Nerve cells need cholesterol to establish contacts / New perspectives for the treatment of brain lesions A previously unknown role of cholesterol in the formation of contacts between nerve cells has been discovered by researchers at the Max-Delbrück-Center for Molecular Medicine in Berlin, Germany, and at the Centre de Neurochimie in Strasbourg in France (Science, November 09th, 2001). Their results suggest a link between brain cholesterol metabolism and nerve cell development, learning and memory and hint at new strategies to cure injury- or disease-induced brain lesions. Brain function depends on the exchange of electrical signals between nerve cells that is mediated by highly specialized contact sites, the socalled synapses. Their formation is a decisive phase during brain development and plays an important role in learning and memory. So far, however, the mechanisms of this process are largely obscure and thus, their elucidation is therefore an important topic of neuroscience research. Moreover, the identification of "synaptogenic" factors is a fundamental prerequisite to repair synaptic connections that have been destroyed by injury, stroke or neurodegenerative diseases like Alzheimer's.

Keyword: Development of the Brain
Link ID: 966 - Posted: 11.09.2001

Copyright © 2001 Christian Science Monitor Service By LORI VALIGRA, Christian Science Monitor. - It's an underwater nightclub scene that could drown out the overtures of even the most virtuosic terrestrial Romeo. To the human ear, the relentless rat-a-tat-tat of the male cusk eel and the hours-long humming of the midshipman fish may sound like downtown street noise. But to potential mates, these underwater troubadours are the piscine versions of Tony Bennett and Frank Sinatra, crooning love songs in the moonlight. Although whale song has long been documented in ships' logs, it wasn't until World War II that scientists and the military first noticed the sounds of fish and the snapping of crustaceans. So far, more than 700 species of saltwater and freshwater fish throughout the world are known to vocalize, but scientists say the total number is likely much higher. Most of the time, the sounds come from male fish during mating. Copyright © 2001 Nando Media

Keyword: Animal Communication; Sexual Behavior
Link ID: 964 - Posted: 11.09.2001

Viewing attractive female faces activates the brain's reward circuits in males From ancient mythology to modern advertising, the face of a beautiful woman has been regarded as a powerful motivator of men's behavior. Now a group of researchers based at Massachusetts General Hospital (MGH) has shown that, while heterosexual men recognize attractiveness in both female and male faces, they will expend effort to increase their viewing of attractive female faces only. The research also shows that areas of the brain previously identified as responding to such rewards as food, drugs and money also respond to facial beauty. The study appears in the November 8 issue of Neuron. "Our group has been studying the physiological mechanisms that underlie a variety of motivated behaviors," says Hans Breiter, MD, of the Motivation and Emotion Neuroscience Center in the MGH Department of Radiology, the paper's author and leader of the research team. "While many neuroscientists have been studying the visual processing of faces, we wanted to find out if watching beautiful faces can itself be rewarding and can activate the brain's motivation centers." To answer these questions, the researchers conducted three experiments with groups of young, heterosexual men. (Men were chosen as study subjects because other recent research has shown that women's response to facial stimuli can change during their menstrual cycles.) Each experiment utilized a series of 80 photographs of faces that fell into four standard categories: beautiful females, average females, beautiful males, and average males.

Keyword: Sexual Behavior; Brain imaging
Link ID: 963 - Posted: 11.09.2001

In the November 1, 2001 issue, the Journal of Neuroscience inaugurated a new series of critical minireviews called "New Directions in Neuroscience," meant to help readers stay in touch with new methods and new fields of research (Shepherd, 2001). The first set of minireviews is entitled "Genomics and Proteomics," and three of the five reviews treat topics relevant to biological psychology.

Keyword: Genes & Behavior; Newsletter
Link ID: 962 - Posted: 11.09.2001

For almost thirty years there have been two competing hypotheses about how synaptic vesicles discharge transmitter molecules into the synapse and then are recycled for further activity. Recent experiments and reviews indicate that both hypotheses are correct, each applying to a different pool of vesicles within the presynaptic terminal (Richards, Guatimosin, and Betz, 2000; Wilkinson and Cole, 2001).

