People who have migraines are twice as likely to have a stroke as others, researchers estimate. Experts in Canada and the US looked at 14 studies that had shown a link to quantify the exact risk involved. Migraines roughly doubled the stroke risk, while migraines with 'auras' more so than those without interruptions to the sufferers' vision. Women with migraines who were on the oral contraceptive pill appeared to be at particular risk, reserach found. The increased risk of stroke is probably down to the reduced blood flow to the brain which usually occurs in a migraine, the researchers believe. The studies looked at by Dr Ali Samii, neurologist at the University of Washington, and his colleagues, suggest the risk of stroke for migraine sufferers is 2.16 times that for non-sufferers. Those who have migraines with auras are 2.27 times as likely to suffer a stroke and in those with migraines without auras the risk is increased 1.86 times. Three of the studies showed that women migraine sufferers who were also taking oral contraceptives were up to eight times more likely to suffer a stroke than those not taking the pill. The researchers said the latter results were slightly at odds with other studies, which suggest a smaller degree of increased risk for such women - about double. Therefore, they say much more research should be carried out to establish what the risk is. "Given that the use of oral contraceptives is prevalent among young women, the potential risk of stroke among women with migraine who are also users of oral contraceptives must be further investigated," they said in their paper which is due to be published in the British Medical Journal. (C)BBC

Keyword: Stroke; Pain & Touch
Link ID: 6585 - Posted: 12.14.2004

Eating a low calorie diet may help to reduce the risk of Parkinson's disease, research suggests. A team from the US National Institute on Ageing found a long-term reduction in caloric intake protects rhesus monkeys from developing the disease. They believe restricting caloric intake switches on mechanisms which protect the brain cells lost in people diagnosed with Parkinson's. Details are published in Proceedings of the National Academy of Sciences. A number of studies have suggested the normal ageing process causes a loss of brain cells that produce a key chemical called dopamine in an area of the brain called the substantia nigra. It is thought that Parkinson's disease speeds up the loss of these cells, leading to the problems with movement associated with the condition. Limiting the number of calories in the diet has been shown to have a powerful effect in slowing down the ageing process. The US team decided to examine whether it could also prevent the development of Parkinson's symptoms in monkeys. For six months monkeys received a diet with 30% fewer calories than the control diet. At that point, the monkeys were injected with a toxin that causes a Parkinson-like disease. The calorie-restricted monkeys showed better control over their movement, and higher levels of dopamine in their brains. They also had higher levels of a growth factor, GDNF, which the researchers believe may protect brain cells from destruction. The researchers say their work suggests that long-term caloric restriction may reduce the risk of developing Parkinson's by turning on production of this protective growth factor. (C)BBC

Keyword: Parkinsons; Obesity
Link ID: 6584 - Posted: 12.14.2004

By ANAHAD O'CONNOR Looking back, Denise Watkins is convinced a sore throat disabled her son one year ago. His bizarre obsessions emerged not long after, first the constant nightmares about snakes and alligators, then the relentless hand washing that left his skin raw and chapped. Mrs. Watkins, who lives in Lakeland, Fla., was told that her son, Will, had obsessive-compulsive disorder. But it seemed odd, Ms. Watkins thought. Will was only 5 years old, and his illness seemed to burst out of nowhere. "In a matter of weeks," she said, "this was a totally different child." Then one day, buried on a Web site about mental illness, her husband noticed a small "blip" on children who develop a sudden, severe form of obsessive-compulsive disorder after a bout of strep throat. Mrs. Watkins read the description, decided that Will fit the pattern, and thus became part of a small but growing number of parents who blame a common bacterial infection for the psychiatric illness of a son or daughter. About one child in 1,000 may be afflicted, but some experts say the number is higher if milder cases that escape notice are included. The condition is known as Pandas, or pediatric autoimmune neuropsychiatric disorder associated with streptococcal infection, and scientists know so little about it that some question whether it even exists. Copyright 2004 The New York Times Company

