STEAMBOAT SPRINGS, Colorado – As animal models go, the vole isn't near the top of the list. In fact, it wasn't even on the list until relatively recently. Not to be confused with the mole, a much smaller and scientifically less-interesting rodent, voles are about the size of hamsters, but more squat. Nevertheless, along with their cousins the mouse and rat, voles have quickly become an invaluable animal model for social behavior and have helped open up the field of study to very complex issues including romance and even more recently, autism. Larry Young, professor of psychiatry at Emory University, began studying the vole in the mid-1990s "unrelated to autism, just for their unusual behavior. Prairie voles are monogamous and form life-long social attachments, while montane and meadow voles are promiscuous breeders and don't form social attachments at all," Young says. Soon, "using comparative molecular approaches, I began to investigate the molecular mechanisms underlying the species behavior differences. Now, by gaining an understanding of the mechanisms underlying social attachment, we hope to gain insight in human disorders characterized with social impairments, such as autism." But to paraphrase Michael Douglas in the "American President": "Autism isn't easy." Young says there are two specific problems in studying autism. First, "there aren't any animal models of autism. Animals just don't get autism. Second, autism is itself a disrupted social phenotype with a broad spectrum of interrelated disorders" that is almost uniquely variable in each individual patient.

Keyword: Autism; Hormones & Behavior
Link ID: 7653 - Posted: 06.24.2010

Scientists say they have discovered a gene linked to diabetes and obesity, offering hope for a diagnostic test. Faulty versions of the gene ENPP1 disrupt the way the body stores energy and handles sugar by blocking the hormone insulin. Children with faulty versions were obese at as young as five years old. The Imperial College London team told Nature Genetics that spotting the problem early and intervening could save lives. Experts have already predicted that the UK is facing an obesity and diabetes time bomb, with rates soaring among children and adults alike. The number of people in the UK with diabetes is predicted to reach three million by 2010. Diabetes and obesity increase the likelihood of potentially fatal diseases such as heart attacks. While inactivity and poor diets are much to blame for obesity and the metabolic problems that can lead to full-blown diabetes, the authors of the latest study say some people are genetically prone as well. In these individuals - up to 20% of Caucasians and 50% of black communities - leading a healthier lifestyle from the outset is imperative if they are to avoid problems in later life, say Dr Philippe Froguel and his team. They looked at French families with a strong history of diabetes and obesity and compared them with families that did not. When they compared the genes of 1,225 children who were grossly obese or overweight at ages five and 11 with 1,205 normal weight children they found an obvious pattern - many of the obese children possessed culprit versions of ENPP1. (C)BBC

Keyword: Obesity; Genes & Behavior
Link ID: 7652 - Posted: 07.18.2005

STEAMBOAT SPRINGS, Colorado – Maternal aggressive/protective behavior is recognized throughout mammalian species, especially during lactation. When hiking, we warn our kids not to approach bear cubs, or to get between a cub and the mother. While driving and you see a fawn, you know a doe can't be too far away and will run headlong to protect it. The same neurohypophyseal (NH) hormone, oxytocin (OT), is responsible for both the physiological and behavioral changes, but the site of action is quite different. OT is released during parturition and in lactation not only from NH terminals into the bloodstream in order to support reproductive systems, but also within the brain, into the supraoptic nucleus (SON) and paraventricular nucleus (PVN), where it has marked behavioral impact. OT release in the brain is involved with such reproductive events as "morphological plasticity, autoregulation of OT neuronal activity and promotion of maternal behavior, including maternal aggressive behavior to protect offspring," Inga D. Neumann of the University of Regensburg, Germany, notes. "Thus in lactating rats from a line bred for high-anxiety behavior, or HAB, OT release within both the central amygdala and the PVN was positively correlated with the level of maternal offensive behavior against an intruder." In addition, the lactating HAB dams display higher aggression and central OT release compared with a low-anxiety line.

Keyword: Aggression; Hormones & Behavior
Link ID: 7651 - Posted: 06.24.2010

Hypnosis brings to mind thoughts of swinging watches and some stage hypnotist making people walk around acting like chickens, but how much can it really change the way we think and act? Hypnotic suggestion seems to be able to put novel ideas into our heads, making us do and say unusual things. But some psychologists believe it is powerful enough to override some of the most ingrained and automatic processes of the brain, such as reading. Reading is a skill that once learned becomes unconscious and automatic. Even so, brain researcher Amir Raz has shown that a form of hypnotic suggestion can make some people undo automatic behaviors, even to the point of viewing their native language as meaningless. "It tells us a little bit about what we can and cannot do to certain deeply ingrained processes," says Raz from the New York State Psychiatric Institute. "In a way, this is very much like 'unringing' the bell if you're thinking about Pavlov and his dogs. Pavlov would ring a bell and the dogs would salivate because Pavlov would condition them to give them food right after the bell was rung," Raz explains. "What we're doing here is we're taking a process that is already deeply ingrained in people, reading, in this case. When we start reading this process is not at all automatic but after a few years of training, particularly when we're adults and particularly as readers, we read effortlessly. As soon as something is in front of us, we read it immediately. What I'm showing is that you can actually make people unlearn the reading process." © ScienCentral, 2000-2005.

