Biological Psychology Links

by Michael Marshall Humans, apes and monkeys have their mothers to thank for their large brains. It takes a lot of energy to make and run a brain, so large ones should only have developed in animals with fast metabolisms. But according to Vera Weisbecker of the University of Cambridge and Anjali Goswami of University College London, that's only part of the story. The pair looked at the brains of 197 marsupials and 457 placental mammals, and could find a link between metabolic rate and brain size only in placental mammals. This suggests that parenting strategies play a key role. "Placental babies are connected to their mothers via the placenta for a long time," says Weisbecker. "So if she has a high metabolic rate, the baby is more likely to benefit." By contrast, marsupial babies are born while they are still very small, then spend a long time feeding off their mothers' milk – a slower way to grow a large brain. Placentas offer a continuous supply of rich nutrients. However, the pair found no difference in the average brain sizes of marsupials and placental mammals – as long as they excluded primates. These, it seem, got their disproportionately large brains from a double maternal boost. They are supplied with large amounts of energy by their mothers during gestation, and then receive additional months or even years of care after birth. Journal reference: Proceedings of the National Academy of Sciences, DOI: 10.1073/pnas.0906486107 © Copyright Reed Business Information Ltd.

By JANE E. BRODY You may think you know why Americans continue to get fatter and develop obesity-related diseases. But the explanation may start long before people have an opportunity to eat too much of the wrong foods and exercise too little. Increasing evidence indicates that the trouble often starts in the womb, when women gain more weight than is needed to produce a healthy, full-size baby. Excessive weight gain in pregnancy, recent findings show, can result in bigger-than-average babies who are prenatally programmed to become overweight children — who, in turn, are more likely to develop diabetes, heart disease and cancer later in life. The Institute of Medicine, the health arm of the National Academy of Sciences, reported last year that more than a third of normal-weight women and more than half of overweight and obese women gain more weight than is recommended during pregnancy. Over all, “fewer than 40 percent of pregnant women gain only the recommended amount of weight during their pregnancy,” Dr. Sylvia R. Karasu and Dr. T. Byram Karasu report in their new book “The Gravity of Weight.” While genes play a role in weight issues for some people, recent studies indicate that genetics is not the main reason babies are born too fat. Rather, the new evidence suggests that in addition to gaining significantly more weight than is recommended during pregnancy, more women now start out fatter before they become pregnant. Copyright 2010 The New York Times Company

By Bruce Bower Toddlers get a kick out of giving adults a hard time. True to form, these wobbly-legged knowledge-sponges learn virtually nothing from best-selling DVDs that their parents believe will boost vocabulary and trigger academic superstardom. Young children who viewed a popular DVD regularly for one month, either with or without their parents, showed no greater understanding of words from the program than kids who never saw it, according to a study slated to appear in Psychological Science. “The degree to which babies actually learn from baby videos is negligible,” says psychologist and study director Judy DeLoache of the University of Virginia in Charlottesville. Still, adults who initially liked the DVD thought that their children learned many words by watching it. DeLoache suspects that some parents mistakenly assume that educational DVDs such as Baby Einstein prompt the spike in word learning that naturally occurs between 12 and 24 months of age (SN: 4/25/98, p. 268). Annual sales of Baby Einstein products now reach about $200 million in the United States. Other companies sell competing educational DVDs in what is now an international business. DeLoache calls the educational DVD she used in her new study “one of the best available” but wouldn’t identify the brand. © Society for Science & the Public 2000 - 2010

