By Richard Maddock "My heart starts to race, I can't breathe, I get all sweaty, and I feel very scared - like I am about to die." This is how one of my patients recently described her panic attacks. Her diagnosis is panic disorder. The cause of this condition is still not understood, but we have long known that the vulnerability to panic disorder is strongly genetic. Now, a recent study from the laboratory of John Wemmie at the University of Iowa may have revealed an important new clue to the underlying cause of recurring panic attacks: It may, in effect, be a problem of pH -- of acidity at key junctures in the brain. The amygdala, an almond-shaped structure deep in the brain, has a critical role in the circuits that control the experience of fear, both instinctive fear (like being afraid of snakes or large carnivores) and fear that is learned from life experiences. The Iowa study shows that a very basic metabolic factor, pH -- acidity -- also has an essential role in fear. In general, the pH of our brain is carefully regulated. A large increase or decrease in brain acidity can seriously disrupt brain functioning. This new study indicates that pH can sometimes rise and fall in synapses, the points of communication between individual neurons in the brain. Some synapses include specialized proteins that "sense" acidity. These proteins (called "'acid-sensing ion channels", or ASICs) stimulate neurons when increased acid is detected. © 2010 Scientific American,

Keyword: Emotions; Stress
Link ID: 14093 - Posted: 06.24.2010

By Susan Gaidos The glow of pregnancy is no shield against depression. Millions of expectant mothers rely on antidepressant medication for help. But treating mom with drugs at this time in her life may have long-term consequences for baby. Around 10 percent of women suffer bouts of despair during the hormonal chaos of pregnancy or in the months after delivery. Some women are already being treated with antidepressants such as Prozac and Zoloft, while others get new prescriptions. For many adults these drugs, known collectively as selective serotonin reuptake inhibitors or SSRIs, work as advertised: lifting mood by temporarily boosting the availability of the brain chemical serotonin. But SSRIs may have a different, more long-lasting effect on a developing baby’s brain. Over the past few years, a handful of studies have found that mice and rats exposed to antidepressants shortly before birth or just afterward grow up anxious and depressed. Other animal studies link early exposure to SSRIs to improved decision-making and spatial-learning abilities. Though many of the documented reactions fall within the normal range of behavior, the drugs can influence how an animal experiences and relates to its surroundings, says Judith Homberg of Radboud University in Nijmegen, the Netherlands. No one knows for sure if people experience the same risks or benefits over the long haul, but a new study shows that children exposed to antidepressants in the womb are more likely to appear sad or withdrawn at age 3 than those whose moms didn’t take the drugs. © Society for Science & the Public 2000 - 2010

Keyword: Depression; Development of the Brain
Link ID: 14092 - Posted: 06.24.2010

By Bruce Bower There’s nothing fair about getting bullied at school. To add insult to injury, a new study finds that bullied kids who happen to have inherited one form of a stress-related gene develop the most emotional problems. Symptoms of anxiety, depression and social withdrawal appeared most often in regularly bullied kids who possessed two copies of a short version of the 5-HTT gene, says a team led by psychologist Karen Sugden of Duke University in Durham, N.C. One-third of bullied children who had two shorter copies of the gene displayed emotional problems severe enough to merit mental health treatment, the researchers say. That figure fell to 29 percent for regularly bullied kids carrying one short copy of the gene and 15 percent for those with two long copies. By tracking pairs of twins, Sugden and her colleagues ruled out the possibility that pre-existing emotional problems led genetically vulnerable children to be victimized by bullies. In cases where each twin carried two short copies of the 5-HTT gene but only one got repeatedly bullied, emotional difficulties were observed only in the bullied twin, the researchers report in a paper scheduled to appear in the Journal of the American Academy of Child & Adolescent Psychiatry. The experiment can’t directly pin the kids’ emotional problems on the gene-bullying combo, “but it is about as close as it is possible to get, given that it’s not ethical to bully a child deliberately for research purposes,” says Duke psychologist and study coauthor Terrie Moffitt. © Society for Science & the Public 2000 - 2010