Keyword: Emotions
Link ID: 6583 - Posted: 12.14.2004

By ANAHAD O'CONNOR SEATTLE - Sitting in a small evaluation room at the University of Washington, apprehension written on her face, Christa Zamora turned her eyes toward her son Connor and contemplated his future. A talkative and animated 2-year-old, Connor appears normal, Ms. Zamora said, but it is too soon to be certain. Doctors diagnosed autism in her older son, Cameron, just before he turned 3. And with Connor, who is also at risk for developing the devastating neurological disorder, which runs in families, she has decided to be proactive, enrolling him in an early diagnosis study for children as young as 16 months. "I'm very concerned," said Ms. Zamora, who is also worried about her third child, a boy due in February. "Connor seems to be past the danger zone. But Cameron repeats himself a lot, and sometimes I see Connor doing the very same things." Across the country, thousands of toddlers like Connor are joining studies that could signal new hope for a baffling childhood disorder. Copyright 2004 The New York Times Company

Keyword: Autism
Link ID: 6582 - Posted: 12.14.2004

Every year, millions of people try to look younger by taking injections of Botox, a prescription drug that gets rid of facial wrinkles by temporarily paralyzing muscles in the forehead. Although best known as a cosmetic procedure, Botox injections also have been approved by the Food and Drug Administration (FDA) to treat uncontrolled blinking (blepharospasm), lazy eye (strabismus), involuntary muscle contractions in the neck (cervical dystonia) and acute underarm sweating (severe primary axillary hyperhidrosis). Botox users might be surprised to learn that they're actually receiving minute injections of a bacterial neurotoxin called botulinum, one of the most poisonous substances known. Exposure to large amounts of botulinum bacteria can cause a paralytic, sometimes-fatal disease called botulism. Last month, several Floridians were hospitalized with botulism after receiving injections of an anti-wrinkle treatment that authorities suspect was a cheap, non-FDA-approved imitation of Botox. The botulinum toxin works by invading nerve cells, where it releases an enzyme that prevents muscle contraction. In recent years, scientists have determined that the enzyme binds to specific sites on proteins called SNAREs, which form a complex in the synapse between nerve and muscle cells. Without SNAREs, nerves cannot release the chemical signals that tell muscle cells to contract, and paralysis results.

Keyword: Neurotoxins
Link ID: 6581 - Posted: 12.14.2004

The "Grand Theft Auto" series of video games is one of the industry's most popular, and also one of the most controversial. This holiday season brings another sequal: "Grand Theft Auto: San Andreas." In it, players control a character who participates in gangland wars, murders police officers and assaults prostitites. The game is expected to sell well enough to rival a blockbuster movie. "In this game, you play the part of a psychopath, basically," says Douglas Gentile, a psychologist at Iowa State University. "You run around the street, you can run down pedestrians with the car, you can do carjackings, you can do drive-by shootings, you can run down to the red-light district, pick up a prostitute, have sex with her in your car, and then kill her to get your money back. Most parents are unaware that this most popular game in the country has such very adult themes in it." Gentile is also research director for the National Institute on Media and the Family, a group which recently held a press conference on Capitol Hill along with concerned lawmakers to warn parents about the content of today's games. Perhaps even more controversial this year than "Grand Theft Auto" is "JFK: Reloaded," in which you recreate the assassination of John F. Kennedy. © ScienCentral, 2000- 2004

Keyword: Aggression
Link ID: 6580 - Posted: 06.24.2010

Bird songs have inspired musicians and poets alike. Now, researchers looking into what inspires young birds to learn them are finding they use a variety of methods to copy the adults' songs. Fernando Nottebohm, an animal behavior scientist at The Rockefeller University in New York City, and his postdoctoral associate Wan-Chun Liu observed and recorded groups of juvenile zebra finches learning to sing. They used a computer program developed at Rockefeller to analyze similarities in the singing patterns, and found that the birds tended to imitate sounds in two ways—by repeating an early syllable, or by approximating the whole song at once. Both styles appear to work well. Liu notes, "whatever strategy they are using, eventually they can produce a very good imitation from their father." Nottebohm explains the difference: "Imagine a series of repetitions of a same vowel—A A A A A A A A. Then the second A is gradually turned into an R, the third one into a T, the fourth one into an I, the fifth one into an S, the sixth one into a T, the seventh one into and I and the last one into a C. When you are done, and the changes are slow and proceed at different paces for each position in this eight letter run; A A A A A A A A has become A R T I S T I C. That, in a nutshell, is what the birds that follow the 'repetition strategy' end up doing. Those that work starting more globally produce a slurred, almost unrecognizable initial version of ARTISTIC, of about the right length, and then they start to improve each part of that statement, also gradually and a various speeds, ending up, like the colleagues, with the same statement." © ScienCentral, 2000- 2004.

