by Sunita Reed You may have seen robotic fish, robotic dogs, and even robotic roaches. But you’ve probably never seen a robotic lizard that does four-legged pushups. Its creator is evolutionary ecologist Terry Ord. Ord’s interest in lizards and other animals began as a child growing up in Australia, where his family spent weekends and holidays on their property in Australia’s bush country. “Amongst the rock outcrops around the house, lizards defended territories with elaborate performances of pushups and other displays,” Ord recalls. “The spectacle evidentially had a lasting impression because I would devote my PhD research to deciphering what exactly it was they were saying to each other.” As a researcher, Ord spent weeks at a time observing the male yellow-chinned anole lizard. He noticed that it defended its territory against other males with two types of displays. One is the subtle headbob. The other display is done with the flap of skin under its chin called a dewlap. When extended, it looks like an inflated bright yellow balloon. These two actions comprise the information-rich message that means, “I’m tough, so back off!” But sometimes the lizards would do exaggerated four-legged pushups before they gave this regular message. Was it just another way of flexing their muscles or was it an alert signal that the mostly silent lizards used to get their neighbor’s attention before “talking”? Ord suspected the latter was the case, and decided that the best way to talk to a lizard…was to be a lizard. Ord was at University of California at Davis and worked with Judy Stamps on this project. He now works at Harvard as well. ©2008 ScienCentral

Keyword: Aggression; Sexual Behavior
Link ID: 12363 - Posted: 06.24.2010

By Sara Coelho When a teammate crashes into you playing soccer, you're likely to experience some pain. But if an opposing player hits you with the same amount of force, you'll hurt a lot more. That's the conclusion of a new study that finds that pain caused intentionally feels much worse than pain perceived as accidental. While thinking about the debate over the torture of prisoners at Guantanamo Bay, psychologist Kurt Gray of Harvard University wondered whether the intent to deliver pain mattered. "Perhaps without this malicious intention, torture would not hurt as much," he says. Gray and Harvard colleague Daniel Wegner tested the hypothesis on 43 student volunteers, most of them female. Each volunteer was paired with a partner, who, unbeknownst to the volunteer, was a part of the research team. The volunteers were asked to perform several tasks chosen by the partner from a pair of options. One of the choices was between gauging the pain of electric shocks delivered by a stimulator tied to the volunteer's wrist (on a scale of 1 to 7) and evaluating the relative pitch of different sounds. In one set of experiments, the partner selected the painful task whenever the shock or pitch choice came up; as a result, the volunteers felt that the partner was intentionally harming them. In the other set of experiments, the volunteers still received electric shocks, but they were told that the partner was not responsible. © 2008 American Association for the Advancement of Science.

Keyword: Pain & Touch
Link ID: 12362 - Posted: 06.24.2010

By Erik Stokstad The movie Jurassic Park gave advanced, birdlike dinosaurs a fearsome reputation--swift, intelligent, and deadly. Now it turns out that they had a softer side. Researchers report that males in three species were stay-at-home dads that incubated the eggs in their nests. There's plenty of evidence to suggest that dinos baby-sat their offspring. A predatory dinosaur called Oviraptor, for example, was discovered in the Gobi Desert in 1993, its fossilized remains protecting a brood of eggs. In addition, dinosaurs' closest living relatives, birds and crocodiles, display nesting behavior: Female crocs guard the eggs, whereas in birds the gender of the stay-at-home-parent depends on the species. But whether male or female dinos had nest duty has remained a mystery. For the new research, paleontologist David Varricchio of Montana State University in Bozeman compared three species of birdlike dinosaurs--Oviraptor, Citipati, and Troodon--with birds and crocodiles. All three types of dinosaurs were found on nests, and those nests contain large clutches of eggs, as many as 30 each. Varricchio and his colleagues investigated whether they could discern the nesting behavior from the relationship of the clutch size and the animal's body size. Measurements in 433 living birds and crocodiles revealed that, for a given body size, species in which males took care of the nest tended to have the largest clutches. The next-largest clutches were cared for by mothers. Mom-dad partnerships had the smallest clutches. Extrapolated to dinosaurs, the data revealed a pattern of paternal care in the ancient beasts. © 2008 American Association for the Advancement of Science.

