COLLEGE STATION, - A baby's understanding of language may begin with its own name, which a baby uses to break sentences into smaller parts so it can learn other words, according to new research by Texas A&M University psychologist Heather Bortfeld, who studies language development in infants and children. Bortfeld's research, which appears in the upcoming April issue of "Psychological Science," shows that babies use familiar words such as their names as a sort of "anchor" into the speech stream. A baby as young as six months can learn to recognize an individual word that follows its own name, even after hearing both words as part of whole sentences, says Bortfeld who worked with colleagues from Brown University and the University of Delaware. "Recognition drives segmentation of the speech stream, and segmentation is a critical step in learning a language," Bortfeld explains. "We know from previous research that babies are recognizing their names in fluent speech by the age of six months, so we hypothesized that they should be able to use that recognition to segment the speech stream and recognize new words." Much in the same way a person might have difficulty understanding a foreign language because it's hard to tell where one word starts and another begins, babies face a similar challenge in learning language. Bortfeld's research shows babies can begin to discern the beginnings and endings of words that follow their names, meaning their names form a foundation for learning language.

Keyword: Language
Link ID: 7169 - Posted: 04.12.2005

Women who smoke when pregnant may spark asthma in their grandchildren decades later, a new study discovers. A child whose maternal grandmother smoked while pregnant may have double the risk of developing childhood asthma compared with those with grandmothers who never smoked, say researchers from the University of Southern California, US. And the risk remains high even if the child’s mother never smoked. It has been known for some time that smoking while pregnant can increase the risk of the child developing asthma, but this is the first time that the toxic effects of cigarette smoke have been shown to damage the health of later generations. The researchers believe that the tobacco may be altering which genes are switched “on” or “off” in the fetus’s reproductive cells, causing changes that are passed on to future generations. Frank Gilliland, professor of preventative medicine at the Keck School of Medicine in Los Angeles, US, and colleagues interviewed the parents of 338 children who had asthma by the age of five and a control group of 570 asthma-free children. They found that children whose mothers smoked while pregnant were 1.5 times more likely to develop asthma that those born to non-smoking mothers. © Copyright Reed Business Information Ltd.

Keyword: Drug Abuse; Development of the Brain
Link ID: 7168 - Posted: 06.24.2010

Butterflies do not flutter aimlessly around the garden but instead follow precise flightpaths, scientists say. A UK team of researchers made the discovery by tracking the insects with radar, using tiny transponders attached to the backs of butterflies. This gave them information on the insects' flightpaths, speeds and foraging behaviour - some of which could guide conservation measures. Details of the research appear in Proceedings of the Royal Society B. "We've never been able to see their flight tracks up to 1km before and it's showing us that they do seem to be quite directive in the way they're flying," said co-author Lizzie Cant of Rothamsted Research in Harpenden, UK. The scientists tagged peacock (Inachis io) and small tortoiseshell (Aglais urticae) butterflies with transponders weighing just 12mg. After checking that the devices did not affect their behaviour, the researchers released 33 insects into a 500x400 sq m field being scanned by radar on the Rothamsted estate. This allowed them to track an individual butterfly at a range of up to about 1km. They successfully recorded the movements of 30 of the insects they released. (C)BBC

Keyword: Animal Migration
Link ID: 7167 - Posted: 04.10.2005

COLUMBUS, Ohio – A gene that is changed in many forms of cancer has also been found to show similar changes in some forms of autism, according to preliminary research. The gene, known as PTEN, was found to be changed, or mutated, in three of 18 people with larger than normal heads and autism spectrum disorder. Autism spectrum disorder includes classical autism, Rett syndrome and other conditions. The study was led by researchers at The Ohio State University Comprehensive Cancer Center – Arthur G. James Cancer Hospital (OSU CCC-James) and Richard J. Solove Research Institute and at Children’s Mercy Hospitals and Clinics, Kansas City, Mo. Inherited gene mutations in the PTEN gene are seen in Cowden syndrome, a poorly recognized disorder that increases a person’s risk of developing cancers of the breast, thyroid and uterus. PTEN mutations are also found in several non-inherited (i.e., spontaneous) cancers, including thyroid and endometrial cancers and some brain tumors. The findings, published in the April Journal of Medical Genetics, raise the possibility that some people with autism and large heads may have an increased risk of cancer. “If our findings are verified, I think that patients with classical autism or autism spectrum disorders and who have large heads should be offered genetic counseling and testing for PTEN mutations,” says principal investigator Charis Eng, professor of internal medicine and director of the clinical cancer genetics program at the OSU CCC-James.

