Thomas H. Maugh, Los Angeles Times Lovastatin, a widely used cholesterol-lowering drug, reverses common learning disabilities in mice, offering the first hope for a treatment of the problem in humans, UCLA researchers reported Monday. Three separate human trials in both children and adults will begin at UCLA and other U.S. and European locations within weeks, said Dr. Alcino Silva, a neurobiologist at UCLA and the lead author of a paper appearing in the journal Current Biology. "Currently, there are no treatment options for these people," Silva said. "That's why our findings are so exciting from a clinical perspective." Lovastatin, trade-named Mevacor, is one of a family of drugs known collectively as statins that have revolutionized the treatment of high cholesterol. The drugs, first introduced in the 1990s and taken daily by millions of people at risk for heart disease and other problems, have been widely recognized as safe. The learning problems studied by the researchers were caused by a genetic defect called neurofibromatosis 1, the most common genetic cause of learning disabilities. It affects 1 in every 3,000 to 4,000 people. The learning disabilities include poor attention spans, difficulties in carrying out tasks involving spatial abilities and problems learning new tasks. ©2005 San Francisco Chronicle

Keyword: Learning & Memory; Genes & Behavior
Link ID: 8143 - Posted: 06.24.2010

Every sight, sound, smell, and touch sends a barrage of electrical signals zipping to the brain. But how the subjective experience of, say, a redolent pink rose emerges from this flurry of neural activity is mysterious. Now researchers say they've found an important piece of the puzzle, identifying monkey neurons that appear to convey the perception of a simple touch. The first relay station for incoming touch signals in the cerebral cortex is called the primary somatosensory cortex, or S1 for short. Neurons here rev up whenever something brushes or pokes the body, and many researchers have thought that this neural activity is responsible for the subjective experience of touch, says Ranulfo Romo, a neuroscientist at the Universidad Nacional Autónoma de México in Mexico City. But when Romo and colleague Victor de Lafuente took a closer look at neural activity in S1, they began to doubt this assumption. The pair trained monkeys to press one of two buttons to indicate whether or not they'd felt a vibration applied to one finger. Correct responses earned a reward. Neurons in S1 scale their activity according to the strength of the vibration, the researchers found, but don't necessarily reflect what the monkeys perceive. For example, when the researchers made the task difficult by delivering a barely detectable vibration, monkeys reported catching the vibe only some of the time. But S1 neurons responded similarly to such weak vibrations regardless of which button the monkeys pushed. © 2005 by the American Association for the Advancement of Science.

Keyword: Pain & Touch
Link ID: 8142 - Posted: 06.24.2010

A report in the November Cell Metabolism reveals powerful effects of light on the adrenal glands, a finding that might explain the broad benefits of bright light therapy for a variety of conditions, including sleep and depressive disorders, according to researchers. The body's two adrenal glands sit atop each kidney, where they secrete hormones that regulate stress response and metabolism. The researchers found in mice that light sparks a cascade of gene activity in the adrenal gland through its effects on the suprachiasmatic nucleus (SCN). Located in the brain region called the hypothalamus, the SCN is the seat of the circadian clock, the body's internal clock that regulates the roughly 24-hour cycle of biological processes. Moreover, the researchers report, the gene expression changes accompany a massive surge of the steroid hormone corticosterone in the animals' blood and brain. That hormonal response increased with light intensity, they found. Glucocorticoids--including cortisone in humans and corticosterone in mice--play many roles throughout the body, including metabolic response to starvation, antiinflammatory immune response, and the timing of circadian rhythms in peripheral organs. Therefore, light-induced secretion of glucocorticoids may play a key role in physiological changes in the body and the brain evoked by light, reported study author Hitoshi Okamura of Kobe University Graduate School of Medicine in Japan