Keyword: Sexual Behavior
Link ID: 12361 - Posted: 06.24.2010

by Ewen Callaway For a 22-year-old woman known as AW, denim evokes feelings of depression, disgust and worthlessness. Corduroy causes confusion, and silk provides utter contentment. She is one of two people known to experience a newly discovered form of synaesthesia, where textures give rise to strong emotions. HS, another young woman who experiences tactile-emotion synaesthesia, gets no kick out of denim. Fleece and dry leaves disgust her, while the touch of tennis balls, fresh leaves and sand are heaven. Other forms of synaesthesia include numbers and letters that evoke colours, shapes that evoke tastes shapes and colours with their very own fragrances. AW and HS's sensations, unusual though they may seem, are an extreme form of the positive feelings most people associate with a soft blanket or the aversion to sharp knives and jagged rocks, says V. S. Ramachandran, a neuroscientist at the University of California, San Diego. "We have an affinity for fur because when were evolving in the ice age, we needed coats," he says. "This is the architecture on which [tactile-emotion synaesthesia] is built." A mental mishmash between touch and emotion could underlie metaphors such as sharp criticism and a rough night, he says. "Synaesthesia is a quirky example of a mechanism we all have for generating metaphors," he says. © Copyright Reed Business Information Ltd

Keyword: Pain & Touch
Link ID: 12360 - Posted: 06.24.2010

By Janet Raloff On December 18, a National Research Council panel told the Environmental Protection Agency that sufficient data exist to begin assessing the potential health risks posed by phthalates, among the most ubiquitous pollutants on the planet. At the same time, the NRC panel strongly recommended that the agency adopt a “paradigm shift” in the way it assesses the chemicals’ toxicity to humans. Instead of evaluating each phthalate compound individually, EPA should begin assessing risks from likely combos of these and related chemicals — even if each chemical works differently, according to the panel’s new report. Phthalates are a widely used family of plasticizers and solvents. Owing to the chemicals’ presence in plastics, cosmetics, personal care products and even medicines, residues of these chemicals show up in everyone throughout the developed world. For more than a decade, studies in rodents have been demonstrating that exposures to phthalates early in life can perturb — in some cases derail — development of an animal’s reproductive organs (SN: 9/2/00, p. 152). Males are most sensitive, largely because these chemicals act as anti-androgens. That is, the chemicals lower concentrations of testosterone, the primary male sex hormone. Especially concerning: In females, phthalates can cross the placenta and pollute the womb. © Society for Science & the Public 2000 - 2008

Keyword: Hormones & Behavior; Sexual Behavior
Link ID: 12359 - Posted: 06.24.2010

A newly discovered class of neurons allows rats to identify the borders of their surroundings and helps them to build mental maps. These neurons, called border cells, join three other known classes of neurons that help us to find our way through space: place cells fire when we pass through fixed locations, letting us know where we are; head-direction cells fire when we face particular directions, acting as a compass; and grid cells fire when we're at specific points on a hexagonal grid that the brain superimposes on our surroundings. Neuroscientist Edvard Moser from the Norwegian University of Science and Technology in Trondheim and his colleagues first came across border cells in the entorhinal cortex of rat brains1. While recording the activity from single neurons, the team kept finding neurons that were linked to mental maps but that didn't act like any of the three known classes of mapping neurons. "We ignored them in the beginning," says Moser. Later, however, the researchers realized that they might have found border cells, a theoretically predicted2 class of neurons. Moser and his colleagues refocused their attention on how these neurons reacted as rats ran around small rooms. They found that the border cells would fire when rats approached walls — generally, each border cell was linked with a single wall, but some cells responded to several borders. © 2008 Nature Publishing Group