Keyword: Language; Sexual Behavior
Link ID: 6579 - Posted: 06.24.2010

Of all the world's animals, only humans, some kinds of birds and perhaps some porpoises and whales learn the sounds they use to communicate with each other through a process of listening, imitation and practice. For the rest, including nonhuman primates, these sounds develop normally in the absence of external models. Now Rockefeller University scientists have found that zebra finches, songbirds native to Australia, use infant-like strategies to learn their song. Some finches focus on perfecting individual song components, referred to as "syllables," while others practice longer patterns called motifs. Which strategy they choose, or what combination of strategies, seems to depend on what their siblings are doing. In time, all are able to sing the same adult song. The results, reported in the December 13 online issue of Proceedings of the National Academy of Sciences, are the first to show a social influence on how birds learn their song by analyzing song-learning with birds kept in family groups rather than in isolation chambers. The Rockefeller team also shows for the first time that individual birds, of the same species, can follow different strategies to get to the same end point of singing the adult song. Until now, scientists thought that the vocal learning process in birds was mainly a matter of filling in details in a pre-existing developmental program. If so, then this program is, in zebra finches, a very flexible one.

Keyword: Sexual Behavior; Language
Link ID: 6578 - Posted: 12.14.2004

SAN JUAN, Puerto Rico, -- The inability to identify the smell of lemons, lilac, leather and seven other odors predicts which patients with minimal to mild cognitive impairment (MMCI) will develop Alzheimer's Disease, according to a study presented today at the American College of Neuropsychopharmacology (ACNP) annual meeting. For patients with MMCI, the odor identification test was found to be a strong predictor of Alzheimer's Disease during follow-up, and compared favorably with reduction in brain volumes on MRI scan and memory test performance as potential predictors. "Early diagnosis of Alzheimer's Disease is critical for patients and their families to receive the most beneficial treatment and medications," says lead researcher D.P. Devanand, MD, Professor of Clinical Psychiatry and Neurology at Columbia University and Co-Director of the Memory Disorders Center at the New York State Psychiatric Institute. "While currently there is no cure for the disease, early diagnosis and treatment can help patients and their families to better plan their lives." Smell identification test results from Alzheimer's disease patients, MMCI patients and healthy elderly subjects were analyzed to select an optimal subset of fragrances that distinguished Alzheimer's and MMCI patients who developed the disease from healthy subjects and MMCI patients who did not develop Alzheimer's.

Keyword: Alzheimers; Chemical Senses (Smell & Taste)
Link ID: 6577 - Posted: 12.14.2004

The drug methylphenidate (brand name Ritalin) increased activity in brains of children with attention-deficit/hyperactivity disorder (ADHD) as well as those with a reading disorder, researchers at Yale report in the American Journal of Psychiatry. "During a test of divided attention, Ritalin increased activation in the basal ganglia, a structure of the brain involved in cognition and behavior," said first author Keith Shafritz, former graduate student in the interdepartmental Neuroscience Program at Yale and now a research associate at Duke University Medical Center. "We saw this activation in children with ADHD and those with reading disorder." The study used functional magnetic resonance imaging (fMRI) to analyze the effect of the drug on brain function. Researchers found that adolescents with ADHD or reading disorder who were on placebo (not medicated) had less activation of the basal ganglia than a group of healthy participants. When the same participants received Ritalin, the drug normalized the activation, which relates to the amount of blood flow to a specific brain region in response to a cognitive task. ADHD is characterized by inattention, but previous neuroimaging studies have examined the brain dysfunction associated with impulsivity. "This is one of few studies that used a test for attention rather than a cognitive test for impulsivity," said Shafritz. "It is also the first study, using fMRI to find that the attention circuitry in the brain is directly affected by ADHD."

