Like a stereotypical husband who pretends not to hear his wife berating him, some male songbirds show no signs of recognizing the call of their long-term mate in laboratory settings. But recent work with these animals finds that they can, in fact, differentiate their mate's voice but will react to it only in certain social situations. Zebra finches are monogamous songbirds from Australia that fly in large flocks. As a result, couples routinely lose visual contact of each other and use calls to keep in touch. Whereas the female zebra finch clearly responds to the sound of her partner, the reciprocal behavior had not been observed in the male. Clémentine Vignal of Jean Monnet University in Saint-Etienne, France, and her colleagues acoustically analyzed the calls of seven female finches to see whether they had distinguishing characteristics. The results, published today in the journal Nature, demonstrated significant variation in the songs of the female birds, implying that the males could in all likelihood identify their sweethearts if they put their minds to it. To test this hypothesis, the researchers observed the reactions of male zebra finches while recordings of their mates were played back. Unlike previous setups in which the male was alone in a cage, the team placed other zebra finches nearby. As in previous experiments, the male made no display of recognition to his mate's voice in the company of either two males or a male and female who were not mates. Interestingly, however, when a mated couple was in the next cage, the male made it clear that he knew his mate's voice by nearly doubling the rate of his own calls. © 1996-2004 Scientific American, Inc

Keyword: Sexual Behavior
Link ID: 5865 - Posted: 06.24.2010

Six-year-old Nathan Neisinger suffered serious burns when he accidentally pulled a pot of boiling water onto himself. "He had third degree burns and they were over 31 percent of his body," says his mother, Heidi. "His whole entire chest, his back, his legs, part of his foot, had third degree burns all over them. They had to do skin grafting; they had to take skin off of his behind, off of the back of his legs." Besides skin grafts, Nathan has endured months of wound care and more pain than safe doses of narcotics can alleviate. "The care is very often more painful than the injury itself," says David Patterson, a psychologist and pain expert at Harborview Medical Center in Seattle, where Nathan spent 51 days after being airlifted there for his injuries. "Typical care involves removing bandages and then scrubbing the wound, and for some patients, you do that once or twice a day, for days, weeks, and even months." And then there was the physical therapy to stretch his scarred skin. "The actual process of going through that physical therapy is often very extensive," says Patterson. "You can hear some ripping and cracking. It can be anxiety-producing to anyone, much less a six-year-old." © ScienCentral, 2000- 2004.

Keyword: Pain & Touch
Link ID: 5864 - Posted: 06.24.2010

Howard Hughes Medical Institute (HHMI) researchers have identified subtle defects in a single gene that underlie a hereditary form of age-related macular degeneration, the leading cause of irreversible vision loss in the developed world. Although the genetic mutations discovered by the researchers affect only about two percent of patients with the disorder, the findings offer important insights for researchers who seek to understand age-related macular degeneration (AMD). “The clinical entity that we call AMD is actually as many as fifty diseases,” said the study's lead author, HHMI investigator Edwin M. Stone, who is at the University of Iowa Carver College of Medicine. “They simply look so similar that clinicians call them the same thing. Because of such complexity, we don't understand the molecular mechanisms of the disease very well, and this has limited our ability to develop preventive therapy for it. “Looking for genetic causes of AMD is potentially very meaningful because it will help us identify the mechanisms of the disease,” he said. “Knowing the genetic bases of AMD would also enable us to create an animal model that could be used to test therapies. And, if we understood several of the mechanisms, we could potentially divide the patient population into clinically relevant subgroups, so that we could direct specific treatments to those most likely to benefit from them.” © 2004 Howard Hughes Medical Institute.