Keyword: Miscellaneous; Newsletter
Link ID: 961 - Posted: 11.09.2001

Schizophrenia typically has its onset in late adolescence or early adulthood, but cases that occur in childhood or early adolescence appear to be clinically and neurobiologically similar to later-onset illness. Early-onset schizophrenia may offer special opportunities to study how the disease develops and may help to discover its causes. For this reason, a team of neuroscientists (Thompson et al., 2001) used MRI to map, over a five-year period, the brains of 12 patients, 6 male and 6 female, with childhood-onset schizophrenia (COS), and a parallel group of 12 healthy adolescents. A third group of subjects were controls for medication; these were 10 non-schizophrenic adolescents who exhibited chronic mood disturbance and lack of behavioral control for which they were being treated with the same medications as the COS patients. MRI scans were first taken when the subjects were about 13.5 years old, then again about 2.5 years later, and finally about 5 years after the first scans.

Keyword: Schizophrenia; Newsletter
Link ID: 960 - Posted: 11.09.2001

In Figure 8.11 (b and c), we saw that when a finger is denervated or lost, adjacent intact parts of the hand take over its representation in somatosensory cortex. When a hand is lost, the cortical regions that represent the upper arm and face expand, taking over the cortical area that previously represented the missing hand (Figure 8.12). Similar changes occur in the motor cortex after loss of a hand.

Keyword: Regeneration; Newsletter
Link ID: 959 - Posted: 11.09.2001

SAN FRANCISCO--The Pavarottis of the canary world can drive a female wild by singing certain special notes. Now scientists have learned what makes these "sexy syllables" so alluring: Virtuoso canary singers have mastered a tricky vocal technique, which may indicate their overall robustness. Birds sing to attract mates. But why females prefer a particular song has been a puzzle. Although there's evidence that complex and frequent songs are more attractive, a recent idea suggests that certain notes are the key to seduction. "Sexy syllables" in canary song were first identified in 1995 by ethologists Eric Vallet and Michel Kreutzer of the Université de Paris X in Nanterre, France. When males sang certain trills, or when the trills were played on tape, caged females assumed postures inviting copulation. Copyright © 2001 by the American Association for the Advancement of Science.

Keyword: Animal Communication; Language
Link ID: 955 - Posted: 11.08.2001

Three antioxidant compounds that can traverse the blood-brain barrier appear to prevent the damage wrought by so-called free radicals, highly reactive compounds suspected to be involved in aging. The molecules prevent brain damage and prolong life in mice whose natural system to mop up free radicals was knocked out, according to a new study--and researchers are hopeful they could lead to drugs to increase human life-span. Free radicals--oxygen-containing molecules that zap cellular machinery--are churned out whenever an organism transforms food into fuel. If they linger, they cause disease and perhaps aging as well. Creatures neutralize free radicals with an arsenal of enzymes, including mitochondrial superoxide dismutase (SOD2). SOD2 is crucial: Mice lacking it die within days of birth. A synthetic antioxidant called MnTBAP can delay their demise. But MnTBAP can't cross the blood-brain barrier, so mutant mice still develop neurological symptoms; researchers usually have to kill them within 3 weeks. Copyright © 2001 by the American Association for the Advancement of Science.

Keyword: Alzheimers; Neurotoxins
Link ID: 954 - Posted: 11.08.2001

(SAN DIEGO, CALIF.)– As a part of the inaugural International Meeting for Autism Research (IMFAR) conference, four prominent autism scientists will identify the current level of understanding in the areas of genetics, neuroscience, the incidences (or epidemiological trends) and diagnosis of autism and present a look at where the fields are headed. IMFAR will hold its first conference on Nov. 9 and 10 to promote communication and facilitate interdisciplinary collaboration among scientists researching the disorder. "We have brought together some of the pre-eminent researchers who understand the challenge that autism presents," said David G. Amaral, Ph.D., professor of psychiatry at UC Davis School of Medicine and research director at the UC Davis M.I.N.D. Institute, one of the sponsors of the IMFAR conference. "These speakers will challenge their peers to go beyond that foundation and to further expand our current level of understanding of this disorder."