Keyword: ADHD; Dyslexia
Link ID: 6576 - Posted: 12.14.2004

Helen Pearson By transforming the features of Margaret Thatcher into those of Marilyn Monroe, researchers have revealed hints about how our brains put a name to a face. Neuroscientists already know that certain spots in the brain play a vital role for recognizing a familiar face, even as it changes with age or a new hairstyle. But they have not been clear precisely what each area does. Using mugshots of celebrities, Pia Rotshtein at University College London and her colleagues have shown that there are at least three separate areas for processing and recognising faces. One processes the physical features of the face, one decides whether or not the face is known, and a third retrieves information about that person, such as their name. Rothstein's team used a computer to create a series of images in which the countenance of film star Marilyn Monroe gradually morphed into that of former British prime minister Margaret Thatcher, or that of James Bond actor Pierce Brosnan transformed into current prime minister Tony Blair. Although the physical features gradually change from one face into another, the researchers showed that subjects looking at the images tend to "suddenly flip" from seeing Marilyn to seeing Maggie, explains team member Jon Driver. ©2004 Nature Publishing Group

Keyword: Vision
Link ID: 6575 - Posted: 06.24.2010

By Rowan Hooper In 1995, the Supreme Court of Georgia heard a lawyer make a novel argument. He had read a study describing violent behavior shared by several generations of men in a Dutch family. Scientists had identified a mutated gene shared by all the violent men, and that's what got the lawyer's brain ticking. The accused, argued the lawyer, might carry a gene -- like the men in the Dutch family -- that predisposed him to violence. (The lawyer's client was on trial for murder.) Therefore, went the argument, the accused did not have free will, was innocent of the murder and should be acquitted. The defense, an attempt at legal trickery remarkable even for a lawyer, failed. However, scientific discoveries, particularly advances in neuroscience, are nevertheless having profound consequences for legal procedure. For example, the insanity plea in the United States currently requires that the accused does not know, because of mental illness, that he did wrong. The insanity plea derives from the M'Naghten rule, a case from English law. In 1843, a man named Daniel M'Naghten attempted to assassinate the British prime minister; at his trial, he was found to be insane and the trial was abandoned. From that point on, lawyers saw the power of mounting an insanity defense, and many such claims were made. © Copyright 2004, Lycos, Inc.

Keyword: Aggression
Link ID: 6574 - Posted: 06.24.2010

The brain goes through three separate stages to decide if it recognises a face, scientists claim. A team from University College London says the first assesses a face's physical aspects. The second decides if it is known or unknown. If it is a recognisable face, the third part puts a name to it. The researchers say their study, published in Nature Neuroscience, could help those people with dementia who lose their ability to recognise faces. The researchers say analysing how we respond to the stages of "morphing" a recognisable figure such as Margaret Thatcher into Marilyn Monroe gives clues as to how we process the facial features we see. Their study found the brain tries to pin a single identity on a face, even if it looks like a mix of two people. A face that was 60% Marilyn Monroe and 40% Margaret Thatcher will be identified as an older version of Marilyn Monroe. But an image which is 40% Marilyn and 60% Maggie will be seen as the "sexier" side of Margaret Thatcher, say the researchers. In the study, volunteers were then shown morphed faces and asked to identify each one. They then used fMRI (functional Magnetic Resonance Imaging) scans to monitor brain activity. It was found that the inferior occipital gyri at the back of the brain were found to be particularly sensitive to slight physical changes, such as wrinkles, in the faces. (C)BBC

