By JIM HOLT Last month, a team of scientists at the University of Pennsylvania announced that it might have discovered a crucial event in the evolution of our species. The news was surprising and not a little deflating. The mutation that lifted us above the other apes had nothing directly to do with our brain. Rather, it had to do with our jaw. What led to the emergence of modern humans, in all of our culture-creating, science-discovering, globe-dominating glory, was a chance defect in a gene responsible for the formation of our jaw muscles. So, at least, the scientists speculated. Why should the size of our jaw make us the intellectual species par excellence? The next time you are chewing a mouthful of food, feel the side of your head with your fingers. You'll notice the muscles there moving as your jaw opens and closes. The jaw muscles are attached to the top of the skull. The larger those muscles are, the thicker the skull bone needs to be to anchor them. That is why apes, with their powerful, jutting jaws, have a bony crest running across the top of their heads. Anything that caused the jaw muscles to become smaller would also allow this thick bone to be shaved away over time. That, in turn, would free up space for the brain to expand into -- ''room for thought,'' as one of the scientists whimsically put it. Copyright 2004 The New York Times Company

Keyword: Evolution; Development of the Brain
Link ID: 5349 - Posted: 04.25.2004

By PAUL TAYLOR Rams, with their big horns and head-butting behaviour, have long been considered a potent symbol of masculine virility. And if you happen to be a sheep rancher, you want your rams to do their stuff when it's breeding season, or else you're not going to have any baby lambs in the spring. But ranchers have occasionally found that their prized rams just didn't perform. So, for more than a decade, scientists at a remote sheep experiment station in Dubois, Idaho, have been trying to figure out why some rams are "duds." At first, the researchers examined sperm counts and hormone levels, but they found nothing unusual. However, when they applied a little animal psychology, they concluded the non-performing rams were, to put it in human terms, gay. "You can have the best sperm in the world, but if you are not interested in inseminating females, it is not going to get delivered," said Anne Perkins, who worked at the sheep station in the early 1990s. She found that 8 to 10 per cent of the rams would shun willing females and try to mount other males. © Copyright 2004 Bell Globemedia Publishing Inc. All Rights Reserved.

Keyword: Sexual Behavior
Link ID: 5348 - Posted: 06.24.2010

A novel photoreceptor system solves one mystery while stirring up a few more By Josh P. Roberts THE EYES HAVE IT-SO DOES THE BRAIN: At top left, an X-gal stained retina from a mouse heterozygous for a LacZ knockin at the melanopsin locus reveals axons coursing toward the optic disc. At top right, a melanopsin antibody labels cell bodies, dendrites and initial axon segments of roughly 1% of ganglion cells in the rat retina. At bottom left, a coronal section from the brain of a heterozygous animal shows bilateral innervation of the suprachiasmatic nucleus (SCN). At bottom right, a stained whole brain cleared with a Benzene-based solution allows visualization of the optic nerve fibers and the optic chiasm with concomitant view of the two SCN nuclei visible in the background. I see," said the blind man. Outlandish as it seems, people lacking functional rods and cones can receive and process visual information. At least two decades ago, scientists began speculating that there may be another, "nonclassical" photoreceptor responsible for synchronizing the mammalian circadian clock with the light/dark cycle, and evidence for the idea has been building ever since.1 This issue's Hot Papers added to that body of evidence by demonstrating that melanopsin-containing retinal ganglion cells (RGCs) are intrinsically light sensitive, and project to the brain's "master clock," thus cementing melanopsin's role as a key component of a novel photoreceptor system. © 2004, The Scientist LLC, All rights reserved.

