SAN FRANCISCO, June 21 – Increased levels of the stress hormone cortisol are clearly elevated in child-bearing-aged women who have stopped menstruating – not only in the bloodstream, but also in the cerebrospinal fluid, a senior researcher at the Magee-Womens Research Institute has found. The study is significant because it shows a definitive link between cortisol levels in circulating blood and those in the fluid that surrounds and bathes the brain and spinal cord. "In fact, cortisol levels in the cerebrospinal fluid are even higher than in the circulating bloodstream," said Sarah Berga, M.D., a professor in the departments of obstetrics, gynecology and reproductive sciences and psychiatry at the University of Pittsburgh School of Medicine and a senior investigator at Magee-Womens Research Institute. "This is really important because cortisol is neurotoxic."

Keyword: Hormones & Behavior; Stress
Link ID: 2263 - Posted: 06.24.2010

Seek glimpse into why amputees 'feel' what isn't there By Randy Dotinga HealthScoutNews Reporter HealthScoutNews) -- Scientists are getting a glimpse into how the brain creates a phantom limb, potentially helping them develop new ways to treat amputees who feel pain in body parts that aren't there. In a very unusual case involving a stroke victim's perception of a third arm, researchers at the University of California at San Francisco found activity in a part of the brain that sends signals to the body, not the other way around. That suggests the brain's mental image of the body may play a key role in the development of phantom limbs, says Dave McGonigle, a radiology researcher and co-author of a study that appears in the current issue of Brain. Copyright © 2002 ScoutNews, LLC. All rights reserved.

Keyword: Pain & Touch; Stroke
Link ID: 2262 - Posted: 06.24.2010

SHARON BEGLEY, The Wall Street Journal It wasn't the kind of passage you usually encounter in a strait-laced science journal: "I have had to spend periods of several weeks on a remote island in comparative isolation," Anonymous wrote in Nature. Curiously, he continued, the day before he was due for shore leave his beard grew noticeably: "I have come to the conclusion that the stimulus for (this) growth is related to the resumption of sexual activity." Neither Anonymous nor his fellow scientists were surprised that the aforementioned activity would loose a flood of testosterone, which affects beards the way Miracle-Gro affects tomato plants. No, the weird part is that merely anticipating female companionship did the trick. Just as stress in the med students I wrote about last week altered the expression of genes in their immune systems, so libidinous thoughts seem to affect gene expression, says developmental psychologist David Moore of Pitzer College in Claremont, Calif. Thoughts can cause the release of hormones that can bind to DNA, "turning genes `on' or `off.' " ©2002 Associated Press

Keyword: Genes & Behavior
Link ID: 2261 - Posted: 06.24.2010

By Helen Briggs BBC News Online science reporter Professional musicians have more grey matter in a part of the brain involved in processing music, scientists have found. The discovery could explain why musical virtuosos tend to be born not made. But it is unlikely to resolve the long-running debate about what makes a potential Mozart. Repeated flexing of the brain by practising a musical instrument could account for the extra grey matter in the auditory cortex. The latest twist in the search for a scientific basis of musical ability was made by a team at the University of Heidelberg in Germany. Neurologists played tones of varying frequencies to professional musicians, amateur musicians and non-musicians, and then recorded their brain responses. (C) BBC

Keyword: Hearing
Link ID: 2260 - Posted: 06.22.2002

Almost one in three people with Parkinson's disease suffer from sleep attacks causing them to fall asleep suddenly. A study by doctors in Austria has concluded that the attacks, which have been the subject of controversy, actually do exist. They concluded that the attacks which can happen at any time are caused by the medication taken by patients to alleviate symptoms of the disease. As yet, there is no way of predicting, preventing or treating the attacks. Dr Carl Nikolaus Homann and colleagues at the Karl Franzens University Hospital in Graz, Austria, reviewed studies of 124 patients with Parkinson's disease. They found that 30% had suffered at least one sleep attack. (C) BBC

Keyword: Parkinsons; Sleep
Link ID: 2259 - Posted: 06.21.2002

Exclusive from New Scientist Print Edition The sweet scent of roses or almonds could take some of the pain out of your stay in hospital. But only if you're a woman. Serge Marchand and Pierre Arsenault at the University of Québec in Abitibi-Témiscamingue asked 20 men and 20 women to keep their hand immersed in painfully hot water for as long as they could while smelling various odours. When given pleasant aromas such as almond extract to sniff, the women experienced significantly less pain. Foul smells such as vinegar seemed to slightly intensify their pain. However, the pain felt by the men was not affected by the smells. Both sexes reported feeling happier in the presence of good smells, while bad smells put them in a worse mood. But this effect on the emotions can't be what changed the women's perception of pain. If it was, the men should have responded in the same way. © Copyright Reed Business Information Ltd.

