By Geoffrey Mohan Hyperactive brain cells firing together could be an early indicator of autism and developmental disabilities, a team of UCLA researchers has found. Networks of neurons were found to be firing in a highly synchronized and seemingly unrelenting fashion, even through sleep, in the brains of juvenile mice that have a genetic abnormality similar to one that causes mental retardation and autism symptoms in humans, according to the research published online Monday in Nature Neuroscience. Without independently firing neurons, the human brain would be about as functionally complicated as a digital switch. With it, we compose poetry and send robotic carts to Mars. "If you want to code information, you can’t just have all the cells fire together or not, because then that’s just binary. It goes up and down," said UCLA neuroscientist Carlos Portera-Cailliau, a lead author of the report. “But if you have billions of neurons, all firing independently or in small clusters, then you can code a lot of information.” That “de-synchronization” was greatly diminished in the neocortex of the juvenile mice that had been altered so that they lack the same protein known to cause mental retardation and autistic behaviors in humans. These so-called Fmr1 Knockout mice, named for the gene that is knocked out, exhibit autism behaviors, among them social deficits – they don’t go over and sniff and examine a new mouse introduced to the cage, like wild mice would. Copyright 2013

Keyword: Autism
Link ID: 18235 - Posted: 06.05.2013

by Kim Krieger The song of the cicada has been romanticized in mariachi music, used to signify summer in Japanese cinematography, and cursed by many an American suburbanite wishing for peace and quiet. Despite the bugs' ubiquity, scientists haven't uncovered how they sing so loudly—some are as noisy as a jet engine—and why they don't expend much energy doing it. But researchers reported in Montreal yesterday at the 21st International Congress on Acoustics that they now have the answer. The detailed mechanism of the cicada's song is far from fully understood, says Paulo Fonseca, an animal acoustician at the University of Lisbon who was not involved in the project. The work by the researchers "is innovative and paves our way to a better understanding of this complex system allowing such small animals to produce such powerful sound." Cicadas aren't just a natural curiosity. Small devices that produce extremely loud noises while requiring very little power appeal to the U.S. Navy, which uses sonar for underwater exploration and communication. Derke Hughes, a research engineer at the Naval Undersea Warfare Center in Newport, Rhode Island, says that the loudest cicadas can make a noise 20 to 40 dB louder than the compact off-the-shelf RadioShack speaker in his office using the same amount of power. Intrigued, he and his colleagues used microcomputed tomography)—a kind of CT scan that picks up details as small as a micron in size—to image a cicada's tymbal, which helps the insect make its deafening chirp. © 2010 American Association for the Advancement of Science

Keyword: Hearing; Sexual Behavior
Link ID: 18234 - Posted: 06.05.2013

Matt Kaplan Just as city slickers have faster-paced lives than country folk, so too do urban birds, compared with their forest-dwelling cousins. The reason, researchers report today, is that urban noise and light have altered the city birds’ biological clocks1. The finding helps to explain prior reports that urban songbirds adopt more nocturnal lifestyles2–4 — data that prompted Davide Dominoni, an ecologist at the Max Planck Institute for Ornithology in Radolfzell, Germany, to investigate whether the birds’ activity patterns were merely behavioural responses to busy cities or were caused by an actual shift in the animals' body clocks. For the study, published in Proceedings of the Royal Society B, Dominoni and his colleagues set up an experiment with European blackbirds (Turdus merula). The scientists attached tiny 2.2-gram radio-pulse transmitters to blackbirds living in Munich, Germany, as well as to those living in a nearby forest. The transmitters monitored the birds’ activity for three weeks. Dominoni found that whereas forest birds started their activity at dawn, city birds began 29 minutes earlier, on average, and remained active for 6 minutes longer in the evening. Keen to determine these differences were due to physiological changes, Dominoni collected blackbirds from both locations and placed them into light- and sound-proof enclosures. For ten days these enclosures were illuminated with a constant, dim light so the birds had no idea what time of day it was, and their activity patterns were monitored. © 2013 Nature Publishing Group,