Keyword: Autism; Genes & Behavior
Link ID: 7166 - Posted: 06.24.2010

If you've ever stepped out on a 10-meter-high diving platform or wandered down a dark alley, you're probably familiar with the racing heart and sweaty palms that characterize the autonomic nervous system's response to fear. Now, researchers have clarified the molecular underpinning of the brain’s fear response. The findings may point the way to better drugs for people with phobias and other anxiety disorders. Fear responses are controlled by an almond-shaped structure called the amygdala, located deep inside the brain. The amygdala weighs messages sent from many regions of the brain, and when things get sufficiently scary, it triggers the autonomic fear response via "output" neurons located in a subdivision called the central amygdala. In the new study, neuroscientist Daniel Huber at the University of Lausanne, Switzerland, and colleagues used slices of rat brains to take a closer look at the chemical communication signals used by the central amygdala's neurons. They found that vasopressin, a peptide known to boost anxiety and stress, increased the electrical activity of output neurons in one part of the central amygdala, while oxytocin, a peptide with nearly opposite effects on mood, stimulated neurons in an adjacent region. Moreover, neurons stimulated by oxytocin released a neurotransmitter that inhibited the vasopressin-sensitive output neurons. The findings suggest that vasopressin and oxytocin have contrasting influences on behavior because they have opposite effects on the output neurons of the central amygdala, the team reports in the 8 April issue of Science. The researchers speculate that natural variations in the balance of vasopressin and oxytocin receptors in the central amygdala could explain why some individuals are typically nervous, while others are seemingly immune to anxiety. Copyright © 2005 by the American Association for the Advancement of Science.

Keyword: Emotions; Hormones & Behavior
Link ID: 7165 - Posted: 06.24.2010

New Haven, Conn.-Long-acting injections of the drug naltrexone, combined with psychotherapy, significantly reduced heavy drinking in patients being treated for alcohol dependence, according to a study in the Journal of the American Medical Association by a Yale School of Medicine researcher. "The decision to take medication can wane over time," said Stephanie O'Malley, professor of psychiatry and director of the Division of Substance Abuse Research at the Connecticut Mental Health Center at Yale. "This provides coverage for an entire month." Acohol dependence ranks as the fourth leading cause of disability worldwide, as reported by the World Health Organization's Global Burden of Disease project. Nationwide, it is believed to contribute to more than 100,000 preventable deaths a year. Naltrexone belongs to a class of drugs called opioid antagonists. Although many clinical trials have shown that oral naltrexone can be effective in treating alcohol dependence, its use in clinical practice has been limited, in part patients have to take the pill daily.

Keyword: Drug Abuse
Link ID: 7164 - Posted: 04.10.2005

PORTLAND, Ore. -- An Oregon Health & Science University researcher is among an international team closing in on why many people with schizophrenia and other psychotic disorders are "supersensitive" to the powerful neurotransmitter dopamine. David Grandy, Ph.D., associate professor of physiology and pharmacology, OHSU School of Medicine, co-authored a study appearing recently in Proceedings of the National Academy of Sciences that found a link between dopamine supersensitivity and increased levels of a dopamine receptor with a particularly high affinity for dopamine. Dopamine is a neurotransmitter found in the brain that plays an important role in the regulation of behavior involved in movement control, motivation and reward, and the dopamine system is thought to be essential to the brain's response to drugs of abuse, especially opiates and psychostimulants. Supersensitivity to dopamine, which affects some 70 percent of individuals with schizophrenia, can take the form of a low tolerance to antipsychotics, amphetamines and other drugs, including drugs of abuse, that trigger dopamine's release in the brain. The latest discovery could someday lead to the development of drug therapies that temporarily bring people with psychosis into a more normal, less-sensitive state and make them more amenable to antipsychotic treatment.

