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By MARY DUENWALD Every doctor recognizes them. The man who discovers a bruise on his thigh and becomes convinced that it is leukemia. The woman who examines her breasts so frequently that she makes them tender, then decides that the soreness means she has cancer. The man who has suffered from heartburn all his life but after reading about esophageal cancer has no question that he has it. They make frequent doctors' appointments, demand unnecessary tests and can drive their friends and relatives — not to mention their physicians — to distraction with a seemingly endless search for reassurance. By some estimates, they may be responsible for 10 to 20 percent of the nation's staggering annual health care costs. Yet how to deal with hypochondria, a disorder that afflicts one of every 20 Americans who visit doctors, has been one of the most stubborn puzzles in medicine. Where the patient sees physical illness, the doctor sees a psychological problem, and frustration rules on both sides of the examining room. Copyright 2004 The New York Times Company

Keyword: Miscellaneous
Link ID: 5211 - Posted: 06.24.2010

An estimated 19 million Americans experience depression in any given year. For many of them, anti-depressant medications help but don't offer a cure. As this ScienCentral news video reports, one researcher is looking into how adding exercise to the prescription might make those people feel better. Becky Sands, a 55-year-old personal financial advisor, has been battling depression since she was about 18 years old. "Something happened in my life, a situational thing, and I really crashed," she says. "After that, one thing lead to another, and I had my ups and downs ever since then." Sands tried medication in her mid-thirties, started feeling better, and went off the drugs. But her depression returned, and she went back on the medication. "I started taking it on a regular basis," she says. "Never forgot a dose but I still didn't feel right and I thought maybe I needed bigger doses. So I went back and the doctor gave me some more and some more and it still didn't make a difference." © ScienCentral, 2000-2004.

Keyword: Depression
Link ID: 5210 - Posted: 06.24.2010

Bats, along with other animals that employ echolocation, rely on their ears more than their eyes for orientation and navigation. The creatures send out signals and then listen to the echo bouncing off of an item. But just how the animals analyzed a spate of echoes coming off of the same object, such as a leafy tree, has eluded scientists. New research suggests that bats are skilled statisticians. They appear to perform a type of statistical analysis on the sum of all the acoustical reflections in order to make sense of their complex surroundings. When sonar emissions encounter an object, they form a characteristic signal that scientists call an impulse response (IR), which is essentially an acoustical picture. Simpler items result in straightforward IRs, whereas complex surfaces, such as foliage, lead to more chaotic ones. Lutz Wiegrebe of the Ludwig-Maximilians University in Munich and his colleagues tested the ability of lesser spear-nosed bats, Phyllostomus discolor (see image), to respond to computer-generated IRs for a variety of phantom objects. To do this, the researchers tweaked a statistical property known as roughness, which describes the amount of variation within the signal, and analyzed the bats’ reactions. © 1996-2004 Scientific American, Inc.

Keyword: Hearing
Link ID: 5209 - Posted: 06.24.2010

If you're going to move into someone's house and eat their children, it pays to be discrete. Predators that live in ant colonies, called myrmecophiles, get away with this because they smell, look, and behave just like ants. A new study shows how an Australian spider has reached new levels in this con game. Cosmophasis bitaeniata doesn't just smell like ant--it smells like home. Cosmophasis prey only on weaver ants (Oecophylla smaragdina). These tropical ants build nests by stitching leaves together with silk produced by their larvae. It is these tender larvae that the spider is after, explains evolutionary biologist Mark Elgar of the University of Melbourne in Australia. He and his colleague Rachel Allan observed how the spiders would enter weaver ant nests and somehow persuade workers to hand over the larvae. In previous studies they had discovered that the gullible ants are tricked into thinking the spider is an ant because it carries the same chemical cloak of "cuticular hydrocarbons," organic compounds that make up arthropods' characteristic body odor. Copyright © 2004 by the American Association for the Advancement of Science.