Keyword: Biological Rhythms
Link ID: 18233 - Posted: 06.05.2013

By Piercarlo Valdesolo The posed stare-down is a staple of the pre-fight ritual. Two fighters, one day removed from attempting to beat the memories from each other, stand impossibly close, raise their clenched fists and fix their gaze on the other’s eyes as cameras click away. This has always seemed little more than a vehicle for media hype, but new research from psychologists at the University of Illinois suggests that there may be clues in this bit of theatre that predict the results of the fight to come. Specifically, the researchers hypothesized that there’s something about the fighters’ facial expressions in this standoff that reveal the competitive dynamics between them. A subtle, and perhaps unintentional, communication of submission from one fighter to the other. A recognition of the opponent’s power. The smile. Facial expressions have long been thought to be reliable indicators of a person’s true feelings. Indeed, in his book “The Expression of the Emotions in Man and Animals” Darwin suggested that such expressions have evolved precisely because they serve this important function. The smile has attracted much empirical attention and has generally been interpreted as a signal of an individuals’ immediate, as well as long-term, well-being. In a particularly interesting study, the frequency and “authenticity” of smiles in high school yearbook photos tended to predict higher levels of subjective well-being years later. But smiles can mean different things in different contexts. The researchers here were particularly interested in what a smile might mean when displayed between competitors. Instead of merely communicating a fighter’s good spirits, the researchers hypothesized that it would be a submissive signal that reveals a fighter’s reduced hostility and lower willingness to aggress towards the opponent. © 2013 Scientific American,

Keyword: Aggression; Emotions
Link ID: 18232 - Posted: 06.05.2013

Devin Powell A model helicopter can now be steered through an obstacle course by thought alone, researchers report today in the Journal of Neural Engineering. The aircraft's pilot operates it remotely using a cap of electrodes to detect brainwaves that are translated into commands.1 Ultimately, the developers of the mind-controlled copter hope to adapt their technology for directing artificial robotic limbs and other medical devices. Today's best neural prosthetics require electrodes to be implanted in the body and are thus reserved for quadriplegics and others with disabilities severe enough justify invasive surgery. "We want to develop something non-invasive that can benefit lots of people, not just a limited number of patients," says Bin He, a biomedical engineer at the University of Minnesota in Minneapolis, whose new results build on his previous work with a virtual thought-controlled helicopter.2 But He's mechanical whirlybird isn't the first vehicle to be flown by the brain. In 2010 a team at the University of Illinois at Urbana-Champaign reported an unmanned aircraft that flies a fixed altitude but adjusts its heading to the left or right in response to a user's thoughts.3 The new chopper goes a step further. It can be guided up and down, as well as left or right, and it offers more precise control. To move it in a particular direction, a user imagines clenching his or her hands — the left one to go left, for instance, or both to go up. That mental image alters brain activity in the motor cortex. Changes in the strength and frequency of signals recorded by electrodes on the scalp using electroencephalography (EEG), and deciphered by a computer program, reveal the pilot's intent. © 2013 Nature Publishing Group

Keyword: Robotics
Link ID: 18231 - Posted: 06.05.2013

By Susan Milius After death, male guppies can keep on siring offspring because females store sperm for so long. As a result, a living male in a stream in Trinidad can end up competing with long-gone fish from his grandfather’s generation. At its most posthumously successful, stored ghost sperm sired about one in four of the offspring among wild guppies released into a stream, evolutionary biologist Andrés López-Sepulcre of École Normale Supérieure in Paris and his colleagues report June 5 in Proceedings of the Royal Society B. Biologists have long known that female Poecilia reticulata guppies store sperm. The cells clump in little pockets in a female’s ovarian cavity and feed on sugars released by ovarian tissue. Storage in itself isn’t unusual, López-Sepulcre says. Some crabs, turtles, lizards, bats and other creatures preserve sperm for later use. Posthumous reproduction by stored sperm also isn’t unheard of. “The fun part of our study,” López-Sepulcre says, “is that you have males who are alive and males who are dead competing with each other.” Researchers deployed guppies in several streams as part of a study on evolutionary change. Every month researchers catch, check and release as many fish as possible to track deaths and births. They also genetically analyze parenthood of the fish. Female guppies give live birth to broods of two to about 10 youngsters, with not all sired by the same male. Females live about 15 months; males about three. © Society for Science & the Public 2000 - 2013

