Hunger is the downfall of many dieters, causing them to reach for the closest, but not necessarily the healthiest, foods. What they end up eating may taste different, too. New findings suggest that hunger affects how food tastes by making peckish people more sensitive to sweetness and saltiness. A number of factors, including obesity, oral hygiene, drinking and smoking, have been shown to alter a person’s ability to taste. In the new work, published today in the journal BMC Neuroscience, Yuriy P. Zverev of the University of Malawi investigated how overnight fasting affected the tastebuds of healthy males who neither smoked nor drank. After eating a set meal for dinner, the subjects skipped breakfast and were subsequently tested on their ability to taste salty, sweet and bitter solutions of varying concentrations. The participants returned later in the day, about an hour after eating lunch, and repeated the blind taste tests. When hungry, the men detected lower concentrations of sugar and salt than they did after a meal, but their ability to detect bitter compounds remained unchanged. © 1996-2004 Scientific American, Inc.

Keyword: Chemical Senses (Smell & Taste)
Link ID: 5026 - Posted: 06.24.2010

Killing the eldest males will protect lion populations. MICHAEL HOPKIN Researchers have developed a rule of thumb that they hope could save lion populations from declining at the hands of trophy-hunters. They are urging hunters to kill only males with dark noses. A lion's nose is speckled with dark pigment, and these freckles become more pronounced as the lion ages, explains Craig Packer of the University of Minnesota in Saint Paul, who led the study. Removing only the old males whose noses are at least 50% dappled with pigment would minimize the disruption to lion prides, his team found1. This gives cubs a better chance of survival. (C) Nature News Service / Macmillan Magazines Ltd 2004

Keyword: Sexual Behavior; Evolution
Link ID: 5025 - Posted: 02.23.2004

[Subscription required] ANTHONY P. MONACO The Birth of the Mind: How a Tiny Number of Genes Creates the Complexities of Human Thought by Gary Marcus If the mind can be explained from the workings of the brain, and the brain develops by direction from our genes, then presumably the mind can be explained from our genetic make-up. But how can only 30,000 genes make a brain with billions of neurons and encode the particular aspects of cognition that make us human? The Birth of the Mind tries to unravel this complex problem by first explaining what we know about each component of the argument: the mind, the brain, our genes and the environment. The breadth of examples used to achieve this is impressive, encompassing 40 different organisms (from bacteria to chimpanzees), 30 different genes and 20 different brain regions. The author, Gary Marcus, spends much of his efforts building up the reader's knowledge base. It is difficult to make an argument that involves such diverse disciplines as evolution, genetics, gene expression, cell biology, neurobiology and psychology without teaching the reader the bare essentials. Marcus does particularly well to make the relevant issues in these areas understandable to the lay reader, and does an even better job of dispelling the myths that impede the way we think about genes and their role in making brains, and hence minds. © 2004 Nature Publishing Group

Keyword: Development of the Brain; Genes & Behavior
Link ID: 5024 - Posted: 06.24.2010

A researcher wants to help you measure your AQ By Steven Johnson THESE DAYS, NEW THEORIES about how the human brain works are everywhere. Whether it's a magazine feature on the brain's evolutionary history, or a book purporting to reveal the origins of consciousness, or a newspaper report on the discovery of a new neurological center ("This is where a craving for chocolate comes from!"), there's no lack of fascinating hypotheses about how we, as a species, are wired. But modern brain science can also be directed toward more idiosyncratic and immediately useful ends. Much as an art historian can help us discern hitherto unnoticed qualities in a painting, today's neuroscientists are bridging the gap between the physical reality of our brains and our everyday mental lives. They're making us aware of ingrained reflexes and patterns we didn't realize were affecting us intimately. Cutting-edge neuroscience can teach us not only "how the mind works," but how our own minds work. Take mindreading skills, for example. Although it may suggest something from the Psychic Friends Network, "mindreading" is a term used by some scientists to describe the complex yet taken-for-granted talent most people have for detecting the inner emotional states of others. Whenever we converse, our spoken dialogue is accompanied by a second, lightning-fast discourse of small gestures, vocal intonations, fleeting smiles, arched eyebrows, and other signals that help us understand one another. © Copyright 2004 Globe Newspaper Company.