Keyword: Chemical Senses (Smell & Taste); Evolution
Link ID: 5208 - Posted: 06.24.2010

by D. Blake Woodside, M.D. Psychiatric Times The occurrence of eating disorders in men remains relatively rare but consistent. This is true despite recent research suggesting that male cases are far more numerous than had been previously thought. This brief article will comment on recent research findings in this area and describe their relevance to assessment and treatment. Two studies support the notion that eating disorders are more common than had previously been thought (Health Canada, 2003; Woodside et al., 2001). Woodside et al. (2001) reported on the results of a 10,000-person community epidemiologic study. Combining full- and partial-syndrome eating disorder cases for both men and women, the investigators showed an overall rate of three female cases for every one male case-a far cry from the typical 10:1 or 20:1 ratio found in most treatment settings. However, this study assessed only limited Axis II parameters and, as DSM-III-R diagnoses were generated from the data, the prevalence of binge-eating disorder could not be assessed. More recently, Health Canada (2003) released preliminary results from a national, face-to-face mental health survey of over 30,000 people performed in 2001 and 2002. This survey assessed for full-syndrome eating disorders and reported a ratio of male to female cases of approximately 1:5. This was somewhat higher than the findings from Woodside et al. (2001) but showed many more cases than might otherwise have been thought. The somewhat higher ratio in the Health Canada survey is almost certainly related to only full-syndrome cases that the Woodside et al. survey was too small to allow for. © 2004 Psychiatric Times. All rights reserved.

Keyword: Anorexia & Bulimia
Link ID: 5207 - Posted: 06.24.2010

by Malaz Boustani, M.D., M.P.H., and Lea Watson, M.D., M.P.H., Psychiatric Times Depression and dementia are common in older people and their association is very complex. Major and minor depression occur often in patients with dementia and can be associated with deterioration in cognitive functioning. Many clinicians have difficulty determining whether dementia, depression or both are the underlying disease for their patients' apathy, psychomotor retardation, concentration deficit and short-term memory impairment. Moreover, depression in dementia brings additional disability to patients who are demented and their caregivers, and a previous history of depression may be associated with an increased risk for the subsequent development of a dementing illness. In this article, we review the literature to address the interaction between depression and dementia and provide clinicians with information to improve the care of their patients who are demented. The aging of the U.S. population has been accompanied by a dramatic rise in the prevalence of both depression and dementia. Among community-dwelling older adults, 3% to 11% have dementia (Boustani et al., 2003) and 2% to 14% have depression (Beekman et al., 1999). In long-term care settings, 44% to 53% of the residents have dementia (Magaziner et al., 2000) and 9% to 30% have depression (Parmelee et al., 1989; Payne et al., 2002; Rovner et al., 1991; Watson et al., 2003). © 2004 Psychiatric Times. All rights reserved.

Keyword: Depression; Alzheimers
Link ID: 5206 - Posted: 06.24.2010

by Steffen Moritz, Ph.D., and Dieter Naber, Ph.D. Psychiatric Times There is broad consensus that cognitive deficits play a crucial role for both the pathogenesis and prognosis of schizophrenic psychoses. Cognitive disturbances often precede the first psychotic episode (Cannon et al., 2000) and persist over the different stages of the illness (Goldberg et al., 1993). It is important to note, however, that not all patients display neurocognitive disturbances and that contrary to early descriptions of the disorder (Kraepelin, 1893), recent cross-sectional and longitudinal studies suggest that schizophrenia is a neurodevelopmental disorder rather than a neurodegenerative one (Moritz et al., 2002a; Rund, 1998). A more recent tradition of research has shed light on the impact of neurocognitive disturbances on outcome and treatment-related variables. Meta-analysis research conducted indicated that cognitive deficits, especially impairments in the domains of memory and vigilance, are significant predictors of functional outcome (e.g., community outcome, social problem solving and skill acquisition) (Green, 1996; Green et al., 2000). In addition, neurocognitive functioning is related to insight (Rossell et al., 2003) and coping skills (Wilder-Willis et al., 2002). Further, there is increasing evidence that neurocognitive dysfunction may severely compromise medication compliance (Donohoe et al., 2001). © 2004 Psychiatric Times. All rights reserved.