Keyword: Vision; Genes & Behavior
Link ID: 5863 - Posted: 06.24.2010

The hand you favour as a 10-week-old fetus is the hand you will favour for the rest of your life, suggests a new study. The finding comes as a surprise because it had been thought that lifelong hand preferences did not develop until a child was three or four years old. A team led by Peter Hepper of the Fetal Behaviour Research Centre at Queen's University, Belfast in the UK reached this conclusion after studying ultrasound scans of 1000 fetuses. In one study, nine out of 10 fetuses at 15 weeks' gestation preferred to suck their right thumbs. Hepper's team followed 75 of those fetuses after birth, and found that at 10 to 12 years old all 60 of the right thumb-suckers were right-handed, while 10 of the 15 left thumb-suckers were left-handed and the rest right-handed. At 10 weeks old, even before they suck their thumbs, fetuses wave their arms about. A second study found that most prefer to wave their right arm, a preference that persisted until 24 weeks, after which the fetus is too cramped to move. Hepper reported the findings at the Forum of European Neuroscience in Lisbon, Portugal, earlier in July. © Copyright Reed Business Information Ltd.

Keyword: Laterality
Link ID: 5862 - Posted: 06.24.2010

Michael Hopkin It is good political strategy to surround your territory with the weak. And it turns out that a species of Australian crab is expert at working out how worthwhile it is to protect its feeble neighbours for the sake of a quiet life. If the next-door territory comes under attack, a crab will fight to help defend it, report Patricia Backwell and Michael Jennions of the Australian National University in Canberra. But the crustacean weighs up the odds first, and only provides backup for neighbours who are smaller than itself. The researchers studied fiddler crabs (Uca mjoebergi) living on seaside mudflats in Darwin, Australia. These crab communities are densely packed and the average male marshals a territory just 10 centimetres across. "Everyone knows his neighbour," says Backwell. But not all males boast a bachelor pad, and lack of one can seriously hamper success with the ladies. Homeless crabs roam the community, attacking homeowners and attempting to steal their patch. ©2004 Nature Publishing Group

Keyword: Aggression; Evolution
Link ID: 5861 - Posted: 06.24.2010

Helen Pilcher Size may matter after all, when it comes to IQ. A brain imaging study suggests that human intellect is based on the volume of grey matter in certain brain regions, challenging alternative views about the basis of intelligence. Researchers have been trying to pinpoint the biological roots of intelligence for decades. More than 25 years ago, a weak correlation was found between IQ and overall brain size. Others have suggested that level of intelligence is due to the size of the frontal lobe. Now, however, a common view is that more subtle characteristics are likely to be involved, such as the speed at which nerve impulses travel in the brain, or the number of neuronal connections present. This study challenges that idea, suggesting that the volume of certain brain regions may have an effect after all. Richard Haier from the University of California, Irvine, and colleagues used magnetic resonance imaging to measure the amount of grey matter in the brains of 47 adults, who also took standard IQ tests. ©2004 Nature Publishing Group

Keyword: Intelligence
Link ID: 5860 - Posted: 06.24.2010

BY SANDRA GUY SUN-TIMES COLUMNIST Advertisement The brain's inner workings hold mysteries that Chicago area researchers love to try to solve. Researchers at Northwestern University have found a quirky new step toward understanding short-term memory -- the kind of memory that lets us remember a telephone number that we won't need to use again just long enough to dial it. The prefrontal cortex, a part of the brain that helps people plan and memorize, and control their emotions, also governs short-term memory. Researchers have long known that the many kinds of neurons in the cortex can work together to create specific patterns of excitation that carry meaning and information. The Northwestern researchers built a rough model of how this ensemble of neurons might work together. They assumed that the neurons are interconnected through a network that operates like a small world, and they saw a wave of activity that kept going around the intricate paths inside the network. Such a small-world network operates like a tourist trying to get around in New York City. Researchers previously thought the visitor could do one of two things: either walk block by block in a long and tedious journey, or spend all the time using the shortcuts provided by the subway. Copyright 2004, Digital Chicago Inc.