Keyword: Autism
Link ID: 5023 - Posted: 06.24.2010

A relatively limited form of throat surgery may be more effective at correcting a common sleep disorder than more invasive alternatives. Researchers from Taipei's Chang Gung Memorial Hospital achieved an 82% success rate when they operated on sleep apnoea patients. The research, which was only based on 55 patients, is published in the journal Archives of Otolaryngology. However, UK experts have expressed doubts about the study's validity. Sleep apnoea causes snoring and interruptions in breathing. This forces the sufferer to wake up in order to start breathing again. Sometimes this can happen up to 100 times a night. Standard surgery for severe sleep apnoea involves removing some of the tissue in the throat to widen the airway. However, it usually only works in about half of cases. The new technique - called uvulopalatal flap surgery - removes fatty tissues, soft glands and the tonsils to increase airway space, but spares muscle tissue. Patients who had the surgery said they snored less, were less sleepy during the day and had higher oxygen levels in their blood. (C) BBC

Keyword: Sleep
Link ID: 5022 - Posted: 02.22.2004

By Dr David Whitehouse, BBC News Online science editor Exposure to low-level magnetic fields could be harmful, say US scientists. Rats exposed to magnetic fields similar to those humans encounter developed damage to the DNA in their brain cells. Professor Henry Lai, of Washington University, said that people should be prudent in their use of electrical devices held close to the head. The peer-reviewed study is published in Environmental Health Perspectives, a journal of the US National Institute of Environmental Sciences. The researchers discovered that rats exposed to a weak magnetic field oscillating 60 times per second for 24 hours showed DNA damage to their brain cells. Rats exposed for 48 hours showed even more damage. They also say that the exposure resulted in an increase in brain cell "apoptosis" or "cell suicide" - a process in which the cell self-destructs because it cannot repair itself. But what are the implications for people and the magnetic fields most of us encounter in our daily lives? (C) BBC

Keyword: Miscellaneous
Link ID: 5021 - Posted: 02.22.2004

By GINA KOLATA SHE charges that his group is like the Taliban. He claims that her group's dangerous message has "spread like a virus across North America, Europe and elsewhere." The issue inspiring such invectives? Not religion, but diets. The latest spat is between Veronica Atkins, widow of Robert Atkins, the doctor who promoted a low-carbohydrate diet, heavy on the meats, and the Physicians Committee for Responsible Medicine, a group that advocates vegetarianism. Copyright 2004 The New York Times Company

Keyword: Obesity; Animal Rights
Link ID: 5020 - Posted: 02.22.2004

By ABRAHAM VERGHESE In America, we have always taken it as an article of faith that we ''battle'' cancer; we attack it with knives, we poison it with chemotherapy or we blast it with radiation. If we are fortunate, we ''beat'' the cancer. If not, we are posthumously praised for having ''succumbed after a long battle.'' If you accept the war metaphor (and not everyone does), then a diagnosis of cancer becomes a call to arms, an induction into an army, and it goes without saying that in such a war, optimism is essential. Memoirs of cancer survivors and the Web sites of some cancer centers state this as a creed: a ''positive attitude'' influences survival. But a recent Australian study of 204 people with lung cancer found that those who were optimistic before and after treatment did not live longer; they did not fare better (or worse) than their less hopeful counterparts. Earlier studies have examined cancer patients' helplessness or depression or pessimism. The results are a mixed bag, with some studies showing that a negative attitude hurts survival and others showing no relation between one's temperament and one's survival. What makes the Australian effort different is that it focused rigorously on a fairly large group of patients with a single type and stage of cancer, and it used a well-accepted method for assessing optimism. The study followed patients for five years. By taking these steps, the Australians overcame many (though not all) of their predecessors' methodological weaknesses. (Ideally, they would have examined whether optimism detected before a diagnosis of cancer was ever made -- optimism as a character trait, rather than as an attitude after diagnosis -- correlated with outcome.) Optimism, it seems, is overrated -- at least when it comes to this particular form of cancer. Biology (and the availability of effective treatment) determines fate. Copyright 2004 The New York Times Company

Keyword: Neuroimmunology; Stress
Link ID: 5019 - Posted: 02.22.2004

Liberal Democrat MP Dr Evan Harris has called for an independent inquiry into research that led to links being made between autism and the MMR vaccine. The medical journal that featured the study has said that, with hindsight, it would not have published the research. Richard Horton, editor of the Lancet, told the BBC the researchers had a "fatal conflict of interest". But Dr Andrew Wakefield, the researcher at the centre of the study, has rejected the journal's claims. The paper, published six years ago, prompted many parents to reject the three-in-one jab, even though most experts say it is safe. The Lancet launched an investigation into the way the study was carried out after it received an "allegation of research misconduct" from the Sunday Times. The allegations do not cover the actual findings of the study. (C) BBC

Keyword: Autism
Link ID: 5018 - Posted: 02.21.2004

Leopards may never change their spots, but some mammals can adjust the sex of their offspring, according to a study by biologists. Experts from Edinburgh and Oxford Universities have found that some species are capable of influencing whether to produce sons or daughters. Species examined for the study included zebras, gazelles, deer and goats. The full results of the research are due to be published in the American Naturalist journal next week. It will explain in full why some species are capable of producing sons when conditions are conducive to childbearing, and daughters at less favourable times. Although the characteristic is well known in bees and wasps, the study is the first to offer conclusive proof of the trait in a range of ungulates - herbivorous mammals with hooved feet. (C)BBC