Keyword: Miscellaneous
Link ID: 6573 - Posted: 12.13.2004

Scientists at Bangor University have discovered a patient who appears to possess a "sixth sense" that allows him to recognise sad faces. The 52-year-old "patient X" suffered two strokes which damaged the brain areas which process visual signals. Although he cannot see, researchers found that that the patient was able to identify angry or happy human faces. Scans showed that when the man looked at faces with emotion, another part of his brain, the amygdala, was activated. The small almond-shaped structure is known to respond to non-verbal signs of anger, defensiveness, avoidance and fear. The results of the study are published in the online edition of Nature Neuroscience on Sunday. Dr Alan Pegna of the school of psychology at the University of Wales, Bangor, led the research team with colleagues in north Wales and Geneva University Hospital. They found that when "patient X" was shown images of shapes like circles and squares, he was only able to make wild guesses about what they were. Nor was he able to identify the sex of "deadpan" male and female faces with any degree of success, or tell the difference between "normal" and jumbled faces. But when the patient was asked to identify angry or happy human faces, he did so with an accuracy of 59% - significantly higher than would be expected by chance. (C)BBC

Keyword: Vision; Emotions
Link ID: 6572 - Posted: 12.13.2004

UCSF scientists have found that the brains of rats can be trained to learn an alternate way of processing changes in the loudness of sound. The discovery, they say, has potential for the treatment of hearing loss, autism, and other sensory disabilities in humans. It also gives clues, they say, about the process of learning and the way we perceive the world. "We addressed a very fundamental question," says Daniel B. Polley, PhD, lead author of the study. "When we notice a sound getting louder, what happens in our brain so that we know it's getting louder?" Polley is a postdoctoral research fellow in the laboratory of senior author Michael M. Merzenich, PhD, co-director of the Coleman Memorial Laboratory in the UCSF Keck Center for Integrative Neuroscience and UCSF professor of otolaryngology. The study was published recently in Proceedings of the National Academy of Sciences (November 16, 2004). "This is a very old idea," Polley notes. "How to relate the bigness of a stimulus to the bigness of its internal representation in the brain." Over the centuries, philosophers and scientists have put together a picture of how our brains model the world through the mechanism of our senses. Physical stimuli such as light, sound, and touch are converted by our sensory organs -- eyes, ears, and skin -- into electrical signals, which are processed by neurons in different areas of the brain. As those neurons fire, we see, hear, and feel. When the light or sound changes in intensity, our neurons fire faster or slower in direct ratio to the change. That ratio varies depending on the sense involved, but is constant for each sense: the louder a sound, the faster the neurons in the auditory cortex fire.

Keyword: Hearing
Link ID: 6571 - Posted: 12.13.2004

James Owen in London for National Geographic News Anyone who has watched crows, jays, ravens and other members of the corvid family will know they're anything but "birdbrained." For instance, jays will sit on ant nests, allowing the angry insects to douse them with formic acid, a natural pesticide which helps rid the birds of parasites. Urban-living carrion crows have learned to use road traffic for cracking tough nuts. They do this at traffic light crossings, waiting patiently with human pedestrians for a red light before retrieving their prize. Yet corvids may be even cleverer than we think. A new study suggests their cognitive abilities are a match for primates such as chimpanzees and gorillas. Furthermore, crows may provide clues to understanding human intelligence. Published tomorrow in the journal Science, the study is co-authored by Nathan Emery and Nicola Clayton, from the departments of animal behavior and experimental psychology at Cambridge University, England. They say that, while having very different brain structures, both crows and primates use a combination of mental tools, including imagination and the anticipation of possible future events, to solve similar problems. They base their argument on existing studies. Emery and Clayton write, "These studies have found that some corvids are not only superior in intelligence to birds of other avian species (perhaps with the exception of some parrots), but also rival many nonhuman primates." © 2004 National Geographic Society.

Keyword: Evolution; Intelligence
Link ID: 6570 - Posted: 06.24.2010

San Juan, Puerto Rico, – A new study conducted in rats by the National Institutes of Health (NIH) and McLean Hospital/Harvard Medical School suggests that the misdiagnosis of attention-deficit hyperactivity disorder (ADHD) combined with prescription drug use in children may lead to a higher risk of developing depressive symptoms in adulthood. This work, released at the annual American College of Neuropsychopharmacology (ACNP) conference in Puerto Rico, is among the first to examine the effects of early Ritalin exposure in rats on behavior and brain function during the later periods of life. "Attention-deficit hyperactivity disorder can be a serious medical problem for children and their parents," says lead researcher William Carlezon, Ph.D., director of McLean Hospital's Behavioral Genetics Laboratory and associate professor of psychiatry at Harvard Medical School. "While Ritalin is an effective medication that improves the quality of life for many children with ADHD, accurately diagnosing and identifying the correct treatment regimen for the disorder is essential, especially when considering health effects that can last through adulthood." Ritalin is a generic medication prescribed for children with attention-deficit hyperactivity disorder (ADHD), a condition that consists of a persistent pattern of abnormally high level of activity, impulsivity, and/or inattention. Usually diagnosed in children of preschool or elementary school age, ADHD has been estimated to affect 3 to 12 percent of children and is twice as common among boys. Children with ADHD are also likely to have other disorders, such as a learning disability, oppositional defiant disorder, conduct disorder, depression, or anxiety.