Keyword: Schizophrenia
Link ID: 5205 - Posted: 06.24.2010

Nanoparticles cause brain damage in fish, according to a study of the toxicity of synthetic carbon molecules called "buckyballs". The soccer-ball-shaped molecules show great promise in nanotechnology. But the preliminary study raises the possibility that nanomaterials could cause significant environmental harm, although much further work is needed to establish the extent of this risk. Eva Oberdýrster of Southern Methodist University in Dallas, US, who led the study, found modest concentrations of buckyballs in water caused significant harm to two aquatic animals. Water fleas were killed by the addition of the tiny carbon balls, and fish showed up to a 17-fold increase in brain damage compared with unexposed animals. © Copyright Reed Business Information Ltd.

Keyword: Neurotoxins
Link ID: 5204 - Posted: 06.24.2010

But study confirms gender differences A new study that measures pain sensitivities among Whites and African-Americans suggests assessment procedures may be to blame for reported racial differences in the amount of pain experienced. Previous research and anecdotal clinical evidence have suggested that African-Americans tend to be more sensitive to pain than Whites, but the latest research study shows the two groups simply interpret standard pain rating scales differently. The new study also confirms earlier findings that women are more sensitive to pain than men. University of Calgary psychologist Dr. Tavis Campbell led the research project while at Duke University Medical Center in Durham, North Carolina. The results are being published in the April issue of the medical journal, The Journal of Pain. "Many pain medications are addictive and have unpleasant side effects, so it's important for physicians to be able to understand exactly how much pain their patients are experiencing," Campbell says. "This research supports well-established findings of slightly higher sensitivity to pain among women compared to men, but revealed no differences between Whites and African-Americans."

Keyword: Pain & Touch
Link ID: 5203 - Posted: 03.30.2004

NEW YORK (Reuters Health) - A single injection of cocaine appears to cause long-lasting craving in rats, which can be triggered by environmental cues, Italian researchers report. Dr. Roberto Ciccocioppo of at the University of Camerino and colleagues note that drug craving seems to be heightened by associated environmental cues. However, it was thought that this degree of dependence would require a long period of sustained drug use. To test this notion in rats previously trained to press a lever to obtain food pellets, the researchers paired environmental triggers with cocaine administration or control conditions. The results are described in an advance online article in the April issue of Nature Neuroscience.

Keyword: Drug Abuse
Link ID: 5202 - Posted: 03.30.2004

By Michael Stroh The sugary tang of dew-moist mulch. Steak spitting atop flaring coals. The laundry-fresh fragrance of a breezy April afternoon. Springtime aromas are easy enough to name - but almost impossible for scientists to explain. Why do certain substances smell the way they do? Long after researchers have unraveled many of the central mysteries of vision and the other four senses, they continue to be stumped by smell. Now scientists at Rockefeller University in New York have taken a small step toward solving the puzzle - not by determining what causes odor, but by showing what doesn't. In the April issue of Nature Neuroscience, scientists have for the first time cast doubt on a provocative theory of odor that has caused a major stink among olfactory researchers in recent years. Copyright © 2004, The Baltimore Sun

Keyword: Chemical Senses (Smell & Taste)
Link ID: 5201 - Posted: 06.24.2010

Carbenoxolone could aid verbal memory. HELEN R. PILCHER A drug derived from liquorice may boost brain function and slow age-related memory loss, research suggests. Carbenoxolone, which is traditionally used to soothe ulcers, improves mental functioning in healthy elderly men and cognitively impaired diabetic patients. The drug slows the sort of memory decline that occurs with normal ageing, says Jonathan Seckl from the University of Edinburgh, who led the study. It may, for example, help people to remember random words or recall what they did at the weekend. It could also slow the early stages of Alzheimer's disease, says Seckl, although this has yet to be tested. The early stages of dementia are indistinguishable from normal memory loss, so the drug could be given to stave off symptoms. Ten healthy elderly men, without any memory impairment, took carbenoxolone three times a day, the team report in Proceedings of the National Academy of Sciences1. Four weeks later, the subjects performed about 10% better on tests of verbal fluency (the ability to use and recall certain words) than nonmedicated controls. "Carbenoxolone boosts a specific verbal aspect of their memory," says Seckl. © Nature News Service / Macmillan Magazines Ltd 2004

