by Bob Holmes Honest people don't have to work at not cheating. They're not even tempted. That's the conclusion of the first-ever neurobiological study of honesty and cheating, which could someday help develop brain-based tests of truthfulness. When studying honesty, neuroscientists usually ask people to either tell the truth or lie while undergoing a brain scan. This is unsatisfactory, because even the "liars" are doing as they were told, so Joshua Greene and Joseph Paxton at Harvard University came up with an alternative. They asked volunteers to bet money on the flip of a coin. Sometimes the players had to record their predictions before the flip, and sometimes they said whether they had guessed correctly after the flip, giving them the opportunity to cheat. Some – but not all – did so, as evidenced by an abnormally high "success" rate. Honesty test? In each round, fMRI was used to record brain activity in the prefrontal cortex and other regions associated with decision making and behavioural control. Honest players showed no increase in brain activity when they had a chance to cheat, suggesting that they didn't have to make a conscious effort to be honest. In contrast, dishonest players showed increased brain activity whenever they had a chance to cheat – even when they reported (presumably truthfully) that they had lost. © Copyright Reed Business Information Ltd.

Keyword: Emotions
Link ID: 13050 - Posted: 06.24.2010

By Susan Cosier Have you ever heard a song when none was playing, clearly seen someone’s face when no one was there or felt the presence of a person, only to turn around to an empty room? If you’ve consumed a lot of caffeine—the equivalent to seven cups of coffee—you are three times more likely to hear voices than if you had kept your caffeine intake to less than a cup of coffee, according to psychologists at the University of Durham in England. Their recent study shows that overingesting the stimulant slightly increases your risk of experiencing other hallucinations as well. Caffeine heightens the physiological effects of stress, lead author Simon Jones says. When someone feels anxiety, the body releases the hormone cortisol, and when people drink plenty of caffeine-infused tea, coffee or soda, their body produces more of the hormone when they encounter stressful events. Researchers have proposed that cortisol may trigger or exaggerate psychotic experiences by increasing the amount of the neurotransmitter dopamine flowing into the brain’s limbic areas, evolutionarily ancient regions involved in emotion, memory and behavior. “The prevalence of hallucinations is probably greater than people would expect,” Jones says. Research shows that every year about 5 to 10 percent of people—many of whom do not suffer from mental illness—experience delusions such as hearing voices and seeing things that are not there. According to Jones, “a range of people have frequent hallucinations yet cope well with these experiences.” © 1996-2009 Scientific American Inc.

Keyword: Schizophrenia; Drug Abuse
Link ID: 13049 - Posted: 06.24.2010

Kate Ravilious Inspired by a blind man who also navigates using sound, a team of Spanish scientists has found evidence that suggests most humans can learn to echolocate. The team also confirmed that the so-called palate click—a sharp click made by depressing the tip of the tongue against the roof of the mouth—is the most effective noise for people to use. Daniel Kish, executive director of World Access for the Blind in Huntington Beach, California, was born blind. He taught himself to "see" using palate clicks when he was a small child. Kish is able to mountain bike, hike in the wilderness, and play ball games without traditional aids. To better understand Kish's skill, Juan Antonio Martínez and his colleagues at the University of Alcalá in Madrid trained ten sighted students to echolocate. "It was very difficult to persuade some people to take part in the experiments, because most [of our] colleagues though that our idea was absurd," Martínez said. The students were asked to close their eyes and make sounds until they could tell whether any objects were nearby. © 1996-2009 National Geographic Society

Keyword: Hearing
Link ID: 13048 - Posted: 06.24.2010

By Gisela Telis There may be more to a cat's purr than meets the ear. A new study reports that our feline friends modify their signature sound when seeking food, adding a higher-frequency element that exploits our sensitivity to infant wails--and thus making it harder to ignore. Although guinea pigs and even elephants can purr, felines get most of the credit for the mysterious sound. The low rumble--at 27 Hz, it's comparable to the lowest note on a piano--serves as a kind of smile, often indicating contentment. It also sometimes crops up when a cat is sick or injured, perhaps to reassure themselves, ask for help, or aid in their own healing. Behavioral ecologist Karen McComb of the University of Sussex in Brighton, U.K., became acquainted with another function for the sound when her cat Pepo began waking her for his early-morning breakfast with an insistent purr. She lamented her loss of sleep to a few cat-owning friends and learned that they too were "purred" into feeding their pets. As an animal communication expert, McComb set out to discover what made these particular purrs so coercive. She recruited 10 cat owners to record their pets' purrs when the cats were clearly seeking food and when they were resting or being petted. Next, McComb and colleagues asked 50 volunteers with varying levels of cat experience to listen to the recorded purrs and rank them according to urgency. Seventy-five percent of the volunteers--including some who had never owned cats--consistently identified the food-demanding, solicitous purrs as more urgent and more unpleasant than nonsolicitous purrs from the same cat. (See if you can hear the difference: normal purr and solicitous purr.) © 2009 American Association for the Advancement of Science