Keyword: Biological Rhythms; Vision
Link ID: 5347 - Posted: 06.24.2010

By Jane Salodof MacNeil Physically and behaviorally, few creatures have been measured, tested, and probed as much as the laboratory mouse. Yet what do scientists know about making mice happy or free of pain? Often, the answer is not nearly enough. This is a knowledge vacuum with ethical and experimental ramifications. Pain management and environmental enrichment are hot topics in laboratory animal science. They are also conundrums defying easy fixes. Researchers may want to mitigate pain and suffering in their charges, but animals of prey hide their pain. Moreover, researchers do not agree on which medicines to administer, or at what doses. Making the animals' living conditions more stimulating is also problematic. Doing what comes naturally, some social animals turn their new communal housing into boxing rings. And even if they don't, the new environment can change animal physiology in ways that confound experiments and undermine comparisons to previously obtained data. © 2004, The Scientist LLC, All rights reserved.

Keyword: Animal Rights
Link ID: 5346 - Posted: 06.24.2010

Hyperextending the neck can damage an artery A widower has urged women to be careful when visiting the hair salon after his wife died from a stroke. Malcolm Crabb believes his wife Pamela, 51, suffered so-called Beauty Parlour Stroke Syndrome after her head was bent back while being washed at a salon. Mr Crabb, 49, said he wanted to "alert others to the dangers of Beauty Parlour Syndrome, especially those with high blood pressure". "I think there should be warnings in hairdressers about it," he added. Mrs Crabb suffered her first stroke following a hair appointment in September 2000, but died last week when a second stroke proved fatal. Her grieving husband says she never fully recovered from the first stroke, which he blames on Beauty Parlour Stroke Syndrome. After the hair appointment in September 2000 Mrs Crabb felt ill, her speech became slurred and her hands became claw-like. Hospital tests showed that she had suffered a stroke. A spokesman from the Stroke Association said: "There is no real research to support it as yet but cases have been published in medical journals. "Although there is not yet a proven link there is anecdotal evidence and we would welcome research into this area." (C)BBC

Keyword: Stroke
Link ID: 5345 - Posted: 04.24.2004

An analysis suggests science really is trying to reduce animal experiments. A comparison of almost 3,000 research papers published over 30 years in major biomedical journals found a 30% fall in the number of studies using animals. The analysis by Dr Hans-Erik Carlsson and colleagues also showed increasing use of alternative testing methods, such as experiments on cultured cells. The team told the Veterinary Record there was now better reporting of the welfare of the animals kept in labs. The Uppsala University researchers conducted their investigation because they wanted to get a clearer idea of the extent to which the international "scientific culture" was adopting the principles of the so-called "three R's" - the replacement, reduction and refinement of the use of animals in experiments. Dr Carlsson's team says the changes over time are encouraging. (C)BBC

Keyword: Animal Rights
Link ID: 5344 - Posted: 04.24.2004

Jo Revill Rhythms of Life by Russell Foster; Do you want your handshake to be firm when you are first introduced to the new director? Make sure you arrange the meeting for between 6pm and 8pm. Faced with a crucial but complicated dilemma, time the decision-making moment for noon. The best hour for lovemaking is at 10pm (your wakefulness levels are at their peak) and most natural childbirth will happen between 4am and 6am, just as dawn is breaking. Our bodies move to a daily rhythm which governs every single gesture and hormone, but about which we are stupendously ignorant. Ticking away inside each cell is a highly intricate timepiece, its genetic pendulum swinging steadily on, regardless of the frenetic lives we lead. Our sluggishness, our running speed, our susceptibility to pain, our liver's ability to process alcohol - every bodily function, down to the strength of our handshake, is governed by this rhythm. Guardian Unlimited © Guardian Newspapers Limited 2004

Keyword: Biological Rhythms
Link ID: 5343 - Posted: 06.24.2010

The ability to empathise is often considered uniquely human, the result of complex reasoning and abstract thought. But it might in fact be an incredibly simple brain process ­ meaning that there is no reason why monkeys and other animals cannot empathise too. That is the conclusion of Christian Keysers of the University of Groningen in the Netherlands and his colleagues. The team used a functional MRI scanner to monitor volunteers while their legs were touched and while they watched videos of other people being touched and of objects colliding. To the team's surprise, a sensory area of the brain called the secondary somatosensory cortex, thought only to respond to physical touch, was strongly activated by the sight of others being touched. This suggests that empathy requires no specialised brain area. The brain simply transforms what we see into what we would have felt in the same situation. "Empathy is not an abstract capacity," Keysers concludes. "It's like you slip into another person's shoes to share the experience in a very pragmatic way." © Copyright Reed Business Information Ltd.

