By Bruce Bower Culture may hold a spatial place in thought. Social forces profoundly influence people’s ability to think about three-dimensional objects, a new study suggests. In tests of spatial ability, men traditionally outperform women. But men’s spatial superiority disappears among Northeast India’s Khasi villagers, say economist Moshe Hoffman of the University of California, San Diego and his colleagues. In Khasi society, youngest daughters inherit property, men forward earnings to wives or sisters, and females get as much schooling as males. Among neighboring Karbi villagers, men display spatial-thinking advantages over women, similar to those in many Western societies, Hoffman’s team reports in an upcoming Proceedings of the National Academy of Sciences. In Karbi society, males inherit and own land and receive more education than females. “These results show that nurture plays an important role in the gender gap in spatial abilities,” Hoffman says. But some researchers who study sex differences in thinking view the study skeptically. It’s not clear that the study in fact measured spatial ability, remarks psychologist Richard Lippa of California State University, Fullerton. Hoffman and colleagues measured spatial ability as the time taken to solve a four-piece jigsaw puzzle. But they didn’t assess volunteers’ accuracy at mentally rotating 3D figures and performing other spatial tasks, Lippa notes. © Society for Science & the Public 2000 - 2011

Keyword: Sexual Behavior; Evolution
Link ID: 15741 - Posted: 08.30.2011

By AMANDA SCHAFFER Ever since the New York Yankees Hall of Famer Lou Gehrig benched himself in 1939, never to return to the game, the ailment that now bears his name has stoked dread in the American imagination. Lou Gehrig’s disease — also known as amyotrophic lateral sclerosis, or A.L.S. — has afflicted well-known figures like the jazz great Charles Mingus, the physicist Stephen Hawking and the historian Tony Judt. The disease stems from the progressive deterioration of nerve cells, leading to a loss of control over voluntary muscles, difficulty breathing and swallowing, creeping paralysis and eventually death. There is no cure and no good treatment. Scientists are still unsure exactly what causes most cases. But in the journal Nature last week, researchers at Northwestern University identified a possible culprit: a cellular housekeeping agent that normally helps cells to clear away proteins that are damaged or misfolded. When the housekeeper fails, proteins seem to aggregate inside nerve cells, which may be contributing to their destruction. The finding has been hailed as a breakthrough by patient groups and scientists. The new work is “fueling great enthusiasm and interest,” said Dr. Amelie Gubitz of the National Institute of Neurological Disorders and Stroke, which helped finance the new work. Still, it is far from clear that this is the wellspring of A.L.S. There are at least a dozen processes that also might contribute to the demise of motor nerve cells, Dr. Gubitz noted. © 2011 The New York Times Company

Keyword: ALS-Lou Gehrig's Disease
Link ID: 15740 - Posted: 08.30.2011

By ALIYAH BARUCHIN FREETOWN, Sierra Leone — On a sweltering morning on a red-earth lane a few blocks from the largest mosque in this West African capital, Jeneba Kabba stands up. A tall, striking woman with a serious manner, Mrs. Kabba has been sitting under an awning in the outdoor classroom of a vocational training program for people with epilepsy. Every weekday, some 20 Sierra Leoneans, from teenagers to adults in middle age, gather here to learn skills like tailoring, weaving, tie-dyeing and soap-making, as well as reading — skills that, in this society, will give them a chance to earn a living. Mrs. Kabba, 30, a graduate of the program, is now a tutor. Her composure belies what she has survived. As a teenager she was taken to a traditional healer, who boiled herbs and made her inhale the fumes from a steam tent for hours. The treatment was supposed to drive out the demons thought to cause epilepsy; she nearly fainted and could have been burned. But worse was yet to come: She was forced to drink a two-liter bottle of kerosene. “Mi ches don cook,” she says in the Krio language, her voice faltering even now: “My chest started to boil.” Only a panicked trip to the hospital saved her life. Mrs. Kabba not only survived, but has been seizure-free for 10 years with the help of phenobarbital, one of the oldest anti-epileptic drugs and virtually the only one available here. And in a country where people with epilepsy are often considered uneducable, unemployable and unmarriageable, Mrs. Kabba teaches, is happily married and has a child. © 2011 The New York Times Company