Keyword: Chemical Senses (Smell & Taste); Pain & Touch
Link ID: 2258 - Posted: 06.24.2010

By Eric Haseltine If a stroke robbed you of your visual cerebral cortex (the back of your brain), you'd no longer be able to see. But you wouldn't be blind, strictly speaking, because you'd still be able to unconsciously orient yourself toward visual stimuli and even make your way across a cluttered room without bumping into anything. Such blindsight is made possible by a primitive visual pathway (sometime called the "where" pathway) that controls behavior without conscious vision. You've experienced blindsight if you've ever reflexively reached for a ball suddenly thrown at you. Open your hand as if you were about to pick up one of these silver dollars to experience another example of this mysterious ability. Notice that you automatically opened your fingers wider than if you had reached for one of the dimes. © Copyright 2002 The Walt Disney Company.

Keyword: Vision; Pain & Touch
Link ID: 2257 - Posted: 06.24.2010

By NICHOLAS WADE Scientists working with human embryonic stem cells have converted them into the type of brain cell that is lost in Parkinson's disease, and have shown that the equivalent cells in mice alleviate Parkinson-like symptoms in rodents. "What we are showing here is that we absolutely, definitely have the right cell," said Dr. Ron McKay, a stem cell biologist who works at the National Institutes of Health. The cells produce a neuron-to-neuron signalling chemical called dopamine. The loss of dopamine is believed to cause many of the symptoms of Parkinson's disease. Dr. McKay hopes that the cells he has developed will one day be used to treat the disease, after he has spent two years testing how they work in monkeys. Indeed a surgeon could put them in patients quite quickly "but they wouldn't know what they have done," Dr. McKay said. Copyright 2002 The New York Times Company

Keyword: Parkinsons; Stem Cells
Link ID: 2256 - Posted: 06.21.2002

Using brain cells from rats, scientists at The Johns Hopkins University School of Medicine and the University of Hamburg have manipulated a molecular "stop sign" so that the injured nerve cells regenerate. While their findings are far from application in people, the prospects for eventually being able to repair spinal cord injury are brighter, they say. "Four thousand years ago, physicians wrote that spinal cord injury was untreatable, and unfortunately it's much the same today," says Ronald L. Schnaar, Ph.D., professor of pharmacology and of neuroscience at Hopkins. "But the basic-science framework for improving this situation is quickly emerging."

Keyword: Regeneration; Development of the Brain
Link ID: 2255 - Posted: 06.21.2002

From The Economist print edition Researchers can now watch the brain as memories are stored within it BEFORE a big exam, a sound night's sleep will do you more good than poring over your textbooks. That, at least, is the folk wisdom. And science, in the form of behavioural psychology, supports that wisdom. But such behavioural studies cannot distinguish between two competing theories of why sleep is good for the memory. One says that sleep is when permanent memories form. The other says that they are actually formed during the day, but then “edited” at night, to flush away what is redundant. To tell the difference, it is necessary to peer into the brain of a sleeping person, and that is hard. But after a decade of painstaking work, a team led by Pierre Maquet of the Cyclotron Research Centre at Liège University in Belgium has managed to do it. Dr Maquet and his colleagues have persuaded enough people to fall asleep inside a noisy, cramped brain-scanning machine to collect the evidence needed to show what is happening. Steven Laureys, one of Dr Maquet's collaborators, revealed their results to a meeting of the Organisation for Human Brain Mapping in Sendai, Japan, earlier this month. Copyright © 2002 The Economist Newspaper and The Economist Group. All rights reserved.

Keyword: Learning & Memory; Sleep
Link ID: 2254 - Posted: 06.24.2010

UPTON, NY — The idea that obese people eat too much because they find food more palatable than lean people do has gained support from a new brain-imaging study at the U.S. Department of Energy’s Brookhaven National Laboratory. The study reveals that the parts of the brain responsible for sensation in the mouth, lips, and tongue are more active in obese people than in normal-weight control subjects. “This enhanced activity in brain regions involved with sensory processing of food could make obese people more sensitive to the rewarding properties of food, and could be one of the reasons they overeat,” said Brookhaven physician Gene-Jack Wang, lead author of the study. Wang acknowledges that obesity is a complex disease with many contributing factors, including genetics, abnormal eating behavior, lack of exercise, and cultural influences, as well as cerebral mechanisms, which are not yet fully understood. In a recent study, he and his team found that obese people have fewer brain receptors for dopamine, a neurotransmitter that helps produce feelings of satisfaction and pleasure, implying that obese people may eat to stimulate their underserved reward circuits, just as addicts do by taking drugs.