Keyword: Sexual Behavior; Evolution
Link ID: 18230 - Posted: 06.05.2013

By Scicurious Most people have heard of ECT: Electroconvulsive Therapy. A lot of people will immediately think of the scene during One Flew Over the Cuckoo’s Nest, which doesn’t give you a very good picture. People think of ECT and think of horrible seizures, something terribly dangerous. But it’s not like that anymore. Now, ECT is usually done during a light anesthesia as well as a muscle relaxant. The huge seizures don’t happen anymore, though it’s still uncomfortable to watch (that’s a warning for the video below). So while ECT is no longer horrifying, it’s not something to be taken lightly. Aside from the fact that you’re getting an induced seizure, there are side effects, often people have deficits in working memory for a while afterward. But for people with severe depression who are truly desperate, it’s sometimes their best hope. But while we know that, in many patients, ECT does work, we still don’t know HOW. There are lots of antidepressants on the market today. All of them currently act on neurotransmitters, chemical messengers in the brain, and most of them act, at least in part, on serotonin. But the problem is, antidepressants don’t work for everyone. In fact, about 60% of patients being treated for depression won’t respond to the first drug they are given, and require trials of several different different drugs. And, sadly, 20% of patients don’t respond to all of the drugs tried. That’s a lot of people. And those people, who have often exhausted all of the drug options, sometimes turn to ECT. © 2013 Scientific American

Keyword: Depression
Link ID: 18229 - Posted: 06.04.2013

By ANAHAD O'CONNOR The number of middle-aged men with prescriptions for testosterone is climbing rapidly, raising concerns that increasing numbers of men are abusing the powerful hormone to boost their libidos and feel younger, researchers reported on Monday. Testosterone replacement therapy is approved specifically for the treatment of abnormally low testosterone levels, a condition called hypogonadism. The hormone helps build muscle, reduce body fat and improve sex drive. But a study published in the journal JAMA Internal Medicine found that many men who get prescriptions for the hormone have no evidence of a deficiency at all. The new study is the largest of testosterone prescribing patterns to date, involving nearly 11 million men who were tracked through a large health insurer. The report showed that the number of older and middle-aged men prescribed the hormone has tripled since 2001. Men in their 40s represent the fastest-growing group of users. About half of men prescribed testosterone had a diagnosis of hypogonadism, and roughly 40 percent had erectile or sexual dysfunction. One third had a diagnosis of fatigue. The medical group that sets clinical guidelines for testosterone replacement therapy, the Endocrine Society, recommends treatment only in men who have unequivocally low testosterone levels. That finding requires a blood test. But the new report found that a quarter of men did not have their levels tested before they received the hormone. It was also unclear what proportion of men who did undergo testing actually had results showing a deficiency. Copyright 2013 The New York Times Company

Keyword: Hormones & Behavior
Link ID: 18228 - Posted: 06.04.2013

by Helen Thomson TWO years ago, Antonio Melillo was in a car crash that completely severed his spinal cord. He has not been able to move or feel his legs since. And yet here I am, in a lab at the Santa Lucia Foundation hospital in Rome, Italy, watching him walk. Melillo is one of the first people with lower limb paralysis to try out MindWalker – the world's first exoskeleton that aims to enable paralysed and locked-in people to walk using only their mind. Five people have been involved in the clinical trial of MindWalker over the past eight weeks. The trial culminates this week with a review by the European Commission, which funded the work. It's the end of a three-year development period for the project, which has three main elements. There is the exoskeleton itself, a contraption that holds a person's body weight and moves their legs when instructed. People learn how to use it in the second element: a virtual-reality environment. And then there's the mind-reading component. Over in the corner of the lab, Thomas Hoellinger of the Free University of Brussels (ULB) in Belgium is wearing an EEG cap, which measures electrical activity at various points across his scalp. There are several ways he can use it to control the exoskeleton through thought alone – at the moment, the most promising involves wearing a pair of glasses with flickering diodes attached to each lens. © Copyright Reed Business Information Ltd.