Keyword: Epilepsy
Link ID: 15739 - Posted: 08.30.2011

By Nicole Gray A mother's age is often considered a genetic risk factor for offspring, but research is now pointing the finger at fathers, too—particularly when it comes to the mental health of their progeny. Males may have the advantage of lifelong fertility, but as they grow older, the rate of genetic mutations passed on via their sperm cells increases significantly—putting their children at increased risk for psychiatric disorders, especially autism and schizophrenia. Two recent studies support this link at least associatively, but experts remain uncertain if age is the cause of these problems. The Malaysian Mental Health Survey (MMHS) results, which were published online in March 2011, for instance, revealed that people with older parents as well as those whose fathers were at least 11 years older than their mothers, were at increased risk for certain mental health disorders, including anxiety, depression, obsessive-compulsive disorder and phobias. Offspring whose fathers were 19 or younger when the child was born had just a 9 percent prevalence of mental health disorders. Regardless of paternal age, however, if the father was 11 years or older than the mother, that rate jumped to 24 percent. The greatest risk of mental health disorders—42 percent—was seen in the children of fathers aged 50 and older, with wives at least 11 years younger than their husbands. The link between paternal age and increased risk of mental illness has long been recognized by practitioners, but researchers are beginning to unravel more details: "We have known that the children of older men have higher susceptibility to sporadic disease since the 1970s, but there has been an explosion of research in this area," says Dolores Malaspina, a professor of psychiatry and environmental medicine at New York University and a leader in the field of paternal age-related schizophrenia (PARS). © 2011 Scientific American,

Keyword: Schizophrenia; Autism
Link ID: 15738 - Posted: 08.30.2011

by Patti Neighmond We've all heard the theory that some students are visual learners, while others are auditory learners. And still other kids learn best when lessons involve movement. But should teachers target instruction based on perceptions of students' strengths? Several psychologists say education could use some "evidence-based" teaching techniques, not unlike the way doctors try to use "evidence-based medicine." Psychologist Dan Willingham at the University of Virginia, who studies how our brains learn, says teachers should not tailor instruction to different kinds of learners. He says we're on more equal footing than we may think when it comes to how our brains learn. And it's a mistake to assume students will respond and remember information better depending on how it's presented. For example, if a teacher believes a student to be a visual learner, he or she might introduce the concept of addition using pictures or groups of objects, assuming that child will learn better with the pictures than by simply "listening" to a lesson about addition. In fact, an entire industry has sprouted based on learning styles. There are workshops for teachers, products targeted at different learning styles and some schools that even evaluate students based on this theory. This prompted Doug Rohrer, a psychologist at the University of South Florida, to look more closely at the learning style theory. When he reviewed studies of learning styles, he found no scientific evidence backing up the idea.

Keyword: Learning & Memory
Link ID: 15737 - Posted: 08.30.2011

by Brooke Borei Just one encounter with an aroma can sear the scent into your memory for years. The same thing happens in rats, and researchers from the University of Bordeaux in France have exploited this to gain important insight into memory formation. When the brain encounters an odor, it temporarily saves the data in the banana-shaped hippocampus. But it is the frontal cortex that eventually encodes the memory into long-term storage. To decipher how that process unfolds, neurobiologist Bruno Bontempi and colleagues took advantage of a rather rude behavior in rats: The rodents often smell the breath of their fellow creatures to determine whether a new food is safe to eat. A single encounter can generate a lasting memory of the agreeable meal. In their study, Bontempi’s team fed cumin-spiced food to a set of rats and then introduced them to another group, whose frontal cortex had been temporarily cut off from communication with the hippocampus. One week later, the altered rats still enjoyed grub flavored with the spice, as expected. A month out, however, their preference for cumin had vanished—confirmation that long-term memories cannot form without a link between the hippocampus and the frontal cortex. Bontempi proposes that the hippo­campus tags cells in the cortex at the moment of a memory-generating experience. Breaking communication between the brain regions may interfere with tagging and subsequently handicap long-term memory. For rats, that means forgetting a morsel is safe. © 2011, Kalmbach Publishing Co.

