of the University of Illinois, proposed forty years ago that some animals – including migratory birds – must have molecules in their eyes or brains which respond to magnetism. The problem has been that no one has been able to find a chemical sensitive enough to be influenced by Earth's weak geomagnetic field. Now Peter Hore and colleagues at the University of Oxford have found one. Cryptochromes are a class of light-sensitive proteins found in plants and animals, and are thought to play a role in the circadian clock, in regulating plant growth, and timing coral sex. A few years ago, Henrik Mouritsen of the University of Oldenburg in Germany showed that they were present in the retinal neurons of migratory garden warblers, and that these cells were active at dusk, when the warblers were performing magnetic orientation. Cryptochromes have not yet been made in the lab and obtaining them is difficult, but Hore's team has now shown that a related molecule – a carotenoid-porphyrin-fullerene triad – with similar chemical properties to cryptochromes is sensitive to weak magnetism. © Copyright Reed Business Information Ltd.

Keyword: Vision; Animal Migration
Link ID: 11575 - Posted: 06.24.2010

By CRAIG S. SMITH PARIS — Albert Hofmann, the mystical Swiss chemist who gave the world LSD, the most powerful psychotropic substance known, died Tuesday at his hilltop home near Basel, Switzerland. He was 102. The cause was a heart attack, said Rick Doblin, founder and president of the Multidisciplinary Association for Psychedelic Studies, a California-based group that in 2005 republished Dr. Hofmann’s 1979 book “LSD: My Problem Child.” Dr. Hofmann first synthesized the compound lysergic acid diethylamide in 1938 but did not discover its psychopharmacological effects until five years later, when he accidentally ingested the substance that became known to the 1960s counterculture as acid. He then took LSD hundreds of times, but regarded it as a powerful and potentially dangerous psychotropic drug that demanded respect. More important to him than the pleasures of the psychedelic experience was the drug’s value as a revelatory aid for contemplating and understanding what he saw as humanity’s oneness with nature. That perception, of union, which came to Dr. Hofmann as almost a religious epiphany while still a child, directed much of his personal and professional life. Copyright 2008 The New York Times Company

Keyword: Drug Abuse
Link ID: 11574 - Posted: 06.24.2010

By Charles Q. Choi An analysis of century-old bottles of absinthe — the kind once quaffed by the likes of van Gogh and Picasso to enhance their creativity — may end the controversy over what ingredient caused the green liqueur's supposed mind-altering effects. The culprit seems plain and simple: The century-old absinthe contained about 70 percent alcohol, giving it a 140-proof kick. In comparison, most gins, vodkas and whiskeys are just 80- to 100-proof. In recent years, the psychedelic nature of absinthe has been hotly debated. Absinthe was notorious among 19th-century and early 20th-century bohemian artists as "the Green Fairy" that expanded the mind. After it became infamous for madness and toxic side effects among drinkers, it was widely banned. The modern scientific consensus is that absinthe's reputation could simply be traced back to alcoholism, or perhaps toxic compounds that leaked in during faulty distillation. Still, others have pointed at a chemical named thujone in wormwood, one of the herbs used to prepare absinthe and the one that gives the drink its green color. Thujone was blamed for "absinthe madness" and "absinthism," a collection of symptoms including hallucinations, facial tics, numbness and dementia. © 2008 LiveScience.com.

