By Lauran Neergaard THE ASSOCIATED PRESS WASHINGTON - It's one of the biggest frustrations in treating multiple sclerosis: Someone with debilitating symptoms can have an MRI scan of the brain that, inexplicably, shows only a tiny spot of damage. A Duke University scientist calls that spot the tip of the iceberg - with the discovery that MS patients actually can have 2˝ times more damage there than the regular MRI detected, plus more hidden abnormalities lurking elsewhere. A new scan that adds just 10 minutes to a standard MRI uncovered the trouble, tracking damage building deep in the brain by measuring how water flows through nerve fibers.

Keyword: Multiple Sclerosis; Brain imaging
Link ID: 3359 - Posted: 01.28.2003

Even a minor oxygen shortage at the time of birth may place a premature baby at higher risk of learning problems later on, say researchers. It has been known for a long time that babies born early may not score as highly as full-term babies in intellectual and language tests, at least in the first few years of life. The premature baby's brain is immature, and may be less able to protect itself from a shortage of oxygen. However, while severe oxygen deprivation around the time of birth is clearly linked to brain injury, the impact of more subtle deprivation is less well understood. The small-scale study, from two universities in the US, aimed to provide some answers by comparing the progress of two sets of premature babies - all born at or before 36 weeks - based on a test taken in the first few hours after birth. This measures the acid levels of the blood, and higher levels are a good indicator that the baby has been starved of oxygen at some point during delivery. (C) BBC

Keyword: Development of the Brain
Link ID: 3358 - Posted: 01.27.2003

Using newly developed imaging techniques, UCLA neuroscientists for the first time have "unfolded" the brain's sea-horse-shaped hippocampus to reveal how dynamic activity within the brain structure's complex architecture orchestrates memory formation. Details appear in the Jan. 24 edition of the peer-reviewed journal Science. The researchers used extremely high-resolution functional magnetic resonance imaging (fMRI) and software developed at UCLA's Ahmanson-Lovelace Brain Mapping Center to study blood flow within the hippocampus as 10 human volunteers learned to associate names with faces. The study identified areas within the hippocampus -- the cornu ammonis and the dentate gyrus -- as highly active only during encoding of the face-name pairs. This activity decreased as associations were learned. The subiculum, another area of the hippocampus, was active primarily during the retrieval of the face-name associations. Activity in the subiculum also decreased as retrieval became more practiced.

Keyword: Learning & Memory; Brain imaging
Link ID: 3357 - Posted: 01.27.2003

By SABRA CHARTRAND VIAGRA, the drug that used professional athletes and a retired senator to become a household word, may soon have a counterpart for women. A pharmaceutical company has patented a topical cream as a treatment for a condition it calls female sexual arousal disorder. If sexual dysfunction among women does not yet have a universal name, it is because the phenomenon has only recently caught the attention of the medical establishment. The elimination of taboos on male impotence, and the economic success of Viagra, have helped with that. Now most pharmaceutical companies see a huge potential market for drugs for women, and are racing to develop them. In 1999, The Journal of the American Medical Association reported that 43 percent of women between 18 and 54 had experienced some sort of sexual dysfunction. That number includes women with known physical ailments that can affect sexual function, like heart disease or hormone imbalances. In fact, part of the problem for researchers is reaching a definition of female sexual dysfunction — but they are eager to do so because some anticipate a $6-billion-a-year market. Still, it may be several years before treatments for women appear on drugstore shelves. Copyright 2003 The New York Times Company

Keyword: Sexual Behavior
Link ID: 3356 - Posted: 06.24.2010

Second-rate males exploit female confusion. JOHN WHITFIELD By hanging around with good-looking birds, less macho males get to mate with choosy but confused females, say Australian ecologists. Each breeding pair of superb fairy-wrens (Malurus cyaneus) shares its territory with up to four subordinate males. These birds were thought to help raise chicks and defend the home. Their real motives, it now seems, might be less noble. "So-called helpers can in fact be reproductive parasites," says Michael Double of the Australian National University in Canberra1. © Nature News Service / Macmillan Magazines Ltd 2003