Keyword: Robotics
Link ID: 18227 - Posted: 06.04.2013

By JOHN MARKOFF JERUSALEM — Liat Negrin, an Israeli who has been visually impaired since childhood, walked into a grocery store here recently, picked up a can of vegetables and easily read its label using a simple and unobtrusive camera attached to her glasses. Ms. Negrin, who has coloboma, a birth defect that perforates a structure of the eye and afflicts about 1 in 10,000 people, is an employee at OrCam, an Israeli start-up that has developed a camera-based system intended to give the visually impaired the ability to both “read” easily and move freely. Until now reading aids for the visually impaired and the blind have been cumbersome devices that recognize text in restricted environments, or, more recently, have been software applications on smartphones that have limited capabilities. In contrast, the OrCam device is a small camera worn in the style of Google Glass, connected by a thin cable to a portable computer designed to fit in the wearer’s pocket. The system clips on to the wearer’s glasses with a small magnet and uses a bone-conduction speaker to offer clear speech as it reads aloud the words or object pointed to by the user. The system is designed to both recognize and speak “text in the wild,” a term used to describe newspaper articles as well as bus numbers, and objects as diverse as landmarks, traffic lights and the faces of friends. It currently recognizes English-language text and beginning this week will be sold through the company’s Web site for $2,500, about the cost of a midrange hearing aid. It is the only product, so far, of the privately held company, which is part of the high-tech boom in Israel. © 2013 The New York Times Company

Keyword: Vision; Robotics
Link ID: 18226 - Posted: 06.04.2013

By Felicity Muth If you grew up with brothers or sisters you will know that competition is a key part of childhood. Personally, I experienced competition for food resources (the last bar of chocolate), parental investment (attention) and other more unusual resources (the best colour of lego pieces). As we age, we continue competing, although what we compete for changes. We compete in sports, for partners and for jobs. Like humans, pretty much all other animals will compete in one way or another. Even if they live a solitary life they may be still competing indirectly with others. But, like humans, animals need to choose which battles are worth fighting, and how much effort to put into it. One obvious way of deciding when to bother competing with another is the absolute worth of the thing you’re fighting over. If you and a stranger stumbled across some money in the street, you might fight vigorously for a $100 note, but more half-heartedly for $5 (this is of course an example using some very money-driven and aggressive individuals). However, how much value an individual puts on an item’s worth is going to be somewhat subjective. If you’re poor and starving, you might invest more into fighting for $5 than someone who is not. Thus, most competitions will contain both objective and subjective aspects: the intrinsic worth of an object (large food items are better than small), and the individual’s state when they’re assessing that item. © 2013 Scientific American

Keyword: Aggression
Link ID: 18225 - Posted: 06.04.2013

By Rachel Ehrenberg The salad days of human evolution saw a dietary shift toward grasses and probably grass-fed animals, analyses of more than 100 fossilized teeth from eight species of ancient hominids indicate. “These changes in diet have been predicted,” says paleoanthropologist Richard Klein of Stanford University. “But it’s very nice to have some data, and these data support it very strongly.” Changes in the size and shape of jaws and teeth in both ancient hominids and their ape relatives point to changes in diet. The new study adds to these lines of anatomical evidence chemical analyses that look at different forms of carbon in the fossilized teeth. The ratio of two types of carbon in tooth enamel reflects diet, says geochemist Thure Cerling of the University of Utah, who spent weeks in a vault in the National Museum of Kenya collecting milligram-sized samples of tooth enamel for the analyses. Grasses, grasslike sedges and many other plants in hot, arid environments have evolved a trick that helps prevent water loss. The metabolic adjustment results in taking up more of a heavier form of carbon, known as carbon-13, than most trees and shrubs do. The tooth studies, which cover more than 3 million years and include specimens from southern, eastern and central Africa, found greater quantities of this heavier carbon in hominids that are closer to humans on the evolutionary tree. This pattern suggests that, compared with humans’ more ancient relatives, recent ones were eating more grass or more grass-feeding animals, like zebras. The analyses appear June 3 in the Proceedings of the National Academy of Sciences. © Society for Science & the Public 2000 - 2013

