A small fish with a remarkable hearing system that enables females to zero in on the love hums broadcast by males during the breeding season is providing scientists with clues that someday might provide a treatment for people with high-frequency hearing loss. Researchers from the University of Washington and Cornell University have duplicated a natural physiological change that occurs in the female plainfin midshipman fish (Porichthys notatus) during the breeding season. Working with non-reproductive females, the researchers boosted hormone levels that alter the fish's inner-ear hearing sensitivity for a short period so they can better hear the males' humming calls. "This is the first time anyone has been able to hormonally induce a change in hearing sensitivity in a vertebrate," said Joseph Sisneros, a UW assistant psychology professor who studies the neural basis of behavior. He is the lead author of a paper being published in the July 16 edition of the journal Science. Sisneros and a Cornell research team headed by Andrew Bass, found that a spike in levels of the hormones testosterone and estradiol (an estrogen) triggers changes in the females' inner ear so they are capable of detecting higher frequencies in the males' multi-harmonic humming. This process couples the transmission of sound by the males and reception by the females.

Keyword: Sexual Behavior; Hearing
Link ID: 5819 - Posted: 07.16.2004

The idea that a woman's emotional state during pregnancy affects her unborn child has persisted for centuries and has, in recent years, been supported by science. Called the "fetal programming hypothesis," it theorizes that certain disturbing factors occurring during certain sensitive periods of development in utero can "program" set points in a variety of biological systems in the unborn child. This, then, affects the ability of those biological systems to change later in life, resulting in difficulties adapting physiologically and ultimately predisposing a child to disease and disorder. We decided to investigate the affect of high levels of anxiety during a woman's pregnancy on her child's susceptibility for attention deficits, hyperactivity, acting out and anxiety disorders in childhood. We also wanted to learn whether there are specific vulnerable periods during the pregnancy in which this anxiety "programs" the child's biological system, thus increasing the fetus' susceptibility for such disorders. We evaluated data collected on 71 normal mothers and their 72 first-born children during pregnancy and when their children were 8 or 9. The mothers completed questionnaires to measure their anxiety levels throughout their pregnancy. When the children were 8 or 9, the mothers, a teacher, and an impartial observer completed questionnaires to measure the child's attention and hyperactivity, acting-out behavior and anxiety level.

Keyword: Development of the Brain; ADHD
Link ID: 5818 - Posted: 07.16.2004

Cysts in Rats Develop Two-Way Communication with Brain TALLAHASSEE, Fla.-Researchers know what causes endometriosis, but how the cysts that are characteristic of the disease maintain themselves and produce severe pain in some women has remained a mystery. New research led by Florida State University Professor of Neuroscience Karen Berkley indicates that endometrial cysts develop their own nerve supply that could contribute both to the pain symptoms and the body's ability to maintain the disease. "The new nerves likely sprout from those that supply the blood vessels that grow along with and nourish the cysts," Berkley said. "It has been well known that the cysts need a blood supply to survive. It also has been well known that blood vessels have their own nerve supply. Surprisingly, no one before us had put the two ideas together - that the cysts would be supplied by nerves that grow and extend from those that supply the cyst's blood vessels." Berkley and colleagues Natalia Dmitrieva and Kathleen Curtis, both of FSU, and Raymond Papka, of Northeastern Ohio Universities College of Medicine, drew the conclusion after studying rats with surgically induced endometriosis. Their findings will be published in the Proceedings of the National Academy of Sciences journal.

Keyword: Pain & Touch; Hormones & Behavior
Link ID: 5817 - Posted: 07.16.2004

The research does not reveal the cause of the anomalies. By Dorsey Griffith -- Bee Medical Writer A new study by the UC Davis MIND Institute has found that two areas in the brain are larger in boys with autism than in boys who are developing normally. The study, published in Wednesday's edition of the Journal of Neuroscience, represents the most comprehensive examination yet of brain volume in children with autism. The findings, which confirm some earlier studies, do not explore what caused the brain abnormalities or when the growth began to go awry but will better direct future autism research, said David Amaral, the study's principal investigator and research director at the MIND Institute. "It's beginning to point to the idea that in certain children with autism there is a defect that allows the brain to develop too quickly," he said. "This gives us a target to carry out fundamental neuroscience." Autistic people generally have difficulty speaking, relating to others and responding appropriately to their environment. The disorder typically is diagnosed in early childhood; some parents report their children were developing normally before symptoms appeared. Copyright © The Sacramento Bee