Keyword: Learning & Memory
Link ID: 5200 - Posted: 06.24.2010

UC Berkeley experts offer advice on facing 'pitfalls' David Perlman, Chronicle Science Editor As controversies simmer across the country over teaching evolution, scientists at UC Berkeley are taking the offensive against the modern-day foes of Charles Darwin. Experts at the university's Museum of Paleontology have created a new Web site designed to offer beleaguered classroom teachers support and guidance through the often slippery attacks they can encounter teaching natural selection and other concepts. The site, at evolution.berkeley.edu, grew out of a conference that the museum hosted four years ago at which representatives from virtually every national scientific and education organization gathered to consider the growing pressures against evolution curricula. "We realized we really needed to put new resources into teachers' hands, and that's how the idea of using the Internet emerged," said David Lindberg, chairman of Berkeley's Department of Integrative Biology and former director of the paleontology museum. ©2004 San Francisco Chronicle

Keyword: Evolution
Link ID: 5199 - Posted: 06.24.2010

A group of scientists at The Scripps Research Institute, at the University of California in San Diego, and at the Oregon Hearing Research Center and Vollum Institute at Oregon Health & Science University have discovered a key molecule that is part of the machinery that mediates the sense of hearing. In a paper that will appear in an upcoming issue of the journal Nature, the team reports that a protein called cadherin 23 is part of a complex of proteins called "tip links" that are on hair cells in the inner ear. These hair cells are involved in the physiological process called mechanotransduction, a phenomenon in hearing in which physical cues (sound waves) are transduced into electrochemical signals and communicated to the brain. The tip link is believed to have a central function in the conversion of physical cues into electrochemical signals. "In humans, there are mutations in [the gene] cadherin 23 that cause deafness as well as Usher syndrome, the leading cause of deaf-blindness," says Associate Professor Ulrich Mueller, Ph.D., who is in the Department of Cell Biology at The Scripps Research Institute and is a member of Scripps Research's Institute for Childhood and Neglected Diseases.

Keyword: Hearing; Genes & Behavior
Link ID: 5198 - Posted: 03.30.2004

By SUSAN MORSE, Washington Post The next time you lock horns with your boss, your friend or your spouse and she tells you to leave emotion out of it, tell her that science proves that's a lousy idea. Block that emotion and all you're likely to produce are bad decisions. That heretical insight is at the heart of a revolution today in neuroscience and psychotherapy. The story, as told at the Psychotherapy Networker Symposium in Washington by Chicago-area marital therapist Brent Atkinson, starts with a 19th-century medical patient. Phineas Cage was a railway worker who in 1848 had a 3 1/2-foot iron rod blown through his skull in an explosion. To the surprise of doctors, he survived. Though he recovered physically with his intellectual faculties and motor skills intact, he was a changed man. He swore constantly, appeared fitful and abandoned plans as fast as he made them. Not until the 1990s -- when scientists produced computerized brain models based on photos of his skull -- was the reason for his character change confirmed: damage to the prefrontal cortex, a brain region that processes emotions governing social behavior.

Keyword: Emotions
Link ID: 5197 - Posted: 03.30.2004

Low levels of electrical activity in the brain may cause some people with epilepsy to have seizures, say experts. A team of international scientists carried out tests on 14 people with epilepsy and two without. They found that activity in the outer part of the brain slowed significantly when those with epilepsy were asleep. Writing in the Proceedings of the National Academy of Sciences, they said it may explain why many have seizures after falling asleep. Doctors have known for many years that sleep can trigger epileptic seizures. However, they have been unable to explain exactly why this happens. Previous studies have suggested it may be linked to very slow electrical activity in the brain. However, scientists have been unable to confirm this theory, largely because they were unable to detect very slow brain waves using conventional machines. (C)BBC

