By Emma Wilkinson UK scientists have developed a drug which may halt the progression of Alzheimer's disease. Trials of the drug, known as Rember, in 321 patients showed an 81% difference in rate of mental decline compared with those not taking the treatment. The Aberdeen University researchers said the drug targeted the build-up of a specific protein in the brain. Alzheimer's experts were optimistic about the results, but said larger trials were now needed. Presenting the results at the International Conference on Alzheimer's Disease, Professor Claude Wischik said the drug may be on the market by 2012. Patients with mild to moderate Alzheimer's disease were given either 30, 60 or 100mg of the drug or a placebo. The 60mg dose produced the most pronounced effect - over 50 weeks there was a seven-point difference on a scale used to measure severity of dementia. At 19 months there was no significant decline in mental function in patients taking the drug, the researchers said. Imaging data also suggests the drug may be having its biggest effect in the parts of the brain responsible for memory. The link between clumps or "tangles" of protein inside nerve cells in the brain and Alzheimer's disease was first made over 100 years ago. (C)BBC

Keyword: Alzheimers
Link ID: 11882 - Posted: 07.31.2008

By BINA VENKATARAMAN The song of the blue whale, one of the eeriest sounds in the ocean, has mysteriously grown deeper. The calls have been steadily dropping in frequency for seven populations of blue whales around the world over the past 40 years, say researchers at the Scripps Institution of Oceanography, the National Oceanic and Atmospheric Administration and WhaleAcoustics, a private research company. The scientists analyzed data collected with hydrophones and other tools and found that the songs, which they believe are by males advertising for mates, had lowered by as much as 30 percent in certain populations. Much of the song lies at frequencies too low to be detected by the human ear. The study, though not yet published, has been reviewed by several experts in the field who, in interviews, called the global decline “dramatic,” “significant,” “convincing” and “unequivocal.” Scientists cannot explain why blue whales from places as disparate as the northern Pacific and the Southern Ocean, which surrounds Antarctica, would drop the pitch of their songs. Each blue whale population has a distinct tempo and tone set to its vocals. John Hildebrand, professor of oceanography at Scripps and an author of the study, said the drop might signal a rebound in the population of blue whales since commercial whaling bans began to take effect in the 1970s. Copyright 2008 The New York Times Company

Keyword: Animal Communication; Hearing
Link ID: 11881 - Posted: 06.24.2010

By Melinda Wenner Once an alcoholic, always an alcoholic—the saying is decades old, but scientists have only recently uncovered why it is often true. Long-term alcohol abuse changes the brain, making a person more sensitive to stress and more likely to reach for the bottle to soothe his or her anxiety. According to a new study, drugs that inhibit these stress pathways could help recovering alcoholics stay in control. Scientists at the National Institutes of Health and University College Lon­don bred mice lacking the neuro­kinin 1 receptor (NK1R), a protein involved in the brain’s stress response. The mice were given unlimited access to alcohol-spiked water for 60 days, during which the alcohol content was incrementally raised from 3 to 15 percent. The NK1R-deficient mice consumed far less alcohol—especially later in the trial when alcohol concentration was higher—than the normal mice did. They were also more sensitive to alcohol’s effects than the normal mice were; studies have shown that the more sensitive a person is to alcohol, the less likely he or she is to abuse it. The team then treated 25 highly anxious recovering alcoholics with a drug that blocks the NK1 receptor. After four weeks of hospital treatment, the subjects taking the drug reported fewer spontaneous and stress-induced alcohol cravings than patients given a placebo did. When the scientists used functional MRI to look at the subjects’ brain activity, they found that the treated subjects showed less activity in the insula, a region associated with craving. The scientists believe the drug targets a stress pathway specific to alcoholics because it has been shown to have little effect on stress levels in other types of patients. © 1996-2008 Scientific American Inc.