Keyword: Autism
Link ID: 5816 - Posted: 06.24.2010

St. Paul, Minn. – People with vertigo can get relief by doing maneuvers at home, according to a study published in the July 13 issue of Neurology, the scientific journal of the American Academy of Neurology. The study involved people with benign paroxysmal positional vertigo, an inner ear problem that causes a feeling of spinning or whirling when you move your head into certain positions. The vertigo usually lasts less than a minute. It can be mild or severe enough to cause nausea. It affects an estimated 64 people in every 100,000. This type of vertigo is believed to be caused by loose particles floating in the inner ear canal, which maintains the body’s equilibrium. Certain head and body movements can clear the particles from the ear canal. In general, the maneuvers are performed by a doctor or therapist. “For most people, one treatment is all it takes to stop the vertigo,” said study author Andrea Radtke, MD, a neurologist with Charité Campus Virchow Clinic in Berlin, Germany. “But some people need repeated treatments before it resolves completely. For these people, it would be beneficial to have the option to treat themselves at home.”

Keyword: Miscellaneous
Link ID: 5815 - Posted: 06.24.2010

The air in the meeting room had grown stale as the afternoon wore on, but Minnesota Attorney General Mike Hatch listened intently, puzzling his way through the data. Leaning forward at the head of the oak table that dominated the room, he asked, "Are you saying there is still mercury in vaccines today?" After a quick glance at his attaché case, Dr. Mark Geier replied, "In several of them-we have the bottles here to show you." "I thought the Federal and Drug Administration required it to be removed," countered Hatch. Mark Geier sighed. "They recommended it be removed. Many of our children are still being injected with mercury at their well-baby checkups." Mercury is the main component of thimerosal, an antibacterial preservative that until recently was used in most vaccines. It has become a lightening rod in an escalating debate over the cause of the nation's rising rates of autism. It has entangled parents, health care providers, legislators, attorneys, public health officials, and drug makers, prompting them to ask one central question: Is thimerosal the mark of colossal government negligence or merely a symbol of parental desperation? © 2004 Seed Magazine.

Keyword: Autism; Neurotoxins
Link ID: 5814 - Posted: 06.24.2010

Any dog owner can tell you about the benefits of spending time with a furry friend. But now there's some science to back it up. "We have known for a long time that people like to interact with dogs and that it makes them feel happy and they enjoy it," says Rebecca Johnson, a gerontologist at University of Missouri-Columbia's Sinclair School of Nursing. "But it's important to know how this affects the changes in their bloodstream, so we can see which patients might be the best to benefit from this kind of interaction." In her on-going study, Johnson asks 50 dog owners and 50 non-pet owners, with ages ranging from 19 to 73, to play with a live dog and a robot dog. Before and after the interactions, she draws blood samples from human and dog, to compare hormone levels. "One of the hormones that we are interested in, which is called serotonin, is the hormone that controls depression in people," Johnson explains. Johnson's preliminary results show that serotonin increases when people pet their own dogs. "We think this is very important because of the large numbers of people in this country and abroad that are depressed, particularly the elderly, that we think may benefit from this kind of interaction," says Johnson. However, interaction with an unfamiliar dog didn't affect serotonin levels. © ScienCentral, 2000- 2004.

Keyword: Emotions
Link ID: 5813 - Posted: 06.24.2010

By studying fruit fly ovaries, Johns Hopkins scientists have discovered that a protein known to block cell death also has the completely independent role of enabling normal cell movement. The discovery creates an unexpected new path to follow in the effort to understand the biochemical steps behind cells' movement, a critical aspect of embryonic development and the spread of cancer. The work is described in the July 8 issue of Cell. By studying fruit flies engineered to make extra use of random genes, the Hopkins team discovered that a protein called "inhibitor of apoptosis-1" (or IAP) can restore the tightly choreographed cellular movement that naturally occurs in fruit fly ovaries as egg cells mature. "This discovery was completely unexpected," says Denise Montell, Ph.D., professor of biological chemistry in Johns Hopkins' Institute for Basic Biomedical Sciences. "Based on what was known about this protein's function in blocking cell death, there would have been no way to predict its involvement in cell migration."

