By RICHARD A. FRIEDMAN, M.D. As a psychopharmacologist, I know that every patient responds slightly differently to medication. But it wasn't until I met Susan that I understood just how differently. She'd come to see me because she was depressed, and I'd successfully treated her with a course of Zoloft, a popular antidepressant. But as often happens, Susan's desire for sex had vanished along with her depressed mood. "I kind of miss it, but I feel really bad for my husband, who's getting very frustrated," she said. The sexual side effects of antidepressants like Zoloft and Prozac - the class of drugs known as selective serotonin reuptake inhibitors, or S.S.R.I.'s - are well known. The drugs frequently cause diminished libido, erectile dysfunction in men, and delayed orgasm or an inability to climax at all in women. The same flooding of the brain with serotonin that alleviates depression leads to sexual effects in many patients. Early on, the rates of sexual side effects from S.S.R.I.'s reported in the medical literature were quite low, in the range of 10 percent to 20 percent. But clinicians knew better. Most of their patients reported some sexual effects, and it quickly became clear that the early reports were wrong. Copyright 2005 The New York Times Company

Keyword: Depression; Sexual Behavior
Link ID: 6747 - Posted: 01.25.2005

Yawn. Stretch. Grumble. Retch. No matter. All muscle motion starts with a nerve signal: Move, muscle, now! You know the drill: Brain activates nerve, nerve stimulates muscle cell, and something happens. Things are different in the fruitfly. This mainstay of the compost heap and the biology lab beats its wings 200 times a second. Even Why Filers can do the math: 200 contractions of the muscles that lift the wings, and another 200 in the muscles that pull them back down. All in one second. That's a problem because it's much faster than nerves can trigger muscles, says Thomas Irving, associate professor of biology at the Illinois Institute of Technology, and director of the Biophysics Collaborative Access Team . "Human muscle needs a nerve impulse, but the insect has got to do it 200 times a second," and so the triggering "has to be done at the molecular level." To explore the molecular level, Irving and colleagues, including fruit-fly flight expert Michael Dickinson of Caltech, triggered some muscular activity of their own. They glued the head of a living fruitfly to a wire and placed it in a bath of X-rays at the Advanced Photon Source at Argonne National Laboratory in Illinois. They put on a light show to force the fly to adopt a steady wingbeat, and aimed brief surges of tightly focused X-rays at the critter's wing muscles. You can read their results in this week's Nature. ©2005, University of Wisconsin, Board of Regents.

Keyword: Muscles
Link ID: 6746 - Posted: 06.24.2010

Stevie Wonder and Ray Charles are often cited as anecdotal evidence that blindness confers superior musical ability. In fact, systematic studies have shown that blind persons perform nonvisual tasks better than those with sight. Neuroimaging studies have suggested that areas of the brain normally devoted to vision become active when blind persons perform nonvisual tasks, but much remains to be learned about the nature and extent of this phenomenon. A new study published in the open-access journal PLoS Biology finds a strong correlation between superior sound localization skills and increased activity in the brain's visual center. The task of localizing sound--which requires integrating information available to one ear only (monaural sounds available, for example, when one ear is plugged) or information derived from comparing sounds binaurally--is particularly suited to investigating the neural remapping that seems to follow vision loss. In a previous study, Franco Lepore and colleagues showed that people who lost their sight at an early age could localize sound, particularly from monaural cues, better than those who could see. These findings suggested that areas of the brain normally dedicated to processing visual stimuli (the visual cortex, located at the back of the brain in the occipital lobe) might play a role in processing sound in these individuals. In the new study, the authors hypothesized that if visual cortex recruitment bolstered auditory function in some individuals, then visual cortex activity would correlate with individual differences in performance, and the degree of activity should predict such differences.

