By Robert Sanders BERKELEY – Parents whose grown children have not yet flown the nest can only sympathize with the Western bluebird. While female fledglings fly off on their own in late summer, their brothers typically hang around through the winter and into the next breeding season, living off the bounty of their parents' larder. As with humans, though, as the money runs low, the kids split, according to a new study by scientists at the University of California, Berkeley. Janis Dickinson, a research associate with the Museum of Vertebrate Zoology at UC Berkeley and a newly appointed associate professor of natural resources at Cornell University, discovered parallels between human and bird families while studying the evolution of delayed dispersal, or natal philopatry - the tendency for offspring to stay at or near home rather than look for a new place to live and breed. Such behavior is common among cooperatively breeding birds as well as humans, and, at least in birds, it leads to close-knit families. Copyright UC Regents

Keyword: Sexual Behavior; Evolution
Link ID: 8063 - Posted: 06.24.2010

An emotional buffer zone in the brain may not be working as it should in women who experience premenstrual moodiness, a new study suggests. David Silbersweig and colleagues at the Weill Medical College of Cornell University, New York, US, used functional magnetic resonance imaging to scan the brains of 12 women whose moods remained steady throughout their menstrual cycles. From 1 to 5 days before menstruation, and 8 to 12 days after, the women’s brains were scanned as they were shown printed words with either negative, neutral, or positive connotations – words like “rape”, “cancer”, “bookcase”, “rotate”, “gentle” and “delighted” – to engage the emotion-processing part of the brain. At the same time, the women were motivated to complete a simple cognitive task. The scans showed that the orbitofrontal cortex – part of the brain involved in controlling emotions and regulating motivation – was more active during the task in the days before menstruation. After menstruation, that part of the brain was relatively inactive during the task. Silbersweig says that the difference in brain activity may “buffer” hormonal changes in these women, helping them to maintain a consistent emotional state. “Because this area is kicking in, these women are able to avoid moodiness,” he says. © Copyright Reed Business Information Ltd.

Keyword: Hormones & Behavior; Emotions
Link ID: 8062 - Posted: 06.24.2010

By Michelle Roberts, BBC News health reporter Scientists say they have proof that the sex of the brain makes men and women more prone to different diseases. Doctors know that women are more likely than men to have depression, anxiety or an eating disorder, while men are at higher risk of Parkinson's disease. Post-mortem and brain imaging studies show that male and female brains are physically different. Now scientists say they can to link the two together and suggest future disease cures may be "gender-specific". The sex of a brain is decided in the mother's womb and depends, among other factors, on hormone levels. Higher levels of testosterone makes a male brain and oestrogen a female one. Professor Dick Swaab from The Netherlands Institute for Brain Research in Amsterdam, said the proof for this comes from studies of transsexuals - people who know, often from a very early age, that they are born in the wrong gender body. "The theory is that the sex difference in the sex organs develops early in pregnancy - in the first few months while in utero - while sexual differentiation of the brain occurs later in the second half of pregnancy and postnatally." That would mean certain factors could interfere with the sexual differentiation of the sex organs and brain in an independent way because there is a time lapse between the two. (C)BBC

Keyword: Sexual Behavior; Hormones & Behavior
Link ID: 8061 - Posted: 10.24.2005

By PATRICIA COHEN Can the generally disappointing crop of national leaders today be attributed to the Prozac Generation's addiction to cheeriness? That is one strain of thought in Joshua Wolf Shenk's book, which argues that Abraham Lincoln's lifelong struggle with depression was responsible for his becoming one of America's greatest presidents. The idea that suffering fuels creativity and wisdom is an old one, but in a country where 25 million people take antidepressants, it has its limits. The emotionally suffering artist stokes our romantic imagination; the emotionally suffering politician evokes panic. Who wants to think about Eeyore nose to nose with bin Laden? But depression, Shenk says, has gotten bad press. This is not a contrarian's gimmick; he has firsthand knowledge. In previous writings about his own depression, Shenk credited it with shaping his personality. That he would then conclude the same about his hero should not be all that surprising. If "Lincoln's Melancholy," a thoughtful but uneven book, is the product of a particularly personal experience, it is also the result of the latest currents in psychology and Lincoln studies. After years of dismissing the significance of Lincoln's inner life, scholars have reversed course in the last two decades. (A history of this history is nicely summarized in the afterword.) And in a series of 1998 lectures at Harvard, Andrew Delbanco linked Lincoln's private despair with his public work. "The lesson of Lincoln's life," he said, is that "a passion to secure justice" can be a "remedy for melancholy." Copyright 2005 The New York Times Company