Keyword: Learning & Memory
Link ID: 15736 - Posted: 08.29.2011

By James Gallagher Health reporter, BBC News People with psoriasis have nearly three times the normal risk of stroke and abnormal heart rhythm, according to scientists in Denmark. A study of 4.5 million people, published in the European Heart Journal, showed the highest risk was in young patients with severe psoriasis. Researchers believe this may be because the skin and blood vessels may share similar sources of inflammation. The Stroke Association said this should not be an immediate cause for concern. Skin cells are normally replaced every three to four weeks but, in patients with psoriasis, that process can be greatly speeded up. It can take between just two and six days, resulting in red, flaky, crusty patches on the skin. The condition affects 2% of people in the UK and the cause is unknown. Researchers analysed data from everyone in Denmark between 1997 and 2006 - 36,765 had mild psoriasis and 2,793 had the severe form of the condition. In patients under 50 with mild psoriasis, the risk of abnormal heart rhythm - atrial fibrillation - increased by 50%. The risk of ischaemic stroke increased by 97%. BBC © 2011

Keyword: Stress; Stroke
Link ID: 15735 - Posted: 08.29.2011

By Bruce Bower LAS VEGAS — Recent economic woes in the United States may have triggered a temporary upturn in the use of harsh parenting methods by mothers carrying a particular gene variant. Mothers who inherited either one or two copies of a particular form of the dopamine D2 receptor gene, dubbed DRD2, cited sharp rises in spanking, yelling and other aggressive parenting methods for six to seven months after the onset of the economic recession in December 2007, sociologist Dohoon Lee of New York University reported August 22 at the American Sociological Association’s annual meeting. Hard-line child-rearing approaches then declined for a few months and remained stable until a second drop to pre-recession levels started around June 2009, the research showed. Mothers who didn’t inherit the gene variant displayed no upsurge in aggressive parenting styles after the recession started, Lee and his colleagues found. As the recession progressed, mothers with the critical DRD2 variant apparently adjusted to tougher economic times enough to allow for a return to pre-recession parenting practices, Lee proposes. Economic uncertainty may prompt harsh parenting in genetically predisposed individuals as much as economic hardship and poverty do, Lee said. © Society for Science & the Public 2000 - 2011

Keyword: Sexual Behavior; Genes & Behavior
Link ID: 15734 - Posted: 08.29.2011

By Deborah Kotz, Globe Staff My three kids have been slacking off all summer -- on their regular bedtime that is. My 11-year-old’s bedtime shifted from 8:30 to 9:30 p.m. over the past two months, while my 13-year-old heads to bed well after 10:30, instead of his usual 9 p.m. bedtime. And I don’t even know when my 15-year-old powers down her laptop since it’s well after I’m asleep. Like many parents, I’m wondering what I should do to get my kids back to their earlier schedules during the days before the school year starts. Dr. Dennis Rosen, associate medical director of the center for pediatric sleep disorders at Children’s Hospital Boston, gave me some helpful advice. First off, he told me, I have to progressively march back their wake-up time rather than howling at them to go to bed earlier. “Give it at least a day for every hour that their bedtime is off,” Rosen advised. “If they’ve been waking up at 9 a.m. on a regular basis and they need to wake up at 6 a.m. for school, you’ll need three days to get them back on track,” waking them an hour earlier each morning for three consecutive days. Kids will be less cranky if you shift them even more gently, by 15- to 30-minute increments each day -- if you have the time before the school year starts. “Consistency is really important,” said Rosen. “Don’t want to fall into the trap of letting teens go to bed late and sleep in on the weekends” either or after the school year starts. © 2011 NY Times Co.

Keyword: Sleep
Link ID: 15733 - Posted: 08.29.2011

by Greg Miller The amygdala is a brain region best known for regulating emotion. But a new study reveals a previously unknown talent: recognizing animals. Researchers asked 41 epilepsy patients who'd had electrodes implanted in their brains in preparation for surgery to watch a computer monitor as 100 photos of people, animals, landmarks, and objects flashed onscreen. After analyzing the responses of 1445 neurons in the amygdala and neighboring regions, the team reports today in Nature Neuroscience that the right amygdala (but no other region) contains neurons that respond specifically to photos of animals. These neurons fired in response to animals but not people (not even a young Brad Pitt, as shown above), regardless of the angle or distance from which the shot was taken, and as a group they showed no preference for any particular category of animal, be it bird or mammal, dangerous, or potentially delicious. The researchers speculate that these responses reflect the importance of animals as both predators and prey in our evolutionary past. © 2010 American Association for the Advancement of Science