Keyword: Hearing; Vision
Link ID: 6745 - Posted: 01.25.2005

Why females fall for captivating males that apparently give them nothing but their genes and little else is a puzzling question for evolutionary biologists. Females typically incur more survival costs than males in rearing offspring, especially when they choose flashy mates. So why do they do it? Megan Head and colleagues now report in the freely-available online journal PLoS Biology, the results of simultaneously measuring both the costs and benefits of mating to female crickets and their offspring and provide new evidence that the costs that females pay for mating with attractive males are balanced by, and may even be outweighed by, the indirect benefits of spawning offspring with elevated fitness. The authors paired females with either "attractive" or "unattractive" males (determining which males were attractive by running the equivalent of speed dating "tournaments") and measured the overall fitness consequences of the various unions. Although female crickets, they found, paid a higher survival price for mating with attractive males, these females produced both daughters that laid more eggs within a given time and sons that were more attractive. The benefit stems in large part, the authors argue, from siring "sexy" sons. Thus, by evaluating both the direct effects of mating on female lifetime fecundity and the indirect effects of offspring fitness, the authors determined the net consequences of a mating strategy.

Keyword: Sexual Behavior; Evolution
Link ID: 6744 - Posted: 01.25.2005

DALLAS – – Jumping on that treadmill or bike is not only good for one's health, but also can help significantly reduce depression, researchers at UT Southwestern Medical Center have found. The first study to look at exercise alone in treating mild to moderate depression in adults aged 20 to 45 showed that depressive symptoms were reduced almost 50 percent in individuals who participated in 30-minute aerobic exercise sessions three to five times a week. The results, published in the January issue of the American Journal of Preventive Medicine, are comparable to results from studies in which patients with mild to moderate depression were treated with antidepressants or cognitive therapy, said Dr. Madhukar Trivedi, professor of psychiatry and director of UT Southwestern's mood disorders research program. "The effect you find using aerobic exercise alone in treating clinical depression is similar to what you find with antidepressant medications," said Dr. Trivedi, a study author and holder of the Lydia Bryant Test Professorship in Psychiatric Research. "The key is the intensity of the exercise and continuing it for 30 to 35 minutes per day. It's not for the faint of heart."

Keyword: Depression
Link ID: 6743 - Posted: 06.24.2010

By Kristen Philipkoski You can try, but you can't ignore that angry voice yelling at you, or anyone else. Whether it's your dad, your girlfriend, your sister or a stranger, you must pay attention. Human brains are just wired that way, according to a study published in the Jan. 23 issue of Nature Neuroscience. Wrathful voices trigger a strong response in the brain, even when we are trying not to pay attention or the comments are meaningless, say researchers at the University of Geneva. The brain appears to place a high priority on processing urgent sounds, like angry voices, that might indicate a threat is present. So, try as we might, when someone is angry the brain cannot avoid noticing, regardless of what the fuss is all about. "The new finding (is) that the influence of attention cannot diminish the brain activity associated with certain types of salient input: in this case, angry voices," said G. Ron Mangun, a cognitive neuroscience professor at the University of California at Davis, who did not participate in the research. © Copyright 2005, Lycos, Inc.

Keyword: Emotions; Attention
Link ID: 6742 - Posted: 06.24.2010

A high resolution x-ray scanning technique can look inside a single brain tissue cell. Scientists say it will help to pin down the role of iron and other metals in neurological disorders such as Alzheimer's and Parkinson's disease. The new technique, developed by Keele University, can identify where the compounds are within the brain, and thus whether they are harmful. Details are published in the journal Interface. The researchers hope the scan will aid the development of new treatments and techniques for early diagnosis. High concentrations of iron compounds in brain tissue have been linked to degenerative neurological diseases for more than 50 years. Iron is an essential element for living organisms - but in some circumstances it can be toxic. However, its precise role in the development of conditions such as Alzheimer's and Parkinson's disease is not known. This is because the staining techniques used for identifying iron compounds to date cannot identify precisely where the iron is or what type of iron compound it is. Researcher Professor Jon Dobson said: "This work will enable scientists to understand the properties of iron compounds and where they are in relation to structures in the tissue. "Using this information, we are designing techniques that can identify them in the early stages for people at risk which will aid the development of suitable treatment. "It also means that we may be able to develop treatments for those whose symptoms are already well-established." (C)BBC