Keyword: Drug Abuse
Link ID: 11573 - Posted: 06.24.2010

Colin Barras Here's a possible explanation for why rock star Ozzy Osbourne infamously bit the head off a bat: he couldn't stand the competition. Bat calls, it turns out, can reach up to a deafening 140 dB – that's 20 dB louder than a rock concert and 15 dB above the human pain threshold. Bats use high-pitched calls to echolocate because only at those ultrasonic frequencies can they detect their small, swiftly moving insect prey. But high-frequency calls don't travel far through the air, leaving bats unable to detect prey beyond a few metres. Annemarie Surlykke at the University of Southern Denmark in Odense and Elisabeth Kalko of the University of Ulm, Germany, reasoned that bats with the highest frequency calls would compensate for the small detection distance with louder cries, because a louder call travels further. To test this they recorded the calls of 11 bat species living on Barro Colorado Island in Panama. They found that the call of one species – the lesser bulldog bat (Noctilio albiventris) – reached an ear-shattering 137 dB, an estimate they think is likely to be on the conservative side because of the high directionality of the calls. Even so, N. albiventris now holds the record as the loudest winged animal yet recorded. © Copyright Reed Business Information Ltd.

Keyword: Hearing
Link ID: 11572 - Posted: 06.24.2010

By NICHOLAS BAKALAR A new study has found that it may be possible to train people to be more intelligent, increasing the brainpower they had at birth. Until now, it had been widely assumed that the kind of mental ability that allows us to solve new problems without having any relevant previous experience — what psychologists call fluid intelligence — is innate and cannot be taught (though people can raise their grades on tests of it by practicing). But in the new study, researchers describe a method for improving this skill, along with experiments to prove it works. The key, researchers found, was carefully structured training in working memory — the kind that allows memorization of a telephone number just long enough to dial it. This type of memory is closely related to fluid intelligence, according to background information in the article, and appears to rely on the same brain circuitry. So the researchers reasoned that improving it might lead to improvements in fluid intelligence. First they measured the fluid intelligence of four groups of volunteers using standard tests. Then they trained each in a complicated memory task, an elaborate variation on Concentration, the child’s card game, in which they memorized simultaneously presented auditory and visual stimuli that they had to recall later. Copyright 2008 The New York Times Company

Keyword: Learning & Memory
Link ID: 11571 - Posted: 06.24.2010

By Nikhil Swaminathan It is well established that the brain uses more energy than any other human organ, accounting for up to 20 percent of the body's total haul. Until now, most scientists believed that it used the bulk of that energy to fuel electrical impulses that neurons employ to communicate with one another. Turns out, though, that is only part of the story. A new study in Proceedings of the National Academy of Sciences USA indicates that two thirds of the brain's energy budget is used to help neurons or nerve cells "fire'' or send signals. The remaining third, however, is used for what study co-author Wei Chen, a radiologist at the University of Minnesota Medical School, refers to as "housekeeping," or cell-health maintenance. Researchers reached their conclusions after imaging the brain with magnetic resonance spectroscopy (MRS) to measure its energy production during activity shifts. Chen says the technology, which has been around for three decades and is used to track the products of metabolism in different tissues, could prove instrumental one day in detecting brain defects or to diagnose tumors or precursors of neurodegenerative diseases (such as Alzheimer's and Parkinson's) early. © 1996-2008 Scientific American Inc.

Keyword: Brain imaging
Link ID: 11570 - Posted: 06.24.2010

Nick Bryant Australian scientists believe they may have discovered how to help people lose weight without cutting back on food. Researchers in Melbourne found that by manipulating fat cells in mice they were able to speed up metabolism. After removing a particular enzyme, scientists found the mice were able to eat the same amount as others but burn more calories and gain less weight. The breakthrough could pave the way for fat-burning drugs and also help to combat diabetes. The research found that mice in which the angiotensin converting enzyme (ACE) had been removed were, on average, 20% lighter than normal mice and had up to 60% less body fat. Because of their faster metabolisms, it also appeared they had less chance of developing diabetes because they processed sugar more quickly. Drugs which impair the action of ACE in humans already exist, and are used to combat high blood pressure. The latest research could help the development of weight loss pills. The question is whether they will have the same slimming effect on people as they have done on mice. Dr Ian Campbell, medical director of the charity Weight Concern, said the study was "interesting", but stressed the work had only been carried out in mice. (C)BBC