Keyword: Learning & Memory
Link ID: 12358 - Posted: 06.24.2010

By Susan Watts Doctors fear a new wave of the human form of "mad cow disease" is about to hit Britain, BBC Newsnight has learned. In the UK, 164 people have died of variant CJD, which originally came from cows infected with BSE, and all cases shared a version of a certain gene. But Newsnight has been told of a new case in a separate genetic group. The government's chief adviser on vCJD, Professor Chris Higgins, said estimates were that up to 350 people could become affected by this new type. He told Newsnight the new case had been diagnosed on a clinical basis as vCJD. Such cases can be officially confirmed only if further, more invasive, tests go ahead, such as a brain biopsy. What is of concern to doctors in the new case is that the individual concerned has a particular genetic make-up and it is the first case to appear of that type. There is a key gene linked to vCJD and 42% of the population have a version of that gene, known as MM. The number of human victims peaked in the year 2000 and there are now only a handful of cases a year. It looked like the disease had almost gone away, but this new case is from a group with a version of the gene called MV. This raises fears that the 47% of the population who have this gene are now at risk. Prof Higgins, chairman of the government's Spongiform Encephalopathy Advisory Committee, said: "Given that 160 to 170 MM individuals were infected, we would estimate the number of MV victims would be a maximum of 300 to 350, probably between 50 and 350." (C)BBC

Keyword: Prions
Link ID: 12357 - Posted: 12.18.2008

People who snore heavily or have sleep apnea burn more calories when resting when the condition is more severe, researchers have found. In sleep apnea and other sleep-related breathing disorders, the airways become partially or completely blocked during sleep. Signs include frequent snoring and fatigue during the day. Untreated, sleep apnea can lead to serious health problems, such as an increased risk of heart attack or stroke and accidents. In the December issue of the Archives of Otolaryngology (head and neck surgery, including ears, nose and throat), Dr. Eric Kezirian of the University of California, San Francisco, and his colleagues measured resting energy expenditure, or the number of calories burned while resting, for 212 adults suspected of having sleep-related breathing disorders. Obesity is a major risk factor for developing sleep-related breathing problems, and changes in body mass are linked with changes in the severity of sleep-disordered breathing, the researchers noted. "It is unclear whether weight gain is simply a cause of sleep-disordered breathing or whether sleep-disordered breathing may be associated with alterations in energy metabolism that, in turn, lead to weight gain and complicate the treatment of these two disorders that often coexist," the study's authors wrote. © CBC 2008

Keyword: Sleep
Link ID: 12356 - Posted: 06.24.2010

Parents may think that sugar makes children hyperactive, but it's a myth, say researchers who analyzed evidence on this and other festive medical folklore. For the Christmas issue of the British Medical Journal, Dr. Aaron Carroll and Dr. Rachel Vreeman of the Indiana University School of Medicine debunk common holiday myths that have little evidence in scientific studies or online. The pair said they did the study to remind people of the importance of keeping a healthy skepticism. "Only by investigation, discussion, and debate can we reveal the existence of such myths and move the field of medicine forward," they wrote. For example, the idea that sugar from sweets, chocolates and pop makes children hyperactive is most likely in parents' minds, the researchers said, based on their review of at least 12 studies. Parents were so convinced about the myth that when they think their children have been given a drink containing sugar (when it is actually sugar-free) they rated their children's behaviour as more hyperactive. © CBC 2008

Keyword: ADHD
Link ID: 12355 - Posted: 06.24.2010

When I first heard the term “restless leg syndrome” years ago, I thought it was a joke. It’s not an uncommon reaction. Over at the Freakonomics blog, Stephen J. Dubner saw a commercial about the disorder and thought it was a “Saturday Night Live” spoof. But the people who have the problem aren’t laughing. Restless leg syndrome is a neurological disorder characterized by unpleasant sensations in the legs — often described by people as burning or creeping or like insects crawling inside the legs. The condition, which appears to have a genetic basis, creates an uncontrollable urge to move around. The biggest problem with the condition is that lying down and trying to relax makes it worse. The National Institute of Neurological Disorders and Stroke estimates that restless leg syndrome, or R.L.S., affects as many as 12 million Americans. But the number is a source of debate. Some doctors believe the condition is often misdiagnosed as nervousness or insomnia or under-diagnosed, because sufferers don’t seek medical attention. However, two Dartmouth Medical School researchers have questioned whether “disease mongering” by drug companies has led to an increase in R.L.S. diagnoses. They acknowledge that symptoms can be severe enough to be disabling, but wonder if ad campaigns for drugs to treat the condition have convinced otherwise healthy people that they are sick. Copyright 2008 The New York Times Company