Keyword: Learning & Memory
Link ID: 5859 - Posted: 07.22.2004

Researchers have now found that amphetamines diminish people's anticipation of rewards. Scans of subjects' brains when they were led to anticipate a cash reward--as well as psychological self-assessments--revealed them to be less positively aroused by such anticipation under the influence of dextroamphetamine. Amphetamines are popularly known as "go pills" among fighter pilots, who take them to reduce fatigue on long flights. What's more, the researchers also found that the subjects who took the amphetamine were not as negatively aroused when they anticipated losses, which led the scientist to theorize that such drugs might help "maintain motivation, even in the face of adversity." Brian Knutson, assistant professor of psychology and neuroscience at Stanford University, and his colleagues reported experiments in which they asked eight volunteers to perform a task in which they had to respond to shapes on a screen in return for anticipated cash rewards. The researchers gave the subjects doses of either dextroamphetamine or a placebo.

Keyword: Drug Abuse
Link ID: 5858 - Posted: 07.22.2004

COLUMBUS, Ohio – Believe it or not, a 5-year-old could beat most adults on a recognition memory test, at least under specific conditions, according to a new study. These findings run counter to what has been known for years from memory research – namely, that memory develops from early childhood to young adulthood, with young adults having much better memory than children. In one study, children were accurate 31 percent of the time in identifying pictures of animals they had seen earlier, while adults were accurate only 7 percent of the time. And the memory difference was not because adults already have their mind filled with appointments, to-do lists and other various grown-up issues. The memory accuracy of adults is hurt by the fact that they know more than children and tend to apply this knowledge when learning new information, the findings showed. “It’s one case where knowledge can actually decrease memory accuracy,” said Vladimir Sloutsky, co-author of the study and professor and director of the Center for Cognitive Science at Ohio State University.

Keyword: Learning & Memory; Development of the Brain
Link ID: 5857 - Posted: 06.24.2010

As dusk settles across the Belfast skyline, Joe Neeson whistles and calls down his racing pigeons. Joe doesn't count - he doesn't need to. After years looking after his tiny loft in the yard behind his west Belfast home, he knows every bird by name. So when Joe scanned the roof above the loft on the day of Linda's first race, he knew there was a bird missing. The young pigeon had been released more than 300 miles away in Penzance. And as darkness fell, Joe knew that Linda was not coming home. Seven hundred miles away across the North Sea, Linda was beginning what would be a year-long adventure. No-one knows for sure how Linda arrived at the petrol refinery at Mongstad - one of Europe's biggest ports. It seems likely though that the exhausted pigeon "jumped ship" in the fading light as she flew across the North Sea. Refinery workers found her cowering under clothes lockers and took pity on the bird which seemed close to death. A Norwegian television crew was at the refinery to record a wildlife film, and journalist Hans Gunnar Skarstein realised that the band on the pigeon's leg held the key to her identity. (C)BBC

Keyword: Animal Migration
Link ID: 5856 - Posted: 07.21.2004

Most Alzheimer’s drugs treat the symptoms of dementia. But, as this ScienCentral News video reports, a new tool may soon predict who will develop the disease even before symptoms occur. Like it or not, our brains start shrinking at around age 40. But an accelerated type of brain shrinkage occurs in people who go on to develop Alzheimer's disease or other types of dementia. Now, research is revealing that the rate of brain volume loss may help identify those with mild cognitive impairment who are at risk for developing dementia. "Mild cognitive impairment refers to people who are in a transition stage between normal cognition and being demented," explains Deniz Erten-Lyons, a neurologist at Oregon Health and Science University. "They have memory complaints, but these are not severe enough for clinicians to make a diagnosis of dementia. Dementia is a general word for people with problems in brain functions—memory problems, language problems—to a degree that it affects their ability to function in their day to day living." Erten-Lyons says magnetic resonance imaging (MRI) brain scans may predict who will progress from mild cognitive impairment to full-fledged dementia. Her lab compared the scans of 55 volunteers over the span of 14 years; none of the subjects suffered from mild cognitive impairment at the beginning of the study. Each person was examined twice a year, given tests to place them into three categories: intact cognition, mild cognitive impairment that was considered stable, and mild cognitive impairment that progressed into Alzheimer's disease. © ScienCentral, 2000- 2004.