Keyword: Drug Abuse; Emotions
Link ID: 11880 - Posted: 06.24.2010

By Jocelyn Kaiser Two large studies of schizophrenia patients have yielded the most convincing evidence yet that the disease can be caused by mistakes in genes. The researchers linked a much higher risk for schizophrenia to three chromosomal regions that are missing chunks of DNA. Although only a tiny fraction of patients carried these particular glitches, similar errors may help explain other cases of the disease. Schizophrenia is a severe mental disorder involving hallucinations and delusions that affects as many as 1 in 100 people; it often runs in families. So far, searches for common genes linked to schizophrenia have been unsuccessful. In March, however, researchers reported a new clue in Science: Schizophrenics are more likely than healthy people to have rare variations in gene copy number--that is, they have fewer or more copies of a gene than most other people. Many of these copy number changes occurred in only one individual or one family, however, and the study could not pin down the risks associated with a particular variant. Now the largest studies to date have bolstered the case for copy number variants. The U.S.–European International Schizophrenia Consortium, which compared copy numbers in about 3400 patients and 3200 controls, found that large chunks of extra or missing DNA were 15% more common in people with the disease compared with controls. Moreover, the researchers found a much greater risk for patients with DNA deletions in two specific locations on chromosome 1 and chromosome 15. A second study by deCODE Genetics in Reykjavik, Iceland, and a European consortium known as SGENE, which involved about 4700 schizophrenia cases and 41,200 controls, pinpointed these same two variants and an additional one on chromosome 15. Both papers are published online today in Nature. © 2008 American Association for the Advancement of Science.

Keyword: Schizophrenia; Genes & Behavior
Link ID: 11879 - Posted: 06.24.2010

By Steve Mitchell While we snooze, scientists think, our brains are busy forming new memories by replaying the events of the day. But aging may rob us of this process and set us up for having "senior moments." A new study has found that older rats seem to replay previous events less and, as a result, have more trouble remembering than younger animals. How our brains form memories is not entirely understood, but sleep may be vital. The hippocampus region of our brain seems to rerun experiences we had while awake, a process that scientists believe helps cement memories. A team led by neuroscientist Carol Barnes at the University of Arizona, Tucson, noticed that older rats--just like older people--sometimes have trouble remembering. Could those memory problems be due to a decline in the brain's replay during sleep? In the study, 11 young and 11 older rats learned the locations of food rewards in several mazes. Meanwhile, researchers recorded the electrical activity of their hippocampi with probes inserted into their brains. That night, while the rats slept, the researchers monitored the hippocampus activity again. The young rats showed roughly the same kind of hippocampus activity in their sleep as they did when they were navigating the mazes; apparently, they were replaying the events. But the older rats did not, indicating that the replay process was impaired, the researchers report in the 30 July issue of The Journal of Neuroscience. Further experiments showed that the whippersnappers had a sharper memory; they were faster and more accurate than the older animals in remembering where a hidden platform was located while swimming in a tank of water. © 2008 American Association for the Advancement of Science

Keyword: Sleep; Alzheimers
Link ID: 11878 - Posted: 06.24.2010

ESSAY By JAMES POTASH, M.D. New research lends more credence than ever to the concept of "comfort foods." (AP Photo)Some patients with depression will eat a pint of Ben and Jerry's ice cream at night before they go to bed. They feel comforted -- at least briefly -- by the high-calorie treat. Of course, it doesn't take too many nights of this before the pounds start piling up. New research published in the journal Nature Neuroscience this month may shed some light on the biological relationship between depression and appetite. While it does not show that Ben and Jerry's is an antidepressant, it does suggest that a brain chemical, that motivates the consumption of the ice cream, may be. The chemical is called ghrelin, and it is naturally produced in the brain and the stomach. It was only discovered in 1999 by researchers who named it based on the Proto-Indo-European word root "ghre" for "grow," referring to its ability to stimulate growth hormone. But it turns out to be the most potent appetite stimulant known. © 2008 ABCNews Internet Ventures