Keyword: Schizophrenia; Genes & Behavior
Link ID: 7163 - Posted: 04.10.2005

Christen Brownlee Historian Frank W. Sweet of the University of Florida in Gainesville recounts the classic rags-to-riches tale of Louetta Chassereau, an early 20th-century socialite. As a baby, Chassereau was adopted from an orphanage by a well-to-do white couple. She later married a wealthy man, and her children attended the best white-only schools. However, a dilemma developed when Chassereau's husband died, leaving everything in his will to his beloved wife. Enraged, her husband's relatives contested the will. The reason? Although people in her community had always thought of her as white, "Louetta had started life as a Black baby," says Sweet in a recent essay. Because Chassereau was born of black parents, according to an antimiscegenation law of the time, Chassereau legally could marry only a black man. The white family claimed that she had no right to the fortune. Although the courts ruled in Chassereau's favor in 1940, saying that her life's path had made her "irrevocably white," her in-laws remained unconvinced. In the past 65 years, defining race hasn't become less ambiguous. While it's abundantly clear that race exists from a sociological standpoint—racism wouldn't take place without it—does that categorization also exist biologically? Current genetic research hasn't yet come up with a black-and-white answer. Nevertheless, understanding the biology underlying perceptions of race could have dramatic implications. Copyright ©2005 Science Service

Keyword: Genes & Behavior
Link ID: 7162 - Posted: 06.24.2010

Bruce Bower Two new lines of evidence bolster the claim that the oldest known member of the human-evolutionary family lived in central Africa between 6 million and 7 million years ago. In 2001, at a site in Chad, anthropologist Michel Brunet of the University of Poitiers in France and his coworkers found jaw fragments, isolated teeth, and the nearly complete skull of a creature that the researchers identified as a hominid and assigned to the category Sahelanthropus tchadensis. The skull combines a cranium suitable for a chimp-size brain with facial and tooth structures resembling those of later human ancestors (SN: 7/13/02, p. 19: http://www.sciencenews.org/articles/20020713/fob1.asp). After the discovery, a group of researchers led by Milford H. Wolpoff of the University of Michigan in Ann Arbor initiated a controversy by contending that Sahelanthropus looks more like a fossil ape than a hominid (SN: 10/19/02, p. 253: Available to subscribers at http://www.sciencenews.org/articles/20021019/note12.asp). Brunet's team now reports the discovery of two more jaw pieces and another tooth from Sahelanthropus. The researchers unearthed the specimens in Chad at three locations, including the site of the prior finds. Copyright ©2005 Science Service.

Keyword: Evolution
Link ID: 7161 - Posted: 06.24.2010

Narelle Towie After months roaming the waves as larvae, it seems that fish tune into the sounds of home when they want to settle down. A study on Australia's Great Barrier Reef has shown that the crackle of shrimp and the calls of fellow fish serve to attract tropical tiddlers. Researchers working near Lizard Island, 240 kilometres north of Cairns, Queensland, set up 24 fake reefs made from dead coral. Half the reefs contained submersible speakers that played a cacophony of genuine reef noise consisting of snapping shrimp and other fish. They found that noisy reefs attracted a far greater number of fish than those that were silent. "We knew that they were attracted to light traps. But no one had shown that the fish located sound and could be encouraged to settle depending on it," says Stephen Simpson of the University of Edinburgh, UK, who led the research. Around 80% of the fish attracted to the reefs were cardinalfish (apogonids), and most of the remainder were damselfish (pomacentrids). But noisy reefs also attracted a wide range of less common fish, the researchers report in Science1. ©2005 Nature Publishing Group