Keyword: Sleep
Link ID: 12354 - Posted: 06.24.2010

By BENEDICT CAREY The book is at least three years away from publication, but it is already stirring bitter debates over a new set of possible psychiatric disorders. Is compulsive shopping a mental problem? Do children who continually recoil from sights and sounds suffer from sensory problems — or just need extra attention? Should a fetish be considered a mental disorder, as many now are? Panels of psychiatrists are hashing out just such questions, and their answers — to be published in the fifth edition of the Diagnostic and Statistical Manual of Mental Disorders — will have consequences for insurance reimbursement, research and individuals’ psychological identity for years to come. The process has become such a contentious social and scientific exercise that for the first time the book’s publisher, the American Psychiatric Association, has required its contributors to sign a nondisclosure agreement. The debate is particularly intense because the manual is both a medical guidebook and a cultural institution. It helps doctors make a diagnosis and provides insurance companies with diagnostic codes without which the insurers will not reimburse patients’ claims for treatment. Copyright 2008 The New York Times Company

Keyword: Depression; Schizophrenia
Link ID: 12353 - Posted: 06.24.2010

By Timothy Brady and Adena Schachner Perception is mathematically impossible. This might seem like a bold statement—after all, you are perceiving these letters right now—but it’s nonetheless true. Imagine a black-and-white line drawing of a cube on a sheet of paper. Although this drawing looks to us like a picture of a cube, there are actually an infinity of other three-dimensional figures that could have produced the same set of lines when collapsed on the page. But we don't notice any of these alternatives. Happily for all of us, our visual systems have more to go on than just bare perceptual input. They use heuristics and short cuts, based on the physics and statistics of the natural world, to make the “best guesses” about the nature of reality. Just as we interpret a two-dimensional drawing as representing a three-dimensional object, we interpret the two-dimensional visual input of a real scene as indicating a three-dimensional world. Our perceptual system makes this inference automatically, using educated guesses to fill in the gaps and make perception possible. It turns out that our brains use the same intelligent guessing process to reconstruct the past, in addition to using it help perceive the world. Memory itself is not like a video-recording, with a moment-by-moment sensory image. In fact, it’s more like a puzzle: we piece together our memories, based on both what we actually remember and what seems most likely given our knowledge of the world. Just as we make educated guesses in perception, our minds’ best educated guesses help “fill in the gaps” of memory, reconstructing the most plausible picture of what happened in our past.

Keyword: Vision
Link ID: 12352 - Posted: 06.24.2010

By Neil H. Shubin I started teaching human anatomy at the same time my university renovated my laboratory. As it turns out, this coincidence could not have been more propitious. Teaching anatomy for the first time can be a struggle, and it is not just because there are an enormous number of names to learn. A glimpse inside the body reveals structures left inside of us during the course of evolution, which often seem a confused jumble, with arteries, nerves and other structures taking odd paths to get from one part of the body to another. While I was struggling to understand the body’s internal structures, I was given space in a 100-year-old building that needed to be renovated into a modern laboratory. When we opened the walls to look at the plumbing, wiring and other mechanicals, we saw a tangle that made no apparent sense; cables, wires and pipes took bizarre loops and turns throughout the building. Nobody in their right mind would have designed my building to conform to the snarled mess we saw when the wall was removed. Constructed in 1896, the utilities reflect an old design that has been jury-rigged for each renovation done over previous decades. If you want to understand the twisting pathways for a cable or a pipe, you have to understand their history and how they have been modified over the years. The same is true for structures in the human body. © 1996-2008 Scientific American Inc.