Keyword: Depression; Obesity
Link ID: 11877 - Posted: 06.24.2010

Scientists have found further evidence that taking commonly used cholesterol- lowering statins may protect against dementia and memory loss. The study, published in Neurology, found that statins - normally taken to reduce heart disease risk - may cut the risk of dementia by half. The five-year project examined 1,674 Mexican Americans aged 60 and over at heightened risk of dementia. The Alzheimer's Research Trust said the research is "encouraging". A quarter of the patients took a statin, and in total 130 went on to develop dementia. Once the researchers had taken account of other risk factors, including education, smoking, and diabetes, they calculated that those who took statins had an approximately 50% lower risk of developing dementia. The study comes hot on the heels of separate research which suggests that drugs to reduce blood pressure can also cut the risk of dementia. It is estimated that 4 million people in England and Wales alone currently take statins. Lead researcher Professor Mary Haan, of the University of Michigan, said: "The bottom line is that if a person takes statins over a course of about five to seven years, it reduces the risk of dementia by half, and that's a really big change." Statins help to reduce the risk of heart disease by lowering levels of cholesterol which clog up the blood vessels. It is thought that a poor supply of blood to the brain may be one factor which promotes the development of dementia. Therefore, if statins help keep the blood vessels healthy, and blood flowing freely to the brain, they may help protect against the disease. (C)BBC

Keyword: Alzheimers
Link ID: 11876 - Posted: 07.29.2008

JoNel Aleccia The number of Americans who died at home after ingesting toxic combinations of prescription medications, alcohol and street drugs such as marijuana exploded by more than 3,000 percent during the past two decades, new research shows. The spike is a serious sign that many U.S. patients are having trouble coping with the shorter hospital stays, less clinical oversight and more powerful medications that have become hallmarks of medical care in recent years, said David P. Phillips, a sociologist at the University of California at San Diego. “In the old days, you’d stay in the hospital three times as long,” said Phillips, whose team analyzed more than 50 million U.S. death certificates from 1983 to 2004. More procedures are now performed on an outpatient basis and busy doctors are apt to prescribe more drugs with less follow-up, the researchers theorized. During the study period, the number of per capita prescriptions issued jumped by nearly 74 percent, researchers noted. “In an effort to save money, more and more of the burden of quality control has been placed on the shoulders of the patient,” he said. © 2008 MSNBC Interactive

Keyword: Drug Abuse
Link ID: 11875 - Posted: 06.24.2010

Patients with early Alzheimer's disease who exercised regularly saw less deterioration in the areas of the brain that control memory, according to a study released Sunday at a conference in Chicago. Magnetic resonance imaging (MRI) studies showed that exercise positively affected the hippocampus region of patients' brains, an area important for both memory and balance. In Alzheimer's, the hippocampus is one of the first parts of the brain to suffer damage. Exercise and physical fitness have been shown to slow down age-related brain cell death in healthy older adults, and earlier this month a preliminary study was published showing that exercise may help slow brain shrinkage in people with early Alzheimer's disease. Now, researchers at the University of Kansas Medical Center in Kansas City have used MRI and other neuroimaging tools to analyze how exercise affects the brains of those with early Alzheimer's. The study, released at the 2008 International Conference on Alzheimer's Disease (ICAD) in Chicago, found that patients with early Alzheimer's had a "significant relationship" between the size of key brain areas associated with memory and fitness, unlike healthy older adults. © The Canadian Press, 2008

Keyword: Alzheimers
Link ID: 11874 - Posted: 06.24.2010

By Adina Roskies and Walter Sinnott-Armstrong Cognitive science and moral philosophy might seem like strange bedfellows, but in the past decade they have become partners. In a recent issue of Cognition, the Harvard University psychologist Joshua Greene and colleagues extend this trend. Their experiment utilizes conventional behavioral methods, but it was designed to test a hypothesis stemming from previous fMRI investigations into the neural bases of moral judgments (see here and here). In their study Greene et al. give subjects difficult moral dilemmas in which one alternative leads to better consequences (such as more lives saved) but also violates an intuitive moral restriction (it requires a person to directly or intentionally cause harm to someone else). For example, in the “crying baby” dilemma subjects must judge whether it is wrong to smother their own baby in order to save a large group of people that includes the baby. In this scenario, which was also used by the television show M.A.S.H., enemy soldiers will hear the baby cry unless it is smothered. Sixty percent of people choose to smother the baby in order to save more lives. A judgment that it is appropriate to save the most lives, even if it requires you to suffocate a child, is labeled “utilitarian” by Greene et al., whereas a judgment that it is not appropriate is called “deontological.” These names pay homage to traditional moral philosophies. Based on previous fMRI studies, Greene proposes a dual-process model of moral judgments. This model makes two central claims. First, when subjects form deontological judgments, emotional processes are said to override controlled cognitive processes. © 1996-2008 Scientific American Inc.