Keyword: Hearing
Link ID: 7160 - Posted: 06.24.2010

Just think how eerie it would be, yet also how peaceful - people all around having conversations on their mobile phones, but without uttering a sound. Thanks to some military research, this social nirvana just might come true. DARPA, the US Department of Defense's research agency, is working on a project known as Advanced Speech Encoding, aimed at replacing microphones with non-acoustic sensors that detect speech via the speaker's nerve and muscle activity, rather than sound itself. One system, being developed for DARPA by Rick Brown of Worcester Polytechnic Institute in Massachusetts, relies on a sensor worn around the neck called a tuned electromagnetic resonator collar (TERC). Using sensing techniques developed for magnetic resonance imaging, the collar detects changes in capacitance caused by movement of the vocal cords, and is designed to allow speech to be heard above loud background noise. DARPA is also pursuing an approach first developed at NASA's Ames lab, which involves placing electrodes called electromyographic sensors on the neck, to detect changes in impedance during speech. A neural network processes the data and identifies the pattern of words. The sensor can even detect subvocal or silent speech. The speech pattern is sent to a computerised voice generator that recreates the speaker's words. © Copyright Reed Business Information Ltd

Keyword: Language
Link ID: 7159 - Posted: 06.24.2010

Drinking a glass or two of milk a day may raise the risk of Parkinson's disease in middle-aged men, research suggests. Researchers say the apparent link is unlikely to be anything to with calcium - milk's key nutritional ingredient. But they say it is unclear whether another ingredient, or a contaminant may raise the risk of Parkinson's - which overall still remains low. The study, led by Korea University, is published in the journal Neurology. Parkinson's disease is a degenerative disease of the nervous system associated with trembling of the arms and legs, stiffness and rigidity of the muscles and slowness of movement. Previous research has also suggested a link between high consumption of dairy products and a raised risk of Parkinson's in men - but not women. The latest study focused on 7,504 men aged 45 to 68, who were enrolled in a heart study in Hawaii. During the course of the 30-year study, 128 developed Parkinson's. The researchers found those men who consumed more than 16oz (454g) of milk a day were 2.3 times more likely to develop Parkinson's than those who drank no milk at all. Overall, the risk of Parkinson's - even among men who drank a lot of milk - was low. The researchers calculated that in each 12 month period 6.9 cases of Parkinson's could be expected per 10,000 people who drank no milk. Among those who drank more than 16ozs a day the figure was 14.9 per 10,000. However, they found no evidence of a link between calcium consumption and Parkinson's. (C)BBC

Keyword: Parkinsons
Link ID: 7158 - Posted: 04.07.2005

New Haven, Conn.--Sensory deprivation causes changes in new cell size and excitability in the olfactory system, which governs the ability to smell, according to a study in Neuron by a Yale School of Medicine researcher. "This gives new insight into how stem cells in the olfactory system may be used to restore function in a brain that has been compromised by degenerative disease or trauma," said Gordon Shepherd, M.D., co-author of the paper and professor of neuroscience at Yale. Shepherd, on sabbatical with Pierre-Marie Lledo of the Pasteur Institute, investigated how the olfactory system responds to changes brought about by injury or different levels of activity. They closed one nostril in mice, a common sensory deprivation procedure, and then observed how the olfactory system adjusted to the change in sensory input. The olfactory system is one of the most plastic regions of the brain, with nerve cells that are continually replenished by stem cells. Stem cells in the nose replenish the sensory cells, which send the odor messages to the olfactory bulb. "There also are stem cells deep in the brain that replenish the interneurons, which carry out much of the processing of the odor messages that takes place in the olfactory bulb," Shepherd said.

Keyword: Chemical Senses (Smell & Taste)
Link ID: 7157 - Posted: 04.07.2005

Researchers studying yeast cells have identified a metabolic enzyme as a potential therapeutic target for treating Huntington's disease, a fatal inherited neurodegenerative disorder for which there is currently no effective treatment. The group, whose results appear in the May issue of Nature Genetics, includes researchers from the University of Washington School of Medicine in Seattle and the University of Maryland School of Medicine in Baltimore. The paper was published online in advance at the journal's Web site, http://www.nature.com/ng/index.html. The group performed a genetic experiment known as a loss-of-function suppressor screen, which searches for genes that, when switched off, reduce the toxic effects of the mutant protein associated with Huntington's. One of the genes they identified encodes an enzyme, called KMO, that has been previously implicated in the disease. The enzyme functions in a metabolic pathway that is activated at early stages of the disease in people with Huntington's, as well as in animal models of the disease. "The nice thing about this finding is that there is a chemical compound available that inhibits KMO activity," said Dr. Paul Muchowski, assistant professor of pharmacology at the UW, who led the study. "We're in the midst of testing that compound in a mouse model of Huntington's disease." © 2005 University of Washington Office of News and Information