Keyword: Depression; Genes & Behavior
Link ID: 14091 - Posted: 06.24.2010

by Jeff Wise Copyright © 2009 by the author In the throes of intense fear, we suddenly find ourselves operating in a different and unexpected way. The psychological tools that we normally use to navigate the world—reasoning and planning before we act—get progressively shut down. In the grip of the brain’s subconscious fear centers, we behave in ways that to our rational mind seem nonsensical or worse. We might respond automatically, with preprogrammed motor routines, or simply melt down. We lose control. In this unfamiliar realm, it can seem like we’re in the grip of utter chaos. But although the preconscious fear centers of the brain are not capable of deliberation and reason, they do have their own logic, a simplified suite of responses keyed to the nature of the threat at hand. There is a structure to panic. When the danger is far away, or at least not immediately imminent, the instinct is to freeze. When danger is approaching, the impulse is to run away. When escape is impossible, the response is to fight back. And when struggling is futile, the animal will become immobilized in the grip of fright. Although it doesn’t slide quite as smoothly off the tongue, a more accurate description than “fight or flight” would be “fight, freeze, flight, or fright”—or, for short, “the four fs.” On a winter morning a few years back, a young woman named Sue Yellowtail went through them all in about 10 minutes.

Keyword: Emotions; Stress
Link ID: 14090 - Posted: 06.24.2010

By Nathan Seppa An intensive course of behavioral therapy can limit the verbal and physical tics that plague some children with Tourette disorder, a new study finds. This form of therapy, in which a child learns simple ways to derail tics, led to improvement in more than half of children treated, scientists report in the May 19 Journal of the American Medical Association. “I think this is groundbreaking,” says clinical psychologist Martin Franklin of the University of Pennsylvania in Philadelphia, who didn’t participate in the trial. “Clinically, we now have pretty powerful evidence of the efficacy of a behavioral treatment in this disorder.” Tourette disorder is characterized by short, rapid physical or vocal tics that can take the form of jerking motions, blinking, grimacing, blurting out words or throat clearing. These tics are brought on by urges. And much as a cigarette satisfies a smoker’s need for nicotine, the tics seem to resolve these urges, but at a cost. People with Tourette disorder, which starts in childhood and affects about six in 1,000, can face isolation and social stigmatization. “The urge-tic-relief cycle becomes automatic over time” in Tourette disorder, says study coauthor John Piacentini, a clinical psychologist at the University of California, Los Angeles. “We want to slow it down and make it less automatic.” © Society for Science & the Public 2000 - 2010

Keyword: Tourettes
Link ID: 14089 - Posted: 06.24.2010

By Katherine Harmon Strange tales of lactating men or male pregnancy pains crop up in the news from time to time, despite the fact that men cannot get pregnant. Does that mean men are also susceptible to bouts with prenatal and postpartum depression? Previous research has found rates of depression in new dads that range from 1 percent to 25 percent, but a new meta-analysis, published May 19 in JAMA, Journal of the American Medical Association, assessed 43 studies of a total of more than 28,000 fathers and found that an average of 10.4 percent suffered from depression sometime between the first trimester of their partner's pregnancy and the child's first birthday. Rates of paternal depression were highest three to six months after birth (25.6 percent) and in the U.S. (14.1 percent versus the international rate of 8.2 percent). All of these numbers are considerably higher than the annual rate for adult male depression, which is 4.8 percent (but lower than the rate for maternal prenatal and postpartum depression, which is estimated to be 23.8 percent). "This suggests that paternal prenatal and postpartum depression represents a significant public health concern," concluded the authors of the new paper. Many moms get what is known as the baby blues, a passing sadness in the first few days after the birth of their child. But postpartum depression in both mothers and fathers is a condition that lasts longer, and "it may be very problematic for families and child outcomes," says James Paulson of the Department of Pediatrics at Eastern Virginia Medical School, the lead author of the meta-analysis. © 2010 Scientific American,

