Michael Hopkin A mentally stimulating career may help to reduce the risk of Alzheimer's disease, research suggests. According to a study carried out in the United States, those who develop the debilitating form of dementia are more likely to have had jobs that do not tax the brain. The discovery lends weight to the 'use it or lose it' theory, says Kathleen Smyth of Case Western Reserve University in Cleveland, Ohio, who led the research. Experts have previously suggested that keeping the mind active, through reading or crossword puzzles, can help to stave off dementia in old age. The latest work, however, shows that mental stimulation throughout life can influence the development of Alzheimer's. The researchers examined 122 people with Alzheimer's disease and 235 healthy subjects, and compared the mental demands they had faced throughout their careers, from their twenties right through to their fifties. The average level of mental strain on the two groups was equal during their twenties. But those without Alzheimer's tended to have had jobs that were more mentally taxing from their thirties through to retirement, the researchers report in the journal Neurology1. "In their thirties, forties and fifties there was a divergence that persisted," Smyth says. ©2004 Nature Publishing Group

Keyword: Alzheimers
Link ID: 5969 - Posted: 06.24.2010

CLEVELAND: Researchers at University Hospitals of Cleveland and Case Western Reserve University School of Medicine have found a new and interesting link between the mental demands of an occupation and later development of Alzheimer's disease. Their study is published in the August 10th issue of Neurology, the scientific journal of the American Academy of Neurology. According to the study, people with Alzheimer's are more likely to have had less mentally stimulating careers than their peers who do not have Alzheimer's. The research team, led by Kathleen Smyth, PhD, and Robert Friedland, MD, of the University Memory and Aging Center, studied 122 people with Alzheimer's and 235 people without the disease, all of whom were more than 60 years old. They gathered information about their occupational history over 40 years, from ages 20 through 60. "We didn't simply classify study subjects as blue collar or white collar," said Dr. Smyth. "We drilled down further into occupational tasks, to classify a job as mentally stimulating based on its complexity, variety of tasks, whether it involved creative thinking or manipulation of data. Less mentally demanding jobs included more routine and monotonous tasks."

Keyword: Alzheimers
Link ID: 5968 - Posted: 08.10.2004

Patrick Barkham Derided for their pathological inability to listen, particularly to words such as "commitment" and "washing-up", men are actually better at hearing and identifying everyday noises than women, according to new research. Even more remarkably, a greater number of men correctly identified the sounds of a number of different household chores in the tests, suggesting a closer familiarity with cleaning and tidying the home than many women might expect. In tests carried out by Dolby Laboratories, in which people had to identify common sounds emanating from different directions, men beat the women by two to one, with 60% of the tests won by men compared with 28% by women. Twelve per cent of tests were drawn. While 16% of women identified the sound of a toilet flushing, 40% of men instantly recognised the noise. One in five men identified the clattering of pots and pans compared with 4% of women. And 94% of men recognised the sound of a vacuum cleaner, which almost a quarter of women failed to identify. © Guardian Newspapers Limited 2004

Keyword: Hearing; Sexual Behavior
Link ID: 5967 - Posted: 06.24.2010

US scientists believe they have discovered why boys born too early struggle more with schooling in later life than premature baby girls. Doctors have known premature baby boys fare worse than premature baby girls and that both have smaller brains than babies born at the normal time. Now a team at Stanford University have found specific brain areas are much smaller in preterm baby boys. Their findings appear in the journal Pediatrics. Compared with girls, premature boys tend to struggle more with speech and language and can have a harder time at school as a result. Dr Allan Reiss and colleagues were interested to find out whether there might be a physical reason that could explain this difference. They looked at the brains of 96 eight-year-old children, 65 of whom had been born prematurely. Magnetic resonance imaging scans showed the children who had been born prematurely had smaller brains than the other children, as would be expected from previous study findings. The volumes of both grey and white brain matter, the two forms that the brain is made of, were reduced in the premature group. However, when the researchers divided this group's scans by gender they found a difference that has not been shown before. (C)BBC

Keyword: Development of the Brain; Sexual Behavior
Link ID: 5966 - Posted: 08.09.2004