Keyword: Development of the Brain; Apoptosis
Link ID: 5812 - Posted: 07.15.2004

Michael Hopkin It is no coincidence that so many piano-tuners are blind. Folklore says their lack of sight gives them acute hearing, ideally suited to the task. Now neuroscientists in Canada have shown that the sightless really do hear notes more precisely if they went blind when they were very young. The idea that blindness can aid musical development is an old one, says Robert Zatorre of McGill University in Montreal, a member of the study team. Ray Charles and Stevie Wonder, who both lost their sight at an early age, were among the twentieth century's most influential musicians. But previous attempts to quantify the effect have met with mixed results. Zatorre thinks this is because they did not take account of the age at which subjects went blind. The researchers therefore divided their 14 blind subjects into two groups: those who were blind at birth or lost their sight during the first two years of life, and those for whom blindness came later. The team also tested fully sighted people to see which of the three groups performed best at pitch-recognition tasks. ©2004 Nature Publishing Group |

Keyword: Hearing; Vision
Link ID: 5811 - Posted: 06.24.2010

BABIES exposed to sign language babble with their hands, even if they are not deaf. The finding supports the idea that human infants have an innate sensitivity to the rhythm of language and engage it however they can, the researchers who made the discovery claim. Everyone accepts that babies babble as a way to acquire language, but researchers are polarised about its role. One camp says that children learn to adjust the opening and closing of their mouths to make vowels and consonants by mimicking adults, but the sounds are initially without meaning. The other side argues that babbling is more than just random noise-making. Much of it, they contend, consists of phonetic-syllabic units - the rudimentary forms of language. Laura-Ann Petitto at Dartmouth College in Hanover, New Hampshire, a leader in this camp, has argued that deaf babies who are exposed to sign language learn to babble using their hands the way hearing babies do with their mouths. Petitto believes that the hand-babbling is functionally identical to verbal babbling- only the input is different. But critics counter that deaf children cannot be directly compared with their hearing counterparts. Now Petitto and her colleagues have tested three hearing babies who, because their parents are deaf, were exposed only to sign. Three control infants had hearing, speaking parents. To analyse the hand movements of the six children, the researchers placed infrared-emitting diodes on the babies' hands, forearms and feet.

Keyword: Language
Link ID: 5810 - Posted: 07.15.2004

PORTLAND, Ore. -- An Oregon Health & Science University research team has uncovered a novel form of transmission between neurons in the brain that is mediated by dopamine. The neurons are found in parts of the brain associated with movement, substance abuse and mental disorders. Scientists at the Vollum Institute, OHSU School of Medicine, reported in a study published in the journal Neuron that the neurotransmitter dopamine is released from midbrain nerve cells in a much more precise, targeted manner than previously thought. They discovered that dopamine molecules are released as packages from stores, or vesicles, in branch-like extensions of neurons called dendrites. The dopamine travels to dopamine receptors on tiny terminals within milliseconds. Until now, scientists had only detected the release of dopamine in the midbrain and suspected that the neurotransmitter was dispersed over wide areas to reach receptors. "We've demonstrated that this synaptic current is over and done within a second," said John Williams, Ph.D., senior scientist at the Vollum Institute, OHSU School of Medicine, and a study co-author. "We knew dopamine was released in this place, we knew the cells were sensitive to dopamine, but nobody had been able to put the two together."

Keyword: Miscellaneous
Link ID: 5809 - Posted: 07.15.2004

Last year a remarkable exhibit came to light. Hidden in the vaults of a London museum was a scrap of paper containing a few strands of hair. The paper was crudely fashioned into an envelope but the words on it immediately caused a stir: "Hair of His Late Majesty, King George 3rd." For Professor Martin Warren, it was the clue that would help him finally solve the mystery of King George's illness. His investigation is featured in a BBC documentary, Medical Mysteries. "King George is largely remembered for those periods when he lost his mind. But it's been difficult to explain these attacks, so I was keen to analyse this hair sample," said Professor Warren. When the hair was tested by the Harwell International Business Centre for Science & Technology in Didcot, Oxfordshire, the results were surprising. The king's hair was laden with arsenic. It contained over 300 times the toxic level. "This level is way above anything we were expecting - it's taken us completely by surprise." Far from being an answer, this remarkable finding was just the start of Warren's detective work. In King George's time, his bizarre behaviour and wild outbursts were treated as insanity. He was bound in a straight-jacket and chained to a chair to control his ravings. King George was officially mad. It wasn't until the 1970s that a new and controversial diagnosis was made. Two psychiatrists - Ida MacAlpine and her son Richard Hunter - revisited the king's medical records and noticed a key symptom; dark red urine - a classic and unmistakable sign of a rare blood disorder called porphyria. Porphyria can be a devastating disease. In the acute form, it can cause severe abdominal pain, cramps, and even seizure-like epileptic fits. (C)BBC