Keyword: Obesity; Brain imaging
Link ID: 2253 - Posted: 06.24.2010

Denied sugar, bingeing rats suffered withdrawal It's a common refrain: "I'm addicted to sugar." Now a study by Princeton University psychologists suggests that such urges really may be a form of addiction, sharing some of the physiological characteristics of drug dependence. Although the term "sugar addiction" often appears in magazines and on television, scientists had not demonstrated that such a thing as sugar dependency really exists, said neuroscientist Bart Hoebel, who led the study. Hoebel and colleagues studied rats that were induced to binge on sugar and found that they exhibited telltale signs of withdrawal, including "the shakes" and changes in brain chemistry, when the effects of the sweets were blocked. These signs are similar to those produced by drug withdrawal. Sugar, said Hoebel, triggers production of the brain's natural opioids. "We think that is a key to the addiction process," he said. "The brain is getting addicted to its own opioids as it would to morphine or heroin. Drugs give a bigger effect, but it is essentially the same process."

Keyword: Obesity; Drug Abuse
Link ID: 2252 - Posted: 06.21.2002

Copyright © 2002 United Press International BALTIMORE, - Scientists announced Wednesday they have figured out a new way to get nerve cells to regenerate in the laboratory and have come one step closer to being able to repair spinal cord injuries - although that prospect remains years away. "For the first time in history there is some optimism that we may be able to get functional recovery of spinal cord injuries," Ronald L. Schnaar, co-author of the study and professor of pharmacology and of neuroscience at Johns Hopkins University, told United Press International. "Whether it's this decade or next decade, I think we'll begin to see this knowledge turned into therapies." Schnaar and colleagues at the University of Hamburg, Germany, discovered how to modulate a molecular signal that inhibits the regeneration of nerve cells after they are damaged. Copyright © 2001 Nando Media

Keyword: Regeneration; Brain Injury/Concussion
Link ID: 2251 - Posted: 06.24.2010

BY FAYE FLAM Knight Ridder Newspapers PHILADELPHIA - (KRT) - A scan of brain activity may reveal aspects of one's personality, scientists said Thursday, raising both the possibility of new treatments for mental illness and the specter of Orwellian "thought police." In a report published Friday, researchers said they can roughly distinguish loners from social butterflies by putting them under brain-scanning equipment and showing them pictures of happy faces. The more extroverted the test subject, the more brain structures seemed to light up at the sight of a smiling person. © 2002, The Philadelphia Inquirer.

Keyword: Brain imaging; Emotions
Link ID: 2250 - Posted: 06.24.2010

The controversy surrounding stem cell research—in particular whether the cells should come from embryonic sources or adult ones—hinges on what, exactly, cells from the two sources are capable of. Embryonic stem cells, which are more politically contentious because they must be harvested from human embryos, can differentiate into any tissue in the human body. Adult stem cells, although available from less controversial sources, have so far shown less plasticity than their embryonic counterparts. Now the results of two studies published online by the journal Nature provide additional insight into the abilities of both classes of stem cells. The findings further suggest that only by investigating the two kinds of stem cells will it be possible to determine which source will prove most useful in treating a particular disease. Catherine Verfaillie and of the University of Minnesota Stem Cell Institute and her colleagues report that a particular kind of adult stem cell, derived from bone marrow and dubbed a multipotent adult progenitor cell (MAPC), can differentiate into nearly all types of mouse tissue. The scientists injected MAPCs into mice blastocysts (embryos comprised of approximately 100 cells), which were then transferred to foster mothers for gestation. The resultant animals exhibited multiple tissue types, including brain, lung, retina, spleen and skin, attributable to the MAPCs. "Some of the animals are 40 percent derived from the bone marrow stem cells, suggesting that the cells contribute functionally to a number of organs," Verfaillie notes. "This is similar to what one would expect of [embryonic stem] cells." The team next injected MAPCs into a living animal and found that the cells still differentiated into liver, intestine and lung tissue, but overall MAPCs were detected in fewer tissue types than in the blastocyst-injected mice. © 1996-2002 Scientific American, Inc. All rights reserved.