Keyword: Epilepsy
Link ID: 5196 - Posted: 03.28.2004

By D.T. MAX Janet Skarbek is 36 years old and lives in Cinnaminson, N.J. She is the author of ''Planning Your Future: A Guide for Professional Women,'' a book about managing the unknown. It was published in 2001 by the Professional Women's Institute, a small networking and support organization that Skarbek and three other women jointly ran out of their homes. ''Planning Your Future'' presents a world where exemplary order and control are possible. It urges working women to get ahead by thinking ahead: choosing a career with their children in mind, timing pregnancies so as not to lose traction at work. It tells them to fend for themselves in a society they may sometimes perceive as unsympathetic to their needs. Skarbek herself turned down a plum corporate job for the sake of her two kids. ''I knew that I wasn't willing to work the hours that a vice president of a Fortune 500 company would require to get the job done right,'' she said. Skarbek resembles Lewis Carroll's Alice -- the same short stature, broad forehead, straight, long hair and grown-up gaze, as well as the same touching, plucky personality. And like Alice, she, too, was about to fall down a rabbit hole. On January 2000, a friend of Skarbek's named Carrie Mahan became ill. One evening, Mahan, 29, went with her boyfriend to a party and came home unusually tired. The next morning she started hearing songs in her head and had trouble using her key to unlock her car door. At an emergency room in Philadelphia, doctors gave her medicine and suggested rest. But she was back the next day, complaining of anxiety, nausea and hallucinations. She was admitted, then transferred to the University of Pennsylvania Medical Center. Things got worse quickly. She faded in and out and began to suffer body twitches called myoclonus jerks. Soon she fell into a coma and was put on life support. About a month later, on Feb. 24, 2000, she was allowed to die. Copyright 2004 The New York Times Company |

Keyword: Prions
Link ID: 5195 - Posted: 03.28.2004

By GINA KOLATA YOU might think if questions were raised about whether antidepressant drugs can make patients suicidal during the first few weeks of treatment, that scientists would turn to animal testing for further investigation. After all, suicides are rare enough that there are no firm human data on whether the drugs can cause them. But you can do experiments with animals - examining their brains, giving them high doses of drugs - that you could never do with people. That might seem like a reasonable course of action, especially after the Food and Drug Administration announced last week that it was so concerned about a possible, though very slight, suicide risk that it wants antidepressant drugs to carry warnings on their labels. But it turns out that animal experiments are not an option. Copyright 2004 The New York Times Company

Keyword: Depression; Animal Rights
Link ID: 5194 - Posted: 03.28.2004

People are needlessly suffering from headaches because they are not getting access to treatment, say experts. Headache disorders must be given higher priority by health providers around the world, say campaigners launching a new global initiative. The Lifting the Burden campaign says better education among health professionals will improve care. The initiative, backed by the World Health Organization, will target both developed and developing countries. Headache disorders are a huge cost to society in lost productivity and sickness absence, say campaign organisers. However, many people are being denied access to effective, low-cost treatments. This is partly because headache disorders are not recognised as health conditions in some countries. However, it is widely recognised that on a global scale, headache disorders have low priority when it comes to allocating health-care resources. (C)BBC

Keyword: Pain & Touch
Link ID: 5193 - Posted: 03.27.2004

Using neurochemistry to try to unravel the experience of romantic passion By Barbara Smuts A male baboon named Sherlock sat on a cliff, unable to take his eyes off his favorite female, Cybelle, as she foraged far below. Each time Cybelle approached another adult male, Sherlock froze with tension, only to relax again when she ignored a potential rival. Finally, Cybelle glanced up and met his gaze. Instantly Sherlock flattened his ears and narrowed his eyes in what baboon researchers call the come-hither face. It worked; seconds later Cybelle sat by her guy, grooming him with gusto. After observing many similar scenarios, I realized that baboons, like humans, develop intense attractions to particular members of the opposite sex. Baboon heterosexual partnerships bear an intriguing resemblance to ours, but they also differ in important ways. For instance, baboons can simultaneously be "in love" with more than one individual, a capacity that, according to anthropologist Helen Fisher, most humans lack. Fisher is well known for her three previous books (The Sex Contract, Anatomy of Love and The First Sex), which bring an evolutionary perspective to myriad aspects of sex, love, and sex differences. This book is the best, in my view, because it goes beyond observable behaviors to consider their underlying brain mechanisms. Most people think of romantic love as a feeling. Fisher, however, views it as a drive so powerful that it can override other drives, such as hunger and thirst, render the most dignified person a fool, or bring rapture to an unassuming wallflower. © 1996-2004 Scientific American, Inc

Keyword: Sexual Behavior
Link ID: 5192 - Posted: 06.24.2010