Keyword: ADHD
Link ID: 6569 - Posted: 06.24.2010

The language network of the brain seemed simpler in the past. One brain area was recognized to be critical for the production of language, another for its comprehension. A dense bundle of nerve fibers connected the two. But there have always been naysayers who pointed to evidence that failed to fit this tidy picture. Now a study employing a powerful variant of magnetic resonance imaging (MRI) confirms these suspicions. The study will be published December 13, 2004 in the online edition of Annals of Neurology (http://www.interscience.wiley.com/journal/ana). "We were surprised that the two classical language areas were densely connected to a third area, whose presence had already been suspected but whose connections with the classical network were unknown," said lead author Marco Catani, M.D., of the Institute of Psychiatry at King's College London. The authors dubbed this language area "Geschwind's territory" in honor of the American neurologist Norman Geschwind who championed its linguistic significance decades ago. Language is generated and understood in the cortex, the outermost covering of the brain. Paul Broca and Carl Wernicke, 19th Century neurologists, noted that damage to specific cortical areas, which came to bear their names, produced primarily language production or language processing disorders, but not both. A large bundle of nerve fibers was found to connect Broca's and Wernicke's areas, and damage to this pathway also produced language disorders, or aphasias.

Keyword: Language
Link ID: 6568 - Posted: 12.13.2004

If anyone doubted that drug use can damage the brain, new studies using brain scans show methamphetamine abusers' brains have damage similar to dementia, as well as considerable brain inflammation. This ScienCentral news video has more. The poetry in Lee L.'s voice as he describes his great love is hypnotic. "I loved Crystal," he gushes. Lee's not speaking of a person, but methamphetamine, known by its street name, Crystal Meth. "It gave me a sense of power. It made me feel hungry. It made me feel sexual. It made me feel virile. It was like all of the switches in my body and in my brain felt like they finally got turned on." Lee—a 42-year-old composer who asked that his last name not be used in keeping with his involvement in the twelve-step program, New York Crystal Meth Anonymous—hunted down the drug as the days dragged between runs, even though he knew it was doing considerable bodily damage. "The physical body collapses a little every time, certainly in my case, every time that I used," he recalls. "The reward that it got was it hit upon a pleasure center in the brain." © ScienCentral, 2000- 2004.

Keyword: Drug Abuse
Link ID: 6567 - Posted: 06.24.2010

Bruce Bower Here's a discovery worth toasting: Chemical analyses of pottery fragments from a prehistoric village in northern China indicate that people living there between 8,000 and 9,000 years ago concocted a fermented, winelike drink from rice, honey, and fruit. That's the oldest known evidence of an intoxicating beverage, says archaeological chemist Patrick E. McGovern of the University of Pennsylvania Museum of Archaeology and Anthropology in Philadelphia. He led the international team that scrutinized the ancient pottery. Until now, the earliest chemical evidence of wine came from Iranian jars from about 7,400 years ago. Middle Eastern beer-brewing sites date to roughly 5,000 years ago (SN: 10/2/04, p. 216: http://www.sciencenews.org/articles/20041002/bob8.asp). The new results are the latest hints that modern civilizations developed in parallel in eastern Asia and the Middle East, starting around 10,000 years ago, according to McGovern. "The domestication of plants, construction of complex villages, and production of fermented drinks began at the same time in both regions," he says. Copyright ©2004 Science Service.

Keyword: Drug Abuse
Link ID: 6566 - Posted: 06.24.2010