By DUFF WILSON OPELOUSAS, La. — At 18 months, Kyle Warren started taking a daily antipsychotic drug on the orders of a pediatrician trying to quell the boy’s severe temper tantrums. Thus began a troubled toddler’s journey from one doctor to another, from one diagnosis to another, involving even more drugs. Autism, bipolar disorder, hyperactivity, insomnia, oppositional defiant disorder. The boy’s daily pill regimen multiplied: the antipsychotic Risperdal, the antidepressant Prozac, two sleeping medicines and one for attention-deficit disorder. All by the time he was 3. He was sedated, drooling and overweight from the side effects of the antipsychotic medicine. Although his mother, Brandy Warren, had been at her “wit’s end” when she resorted to the drug treatment, she began to worry about Kyle’s altered personality. “All I had was a medicated little boy,” Ms. Warren said. “I didn’t have my son. It’s like, you’d look into his eyes and you would just see just blankness.” Today, 6-year-old Kyle is in his fourth week of first grade, scoring high marks on his first tests. He is rambunctious and much thinner. Weaned off the drugs through a program affiliated with Tulane University that is aimed at helping low-income families whose children have mental health problems, Kyle now laughs easily and teases his family. Ms. Warren and Kyle’s new doctors point to his remarkable progress — and a more common diagnosis for children of attention-deficit hyperactivity disorder — as proof that he should have never been prescribed such powerful drugs in the first place. Copyright 2010 The New York Times Company

By TARA PARKER-POPE For kids around the country it’s back-to-school time. But for many of them, it’s also the return of headache season. Doctors say frequent headaches and migraines are among the most common childhood health complaints, yet the problem gets surprisingly little attention from the medical community. Many pediatricians and parents view migraines as an adult condition. And because many children complain of headaches more often during the school year than the summer, parents often think a child is exaggerating symptoms to get out of schoolwork. Often the real issue, say doctors, is that changes in a child’s sleep schedule, including getting up early for school and staying up late to study, as well as skipping breakfast, not drinking enough water and weather changes can all trigger migraines when the school year starts. “In many areas people just don’t think kids can get migraines,” says Dr. Andrew Hershey, professor of pediatrics and neurology and director of the headache center at Cincinnati Children’s Hospital Medical Center. “But kids shouldn’t be missing activities and having trouble at school because they’re having headaches. If it happens, it shouldn’t be ignored.” Migraine is an inherited neurological condition characterized by severe, often disabling headache pain. During a migraine attack, a number of changes occur throughout the brain causing dilation of blood vessels; severe pain; increased sensitivity to lights, sounds and smells; nausea and vomiting; and other symptoms. It’s estimated that about 10 percent of young children and up to 28 percent of older teenagers suffer from migraines. (Hormonal changes during puberty can also be a trigger.) Copyright 2010 The New York Times Company

By Karen Weintraub It was the week the medication didn’t work that convinced Melissa Zolecki. She thinks her son Matthew got a bottle of inactive dummy pills that week by accident. And the change in his behavior was striking. The MIND Institute at the University of California Davis is testing an antibiotic called minocycline against a placebo in 60 children with Fragile X. The Fragile X Research Foundation of Canada is studying the benefits of the same drug in 20 teenagers and young adults. Seaside Therapeutics is testing the drug arbaclofen , which it is calling STX209, against a placebo in 60 children and adults, to determine its safety and an appropriate dose. Some of those study participants will continue on the drug past the initial four-week trial. Roche is testing a similar drug it is calling RO4917523 against a placebo in 60 adults with Fragile X. Novartis recently completed testing the safety and dosing of a drug called AFQ056 against a placebo in 30 adults with Fragile X. Stanford University researchers are testing the drug donepezil, a medication that enhances the function of the brain chemical acetylcholine. This trial includes 50 patients ages 12 to 21. © 2010 NY Times Co.

By CHARLES Q. CHOI The infants and toddlers resemble cyborgs as they waddle and crawl around the playroom with backpacks carrying wireless transmitters and cameras strapped to their heads. Each has one camera aimed at the right eye and another at the field of view, and both send video to monitors nearby. When the video feeds are combined, the result is a recording in which red cross hairs mark the target of a child’s gaze. Scientists are using the eye-tracking setup to learn how children look at the world as they figure out how to interact with it. In the lab, children 5 months and older crawl and walk up, down and over an obstacle course of adjustable wooden slopes, cliffs, gaps and steps. And to add to the challenge, the subjects are sometimes outfitted with Teflon-coated shoes or lead-weighted vests. It may seem like the set for a new reality television show, but there are no prizes, except perhaps for the researchers. They hope to understand what prompts one child to respond to another, how infants coordinate their gaze with their hands and feet to navigate around obstructions or handle objects, and how these very young children adapt to changes, like those brought on by slippery footwear. The findings provided by these eye-trackers so far (the first light enough for children to wear) suggest that infants may be more capable of understanding and acting on what they see than had been thought. “Quick gazes at obstacles in front of them or at their mothers’ faces may be all they need to get the information they want. They seem to be surprisingly efficient,” said John Franchak, a doctoral candidate in developmental psychology at New York University. Copyright 2010 The New York Times Company