Keyword: Alzheimers
Link ID: 5855 - Posted: 06.24.2010

Chimpanzees yawn in response to seeing other chimps yawn, reveals a new study. The discovery bolsters the idea that chimps are able to understand their own and others' state of mind. Catching a glimpse of a colleague yawning during an important meeting is enough to have most humans fighting to stifle a gape. And the impression that yawning is "contagious" has stood up to scientific scrutiny. When adult humans are shown videos of yawns, around 42 to 55 per cent also begin yawning. Why humans do it is still controversial, although one suggestion is that it may have evolved as a social cue to synchronise sleep amongst a group. Now a research team led by James Anderson at the University of Stirling in the UK has shown that chimpanzees also perform "contagious yawning". © Copyright Reed Business Information Ltd.

Keyword: Emotions; Sleep
Link ID: 5854 - Posted: 06.24.2010

Peter Aldhous British animal-rights protesters have won another victory, now that the lead contractor building a research facility at the University of Oxford has withdrawn from the project. The protesters' opponents condemn the campaign of intimidation that led to the contractor's move. But they argue that it represents a minor hiccup, rather than a signal that the protesters are winning their war to end experimentation on animals. Oxford officials say that the US$33.5-million facility, due to open next year, is vital to the future of research at the university. Most of the planned research would be on rodents, investigating conditions including cancer, heart disease and stroke. Some monkeys would also be used. The lab became the main focus for the attention of British animal rights activists after the University of Cambridge abandoned plans to build a primate research facility in January this year. That decision was in part due to the soaring costs of providing security in the face of repeated protests. Repeating the tactics employed in previous campaigns, protesters soon began targeting contractors building the Oxford lab. The offices of a company providing concrete were heavily vandalized. Activists also sent letters to the shareholders of the lead contractor, a company called Montpellier, purporting to be from its chairman. These urged shareholders to sell their stock to avoid reprisals from the animal rights movement. ©2004 Nature Publishing Group

Keyword: Animal Rights
Link ID: 5853 - Posted: 06.24.2010

CHICAGO – The risk of suicidal behavior is increased in the first month after starting antidepressants, and is similar among users of four antidepressant drugs, according to a study in the July 21 issue of The Journal of the American Medical Association (JAMA). According to background information in the article, considerable public attention recently has focused on the relation between use of antidepressants, especially selective serotonin reuptake inhibitors (SSRIs), and suicidal ideation (having thoughts of suicide or of taking action to end one's own life) and suicidal behaviors. SSRIs are antidepressant drugs that work by making available more serotonin, a chemical in the brain that is thought to play a key role in depression and anxiety. The use of antidepressant drugs among teenagers has been of particular concern. Hershel Jick, M.D., and colleagues with the Boston Collaborative Drug Surveillance Program, Boston University, estimated the relative risks of non-fatal suicidal behavior in patients in the United Kingdom starting treatment with the SSRIs fluoxetine and paroxetine and another antidepressant, amitriptyline--compared with patients starting treatment with a fourth drug, dothiepin, that is not available in the U.S. Amtriptyline and dothiepin belong to a class of drugs known as tricyclic antidepressants. Participants could have used only one of the antidepressants, and had to have received at least one prescription for the drug within 90 days before their index date (the date of suicidal behavior or ideation for cases, and the same date for matched controls).

Keyword: Depression
Link ID: 5852 - Posted: 06.24.2010

ATLANTA- Emory University scientists are using a combination of transgenic mouse models and viral vectors to clarify the role of a brain molecule called LR11 in Alzheimer's disease (AD). LR11 is a receptor for apoliporotein E, which is involved in cholesterol metabolism and has previously been linked to AD. Early studies suggest that LR11 regulates levels of beta amyloid, which is the primary protein comprising the senile plaques in the brains of Alzheimer's patients. Sara E. Dodson, BS, a neuroscience program graduate student in Emory University's Division of Biological and Biomedical Sciences, will present results of her team's research at the 9th International Conference of Alzheimer's Disease and Related Disorders in Philadelphia on July 20 at 12:30 pm. The Emory scientists already have used human brain tissue to show that LR11 is markedly reduced in patients with Alzheimer's disease. In their current experiments, they combined special viruses, called lentiviruses, to selectively reduce and enhance LR11 expression in mouse brains and cultured cells to study the function of LR11. Lentiviruses are special in their ability to infect neurons and permanently alter expression of certain genes by the infected cells. The Emory scientists successfully used these viruses to deliver artificial genes into neurons to control expression of LR11 in mouse brains. When this approach was used in cultured cells to reduce LR11 levels and mimic the situation in Alzheimer's brains, there was a marked increase in beta amyloid, suggesting that LR11 plays a key role in regulating levels of this important molecule.