British scientists have set up an internet-based library of people stammering which they say will help research into the speech impediment. The archive consists of around 150 recordings made over a decade. Three million Britons are thought to have suffered from the condition at some point during their lives. The database will bring "new hope" to people who stammer, said the project's head Professor Peter Howell from University College London. Celebrity stammerers include pop idol star Gareth Gates. King Charles I, Napoleon Bonaparte, Charles Darwin, Isaac Newton, Aristotle, Marylin Monroe and Winston Churchill are also said to have battled with the condition. Prof Howell said: "Research using these data should place us, better than ever before, in a position to offer accurate and personal advice to help people control their stammers." He decided to compile the stammers due to the lack of available data on the subject. Prof Howell said: "Researchers who want to investigate stammered speech really have a daunting task. "They have to build expertise, get the right equipment, and develop an administrative structure to locate patients as well as obtaining ethical permission. Then comes the actual research. "Once our database is available it will provide terrific encouragement for those thinking of studying in this important area." (C)BBC

Keyword: Language
Link ID: 5965 - Posted: 08.09.2004

Matt Ridley The more we find out about genomes, the more humiliating the news they bring us. The human genome turns out to be profoundly ordinary. We have known for decades that human beings have one fewer chromosome than chimpanzees, which should have been ample warning. We have known for years that grasshoppers have three times as much DNA per cell as we do, deep sea shrimps ten times, salamanders 20 times and African lungfish a staggering 40 times. But we still kidded ourselves until just the last few years that human beings would prove to have more genes, arranged in a more sophisticated way, than most other creatures. How else to explain our exquisite brains? We have 25,000 genes (or recipes for protein molecules) which is the same as a mouse, just 6,000 more than a microscopic nematode worm and 15,000 fewer than a rice plant. However sophisticated our brains are, it is not reflected in our genes. This has led some to suggest that we have been exaggerating the role of genes in shaping our brains. In fact, it reminds us that recipes are more than lists of ingredients. How those ingredients are cooked is also crucial. And the instructions for cooking up a body are hidden in the genome too - between the genes themselves. The deciphered text of the human genome is being joined by an increasing number of other animal volumes on the laboratory shelf. The mouse, rat and chimp genomes are done; the fly, worm and two fish genomes have been ready for a while. The chicken is coming soon; the kangaroo and the dog will follow. Each of them is a book of stupendous length and compendious tedium in itself, written in a four-letter alphabet with no punctuation, and consisting of sometimes upwards of 95 parts gobbledegook to two parts of sense - not exactly bedtime reading.

Keyword: Genes & Behavior
Link ID: 5964 - Posted: 08.09.2004

Researchers are one step closer to unravelling the mystery of medically unexplained pain such as chronic low back pain, which continues to baffle doctors. A study exploring the experience of pain in hypnotised volunteers has found that some types of pain which cannot be traced to a medical condition may have its origins in our brains, not in our bodies. The study by University College London and University of Pittsburgh Medical Centre found that volunteers who felt pain as a result of hypnotic suggestion showed strikingly similar brain activity to those subjected to physical pain via pulses of heat at 49 degrees Celsius. The study, to appear in the next issue of NeuroImage, also found that when the volunteers were asked to simply imagine that they felt the same pain, they had significantly different brain activity than under hypnotised and physical pain conditions. Dr. David Oakley, Director of UCL's Hypnosis Unit, says: "The fact that hypnosis was able to induce a genuine painful experience suggests that some pain really can begin in our minds. People reporting this type of pain are not simply imagining it."

Keyword: Pain & Touch
Link ID: 5963 - Posted: 08.09.2004

Traces of the antidepressant Prozac can be found in the nation's drinking water, it has been revealed. An Environment Agency report suggests so many people are taking the drug nowadays it is building up in rivers and groundwater. A report in Sunday's Observer says the government's environment watchdog has discussed the impact for human health. A spokesman for the Drinking Water Inspectorate (DWI) said the Prozac found was most likely highly diluted. The newspaper says environmentalists are calling for an urgent investigation into the evidence. It quotes the Liberal Democrats' environment spokesman, Norman Baker MP, as saying the picture emerging looked like "a case of hidden mass medication upon the unsuspecting public". He says: "It is alarming that there is no monitoring of levels of Prozac and other pharmacy residues in our drinking water." Experts say the anti-depression drug gets into the rivers and water system via treated sewage water. (C)BBC