Keyword: Language; Evolution
Link ID: 13047 - Posted: 06.24.2010

Jennifer Viegas, Discovery News -- Dogs possess a two-year-old child's capacity to understand human pointing gestures, with dogs requiring next to zero learning time to figure out the visual communication, according to two recent studies. The comparison with kids doesn't end there. Due to domestication, dogs appear to be predisposed to read other human visual signals, including head-turning and gazing. Pet owners often use baby talk, scientifically known as "motherese," with both children and dogs, allowing canines and kids to receive similar social stimulation. Since chimpanzees and other non-human primates often flunk pointing gesture tests, the studies suggest dogs may understand humans better than even our closest living animal relatives do. "The human pointing gesture is cooperative in its nature," Gabriella Lakatos told Discovery News. Lakatos, a researcher in the Department of Ethology at Eotvos University, led the first study, published in the current issue of Animal Cognition. dog gesture toddler video She explained that other recent studies suggest chimpanzees "might have difficulties with comprehending situations based on cooperation," mentioning "the observation that chimpanzees do not actively share food." Dogs, on the other hand, often eagerly cooperate. © 2009 Discovery Communications, LLC.

Keyword: Language; Evolution
Link ID: 13046 - Posted: 06.24.2010

Matt Walker Common frogs (Rana temporaria) mating For frogs, timing is everything Amphibians around the world synchronise their mating activity by the full moon, researchers have discovered. This global phenomenon has never been noticed before, but frogs, toads and newts all like to mate by moonlight. The animals use the lunar cycle to co-ordinate their gatherings, ensuring that enough males and females come together at the same time. In doing so the creatures maximise their spawning success and reduce their odds of being eaten. Details of the discovery are published in the journal Animal Behaviour. Biologist Rachel Grant of the Open University was studying salamanders near a lake in central Italy for her PhD in 2005 when she noticed toads all over the road, under a full moon. "Although this might have been a coincidence, the following month I went along the same route every day at dusk and found that the numbers of toads on the road increased as the moon waxed, to a peak at full moon, and then declined again," she says. BBC © MMIX

Keyword: Biological Rhythms; Sexual Behavior
Link ID: 13045 - Posted: 06.24.2010

LONDON - Thousands of people with schizophrenia worldwide could have been saved if doctors had prescribed them the anti-psychotic drug clozapine, a new study says. Clozapine was introduced in the 1970s, but was banned for about a decade because of a rare but potentially deadly side effect: up to 2 percent of patients lose their white blood cells while taking the drug. It was brought back to the market in the 1980s with warnings about its use, and is sold generically as Clozaril, Leponex, Denzapine, Fazaclo, among other names. Story continues below ↓advertisement | your ad here In most developed countries, guidelines recommend clozapine only as a last resort, if patients have already tried two other drugs but still aren't better. In a study examining the death rates of about 67,000 schizophrenic patients in Finland versus those of the general population between 1996 and 2006, Jari Tiihonen, of the University of Kuopio in Finland, and colleagues found that patients on clozapine had the lowest risk of dying, compared to other patients with schizophrenia. The study was published online Monday in the medical journal, Lancet. James MacCabe, a consultant psychiatrist at the National Psychosis Unit at South London and Maudsley Hospital, called the research "striking and shocking." He was not linked to the study. "There is now a case to be made for revising the guidelines to make clozapine available to a much larger proportion of patients," he said. Copyright 2009 The Associated Press.