Keyword: Stem Cells; Parkinsons
Link ID: 2249 - Posted: 06.24.2010

Even short-term use of ecstasy can damage the memory, researchers have found. A study by scientists at the University of Cambridge and the University of East London in the UK showed ecstasy users performed worse in tests than people who used other drugs. The researcher who led the study said her findings, and other evidence about long-term problems caused by ecstasy use, meant the drug should not be reclassified from Class A to Class B, as a Home Office committee has suggested. But campaigners for DrugScope said it was hard to determine whether the results of this and other similar studies were significant. (C) BBC

Keyword: Learning & Memory; Drug Abuse
Link ID: 2248 - Posted: 06.21.2002

Secretion of a stress hormone called cortisol and activation of the sympathetic nervous system are components of the classic "fight or flight" response to danger. A common source of cortisol release and increased cardiovascular activity is public speaking. A study in the June issue of Alcoholism: Clinical & Experimental Research builds upon previous work by comparing the cardiovascular responses of alcoholics and nonalcoholics to the psychological challenge of public speaking in relation to the physical challenge of standing (orthostasis). "Since cortisol is central to our ability to handle stress," said William R. Lovallo, Director of the Behavioral Sciences Laboratories at the Veterans Affairs Medical Center, Oklahoma City and corresponding author for the study, "we were surprised several years ago when we found that patients with alcohol dependence had cortisol responses that were absent or greatly attenuated. It didn't matter if the patient was asked to hold a hand in ice water, squeeze a hand-exercise device until it hurt, do mental arithmetic problems, or perform in a public-speaking simulation. Due to this cortisol response deficit, we suspected that these patients might also have a reduced fight or flight response. Most persons see public speaking as socially threatening, and they respond with the primitive fight or flight mechanism." Before testing alcoholics for their responses to a public-speaking task, researchers first needed to establish if their sympathetic nervous system was able to respond at all. "This would tell us if their blunting was specific to psychological stressors like public speaking," said Lovallo, "or due to a generalized autonomic deficit."

Keyword: Drug Abuse; Stress
Link ID: 2247 - Posted: 06.21.2002

Because people recognize the same emotions across languages and cultures, psychologists have long suspected that a person's ability to perceive basic emotions is innate. However, a new study published in the June 18 early edition of the Proceedings of the National Academy of Sciences suggests that experience can alter the way people see emotions. Led by University of Wisconsin-Madison psychologist Seth Pollak, the study examined how children categorize facial expressions as happy, sad, angry or fearful based on one particular emotional experience - physical abuse. Studying children who had been abused, Pollak says, offered an opportunity both to examine the effects of atypical experience on how children think about emotions and to possibly identify new interventions that could help abused children more effectively manage resulting behavioral problems. For this study, Pollak invited both abused and non-abused children, 8 to 10 years old, to his Child Emotion Research Laboratory. There, they played computer "games" that presented digitally morphed photos of facial expressions that ranged from either happy to fearful, happy to sad, angry to fearful or angry to sad. While some of the faces expressed a single emotion, most were blends of two emotions.

Keyword: Emotions
Link ID: 2246 - Posted: 06.21.2002

By ANNE EISENBERG IN the 2001 movie "Memento," the hero cannot hold onto any new memories. He forgets whatever he sees or hears within moments, distracted by new events that he also forgets in turn. Profound amnesia like this comes about in real life, too, from trauma or disease to the hippocampus, the cortical section of the brain where memories are formed. One day, though, a computer chip may do some of the work of a damaged hippocampus, replacing living neurons with silicon ones. That is the goal of Dr. Theodore W. Berger, a professor of biomedical engineering at the University of Southern California in Los Angeles and the director of the Center for Neural Engineering there. Dr. Berger has spent the past decade developing some of the basics for a chip-assisted hippocampus. Copyright 2002 The New York Times Company

Keyword: Learning & Memory; Robotics
Link ID: 2244 - Posted: 06.21.2002

A woman who lost nearly three stone in 11 months suffered a brain illness normally associated with alcoholics. Her condition mystified doctors because she insisted she was on a healthy, balanced, diet throughout. Doctors say that either her own genetic makeup - or perhaps the herbal diet supplement she was taking might be to blame. The 30-year-old, who was 11.5 stone before she began dieting, developed a condition called Wernicke's encephalopathy. Wernicke's encephalopathy usually develops suddenly, and involves involuntary, jerky eye movements or paralysis of muscles moving the eye, coupled with poor balance, staggering gait or inability to walk. When the condition, caused by a severe lack of vitamin B1, is diagnosed, doctors normally link it to heavy drinking. (C) BBC

Keyword: Anorexia & Bulimia
Link ID: 2243 - Posted: 06.11.2002