Keyword: Brain imaging
Link ID: 6741 - Posted: 01.24.2005

By NATALIE ANGIER and KENNETH CHANG hen Lawrence H. Summers, the president of Harvard, suggested this month that one factor in women's lagging progress in science and mathematics might be innate differences between the sexes, he slapped a bit of brimstone into a debate that has simmered for decades. And though his comments elicited so many fierce reactions that he quickly apologized, many were left to wonder: Did he have a point? Has science found compelling evidence of inherent sex disparities in the relevant skills, or perhaps in the drive to succeed at all costs, that could help account for the persistent paucity of women in science generally, and at the upper tiers of the profession in particular? Researchers who have explored the subject of sex differences from every conceivable angle and organ say that yes, there are a host of discrepancies between men and women - in their average scores on tests of quantitative skills, in their attitudes toward math and science, in the architecture of their brains, in the way they metabolize medications, including those that affect the brain. Yet despite the desire for tidy and definitive answers to complex questions, researchers warn that the mere finding of a difference in form does not mean a difference in function or output inevitably follows. Copyright 2005 The New York Times Company

Keyword: Sexual Behavior
Link ID: 6740 - Posted: 01.24.2005

Washington -- Carrying the higher-risk genotype for Alzheimer's disease appears to render even healthy older people subject to major problems with prospective memory, the ability to remember what to do in the future. For the group studied, this could affect important behaviors such as remembering to take medicine at a certain time or getting to a doctor's appointment. The research appears in the January issue of Neuropsychology, which is published by the American Psychological Association. People with this genotype have a certain variety, or allele, of a gene called ApoE (for Apolipoprotein E), which switches on production of a protein that helps carry cholesterol in the blood. ApoE has three alleles and about one out of five people carry the e-4 allele. It makes homozygous carriers, who carry this variation on both of their ApoE genes, eight times as likely to develop Alzheimer's disease as non-carriers. Heterozygous carriers, who carry the high-risk variation only on half the pair, have a three-fold higher risk. Neuro- psychologists have looked at the episodic, or retrospective, memory, of e-4 carriers, especially for recent events. This study was the first to look at their prospective memory. At the University of New Mexico, a group of 32 healthy, dementia-free adults between ages of 60 and 87 were drawn from a larger study of aging and divided evenly between people with and people without the e-4 allele.

Keyword: Alzheimers; Learning & Memory
Link ID: 6739 - Posted: 01.24.2005

There is no association between two specific personality traits – neuroticism and extroversion – and cancer, according to a new study, one of the largest prospective twin studies to examine this issue. The study, published in the March 1, 2005 issue of CANCER (http://www.interscience.wiley.com/cancer-newsroom), a peer-reviewed journal of the American Cancer Society, also finds no evidence that personality traits indirectly lead to cancer through behavioral factors, such as smoking. Personality traits are popularly cited as risk factors for cancer. Some studies have gone so far as to suggest that two traits in particular, neuroticism and extroversion, may be such risk factors. Scientists have hypothesized that a high degree of extroversion and low degree of neuroticism are associated with an increased risk. Some studies further show that these personality traits influence known risk behaviors that would explain the increased cancer risk. However, other studies, some with larger study populations and better study designs, have found no such associations. Pernille Hansen, M.A. of the Department of Psychosocial Cancer Research at the Institute of Cancer Epidemiology in Copenhagen, Denmark led a team of investigators who reviewed cancer history, health behavior, and personality trait data collected from 29,595 Swedish twins enrolled in the Swedish Twin Registry. These patients were born between 1926-1958 and were followed an average 25 years