Keyword: Schizophrenia
Link ID: 13044 - Posted: 07.13.2009

by Peter Fraser ANIMAL welfare legislation generally applies only to vertebrates. There are, however, moves to include invertebrates. Proposed changes to European law, for example, would extend welfare laws to crabs and lobsters. Up to now the only invertebrate protected is the common octopus. "Invertebrate rights" has become a campaigning issue. Advocates for Animals recently produced a report which concludes that there is "potential for experiencing pain and suffering" in crustaceans. The group is particularly concerned about boiling lobsters alive. The wider public is also showing interest. Research supposedly demonstrating that hermit crabs feel and remember pain received worldwide news coverage (Animal Behaviour, vol 77, p 1243). I find the evidence unconvincing. One key argument put forward for protecting crustaceans hinges on similarities between their nervous systems and our own. Such similarities are taken as prima facie evidence that mammals feel pain. Surely this applies to invertebrates too? It is true that crustaceans have neural systems similar in some respects to those involved in human pain, but there are also important differences. The brains of lobsters and crabs have only 100,000 neurons compared with 100 billion in mammals. Their nerves conduct signals 100 times more slowly, and their brains lack the higher centres necessary for a mammal to suffer pain. © Copyright Reed Business Information Ltd.

Keyword: Animal Rights
Link ID: 13043 - Posted: 06.24.2010

By Frederik Joelving Bad language could be good for you, a new study shows. For the first time, psychologists have found that swearing may serve an important function in relieving pain. The study, published today in the journal NeuroReport, measured how long college students could keep their hands immersed in cold water. During the chilly exercise, they could repeat an expletive of their choice or chant a neutral word. When swearing, the 67 student volunteers reported less pain and on average endured about 40 seconds longer. Although cursing is notoriously decried in the public debate, researchers are now beginning to question the idea that the phenomenon is all bad. "Swearing is such a common response to pain that there has to be an underlying reason why we do it," says psychologist Richard Stephens of Keele University in England, who led the study. And indeed, the findings point to one possible benefit: "I would advise people, if they hurt themselves, to swear," he adds. How swearing achieves its physical effects is unclear, but the researchers speculate that brain circuitry linked to emotion is involved. Earlier studies have shown that unlike normal language, which relies on the outer few millimeters in the left hemisphere of the brain, expletives hinge on evolutionarily ancient structures buried deep inside the right half. © 1996-2009 Scientific American Inc.

Keyword: Emotions; Language
Link ID: 13042 - Posted: 06.24.2010

By CHARLES SIEBERT On the afternoon of Sept. 25, 2002, a group of marine biologists vacationing on Isla San José, in Baja California Sur, Mexico, came upon a couple of whales stranded along the beach. A quick assessment indicated that they had died quite recently. The scientists radioed a passing vessel and sent a message to a colleague at a nearby marine-mammal laboratory, who came to the beach to do an examination. They were beaked whales, of which there are 20 known species. Relatively small members of the cetacean family, they resemble outsize dolphins, and because of their deep-diving ways, they are among the least observed and understood. Curiously, the stranding on Isla San José followed by just one day the stranding of at least 14 other beaked whales 5,700 miles away along the Canary Islands beaches of Lanzarote and Fuerteventura. Rescuers there worked feverishly to water down the whales and keep them cool. They all eventually died, however, and some of their bodies were immediately sent to the nearby city Las Palmas de Gran Canaria for analysis. It is nearly impossible to pinpoint the precise cause of a whale’s stranding. Theories invariably include factors like the straying of a sick and dying whale leader, faithfully followed by the members of his pod, or sudden shallows along the shores of a migratory route. The two strandings in September 2002, however, did have something intriguing in common. It was noted by the Canary Islands rescuers that naval vessels were carrying out exercises that day not far offshore, a situation that had accompanied four other mass whale strandings on Canary Islands beaches since 1985. And while no such military exercises were being conducted off the beaches of Isla San José, the vessel that the scientists radioed turned out to be a research ship dragging an array of powerful underwater air guns that were repeatedly set off the previous morning in the course of seismic tests of the region’s ocean floor. Copyright 2009 The New York Times Company