Keyword: Obesity
Link ID: 11569 - Posted: 04.29.2008

By ABIGAIL ZUGER, M.D. Marya Hornbacher is a virtuoso writer: humorous, articulate and self-aware. She is also, as she has now documented in two books, incurably mentally ill. Even on the best possible treatment, Ms. Hornbacher tiptoes along the same high wire as Plath, Lowell, Woolf and the rest of the unbalanced artistes. Off medication, she reliably falls into a turmoil of confused self-destruction, which, as she would be the first to acknowledge, means heartbreak and worry for her friends and relatives, challenges for her doctors, and, in the age-old contradiction, new fodder for her muse. For scientists trying to parse the mystery of brain and mind, she is one more case of the possible link between mental illness and artistic creativity. With all our scans and neurotransmitters, we are not much closer to figuring out that relationship than was Lord Byron, who announced that poets are “all crazy” and left it at that. But effective drugs make the question more urgent now: would Virginia Woolf, medicated, have survived to write her final masterpiece, or would she have spent her extra years happily shopping? Copyright 2008 The New York Times Company

Keyword: Anorexia & Bulimia; Schizophrenia
Link ID: 11568 - Posted: 06.24.2010

By Dennis Drabelle I never used to be a napper. In fact, daytime slumber was virtually beyond a congenitally wired type like me. My buddies would catch 40 winks on the long bus ride home from our high school, but for me that was out of the question. With age, however, my metabolism has changed. After the double whammy of a late-morning run and lunch, I'm pretty much a goner. I lie down and nod off in much the same way that Marlene Dietrich fell in love in that old song of hers: because I can't help it. While it lasted, though, my nap resistance put me in sync with the American way of sleep: Do it all at once and strictly at night. Traditionally, we've begrudged ourselves naps. They may be forced on toddlers, recommended for pregnant women and tolerated among senior citizens with nothing better to do, but they've been frowned upon for worker bees in their prime. Recently, however, sleep scientists have discovered advantages to napping, which they view not just as solace but also as something akin to brain food. No longer written off as a cop-out for the weak and the bored, the nap is coming into its own as an element of a healthy life. When you take a look at American history, we might seem to be a nap-friendly people. After all, some of our most productive figures napped shamelessly during the day, among them Benjamin Franklin and Thomas Edison. But they probably did so because, like Dietrich, they couldn't help it. Consider the daily schedule Franklin drew up for "The Art of Virtue," a treatise he worked on for 50 years but never finished: Over a 24-hour period, sleep gets allotted a mere five hours. Or take the contemptuous words of Edison: "Sleep is an acquired habit. Cells don't sleep. Fish swim in the water all night. Even a horse doesn't sleep. A man doesn't need any sleep." © Copyright 1996-2008 The Washington Post Company

Keyword: Sleep
Link ID: 11567 - Posted: 06.24.2010

Heidi Ledford Can training one aspect of the mind, such as memory, improve overall mental sharpness? Researchers conducting a study on healthy college students suggest that such mental cross-training does work. The notion that a few daily puzzles and quizzes sharpens the intellect and staves off cognitive decline is controversial (see Brain craze). Most research has shown that such brain games do little more than allow the participant to develop strategies for improving performance on that particular task. The improvement does not typically extend beyond the game itself. But a new study published this week in Proceedings of the National Academy of Sciences reports that a group of college students improved their performance on a pattern-recognition test — a commonly used intelligence test — after training their working memory1. Susanne Jaeggi and Martin Buschkuehl, both now at the University of Michigan in Ann Arbor, and their colleagues recruited 70 participants from the University of Bern in Switzerland, and trained them on a rigorous memory test. The test consisted of a string of events: every three seconds, a small white box would appear on the screen in varying locations while at the same time a letter of the alphabet was read aloud. © 2008 Nature Publishing Group