Keyword: Depression
Link ID: 14088 - Posted: 06.24.2010

Alison Abbott. Anne Churchland had little time for rats. In the course of 13 years' work on decision-making in monkeys, she had never questioned that primate studies were the only way to understand the neurobiology of human cognition. Her work in the lab of Michael Shadlen at the University of Washington, Seattle, had monkeys watch moving dots flitting about on a screen until the animals indicated, with a flick of their eyes, the direction in which most of the dots were going. She recorded from single brain neurons as the monkeys slowly made sense of this 'fuzzy' information — the sort of sophisticated experiment that she did not think was possible in rodents. "I didn't think rats would have the right sorts of brains to contemplate accumulating evidence," says Churchland. And with poor eyesight, and heads that bob around, "I didn't imagine they would be able to convey to us any decision they might be silently making". All that changed a year ago, when Churchland visited Cold Spring Harbor Laboratory in New York. Working with scientists there, she saw that rats could also learn to gather 'fuzzy' sensory information — in this case to decide whether the frequency of a rapid sequence of tones was mostly high or low. And they could convey their decision with a poke of the nose. Churchland was not alone in her earlier scepticism. Neurophysiological research into higher cognitive functions such as decision-making, attention, working memory — even risk-taking — have traditionally been carried out on non-human primates. That seemed an obvious choice, given the closeness of their brain anatomy to that of humans, the sophistication and breadth of their behaviour and their ability to reliably report to experimenters much of what is going on in their minds through eye, hand or other movements. But primate work comes with major downsides: the animals are so expensive, and their use so highly regulated, that a research paper typically relies on data from just a couple of precious animals, which have been used for multiple experiments over their lifetime. This raises concerns that observations could be unique to those animals, rather than a general property of the primate brain. © 2010 Nature Publishing Group

Keyword: Attention; Learning & Memory
Link ID: 14087 - Posted: 06.24.2010

By Diane Mapes Being a “supertaster” may sound like a foodie’s dream come true, but in reality, it’s no picnic. Coffee and alcohol are unpalatable – along with tomatoes, Parmesan cheese, strawberries, condiments and most sweets. “I can’t stand cake,” says Michelle Triplett, a 31-year-old stay-at-home mom and supertaster from Olympia, Wash., who spoke, coincidentally, on her birthday. “It’s too sweet for me. And when I drink beer, I gag. It’s like drinking urine.” Supertasters detect components – like salt or bitterness -- in food that others can’t, says Dr. Alan Hirsch, founder and neurological director of the Smell & Taste Treatment and Research Foundation in Chicago. “[Supertasters] have densities of taste buds that are 10 to 100 times greater than the normal population,” he says. “As a result, supertasters are much more sensitive to spicy foods and they can taste … very mild flavors.” Triplett, whose favorite meals are turkey sandwiches and macaroni and cheese, says the blander the better, since most everything else is, as They Might Be Giants put it in their song “John Lee Supertaster,” simply “too much.” The condition is genetic, tends to affect women more than men and affects 25 percent of the U.S. population; non-tasters (people with a reduced ability to taste) make up another 25 percent with the rest of the population described as medium or normal tasters. © 2010 Microsoft

Keyword: Chemical Senses (Smell & Taste)
Link ID: 14086 - Posted: 06.24.2010

By Katherine Harmon Despite weighty concerns, such as aging, planning for retirement or caring for older friends and family, people in the U.S. seem to get happier with age. A new study reports that these changes are consistent regardless of whether individuals were employed, had young children at home or lived with a partner. General wellbeing (characterized by how people currently felt about their life) fell sharply through the age of 25 and tapered more gradually overall until the ages of 50 to 53. And by the early 70s, that wellbeing was back up to late-teen levels. "As people age, they are less troubled by stress and anger," the researchers noted in their study, which was led by Arthur Stone, of the Department of Psychiatry and Behavioral Science at Stony Brook University and published online May 17 in the Proceedings of the National Academy of Sciences. "And although worry persists, without increasing, until middle age, " they continued, "it too fades after the age of 50." The data come from a 2008 phone survey performed by the Gallup Organization of 340,847 randomly selected adults aged 18 to 85. The respondents represented a fairly average slice of the U.S. population, with about 29 percent holding a college degree and a median monthly average household income between $3,000 and $3,999. During the call, participants were asked to rate how they currently felt their life stood on a scale of 0 ("the worst possible life for you") to 10 ("the best possible life for you"). They were then asked if they had felt different affective states (happiness, enjoyment, stress, sadness, anger and worry) "a lot of the day yesterday." Keeping questions to relatively current periods in time by asking about yesterday as opposed to the previous week, month or year helped the researchers avoid some of the retrospective bias that might have played a role in similar past studies. © 2010 Scientific American,