Keyword: Autism
Link ID: 953 - Posted: 06.24.2010

Research on components of the brain's electrical signaling system has answered a basic question about our human evolution, confirming scientific belief that we two-legged, computer-using creatures are descended from prokaryotes -- cellular organisms so primitive and simple that they exist without nuclei or cell walls. The study, led by Zhe Lu, MD, PhD, an Associate Professor in the Department of Physiology at the University of Pennsylvania School of Medicine have been recently published in the journal Nature. The research by Lu and his colleagues focused on the structure and function of molecules called potassium channels, which are essential to how the brain works. When potassium channels open and close, they control the flow of potassium ions across cell membranes. The current contributes to the electrical signals in nerve, muscle and endocrine cells.

Keyword: Evolution
Link ID: 952 - Posted: 11.08.2001

LONDON, England (Reuters) -- Sheep, like turkeys and ostriches, are not considered the most intelligent animals but British scientists say humans may have underestimated the woolly creatures. They could be much smarter than we think. Researchers at the Babraham Institute in Cambridge, southern England, have shown that the animals have a remarkable memory system and are extremely good at recognising faces -- which they suspect is a sure sign of intelligence. Copyright 2001 Reuters. All rights reserved. This material m ay not be published, broadcast, rewritten, or redistributed. © 2001 Cable News Network LP, LLLP.Sheep shun dumb image

Keyword: Evolution; Vision
Link ID: 951 - Posted: 11.08.2001

Our brains use angular measurements to decide how far away objects are. ERICA KLARREICH Even if trigonometry wasn't your strong suit in school, your brain uses it constantly. You judge distance by measuring the angle between the ground and your line of sight to an object, a new study shows. The finding could improve the design of robots and artificial vision systems1. Volunteers who looked through prisms that increased this angle thought objects were closer than they really were, missing them when throwing beanbags or trying to walk to them blindfolded. 1.Ooi, T. L. et al. Distance determined by the angular declination below the horizon. Nature, 414, 197 - 200, (2001). © Nature News Service / Macmillan Magazines Ltd 2001

Keyword: Vision; Robotics
Link ID: 950 - Posted: 11.08.2001

Anti-inflammatory drugs stop protein clumps forming in degenerative brain disease. TOM CLARKE More evidence is emerging that over-the-counter painkillers such as ibuprofen could form the basis of future treatments for Alzheimer's disease. A new study suggests that some non-steroidal anti-inflammatory drugs (NSAIDs) block a process thought to cause the degenerative brain disease. In mice and in cultured human cells, certain NSAIDs prevent a harmful variety of a protein called amyloid from forming - instead the cells produce another amyloid. Many believe that Alzheimer's results when clumps - called plaques - of the harmful amyloid accumulate in the brain. 1.Weggen, S. et al. A subset of NSAIDs lower amyloidogenic Aß42 independently of cyclooxygenase activity. Nature, 414, 212 - 216, (2001). © Nature News Service / Macmillan Magazines Ltd 2001

Keyword: Alzheimers
Link ID: 949 - Posted: 11.08.2001

Without Adverse Effects of Anti-Inflammatory Drugs Researchers at the University of California, San Diego (UCSD) School of Medicine and the Mayo Clinic, Jacksonville, FL have shown in cell cultures and mice that certain nonsteroidal anti-inflammatory drugs (NSAIDs) use a novel mechanism to decrease the harmful amyloid-beta 42 protein (AB42) that forms brain plaques, a hallmark condition in Alzheimer's disease patients. Although some individuals who chronically take NSAIDs have shown reduced risk of developing Alzheimer's disease, the mechanism of action of these drugs is unclear. NSAIDs are known to inhibit master enzymes called cyclooxygenases (COX), which control inflammatory responses. It therefore has been assumed by many researchers that NSAIDs are effective in Alzheimer's disease by reducing toxic, inflammatory process in the brain. However, the new findings, published in the Nov. 8, 2001 issue of the journal Nature, suggest that NSAID therapy has a direct impact on the cause of the disease, which is believed to be the abnormal deposition of AB42 in the brain.