Keyword: Depression
Link ID: 8060 - Posted: 10.24.2005

For the first time, researchers have found evidence of a split in the migration pattern of a species of bird, a behavior that some theorize could lead to a new species. Bands of the European blackcap, which typically breed in Austria and Germany, have begun flying to two separate locations for the winter: one group goes south to Portugal, Spain and North Africa, whereas the other flies north to Britain and Ireland. Scientists studying the two groups found that the birds that wintered together in the north tended to mate with each other once they arrived back in Austria and Germany. These birds also produced more young than those that wintered in the south, which could improve their evolutionary chances of diverging. "The 'British' birds tend to arrive on the breeding grounds earlier than the southern ones, allowing them to gain access to the best territories--a bit like getting their towels on the best sun-loungers first," said ornithologist Stuart Bearhop of the Queen's University Belfast, whose team published its results in the current issue of Science. The scientists arrived at their conclusions by studying birds from multiple sites over two winters and two summers. In the winters, the team analyzed the ratio of the chemical signatures in claw clippings from the birds, which can be tied to the same chemical signatures in rain from specific regions. © 1996-2005 Scientific American, Inc

Keyword: Evolution; Sexual Behavior
Link ID: 8059 - Posted: 06.24.2010

STANFORD, Calif. - A gene that regulates dopamine levels in the brain is involved in the development of schizophrenia in children at high risk for the disorder, say researchers at the Stanford University School of Medicine, Lucile Packard Children's Hospital and the University of Geneva. The finding adds to mounting evidence of dopamine's link to psychiatric and neurological disorders. It may also allow physicians to pinpoint a subset of these children for treatment before symptoms start. "The hope is that we will one day be able to identify the highest-risk groups and intervene early to prevent a lifetime of problems and suffering," said Allan L. Reiss, MD. "As we gain a much better understanding of these disorders, we can design treatments that are much more specific and effective." Reiss is the Robbins Professor of Psychiatry and Behavioral Sciences at Stanford and director of the school's Center for Interdisciplinary Brain Sciences Research. He is also a child and adolescent psychiatrist at Packard Children's Hospital at Stanford. The research, which will be published online Oct. 23, will appear in print in the November issue of Nature Neuroscience.

Keyword: Schizophrenia; Genes & Behavior
Link ID: 8058 - Posted: 10.24.2005

Experts have launched a course to teach the family members of young people with eating disorders how to offer care and support. Over a million people in the UK have an eating disorder, many of them teenagers and some children as young as seven. Effective treatment early on can mean a successful outcome in 90% of cases, but often it is difficult for loved ones to know what to do for the best. King's College London has begun a course to give carers necessary skills. The Collaborative Caring Course teaches the necessary skills to understand eating disorders, such as anorexia and bulimia, and the consequential behavioural changes. It is hoped it will help family members deal with the impact eating disorders have on their lives as well as to inspire change in the sufferer. Professor Janet Treasure from The Eating Disorder Research Unit, who is running the free course, said she hoped to dispel common eating disorder myths. These include the misconception that families, in particular mothers, are responsible for their daughter developing an eating disorder; that people with anorexia nervosa choose to have their illness and that people with eating disorders are trying to punish their parents. "Understanding and support are vital," she said. (C)BBC

Keyword: Anorexia & Bulimia
Link ID: 8057 - Posted: 10.22.2005

By GINA KOLATA Dr. Lewis G. Maharam, the medical director for the New York City Marathon and marathons in San Diego, Phoenix, Nashville and Virginia Beach, said he was taking every opportunity this year to educate runners about the biggest threat to their lives on race day - drinking too much water. He knows the danger: in their zeal to avoid becoming dehydrated, runners may end up drinking so much that they dilute their blood. Water rushes into cells, including cells of the brain. The swollen brain cells press against the skull, and the result can be fatal. The resulting condition is known as hyponatremia - too much water. "There are no reported cases of dehydration causing death in the history of world running," Maharam said. "But there are plenty of cases of people dying of hyponatremia." No one knows how many have died, said Dr. Arthur Siegel, the chief of internal medicine at McLean Hospital in Belmont, Mass., and the designated hyponatremia team leader for recent Boston Marathons. But he said that perhaps a dozen hyponatremia deaths had been recognized, according to informal communications among doctors at recent marathons. Copyright 2005 The New York Times Company