Keyword: Neuroimmunology
Link ID: 6738 - Posted: 06.24.2010

By Joshua DavisPage 1 of 4 next » Bryan Peterson sat on the toilet in the master bathroom of his Palm Springs, California, home and tried to find a vein between his knuckles. It was virgin territory - he had never injected himself in a spot he couldn't cover up. But now that he'd been fired from his job in the estimating department of a construction company, he didn't care about covering up anymore. Plus, he couldn't find a vein in his arms, which were swollen with pools of pus and heroin. The thin, translucent blue veins snaking across the back of his hand filled him with joy. He slid the needle in beside his knucklebone. It hurt. Two weeks later, he'd blown out all the tiny veins in his hands and feet. Unable to absorb all that fluid, they burst, adding more blood to the already toxic mix festering under his skin. He started plunging the needle deep into his bicep, shooting heroin directly into the muscle. The drug seemed to sizzle as he injected it. Peterson was 36 and had been addicted for three years. Before that, he was just a normal working guy who liked to play guitar in a local rock band. Over the past two and a half years, he'd tried to kick his habit cold turkey three times and attended a few Narcotics Anonymous meetings. He'd make it through the first step - acknowledging that he was powerless over his addiction - and that was it. Even with the group therapy sessions and encouragement from fellow addicts, he couldn't stay clean for more than 10 days. The withdrawal pains were so unbearable, he fantasized about cutting off his legs to stop the aching. And when the pain subsided for a moment, he was racked with nausea and diarrhea. His body was holding him hostage: Either take the drug, it said, or you'll feel so much pain you'll want to die. Then one day Peterson was talking to a friend who mentioned a miracle treatment gaining popularity in the Los Angeles area. © Copyright© 1993-2005/ © Copyright 2005, Lycos, Inc.

Keyword: Drug Abuse
Link ID: 6737 - Posted: 06.24.2010

Scientists have reversed the damage caused to the brain by Alzheimer's disease during tests on mice. The US team used an antibody to remove the build up of potentially damaging deposits from the area of the brain responsible for memory and cognition. The treatment reversed the nerve cell damage in days, Washington University School of Medicine researchers said. UK experts described the findings, published in the Journal of Clinical Investigation, as "exciting". Prior to the study, it was thought that once the damage had been caused to the brain there was no way of repairing it. Lead author Robert Brendza said: "We thought that clearing the plaques (deposits) would halt the progression of the damage. "But what we saw was much more striking - in just three days there were 20 to 25% reductions in the number or six of the existing swellings." He said more research was needed to see if the effects could be repeated in humans with the degenerative brain disorder for which there is no cure. It is estimated that 2% to 5% of people over 65 years of age and up to 20% of those over 85 years of age have Alzheimer's. The cause of the disease is not known although people with Alzheimer's do have a build up of abeta, a glycoprotein, which could be responsible for the nerve cell damage. Mice with a build up of abeta were injected with the antibody and then using a dye to give detailed images of the nerve cell branches, the team were able to monitor the improvement over a few days. (C)BBC

Keyword: Alzheimers
Link ID: 6736 - Posted: 01.22.2005

By ANDREW POLLACK Regulators are reviewing the safety of the Alzheimer's disease drug Reminyl after data from two clinical trials indicated that people taking the drug had a much higher death rate than those taking a placebo. The review was announced yesterday by Johnson & Johnson, which said it was in discussions with the Food and Drug Administration and regulators in Europe and Canada. The trials, which involved about 2,000 patients in 16 countries, were looking at whether Reminyl could be used to treat mild cognitive impairment, a form of memory loss that is often a precursor to Alzheimer's disease. Reminyl is approved in 69 countries as a treatment for mild to moderate Alzheimer's but not for mild cognitive impairment. In the trials, which lasted two years, 15 patients taking Reminyl died compared with 5 taking the placebo. There were various causes of death but many were from heart attacks and strokes, a company spokeswoman, Carol Goodrich, said. The announcement comes at a time of heightened concern over the safety of widely used drugs after the withdrawal from the market of Merck's pain reliever, Vioxx, which studies indicated posed an increased risk of heart attacks and strokes. Copyright 2005 The New York Times Company