Keyword: Emotions; Pain & Touch
Link ID: 5342 - Posted: 06.24.2010

By Ed Edelson Viagra and its two newly marketed rivals, Levitra and Cialis, help men achieve erections by acting on the muscles of the penis, explained Dr. Jorge Brioni, a project leader in neuroscience research at Abbott Laboratories. The new medication, developed at Abbott and designated ABT-724, "targets the central mechanisms in the brain that control erectile dysfunction in humans," Brioni said. The drug has been successful in animal tests and has moved into human trials. The full set of trials needed for marketing approval could take seven or eight years, said James P. Sullivan, regional vice president for neuroscience discovery research at Abbott. There is a need for a different approach because the Viagra-type drugs are not effective in a substantial percentage of men who try them, Sullivan said. "In particular, the response rate is not as great as we would like in patient with diabetes," he said. Copyright © 2004 ABCNEWS Internet Ventures.

Keyword: Sexual Behavior
Link ID: 5341 - Posted: 06.24.2010

By ANDRÉ PICARD British researchers have unearthed more damning evidence that it may be inappropriate to prescribe a popular class of antidepressants to children -- unpublished data that show the drugs can increase the risk of suicide and suicidal thoughts. The research shows that published studies about drugs such as Paxil and Zoloft -- known as selective serotonin reuptake inhibitors -- paint far too rosy a picture of the benefits. The only drug that consistently showed benefits in treating children with depression was Prozac, the researchers said. Based on the information, it is "inappropriate" for physicians to rely on published research and they should rethink how they treat patients for depression, said Craig Whittington of the National Collaborating Centre for Mental Health in London. The research is published in today's edition of the medical journal The Lancet. Last year, more than 450,000 Canadians under the age of 19 were treated by a physician for depression. Antidepressants were prescribed to 75 per cent of them. © Copyright 2004 Bell Globemedia Publishing Inc.

Keyword: Depression; Development of the Brain
Link ID: 5340 - Posted: 06.24.2010

Drug companies have been accused of failing to publish drug trials which do not give the "right" result. Regulatory bodies found it harder to make balanced decisions when negative information was not available, the Lancet medical journal said. Published research suggested a type of antidepressant drug was safe for children, but unpublished data indicated it was not, a study showed. The pharmaceutical industry said it was taking steps to solve the problem. A study by the National Collaborating Centre for Mental Health in London looked at previous research on selective serotonin reuptake inhibitors (SSRIs) for children. It found that in published studies, all SSRIs appeared to have a favourable ratio of risk to benefit. But, after also looking at unpublished trials, it was found that, with the exception of fluoxetine, the risks exceeded the benefits. (C)BBC

Keyword: Depression; Development of the Brain
Link ID: 5339 - Posted: 04.23.2004

By THE ASSOCIATED PRESS LONDON, — School programs discouraging carbonated drinks appear to be effective in reducing obesity among children, a new study suggests. A high intake of sweetened carbonated drinks probably contributes to childhood obesity, and there is a growing movement against soft drinks in schools. But until now there have been no studies showing that efforts to lower children's consumption of soft drinks would do any good. The study, outlined this week on the Web site of The British Medical Journal, found that a one-year campaign discouraging both sweetened and diet soft drinks led to a decrease in the percentage of elementary school children who were overweight or obese. The improvement occurred after a reduction in consumption of less than a can a day. Representatives of the soft drink industry contested the implications of the results. Copyright 2004 The New York Times Company |