Keyword: Neurotoxins
Link ID: 5808 - Posted: 07.14.2004

US scientists have developed a tool that, for the first time, monitors live brain activity down to the cellular level. It could be used to tell scientists exactly how drugs affect specific neurons involved in psychiatric disorders, say its creators. Dr Alison Barth and colleagues at Carnegie Mellon University hope this, in turn, could lead to new treatments. Their findings appear in the Journal of Neuroscience. Scientists have mapped general areas of the brain that perform certain tasks, such as memory, behaviour and perception. However, they have not been able to pinpoint individual nerve cells, or neurons, according to Dr Barth, assistant professor of biological sciences at the university's Mellon College of Science. To try to overcome this limitation, Dr Barth experimented on mice. She changed the genes of the mice so a fluorescent protein would light up whenever a particular nerve cell was activated. In this way, researchers would be able to tell when a drug or a trigger from the environment was acting on a specific neuron by looking for the glow from the fluorescent protein. Using this technique, Dr Barth was able to identify the precise area of the mouse brain, down to the cellular level, involved in processing sensory information from a single whisker.

Keyword: Brain imaging
Link ID: 5807 - Posted: 07.14.2004

COLUMBUS, Ohio – By examining the brain activity of moths, researchers have found that the behavior of these insects isn't ruled entirely by instinct. Rather, they can learn which odors mean food. The findings are more than academic: The researchers hope to develop methods for using trained moths to detect odors of interest for defense industry and law enforcement – such as odors given off by biological and chemical weapons. Animal behaviorists have historically argued that most insects have a programmed response to a variety of situations, such as knowing which odors signal the presence of food and mates. But scientists are discovering that animals don't always instinctively know what to do. In these cases, they have to learn, said Kevin Daly, the study's lead author and a research scientist in entomology at Ohio State University. He and his colleagues used tiny electrodes implanted in the heads of sphinx moths to continuously monitor the insect's neuronal activity and feeding behavior before, during and after training the animal that one odor meant food – sugar water – was on the way and another odor did not.

Keyword: Learning & Memory; Chemical Senses (Smell & Taste)
Link ID: 5806 - Posted: 06.24.2010

Some primatologists have argued that to understand human nature we must understand the behavior of apes. In the social interactions and organization of modern primates, the theory goes, we can see the evolutionary roots of our own social relationships. In the genomic era, as scientists become more adept at extracting biological meaning from an ever expanding repository of sequenced genomes, it is likely that our next of kin will again hold promising clues to our own identity. Comparing primate genomes is an approach that can help scientists understand the genetic basis of the physical and biochemical traits that distinguish primate species. James Sikela and colleagues, for example, collected DNA from humans, chimpanzees, bonobos, gorillas, and orangutans to identify variations in the number of copies of individual genes among the different species. Their work is published in this month's issue of the open-access journal, PLoS Biology. Overall, Sikela and colleagues found more than 1,000 genes with changes in copy number in specific primate lineages. All the great ape species showed more increases than decreases in gene copy numbers, but humans showed the highest number of genes with increased copy numbers, at 134, and many of these duplicated human genes are implicated in brain structure and function.

Keyword: Evolution
Link ID: 5805 - Posted: 07.14.2004

Montreal, . Scientists at the Montreal Neurological Institute at McGill University have discovered a gene that is necessary for the correct development of the part of the brain that controls autonomic functions such as heart rate, bronchial dilation and gut peristalsis. In a study published in the Proceedings of the National Academy of Sciences of the USA, Dr. Stefano Stifani and colleagues have demonstrated for the first time that disruption of this gene causes a dramatic loss of these particular nerve cells. During the development of the nervous system, there are a number of critical events that generate different types of nerve cells in particular locations of the brain and at particular times. “We found that specific types of hindbrain visceral motor nerve cells do not develop when the function of a gene called Runx1 is disrupted in mice, while other types of nerve cells develop normally”, explained Dr. Stefano Stifani, Associate Professor of Neurology and Neurosurgery and Anatomy and Cell Biology. “This has never been shown before and it is an important step in understanding how these nerve cells form during normal development.” The hindbrain visceral motor nerve cells normally control the ability to maintain a stable internal environment in response to internal or external influences. Problems associated with their development or function could have important implications for the control of vital body functions such as blood pressure, heart rate, and electrolyte balance.