Keyword: Alzheimers
Link ID: 5851 - Posted: 07.21.2004

By SANDRA BLAKESLEE People who do not want to wait for old age to shrink their brains and bring on memory loss now have a quicker alternative - abuse methamphetamine for a decade or so and watch the brain cells vanish into the night. The first high-resolution M.R.I. study of methamphetamine addicts shows "a forest fire of brain damage," said Dr. Paul Thompson, an expert on brain mapping at the University of California, Los Angeles. "We expected some brain changes but didn't expect so much tissue to be destroyed." The image, published in the June 30 issue of The Journal of Neuroscience, shows the brain's surface and deeper limbic system. Red areas show the greatest tissue loss. The limbic region, involved in drug craving, reward, mood and emotion, lost 11 percent of its tissue. "The cells are dead and gone," Dr. Thompson said. Addicts were depressed, anxious and unable to concentrate. The brain's center for making new memories, the hippocampus, lost 8 percent of its tissue, comparable to the brain deficits in early Alzheimer's. The methamphetamine addicts fared significantly worse on memory tests than healthy people the same age. Copyright 2004 The New York Times Company

Keyword: Drug Abuse; Brain imaging
Link ID: 5850 - Posted: 07.20.2004

Rebecca Abrams applauds Sue Gerhardt's clear-sighted assessment of child development in Why Love Matters When researchers studied the brains of Romanian orphans - children who had been left to cry in their cots from birth and denied any chance of forming close bonds with an adult - they found a "virtual black hole" where the orbitofrontal cortex should have been. This is the part of the brain that enables us to manage our emotions, to relate sensitively to other people, to experience pleasure and to appreciate beauty. These children's earliest experiences had greatly diminished their capacity ever to be fully human. Sue Gerhardt's book Why Love Matters shows that early experience has effects on the development of both brain and personality that none of us can afford to ignore. It was Margaret Ainsworth, a Canadian psychologist, who first demonstrated a robust connection between early childhood experience and personality. For a large part of the 1960s Ainsworth sat behind a two-way mirror in Baltimore and watched one-year-olds playing with their mothers. She noted what happened when the mother left the room for a few minutes and how the child responded when she returned. She then took the study a stage further and studied what happened when, instead of the mother, a stranger entered the room and tried to engage with the child. Ainsworth's "Strange Situation" study, together with John Bowlby's attachment theory, showed that how a child developed was not the result of a general mish-mash of experiences, but the direct result of the way the child's main carer responded to and engaged with him or her. A neglectful, stressed or inconsistent parent gave the kind of care which tended to lead to anxious, insecure or avoidant children. Further studies showed that patterns of attachment behaviour in one-year-olds could accurately predict how those children would behave aged five and eight. © Guardian Newspapers Limited 2004

Keyword: Development of the Brain; Emotions
Link ID: 5849 - Posted: 06.24.2010

Nearly 3,000 babies a year die suddenly in their sleep in the U.S., leaving devastated parents wondering what went wrong. Findings published online this week in the Proceedings of the National Academy of Sciences offer insight into the genetic basis of one type of sudden infant death syndrome (SIDS). “This is one of the first genetic sub-classifications of SIDS,” says study leader Dietrich A. Stephan of the Translational Genomics Research Institute (TGen) in Phoenix, Ariz. “And it's going to be helpful in offering parents answers for sudden infant deaths, recognizing predisposition early, and hopefully saving a number of these babies.” The researchers identified children who suffered from a specific form of SIDS known as SIDDT in an Amish community in Pennsylvania. Twenty-one infants from nine families had passed away before the age of one and the scientists analyzed DNA from four of the babies as well as their parents, siblings and close relatives. The researchers identified an alteration in a gene on chromosome 6 called TSPYL: all four children had two abnormal copies of the gene and their parents each carried one copy of the alteration. TSPYL is expressed in the brainstem and sudden deaths may occur because of changes to the brain's regulatory systems that govern cardiac and pulmonary protective reflexes, the team reports. The researchers will next investigate the relationship between TSPYL mutations and SIDS in the general population, as well as the gene's role in controlling breathing and heart rate in premature infants that are otherwise normal. --Sarah Graham © 1996-2004 Scientific American, Inc.