Keyword: Depression
Link ID: 5962 - Posted: 08.09.2004

A vaccine containing mercury given to babies when they are eight weeks old is to be scrapped amid fears of a link with autism. The move follows recent research in America that suggests a connection between the mercury used to preserve the whooping cough vaccine, and autism. The jab, without mercury, will be given as part of a new five-in-one vaccine. The Department of Health has always maintained there is no evidence of such a link. Doctors are also being told to switch from the live polio vaccine, currently given by mouth, to a "killed" vaccine injection to avoid rare cases of polio contamination, according to a report in The Daily Telegraph newspaper. GP Richard Halverson welcomed the "long overdue" changes. He told BBC News: "I welcome the fact that mercury is being withdrawn because it is toxic and should not be injected into babies full stop. "Mercury is one of the most toxic elements on this planet. It has no business being ingested in any form by anyone, it serves no useful purpose, it is dangerous." He also welcomed changes to the polio vaccine, saying it was "disgraceful" that the only cases of paralysis from polio in the UK in the last 15 years had been as a result of the vaccine. (C)BBC

Keyword: Autism; Neurotoxins
Link ID: 5961 - Posted: 08.07.2004

By MARY SPICUZZA About 8 p.m. on Wednesday, doctors at the Children's Hospital at Montefiore Medical Center had already finished more than 10 hours of grueling surgery to separate Carl and Clarence Aguirre, 2-year-old Filipino twins joined at the top of their heads, when they realized things were about to become even more complicated. The surgeons who were working to "tease apart" the boys' brains discovered they were actually fused. Until that moment, they thought the brothers had two separate brains that were tightly pressed together and linked only by veins. "We got to this point and we were stuck," said Dr. James T. Goodrich, the hospital's director of pediatric neurosurgery. "We did a lot of soul-searching at that point." After 90 minutes, the doctors decided to plunge ahead and separate the brains. Many hours later, the two boys lay side by side, each in his own bed, for the first time in their lives. Copyright 2004 The New York Times Company

Keyword: Development of the Brain
Link ID: 5960 - Posted: 08.07.2004

Nathan Seppa Amyloid beta, the waxy protein that litters the brains of Alzheimer's patients, is like a criminal with many arrests but no convictions. Studies have implicated amyloid plaques in the disease, but nobody has proved that they cause it. Now, scientists working with mice report that antibodies tailor-made to attack amyloid can wipe it out and reverse an experimental version of Alzheimer's disease if the intervention begins early enough. What's more, removing amyloid rubbed out its partner in crime, a protein called tau that collects in tangles inside brain cells. The work appears in the Aug. 5 Neuron. This study "provides the strongest experimental evidence to date" that amyloid is the ringleader of Alzheimer's disease, says coauthor Frank M. LaFerla, a neuroscientist at the University of California, Irvine. LaFerla suspects that amyloid collaborates with tau to kill neurons and trigger the confusion and memory loss that mark the disease. In their tests, LaFerla and his colleagues used mice genetically engineered to make excess amyloid and tau. The researchers then injected antibodies against amyloid into the animals' brains. Copyright ©2004 Science Service.

Keyword: Alzheimers
Link ID: 5959 - Posted: 06.24.2010

ITHACA, N.Y. -- If brain size is proportional to body size in virtually all vertebrate animals, Cornell University biologists reasoned, shouldn't eye size and body size scale the same way? While they failed to find a one-size-fits-all rule for eyes, what they learned about the 300 vertebrates they studied helps to explain how animals evolved precisely the orbs they need for everyday life. The biologists reported their findings in the journal Vision Research (August 2004, "The allometry and scaling of the size of vertebrate eyes"). Howard C. Howland, Stacey Merola and Jennifer R. Basarab say they did find a logarithmic relationship between animals' body weight and eye size for all vertebrates, in general: Bigger animals do tend to have bigger eyes, on average. But breaking vertebrates into smaller groups -- such as birds, fishes, reptiles and mammals -- and trying to predict their eye size gets more complicated. And dividing all mammals into groups -- such as rodents and primates -- could make a scientist cross-eyed: Compared with all vertebrates, rodents' eyes are only 61 percent as large as they "should be" if all animals obeyed the general rule, while primates' eyes are 35 percent larger than those of vertebrates as a whole. Except for gorillas, that is.