By Jason Palmer The brain appears to be a vastly interconnected network much like the Internet, according to new research. That runs counter to the 19th-Century "top-down" view of brain structure. A novel technique to track signals across tiny brain regions has revealed connections between regions associated with stress, depression and appetite. The research, which has been published in Proceedings of the National Academy of Sciences journal, may lead to a full map of the nervous system. Larry Swanson and Richard Thompson from the University of Southern California in Los Angeles, US, isolated a small section of a rat's brain in the nucleus accumbens - a brain region long associated with pleasure and reward. Their technique hinges on the injection of "tracers" at precise points in the brain tissue. These are molecules that do not interfere with the movement of signals across the tissue, but can be illuminated and identified using a microscope. What is new is that the researchers injected two tracers at the same point at the same time: one that showed where signals were going, and one that showed where they were coming from. The approach can show up to four levels of connection. If the brain has a hierarchichal structure like a large company, as neurology has long held, the "to" and "from" diagram would show straight lines from independent regions up towards a central processing unit: the company's boss. (C)BBC

by Greg Miller In children, an anxious temperament can be a warning sign. Kids who are painfully shy and nervous are more prone to anxiety disorders and depression later in life, and they're more likely to self-medicate with alcohol and other drugs. But what causes a child to have an anxious temperament in the first place? A new study with monkeys finds that an anxious temperament is partly heritable and that it's tied to a particular brain region involved in emotion. Children with an anxious temperament often freeze up when they meet a stranger or encounter a social situation they perceive as threatening, says Ned Kalin, a psychiatrist and neuroscientist at the University of Wisconsin, Madison. Kalin and his colleagues have found that some young monkeys do much the same thing. When a human "intruder" enters the room and approaches their cage without making eye contact, these anxious youngsters freeze in place and grow quiet. Their stress hormone levels spike, too. In the new study, published in the 12 August issue of Nature, Kalin and colleagues studied 238 young rhesus monkeys from a family of more than 1500 lab-raised monkeys with well-documented pedigrees. By analyzing the family connections among the young monkeys, which ranged from siblings to distant cousins, the researchers found that an anxious temperament was partly heritable, accounting for about 36% of the variability in individual monkeys' responses on the human intruder test (as measured by the reduction in movement and vocalization and increase in stress hormone levels). © 2010 American Association for the Advancement of Science.

By Katherine Harmon More than 26 percent of American adults were obese as of 2009—compared with less than 20 percent in 2000, according to a new report from the U.S. Centers for Disease Control and Prevention. And the number of U.S. states with more than 30 percent of their population topping a body mass index (BMI) of 30 tripled between 2007 and 2009. With this accelerating epidemic, researchers are looking for clues beyond daily diet and exercise to explain our propensity for extra poundage—and many are finding evidence in the very first stages of life. A growing number of analyses have found a convincing link among a heavier mother-to-be, increases in her baby's birth weight, and the child's later risk of obesity. In many past observational studies, however, basic genetics or environmental factors could be blamed for this association. A new study of 513,501 mothers and 1,164,750 of their children born across 15 years aimed to take genetics out of the equation by assessing maternal and infant weight only for those women who had more than one child. "By making comparisons of two or more infants born to the same mother, we were able to factor out the role of genetics," says David Ludwig, an associate professor of pediatrics, director of the Obesity Program at Children's Hospital Boston and co-author of the new study. Women who gained more than 24 kilograms during a pregnancy (which occurred in about 12 percent of pregnancies) added an average of 147.4 additional grams to their baby's birth weight than those who gained about 7.5 to 10 kilograms. © 2010 Scientific American,