Keyword: Sexual Behavior; Evolution
Link ID: 3355 - Posted: 06.24.2010

Infusing cultured brain tissue slices with the electrical activity of living brains sounds like the stuff of 1950s horror movies, or something taken straight from the pages of Mary Shelley's Frankenstein. But scientists at Irvine, Calif.-based Tensor Biosciences haven't created a monster. Their Brain-on-a-Chip™ technology promises to speed up the development of drugs for treating a variety of psychiatric disorders, including anxiety, depression, and schizophrenia. The technology is based on an instrument developed by Panasonic in the mid-1990s for recording the electrical activity of neuronal networks in a slice of living brain tissue, says Miro Pastrnak, Tensor's director of business development. The tissue is placed on a glass chip containing a two-dimensional array of 64 microelectrodes that serve a dual function: The electrodes stimulate neural network activity in the brain tissue and record electrical activity after the tissue is infused with a drug. The electrical response of various locations on the tissue is recorded with a 100-microsecond time resolution to generate a spatial map of drug effects at different sites. Tensor has increased the system's throughput by developing a 16-chip system called DS-MED, which will be used in the near-future in collaborations with pharmaceutical companies. The Brain-on-a-Chip system provides researchers with an in vitro model of the brain that mimics the behavior of living tissue. It even permits coculturing of different brain tissues so that interactions between them can be studied. Pastrnak contrasts this with currently available cell-based assays, which are not able to model complex interactions and connections between different types of neuronal cells. "The brain is just more complex than other systems, and cell-based approaches are less likely to yield reliable results than in other areas," he explains. ©2003, The Scientist Inc.

Keyword: Miscellaneous
Link ID: 3354 - Posted: 06.24.2010

Various hypotheses focus on personality, age, parenting, and biology | By Mignon Fogarty For a teenager, sneaking a beer is one thing; shooting up heroin is quite another. Missing a parentally imposed curfew is almost expected; disappearing for days is heart-wrenching. There is risk, and then there is risk . Figuring out what differentiates experimenting teenagers from delinquents and lifelong reckless hearts is not easy; behaviors typically stem from complex social, environmental, and biological interactions. Even defining risky conduct can be difficult. "Often, individuals [engaging in risky behavior] don't think what they are doing is risky," explains Angela Bryan, an assistant professor of psychology, University of Colorado. "We all think we aren't going to get in an accident or we won't get [a] disease. That is very adaptive; if we were terrified every time we went out the door we'd never leave the house." Researchers who study risk-taking, particularly in the context of HIV infection, also struggle to find clear definitions. "You can't put shooting up with drugs and having sex with your husband in the same ballpark," says Mitch Katz, San Francisco's public health director. Many married people use no protection and society does not consider that risky, but if a partner injects drugs, a line gets crossed. "Early in the [AIDS] epidemic, one of the things we learned about women was that they were much more likely to become infected from their steady partners than their casual partners, because they were, from a medical standpoint, taking higher risks," he explains. But Katz does not necessarily put those people in the same category as high risk-takers, such as those who engage in backstreet racing or abuse alcohol. ©2003, The Scientist Inc.

Keyword: Genes & Behavior; Emotions
Link ID: 3353 - Posted: 06.24.2010

People who are over-aggressive or excessively anxious may be missing a gene, say scientists who conducted experiments on mice. The gene, called PET-1, was removed from specially-bred mice by scientists at Case Western Reserve University in the US. They found that the mice had heightened levels of both anxiety and aggression - when the mice were given a "territory", their response time to attack an intruder was significantly lower than a normal wild mouse, and they tended to launch an attack more often. Although mice are already fairly nervous creatures, when the genetically-modified animals were placed in a test chamber with a choice between an "unprotected" open space and "safe" enclosed space, they tended to stay in the latter for longer periods than normal mice. This, said the testers, was a clear sign that the mice were suffering more anxiety. (C) BBC

Keyword: Aggression; Genes & Behavior
Link ID: 3352 - Posted: 01.26.2003

By LAUREN SLATER A few weeks ago, a patient reported to the police that his psychiatrist confessed in the privacy of the consulting room that he planned to murder six people. And if that isn't bad enough, the Nassau County police also say that the doctor tried to enlist his patient's help, asking him to find chum (chopped bait) and a gun with a silencer, thereby making the paying customer an unwilling accomplice to something as grisly as the innermost portions of the id. The plot included killing a female patient who had become the psychiatrist's lover, according to the woman's lawyer. The doctor was arrested in a Home Depot parking lot; snap, he was handcuffed; snap snap, he was marched away and later charged with three counts of weapons possession by the Nassau County D.A.'s office, charges he denies. If the analysand has not yet found another therapist, he should, to help him deal with the trauma of his treatment. That therapy not only deals with trauma but also causes it is no new news, and yet the media are trotting out their predictable headlines -- ''LAWYER: L.I. SHRINK SAID SEX WAS RX''; ''LOVE-SCORNED SHRINK IN MASSACRE BID'' -- as though this is remarkable. It's not. Psychiatrists have been violating ''boundaries'' for as long as the profession has existed. Of course, not every case is as bizarre or extreme as the shrink with the wish to kill. Jung carried on a long affair with a patient; Bettelheim batted his children around; and on a more recent note, there are practitioners like Margaret Bean-Bayog, who shared her sexual fantasies with a patient, who later killed himself. Copyright 2003 The New York Times Company

