Bruce Bower There's nothing like a good night's sleep to get some serious thinking done. That, at least, is the theme of two new investigations, one conducted with rodents and the other with people. Rats permitted to explore novel objects display distinctive activity throughout much of their brains. That activity reappears—even more strongly than originally—during a stage of slumber called slow-wave sleep, say neuroscientist Sidarta Ribeiro of Duke University Medical Center in Durham, N.C., and his colleagues. A reprise of waking neural activity during slow-wave sleep—the longest sleep stage in rats and people—promotes recall of novel experiences, the scientists propose. Then, neural changes crucial for memory storage occur during rapid eye movement (REM) sleep, in their view. Copyright ©2004 Science Service

Keyword: Sleep; Learning & Memory
Link ID: 4858 - Posted: 06.24.2010

'Liquid' bridge could help severed nerve cells grow. HELEN R. PILCHER It may well be the smallest scaffolding in the world, and the easiest to set up. Researchers have devised a tiny self-assembling structure that they hope will help repair damaged spinal cords. Every year in the United States alone, about 15,000 people damage their spines. Few recover fully as it is difficult for damaged nerves to grow across the gap in a severed spinal cord. Researchers have tried to build bridges across these gaps, so that nerves can grow. Most of these are made out of a solid material such as collagen, but require invasive surgery that can cause extra trauma to the injury. © Nature News Service / Macmillan Magazines Ltd 2004

Keyword: Regeneration
Link ID: 4857 - Posted: 06.24.2010

In the debate over whether nature or nurture holds greater sway over sexual orientation, the balance has tipped in recent years toward genes and the uterine milieu. Now that notion is dramatically bolstered by an unusual study of children born with malformed genitals. Changing the gender of a newborn through surgery, hormonal therapy, and upbringing doesn't reliably change the gender with which the person ultimately identifies. A rare birth defect called cloacal exstrophy literally turns its victims inside out, and it leaves them with incomplete genitalia. No one knows what causes the condition, but the babies are born with their bladders and intestines hanging out of their body cavity. It hits boys three times more often than girls, and the boys are born with tiny penises. Surgeons can fit the organs back inside, but penile reconstruction is much more difficult. Instead, many surgeons lop off the miniature penis, prescribe estrogen, and advise the parents to raise their child with all the trappings of girlhood. f> Copyright © 2004 by the American Association for the Advancement of Science.

Keyword: Sexual Behavior; Hormones & Behavior
Link ID: 4856 - Posted: 06.24.2010

Brain scan may boost drug development. HELEN R. PILCHER A new test allows researchers to peer into the brains of patients and see the tell-tale protein clumps thought to underlie Alzheimer's disease. The method may help doctors with diagnosis, and should boost disease monitoring and drug development. At present, Alzheimer's disease can be confirmed only after a patient has died. Doctors use cognitive tests and brain scans to assess living patients, and can usually diagnose the disease with about 85% accuracy. But the new technique should help them catch the disease earlier, when potential treatments may work better. "It should allow us to design better clinical trials and show us if new treatments are working," says William Klunk of the University of Pittsburgh School of Medicine, who co-devised the test1. The method, which is pending approval from the US Food and Drug Administration, should be available in the clinic within three to five years, he speculates. © Nature News Service / Macmillan Magazines Ltd 2004

Keyword: Alzheimers; Brain imaging
Link ID: 4855 - Posted: 06.24.2010

GAINESVILLE, Fla. --- It is well known that unborn babies can recognize their mothers' voices and distinguish music from noise. But exactly what they hear remains unclear. Now, scientists at the University of Florida have added a piece to the puzzle. In a series of unique experiments on a pregnant ewe designed to record exactly what sounds reach the fetal ear, UF research has bolstered previous findings suggesting that human fetuses likely hear mostly low-frequency rather than high-frequency sounds. That means they hear vowels rather than consonants and are more sensitive to the melodic parts of speech than to pitch, said Ken Gerhardt, a UF professor of communication sciences and disorders and an associate dean of the Graduate School. As for music, "they're not going to hear the violins, but they will hear the drums," said Gerhardt, who led the research reported in the November-December issue of the journal Audiology and Neuro Otology.

Keyword: Hearing; Development of the Brain
Link ID: 4854 - Posted: 01.23.2004

Are you having trouble keeping that New Year's resolution to get more exercise? As this ScienCentral News video reports, scientists are finding more reasons you should stick to it. We already know that exercise is good for the heart and the body. But now there's more evidence that it's good for the brain too. "Exercise can have effects on your alertness and on your ability to learn and also changes in the brain," says Judy Cameron, a neuroscientist at the Oregon National Primate Research Center run by the Oregon Health and Sciences University. © ScienCentral, 2000-2003.