Keyword: Vision; Attention
Link ID: 15732 - Posted: 08.29.2011

Erika Check Hayden Vaccines are largely safe, and do not cause autism or diabetes, the US Institute of Medicine (IOM) said in a report issued today. This conclusion followed a review of more than 1,000 published research studies. "We looked very hard and found very little evidence of serious adverse harms from vaccines," says Ellen Wright Clayton, chairwoman of the reporting committee and director of the Center for Biomedical Ethics and Society at Vanderbilt University in Nashville, Tennessee. "The message I would want parents to have is one of reassurance." The report, commissioned in 2009 by the US Health Resources and Services Administration, covers the eight vaccines that comprise the majority of claims filed with the National Vaccine Injury Compensation Program (VICP), which compensates people for adverse health effects from any of 11 vaccines. The eight vaccines under review were those for chickenpox; influenza; hepatitis B; human papillomavirus; diphtheria, tetanus and pertussis (DTaP); measles, mumps and rubella (MMR); hepatitis A; and meningococcal disease. According to the report, evidence "convincingly supports a causal relationship" for only 14 specific adverse effects, including a range of infections associated with the chickenpox vaccine; brain inflammation and fever-induced seizures related to the MMR vaccine; allergic reactions to six of the vaccines and fainting or local inflammation caused by injection of any of them. The report noted that many of the more serious events, such as those linked to the chickenpox and MMR vaccines, only occur in children with weakened immune systems. © 2011 Nature Publishing Group,

Keyword: Autism
Link ID: 15731 - Posted: 08.27.2011

by Wendy Zukerman A SEXUAL development disorder in baby boys may be due to the absence of a hormone-production pathway identified in wallabies. The finding could help diagnose cases of ambiguous genitalia. One in 4500 babies has gene mutations that disrupt normal development of testes or ovaries in the womb. These children can be born with external genitalia that do not look typically female or male. In humans, normal development of the testes relies on two male hormones - testosterone and dihydrotestosterone (DHT). The latter is the more potent, and is produced when testosterone is broken down. Wallabies and some rodents are known to be able to make DHT via two different routes, one of which bypasses testosterone completely. The process works by converting cholesterol, the precursor to testosterone, directly into DHT. To find out whether a similar "back door" pathway exists in humans, Anna Biason-Lauber and her colleagues at the University Children's Hospital Zurich in Switzerland investigated the genetic make-up of a family, three of whom have ambiguous genitalia. As these individuals were all able to produce DHT from testosterone, multiple attempts to diagnose the cause of their symptoms had failed. © Copyright Reed Business Information Ltd.

Keyword: Sexual Behavior; Development of the Brain
Link ID: 15730 - Posted: 08.27.2011

Sandrine Ceurstemont, video producer If you're familiar with the spinning dancer illusion, you'll know that it can be hard to perceive which way an object is rotating. But now a new animation by psychophysiologist Marcel de Heer shows that a single moving image can appear to move in three different ways. Watch the animation above. How do the stingrays seem to move? According to de Heer, most people will see them swimming up and down, with their tail always away from us. But in the middle of the animation, as the stingrays turn sideways, their true motion is revealed. The one on the left was actually rotating clockwise while the one on the right was turning counterclockwise. Did you see them spinning or swimming? When we look around us, our visual system assesses the angle of objects to infer the perspective of the scene. But because of the stingrays' shape and two-dimensional striped pattern, it's hard to determine the point of view. This leads to ambiguous motion perception with several plausible alternatives. If you watch this animation for long enough, the stingrays' motion may even flip between the different possibilities. © Copyright Reed Business Information Ltd.