Keyword: Huntingtons
Link ID: 7156 - Posted: 06.24.2010

Long ago it may have been a lot easier for people to pass up extra food they didn't need sweet and salty foods like chips and cookies that so many of us crave. Scientists at the University of California, Davis have described for the first time how a protective brain mechanism, evolved long ago, makes sure animals eat a balanced diet of amino acids, the building blocks of protein, while turning from away foods they don't need. It's an ability that people may have once had, but is now lost to modern temptations. Getting enough amino acids is a priority for the body because they're essential to protein synthesis - the process that powers all the work our bodies do, like maintaining muscle tone, and repairing cuts - basically keeping us healthy. "If we don't have them in the diet or in our food the way we should," says lead researcher and professor of veterinary medicine Dorothy Giezten, "then we have to start breaking down our own body proteins." Scientists have known for decades that if an animal is deficient in any of the eight amino acids it needs to survive, it will reject foods that also lack those amino acids and search for other food. But until now, they never understood what controlled this choosy behavior. The researchers reported in the journal Science how a series of biochemical reactions runs this behavior in rats and mice. They say the reactions are identical to those seen in yeast, one of the world's simplest organisms, as well as in pigs, birds, and cats. Because so many different organisms share this mechanism, Giezten says it is second only to that which drives animals to eat when they are hungry. "It's so fundamental that it's conserved across all, what we call eukaryotic species, from all the way across evolution - from the simplest single cell organisms [like yeast], all the way up to people," says Gietzen. (C) ScienCentral, 2000-2005.

Keyword: Obesity
Link ID: 7155 - Posted: 04.07.2005

Genetic paternity tests have revealed that many apparently monogamous species indulge in infidelity, but scientists have puzzled over the benefits of these illicit liaisons. New research shows that, in the Seychelles warbler, the benefits are likely linked to genes associated with immune function. The Seychelles warbler is a songbird that inhabits a few small islands in the Indian Ocean's Seychelles group. On Cousin Island, breeding territories are in short supply, and females can't be too fussy about whom they choose as mates. But many make up for this lack of choice by having affairs: 40% of Cousin's warbler chicks are not fathered by their mother's mate. Reasoning that affairs might be a way for females to improve the genetic quality of their offspring, molecular ecologist David Richardson, of the University of East Anglia in Norwich, U.K., and colleagues investigated the relationship between female mate choice and the diversity of each individual's Major Histocompatibility Complex (MHC) genes. The MHC is a group of molecules which plays a major role in the body's immune response to pathogens. Studies in some species have shown that individuals with higher MHC diversity are better able to resist pathogens. The team found that there was indeed a relationship between MHC diversity and infidelity: Female warblers cheated far more frequently on males with below-average MHC diversity than on males with higher MHC diversity. Richardson says that the females don't appear to "sniff out" MHC characteristics the way mice do, so it may be that MHC diversity is associated with other features, such as superior singing or fighting, which make males more attractive or allow them to outcompete others. The team reports its findings in this week's online edition of Proceedings of the Royal Society B. Copyright © 2005 by the American Association for the Advancement of Science.

Keyword: Sexual Behavior; Evolution
Link ID: 7154 - Posted: 06.24.2010

Despite the divergent evolutionary paths of dolphins and primates -- and their vastly different brains -- both have developed similar high-level cognitive abilities, says Emory University neuroscientist and behavioral biologist Lori Marino. She presented her latest findings on the evolution of and differences in brain structure between cetaceans (ocean mammals like whales and dolphins) and primates April 5 during the 14th annual Experimental Biology 2005 meeting in San Diego. Marino's presentation examined the diverse evolutionary patterns through which dolphins and primates acquired their large brains, how those brains differ, and how sensory information can be processed in different ways and still result in the same cognitive abilities. "Eventually, a better understanding of how other species process information might be useful in helping people impaired in "human" ways of processing information. Perhaps there are alternative ways to sort out information in our own brains," says Marino, whose talk was part of the scientific sessions of the American Association of Anatomists.