Keyword: Depression; Schizophrenia
Link ID: 3351 - Posted: 01.26.2003

If they have to remember words, elderly persons in an early stage of dementia do not benefit from the relationship in meaning between these words. This was revealed in doctoral research by the neuropsychologist Pauline Spaan from the University of Amsterdam. It is now possible to develop memory tests which can predict dementia. One of the things revealed in Spaan's research was that elderly persons who were found to have dementia two years later, were scarcely better at remembering word pairs clearly linked in meaning (for example, pipe - cigar) than word pairs without such a link (for example nail - butter). However, elderly persons who did not have dementia two years later normally benefited from such a link in meaning when remembering word pairs. Spaan concluded that the memory problems of elderly people in an early stage of dementia could be attributed to a disrupted semantic processing. In addition it transpired that a test for the unconscious (implicit) recall of previously presented words significantly improved the prediction of dementia: elderly persons in the early stage of dementia did not benefit from the repeated presentation of words.

Keyword: Alzheimers; Learning & Memory
Link ID: 3350 - Posted: 01.26.2003

The days of gentlemen callers leaving their visiting cards are over, but if you are a male groundhog, visiting a few female burrows before the ladies come out in the spring may prove to smooth the way for later mating activities, according to a Penn State biologist. "Field observations indicate that males immerge later and emerge earlier than females," says Dr. Stam. M. Zervanos, associate professor of biology, Penn State Berks-Lehigh Valley College. Zervanos defines the date of immergence as the last day they monitored the groundhog above ground in the autumn and he defines the date of emergence as the first date they monitored the groundhog above ground in the spring. Groundhogs do not simply crawl into their dens and hibernate, but rather they experience a series of torpor and arousal events throughout winter. During arousal events they stay in their burrows, but in the spring, they emerge and move around above ground. They then return to the den for some more deep sleeping episodes before the final arousal for the season.

Keyword: Sexual Behavior; Biological Rhythms
Link ID: 3349 - Posted: 01.26.2003

Hardworking sodium/ potassium pump fundamentally similar to free-flowing ion channel Right now, in your body, tiny pumps in the fatty membranes surrounding all your cells are hard at work pushing select charged ions, such as sodium, potassium or calcium, through those membranes. Like a water pump in a high-rise apartment building overcoming the force of gravity to move water up to a tank on its roof, these ion pumps work against "electrochemical gradients" to transport ions from one side of the membrane to the other. Other tiny machines, called ion channels, also embedded within membranes, are like the apartment building's faucets: they harness the energy stored in this "uphill" process by allowing ions to rush back "downhill" across the cell membrane through the channels' open pores. Such movements of ions into and out of a cell form the basis for the transmission of signals in the brain and heart as well as other tissues of the body that allow you to breathe, move, think, digest food and pretty much function in all respects.

Keyword: Miscellaneous
Link ID: 3348 - Posted: 01.26.2003

By Jane E. Allen Alzheimer's research has yet to yield many useful therapies, even as the demand for treatments grows -- U.S. cases are expected to increase from 4 million to as many as 16 million by the middle of this century. A promising vaccine produced brain inflammation; medications that help patients function better during the early and moderate stages eventually lose ground to the incurable disease; and newer compounds to treat and prevent it remain years from reaching pharmacies. So it's not surprising that scores of people with Alzheimer's are signing up to have shunts implanted in their brains, an invasive approach that has become one of the few bright spots in Alzheimer's research. Dr. Gerald Silverberg, a Stanford neurosurgeon, reported that experimental shunts had slowed disease progression in a small group of patients. In that pilot study, published in an October 2002 issue of Neurology, he and his colleagues compared 12 patients with mild to moderate Alzheimer's who underwent shunt implantation with 11 Alzheimer's patients who received traditional care. After a year of monitoring, the surgical patients remained stable; comparison patients declined. Copyright © 2003, South Florida Sun-Sentinel

Keyword: Alzheimers
Link ID: 3347 - Posted: 06.24.2010

Researchers are investigating the burden stroke care can place on families and health services. Stroke is the third most common cause of death, but it receives far less attention than heart attacks - the biggest killer. Researchers warn the situation could worsen over the next 20 to 30 years, as the population ages. And, as statistics only record the 15 to 20% of strokes which are fatal, researchers believe the true number of people disabled by the condition is not reported. In the largest study of its kind to be carried out in the UK for 20 years, researchers will follow a population of 200,000 adults in Oxford. They will look at how many people suffer coronary vascular disease - heart disease - and cerebral vascular disease - strokes and transient ischaemic attacks (TIAs or "mini" strokes). (C) BBC