Keyword: Alzheimers
Link ID: 6735 - Posted: 01.22.2005

According to conventional wisdom, old dogs and new tricks aren’t a good match. But a new study of beagles finds that regular physical activity, mental stimulation, and a diet rich in antioxidants can help keep aging canine — and perhaps human — brains in tip-top shape. The research, supported by the National Institute on Aging (NIA), a part of the National Institutes of Health (NIH), is among the first to examine the combined effects of these interventions and suggests that diet and mental exercise may work more effectively in combination than by themselves. During the two-year longitudinal study, William Milgram, Ph.D., of the University of Toronto, Elizabeth Head, Ph.D., and Carl Cotman, Ph.D., of the University of California, Irvine and their colleagues found older beagles performed better on cognitive tests and were more likely to learn new tasks when they were fed a diet fortified with plenty of fruits, vegetables and vitamins, were exercised at least twice weekly, and were given the opportunity to play with other dogs and a variety of stimulating toys. The study* is reported in the January 2005 Neurobiology of Aging. Dogs are an important model of cognitive aging, and these findings could have important implications for people. Like humans, dogs engage in complex cognitive strategies and have a more complicated brain structure than many other animals. Dogs also process dietary nutrients in ways similar to humans. And like people, dogs are susceptible to age-related declines in learning and memory, and can develop neuropathology similar to Alzheimer’s disease.

Keyword: Alzheimers
Link ID: 6734 - Posted: 06.24.2010

Peter Weiss In a Los Angeles laboratory, researchers have let loose scores of what amount to living micromachines. Dwarfed by a comma, each tiny device consists of an arch of gold coated along its inner surface with a sheath of cardiac muscle grown from rat cells. With each of the muscle bundles' automatic cycles of contraction and relaxation, the device takes a step. Viewed under a microscope, "they move very fast," says bioengineer Jianzhong Xi of the University of California, Los Angeles (UCLA). "The first time I saw that, it was kind of scary." Xi and his UCLA colleagues Jacob J. Schmidt and Carlo D. Montemagno describe their musclebots in the February Nature Materials. Microcontraptions of this sort may someday make pinpoint deliveries of drugs to cells or shuttle minuscule components during the manufacture of other itsy machines or structures, Xi says. Variations on the same design could lead to muscle-driven power supplies for microdevices or laboratory test beds for studying properties of muscle tissue. Because the musclebot is both minuscule and designed to operate in body fluids, "this is the Fantastic Voyage kind of thing" that might someday roam the bloodstream and carry out on-the-spot surgery or disease treatments, comments physicist James Castracane of the State University of New York in Albany. Copyright ©2005 Science Service.

Keyword: Muscles
Link ID: 6733 - Posted: 06.24.2010

Reviewed by Elizabeth Svoboda Alex, an African Grey parrot, knows what he wants and intends to get it. "Want nut!" he squawks at his scientist owner, Irene Pepperberg. Before he can get his reward, though, he has to perform a task. "What matter?" Pepperberg asks Alex, showing him a cloth ball. "Wool," he answers correctly -- he can also identify wood, plastic, metal and paper -- then munches on his requested treat. Unlike some parrots with a vast capacity for mimicry, Alex has a "vocabulary" of only about 100 words, but he has an important cognitive advantage: He actually seems to know what he's talking about. Watching Alex and Pepperberg interact, it's easy to conclude that the parrot, like Hugh Lofting's Gub-Gub the pig or Jip the dog, has mastered the fundamentals of human language. Not so fast, says Stephen R. Anderson, a professor of linguistics and cognitive science at Yale University. Alex and animals like him -- such as Koko, the famous gorilla who has learned more than 1,000 hand signs from her keepers -- are remarkable, he concedes. Nevertheless, their feats don't prove that the fictional Dr. Dolittle was right in his belief that animals can talk. Why can't we say that Alex and Koko, who draw upon learned sets of symbols to communicate, are using language? Simple, Anderson answers in "Dr. Dolittle's Delusion": They lack syntax. In our amazement that birds and gorillas can correctly refer to individual objects, we lose sight of how intricate linguistic structure is and how unequipped animals are to grasp it. Through years of training, Alex has learned to apply English words to things in his environment ("wool" for the cloth ball, "nut" for his beloved cashews), but no reward can coax him to string these expressions into a meaningful new combination of words, as humans can. Likewise, although Koko scores 60 percent correct in tests in which she gives a sign for each object presented to her, her attempts to combine signs result in magnetic-poetry-like hodgepodge such as "You Koko love knee do." ©2005 San Francisco Chronicle