Keyword: Vision; Evolution
Link ID: 5958 - Posted: 08.07.2004

Every mom and dad can tell you that keeping children busy helps stave off cries of boredom--and now there is scientific backing to prove it. Dr. Anthony Chaston and his research colleague, Dr. Alan Kingstone, have proven, once and for all, that time really does fly when you're having fun. Or, at least, it flies when your attention is engaged. Working in the University of Alberta Department of Psychology, Chaston and Kingstone devised a test that required subjects to find specific items in various images--a sort of "Where's Waldo" activity. However, before the subjects started the test they were told that once they had completed it they would be asked to estimate how much time had passed during their test. There were seven levels of difficulty among the tests. In some cases, the items were easy to find because they were different colours from everything else, or the items were set among just one or two others. In the more difficult tests, the items were placed among many similar looking items, or they didn't even exist in the image, at all. "The harder and harder the search tasks were, the smaller and smaller the estimates became," said Chaston, whose study is published in the latest edition of Brain and Cognition. "The results were super clean--we have created a new and powerful paradigm to get at the link between time and attention."

Keyword: Attention
Link ID: 5957 - Posted: 08.07.2004

Many more people could become infected with vCJD than previously thought, experts have warned. It follows analysis of a probable transmission of the human form of BSE, via a blood transfusion. CJD Surveillance Unit scientists found the patient's genetic make-up differed from that of any other person so far diagnosed with the disease. This suggests that wider groups of people could be at risk than was thought, they write in the Lancet. Professor James Ironside, who led the research, told BBC News Online that just over half of the population were in the same genetic subgroup as the transfusion patient. He said the incubation period for the disease could be longer for this group, and it could also mean they were carrying the disease without being aware of it - but still potentially infecting others via blood transfusions or surgical instruments. (C)BBC

Keyword: Prions
Link ID: 5956 - Posted: 08.06.2004

Winged creature had birdlike senses, fossil X-rays reveal David Perlman, Chronicle Science Editor New evidence gathered from a major advance in X-ray imaging of fossils has established that the winged dinosaur called archaeopteryx could actually fly and had much the same sense of balance and sharp vision found in today's birds. And while its senses were a bit more primitive than its modern evolutionary descendants, the pigeon-sized archaeopteryx was certainly well equipped to navigate over land and forests looking for distant prey, scientists say. The evidence comes from a remarkable technology that allowed University of Texas researchers to scan in three dimensions deep inside the brain case of the priceless 247-million-year-old fossil dinosaur and reveal the workings of its most critical sense organs. The technique -- somewhat similar to computerized CAT scans that doctors use to examine the brains and bodies of their patients -- has resulted in the first complete 3-D models of the interior of the ancestral bird's brain, and an equally detailed cast of its inner ear. ©2004 San Francisco Chronicle |

Keyword: Evolution
Link ID: 5955 - Posted: 06.24.2010

Eighteen years after BSE first emerged in the UK, we still have little idea how to treat people who have contracted the human version, variant Creutzfeldt-Jakob Disease (vCJD). An investigation by New Scientist has revealed that the relatives of people with vCJD are frustrated by the slow progress being made to find new treatments. Time and effort are being wasted researching drugs that simply do not work, they say, while other, radical, treatments are not being made readily available. But while researchers privately disagree over which approaches show most promise, they say there is now a united effort to find a drug best able to save lives. Later this month, the UK government's Medical Research Council will officially launch a trial of potential treatments, after four years of argument over which to test. Called the "PRION-1" trial it will focus on quinacrine, an anti-malarial drug that showed early promise in treating various forms of CJD. The National Prion Disease Clinic at St Mary's Hospital in London has already given the drug to around 20 patients, but the results are not yet in. © Copyright Reed Business Information Ltd.