Keyword: Emotions; Development of the Brain
Link ID: 14085 - Posted: 06.24.2010

by Sandrine Ceurstemont A simple animation has been found to offer our brains many possible interpretations. Jan Kremláček from Charles University in Hradec Králové, Czech Republic, discovered six different ways of perceiving a moving sine graph drawn with dots. The curves often seem to undulate like two ribbons, but the animation can also seem to have depth, with one curve seeming to be further back than the other. The dotted arcs can also look like a spindle shape that revolves and snakes along. If you keep staring, the curves can seem to revolve vertically around a static rod, first in one direction, then the other. The animation can also look like a series of bouncing dots, but this is very hard to perceive without overlaying vertical bars on top of it. "Our brain is able to reconstruct different learned interpretations, but only one can be perceived at a time," says Kremláček. He came across the illusion by chance while preparing graphs for a lecture in signal processing. © Copyright Reed Business Information Ltd.

Keyword: Vision
Link ID: 14084 - Posted: 06.24.2010

by Carl Zimmer Your nose is a paradox. In some ways the human sense of smell is astonishingly precise. For example, natural gas companies add a smelly molecule called n-butyl mercaptan to natural gas, which is odorless by itself, so that people can sniff gas leaks. All it takes is one n-butyl mercaptan molecule for every 10 billion molecules of methane to do the trick. To put this precision in perspective, imagine you are standing in front of two Olympic-size swimming pools. One of them contains a grand total of three drops of n-butyl mercaptan, and the other has none. Your nose could tell the difference. But don’t get too smug, because in other ways your sense of smell is practically useless. To judge for yourself, find someone to help you run a simple experiment. Close your eyes while your partner raids your refrigerator and then holds different foods under your nose. Try to name each scent. If you’re like most people, you’ll bomb. In a number of studies, scientists have found that people tested on items in their own kitchens and garages give the wrong answer at least half the time. And as bad as we normally are at identifying smells, we can easily be fooled into doing worse. If orange food coloring is added to cherry-flavored soda, for example, people are more likely to say that it smells like oranges. Noam Sobel of the Weizmann Institute of Science in Israel and his colleagues have been puzzling over this paradox for the past several years. What has been missing in the science of smell, they argue, is a meaningful way to measure it—an olfactory yardstick. Now they have built one.

Keyword: Chemical Senses (Smell & Taste)
Link ID: 14083 - Posted: 06.24.2010

By Nathan Seppa Elderly people who care for a spouse who has dementia are at increased risk of developing dementia themselves, a study finds. The stress of attending to a mentally incapacitated spouse may somehow contribute to the added risk, scientists report in the May Journal of the American Geriatrics Society. Previous studies have shown that chronic stress leads to increased levels of the hormone cortisol in the body, which can suppress immunity, says study coauthor Peter Rabins, a psychiatrist at Johns Hopkins School of Medicine in Baltimore who teamed with researchers at Utah State University in Logan to do this study. “It’s long been thought that this might have adverse outcomes psychologically and physiologically.” Taking care of a spouse with dementia takes a toll in other ways as well, Rabins says. “Caregivers often complain that they lose their friends,” he says, because they don’t have time to socialize. But the biological mechanisms that might link these challenges to heightened dementia risk remain unclear. In the new study, the researchers assessed the mental status of 1,221 Utah couples who had agreed to be part of a community-wide health study that started in 1995. The men averaged age 76 and the women 73 at that point, and 95 percent had been married for more than 20 years. Researchers tracked these couples’ mental status with up to four exams over the next decade with a median follow-up of 3.3 years. No participants in this analysis had dementia at the start. © Society for Science & the Public 2000 - 2010