Keyword: Vision
Link ID: 15729 - Posted: 08.27.2011

by Caroline Williams Pythons, boas and pit vipers (the family that includes rattlesnakes) see the world pretty much as we do, but with a twist: they can "see" in infrared too. This allows them to track their prey by their body heat from up to a metre away. They do this using relatively simple organs, called pits, which lie near their nostrils. These differ slightly among different snakes but are always a small dip containing a membrane that is packed with heat-sensitive nerve endings which act as infrared receptors. The pit organs were first described in 1952 but it was only last year that the specific protein channels that react to heat were identified (Nature, vol 464, p 1006). These are found on nerve cells that are part of the sensory system that detects touch and temperature, and registers pain. Yet while this is completely separate from the visual system, both sets of information end up in the same place: a part of the brain called the optic tectum. "There, the two maps of space - visual and infrared - merge into one," says Michael Grace, a neuroscientist investigating pit viper thermal sensing at the Florida Institute of Technology in Melbourne. Grace speculates that this allows the snake to see in infrared and visible light at the same time, or to switch between one and the other. When hunting in a dark burrow, for example, it can use infrared to hunt its prey and to find its way to the warmer air at the surface of the burrow, and then return to regular vision when it emerges into a hot desert day where there are few differences in temperature. The snakes may be able to use both senses at once in early morning, when there is enough light to see and it is still cool enough for its warm-blooded prey to pop out as being much hotter than their surroundings. © Copyright Reed Business Information Ltd.

Keyword: Pain & Touch; Vision
Link ID: 15728 - Posted: 08.27.2011

By Matt McGrath Science reporter, BBC World Service Sexual relations between ancient humans and their evolutionary cousins are critical for our modern immune systems, researchers report in Science journal. Mating with Neanderthals and another ancient group called Denisovans introduced genes that help us cope with viruses to this day, they conclude. Previous research had indicated that prehistoric interbreeding led to up to 4% of the modern human genome. The new work identifies stretches of DNA derived from our distant relatives. In the human immune system, the HLA (human leucocyte antigen) family of genes plays an important role in defending against foreign invaders such as viruses. The authors say that the origins of some HLA class 1 genes are proof that our ancient relatives interbred with Neanderthals and Denisovans for a period. At least one variety of HLA gene occurs frequently in present day populations from West Asia, but is rare in Africans. The researchers say that is because after ancient humans left Africa some 65,000 years ago, they started breeding with their more primitive relations in Europe, while those who stayed in Africa did not. BBC © 2011

Keyword: Evolution; Neuroimmunology
Link ID: 15727 - Posted: 08.27.2011

By Nathan Seppa Just in time to combat the obesity epidemic sweeping the United States, a surgery called gastric bypass is riding a host of molecular and clinical findings to emerge as the preferred operation for severely overweight people. There is no shortage of patients; fully one-third of U.S. adults are now obese. Gastric bypass has gained popularity in part because it takes the pounds off. The operation leaves the stomach smaller, meaning a patient gets full faster, eats less and loses weight at a steady pace. Other common obesity surgeries have those effects too, but gastric bypass also reverses type 2 diabetes in most people, an outcome that bordered on alchemy when first noticed years ago. New research clarifies the molecular players that make this medical sleight of hand possible, as well as revealing other potential payoffs of the digestive changes — less heart disease, fewer breathing problems and lower blood pressure. Electing to have major surgery is a tough call; gastric bypass doesn’t always succeed. Patients can backslide, regaining lost weight. And about 10 percent of the surgeries have complications that can result in infections, blood clots or the need for repeat surgery. But many who witness the effects of gastric bypass firsthand suggest that the hard evidence has now tipped the scales in favor of the operation. © Society for Science & the Public 2000 - 2011

Keyword: Obesity
Link ID: 15726 - Posted: 08.27.2011

By Jeremy Laurance, Health Edtior Dieting is harder than you think. If you cut out a chocolate bar each day you will lose only one-third of the weight that experts had thought. For decades, doctors have based their advice to those who want to lose weight on the assumption that cutting 500 calories a day will see the weight fall off at the rate of 1lb a week. "This is wrong," Kevin Hill, of the National Institutes of Health in the United States, said. "It does not happen." The error has arisen because the calculation did not take account of changes in metabolism as weight falls. The body adjusts to reductions in energy intake (calories eaten) by slowing its energy output (calories expended). The result is that forgoing that daily chocolate bar containing 250 calories will lead to about 25lb of weight loss if it is sustained for three years, much less than the 78lb predicted by the old dieting assumption. A more sophisticated measure of weight loss, which takes account of metabolic changes and of differences between fat and thin people, has been developed by Dr Hill and colleagues of the National Institute of Diabetes and Digestive and Kidney Diseases. It shows that heavier people tend to lose weight faster than lighter people on the same diet, though they will take longer to reach the target weight than those who weigh less to begin with. Most people on a diet achieve their maximum weight loss after six to eight months and it has been assumed this is a natural "plateauing" effect, resulting from slowed metabolism. But evidence shows that people find it hard to stick to a diet for longer than six months and that is why they stop losing weight. Body-weight plateauing occurs much later, after two to three years. ©independent.co.uk