Keyword: Miscellaneous
Link ID: 8056 - Posted: 10.22.2005

By LIZETTE ALVAREZ AS marriage proposals go, this one was textbook: A Caribbean cruise, a night bursting with stars, a pitch-perfect dinner and then, after retiring to a private balcony, a bottle of Dom Pérignon. Ed Silcox Jr. dropped to one knee and presented an impeccable diamond ring to the bride-to-be, Johanna Murtha, who stifled tears. They scurried to bed, blissfully falling asleep in each other's arms. Then the farce began: Mr. Silcox, 46, started to snore: a cabin-rattling crescendo that built from minor rasp to mind-blowing snort. The snores blew past his new fiancée's foam earplugs, defied a stack of over-the-head pillows and rumbled down hallways. In no time Mr. Silcox was exiled to the balcony, where he slept night after night, braving the wind, the rising sun and a stream of dirty water from on high (as the deck hands cleaned the ship). A hotel in Puerto Rico offered little respite. In her desperation, Ms. Murtha, 40, chose to nap by the pool, in a howling thunderstorm, rather than snooze in bed next to her fiancé. "We spent every night apart and fought virtually every night of the week," said Ms. Murtha, now happily Ms. Murtha-Silcox, who lives outside Philadelphia. "By the end of the cruise I was thinking, 'What did I say yes for?' We were exhausted. Our eyes were falling out of our heads." Copyright 2005 The New York Times Company

Keyword: Sleep
Link ID: 8055 - Posted: 10.22.2005

La Jolla, CA - Delving ever deeper into the intricate architecture of the brain, researchers at The Salk Institute have now described how two different types of nerve cells, called neurons, work together in tiny sub-networks to pass on just the right amount and the right kind of sensory information. Their study, published online by Nature Neuroscience, depicts how specific types of inhibitory neurons in the visual cortex of a rat brain are wired to, and "talk" with, discrete excitatory neurons. They also show how that "conversation," aimed at keeping the right balance of chemical signals, often excludes surrounding neurons. "The inhibitory neurons are not just brakes, they can also be used to steer." said co-author Ed Callaway, Ph.D., associate professor in Salk's Systems Neurobiology Laboratories. For example, in vision, inhibitory responses in the visual cortex help people to focus on what they want to see, rather than all there is to see, he explained. This new study is filling in the picture of how the brain is organized into "smart" efficient networks, and researchers hope that details of this complex design might, one day, uncover the roots of such neurological diseases as schizophrenia. "We know already that schizophrenia is a problem with organization of inhibitory circuits of neurons, and now we are uncovering how these specialized nerve cells work together and with other neurons," Callaway explained.

Keyword: Vision
Link ID: 8054 - Posted: 10.22.2005

Christen Brownlee Two independent groups of scientists have devised ways to isolate embryonic stem cells from mice without destroying viable embryos. These new methods are intended to satisfy the ethical concerns of people who oppose destroying human embryos to do research or treat disease. Unlike any cell known in adults, embryonic stem cells can morph into virtually any of the body's cell types, such as nerve, muscle, or heart. Many researchers have proposed exploiting this unique capability to make new cells for the treatment of injuries or diseases such as Parkinson's disease (SN: 4/2/05, p. 218: http://www.sciencenews.org/articles/20050402/bob10.asp). However, to isolate a new line of embryonic stem cells, scientists have had to first destroy an early embryo. "Many people, including the President, are concerned about destroying life in order to save life," says Robert Lanza of Advanced Cell Technology in Worcester, Mass. Seeking to resolve this dilemma, Lanza and his colleagues looked to a technique commonly used to diagnose genetic diseases in embryos. Known as pre-implantation genetic diagnosis, the procedure removes one cell from an eight-cell-stage embryo and examines its DNA for defects. The remaining seven-cell embryo, after being implanted in the mother's womb, can develop into a normal baby. ©2005 Science Service.

Keyword: Stem Cells; Regeneration
Link ID: 8053 - Posted: 06.24.2010

By Lise Stevens, Contributing Writer The addition of testosterone to hormone therapy in women after menopause enhances their sexual function. However, it may also reduce HDL cholesterol (the “good” cholesterol) in women, according to a systematic review of current evidence. “If the reduction in HDL had been associated with an increase in triglycerides [fatty acids] or LDL cholesterol it would be of great concern,” said Dr. Susan Davis, professor of medicine at Monash University, Melbourne, Australia, and study co-author “However, as an isolated finding the significance is difficult to interpret.” She added, “Testosterone has not been found to alter other coronary heart disease risk factors.” The review appears in the most recent issue of The Cochrane Library, a publication of The Cochrane Collaboration. The study team reviewed 23 randomized clinical trials involving 1,957 patients who had testosterone added to their hormone replacement therapy (either estrogen or combined estrogen/progestin) for an average of six months. Testosterone was given orally in a majority of the studies in doses of either 1.25 mg. or 2.5 mg. Participants completed questionnaires that measured their sexual activity and libido, and were assessed for other side effects. Health Behavior News Service Washington, DC © 2005