Keyword: Alzheimers; Stress
Link ID: 14082 - Posted: 06.24.2010

Newborn infants are capable of a simple form of learning while they’re asleep, according to a study by researchers funded by the National Institutes of Health. The finding may one day lead to a test that can identify infants at risk for developmental disorders that do not become apparent until later in childhood. The study was confined to newborns, so the researchers do not know whether older children or adults are capable of learning during sleep. Funding for the study was provided by the NIH’s Eunice Kennedy Shriver National Institute of Child Health and Human Development. Additional funding was provided by the National Institute of Mental Health. Conducted by William Fifer, Ph.D. and his colleagues at Columbia University in New York, the study was published today online in the Proceedings of the National Academy of Sciences. Researchers used an electroencephalogram, a machine that records the brain’s electrical activity and converts it into patterns, to record the brain activity of each sleeping infant. A video camera recorded each infant’s facial expressions. The researchers played a tone, while a machine blew a faint puff of air at each sleeping infant’s eyelids. In response to the air puff, the infants reflexively squeezed their closed lids tighter. The researchers repeated this nine times, each time pairing the air puff with the tone. For the tenth time in the sequence, however, the researchers played the tone without the air puff. This sequence was repeated over and over again. After roughly 20 minutes, most of the infants (24 out of 26) would scrunch their faces in response to the tone that was not accompanied by the air puff. Moreover, the electroencephalogram detected changes in brain wave activity that occurred simultaneously with the tone, which the researchers interpret as further evidence that the infants had learned to associate the tone with the air puff.

Keyword: Sleep; Learning & Memory
Link ID: 14081 - Posted: 06.24.2010

By Emily Sohn Teenagers do crazy things, and the chemistry of their brains might explain why. In a new study, scientists found that the adolescent brain is extra sensitive to the rewarding signals it gets when something better than expected happens. The discovery might help explain why teens take risks that don't seem worth it to adults -- from driving too fast to experimenting with drugs. "Teenagers seek out these sorts of rewarding experiences, and this provides a little explanation for that," said Russell Poldrack, a cognitive neuroscientist at the University of Texas, Austin. "In the long run, it may help us understand how addictions start and develop." To zero in on the neuroscience behind risk-taking behavior in adolescents, Poldrack and colleagues focused on a concept called prediction error, which describes the difference between what a person expects to happen and what actually happens. If you anticipate a rich sip of full-bodied espresso, for example, but you end up gulping weak, watery, and burnt coffee, that's a negative prediction error. If you expect nothing from a friend for your birthday but he gives you $20, that's a positive error -- far better than expected. To test the brain's reaction to positive prediction errors at different stages of life, the scientists enlisted 45 people, ranging in age from 8 to 30. Each participant was shown a series of abstract kaleidoscopic images and challenged to categorize the figures as logos belonging to one of two fictional colleges. © 2010 Discovery Communications, LLC.

Keyword: Development of the Brain; Drug Abuse
Link ID: 14080 - Posted: 06.24.2010

By JoNel Aleccia Exposure to pesticides used on common kid-friendly foods — including frozen blueberries, fresh strawberries and celery — appears to boost the chances that children will be diagnosed with attention deficit hyperactivity disorder, or ADHD, new research shows. Youngsters with high levels of pesticide residue in their urine, particularly from widely used types of insecticide such as malathion, were more likely to have ADHD, the behavior disorder that often disrupts school and social life, scientists in the United States and Canada found. Kids with higher-than-average levels of one pesticide marker were nearly twice as likely to be diagnosed with ADHD as children who showed no traces of the poison. “I think it's fairly significant. A doubling is a strong effect,” said Maryse F. Bouchard, a researcher at the University of Montreal in Quebec and lead author of the study published Monday in the journal Pediatrics. The take-home message for parents, according to Bouchard: “I would say buy organic as much as possible,” she said. “I would also recommend washing fruits and vegetables as much as possible.” Diet is a major source of pesticide exposure in children, according to the National Academy of Sciences, and much of that exposure comes from favorite fruits and vegetables. In 2008, detectable concentrations of malathion were found in 28 percent of frozen blueberry samples, 25 percent of fresh strawberry samples and 19 percent of celery samples, a government report found. © 2010 msnbc.com