Keyword: Hearing; Intelligence
Link ID: 13041 - Posted: 06.24.2010

Scientists have discovered a protein molecule on the surface of nerve cells that makes people cough when irritated. They hope the findings could lead to new drugs to treat chronic cough, which affects about 10% of the UK population. Coughing is the symptom for which medical advice is most commonly sought and it accounts for more than half of new patient consultations to a GP. The University of Hull study was presented to a British Pharmacological Society meeting. Lead researcher Professor Alyn Morice said: "Chronic cough can be socially isolating and disabling and people come from all over Europe to my cough clinic because the cough is ruining their lives, yet current treatment options are limited with remedies little better than honey and lemon." Research has already focused on protein receptors which sit on the surface of nerve cells, and enable them to pass on signals. One particular receptor - TRPV1 - generated excitement after it was shown to produce a cough reflex when stimulated by capsaicin, an extract of chilli peppers. A number of companies produced potential drugs to block the receptor, which helps the body to sense heat, and to register pain. However, their work was stymied by the revelation that patients in which the receptor was blocked not only had an impaired ability to detect heat, but also developed a higher body temperature. The Hull group instead focused on a different type of receptor, called TRPA1, which is more concerned with the ability to sense coldness. They showed it produced a cough reflex when it was stimulated by a cinnamon extract. They went on to clone the receptor in order to study its chemistry more closely. (C)BBC

Keyword: Pain & Touch
Link ID: 13040 - Posted: 07.11.2009

NEW YORK - Teenagers who drink heavily are also more likely than their peers to have behavioral problems or symptoms of depression and anxiety, a new study finds. The study, of nearly 9,000 Norwegian teenagers, found that those who said they had been drunk more than 10 times in their lives were more likely to have attention and conduct problems in school. Meanwhile, heavy-drinking girls showed higher rates of depression and anxiety symptoms. The findings, published in the online journal Child and Adolescent Psychiatry and Mental Health, are based on a one-time survey. They do not, therefore, show whether the drinking came before or after the teenagers' other problems. Story continues below ↓advertisement | your ad here "We can say that mental health problems (are) closely connected to alcohol drinking and intoxication, but we cannot from these data say anything about which comes first," explained lead researcher Dr. Arve Strandheim, of the Norwegian University of Science and Technology in Trondheim. That said, conduct and attention problems do tend to develop early in childhood, and would be less likely to arise in adolescence, Strandheim told Reuters Health. But regardless of whether drinking problems or other issues come first, the bottom line is that parents should be aware that they often go hand-in-hand, according to the researcher. Copyright 2009 Reuters.

Keyword: Depression; Drug Abuse
Link ID: 13039 - Posted: 06.24.2010

by Nic Fleming AS GENERATIONS of men with two left feet have learned to their cost, having the dance floor prowess of Mr Bean is no help in the mating game. To make matters worse for the terminally uncoordinated, it now looks as if women are right to go for men who can strut their stuff like John Travolta or Patrick Swayze - as they are more likely to be strong and to produce healthy offspring. Nadine Hugill and Bernhard Fink of the University of Göttingen in Germany found that men whose dancing was rated as attractive and assertive by women were physically stronger than those whose moves were dismissed as below par. "We already know women use static cues such as facial and bodily characteristicsMovie Camera in their assessments of men," says Fink. "This study shows that dynamic cues such as dancing ability might also be used to assess male quality in terms of strength and dominance - traits which eventually signal status." The researchers recorded video clips of 40 heterosexual male students dancing to the drum track of the Robbie Williams song Let Me Entertain You. Participants wore white overalls, and a blurring filter was used to disguise information about their clothing, as well as face and body shape. Hand grip strength was measured using a dynamometer. Twenty-five female students viewed the muted videos and rated the attractiveness of the dancers, while another 25 rated their assertiveness. Even after controlling for body weight, there were strong correlations between strength scores and both perceived attractiveness and assertiveness. © Copyright Reed Business Information Ltd

Keyword: Sexual Behavior; Evolution
Link ID: 13038 - Posted: 06.24.2010

By Emily Anthes We take it for granted that certain aspects of our social behavior—whether we chat easily with strangers at a party, for instance, or prefer to be a wallflower—are influenced by genetics. But now researchers at the University of California, San Diego, and Harvard University have shown that genes have a much broader sway, affecting the kinds of social networks people form and the positions they occupy in them. James Fowler, a political scientist at U.C.S.D., and his colleagues studied the social networks of 1,110 adolescent fraternal and identical twins. They found that three aspects of the twins’ social networks appeared to be shaped by genetics. How many times each teen was named by others as a friend and how likely each youth’s friends were to know one another were both approximately 50 percent related to genetic factors. Whether a teen was located at the center of a network or toward the edge was about 30 percent genetic. “We have innate characteristics that give us a tendency to gravitate toward one part of a network,” Fowler explains. “We vary in the tendency with which we’ll attract people as friends, and we vary in our tendency to introduce our friends to one another.” The genetic foundation uncovered in the study, he posits, is probably a broad combination of genes that are mostly linked to personality traits such as humor, generosity or extroversion. © 1996-2009 Scientific American Inc.