Keyword: Prions
Link ID: 5954 - Posted: 06.24.2010

Helen Pilcher Assertiveness really is all in the mind. Dominant rats have more new nerve cells in a key brain region than their subordinates, a study reveals. The finding hints that social hierarchies can influence brain structure, and raises questions over the use of standard animal behaviour tests in laboratory research. Yevgenia Kozorovitskiy and Elizabeth Gould from Princeton University, New Jersey, studied the brains of around 40 rats that had been left to form social hierarchies in a semi-natural setting. Their results are published in The Journal of Neuroscience1. In each experiment, four males and two females were placed inside a large box comprising an underground tangle of burrows and chambers and a feeding area above. Within three days, the males had established their preferred pecking order: an aggressive leader who attracted the females and three defensive subordinates. © 2004 Nature Publishing Group

Keyword: Neurogenesis
Link ID: 5953 - Posted: 06.24.2010

Experiments with mice hint that targeting one of the two molecular aggregates gumming up brains with Alzheimer’s disease also rids tissue of the other, as long as treatment starts early enough. This finding and a recent analysis of an interrupted Alzheimer’s vaccine trial in people have brought new life to the idea of immunotherapy for the debilitating disease. An ongoing debate in Alzheimer's research centers on the relative importance of brain plaques (extracellular clumps of a protein fragment called ß amyloid) and tangles (filaments of the protein tau that form inside neurons). Researchers have had difficulty testing the roles of plaques and tangles because no one had created mice that develop both--until last year, when neuroscientist Frank LaFerla of the University of California, Irvine, and colleagues engineered mice that develop plaques and tangles in the same brain regions as the brains of people with Alzheimer’s disease do. In the new work, the team injected antibodies against ß amyloid into the hippocampus of their transgenic mice when the animals were 1 year old. Three days after the injection, plaques in the injected animals had disappeared. Between 5 and 7 days after the injection, tau, which had aggregated within neurons but not yet formed tangles, also had melted away. Additional experiments with a different set of engineered mice suggested that the antibodies can't budge tangles once they have formed, however. Copyright © 2004 by the American Association for the Advancement of Science.

Keyword: Alzheimers
Link ID: 5952 - Posted: 06.24.2010

By Rossella Lorenzi, Discovery News — California ground squirrels heat up their tails to scare away hungry rattlesnakes, U.S. researchers have discovered. The behavior, which is the first deliberate animal signal known to be communicated via infrared radiation, takes advantage of rattlesnakes' ability to detect heat through sensitive structures in their faces called pit organs. "Rattlesnakes are a constant threat to California ground squirrels. Pups make up about 69 percent of the snakes' diet. Adults are not the prey, since they possess blood proteins which are capable of partially neutralizing the venom, allowing them to survive a bite," main researcher Aaron Rundus, of the University of California, Davis, told Discovery News. Due to the venom resistance and the need to defend their young, adult squirrels often confront snake predators with aggressive behaviors such as kicking sand, biting, swiping and most of all, brandishing their tails. "This is a unique snake elicited behavior. It consists of lifting the tail off the ground, piloerecting its fur and waving the tail side to side," Rundus said. Copyright © 2004 Discovery Communications Inc

Keyword: Evolution
Link ID: 5951 - Posted: 06.24.2010

Flight was built into the brain as well as the body of Archaeopteryx. The oldest known bird shares many skeletal features with its dinosaur ancestors, such as teeth and a long bony tail. Yet a CAT scan reveals that Archaeopteryx had the large brain and optic lobes of modern birds, not the brain of a dinosaur, says Angela Milner of the Natural History Museum in London, UK. It is relatively easy to study how a fossil skeleton may have been adapted for flight. However, navigating in a three-dimensional environment also requires a specialised brain. Modern birds have an enlarged brain, optic lobes and keen ears with spatial sensing organs, but little had been known about the brain of Archaeopteryx. So Milner’s team investigated the London specimen of Archaeopteryx, the only one suitable for scanning. A three-dimensional image created from the scan shows the bird had a relatively large cerebellum, “the area where all the coordination and control goes on”, Milner says. © Copyright Reed Business Information Ltd.

Keyword: Evolution; Brain imaging
Link ID: 5950 - Posted: 06.24.2010