By Janet Raloff Cash register and other receipts may expose consumers to substantial amounts of bisphenol A, a hormone-mimicking chemical that has been linked with a host of potential health risks, according to a trio of recent studies. Each study offers preliminary evidence that a large number of retail outlets print sales receipts on certain types of heat-sensitive, or thermal, paper that use BPA as a color developer. Two of the new studies also showed that the BPA coating easily rubs off onto fingers. And one found evidence that BPA from receipts may penetrate skin. The pollutant, which mimics the biological activity of estrogen, has been tied to health risks from behavioral problems in children to obesity and heart ailments. In animals, exposures in the womb put moms and their offspring at risk for later metabolic diseases. Based on growing concern about possible risks from ubiquitous exposure to BPA, especially in children, the federal government recently issued warnings to parents about where their families were most likely to encounter the chemicals. Store receipts did not make the list, although there have been hints for years that thermal receipt paper could be a rich source. Chemist John Warner learned about the chemistry of thermal- and pressure-sensitive papers while working for Polaroid years ago. Manufacturers lay a powdery coating containing BPA, a dye and a solvent onto one side of a piece of paper. When heat or pressure is applied, the coating’s constituents merge to release the ink’s color, he explains. © Society for Science & the Public 2000 - 2010

By Laura Sanders As people grow older, sad films seem sadder. In a recent study, people in their sixties felt sadder than people in their twenties did after viewing an emotionally distressing scene from a movie. This heightened emotional response to sorrow may reflect a greater compassion for other people and may strengthen social bonds, researchers propose. The finding is an important contribution to emotion studies because it adds to a growing body of work showing that emotions don’t deteriorate, says Stanford University psychologist Laura Carstensen, who was not involved in the research. “One of the important findings of this is that the emotion system is in no way broken in old age,” she says. To explore how feelings of sadness change with age, researchers led by Robert Levenson of the University of California, Berkeley brought 222 study participants into the laboratory to watch neutral, disgusting or sad movie clips. The volunteers made up three age groups: young people in their twenties, middle-aged people in their forties, and older people in their sixties. Before watching the movies, participants were hooked up to monitors that recorded physiological responses such as blood pressure, heart rate and breathing patterns. Levenson and his team chose two gut-wrenchingly sad scenes to elicit responses: In the first clip, from the movie 21 Grams, a mother is told of the deaths of her two young daughters. The second scene, from The Champ, depicts a young boy watching his father die after a boxing match. © Society for Science & the Public 2000 - 2010

By Bruce Bower At scientific meetings, psycho-biologist Colwyn Trevarthen often plays a video of a 5-month-old Swedish girl giving her mother a musical surprise. Blind from birth, the girl reaches for a bottle and laughs appreciatively as her mother launches into a familiar song about feeding blueberries to a bear. As in baby songs everywhere, Trevarthen says, each line of the Swedish tune runs about four seconds and each stanza lasts about 20. In a flash, the girl raises her left arm — an arm she has never seen — and begins conducting her mother’s performance. The baby, named Maria, moves her arm just before many of the song’s lines begin, leading her mother by about one-third of a second. In some cases, Maria synchronizes her hand movements with the rise and fall of her mother’s voice. Mom’s face glows in response to Maria’s playful directions. “Babies are born with a musical readiness that includes a basic sense of timing and rhythm,” declares Trevarthen, of the University of Edinburgh. Scientists have been finding that these chubby-cheeked cherubs heed a musical sense that moves them and grooves them long before they utter a word. Within a day or two after birth, babies recognize the first beat in a sound sequence; neural signs of surprise appear when that initial “downbeat” goes missing. Classical music lights up specific hearing areas in newborns’ right brains. Even more intriguingly, babies enter the world crying in melodic patterns that the little ones have heard in their mothers’ conversations for at least two months while in the womb (SN: 12/5/09, p. 14). © Society for Science & the Public 2000 - 2010