Keyword: Sexual Behavior; Evolution
Link ID: 5017 - Posted: 02.21.2004

Bruce Bower Seniors interested in pumping up their brains and maintaining an attentive edge might consider taking this inexpensive prescription: Go for a walk every 2 or 3 days. Don't sweat it, but make an effort. Limit each walk to between 10 and 45 minutes. That's the conclusion, at any rate, of two new studies that demonstrate for the first time in people that physical fitness, whether achieved on one's own or through a brief aerobic-training course, induces brain changes associated with improved performance on an attention-taxing task. "Even moderate cardiovascular activity of the sort that is within reach of most healthy older adults results in improved neural functioning and may help to extend or enhance independent living," says neuroscientist Arthur F. Kramer of the University of Illinois at Urbana-Champaign. Kramer directed the new studies with his colleague Stanley J. Colcombe. Copyright ©2004 Science Service.

Keyword: Alzheimers
Link ID: 5016 - Posted: 06.24.2010

Taking cocaine could cause irreversible brain damage, scientists from Edinburgh University have warned. Tests on genetically modified mice showed that cocaine inhibited the brain by destroying a key protein responsible for learning and memory. Abusing the highly addictive drug can lead to long-term memory loss and learning difficulties, say experts. One of the scientists behind the study said prolonged abuse could even affect long-term career prospects. Scientists have already shown that cocaine gives users a "high" by stimulating the area of the brain known as the striatum and leads to a craving for more of the Class A drug. Now, researchers at the University of Edinburgh, the Cambridgeshire-based Wellcome Trust Sanger Institute, and US scientists have shown that levels of the protein PSD-95 - directly linked to learning and long-term memory - dropped by half when exposed to cocaine in laboratory tests. (C) BBC

Keyword: Drug Abuse
Link ID: 5015 - Posted: 02.20.2004

By SANDRA BLAKESLEE A type of self-renewing cell found in the adult human brain may have the potential to repair brain damage or disease, scientists reported yesterday. The cells, neural stem cells, have been known about for some time. But their function has been a mystery. Researchers theorized that the cells, as in rats and monkeys, generated new neurons that migrated to olfactory regions, helping maintain the sense of smell. But the study, reported yesterday in Nature, indicates that in humans, the stem cells behave differently. They form ribbons that produce different types of brain cells, including neurons. The new neurons do not migrate to olfactory regions, and they are not involved in the human capacity for smell, the study found. Copyright 2004 The New York Times Company

Keyword: Stem Cells; Regeneration
Link ID: 5014 - Posted: 02.20.2004

Do canines have character? As this ScienCentral News video reports, according to one psychologist, personality testing is going to the dogs. Ask most dog owners, and you'll find no doubts that their canine companions have personalities. But many scientists have typically dismissed this idea. "Scientists have been very mixed in their response to the idea of animal personality," says Sam Gosling, a psychology professor at the University of Texas at Austin currently on sabbatical at the Center for Advanced Study in the Behavioral Sciences. "If somebody says 'Rover is friendly,' what scientists believe, I think, is that we're learning more about the owner than we are learning about Rover, and therefore they think that such a description such as 'Rover is friendly' is not the correct type of information that a serious scientist should be using." © ScienCentral, 2000-2003.

Keyword: Evolution
Link ID: 5013 - Posted: 06.24.2010

People with a history of the digestive disorder celiac disease are three times more likely to develop schizophrenia than those without the disease, according to a report by Danish researchers and a researcher at the Johns Hopkins Bloomberg School of Public Health. The report is published in the February 21, 2004, edition of the British Medical Journal. Celiac disease is an autoimmune disorder that impairs the body's ability to digest the protein gluten, which is found in grains and many other foods. The condition can lead to diarrhea, weight loss and malnutrition. William W. Eaton, PhD, lead author of the report and interim chair of the Department of Mental Health at the School of Public Health, said, "For years, scientists have suspected a link between celiac disease and schizophrenia. Our research shows that the link is moderately strong." Dr. Eaton and his colleagues examined the records of 7,997 schizophrenic patients admitted to a Danish psychiatric facility for the first time between 1981 and 1998. Those records were compared to Denmark's national patient register to determine if the schizophrenic patients or their parents were previously treated for celiac disease. The researchers also looked for diagnosis of similar digestive disorders not previously associated with schizophrenia, which included dermatitis herpetiformis, Crohn's disease and ulcerative colitis. The researchers found a small number of schizophrenic patients were previously treated for celiac disease or had a parent treated for celiac disease. Both conditions are rare.