Keyword: Emotions
Link ID: 11873 - Posted: 06.24.2010

By Rachel Zelkowitz Nine beers in one night could put even a seasoned drinker under the table. But the pen-tailed tree shrew in Malaysia consumes the equivalent of that in alcoholic nectar several nights a week, researchers have discovered, and six other species of animals there consume smaller amounts of alcohol as well. Unlike humans, the animals seem to suffer no ill effects from their habit. How they have evolved to tolerate alcohol could teach us something about the origins of human alcohol consumption and abuse, researchers say. The pen-tailed tree shrew (Ptilocercus lowii) is a small, ratlike animal that inhabits the jungles of Southeast Asia. It feeds on the nectar of an ever-flowering plant, the bertam palm, which is a primary food source for many other species as well, says Frank Wiens of the University of Bayreuth in Germany. Wiens was observing tree shrews feed in the Malaysian jungle when he noticed an oddly familiar odor: "The palms smelled like a brewery," he says. Wiens realized that some of the animals might be consuming huge amounts of alcohol, which prompted him and colleagues to spend more than 3 years in the field studying the ecology of the bertam palm. Yeast cells in the palm's flowers ferment its nectar, they discovered, which can contain up to 3.8% alcohol--among the highest concentrations ever found in natural foods. The researchers observed seven mammalian species feeding on the nectar. The pen-tailed tree shrews guzzled the stuff longer than they did any other food source, for an average of 138 minutes per night, in the process helping to pollinate the plants. © 2008 American Association for the Advancement of Science

Keyword: Drug Abuse; Evolution
Link ID: 11872 - Posted: 06.24.2010

Susan T. Fiske Most people think they're less biased than average. But just as we can't all be better than average, we can't all be less prejudiced than average. Although the message—and the success so far—of Barack Obama's presidential campaign suggests an America that is moving past traditional racial divisions and prejudices, it's probably safe to assume that all of us harbor more biases than we think. Science suggests that most of us don't even know the half of it. A 20-year eruption of research from the field of "social neuroscience" reveals exactly how automatically and unconsciously prejudice operates. As members of a society with egalitarian ideals, most Americans have good intentions. But new research suggests our brains and our impulses all too often betray us. That's the bad news. But here's the good news: More recent research shows that our prejudices are not inevitable; they are actually quite malleable, shaped by an ever-changing mix of cultural beliefs and social circumstances. While we may be hardwired to harbor prejudices against those who seem different or unfamiliar to us, it's possible to override our worst impulses and reduce these prejudices. Doing so requires more than just good intentions; it requires broad social efforts to challenge stereotypes and get people to work together across group lines. But a vital first step is learning about the biological and psychological roots of prejudice. Here's the first thing to understand: Modern prejudice is not your grandparents' prejudice.

Keyword: Emotions
Link ID: 11871 - Posted: 06.24.2010

Children carrying the first gene that has been clearly linked to obesity find it harder than others to tell when they are full, London-based researchers say. They studied over 3,000 children to see whether the FTO gene impacts on the ability to burn calories or appetite. The researchers found those with copies of the gene's risky variant were less likely to have their appetite "switched off" when they should be full. The study is published in the Journal of Clinical Endocrinology & Metabolism. FTO is the first common gene to be linked to obesity in Caucasian populations. The researchers, from University College London and the Institute of Psychiatry, King's College London, set out to learn more about the way the gene works. They tested whether children aged eight to 11 carrying the higher risk gene variation had an altered appetite through height, weight and waist circumference measurements, and a questionnaire which asked parents about their child's eating habits. They found that children with the higher risk version of the gene tended to overeat and to struggle to recognise when they were full. The effect of the gene on appetite was the same regardless of age, sex, socio-economic background and body mass index. (C)BBC