Keyword: Stroke
Link ID: 3346 - Posted: 01.25.2003

Techniques used by stargazers to get a clearer picture of the heavens are being harnessed by eye doctors. "Adaptive optics" is delivering a clear image of individual cells at the back of the eye. It could help diagnose potentially sight-threatening conditions before the patient has even noticed a problem. Experts believe that the techniques will become a part of NHS care within the next decade. When someone looks at a star in the night sky with the naked eye, it often appears to twinkle. This is distortion caused by temperature changes in the atmosphere - and can play havoc with the readings from powerful telescopes. Scientists found a way of using powerful computers to compensate for these and give a sharp image. (C) BBC

Keyword: Vision
Link ID: 3345 - Posted: 01.25.2003

A part of the brain called the medial temporal lobe (MTL) is critical for memory, but neuroscientists know little about which parts of the MTL do what. A new study, the first to tackle the question in humans, pinpoints one region of the MTL that lights up while new memories are being formed and another that blinks on when previously encoded memories are retrieved. It's difficult to study the MTL in living people because much of it is folded up like a jellyroll. That makes it hard to distinguish key components in functional magnetic resonance imaging (fMRI) scans. To overcome this obstacle, Susan Bookheimer and colleagues at the University of California, Los Angeles, employed mathematical tricks similar to those mapmakers use to turn globes into wall maps. Their flattened maps of the MTL show the borders between different regions. Copyright © 2003 by the American Association for the Advancement of Science.

Keyword: Learning & Memory
Link ID: 3344 - Posted: 06.24.2010

A child who is afraid of the dark may not be seeking attention - as many parents would suspect - but rather suffering from night blindness. Researchers say the condition is rare, and the diagnosis can often be missed. Most people's eyes adjust to the dark after a short period of time. But some children, who have no obvious visual problems and who can see normally in well-lit conditions, can have difficulty seeing in the dark even after this period of adaptation. Writing in the British Medical Journal, researchers from the Gartnavel General Hospital, Glasgow, detail two cases of a form of the condition congenital stationary night blindness. A three-year-old girl was brought to doctors by her parents who said she persistently complained about not being able to see in the dark. (C) BBC

Keyword: Vision
Link ID: 3343 - Posted: 01.24.2003

A dye used for more than a century to stain autopsied brain tissue can prevent the devastating effects of Huntington's disease in mice, new research shows. The dye, called Congo red, breaks apart hallmark protein clumps in the brain, adding to evidence that these globs are to blame for symptoms of the disease. In Huntington's disease, an inherited and fatal neurological disorder, proteins called huntingtin mass together in the brain and kill neurons. However, scientists have long debated whether the proteins themselves or primarily their aggregates cause the neurological decline characteristic of Huntington's. No existing treatments can slow the disease's progression, and most victims die by midlife. Cell biologist Junying Yuan and her colleagues at Harvard Medical School in Boston were curious whether Congo red could break down aggregates of huntingtin. Other researchers had found hints in cultured cells that the commonly used dye could break apart proteins involved in related ailments such as Alzheimer's disease and prion diseases, and preliminary evidence suggested they might work against Huntington's. Yuan's team exposed human brain cells to Congo red between 6 and 48 hours after they began producing huntingtin. Adding the dye earlier caused a 60% decrease in cell death; adding it later reversed aggregation and prevented some damaging effects, like a loss of energy-producing ATP. Closer examination showed that Congo red forced protein aggregates to break apart. Copyright © 2003 by the American Association for the Advancement of Science.

Keyword: Huntingtons
Link ID: 3342 - Posted: 06.24.2010

The results announced in the International Journal of Psychophysiology this month show a link between neurofeedback training and improved memory in a 40 person trial. Dr David Vernon, from Imperial College London at the Charing Cross hospital says: "Previous research has indicated that neurofeedback can be used to help treat a number of conditions including Attention Deficit Hyperactivity Disorder, epilepsy and alcoholism by training particular aspects of brain activity, but this is the first time we have shown a link between the use of neurofeedback, and improvements in memory." Neurofeedback is a learning procedure that has been involved in treatments enabling participants to normalize behaviour, stabilize mood and improve their cognitive performance. It works by allowing people to watch their brain activity, and through this, find a way to correct or improve it.

Keyword: Learning & Memory
Link ID: 3341 - Posted: 01.24.2003

Advocates of genetic determinism square off against two prominent Stanford University scientists in a lively and surprisingly acerbic debate over ''nature vs. nurture'' in the February issue of the journal Current Anthropology. The often contentious dialogue, which fills 20 pages of the journal, revolves around a controversial essay titled ''Genes and Cultures: What Creates Our Behavioral Phenome?'' by Stanford biologists Paul R. Ehrlich and Marcus W. Feldman. ''A central theme of the flood of literature in recent years in 'evolutionary psychology' and 'behavioral genetics' is that much or even most human behavior has been programmed into the human genome by natural selection,'' Ehrlich and Feldman wrote. ''We show that this conclusion is without basis.''

Keyword: Evolution; Genes & Behavior
Link ID: 3340 - Posted: 01.24.2003