Keyword: Learning & Memory
Link ID: 11566 - Posted: 06.24.2010

By Pallab Ghosh A 18-year-old whose sight was failing has had his vision improved in a pioneering operation carried out by doctors at Moorfields Eye Hospital. The London researchers used gene therapy to regenerate the dying cells in Steven Howarth's right eye. As a result he can now confidently walk alone in darkened rooms and streets for the first time. Steven, from Bolton, is the third person to have the operation - doctors expect better results in future cases. Before the procedure, he could hardly see at all at night and in time he would have lost his sight completely. His condition - Lebers congenital amaurosis - was due to a faulty gene that meant that the light-detecting cells at the back of his eye were damaged and slowly degenerating further. After a few months, doctors detected some improvements. But Steven did not notice these changes until he confidently strode through a dimly-lit maze designed to test his vision. Until then he had kept walking into walls - and it would take him nearly a minute to walk a few feet. His doctors were shocked at the improvement. Professor Robin Ali, of the Institute for Ophthalmology, who led the trial, said: "To get this indication after only three patients is hugely exciting. "I find it difficult to remember being as excited as I am today about our science and what it might achieve." (C)BBC

Keyword: Vision
Link ID: 11565 - Posted: 04.28.2008

By GENE JOHNSON SEATTLE -- Timothy Garon's face and arms are hauntingly skeletal, but the fluid building up in his abdomen makes the 56-year-old musician look eight months pregnant. His liver, ravaged by hepatitis C, is failing. Without a new one, his doctors tell him, he will be dead in days. But Garon's been refused a spot on the transplant list, largely because he has used marijuana, even though it was legally approved for medical reasons. "I'm not angry, I'm not mad, I'm just confused," said Garon, lying in his hospital bed a few minutes after a doctor told him the hospital transplant committee's decision Thursday. With the scarcity of donated organs, transplant committees like the one at the University of Washington Medical Center use tough standards, including whether the candidate has other serious health problems or is likely to drink or do drugs. And with cases like Garon's, they also have to consider _ as a dozen states now have medical marijuana laws _ if using dope with a doctor's blessing should be held against a dying patient in need of a transplant. Most transplant centers struggle with the how to deal with people who have used marijuana, said Dr. Robert Sade, director of the Institute of Human Values in Health Care at the Medical University of South Carolina. © 2008 The Associated Press

Keyword: Drug Abuse
Link ID: 11564 - Posted: 06.24.2010

Kerri Smith Blind mice have been made to sense light by inserting a protein derived from algae into their eyes. A similar method could one day be used to treat certain forms of blindness in humans, the researchers hope. The light-sensitive protein, called channelrhodopsin-2 (ChR2), is used by algae to sense light for photosynthesis. Some researchers are interested in using these light-sensitive proteins to replace damaged or missing photoreceptors in animals' eyes. This happens in several human conditions, including the late stages of a relatively common form of blindness: age-related macular degeneration. At present, there are no cures for such patients, though treatments including gene therapy and laser surgery are being tested. The algae protein has been used by neuroscientists before in the lab, in order to make 'light switches' that turn neurons of interest on and off in lab animals1. But its use as a therapy against blindness is in very early stages. If the technique can be perfected, it could allow people rendered totally blind by the loss of photoreceptors able to see — albeit in black and white. © 2008 Nature Publishing Group

Keyword: Vision; Biological Rhythms
Link ID: 11563 - Posted: 06.24.2010

CHICAGO - Two of the largest and longest studies so far show a “brain pacemaker” can effectively treat depression and obsessive-compulsive disorder, researchers said on Friday. Devices implanted in the chest, with leads that send electrical impulses to parts of the brain, have already been approved to treat movement disorders, such as Parkinson’s disease, essential tremor and dystonia. Dr. Ali Rezai, head of neurosurgery at the Cleveland Clinic, who led the studies, said the technique known as deep brain stimulation helped the most severely depressed patients improve significantly. Researchers from Butler Hospital/Brown Medical School, Massachusetts General Hospital and Harvard Medical School were also involved in the depression study. Seventeen paarea of the brain and is likely to generate similar findings. He said there were no serious side effects in using the Medtronic device. The trial treating OCD included 26 patients who were followed for three years and also showed marked improvement. Copyright 2008 Reuters.