Keyword: Biological Rhythms
Link ID: 8141 - Posted: 11.09.2005

Roxanne Khamsi There's a new lesson to be learned about statins, a class of widely prescribed drugs that lower cholesterol. A study in mice suggests that this type of medication could reverse a learning disorder known as neurofibromatosis. The disorder, also called NF1, affects about 1 in every 4,000 children and can cause learning disabilities, coordination problems and benign tumours that grow on nerve tissue. Researchers have found that mutations in a single gene are to blame for NF1. The affected gene fails to produce a protein called neurofibromin, which normally keeps another protein, Ras, in check. Evidence from mouse studies suggests that an overabundance of active Ras results in abnormal nerve-cell responses in the brain. Ras also requires cholesterol compounds to function, and this led medical student Steven Kushner to wonder whether cholesterol-busting drugs could keep Ras in check, should neurofibromin not be up to the task. Kushner stumbled on the idea after learning about statins while on a clinical rotation. "He came to my lab at one in the morning and said 'I think I have a solution'," says his supervisor, Alcino Silva of the University of California, Los Angeles. ©2005 Nature Publishing Group

Keyword: Learning & Memory
Link ID: 8140 - Posted: 06.24.2010

Smokers are twice as likely to suffer post-traumatic stress disorder than non-smokers , according to a study of twin soldiers. It is estimated that after experiencing severe trauma, about one-third of people go on to suffer PTSD, a mental illness characterised by anxiety, flashbacks and panic attacks. Nicotine dependence has been associated with PTSD before, but the exact nature of the link has never been clear. The new study establishes smoking as a key risk factor in pre-disposing people to PTSD. Karestan Koenen, at the Harvard School of Public Health in Cambridge, US, and colleagues, looked at the health records of 6744 pairs of male twins who had served in the US military during the Vietnam era, about half of whom were identical twins. Shared genetic factors explained 63% of the overlap between PTSD and nicotine dependence in the twins. “Some of the same genes that influence risk for PTSD may influence risk for nicotine dependence, and vice versa,” Koenen said. But the researchers found that those with a pre-existing nicotine dependence who were then exposed to trauma had twice the risk of developing PTSD, compared to non-smokers who experienced trauma. © Copyright Reed Business Information Ltd.

Keyword: Drug Abuse; Stress
Link ID: 8139 - Posted: 06.24.2010

STANFORD, Calif. - Researchers at the Stanford University School of Medicine have shown for the first time that a sample of children who either have or are at high risk for bipolar disorder score higher on a creativity index than healthy children. The findings add to existing evidence that a link exists between mood disorders and creativity. The small study, published in the November issue of the Journal of Psychiatric Research, compared creativity test scores of children of healthy parents with the scores of children of bipolar parents. Children with the bipolar parents - even those who were not bipolar themselves - scored higher than the healthy children. "I think it's fascinating," said Kiki Chang, MD, assistant professor of psychiatry and behavioral sciences and co-author of the paper. "There is a reason that many people who have bipolar disorder become very successful, and these findings address the positive aspects of having this illness." Many scientists believe that a relationship exists between creativity and bipolar disorder, which was formerly called manic-depressive illness and is marked by dramatic shifts in a person's mood, energy and ability to function. Numerous studies have examined this link; several have shown that artists and writers may have two to three times more incidences of psychosis, mood disorders or suicide when compared with people in less creative professions.

Keyword: Schizophrenia
Link ID: 8138 - Posted: 11.09.2005

Women get more of a buzz out of cartoons, a brain-imaging study has found, with their brains feeling more rewarded by a funny joke than those of men. Women and men are often perceived as having differences in their senses of humour but, until now, there had been no neurological evidence for such suspicions. The new brain scanning study showed that although men and women tended to agree on which of the single-panel cartoons they were shown were funny, they processed the humour differently in their brains. In particular, women appear to have a lower expectation that the cartoon will be funny than men. “Women appear to have less expectation of a reward, which in this case was the punch line of the cartoon. So when they got to the joke’s punch line, they were more pleased about it,” says Allan Reiss, one of the study’s authors, at Stanford University School of Medicine in California, US. The group of 10 women and 10 men were shown a series of black and white cartoons. They rated the cartoons for funniness while functional magnetic resonance imaging (fMRI) identified the active areas of their brains. The level of activity in those areas was measured using a technique that analyses the level of oxygenation in the blood. © Copyright Reed Business Information Ltd