Keyword: Neurogenesis
Link ID: 4853 - Posted: 06.24.2010

Learning to juggle can cause changes in the brain, scientists have found. Using brain scans, the researchers showed that in 12 people who had learnt to juggle, certain brain areas had grown. But three months later, during which time people stopped juggling, the brain had gone back to its normal size. Writing in Nature, the researchers from the University of Regensburg, Germany, say their findings challenge the view that experiences do not affect the brain. The team studied 24 people who had no juggling ability. They were scanned using voxel-based morphometry, a technique which measures concentrations of brain tissue. (C) BBC

Keyword: Miscellaneous
Link ID: 4852 - Posted: 01.22.2004

Monkeys can understand the simple rules of grammar but the key element of all human languages is beyond them, a study at Harvard University has shown. The research with cotton-top tamarins shows they are able to instinctively understand finite state grammar, involving the simple pairing of words. However, they are not able to follow phrase structure grammar, the complex rules crucial to every human language. Details of the US research are published in the journal Science. "The technique that we used is one that's been long-used by people working with human infants," Harvard's Dr Marc Hauser told BBC World Service's Science In Action programme. "The basic method is that you play [the monkeys] examples of things that... fit the rule that if you have an example from the category A, you will always have, immediately following it, an example after it from the category B." (C) BBC

Keyword: Language
Link ID: 4851 - Posted: 01.22.2004

NewScientist.com news service People who suffer from panic attacks lack a key neurochemical receptor in their brains, say US researchers. Their findings throw light on the molecular mechanisms that predispose a person to anxiety. The study, led by Alexander Neumeister of the Mood and Anxiety Disorders Program at the National Institute of Mental Health in Bethesda, Maryland, is the first to identify a deficit in the 5HT1A receptor in living humans with panic disorder. Similar, but much smaller deficits have also been found in people with depression. The new work follows a study by Rene Hen of Columbia University, New York in 2002, which showed that knockout mice engineered to lack this type of serotonin receptor early in development show signs of anxiety in adulthood. © Copyright Reed Business Information Ltd.

Keyword: Emotions; Stress
Link ID: 4850 - Posted: 06.24.2010

By GARDINER HARRIS Adding to the debate over using antidepressant drugs for depressed teenagers and children, a group of prominent researchers issued a report yesterday saying that Zoloft and similar medicines did not increase children's suicide risk. The group, drawn from members of the American College of Neuro- psychopharmacology, also found that the drugs were effective in treating children's depression. "Depression in children and adults is the major illness that underlies suicide, and we believe that the S.S.R.I. class represents the medication with the greatest efficacy against this very serious condition," said Dr. J. John Mann, a professor of psychiatry at Columbia University who was co-chairman of the reporting panel. Copyright 2004 The New York Times Company

Keyword: Depression
Link ID: 4849 - Posted: 01.22.2004

St. Louis, -- A study led by researchers at Washington University School of Medicine in St. Louis suggests two proteins work together in mice to prevent formation of brain plaques characteristic of Alzheimer's disease. The proteins, apolipoprotein E (apoE) and clusterin, appear to act as "chaperones" orchestrating the clearance of potentially hazardous molecules out of the brain. Ironically, these proteins also have been implicated in a key stage of plaque formation. The study appears in the Jan. 22 issue of the journal Neuron. "This is one of the first demonstrations in living animals that these proteins affect amyloid clearance," says David H. Holtzman, M.D., the Andrew B. and Gretchen P. Jones Professor and head of the Department of Neurology. "Our findings suggest it is worthwhile to explore the use of drugs or therapies to alter or perhaps increase the expression of these proteins as a potential treatment for Alzheimer's disease."

Keyword: Alzheimers
Link ID: 4848 - Posted: 01.22.2004

New Haven, Conn. -- High levels of estrogen may enhance the brain's response to stress, making women more vulnerable to mental illnesses such as depression and post-traumatic stress disorder (PTSD), according to a Yale study. This finding may explain why stress-related mental illnesses occur at least twice as often in women as in men. It also may explain why the discrepancy in prevalence begins in women at puberty, continues through the childbearing years, and then declines in postmenopausal years, said Becca Shansky, a graduate student in neurobiology at Yale School of Medicine and lead author of the study to be published in the March issue of Molecular Psychiatry. The researchers exposed male and female rats to different levels of stress and then tested them on a short-term memory task. The authors found that without stress, males and females performed at the same level. After exposure to high levels of stress, both genders made significant memory errors. However, after exposure to a moderate level of stress, the female rats were impaired, but the males were not, suggesting that females were more sensitive to the effects of stress. Male rats performed the same with moderate stress as they did without any stress.