Keyword: Genes & Behavior
Link ID: 13037 - Posted: 06.24.2010

Tatiana Falcone, MD, Erin Carlton, MS, Kathleen Franco, MD, and Damir Janigro, PhD When the solution to a clinical or scientific puzzle eludes us for more than a century, as with schizophrenia, we need new methods to examine the pathology. If we want to make an impact on the disease we must shift research paradigms and focus on the early detection, early intervention, and new avenues of treatment that address different symptoms of schizophrenia. Immunological and blood-brain barrier (BBB) abnormalities in patients with psychosis have been repeatedly noted. Hundreds of studies of schizophrenic illness in adults have documented immunological abnormalities in these patients, and an increasing number of studies have shown a link between S100b, a marker of BBB function, and schizophrenic illness (Table).1-3 In looking at the possible causes of schizophrenia, earlier studies focused on neurons. Increasing evidence now suggests that the glia, cerebral vasculature, and the BBB may be involved. Two postmortem studies reported activated glial cells in a subgroup of patients with schizophrenia.4,5 Using the marker PK11195 to label glial cells in patients with psychosis, Hirsch6 found activation throughout the cortex using positron emission tomographic accentuation in the frontal lobes. Here we present evidence linking inflammation, immunological abnormalities, BBB disruption, and neurological disorders. The BBB is a physical and metabolic barrier that regulates and protects the brain. This barrier is composed of tight junctions between endothelial cells in CNS vessels that restrict the passage of solutes. Several lines of evidence have pointed to a link between CNS problems—such as psychiatric disorders and inflammation—that occur in response to pathogens. Impairment of the BBB may be the consequence of immunopathogenic mechanisms.7 © 1996 - 2009 CMPMedica LLC

Keyword: Schizophrenia; Neuroimmunology
Link ID: 13036 - Posted: 06.24.2010

People with superior language skills early in life may be less likely to develop Alzheimer's disease decades later, research suggests. A team from Johns Hopkins University studied the brains of 38 Catholic nuns after death. They found those with good language skills early in life were less likely to have memory problems - even if their brains showed signs of dementia damage. The study appears online in the journal Neurology. Dementia is linked to the formation of protein plaques and nerve cell tangles in the brain. But scientists remain puzzled about why these signs of damage produce dementia symptoms in some people, but not others. The researchers focused on nuns who were part of an ongoing clinical study. They divided the women into those with memory problems and signs of dementia damage in the brain, and those whose memory was unaffected regardless of whether or not they showed signs of dementia damage. And they also analysed essays that 14 of the women wrote as they entered the convent in their late teens or early 20s, assessing them for complexity of language and grammar. The study showed that language scores were 20% higher in women without memory problems than those with signs of a malfunctioning memory. The grammar score did not show any difference between the two groups. Lead researcher Dr Juan Troncoso said: "Despite the small number of participants in this portion of the study, the finding is a fascinating one. Our results show that an intellectual ability test in the early 20s may predict the likelihood of remaining cognitively normal five or six decades later, even in the presence of a large amount of Alzheimer's disease pathology." (C)BBC

Keyword: Alzheimers; Language
Link ID: 13035 - Posted: 07.09.2009

By Linda Carroll If you listen to popular songs, you might conclude there’s no day as depressing as a Monday. But a new study shows that lyricists may have gotten it all wrong and that Wednesday is really the darkest day of the week. The study, published in Social Psychiatry and Psychiatric Epidemiology, found that people are far more likely to kill themselves in the middle of the week than in the beginning or the end: almost 25 percent of suicides occur on Wednesdays as compared to 14 percent on Mondays or Saturdays, the two days tied for second-highest suicide rates. The study also found if you make it through Wednesday, your risk for suicide plummets by more than half the following day; Thursdays have the lowest rate, with only 11 percent of suicides. Research up until now has pointed a finger at Mondays, said the new report’s lead author, Augustine J. Kposowa, a professor of sociology at the University of California, Riverside. “Everyone talks about the Monday blues,” Kposowa added. “But if you look at more recent data, it looks like things have shifted and now it’s the middle of the week that’s the problem.” More study is needed to fully understand the findings, but researchers suspect that we may be seeing a positive impact of technology on suicide and depression. With the advent of e-mail, Internet discussion groups and text messaging, people can now stay in touch with the outside world even if they are holed up by themselves at home the entire weekend. © 2009 msnbc.com.