Keyword: Sexual Behavior; Emotions
Link ID: 8137 - Posted: 06.24.2010

By Simon Busch Special to The Washington Post I don't know what was wrong with me: a case of ill fit with the world, I guess. I suddenly kept being confronted by the fact of my own mortality, like a glacier in my path, and seizing up with panic. I told my doctor and, as luck would have it, he was branching into hypnotherapy and wanted to try it out on me. He was quite the evangelist for the treatment. Hypnosis was no mere stage trick, he insisted: A patient of his had recently had major dental surgery -- I imagined pile drivers and a building site -- solely anesthetized by the doctor's suggestion. As for quitting smoking, why, the cigarettes virtually extinguished themselves. My panic attacks should likewise succumb to the powers of his mind. On my next appointment, he led me to a room where he gestured for me to lie down on a very purple, soft leather couch while he took the armchair opposite. He put a CD of New Age mood music on the stereo -- some sort of ode to aquatic life-forms, I noticed by the cover -- and told me to focus on a psychedelic spiral pattern inscribed on a small piece of paper attached to the ceiling, while simultaneously concentrating on the sound of his voice. © 2005 The Washington Post Company

Keyword: Depression
Link ID: 8136 - Posted: 06.24.2010

By KATE MURPHY As an author of several books about thyroid disease who also moderates a Web site on the topic, Mary J. Shomon gets more than 1,000 e-mail messages a week. "I hear from people all the time who are fighting to be treated," said Ms. Shomon, a patient advocate. Most of the postings on her online message board at thyroid.about.com (presented by a division of The New York Times Company) are from women who report weight gain, fatigue, memory problems and depression. Many say they have thinning hair, dry skin and cold hands and feet. These are classic signs of an underactive thyroid, or hypothyroidism. But the patients say their doctors will not prescribe medicine because their blood tests are normal. But just what is "normal" is "an incredibly controversial question," said Dr. David Cooper, director of the endocrinology division at Sinai Hospital in Baltimore and a professor at Johns Hopkins School of Medicine. For two years, endocrinologists have been arguing about where to set the bar for the diagnosis and treatment of a failing thyroid, the gland in the neck responsible for secreting metabolism-regulating hormones. Some say a single, mildly elevated blood test is enough to start drug therapy; others advocate for more compelling evidence. Copyright 2005 The New York Times Company

Keyword: Hormones & Behavior
Link ID: 8135 - Posted: 11.08.2005

By JANE E. BRODY Paula Schneider was 38 when she developed what doctors first thought was carpal tunnel syndrome. But soon the trouble she had moving her right arm spread to her neck and back and then the whole body. She lost control of her limbs, head and torso, leaving her unable to walk, sit, eat or do much of anything. It was as if her entire body had been inhabited by jitterbugs that determined her every move. More Personal Health Columns "I couldn't eat like a normal person, brush my teeth or drink from a glass because it would break when I tried to put it down," Ms. Schneider recalled recently at a demonstration on movement disorders at Beth Israel Hospital in New York. The cause, she eventually learned, was a severe movement disorder called generalized dystonia. Various medications helped for a while. So did multiple localized injections of Botox to disrupt the flow of nerve impulses to muscles that were spastic or excessively contracted. But the benefits were limited and short-lived. She said she spent 12 years in excruciating pain. Copyright 2005 The New York Times Company