Keyword: Hormones & Behavior; Stress
Link ID: 4847 - Posted: 01.22.2004

Study shows the value of sleeping on a problem. MICHAEL HOPKIN "Sleep on it" is standard advice to anyone agonizing over a tricky puzzle. A study of mathematical problem-solving has now shown that a good night's rest really does give you a fresh perspective. The discovery lends credence to the popular maxim that sleep stimulates lateral thinking, says Jan Born of the University of Lübeck, Germany, who led the project. Born and his colleagues presented subjects with a series of numbers. They gave participants a simple rule with which to generate a second string of numbers from the first, and asked them to deduce the final digit in this sequence. However, they didn't tell them about a hidden shortcut that allowed the final digit to be calculated almost immediately. © Nature News Service / Macmillan Magazines Ltd 2004

Keyword: Sleep
Link ID: 4846 - Posted: 06.24.2010

Three brain areas of panic disorder patients are lacking in a key component of a chemical messenger system that regulates emotion, researchers at the NIH’s National Institute of Mental Health (NIMH) have discovered. Brain scans revealed that a type of serotonin receptor is reduced by nearly a third in three structures straddling the center of the brain. The finding is the first in living humans to show that the receptor, which is pivotal to the action of widely prescribed anti-anxiety medications, may be abnormal in the disorder, and may help to explain how genes might influence vulnerability. Drs. Alexander Neumeister and Wayne Drevets, NIMH Mood and Anxiety Disorders Program, and colleagues, report on their findings in the January 21, 2004 Journal of Neuroscience. Each year, panic attacks strike about 2.4 million American adults “out of the blue,” with feelings of intense fear and physical symptoms sometimes confused with a heart attack. Unchecked, the disorder often sets in motion a debilitating psychological sequel syndrome of agoraphobia, avoiding public places. Panic disorder runs in families and researchers have long suspected that it has a genetic component. The new finding, combined with evidence from recent animal studies, suggests that genes might increase risk for the disorder by coding for decreased expression of the receptors, say the researchers.

Keyword: Emotions
Link ID: 4845 - Posted: 06.24.2010

WILLIAM McCALL, Associated Press Writer Everybody feels refreshed following a good night's sleep. But can you wake up smarter? More artistic perhaps? German scientists say they have demonstrated for the first time that our sleeping brains continue working on problems that baffle us during the day, and the right answer may come more easily after 8 hours of rest. The German study is considered to be the first hard evidence supporting the common sense notion that creativity and problem solving appear to be directly linked to adequate sleep, scientists say. Other researchers who did not contribute to the experiment say it provides a valuable reminder for overtired workers and students that sleep is often the best medicine. ©2004 Associated Press

Keyword: Sleep
Link ID: 4844 - Posted: 06.24.2010

The only way for smokers to avoid exposure to significant levels of cancer-causing substances is to quit completely, research has found. A team from the University of Minnesota found that smokers who cut their cigarette consumption are exposed to lower amount of a potent carcinogen. However, the drop is not proportional to the reduction in the number of cigarettes smoked. The study is published in the Journal of the National Cancer Institute. Cigarette smoking is the cause of 90% of the world's lung cancer cases - but it is not known whether smokers who reduce the number of cigarettes smoked per day also decrease their risk of lung cancer. The Minnesota team set out to answer this question by measuring the metabolites of a specific tobacco carcinogen in the urine of smokers who were taking part in a programme to cut their consumption. (C) BBC