Keyword: Sleep
Link ID: 5848 - Posted: 06.24.2010

MINNEAPOLIS / ST. PAUL—That cardinal singing his heart out in your backyard has ancestors that left the neighborhood of Australia 45 million years ago. A comprehensive study of DNA from songbirds and their relatives shows that these birds, which account for almost half of all bird species, did not originate in Eurasia, as previously thought. Instead, their ancestors escaped from a relatively small area--Australasia (Australia, New Zealand and nearby islands) and New Guinea--about 45 million years ago and went on to populate every other continent save Antarctica. The study, led by Keith Barker of the University of Minnesota's Bell Museum of Natural History, will be published online this week in the journal Proceedings of the National Academy of Sciences. The birds in question belong to the group called Passeriformes, or perching birds. It includes all songbirds, such as robins, cardinals, blackbirds, house sparrows, house finches and crows. The group is further divided into birds that must learn their songs "true songbirds") and those with the innate ability to sing the "correct" song. True songbirds account for 4,580 of the 6,000 known Passeriformes species. (There is a total of 9,702 known species of birds.) The true songbirds are currently divided into two groups: Passerida (3,477 species, among them many familiar backyard species) and Corvida (1,103 species, including crows and ravens). The two groups of true songbirds were thought to have separate origins. The Corvida originated in Australasia, but the Passerida were thought to have arisen separately, in Eurasia. The Passerida then supposedly spread from Eurasia to Africa, Australasia and the New World. But in examining the DNA sequences of two genes in all but one family (a closely related group, such as "crows and jays" or "warblers") of passerine birds, Barker and his colleagues made a startling discovery.

Keyword: Evolution
Link ID: 5847 - Posted: 06.24.2010

For some mice, getting drunk is a lot harder than chugging a few tequila shots. Mice that lack a particular protein receptor take longer than their alcohol-swilling peers to become intoxicated. The results provide a candidate gene for alcoholism and reveal a potential mechanism for how ethanol inebriates animals. No one knows why some people get giddy on a couple drinks while others stay sober, but those who require more libation to start dancing on tables have a higher risk of alcoholism. Alcohol boosts the amount of a brain chemical called adenosine--thought to cause the symptoms of drunkenness, including sedation--which limits the amount of alcohol one can imbibe. Booze increases adenosine by blocking a different protein receptor called ENT1, which normally transports loose adenosine back into the neuron. That means adenosine is free to whip up the woozy adenosine receptors. Chronic exposure to ethanol causes ENT1 receptors to become insensitive to alcohol and go back to cleaning up adenosine. Neurologist Robert Messing and colleagues at the Ernest Gallo Clinic and Research Center, Emeryville, California, wondered if lack of ENT1 from the get-go would make animals more tolerant to alcohol. To find out, they genetically engineered mice to lack both copies of the gene for ENT1. The team then tested their sensitivity to alcohol by injecting the mice with enough alcohol to get them just over the legal limit. Instead of putting them in driver's seat, the researchers placed the animals on a rotating rod to check their balance. Like talented midwestern log-rollers, the mice lacking ENT1 stayed on the rod nearly twice as long as the normal mice. Both types of animals had equivalent blood alcohol levels, indicating the effect was not due to faster metabolism of the ethanol by the mutants, the team reported 18 July online in Nature Neuroscience. Copyright © 2004 by the American Association for the Advancement of Science.

Keyword: Drug Abuse
Link ID: 5846 - Posted: 06.24.2010