Keyword: ADHD; Neurotoxins
Link ID: 14079 - Posted: 06.24.2010

By Judy Foreman The symptoms of restless legs syndrome sound so bizarre — creepy-crawly feelings and an uncontrollable urge to move the legs, especially at bedtime — that until recently, many people who experienced it simply weren’t believed when they described it to others. Betsy Dunn, an 85-year-old Cambridge businesswoman who has had restless legs for nearly 30 years, remembers a doctor saying she must be depressed. “I walked out and never went back,’’ she says. “All I needed him to say was, ‘I don’t know what this is, but together we will find out.’ ’’ In severe cases, like that of Donald Loveland, 75, a retired Duke University computer scientist now living in Dennis, the urge to move the legs overwhelms everything else, including pain. Right after back surgery, he recalls, “it was actually painful to be up but I had to get up anyway.’’ Ron Blum, 38, a Jamaica Plain e-mail marketer who first noticed his symptoms as a 7-year-old, recalls that the minute he lay down and tried to sleep, “my left leg felt like it had to go for a walk.’’ Though he never told his parents, he’d get up and walk for hours in circles. It wasn’t until years later that a friend heard about RLS. “He called me up and said, ‘Ron, I know what you have. It has a name.’ ’’ It also has growing recognition. RLS may affect some 12 million Americans, according to the National Institute of Neurological Disorders and Stroke, as reported on the National Institutes of Health website (www.ninds.nih.gov/disorders). The NIH supports research into the condition at major medical institutions across the country, as well as within its own labs. © 2010 NY Times Co.

Keyword: Movement Disorders
Link ID: 14078 - Posted: 06.24.2010

By Laura Sanders A quick flash of light has confirmed the key assumption justifying the use of functional magnetic resonance imaging to reveal the inner workings of living brains. In a study appearing online May 16 in Nature, researchers used light to activate nerve cells and then saw the telltale fMRI signal, demonstrating that nerve cell activity is indeed responsible for the colorful splotches appearing on fMRI images. The new technique, called optogenetic fMRI, may lead to a much deeper understanding of how information travels through the brain. These results “put the fMRI field on firm footing,” by showing unambiguously that neuron activity can cause the fMRI signal, says study coauthor Karl Deisseroth of Stanford University. One of the most common versions of fMRI doesn’t directly measure the activity of nerve cells, or neurons, in the brain (SN: 12/19/09, p. 16). Instead, the typical method, called BOLD (for blood oxygen level-dependent), tallies slight changes in oxygen levels in the blood that surrounds neurons. Presumably, as neurons become active, they need more energy and consume more oxygen. These tiny fluctuations in oxygen serve as a proxy for brain activity. But direct evidence for this causal relationship has been lacking. Deisseroth and colleagues used a technique pioneered in their lab called optogenetics, in which light-responsive molecules are used to control particular cells (SN: 1/30/10, p. 18). To directly test the relationship between neuron activity and BOLD signal, the researchers inserted a molecule that responds to a pulse of blue light into neurons in the motor cortex of rats. Under normal conditions, these neurons activate and send the “go” signal when the rat wants to move a leg. With the addition of the light-responsive molecule, these neurons also fire when a pulse of blue light strikes. Armed with the ability to activate select groups of neurons at will, Deisseroth and colleagues could play with the switch and see when BOLD signals were made. © Society for Science & the Public 2000 - 2010