Keyword: Evolution
Link ID: 7153 - Posted: 04.07.2005

A drug prescribed for the prevention of osteoporosis reduced women's risk of mild cognitive impairment by 33 percent in a worldwide clinical trial led by researchers at San Francisco VA Medical Center (SFVAMC). The drug, raloxifene, modulates the activity of the hormone estrogen. The finding was published in the April 2005 issue of the American Journal of Psychiatry. Mild cognitive impairment (MCI) affects more than one-third of women and one-fifth of men aged 65 and older. It reduces short-term memory and is associated with a significantly increased risk of Alzheimer's disease. "No other intervention has been proven to reduce the risk of mild cognitive impairment," says Kristine Yaffe, MD, the principal investigator of the trial. Yaffe is UCSF associate professor of psychiatry, neurology and epidemiology and chief of geriatric psychiatry at SFVAMC. Raloxifene is one of the most broadly prescribed drugs for the treatment of osteoporosis (it is also used to treat breast cancer). It is manufactured by Eli Lilly, which sponsored the trial, called the Multiple Outcomes of Raloxifene Evaluation (MORE). In the MORE trial, which took place at 180 clinical sites in 25 countries, 7,705 postmenopausal women with osteoporosis were randomly assigned to take a daily dose of either 120 milligrams of raloxifene, 60 milligrams of raloxifene, or a placebo for three years. Participants at 161 sites -- 7,023 women -- were measured for cognitive impairment at the beginning of the study and every year thereafter; cognitively impaired women were kept in the study.

Keyword: Alzheimers; Hormones & Behavior
Link ID: 7152 - Posted: 04.07.2005

HOUSTON -- – A study at Baylor College of Medicine in Houston may lead to a better understanding of how antidepressants like Prozac work – and how to make them more effective. According to results published in today's issue of the journal Neuron, a study in mice proposes that dopamine and serotonin neurotransmitter systems in the brain occasionally get their signals crossed, causing delays in stabilizing mood. "This study provides a new site for drug discovery in one of the biggest market for drugs – those that treat symptoms of depression," said Dr. John Dani, professor of neuroscience at BCM and lead author of the study. Dani's study, funded by the National Institutes of Health, offers an alternative explanation for the delayed effect of most antidepressants. "Some scientists thought that you had to take an antidepressant for weeks because as serotonin is elevated, some of its receptors had to turn off and become desensitized rather than be stimulated," Dani said. "That didn't make a lot of sense to us since desensitization is usually a rapid mechanism." Serotonin and dopamine neurotransmitter systems, which factor heavily in regulating mood, emotional balance, and psychosis, are released and reabsorbed in the striatum, an area of the brain which affects motivation and reward-based learning. Dani's findings indicate that these systems may be less selective and more "promiscuous" than previously believed.

Keyword: Depression
Link ID: 7151 - Posted: 06.24.2010

— French-led fossil hunters have fired the latest salvo in a battle over Toumai, a seven-million-year-old fossil that, they contend, is the earliest human ever found. Toumai came to the fore in 2002 when a team led by Michel Brunet of the University of Poitiers, central France, unveiled a nearly complete cranium, pieces of jawbone and several teeth that had been found in the Chadian desert. Animal remains in the earth layers in which these pieces were found indicated the age at up to seven million years, making Toumai the earliest known hominid, or forerunner of Homo sapiens, ever discovered. But the claim triggered dismay in Ethiopia and Kenya — the countries of the Great Rift Valley where humankind is commonly believed to have emerged — as well as rebuttals from within the palaeontology community, which beneath its placid veneer can be viciously competitive. Critics said that Toumai's cranium was too squashed to be that of a hominid — it did not have the brain capacity that gives humans primacy — and its small size indicated a creature of no more than 120 centimetres (four feet) in height, about the size of a walking chimp. Copyright © 2005 Discovery Communications Inc.

Keyword: Evolution
Link ID: 7150 - Posted: 06.24.2010