Keyword: Obesity; Genes & Behavior
Link ID: 11870 - Posted: 07.28.2008

A drug used to lower blood pressure could prevent or delay thousands of Alzheimer's cases, US research has suggested. People taking angiotensin receptor blockers were up to 40% less likely to develop dementia than those taking other blood pressure drugs. And patients already suffering from dementia were less likely to get worse. The number of people in the UK with dementia is expected to soar to 1.7 million over the next two decades. This could mean an enormous extra burden for families and the taxpayer, but the Boston University School of Medicine research, presented at a conference in Chicago, suggests there could be ways to prevent it. High blood pressure over long periods can lead to damaged blood vessels, and is known to increase the risk of not only strokes and heart disease, but dementia as well. Some types of dementia are directly related to the condition of the arteries supplying the brain, but blood pressure is also thought to play a role in Alzheimer's disease, which is linked to the appearance of protein deposits in brain tissue. However, the reasons for this are not clear. The research looked at records of approximately six million people treated for high blood pressure between 2001 and 2006. Those who took angiotensin receptor blockers (ARBs) were less likely, over that period, to be diagnosed with dementia compared with those on other blood pressure medication such as ACE inhibitors. (C)BBC

Keyword: Alzheimers
Link ID: 11869 - Posted: 07.28.2008

Michael Marshall Dementia is twice as common in low-income countries as previously thought, because the standard technique for diagnosing it is not suited to those countries. The finding comes from a study involving nearly 15,000 participants. Previous studies indicated that dementia rates are much lower in developing countries. A comprehensive review suggested that it was half as common, possibly even less. The new study shows much smaller differences. The 10/66 Dementia Research Group, led by Martin Prince from King's College London, UK, surveyed people over the age of 65 in seven low- and middle-income countries, including China, India and Mexico. They used their in-house diagnostic kit, the "10/66 algorithm", which they argue is more sensitive to cultural differences than the standard method used – as outlined in the latest Diagnostic and Statistical Manual of Mental Disorders (DSM). The 10/66 method gave dementia rates that were about double those from the manual. Prince told New Scientist that the DSM was designed for developed countries, where education standards are high. It struggles to pick up impairments among people with little education. © Copyright Reed Business Information Ltd.

Keyword: Alzheimers
Link ID: 11868 - Posted: 06.24.2010

By Richard Gray, Science Correspondent When it comes to memory it is clear that men and women are simply not on the same wavelength. While men may fail to match a woman's ability to remember the date of an anniversary, they are better at storing a seemingly endless cache of facts and figures. Scientists believe they have now uncovered the reason for this difference between the sexes – they make the memories in different ways. Researchers at the Institute of Psychiatry, King's College London, have found that males use different genes from females when making the new connections in the brain that are needed to create long-term memories. They believe this might explain why men are far better at remembering "tactical" memories, such as travel directions and trivia, while women form more "emotional" memories such as birthdays, wedding anniversaries and details about the world around them. Professor Peter Giese, who led the Medical Research Council- funded research , said they had identified two genes that seemed to be important for learning and making memories in males but not females. © Copyright of Telegraph Media Group Limited 2008

Keyword: Learning & Memory; Sexual Behavior
Link ID: 11866 - Posted: 06.24.2010

Justin Mullins Electronic canes for the blind are designed to detect nearby objects and provide a stereo audio signal that informs a person of the location of obstacles. But they do not distinguish between stationary and moving objects. A pair of spectacles fitted with a camera and accelerometers that detect movement can, however. They are connected to a computer that spots any obstacles in the field of view and works out which are moving. The specs provide audio signals to the wearer to let them know what's happening around them, and which objects are moving, so they can navigate without bumps. The system was dreamed up by electronics company Philips. Interfacing with the brain to control devices such as wheelchairs, robots and prosthetic devices has great potential. Monkeys have shown impressive ability to control robot limbs using brain implants, but must "rewire" their brains through training to do it. It would make things easier to use the signals naturally used for hand-eye coordination. But nobody has been able to figure out how the part of the brain responsible for hand-eye coordination, the primary motor cortex, does its job. Even recording the activity of this brain region has proved difficult. © Copyright Reed Business Information Ltd.