Keyword: Sexual Behavior; Hormones & Behavior
Link ID: 8052 - Posted: 06.24.2010

People could have an immunity to vCJD and similar diseases after persistent exposure to milder strains of the agent that causes them, scientists suggest. Experts at Yale University and Nagasaki University medical schools carried out studies on cells. Writing in Science magazine, they said regular doses of the weaker infection appeared to offer protection. A UK expert said further understanding of how the effect works could lead to a preventative therapy being developed. It might also help to explain why fewer people than predicted have died from vCJD. The US and Japanese researchers also put forward the theory that the diseases are caused by viruses. Misfolded proteins called prions are present in brain and nerve tissue infected with vCJD, and related diseases known as transmissible spongiform encephalopathies (TSEs). Other TSEs include classic CJD, BSE, which infects cattle, and scrapie, which infects sheep. But there is doubt as to whether prions are the cause of these diseases, or simply the result of them. Earlier research on animals showed a weaker strain of CJD appeared to offer protection against a more destructive strain. (C)BBC

Keyword: Prions
Link ID: 8051 - Posted: 10.22.2005

Scientists are developing a cochlear implant which could allow deaf people to hear music. Existing implants allow people to listen easily to speech, but not music. But a team at the UK's National Physical Laboratory have developed a device with a wider frequency range, which improves musical appreciation. New Scientist magazine reports the whole implant could be put into the ear - current models require people to wear a box behind their ears. The cochlea in the ear contains fluid and hairs which vibrate in response to sounds. These hairs can stop vibrating, meaning people go deaf. It can happen at any age but can be particularly difficult for children as it affects their ability to do well at school and socialise. Cochlear implants currently involve putting an electrode inside the ear and an external box, which contains a microphone to pick up the sound, converts it from radiowaves into electrical signals and contains batteries to power the implant. Conventional hearing aids simply amplify sound rather than making it clearer. (C)BBC

Keyword: Hearing
Link ID: 8050 - Posted: 10.20.2005

Researchers at the University of Toronto (U of T), Capital Health's Stollery Children's Hospital in Edmonton, Toronto's Hospital for Sick Children and their international collaborators have discovered a genetic abnormality that causes a type of language impairment in children – a discovery that could lead to isolating genes important for the development of expressive language. A study published in the Oct. 20 issue of the New England Journal of Medicine outlines the discovery of a genetic abnormality in a nine-year-old boy with learning difficulties and speech problems from northern Alberta. By using some of the latest genetic screening methods designed to look for differences in the amount of DNA in particular chromosomes, the researchers discovered that the boy carries additional copies (termed duplication) of around 27 genes on chromosome 7. This is only the second instance of the identification of a single chromosome region linked to specific language impairment. The boy can understand what is said to him at the level of a seven-year-old but his expressive language and speech are at the level of a two-and-a-half-year-old. "Our results show that changes in the copy number of specific genes can dramatically influence human language abilities," says senior author Lucy Osborne, a U of T professor of medicine. "Based on our findings, we are expanding the study to assess the frequency of this DNA duplication in children with expressive language delay."

Keyword: Language; Genes & Behavior
Link ID: 8049 - Posted: 06.24.2010

We all know the site of a tragic accident. A four by four tossed over a highway barrier. A white sheet on the ground. Police with heads bent. As we pass, it seems like the most courteous action would be to avert our eyes, but still we glance over to the awful scene. Vanderbilt University psychologist David Zald says that's dangerous because, what he calls "emotional" images -- like car accidents, a gruesome murder scene, or a bit of pornography -- can briefly blind us to everything else around us, limiting our senses and potentially putting us at risk. "When [visual] information comes into the brain it has to get funneled through a relatively small area… only so much information can pass though at a time," explains Zald. "So what happens is, if there's a piece of emotional information, it basically gets jammed into the space… and nothing else is passing through." Zald and a group of colleagues based at Yale University report in the November issue of Psychonomic Bulletin and Review that they trained 21 people to spot a target image among a series of pictures flying by on a computer screen at a rate of 10 pictures per second. The target image is what the researchers call a "neutral" image, such as a picture of a building or a landscape. Study participants had to determine if the target image was rotated to the left or the right. © ScienCentral, 2000-2005.