Keyword: Alzheimers
Link ID: 948 - Posted: 11.08.2001

- Each day, we use our noses to help make sense of our surroundings. We may not be as dependent on our olfactory capabilities as dogs or mice, but we are able to recognize and "assign an odor" to many thousands of chemicals in our environment. These chemicals, called odorants, are detected in the nose by roughly 1,000 different odor receptors. Understanding how signals from those receptors are arranged in higher regions of the brain to yield diverse odor perceptions has been a longstanding goal for researchers. Now, researchers have taken a step toward that goal with a series of experiments that shows how signals from different odor receptors are arranged in the brain's olfactory cortex. The findings provide new insights into the processes that underlie odor perception. ©2001 Howard Hughes Medical Institute

Keyword: Chemical Senses (Smell & Taste)
Link ID: 947 - Posted: 11.08.2001

By ANNE RUETER, NEWS STAFF REPORTER A lot of baby boomers who read the news were glad: When scientists at the Salk Institute placed older rats in a stimulating environment, the rats' brains sprouted new neurons. Other aging experts are touting exercise and a healthy diet as ways to keep our minds nimble. But no one hoping to dodge time's tolls should get too euphoric. Sixty-year-old minds don't work like 20-year-old minds. In fact, 25-year-olds are already past their peak in performing certain mental tasks, although they don't notice it, says Denise Park, a psychologist who heads the University of Michigan Center for Aging and Cognition, part of the Institute for Social Research

Keyword: Learning & Memory; Development of the Brain
Link ID: 946 - Posted: 11.08.2001

By discovering how a gene called PTEN influences the growth, proliferation and death of stem cells in the brain, scientists at UCLA's Jonsson Cancer Center have taken an important first step toward unraveling the mysteries of brain development and why some brain cells replicate uncontrollably, giving rise to brain tumors and other brain diseases. Understanding how PTEN works in the brain also is expected to shed light on how stem cells in other parts of the body develop abnormally and may contribute to tumor development in other organs. The findings are described in an article posted Nov. 1 in the journal Science as part of the journal's Science Express Web site, http://www.sciencexpress.org.

Keyword: Stem Cells; Genes & Behavior
Link ID: 943 - Posted: 11.07.2001

How speakers select appropriate words and prepare them for articulation. Core operations in normal speech production are the accessing of words in memory that appropriately express the intended message, and the preparation of each word retrieved for articulation. The theory developed in the Max Planck Institute for Psycholinguistics, Nijmegen, The Netherlands, provides a detailed account of both mechanisms (PNAS, 98, 23, November 06, 2001). Every normal person learns to speak, and speaking involves, among other things, producing words. By reaching adulthood a speaker in our Western culture may well have produced some 50 million words. There is hardly any other human skill that is so well practiced. In normal speech we produce words at rates of some 2 to 4 per second. These words are continuously selected from a mental lexicon containing tens of thousands of words. Still, we make few errors. On average, we select the wrong word (for instance left when we mean right) no more than once in a thousand items. How is this robust, high-speed mechanism organized?

Keyword: Language
Link ID: 941 - Posted: 11.07.2001

By Anita Manning, USA TODAY A diagnostic technique used to find brain tumors or to locate the origin of seizures can accurately detect Alzheimer's and other degenerative brain diseases even before symptoms begin, a study says. Positron emission tomography, or PET scans, which provide 3-D images of brain activity, also can reliably rule out dementia for patients, at least in the three years after the scan, says Daniel Silverman, head of the Neuronuclear Imaging Research Group at the University of California-Los Angeles School of Medicine. By screening patients with PET, he says, an accurate diagnosis can be made sooner than it might have been, and drug therapy can begin promptly. © Copyright 2001 USA TODAY, a division of Gannett Co. Inc.

Keyword: Alzheimers; Brain imaging
Link ID: 940 - Posted: 11.07.2001