Keyword: Language
Link ID: 6732 - Posted: 06.24.2010

St. Louis, -- Brain cells in a mouse model of Alzheimer's disease have surprised scientists with their ability to recuperate after the disorder's characteristic brain plaques are removed. Researchers at Washington University School of Medicine in St. Louis injected mice with an antibody for a key component of brain plaques, the amyloid beta (Abeta) peptide. In areas of the brain where antibodies cleared plaques, many of the swellings previously observed on nerve cell branches rapidly disappeared. "These swellings represent structural damage that seemed to be well established and stable, but clearing out the plaques often led to rapid recovery of normal structure over a few days," says senior author David H. Holtzman, M.D., the Charlotte and Paul Hagemann Professor and head of the Department of Neurology. "This provides confirmation of the potential benefits of plaque-clearing treatments and also gets us rethinking our theories on how plaques cause nerve cell damage." Prior to the experiment, Holtzman and some other scientists had regarded plaque damage to nerve cells as a fait accompli--something that the plaques only needed to inflict on nerve cells once. According to Holtzman, the new results suggest that plaques might not just cause damage but also somehow actively maintain it. The study, will appear in the Feb. 5 issue of the Journal of Clinical Investigation.

Keyword: Alzheimers
Link ID: 6731 - Posted: 01.21.2005

According to the Centers for Disease Control, tobacco use remains the leading preventable cause of death in the United States, causing more than 440,000 deaths each year and resulting in an annual cost of more than $75 billion in direct medical costs. The substance that makes cigarettes addictive is nicotine, which enhances the release of a neurotransmitter called dopamine, which is associated with the pleasure people get from eating, sex, and drugs. But Henry Lester, a neuroscientist at the California Institute of Technology, says nailing down exactly how nicotine behaves in the brain has been difficult. "We have known for, oh goodness, 450 years that nicotine does act on the body," he says. "But it's been unclear until the present which particular molecules it does act on. The question is, which of the various—and there are more than a dozen nicotine receptors in the body—is the one responsible for nicotine addiction?" Lester and his team believe they may have come closer to the answer. The brain has more than a dozen molecules—each with several "subunit" proteins—that respond to nicotine. These "nicotinic receptors" might act together or independently to cause addiction. Lester and his colleagues picked just one of them—the subunit alpha4 receptor—and genetically enhanced it in mice, creating "hypersensitive knock-in" mice. © ScienCentral, 2000- 2005.

Keyword: Drug Abuse
Link ID: 6730 - Posted: 06.24.2010

While there are essentially no disparities in general intelligence between the sexes, a UC Irvine study has found significant differences in brain areas where males and females manifest their intelligence. The study shows women having more white matter and men more gray matter related to intellectual skill, revealing that no single neuroanatomical structure determines general intelligence and that different types of brain designs are capable of producing equivalent intellectual performance. “These findings suggest that human evolution has created two different types of brains designed for equally intelligent behavior,” said Richard Haier, professor of psychology in the Department of Pediatrics and longtime human intelligence researcher, who led the study with colleagues at UCI and the University of New Mexico. “In addition, by pinpointing these gender-based intelligence areas, the study has the potential to aid research on dementia and other cognitive-impairment diseases in the brain.” Study results appear on the online version of NeuroImage. © Copyright 2002-2005 UC Regents

Keyword: Intelligence
Link ID: 6729 - Posted: 06.24.2010

Roxanne Khamsi One assumption lies at the root of efforts to keep the meat we eat safe from mad cow disease: that tissues beyond an animal's brain, spinal cord and immune system are free of the prions that cause the disease. A disturbing study now shows that assumption to be false. Researchers have found that if an animal falls ill with another infection, its immune response can carry large numbers of prions to organs throughout its body. "The rules no longer apply," warns pathologist Adriano Aguzzi at Zurich University Hospital, Switzerland, who led the research. Mad cow disease, more correctly known as bovine spongiform encephalopathy (BSE), is believed to be caused by rogue proteins called prions. When these prions enter the human food chain, they can cause the equivalent disease in humans, called new-variant Creutzfeldt-Jakob disease (vCJD). ©2005 Nature Publishing Group

Keyword: Prions
Link ID: 6728 - Posted: 06.24.2010