Keyword: Movement Disorders
Link ID: 8134 - Posted: 11.08.2005

By CARL ZIMMER In a laboratory at Indiana State University, a dozen green iguanas sprawl tranquilly in terrariums. They while away the hours basking under their heat lamps, and at night they close both eyes - or sometimes just one. They lead comfortable lives pretty much indistinguishable from any ordinary pet iguana, except for one notable exception: the bundles of brain-wave recording wires that trail from their heads. A team of scientists at Indiana State would like to know what happens in the brains of the iguanas when the lights go out. Do they sleep as we do? Do they shut the whole brain down, for example, or can they keep one half awake? These scientists in Terre Haute hope the iguanas will also help shed some light on an even more fundamental question: why sleep even exists. "Sleep has attracted a tremendous amount of attention in science, but we really don't know what sleep is," said Steven Lima, a biologist at Indiana State. Dr. Lima belongs to a small but growing group of scientists who are pushing sleep research deep into the animal kingdom. They suspect that most animal species need to sleep, suggesting that human slumber has an evolutionary history reaching back over half a billion years. Copyright 2005 The New York Times Company

Keyword: Sleep
Link ID: 8133 - Posted: 11.08.2005

STANFORD, Calif. - Need more evidence that men and women are different? Look no further than the Sunday funnies. According to a new Stanford University School of Medicine study, gender affects the way a person's brain responds to humor. The first-of-its-kind imaging study showed that women activate the parts of the brain involved in language processing and working memory more than men when viewing funny cartoons. Women were also more likely to activate with greater intensity the part of the brain that generates rewarding feelings in response to new experiences. "The results help explain previous findings suggesting women and men differ in how humor is used and appreciated," said Allan Reiss, MD, the Howard C. Robbins Professor of Psychiatry and Behavioral Sciences and director of the Center for Interdisciplinary Brain Sciences Research. He added that the results, which appear in the Nov. 7 online issue of the Proceedings of the National Academy of Sciences, could lead to a better understanding of medical conditions such as depression and cataplexy. Researchers know that a number of brain structures, including the prefrontal cortex, which is involved in language processing and memory, are involved in humor appreciation. In 2003, Reiss and colleagues showed for the first time that the brain's mesolimbic reward center, which is responsible for the rewarding feelings that follow such events as monetary gain or cocaine use, is also activated by humor.

Keyword: Sexual Behavior; Brain imaging
Link ID: 8132 - Posted: 11.08.2005

During our waking hours, our brains are inundated with sensory information that shifts from one moment to the next. Recognizing meaningful associations between different snippets of this information is a basic form of learning that is essential for survival, even for animals with much simpler brains than our own. For learning to occur, these associations must be made and reinforced in some way at the neuronal level, but how this happens is poorly understood. Research reported this week sheds light on this problem by identifying a group of neurons whose activity changes during the learning process in a way that reflects the new association that is formed between two different sensory stimuli. The findings are reported in Current Biology by André Fiala and colleagues at Bayerische Julius-Maximilians-Universität Würzburg, Germany. To address the question of how the relevance of a stimulus is represented at the level of neuronal cells, the researchers used the fruit fly Drosophila as a model organism. These tiny animals can be trained to associate an otherwise neutral odor stimulus with a negative experience, such as a small electric shock, and ultimately learn to avoid this odor. Using sensitive imaging methods, the researchers observed the activity of certain neurons within the fly's brain during such training. They found that prior to training, these cells, which release the neurotransmitter dopamine, become especially activated if the negative stimulus--the small shock--occurs, but show only a weak activity in response to odors.

Keyword: Learning & Memory
Link ID: 8131 - Posted: 11.08.2005

We humans are creatures of habit, whether they're good… "I've been trying to do a regular exercise habit, but it's been on and off," says Erwin Lara from New Jersey. … or not so good. "If I have a cigarette in my hand I need a coffee in my other hand and if I have a coffee in one hand I need a cigarette in my other hand," admits New Yorker Robert Noriega. We all know habits are hard to kick, but what's actually going on inside our brains? Massachusetts Institute of Technology neuroscientist Ann Graybiel thinks she knows, and she may be able to explain why many of us fall back into bad habits even after years of being good. "We all hear stories of smokers who try so hard to quit smoking cigarettes and they finally quit," she says. " They haven't smoked in years, and then one day, they're in that very situation where they used to smoke, and a flood of who knows what, memory or something, triggers off the pattern and all of a sudden the habit is back." © ScienCentral, 2000-2005.