Keyword: Evolution; Obesity
Link ID: 18224 - Posted: 06.04.2013

By Aiden Arnold “…henceforth, space by itself, and time by itself, are doomed to fade away into mere shadows, and only a kind of union between the two will preserve an independent reality.” This now iconic quote spoken by Hermann Minkowski in 1906 captured the spirit of Albert Einstein’s recently published special theory of relativity. Einstein, in a stroke of mathematical genius, had shown that both space and time as independent mathematical constructs were mere illusions in the equations of relativity, conceding instead to a 4-dimensional construct which Minkowski adroitly termed space-time. While most people are familiar with the ensuing influence Einstein’s ideas had on both the academic and public conception of the physical universe, few people are aware a similar revolution against space and time is underway in the fields of experimental psychology and neuroscience. Spatial cognition is the study of how the mind’s cognitive architecture perceives, organizes and interacts with physical space. It has long been of interest to philosophers and scientists, with perhaps the biggest historical step towards our modern ideas occurring within Immanuel Kant’s Critique of Pure Reason (1781/1787). Kant argued that space as we know it is a preconscious organizing feature of the human mind, a scaffold upon which we’re able to understand the physical world of objects, extension and motion. In a sense, space to Kant was a window into the world, rather than a thing to be perceived in it. © 2013 Scientific American

Keyword: Learning & Memory; Development of the Brain
Link ID: 18223 - Posted: 06.04.2013

by David Robson NO CREVICE of the human experience is safe. Our deepest fears and desires, our pasts and our futures – all have been revealed, and all in the form of colourful images that look like lava bubbling under the skull. That, at least, is the popular conception of neuroscience – and it's worth big money. The USMovie Camera and the European Union are throwing billions of dollars at two new projects to map the human brain. Yet there is also a growing anxiety that many of neuroscience's findings don't stand up to scrutiny. It's not just sensational headlines reporting a "dark patch" in a psychopath's brain, there are now serious concerns that some of the methods themselves are flawed. The intrepid outsider needs expert guidance through this rocky terrain – and there's no better place to start than Brainwashed by Sally Satel and Scott O. Lilienfeld. Satel, a practising psychiatrist, and Lilienfeld, a clinical psychologist, are terrific sherpas. They are clear-sighted, considered and forgiving of the novice's ignorance. Their first stop is the fMRI scan – a staple of much brain research. Worryingly, the statistical techniques used to construct the images sometimes create a mirage of activity where none should exist. They have a telling example: one research team watching a salmon in an fMRI scanner as images of human faces were flashed at it saw its brain spark into life in certain shots – even though it was dead. © Copyright Reed Business Information Ltd.

Keyword: Brain imaging
Link ID: 18222 - Posted: 06.04.2013

Zoe Cormier Love really does change your brain — at least, if you’re a prairie vole. Researchers have shown for the first time that the act of mating induces permanent chemical modifications in the chromosomes, affecting the expression of genes that regulate sexual and monogamous behaviour. The study is published today in Nature Neuroscience1. Prairie voles (Microtus ochrogaster) have long been of interest to neuroscientists and endocrinologists who study the social behaviour of animals, in part because this species forms monogamous pair bonds — essentially mating for life. The voles' pair bonding, sharing of parental roles and egalitarian nest building in couples makes them a good model for understanding the biology of monogamy and mating in humans. Previous studies have shown that the neurotransmitters oxytocin and vasopressin play a major part in inducing and regulating the formation of the pair bond. Monogamous prairie voles are known to have higher levels of receptors for these neurotransmitters than do voles who have yet to mate; and when otherwise promiscuous montane voles (M. montanus) are dosed with oxytocin and vasopressin, they adopt the monogamous behaviour of their prairie cousins. Because behaviour seemed to play an active part in changing the neurobiology of the animals, scientists suspected that epigenetic factors were involved. These are chemical modifications to the chromosomes that affect how genes are transcribed or suppressed, as opposed to changes in the gene sequences themselves. © 2013 Nature Publishing Group