Keyword: Obesity
Link ID: 5338 - Posted: 06.24.2010

People linked to animal experimentation who have suffered attacks and intimidation from animal rights extremists have banded together to lobby the UK government for changes in the law. The Victims of Animal Rights Extremism (VARE) group was launched at the British Parliament on Thursday. The 100-strong body of people who have suffered violence and harassment wants the government to crack down on the problem of extremism. "I think there's a tremendous and desperate need for an organisation like this to exist," says Mark Matfield, director of the Research Defence Society, who set up VARE. The voluntary group, which is currently not listed as a charity so that its address does not have to be revealed, aims to also provide support and help for victims of extremism. "The government and police don't seem to be solving this problem," says Matfield. He adds the situation may even be worsening. © Copyright Reed Business Information Ltd.

Keyword: Animal Rights
Link ID: 5337 - Posted: 06.24.2010

Adults are as scatterbrained as kids. And the disorder may be rooted in basic biology By Marianne Szegedy-Maszak When Nancy Quinlan was in her early 20s, her 6- year-old son was bouncing off walls. His high intelligence simply couldn't compensate for his utter lack of self-control, and no form of discipline seemed to help. When she finally, in desperation, took him to a doctor, she was told that her son had something called minimal brain dysfunction with hyperactivity. The doctor warned her, however, that nobody--not family, not teachers, not even pediatricians--would take the little-known diagnosis seriously. He nonetheless gave Quinlan a prescription for Ritalin to help calm her son's fevered mind. That was 40 years ago, and that physician was way ahead of his time. Quinlan was, too, in a way: As she filled her son's prescription, she began wondering if this pediatric drug might possibly help her as well. An intelligent woman, she had gone through her school days in utter agony, always struggling to pay attention or to organize herself and her thoughts. She suffered from low self-esteem, and her only pleasure came from thrill-seeking activities like drag racing. Was it possible that she shared her son's affliction? She took a dose of the Ritalin and was stunned. She remembers thinking: "This one pill is what I have been looking for all my life. I can actually concentrate." Copyright © 2004 U.S.News & World Report, L.P.

Keyword: ADHD
Link ID: 5336 - Posted: 06.24.2010

By Larry O'Hanlon, Discovery News A new study by fertility experts on how higher temperatures could have led to too many male and not enough female baby dinos points to another way the dinos could have been wiped out — without an asteroid impact. "Crocodiles and a lot of reptiles use egg incubation temperature as a sex determining factor," said David Miller of the University of Leeds' Department of Pediatrics, Obstetrics and Gynaecology in England. He is the co-author of a paper on the matter in the current issue of Fertility and Sterility. The warmer the eggs, the more males pop out, said Miller. And if the global climate were warming at the end of the Cretaceous 65 million years ago, it could have led to too many males. That, in turn, would have seriously thrown dinosaur populations out of whack and could have wiped out many species. Copyright © 2004 Discovery Communications Inc.

Keyword: Sexual Behavior; Evolution
Link ID: 5335 - Posted: 06.24.2010

Discovery might help cocaine addicts kick the habit. MICHAEL HOPKIN Researchers have been able to lessen cocaine cravings in rats by blocking certain signals in their brains. The discovery could eventually help recovering human addicts to stave off withdrawal symptoms, says Peter Kalivas of the Medical University of South Carolina in Charleston, who led the work. Current therapies rely on behavioural techniques such as avoiding tempting situations. The researchers studied the brains of cocaine-addicted rats that had been denied the drug for three weeks. The animals produced increased levels of a brain chemical called AGS3, the team reports in the latest issue of Neuron1. AGS3 is produced in a region called the prefrontal cortex, which is linked to the brain's motivational circuitry, says Kalivas. "It is the cortex that decides whether you get cravings or not," he says. © Nature News Service / Macmillan Magazines Ltd 2004