Keyword: Evolution
Link ID: 12351 - Posted: 06.24.2010

by Ewen Callaway Parasites getting you down? Then take Prozac - if you're a fish, that is. A behaviour-altering parasitic worm has been found to stymie its host's production of serotonin - the same brain chemical that Prozac and other mood-lifting drugs ramp up. While there are no plans to medicate infected fish in the wild, researchers hope to use psychiatric drugs to figure out how trematode worms alter the behaviour of California killifish, which live in coastal estuaries. "There are whole populations where almost 100% of the fish are infected," says Jenny Shaw, a parasitologist at the University of California in Santa Barbara, who led the study. Otherwise healthy infected killifish surface frequently, flashing their silver bellies. When infected, they are 30 times more likely to get eaten by birds than uninfected fish," she says. The parasite's effect on the fish's behaviour is no accident. When the birds defecate, they pass the worm's eggs on to water snails, which in turn spread the worm larvae back to the killifish, thus completing the peculiar lifecycle of Euhaplorchis californiensis. © Copyright Reed Business Information Ltd.

Keyword: Miscellaneous
Link ID: 12350 - Posted: 06.24.2010

Charles Burress, Chronicle Staff Writer Could Sudoku be a balm for anxious people? A new study suggests that intellectually demanding challenges like crossword puzzles or chess may be more successful at keeping worry-prone people from worrying than supposedly relaxing pastimes like watching TV or shopping. Contrary to theories that "as things get harder, anxious people fall apart, this suggests it's the opposite way around," said UC Berkeley psychologist Sonia Bishop, lead researcher on the study published online this week by Nature Neuroscience. The study showed that anxious people performed just as well as others when facing tasks that demanded concentration, but they took more time than others to complete tasks that were easier, Bishop said. Their slower response time to challenges not requiring full attention was accompanied by reduced blood flow to the prefrontal cortex, which serves as the brain's CEO in thinking, planning and active memory. The study indicated that anxious individuals have a weakened ability to block out distractions and that they might benefit from mindfulness training, which often uses meditation and stress-reduction exercises to help increase one's awareness and focus. "With some very popular therapies like mindfulness training, people aren't sure why they work," Bishop said. "This perhaps gives us a rationale for why they do." © 2008 Hearst Communications Inc.

Keyword: Attention; Stress
Link ID: 12349 - Posted: 06.24.2010

By ANAHAD O’CONNOR A recent column pointed out that some Americans, mostly those raised in the age before color television, dream only in black and white. But that observation raised another question — whether people who don’t see images during the day might see them when they shut their eyes at night. For people with normal vision, dreaming is intensely visual. The dream state typically involves vivid scenes and imagery, much of it drawing upon our daytime experiences and concerns (whether conscious or not). Auditory stimulation plays a small role, and the other senses, like taste and smell, are virtually absent. But studies led by a psychologist at the University of Hartford show that for the blind, depending on when in life they lost their sense of sight, the reverse seems to be true. People born without the ability to see report no visual imagery in their dreams, but they do experience a heightening of taste, touch and smell. They also report a higher percentage of dreams that involve mishaps related to traveling or transportation, perhaps reflecting one of their biggest daytime concerns: safely finding their way around. Although individual experiences vary, researchers say people who go blind before age 5 rarely experience visual imagery in their dreams. But those who lose their vision after age 5 often continue to see in their dreams, though the frequency and clarity diminish over time. Copyright 2008 The New York Times Company

Keyword: Sleep
Link ID: 12348 - Posted: 06.24.2010

By NICHOLAS BAKALAR People who are depressed are literally sick at heart: they have a significantly increased risk for cardiovascular disease, and no one knows exactly why. Now three new studies have tried to explain this, and they arrive at subtly different conclusions. The first, led by Dr. Mary A. Whooley of the Veterans Affairs Medical Center in San Francisco, studied 1,017 patients with coronary artery disease for an average of more than four years. Although the study found an association of depression with heart disease, when researchers statistically corrected for other medical conditions, disease severity and physical inactivity, the association disappeared. They concluded with a relatively straightforward explanation: depression leads to physical inactivity, and lack of exercise increases the risk for heart disease. The study appears in the Nov. 26 issue of The Journal of the American Medical Association. A second study, published Tuesday in The Journal of the American College of Cardiology, provides a different perspective. It included more than 6,500 healthy men and women with an average age of 51. Researchers tested them for depressive symptoms and followed them for an average of more than seven years. Copyright 2008 The New York Times Company