Keyword: Sexual Behavior; Epigenetics
Link ID: 18221 - Posted: 06.03.2013

By Ian Chant Kids are wildly better than adults at most types of learning—most famously, new languages. One reason may be that adults' brains are “full,” in a way. Creating memories relies in part on the destruction of old memories, and recent research finds that adults have high levels of a protein that prevents such forgetting. Whenever we learn something, brain cells become wired together with new synapses, the connections between neurons that enable communication. When a memory fades, those synapses weaken. Researchers led by Joe Tsien, a neuroscientist at the Medical College of Georgia, genetically engineered mice to have high levels of NR2A, part of a receptor on the surface of some neurons that regulates the flow of chemicals such as magnesium and calcium in and out of a cell. NR2A is known to be more prevalent in the brains of mammals as they age. The engineered mice, though young, had adult levels of NR2A, and they showed some difficulty forming long-term memories. More dramatically, their brains could barely weaken their synapses, a process that allows the loss of useless information in favor of more recent data. A similar process may govern short-term memories as well. When you hear a friend ask for coffee, the details of her order don't just slip away in your mind—your brain must produce a protein that actively destroys the synapses encoding that short-term memory, according to a 2010 paper in Cell. Much psychological research supports the idea that forgetting is essential to memory and emotional health. Tsien's new work, published January 8 in Scientific Reports, suggests that older brains hold on to their connections more dearly—which helps to explain why learning is more laborious as we age and why memory trouble later in life so often involves the accidental recall of outdated information. © 2013 Scientific American

Keyword: Learning & Memory; Development of the Brain
Link ID: 18220 - Posted: 06.03.2013

By JENNA WORTHAM ON a recent family outing, my mother and sister got into a shouting match. But they weren’t mad at each other — they were yelling at the iPhone’s turn-by-turn navigation system. I interrupted to say that the phone didn’t understand — or care — that they were upset. “Honey, we know,” my mom replied. “But it should!” She had a point. After all, computers and technology are becoming only smarter, faster and more intuitive. Artificial intelligence is creeping into our lives at a steady pace. Devices and apps can anticipate what we need, sometimes even before we realize it ourselves. So why shouldn’t they understand our feelings? If emotional reactions were measured, they could be valuable data points for better design and development. Emotional artificial intelligence, also called affective computing, may be on its way. But should it be? After all, we’re already struggling to cope with the always-on nature of the devices in our lives. Yes, those gadgets would be more efficient if they could respond when we are frustrated, bored or too busy to be interrupted, yet they would also be intrusive in ways we can’t even fathom today. It sounds like a science-fiction movie, and in some ways it is. Much of this technology is still in its early stages, but it’s inching closer to reality. Companies like Affectiva, a start-up spun out of the M.I.T. Media Lab, are working on software that trains computers to recognize human emotions based on their facial expressions and physiological responses. A company called Beyond Verbal, which has just raised close to $3 million in venture financing, is working on a software tool that can analyze speech and, based on the tone of a person’s voice, determine whether it indicates qualities like arrogance or annoyance, or both. © 2013 The New York Times Company