Keyword: Depression
Link ID: 11562 - Posted: 06.24.2010

By Deborah Blum Kelly Klump is a curly-haired, compact woman who is fascinated by eating disorders. Her own habits are healthy, but as a high school “peer counselor” she found herself besieged by girls struggling with the addictive starvation of anorexia nervosa and the compulsive binge-and-purge of bulimia. Now a 37-year-old associate professor at Michigan State University in East Lansing, Klump has spent the past 10 years probing the genetic influences in such illnesses and pondering a stubborn question about why biology makes women more likely targets than men for eating disorders. Lately she has revisited that frustrating question from a new angle. Working with graduate student Kristen Culbert and other colleagues, Klump published a paper in the March Archives of General Psychiatry focusing on a very specific group: females from a male-female twin pair. A few years ago this would have seemed a rather narrow approach to a widespread problem. But several recent studies now suggest that the girl twin in a mixed pair offers provocative evidence concerning the way biology shapes people before birth. Psychologists in both the United States and Europe have found that females from opposite-sex twin pairs tend to be more aggressive and adventurous, process spatial information more like men, and show more typically masculine left brain dominance during language tests. Across a range of research, these female co-twins seemed shifted toward the male end of the behavioral spectrum. © Society for Science & the Public 2000 - 2008

Keyword: Hormones & Behavior; Anorexia & Bulimia
Link ID: 11561 - Posted: 06.24.2010

WASHINGTON - Cuddling up against mother's bare skin can help tiny premature babies recover more quickly from the pain of being stuck with needles and other procedures, Canadian researchers reported on Wednesday. Babies held tightly against their mother's skin in a "kangaroo mother care" position squirmed and grimaced less than babies swaddled in blankets, the researchers found. "Skin-to-skin contact by the mother, referred to as kangaroo mother care, has been shown to be efficacious in reducing pain in three previous studies," Celeste Johnston of McGill University School of Nursing in Montreal and her colleagues wrote in the journal BioMed Central Pediatrics. But those studies involved older babies. Her team tested 61 preterm babies born between 28 and 31 weeks. Such preemies spend weeks in neonatal intensive care units and are often subjected to painful medical procedures. Parents and nurses alike find it one of the most distressing things about having an infant in the unit, the researchers said. Copyright 2008 Reuters.

Keyword: Pain & Touch
Link ID: 11560 - Posted: 04.26.2008

Although children in North America are exposed to less lead than children 30 years ago, the lead problem has not disappeared. Lead exposure in inner-city and certain minority populations remains a serious problem. Depending on the intensity of exposure and the age of the exposed person, lead can cause developmental problems, mental retardation, stunted growth, and fertility problems. Add to that a potential new effect of lead exposure: an increased risk of Alzheimer’s Disease. University of Rhode Island neurologist Nasser Zawia and colleagues have published a study in the Journal of Neuroscience, pointing to an association between lead exposure in infancy and Alzheimer’s in adulthood. “People mostly think of lead exposure as being something that only affects children, and nobody has been studying the elderly and adults to see if they’re impacted,” says Zawia. But by studying monkeys exposed to low lead levels in 1980 and 1981, Zawia and his team found evidence that childhood lead exposure could trigger growth of brain plaques associated with Alzheimer’s Disease. “What we found was simply, in the monkeys that were exposed to lead as infants, there was an increase in the expression of the genes involved in Alzheimer’s Disease and the proteins…that are part of the core of the plaques,” Zawia explains. © ScienCentral, 2000-2008.

Keyword: Alzheimers; Neurotoxins
Link ID: 11559 - Posted: 06.24.2010