Keyword: Depression
Link ID: 13034 - Posted: 06.24.2010

By JOHN BRANCH SEDALIA, Colo. — In the middle of the night, Diane Van Deren will leave her house against the foothills of the Rocky Mountains. She will cut west through the dark canyons with her running shoes and a headlamp, but without a kiwi-sized part of her right temporal lobe. She used to run away from epileptic seizures. Since brain surgery, she just runs, uninhibited by the drudgery of time and distance, undeterred by an inability to remember exactly where she is going or how to get back. “It used to be, call for help if Mom’s not back in five hours,” Van Deren said. She laughed. “That rule has been stretched. I’ve got a 24-hour window now. Isn’t that sad?” Van Deren, 49, had a lobectomy in 1997. She has become one of the world’s great ultra-runners, competing in races of attrition measuring 100 miles or more. She won last year’s Yukon Arctic Ultra 300, a trek against frigid cold, deep snow and loneliness, and was the first woman to complete the 430-mile version this year. This weekend she will run in the Hardrock 100 in Silverton, Colo. It has a total elevation gain of 33,000 feet and crosses the top of 14,048-foot Handies Peak. About 150 people will enter. About half will not finish the 100 miles within the allotted 48 hours. Copyright 2009 The New York Times Company

Keyword: Epilepsy; Learning & Memory
Link ID: 13033 - Posted: 06.24.2010

By Mary Bates A great deal of scientific research is driven by a very fundamental question: What makes us human? And what are the properties of the human brain that make these talents possible? One challenge facing scientists is that answering these questions often requires the use of nonhuman animals as subjects. In fact, animal models have even proved essential when it comes to studying uniquely human talents, such as language. In 2001 Cecilia S. L. Lai and colleagues at the University of Oxford identified FOXP2 as the first gene specifically involved in speech and language development in humans. The gene was discovered when researchers began studying members of a family that exhibited severe language deficits: they struggled to speak in grammatically correct sentences and often failed to comprehend the language of others, although they demonstrated no other cognitive handicaps. A genetic analysis of the family linked these severe linguistic deficits to a mutation in the FOXP2 gene. Interestingly, the FOXP2 gene is highly conserved among vertebrates, including humans, songbirds, bats and rodents, perhaps indicating a shared function. Experimental evidence from a variety of animals suggests a general role in communication for FOXP2. For instance, mice that lack the gene produce abnormal ultrasonic vocalizations, while the expression of the gene changes in the brains of songbirds during vocal learning. Mice have been especially useful models in elucidating the role of FOXP2 in communication and fine motor development. While this might seem paradoxical (rodents don’t talk, so how can they teach us about speech?) mice have several important advantages. © 1996-2009 Scientific American Inc.

Keyword: Language; Hearing
Link ID: 13032 - Posted: 06.24.2010

by Catherine Brahic Primates can intuitively recognise some rules of grammar, according to a study of cotton-topped tamarin monkeys (Saguinus oedipus). The findings do not mean primates can communicate using language, but they do suggest that some of the skills required to use language may be linked to very basic memory functions. One grammatical structure that is found across many languages is affixation: the addition of syllables, either at the beginning or at the end of a word, to modify its meaning. For instance, in English, the suffix "–ed" is added to verbs to make the past tense. In German, the same effect is achieved by adding the prefix "ge–" to the front of verb stems. Ansgar Endress and colleagues at Harvard University thought that, because this structure is found in so many languages, it might be linked to basic memory functions that are independent of language. If they could prove this was true, it would suggest ways that children might be learning grammatical structures. To test this, Endress and colleagues studied 14 cotton-top tamarins, which, like all other non-human primates, do not use language to communicate. © Copyright Reed Business Information Ltd.

Keyword: Language; Evolution
Link ID: 13031 - Posted: 06.24.2010