Keyword: Emotions; Robotics
Link ID: 18219 - Posted: 06.03.2013

Rebecca J. Rosen What would you draw if somebody told you to draw a neuron? According to a new study, your sketch will depend on how much science education you have, but not in the way you'd expect. In the image above, the top row -- those detailed, labeled, neat renderings -- are the work of undergraduates. The bottom row, with their janky, sparse lines, come from the leaders of neuroscience research laboratories. That martini-glass looking thing over there on the left? That's a neuron, as drawn by a professional scientist. The middle row, some intermediary step, shows drawings from postdocs and graduate students. These drawings come from a new study published in the journal Science Education. Its authors, a team at King's College London led by education professor David Hay, found that nearly every single undergraduate student they studied (all but three of 126) faithfully reproduced textbook-style neurons, something akin to a canonical image from an 1899 book detailing the brain, which, the authors say, "has enjoyed an unusually pervasive influence." These drawings are "typified by a multipolar cell body and truncated, feathery dendritic processes around a clearly demarcated nucleus." Many of the drawings were annotated. For the "trainee scientists" -- those in PhD programs or completing a postdoc -- the neurons appeared more like what would be seen in a microscope image. Nuclei were excluded, the number of dendrites was reduced, and orientation was inconsistent -- all characterizing neurons as you would see them "in nature" not in the pages of a textbook. © 2013 by The Atlantic Monthly Group

Keyword: Brain imaging; Attention
Link ID: 18218 - Posted: 06.03.2013

by Paul Gabrielsen Take a whiff, men. A chemical component of other guys' sweat makes men more cooperative and generous, new research says. The study is the first to show that this pheromone, called androstadienone, influences other men's behavior and reinforces the developing finding that humans are susceptible and responsive to these chemical signals. Pheromones are everywhere in the animal world. Bugs in particular give off these chemicals to sound an alarm, identify a food source, or attract a mate. And smitten animals may indeed have "chemistry" together—pheromone signals are a subconscious part of their communication. Scientists didn't know if humans played that game as well. But in the last 30 years, they've identified both male and female putative pheromones that are linked to mood and reproductive cycles. Some fragrancemakers have even incorporated them into their products, hoping to add an extra emotional punch to colognes and perfumes. Real-life pheromones don't smell so nice, however: The specialized glands that produce these chemical compounds are located near the armpit, where they mix with sweat. Previous investigations focused on the chemicals as sexual attractants—studying a male pheromone's effect on female mood and behavior, for example. Turns out that women aren't the only ones susceptible to the power of male pheromones. Evolutionary biologist Markus Rantala of the University of Turku in Finland crafted an experiment in which 40 men in their mid-20s played a computer game in which two players decided how to share €10. One player offers a possible split, and the other decides whether to accept or reject it. Each participant took a turn making or deciding on offers. © 2010 American Association for the Advancement of Science

Keyword: Chemical Senses (Smell & Taste); Aggression
Link ID: 18217 - Posted: 06.01.2013

Posted by Dr. Claire McCarthy Thumbnail image for sleep.jpgAccording to a study just released, the number of hours kids sleep at night is more affected by genetics than by bedtime or how quiet or dark it is. While daytime naps can be affected and changed by messing with the environment, nighttime sleep is a more wired thing. This doesn’t surprise me at all, actually. For years I’ve been hearing from parents about how much their children sleep, and there is remarkable variation. Some kids sleep a lot at night and a lot during the day too, while others truly barely sleep at all—and yet, for the most part, they seem to get the sleep they need. It’s hard to explain this variation to parents, who understandably think that all kids of a certain age must need roughly the same amount of sleep. That’s just one of the conversations I seem to have again and again about sleep. When I read the study I thought: this would be a great opportunity to write a blog about the things I wish all parents knew about sleep. So here they are: Every child needs a different amount of sleep, as the study points out. It depends on age, to some extent, but it also depends on genetics, what they do during the day and all sorts of factors we don’t understand yet. So instead of counting hours, look at your kid. Are they generally tired or cranky during the day? If so, they may need more sleep. If they are healthy, act rested, have enough energy, get along with others (and are doing okay in school if they go to school), they are probably getting enough sleep. © 2013 NY Times Co.

Keyword: Sleep
Link ID: 18216 - Posted: 06.01.2013