Keyword: Depression
Link ID: 12347 - Posted: 12.16.2008

Interview by DEBORAH SOLOMON Your forthcoming book, “How We Decide,” is the latest entry in a growing field that might be called the science of decision-making. How do you explain the fascination with decisions? For the first time, neuroscience can be applied to everyday life. The research on the neurotransmitter dopamine, for instance, can teach us why we play slot machines and overuse our credit cards. Are you a decisive person? No, I’m pathologically indecisive. I wrote the book because I would spend 10 minutes in the cereal aisle choosing between Honey Nut Cheerios and Apple Cinnamon Cheerios. Maybe indecisiveness is the price of being an intelligent human being who understands that actions have consequences. That would be a little too self-congratulatory for me. Indecisiveness means you’re not listening carefully enough to your emotions, which know what you really want and could be whispering, “Go for the Honey Nut Cheerios.” How is that idea any different from the gut decision-making that Malcolm Gladwelldescribes in “Blink”? Fast-blink decisions are not always useful. The brain is full of different tools, and you don’t want to use a hammer if the problem requires more than a blunt hit. Right now, as a consumer society in meltdown mode, aren’t we suffering from a surfeit of fast, unreflective decisions, i.e. spending? I think retail stores and mortgage brokers have become a little too adept at tickling our dopamine neurons, and credit cards don’t help. Copyright 2008 The New York Times Company

Keyword: Attention
Link ID: 12346 - Posted: 06.24.2010

Jennifer Viegas -- If your head is overheated, there's a good chance you'll yawn soon, according to a new study that found the primary purpose of yawning is to control brain temperature. The finding solves several mysteries about yawning, such as why it's most commonly done just before and after sleeping, why certain diseases lead to excessive yawning, and why breathing through the nose and cooling off the forehead often stop yawning. The key yawn instigator appears to be brain temperature. "Brains are like computers," Andrew Gallup, a researcher in the Department of Biology at Binghamton University who led the study, told Discovery News. "They operate most efficiently when cool, and physical adaptations have evolved to allow maximum cooling of the brain." He and colleagues Michael Miller and Anne Clark analyzed yawning in parakeets as representative vertebrates because the birds have relatively large brains, live wild in Australia, which is subject to frequent temperature swings, and, most importantly, do not engage in contagious yawning, as humans and some other animals do. © 2008 Discovery Communications, LLC.

Keyword: Emotions; Sleep
Link ID: 12345 - Posted: 06.24.2010

By Devin Powell When you hear that raspy, female voice coming down the hall, you know that your chain-smoking boss Susan is about to show up in your office. This ability to match a voice with a concrete identity is a complex mental task, thought to be the domain of only a few animals, including humans. But new research in horses suggests that they too evolved the skill. Most creatures have ways to recognize members of their own species. Hamsters sniff, birds listen for a song, and wasps look at facial markings. But researchers have struggled to nail down whether the animals are simply recognizing something familiar or whether they are connecting the stimulus to a specific individual. Behavioral biologists Leanne Proops, Karen McComb, and colleagues at the University of Sussex in the U.K. adapted a technique normally used to study human infants, who cannot verbalize their thoughts. In a common experiment, babies who stare longer at certain objects are assumed to be perplexed by them. Applying this idea to domestic horses, the researchers made a horse watch as a member of its herd was paraded in front of it and subsequently hidden behind a barrier. Proops then played a prerecorded horse whinny over a loudspeaker and watched the observing horse's response. When the call came from a different horse from the herd than the hidden one, the viewing horse seemed confused, looking up at the barrier faster and for 20% longer than when the whinny belonged to the paraded horse, the team reports online this week in the Proceedings of the National Academy of Sciences. The horses are not just reacting to the sound of the whinny, says Proops, who notes that the viewing horse could identify six different horses from its herd: "They understand that every voice is paired to a face." © 2008 American Association for the Advancement of Science.

Keyword: Language; Animal Communication
Link ID: 12344 - Posted: 06.24.2010