Keyword: Brain imaging
Link ID: 14077 - Posted: 06.24.2010

By Cristen Conger A debate is brewing in the bat research community over one of the winged mammal’s senses. No, it has nothing to do with vision. Despite the tiny eyes and nocturnal lifestyle, none of the roughly 1,100 bat species is blind. “All bats can see and all bats are sensitive to changing light levels because this is the main cue that they use to sense when it is (night time) and time to become active,” said Paul Faure, of McMaster University’s Bat Lab. Instead, researchers can’t agree on a certain aspect of the mammal’s sonar sight, called echolocation. To track down prey, avoid predators and find their way home in the dark, most bats depend on echolocation. They broadcast high-pitched sonar signals and listen for the echoes of sound waves bouncing off objects they’re looking for or obstacles in their path. Bats’ brains then process the auditory information within those echoes as visual maps. Scientists know a lot about the finer points of how echolocation works, but they differ on whether that sense evolved before or after bat’s ability to fly. “Some question whether echolocation 60 million years ago would’ve been too sophisticated,” said Brock Fenton, of the University of Western Ontario. The scientists who discovered Onychonycteris finneyi, the oldest known bat fossil (above), concluded that the prehistoric species could fly but that the sonar sense didn't evolve until later. © 2010 Discovery Channel

Keyword: Hearing; Evolution
Link ID: 14076 - Posted: 06.24.2010

By Jeremy Laurence, A blood test to assess the risk of brain damage in vulnerable newborn babies could save lives and prevent disability, scientists say. The test, carried out on blood taken from the umbilical cord immediately after birth, measures its acidity (the pH level). Blood with a low pH (more acid) indicates a lack of oxygen at birth, which is the commonest cause of brain damage, cerebral palsy and death. Current guidelines suggest that measuring the pH level of umbilical cord blood is worthless as a predictor of how the baby will fare, because the association is inconsistent. But doctors based in Birmingham reviewed 51 studies involving almost 500,000 babies and found a low pH in the cord blood was strongly linked with serious outcomes. Based on their findings, published in the British Medical Journal, they call for increased surveillance of babies born with low cord blood pH and for further research to explore the cost effectivenees of doing the test on all babies. In an accompanying editorial, James Neilson, professor of obstetrics and gynaecology at the University of Liverpool, said: "We should aim to reduce the number of babies born with a low cord pH, without increasing unnecessary obstetric intervention." Andy Shennan, professor of obstetrics at St Thomas' Hospital in London welcomed the study into the relationship between low pH and future health. "Lack of oxygen to the baby during labour will result in a low pH in the umbilical cord," he said. "If it is prolonged, irreversible neurological damage can occur, although this is rare." ©independent.co.uk

Keyword: Development of the Brain
Link ID: 14075 - Posted: 06.24.2010

by Leigh Krietsch Boerner Even if a mouse has never seen a cat before, he’ll turn tail when one is nearby. Researchers suspected that the rodents somehow sniff out their would-be assassins, but exactly what they smelled was unclear. Now scientists have isolated the compound, one of a class of urinary proteins that are secreted by cats, snakes, and a variety of other predators. Mice have two different ways to pick up scents: their nose and a specialized organ inside their nose called the vomeronasal organ (VNO), which helps them detect other mouse pheromones. Suspecting that VNO might help the rodents sniff out predators as well, neurobiologist Lisa Stowers of The Scripps Research Institute in San Diego, California, dropped cotton balls laced with either cat saliva, rat urine, or snake skin essence into the cages of both normal and mutant mice with inactive VNOs. The normal mice cowered in the corner, as if a predator were present. Meanwhile, the mutants weren’t afraid at all, even when an anesthetized rat was placed in their cage. “Some of the subjects were so relaxed that they actually curled up and went to sleep next to the rat,” Stowers says. In addition, using dyes that light up when neurons are activated, the team saw neurons associated with VNOs turn on in response to the scents. These mice were inbred in labs for hundreds of generations, none of them having ever seen a predator, Stowers notes. “This isn’t the mouse learning to recognize these cues,” she says, “he’s born with the ability to detect them.” © 2010 American Association for the Advancement of Science.

Keyword: Chemical Senses (Smell & Taste); Emotions
Link ID: 14074 - Posted: 06.24.2010