Keyword: Obesity
Link ID: 15725 - Posted: 08.27.2011

National Institutes of Health researchers have found that Parkin, an important protein linked with some cases of early-onset Parkinson’s disease, regulates how cells in our bodies take up and process dietary fats. Parkinson’s disease is a complex, progressive, and currently incurable neurological disorder characterized by shaking, stiffness, slowed movement, and impaired balance. Parkinson’s primarily affects people over 50, but in about 5 to10 percent of cases it occurs in people as young as their 20s. This form of the disease, which affects actor, author, and Parkinson’s activist Michael J. Fox, is known as early-onset Parkinson’s. Parkin mutations are present in as many as 37 percent of early-onset Parkinson’s cases. However, laboratory mice with defective Parkin do not display obvious signs of the disease. This preliminary study, which will appear online in the Journal of Clinical Investigation on Aug. 25, suggests defective Parkin may indirectly contribute to the development of some early-onset Parkinson's by changing the amount and types of fat in people’s bodies. The research team, composed of scientists from the NHLBI and the NIH’s National Institute of Neurological Disorders and Stroke, observed that mice with defective Parkin did not gain weight in response to a high-fat laboratory diet, as regular mice typically do. When the researchers examined several organs of the Parkin-defective mice, they noticed that the cells contained low levels of certain proteins that transport fat in the body. In contrast, normal mice that were fed the same high-fat diet had high levels of these fat-carrying proteins, as well as high levels of Parkin, suggesting that Parkin is involved in fat transportation.

Keyword: Parkinsons; Obesity
Link ID: 15724 - Posted: 08.27.2011

by Sara Reardon Contrary to popular belief, ostriches don't sleep with their heads in the sand. In fact, to all appearances, they never sleep at all: their eyes stay open, although they appear to doze off from time to time. To learn more about the sleep patterns of this unusual bird, researchers captured six ostriches in South Africa and measured their brain wave patterns with data loggers while they slept They expected the brain waves to look like those of other birds and mammals, which cycle between two patterns: deep sleep and rapid eye movement (REM). When the loggers showed that the ostriches were in deep sleep, the birds looked entirely alert. But when they entered another sleep cycle, their heads started to droop. This second brainwave pattern wasn't classic REM, but a unique hybrid of REM and deep sleep patterns, the researchers report this week in PLoS ONE. The only other animal to show this pattern is the platypus, a member of an ancient group of egg-laying mammals known as monotremes. As ostriches are an ancient type of bird, this similarity suggests that the separation between REM and deep sleep may have evolved recently in birds and mammals. One can only speculate on whether ostriches and platypuses have similar dreams, too. © 2010 American Association for the Advancement of Science.

Keyword: Sleep; Evolution
Link ID: 15723 - Posted: 08.27.2011

Researchers at the University of Calgary have documented serious health complications in multiple sclerosis patients who travelled outside of Canada to undergo a controversial treatment for their disease. Many MS patients have travelled overseas to find clinics willing to provide the treatment invented by Italian physician Paolo Zamboni, which uses balloon angioplasty to open up blocked veins in the necks of those who suffer from the disease. The new study followed five patients who had the vein opening therapy and were treated in Calgary hospitals in October and November last year after complications from their surgeries. The lead author of the paper, Dr. Jodie Burton, admits that it is difficult to draw conclusions since there were only five patients involved and it's not known how many Canadians went to locations like the United States, Mexico, India, and Poland to have the procedure done. But she says the seriousness of the complications should serve as a — quote — "cautionary tale" to anyone considering having the procedure done. Burton says patients shouldn't be afraid to let their doctors know they had the treatment and physicians need to know what to watch for as a result. In June, the federal government announced it will hold early-stage clinical trials into the treatment. © The Canadian Press, 2011 © CBC 2011

Keyword: Multiple Sclerosis
Link ID: 15722 - Posted: 08.25.2011