By Marla Cone, Emily Elert and Environmental Health News In a sweltering summer in New York City back in 1999, Yolanda Baldwin was eight months pregnant with her first child. She lived near a gas station and across the street from an intersection choked with exhaust-spewing cars and buses. Sometimes the air was so thick with pollution that she could see it, breathe it, smell it, even taste it. And she often wondered what it might be doing to her unborn child. Now Baldwin and several hundred other mothers whose sons and daughters have been monitored for a decade have an answer: Before children even take their first breath, common air pollutants breathed by their mothers during pregnancy may reduce their intelligence. A pair of studies involving more than 400 women in two cities has found that 5-year-olds exposed in the womb to above-average levels of polycyclic aromatic hydrocarbons, or PAHs, score lower on IQ tests. The compounds, created by the burning of fossil fuels, are ubiquitous in urban environments. In African American and Dominican communities of New York City, 249 children are being monitored for the effects of environmental contaminants until the age of 11. And across the Atlantic, in Krakow, Poland, another 214 children are participating in a parallel study. The findings in Poland, reported this spring, are strikingly similar to New York City’s: The children whose mothers had above-average exposure to PAHs scored about four points lower on IQ tests than children whose mothers had below-average exposure. © 2010 Scientific American,

By Nicholette Zeliadt Down's syndrome (DS) is an incurable, heritable disorder affecting an estimated 400,000 people in the U.S. It is characterized by impaired cognitive ability and abnormal physical growth. Whereas scientists have long known that DS is caused by inheriting an extra copy of all or part of chromosome 21, the underlying cause of the brain defects common in Down's patients has not been fully gleaned. Now, a collaborative team of scientists working with a mouse model of DS has discovered that just two genes are responsible for the majority of the brain abnormalities present in their animals. The scientists hope that their findings will help scientists understand brain defects in humans with the disorder as well as aid in the development of drugs to treat the cognitive impairment in Down's patients. Previous studies suggest that brain defects in DS mice occur very early, while the mice are still developing embryos. These defects result from abnormalities in how brain neurons communicate with each other—either via excitatory signals, which stimulate other neurons to communicate, or inhibitory signals, which act to prevent other neurons from firing. During embryonic development, the proper ratio of excitatory and inhibitory neurons is established for optimal brain function. These electrical circuits are the basis for memory formation and learning. Human chromosome 21 has more than 300 genes on it. Some of the features of DS—including cognitive deficits, heart defects, gastrointestinal problems and poor muscle tone—could therefore result from having either an additional copy of a single gene on chromosome 21; combinations of extra genes; or from the effects some redundant genes may exert on other chromosomes' genes. This complexity has significantly slowed the pace of researchers' attempts to understand the genetic basis of how such a diverse array of symptoms and abnormalities arise. © 2010 Scientific American,

Infants who will eventually be diagnosed with autism may be slower to eat solid foods and be fussier eaters, but their growth doesn't seem to be impaired compared with children without the disorders, a new British study suggests. Parents often describe infants diagnosed with autism spectrum disorders (ASD) as "slow feeders," and children with ASDs are often reported to eat a limited range of foods. Compared with 12,901 children without ASDs, 79 children ultimately diagnosed with an ASD were more likely to be slow eaters by six months, Dr. Pauline Emmett of the University of Bristol in England and her colleagues reported in Monday's online issue of the journal Pediatrics. Compared to the control group, children with ASD ate fewer vegetables, salads, and fresh fruit, but also consumed fewer sweets and carbonated drinks, the researchers said. About eight per cent of parents of autistic children reported that, as their kids reached 15 months, they were "very difficult to feed." That compared to about three per cent of kids without autism. Even though children with ASD consumed less of some vitamins and ate a more limited variety of foods, their intake of carbohydrates, protein, fats and total energy were similar to controls. No major differences in weight, height or body mass index were found up to age seven. © CBC 2010

by Lise Eliot IN 2010 we need to ask afresh just how deep the rabbit hole goes when it comes to gender politics - and how far we are from digging ourselves out. Our beliefs about differences between the sexes have an impact on society vastly out of proportion to the magnitude of those differences, from female scientists defending their mathematical and technical expertise to boys accused of lacking the communication and emotional skills to succeed at school. In truth, women are doing well in science: since 1970, the number of doctorates awarded to women in the US has increased five-fold in physics, nine-fold in computer science and 24-fold in engineering, according to the US Department of Education. And yet just last month we heard John Tierney of The New York Times appearing to echo former Harvard University president Larry Summers's claim that women may be intrinsically incapable of performing at the highest level in such fields. At the same time, boys are stepping away from pursuits like creative writing, foreign languages, art and singing in choirs as they hear they are not "hard-wired" for words or feelings. While young women get the message they can do anything, young men are put off careers in journalism, design, teaching, veterinary practice and psychotherapy, where they were once quite successful. When I set out to write my book Pink Brain, Blue Brain, I had little sense of the controversy surrounding gender differences. I was just a neuroscientist with a daughter and two sons, curious about how their brains might differ and how best to raise them. Now I see how little the science of gender differences has penetrated popular culture and am hoping to set the record straight on behalf of both sexes. © Copyright Reed Business Information Ltd.