Keyword: Schizophrenia
Link ID: 5012 - Posted: 02.20.2004

Empathy lights up the same parts of the brain as personal injury. LAURA NELSON The ability to appreciate other people's agony is achieved by the same parts of the brain that we use to experience pain for ourselves. When we encounter a painful stimulus, such as an electric shock, signals travel from the site of the stimulus up to the brain. This is then translated into both a physical and an emotional response. Tania Singer, an imaging neuroscientist at University College London, and her colleagues performed an experiment to see whether any parts of this process happens in the brains of people who aren't experiencing the pain themselves, but are simply empathizing with someone who is. © Nature News Service / Macmillan Magazines Ltd 2004

Keyword: Pain & Touch; Emotions
Link ID: 5011 - Posted: 06.24.2010

Knowing our partner is in pain automatically triggers affective pain processing regions of our brains, according to new research by University College London (UCL) scientists. The study, published in the 20th February edition of the journal Science, asked whether empathizing with the pain of others involves the re-activation of the entire pain network underlying the processing of pain in our selves. The results suggest that empathy for pain of others only involves the affective, but not sensory component of our pain experience. The team, at UCL's Wellcome Department of Imaging Neuroscience, set out to find out what happens to our brains when we empathise with the feelings of others, how the brain understands how something feels for another human, and whether such empathetic responses are triggered rather automatically by the mere perception of someone else being in pain. The UCL team investigated pain-related empathy in 16 couples, under an assumption that couples are likely to feel empathy for each other. Brain activity in the woman was assessed while painful stimulation was applied to her or to her partner's right hand through an electrode attached to the back of the hand. Both hands were placed on a tilted board allowing the subject, with help of a mirror system, to see both hands. Behind this board was a large screen upon which flashes of different colours were presented. The colours indicated whether to expect painful or non painful stimulation. This procedure enabled to measure pain-related brain activation when pain was applied to the scanned subject (the 'pain matrix') as well as to her partner (empathy for pain).

Keyword: Pain & Touch; Emotions
Link ID: 5010 - Posted: 02.20.2004

Scientists hope they'll serve as brain repair kit Carl T. Hall, Chronicle Science Writer A mysterious type of stem cell found in the brain appears to be a possible wellspring of fresh nerve cells and, when something goes haywire, the starting point of a common form of tumor, scientists are reporting. The finding lays new ground for understanding the fundamental biology of stem cells in the adult brain. Scientists hope these cells and the signaling molecules that govern their fate might someday serve as a repair kit for treating brain injury, strokes or neurodegenerative diseases such as Parkinson's. The study resulted from a collaboration of neuroscientists and brain surgeons at UCSF Medical Center, led by Dr. Nader Sanai, a 26-year-old neurosurgery resident. Dr. Mitchel Berger, chair of neurosurgery, and stem- cell expert Arturo Alvarez-Buylla were senior authors. ©2004 San Francisco Chronicle

Keyword: Stem Cells
Link ID: 5009 - Posted: 06.24.2010

By MIREYA NAVARRO With typical bluntness Sue Johanson tells older men and women to get over body image: the "turkey neck," the "wear and tear," the hormonal deficiencies. But in her cheerful, no-nonsense style she adds that there are creams, patches and pills to help them, and if all else fails, that they can always kiss and cuddle. "You can still have a great deal of fun," she said recently in a rare speech before a United States audience, a group of sex-toy saleswomen at a conference in Las Vegas. Ms. Johanson, who won't reveal her age but looks like a 70-something grandmother who knits and makes sourdough biscuits (she does both), is having a lot of fun herself just talking about sex. Copyright 2004 The New York Times Company

Keyword: Sexual Behavior
Link ID: 5008 - Posted: 02.19.2004

By SAM LUBELL THE red curtain opens to reveal an intimidating auditorium. A bored audience stares back at you. One person in the crowd seems to be falling asleep; another coughs loudly and stretches his neck. You notice that your palms are sweaty. Your stomach is fluttering. You wonder whether you will pass out. But this is no ordinary panic attack: it is a virtual scene that was created to help people overcome anxiety about public speaking. This slice of virtual reality and other similarly stressful scenes are the work of a Georgia-based company called Virtually Better, which creates virtual environments with 3-D imaging software for use by psychologists, psychiatrists and researchers. A few years ago, the full impact of a bored audience could only be imagined by a patient with a therapist's help, or in some cases recreated at great cost with mockups and actors. But with recent advances in research and improvements in hardware and software, virtual reality has become a tool to help patients overcome fears and anxieties. Copyright 2004 The New York Times Company

Keyword: Emotions
Link ID: 5007 - Posted: 02.19.2004