Keyword: Drug Abuse
Link ID: 5334 - Posted: 06.24.2010

The scientists who cloned Dolly the sheep are applying for a licence to clone human embryos. Professor Ian Wilmut, of the Roslin Institute in Edinburgh, wants to use cloned human embryos to study motor neurone disease (MND). His application to the Human Fertilisation and Embryology Authority is expected to provoke criticism that testing human embryos is immoral. Therapeutic cloning for research has been legal in the UK since 2001. It is designed purely for research. Professor Wilmut has stressed that his team has no intention of producing cloned babies, and said the embryos would be destroyed after experimentation. He told the BBC: "Because at this early stage the embryo does not have that key human characteristic of being aware to me it would be immoral not to take this opportunity to study diseases." Until recently, Professor Wilmut had said he would not work with human embryos. (C)BBC

Keyword: ALS-Lou Gehrig's Disease ; Stem Cells
Link ID: 5333 - Posted: 04.21.2004

Girls study mothers, while boys play around David Perlman, Chronicle Science Editor Chimpanzees and humans, close relatives on the evolutionary tree, are surprisingly similar when it comes to gender differences in early learning ability, according to a young scientist following in the footsteps of chimp research pioneer Jane Goodall. Studies of children have long recognized that young girls learn fine motor skills like writing earlier and more effectively than boys. Now, Elizabeth Lonsdorf has found a corollary among the chimps she studies in Tanzania's Gombe National Park, where Goodall first demonstrated similarities between human and chimp behavior. When it comes to using tools for extracting luscious termites from their jungle mounds, girl chimps study their mothers carefully and succeed, while boy chimps prefer to play games with each other, rarely study and never catch as many of the fat-and-protein-rich insects, Lonsdorf's research discovered. "A sex-based learning difference may therefore date back at least to the common ancestor of chimpanzees and humans," she speculates in a report in the April 16 issue of the journal Science. ©2004 San Francisco Chronicle

Keyword: Sexual Behavior
Link ID: 5332 - Posted: 06.24.2010

Birds are pretty far away from humans on the evolutionary ladder. But scientists have found that songbirds have a gene that is important in human language learning. "There is a connection between human language and bird vocal imitation at the genetic level," says Erich Jarvis, a neurobiologist at Duke University. "What we discovered is that songbirds and other birds that have the ability to imitate sounds contain a gene called FoxP2 that is know to be involved in human language. It's the first time we have a gene that we can study now in songbirds that we know is linked to language in humans." The FoxP2 gene was found to be involved in human language several years ago. Its mutation produces an inherited language deficit called an oral apraxia. People with this deficit have an inability to pronounce words correctly, form them into sentences that are grammatically correct, and understand complex language. "We decided to look for this gene in other species of animals who can actually imitate sounds like humans can do," explains Jarvis. "And this is a very rare trait. Only hummingbirds, parrots, and songbirds, as well as bats and dolphins, have this ability. So we studied birds, and what we found is that birds also have this same gene." © ScienCentral, 2000-2004.

Keyword: Language; Genes & Behavior
Link ID: 5331 - Posted: 06.24.2010

DURHAM, N.C. -- Prenatal exposure to nicotine inflicts lasting damage that might leave the brain vulnerable to further injury and addiction upon later use of the drug, according to animal research conducted by Duke University Medical Center pharmacologists. The team found in rat studies that exposure to nicotine in fetal development alters the brain structures and brain cell activity in regions critical to learning, memory and reward. In turn, those changes influence nicotine's effects on the brain during adolescence, a time when many smokers first take up the habit, the team found. The study in rats might provide a biological explanation for the high incidence of smoking among teens whose mothers smoked during pregnancy, the researchers said. "Teens whose mothers smoked during pregnancy can show signs of nicotine dependence and withdrawal after just a handful of cigarettes," said Theodore Slotkin, Ph.D., professor of pharmacology, psychiatry and neurobiology at Duke. "Our study suggests a biological mechanism to explain that." © 2001-2004 Duke University Medical Center.

Keyword: Drug Abuse; Development of the Brain
Link ID: 5330 - Posted: 06.24.2010