by Dolly Krishnaswamy Under the vivid green canopies of the tropics, a young gorilla sneaks up behind another, yanks its hair, and dashes away with a toothy grin on its face. It may seem like harmless fun, but this game of tag has profound implications. In a new study, researchers say the behavior indicates that gorillas know the limits of their social status—and that they play tag to help even the score. Other studies have shown that nonhumans can sense unfairness. In 2005, for example, a group led by psychologist Sarah Brosnan of Yerkes National Primate Research Center in Atlanta reported that capuchin monkeys refused to exchange tokens with an experimenter for a cucumber if they saw a fellow monkey receiving a more desirable grape for its "money." But do animals also sense unfairness in more natural settings? To find out, behavioral biologist Marina Davila Ross of the University of Portsmouth in Hampshire, U.K., and colleagues watched videos collected over 3 years of gorillas at various zoos and reserves in Germany and Switzerland. Almost every afternoon, a couple of the gorillas would begin wrestling with each other. In some instances, gorillas hit their playmates and ran away. Most gorillas seemed to play this game of tag, though older mothers observed from the sidelines. Ross's team noticed a pattern in the play: Gorillas lower on the social ladder were usually the taggers. These gorillas were also twice as likely to instigate another round of the game, and they frequently bared their teeth—a possible indication that they were willing to bite the other gorilla. © 2010 American Association for the Advancement of Science.

By Melody Dye Subject 046M, for male, was seated nervously across from me at the table, his hands clasped tightly together in his lap. He appeared to have caught an incurable case of the squirms. I resisted the urge to laugh, and leaned forward, whispering conspiratorially. “Today, we’re going to play a game with Mr. Moo” —I produced an inviting plush cow from behind my back. “Can you say hi to Mr. Moo?” In the Stanford lab I work in with Professor Michael Ramscar, we study how children go about what is arguably the most vital project in their career as aspiring adults—learning language. Over the last several years, we’ve been particularly taken with the question of how kids learn a small, but telling piece of that vast complex: color words. We want to know how much they know, when they know it, and whether we can help them get there faster. 046M was off to a good start. I arranged three different color swatches in front of him. “Can you show me the red one?” He paused slightly, then pointed to the middle rectangle: red . “Very good!” I said, beaming. “Now, what about the one that’s blue?” The test was not designed to trip kids up. Far from it—we only tested basic color words, and we never made kids pick between confusable shades, like red and pink. To an adult, the test would be laughably easy. Yet, after several months of testing two-year olds, I could count my high scorers on one hand. Most would fail the test outright. 046M, despite his promising start, proved no exception. © 2010 Scientific American,

By Lindsey Tanner Want happier, more alert teenagers? Let them sleep in a little. A new study reveals that delaying the school day by 30 minutes results in teens who are less sleepy and depressed. Scientists say that teens tend to be in their deepest sleep around dawn, when they typically need to arise for school. Interrupting that sleep can leave them groggy. Giving teens 30 extra minutes to start their school day leads to more alertness in class, better moods, less tardiness, and even healthier breakfasts, a small study found. "The results were stunning. There's no other word to use," said Patricia Moss, academic dean at the Rhode Island boarding school where the study was done. "We didn't think we'd get that much bang for the buck." The results appear in July's Archives of Pediatrics & Adolescent Medicine. The results mirror those at a few schools that have delayed starting times more than half an hour. Researchers say there's a reason why even 30 minutes can make a big difference. Teens tend to be in their deepest sleep around dawn -- when they typically need to arise for school. Interrupting that sleep can leave them groggy, especially since they also tend to have trouble falling asleep before 11 p.m. © 2010 Associated Press/AP Online

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