Keyword: Drug Abuse
Link ID: 8130 - Posted: 06.24.2010

Certain behaviors, such as eating, drinking and urinating, are so crucial to survival that the brains of all vertebrates contain clusters of nerve cells that can suppress pain long enough to allow the animal to eat, drink -- or pee -- in peace. A report from researchers at the University of Chicago, published early online in the Proceedings of the National Academy of Sciences, shows that by activating "OFF" cells and shutting down "ON" cells in the ventromedial medulla (VMM) – a small region in the brain stem – animals provide themselves with a form of "eating-induced analgesia," allowing them to complete essential tasks even in a difficult situation. "Escaping pain and potential dangers may be important protective behaviors, but eating, drinking, and eliminating wastes are absolutely essential," said study author Peggy Mason, Ph.D., professor in the department of neurobiology, pharmacology and physiology (NPP) at the University of Chicago. "What we found was a very effective system that lets these animals focus on the essentials and postpone concerns that are slightly less pressing. It's as if they could give themselves a six-second dose of morphine, allowing hunger to override pain."

Keyword: Pain & Touch
Link ID: 8129 - Posted: 06.24.2010

(Philadelphia, PA) - Researchers may have discovered a new way that may ultimately assist in the early diagnosis of schizophrenia - by utilizing MRI to study the patient's brain. Researchers at the University of Pennsylvania Health System (UPHS) looked for subtle brain abnormalities that cannot be seen by the human eye. A study examined the entire brain, looking at distributed patterns of abnormalities rather than differences in specific regions of the brain. "In this study, we used high-dimensional shape transformations in which we compared a brain image with a template of a normal brain. Through this comparison, we then determined where and how the patient's brain differed from healthy controls," explained Christos Davatzikos, PhD, Director of the Section of Biomedical Image Analysis in the Department of Radiology at Penn. "These methods are able to identify abnormalities that could not be detected by human inspection of the images created via MRI And, up until now, structural MRI has typically been used to diagnose physical anomalies like stroke or tumors, but it has not been helpful for diagnosis of psychiatric diseases." Davatzikos says, "MRI produces images which are traditionally read mostly by radiologists. Now, we can do a quantitative reading of these images - bringing out information that is not obvious to the eye; one can think of computer readings as computational scanners. It's a second level that says 'analyze this image and produce another image that highlights subtle abnormalities in the brain.'

Keyword: Schizophrenia; Brain imaging
Link ID: 8128 - Posted: 11.08.2005

Roxanne Khamsi Can depression be explained by a simple chemical imbalance in the brain? A pair of researchers has complained that the evidence for this is weak, and that drug companies should not be allowed to push this message in their advertisements. After being bombarded by messages that depression is caused by the lack of a certain chemical in the brain, say the researchers, patients may be sceptical of other kinds of treatment, including other drugs and talking to a therapist. "That message [in the advertisements] is at odds with what's in the scientific literature," says Jonathan Leo of the Lake Erie College of Osteopathic Medicine in Bradenton, Florida, who co-authors an essay on the subject in PLoS Medicine this week1. The duo would like the Food and Drug Administration (FDA), which regulates drug advertising in the United States, to take a look at antidepressant ads and issue warnings to any firm that does not comply with its rules. At issue are a class of antidepressant drugs called selective serotonin reuptake inhibitors (SSRIs). The class includes such blockbusters as Prozac (fluoxetine), Zoloft (sertraline) and Paxil (paroxetine). ©2005 Nature Publishing Group