Keyword: Vision; Emotions
Link ID: 8048 - Posted: 06.24.2010

Researchers are now understanding in greater detail the molecular machinery underlying the short-term brain changes that produce the high of cocaine, as well as the longer-term changes behind addiction. Their findings offer hope for targeted drugs that can short-circuit that addiction machinery. In the October 20, 2005, issue of Neuron, researchers led by Eric J. Nestler and Arvind Kumar of The University of Texas Southwestern Medical Center have pinpointed a key molecular mechanism by which genes are switched on in the brain that govern both short-term and long-term effects of cocaine. Such activation is called transcriptional activation because it induces the gene to begin making copies of itself into messenger RNA that trigger protein production. In their experiments, the researchers studied a process called "chromatin remodeling"--in which the histone proteins enfolding genes are chemically altered to render the genes active. They administered to rats both short-term, acute cocaine doses and long-term, chronic cocaine and analyzed the alteration of the histones affecting specific genes involved in cocaine response in the brain.

Keyword: Drug Abuse; Genes & Behavior
Link ID: 8047 - Posted: 10.20.2005

Fetal alcohol syndrome (FAS), a disorder that is indicated by distinct facial characteristics, growth retardation, and poor intellectual and attentional function, can occur when mothers drink alcohol heavily during pregnancy. A new study in the October issue of The Journal of Pediatrics shows that prenatal alcohol exposure can also affect an infant's visual acuity or sharpness of vision. Sandra W. Jacobson, Ph.D. and colleagues from Wayne State University and University of Cape Town evaluated 131 infants of mixed ancestry in Cape Town, South Africa. After interviewing each mother to ascertain her alcohol consumption during pregnancy, the authors tested the visual acuity of the infants at 6 ½ months of age using the Teller Acuity Cards (TAC) Test, which is comprised of gray cards with a concentration of vertical black and white stripes on the left or the right side. An examiner looked through a peephole in the center of the card to determine where the infant was looking. Poor visual acuity was indicated when the infant was not looking at the side containing the lines. Of the infants examined, 22 met the criteria for being diagnosed with FAS, and their visual acuity was significantly poorer than those without FAS. 27% of the infants with FAS scored below the fifth percentile, as opposed to the 9% of the infants without FAS. However, half of the infants with low TAC scores who did not meet the criteria for full FAS were born to mothers who reported binge drinking (greater than 5 drinks per occasion) during pregnancy.

Keyword: Drug Abuse; Vision
Link ID: 8046 - Posted: 10.20.2005

By GARDINER HARRIS The use of sleeping pills among children and very young adults rose 85 percent from 2000 to 2004, in yet another sign that parents and doctors are increasingly turning to prescription medications to solve childhood health and behavioral problems. And about 15 percent of people under age 20 who received sleeping pills were also being given drugs to treat attention deficit and hyperactivity disorder, according to the study by Medco Health Solutions, a managed-care company that makes estimates about medication use in the whole population based on extrapolations from its own data. Drugs used to treat attention disorders can cause insomnia. Few of the prescriptions given to children and young adults have the approval of the Food and Drug Administration because no sleep medication has been approved for use in children under 18. Still, doctors commonly use medications for patients and disorders for which the drugs have never received formal approval, particularly when those patients are children. Dr. Robert Epstein, Medco's chief medical officer, said, "It leads you to wonder whether these children are being treated for insomnia caused by hyperactivity or whether the medication itself causes the insomnia." The use of sleeping medicines among adults doubled from 2000 to 2004, Medco found. Copyright 2005 The New York Times Company

Keyword: Sleep
Link ID: 8045 - Posted: 10.19.2005

By BENEDICT CAREY They seem almost alive: snapshots of the living human brain. Not long ago, scientists predicted that these images, produced by sophisticated brain-scanning techniques, would help cut through the mystery of mental illness, revealing clear brain abnormalities and allowing doctors to better diagnose and treat a wide variety of disorders. And nearly every week, it seems, imaging researchers announce another finding, a potential key to understanding depression, attention deficit disorder, anxiety. Yet for a variety of reasons, the hopes and claims for brain imaging in psychiatry have far outpaced the science, experts say. Dr. Helen Mayberg of Emory found a baffling pattern of brain activity. After almost 30 years, researchers have not developed any standardized tool for diagnosing or treating psychiatric disorders based on imaging studies. Copyright 2005 The New York Times Company

Keyword: Depression; Brain imaging
Link ID: 8044 - Posted: 10.19.2005