Keyword: Drug Abuse
Link ID: 4843 - Posted: 01.21.2004

by Gregory A. Leskin, Ph.D., and Javaid I. Sheikh, M.D., M.B.A., Psychiatric Times According to the DSM-IV, panic disorder is classified as an anxiety disorder consisting of repeated and unexpected panic attacks. Panic attacks are defined as discrete events characterized by the sudden onset of cardiorespiratory symptoms and physiological arousal, accompanied by catastrophic fears and the urge to flee. Typically, these symptoms include shortness of breath, tachycardia, nausea, sweating, and fears that the individual is losing control or going crazy. Such spontaneous panic attacks typically reach an apex of intensity within 10 minutes. Data from large scale epidemiological surveys suggest that panic disorder is more common in women than in men (Joyce et al., 1989; Katerndahl and Realini, 1993; Reed and Witchen, 1998). The National Comorbidity Survey (NCS) examined the presence of psychiatric morbidity, including depression, panic disorder and general anxiety, in a large national sample (Kessler et al., 1994). Based on NCS data, Eaton et al. (1994) found that panic disorder is 2.5 times more prevalent among women than men. In addition, the gender difference appears to increase according to age. For example, the prevalence rate of panic disorder for women ages 15 to 24 was 2.5%, compared to 1.3% of same-age men. For older women and men, the overall rates drop, but the difference between genders appears to grow. Among women ages 35 to 44, the rate of panic disorder was 2.1%, compared to the 0.6% rate among same-age men. © 2004 Psychiatric Times. All rights reserved.

Keyword: Emotions
Link ID: 4842 - Posted: 06.24.2010

by Victoria Hendrick, M.D., Psychiatric Times Estrogen and progesterone are believed to play a role in the regulation of mood and well-being. Several mechanisms have been proposed for this effect, including the hormones' influence on monoamine oxidase (MAO) metabolism. Estrogen inhibits MAO, thereby diminishing the degradation of norepinephrine and serotonin and thus increasing their activity, while progesterone has the reverse impact on MAO (Chakravorty and Halbreich, 1997; Luine and Rhodes, 1983). Allopregnanolone, a metabolite of progesterone, is a potent neuroactive steroid that modulates g-aminobutyric acid (GABA) receptors and may be anxiolytic (Majewska et al., 1986). Estrogen's influence on mood has been studied significantly more than that of progesterone. While estrogen's mood-elevating effect is generally acknowledged, the clinical magnitude of this effect remains unclear. Unfortunately, many studies examining this question have been uncontrolled or retrospective or have used populations with only mild levels of depression. A meta-analysis of research done between 1970 and 1995 (mostly involving conjugated equine estrogen [Premarin]) reported moderate-to-large mood-elevating effects from estrogen administration, which diminished following addition of a progestogen (Zweifel and O'Brien, 1997). Interestingly, in this meta-analysis, perimenopausal women appeared more likely to benefit than postmenopausal women. The authors, however, cautioned that methodological shortcomings limited the generalizability of several of the studies.

Keyword: Hormones & Behavior; Depression
Link ID: 4841 - Posted: 01.21.2004

by William Kanapaux, Psychiatric Times On any given day, it is estimated that about 70,000 inmates in U.S. prisons are psychotic. Anywhere from 200,000 to 300,000 male and female prison inmates suffer from mental disorders such as schizophrenia, bipolar disorder and major depression. Prisons hold three times more people with mental illness than do psychiatric hospitals, and U.S. prisoners have rates of mental illness that are up to four times greater than rates for the general population. These are the findings of a report by Human Rights Watch, released Oct. 22, 2003. Many of the statistics cited by the organization have been released by various organizations and agencies, but the 215-page report provides a more complete picture of the U.S. prison system as the nation's primary mental health care facilities. The complete report is available on their Web site at . "Ill Equipped: U.S. Prisons and Offenders with Mental Illness" resulted from two years of research and hundreds of interviews with mental health care experts, prisoners, correction officials and attorneys. It reported that few prisons offer adequate mental health care services and that the prison environment is dangerous and debilitating for prisoners who have mental illness. These prisoners are victimized by other inmates, punished by prison staff for behaviors associated with their illnesses and often placed in highly restrictive cells that exacerbate their symptoms. © 2004 Psychiatric Times. All rights reserved.

Keyword: Schizophrenia
Link ID: 4840 - Posted: 06.24.2010

By REUTERS CHICAGO, — Two drugs that act differently on the brain's chemistry worked in tandem to help stave off the brain-robbing symptoms of Alzheimer's disease, researchers said Tuesday. The patients in a yearlong study were afflicted with moderate-to-severe Alzheimer's and had been taking the drug donepezil, which prevents the breakdown of an important chemical messenger in the brain, acetylcholine, which commonly occurs with Alzheimer's. But patients who also took the drug memantine scored better on tests for cognition and some quality-of-life measures than patients given a placebo along with donepezil. Memantine is a drug that counteracts the overproduction of the brain cell-killing chemical glutamate. Copyright 2004 The New York Times Company

Keyword: Alzheimers
Link ID: 4839 - Posted: 06.24.2010