Keyword: Depression
Link ID: 8127 - Posted: 06.24.2010

A cure for one of the most common forms of learning disability may be on the horizon, US researchers have revealed. They reversed the condition in adult mice born with it, curing their learning disabilities by using a commonly prescribed drug. The researchers say the technique could potentially lead to treatments for other learning disabilities. Neurofibromatosis type I (NF1) is a condition caused by a single gene defect that affects more than 1 in 3000 people. The defect is either inherited or caused by a spontaneous mutation, which can then be inherited. NF1 causes developmental cognitive disabilities in up to half of those with the defective gene, including deficits in memory, motor coordination and spatial learning. It can also cause attention-deficit hyperactivity disorder (ADHD). Previous mouse studies show the cognitive deficits result from the mutant gene causing over-production of a molecule called p21Ras. This leads to an imbalance between the signals that activate brain cells and those that inhibit them, creating problems in the cell-to-cell communication needed for learning. Neurobiologist Alcino Silva and colleagues at the University of California, Los Angeles, US, tried a commonly prescribed cholesterol-lowering statin drug – called lovastatin – on adult mice with the NF1 mutation. In a series of experiments to test their cognitive functions, the team showed that the drug reversed the learning disabilities and brought the cognitive functions of the mice up to normal levels. © Copyright Reed Business Information Ltd.

Keyword: Learning & Memory
Link ID: 8126 - Posted: 06.24.2010

The female hormone oestrogen could give women the edge when it comes to tasks such as safe driving, say researchers. Tests showed attention span and ability to learn rules were far better among women than men. The Bradford University scientists told a hormone conference in London how tasks requiring mental flexibility favour women over men. A woman's oestrogen levels may prime the part of the brain involved in such skills - the frontal lobe - they said. They asked 43 men and women aged 18-35 to perform a battery of neuropsychological tests that assessed skills such as spatial recognition memory, rule learning, attention, planning and motor control. The women were far better at being able to shift their attention from one stimulus to another, making it easier for them to perform everyday actions like driving and reading. This might explain why girls find it easier than boys to concentrate at school and why women are more careful drivers, the researchers hypothesise. Speaking at the Society for Endocrinology meeting, they said: "This study demonstrates that tasks requiring mental flexibility favour women over men, an area previously not considered to elicit strong sex differences. Driving could be an example of how this is applied to everyday life. "Our study suggests that oestrogens may positively influence neuronal activity in the frontal lobes, the area of the brain stimulated by tasks of attention and rule learning, which could explain the female advantage when performing these tasks." (C)BBC

Keyword: Hormones & Behavior; Attention
Link ID: 8125 - Posted: 11.07.2005

By JAMIE SHREEVE FOR a span of some dozen years early in his career, Robert M. Sapolsky, a neurologist and primatologist at Stanford University, spent three or four months a year conducting field research on baboons in Kenya. Over time, he developed an intimate appreciation of the nuances in behavior common to these highly social primates and ourselves. But it was lonely work, and Sapolsky found himself writing scads of letters back home, simply in hopes of getting some mail in return. Thus was forged a zeal for writing in a person with no literary pretension but a great deal to write about. While in two of his previous books for a popular audience, Sapolsky focuses on his own research on the neurobiology of stress ("Why Zebras Don't Get Ulcers") and his life as a scientist ("A Primate's Memoir"), "Monkeyluv," a collection of essays published over the last 10 years in Discover, Natural History, The New Yorker and other magazines, casts a wider net. For the most part, the essays represent what Sapolsky himself describes as "hit-and-run obsessions" - topics that infect his mind for a couple of months, causing him to research endlessly and drive his poor wife to distraction with monologues on the subject until he eventually writes the obsession out of his system, leaving room for the next one. The result of this strategy is mostly a hit. The collection is organized into three sections, each hinging on some Big Question in natural science: the relative influence of genes and environment in determining behavior; how our brains affect our bodies and vice versa; and the way society shapes the individual. Like any good modern biologist, Sapolsky, a MacArthur "genius" award winner, relies in his research on the analytical power of reductionism: the more one divides natural phenomena into their constituent parts, and those parts into subparts and so forth, the more one can learn about how nature really works. As the essays in the first section make clear, however, the notion that the genes at the base of this biological hierarchy determine the workings of everything above them is total nonsense. Copyright 2005 The New York Times Company

Keyword: Genes & Behavior; Evolution
Link ID: 8124 - Posted: 11.07.2005