Keyword: Vision; Robotics
Link ID: 11865 - Posted: 06.24.2010

Phil Hogan Now where was I? Ah, yes. I'm reading a book. It's about memory but of course I've already lost my thread. Neurons are involved, I know that much - involved, that is, not just in remembering what you've just read, for example, but also in the amazing way things can go in one ear and out of the other. I must try harder. I'm on chapter five but I'm also on a plane heading for San Francisco, where I have an appointment to see a memory expert at the university. After that, I'm whizzing off to New York to watch the 2008 US Memory Championships, where I'm expecting to get some tips on how to remember all the names in a telephone directory. A trip down memory lane, then, an odyssey of self-improvement. My powers of recall are less than astonishing these days. For weeks, I've been racking my so-called brain, trying to put a name to the little town in southern Italy, on the cliff tops above Ischia and Capri. In 1983, my wife and I got off an island ferry there, stopped for a beer, then took a bus down the coast. It's a nice place. Odysseus (speaking of odysseys) stopped to listen to the Sirens there. Not Amalfi, not Positano. The other one. Full of Brits. You probably know it. I know it. But what is it called? Every now and then, I try to conjure it out of the remembered glare and bustle and sea and sky of that summer. I can see it but I'm damned if I can say it. I'm determined not to look it up. I keep thinking it's bound to come back but it hasn't. © Guardian News and Media Limited 2008

Keyword: Learning & Memory; Alzheimers
Link ID: 11864 - Posted: 06.24.2010

Pain is a simple enough concept to grasp. You stub your toe, shout, perhaps utter a few expletives, rub it better and it eventually fades. But neuroscientists are realising that pain is much more complex than anyone thought possible, comprising not just physical sensations, but emotional ones too. Pioneering studies are providing insights into why some people experience debilitating chronic pain long after an injury has healed, as well as why some are more prone to pain than others, and why certain people never recover from bereavement. “Pain is much more than mere sensation. The psychological component is at least as important as the physiological processes giving rise to it,” says Dr Jonathan Brooks, a scientist at the Centre for Functional Magnetic Resonance Imaging of the Brain, at Oxford University. His research centre scans the brains of people with chronic pain and compares them with those of healthy people. While most pain goes away as an injury gets better, sometimes it remains for months or even years, long outlasting its original purpose. Chronic physical pain is debilitating and can cause disability, depression and post-traumatic stress disorder. It is also very common. A group from the University of Washington reported in the journal Archives of Surgery earlier this year that 63 per cent of patients who had sustained serious trauma still had injury-related pain a year later. It was most common in the 35-44 age group and in women, and least common in those with a college education. Copyright 2008 Times Newspapers Ltd.

Keyword: Pain & Touch
Link ID: 11863 - Posted: 06.24.2010

In a note-worthy study of the human brain, scientists have discovered that a large expanse of a musician's brain "shuts off" while improvising music. Jazz and science would seem to make strange bedfellows, but both form the basis of Charles Limb's career. On the one hand, he's a faculty member at the Peabody Conservatory of Music at Johns Hopkins University in Baltimore, MD, and a life-long jazz musician. On the other, he's also a doctor and assistant professor in Johns Hopkins School of Medicine's Department of Otolaryngology-Head & Neck Surgery. "The thing I love about jazz is that in many ways it's so unscientific," says Limb. "You know, when you listen to jazz, what you realize is that these musicians, they really live by breaking the rules, by sort of rejecting excessive control over what they're going to do. … And I think for a scientist who sort of thrives on controlling variables and really having a clear sense of order in all things, the freedom that really characterizes jazz — it's an unusual mix." That mix came front and center when Limb decided he wanted to use science to study jazz. In particular, he was interested in the neurological basis of improvisation. "The mental state, the creative state that you're in when you're improvising is entirely different than when you're playing something that you've learned by memory," he says. "As a jazz musician for most of my life, I've always wondered what takes place inside my head when I'm actually improvising something." © ScienCentral, 2000-2008

Keyword: Hearing
Link ID: 11862 - Posted: 06.24.2010