Keyword: Development of the Brain
Link ID: 5804 - Posted: 06.24.2010

Patients with the movement disorder Parkinson’s disease have seen benefits from drugs that target brain chemicals. Unfortunately the advantages can decline over time. Recently, however, scientists devised and refined a different strategy, termed deep brain stimulation, which now provides patients with an additional option. Research indicates that this electricity-based technique can alter brain activity and help many patients achieve greater control over their movements. Continued investigations into how deep brain stimulation creates its benefits will allow researchers to further improve the technique for Parkinson’s and also help them find ways to use it for the treatment of other brain ailments. Electricity keeps Justin Timberlake’s tunes blaring on the CD player, the milk chilled in the refrigerator, and the living room well lit. In recent years, the power of electricity has reached a whole new level. Scientists now have discovered an electricity-based technique that can aid the malfunctioning brain. Comprised of a brain implant that delivers electrical pulses, the strategy, termed deep brain stimulation, influences cell activity and alleviates the movement problems that mark the brain disorder Parkinson’s disease (PD). Copyright © 2004 Society for Neuroscience

Keyword: Parkinsons
Link ID: 5803 - Posted: 06.24.2010

Jim Giles Tommy McHugh was sitting on the toilet when his life changed. He felt a sudden and extreme headache, but something far more serious was occurring: blood was leaking from an artery in his brain. McHugh was suffering from a cerebral haemorrhage — an event that hospitalized him, altered his personality and, he says confidently, was the best thing that ever happened to him. Standing in the bright London sunshine three years later, McHugh describes his new life. If I wasn't there, he tells me, he would be manically painting, sculpting or writing poetry. It's a statement those who knew McHugh before his stroke would find hard to believe. A former builder and heroin addict who has had stints in jail for violent offences, McHugh had no former interest in art. Now he spends almost all his time compulsively creating. "My life is 100% better," he grins. McHugh's story is extraordinary but not completely unique. A handful of similar cases have been identified by neurologists in the United States. There are even rumours that Tom Cruise may play the part of one such patient in a forthcoming film. While the number of subjects remains small, only tentative conclusions can be drawn about how these artistic urges occur. But studies of patients such as McHugh could shed light on how our brains create art. "People like Tommy could reveal the key to artistic creativity," says Mark Lythgoe, a neuroscientist at University College London (UCL). ©2004 Nature Publishing Group

Keyword: Miscellaneous
Link ID: 5802 - Posted: 06.24.2010

MADISON - A newly published study by a University of Wisconsin research team points the way to solving two of life's seemingly eternal but unrelated mysteries: how birds that migrate thousands of miles every year accomplish the feat on very little sleep and what that ability means for humans who are seriously sleep-deprived or face significant sleep problems. The study, published online in the July 13 issue of PloS (Public Library of Science) Biology, found that a group of sparrows studied in the laboratory dramatically reduced how long they slept during the time they would ordinarily be migrating. But they were nonetheless able to function and perform normally despite their sleep deprivation. During times when the birds were not migrating, however, sleep deprivation appeared to impair their performance - similar to what happens to sleep-deprived humans. If researchers ascertain how the birds do so well on so little sleep during migration, the finding could benefit people who need to stay awake and function at a high level for long periods of time, as well as those who suffer from sleep disorders of various kinds. In addition, sleep in the migrating birds was similar to sleep changes that typically occur in humans with depression or bipolar disorder.

Keyword: Sleep; Animal Migration
Link ID: 5801 - Posted: 07.14.2004

Eight percent of men experience red-green color blindness, which results from mutations in genes that code for light-sensitive pigments. But a new study suggests that even men who aren't color blind may see the world differently than women do thanks to natural selection. Brian Verrelli of Arizona State University and Sarah Tishkoff of the University of Maryland analyzed genetic data from 236 people from around the world. Specifically, they studied a gene on the X chromosome known as OPN1LW, which codes for a protein that detects visible light in the red spectrum. Exchange of material between this gene and a neighboring gene associated with green light leads to a high amount of genetic variation but can result in color blindness if the process goes amiss. Among the study participants the researchers found 85 variants of the gene. “That's approximately three times higher than what you see at any other random gene in the human genome,” Tishkoff says. “Usually it's a bad thing to have too much change in a gene, and natural selection gets rid of it. But in this case we're seeing the reverse.” The increased variation enhances the ability to discriminate between colors in the red-orange spectrum, particularly among females because they have two copies of the X chromosome. Previous research in other primates has suggested that enhanced red vision in females allows them to better distinguish between berries and foliage when they are gathering food, Verrelli explains. If females did the gathering in prehistoric times, as many experts believe, that may explain why genetic variation promoting color sensitivity persists today. “We can't explicitly test it, but the model fits,” Verrelli says. The results will appear in the September issue of the American Journal of Human Genetics. --Sarah Graham © 1996-2004 Scientific American, Inc

Keyword: Vision; Genes & Behavior
Link ID: 5800 - Posted: 06.24.2010