Keyword: Language
Link ID: 7650 - Posted: 06.24.2010

Intelligence may lead to a better paid job and quality of life but, in old age, cleverness has no effect on happiness, new research suggests. A happy old age is what many people spend their lives preparing for, aiming for financial security and good health in their dotage. But one thing people need not worry about, it seems, is how clever they are. A study of more than 400 pensioners reveals that cognitive ability is unrelated to happiness in old age. The Scottish research looked at a group of 416 people born in 1921, who underwent intelligence tests at the ages of 11 and 79. At the age of 80, the group was also sent a “satisfaction with life” questionnaire, which had them assess their current level of happiness. “We found no association between levels of mental ability and reported happiness, which is quite surprising because intelligence is highly valued in our society,” says Alan Gow, who carried out the research with colleagues at the University of Edinburgh, UK. Participants were asked to respond to five statements about their happiness and give a rating on a scale of 1 to 7 according to how strongly they agreed. The statements referred mainly to their current life, but also asked if, given the chance, they would like to have done anything differently with their lives. © Copyright Reed Business Information Ltd.

Keyword: Intelligence; Emotions
Link ID: 7649 - Posted: 06.24.2010

By NICHOLAS WADE If stem cells ever show promise in treating diseases of the human brain, any potential therapy would need to be tested in animals. But putting human brain stem cells into monkeys or apes could raise awkward ethical dilemmas, like the possibility of generating a humanlike mind in a chimpanzee's body. No such experiments are planned right now. But in a paper today in the journal Science, a group of scientists and ethicists is advising researchers to exercise care with such experiments, particularly if they should lead to a large fraction of a chimpanzee's brain's being composed of human neurons. The group, led by Ruth R. Faden, a biomedical ethicist at Johns Hopkins University, acknowledged the view that monkeys and apes should not be experimented on at all, but nevertheless considered what kinds of research should be permitted if the experiments were required by regulatory authorities. Clinical trials often depend on previous tests with rats or mice that have some equivalent of the human disease. But for some diseases that affect the human brain, the rodent models may not serve so well. If stem cell therapies for Alzheimer's or Parkinson's disease were to be developed, the Food and Drug Administration might require tests in monkeys or apes before permitting clinical trials. Copyright 2005 The New York Times Company

Keyword: Stem Cells
Link ID: 7648 - Posted: 07.15.2005

Writing in the journal Nature, Michael Kosfeld and colleagues reported that intranasal administration of oxytocin, a human neuropeptide involved in maternal bonding, “causes a substantial increase in trusting behavior, thereby greatly increasing the benefits from social interactions.”1 The double-blind study involved a trust game with real monetary stakes, in which the subjects played the role of either an investor or a trustee. Investors could choose whether and how much money to invest with an anonymous trustee, and the trustees could choose whether to honor or violate the investors’ trust. The investors who had inhaled the oxytocin invested 17% more money than those who received the placebo. In what is becoming an increasingly tantalizing form of neuroscience, researchers in this study obtained consent not to study the phenomenon about which they were interested, trust, but rather the effect of a hormone more generally. The seemingly subtle shift in language, with its attendant deception, was obviously necessary for the researchers to conduct their study. But did they, and do researchers who would study phenomena of character more generally, have a special responsibility to inform subjects about the risks of “shifts in subject consciousness?” It is more than a question of informed consent that is at hand. For just as there is an obvious irony in manipulating subjects’ inclination to trust in order to study the biochemical basis of that trust, there is a broader safety—and indeed human—concern about whether trust should be scientifically manipulated in clinical studies in this way at all.

Keyword: Hormones & Behavior
Link ID: 7647 - Posted: 06.24.2010

By Ceci Connolly A government Web site intended to help parents and teenagers make "smart choices about their health and future" includes inaccurate or misleading information that may alienate some families or prompt riskier behavior, according to a team of medical experts who reviewed the material. Three physicians and a child psychologist analyzed the Bush administration's 4Parents.gov Web site and concluded it made many incorrect assertions about condoms, sexual orientation, single-parent households and the dangers of oral sex. They also found omissions of information that could go a long way toward raising healthy young adults, such as warning against the dangers of drinking alcohol. Rep. Henry A. Waxman (D-Calif.), a frequent administration critic who solicited the analyses, said the site is the latest example of "the distortion of scientific information" in favor of a conservative ideology focused predominantly on promoting abstinence-until-marriage programs. "A federally-funded website should present the facts as they are, not as you might wish them to be," Waxman wrote to Health and Human Services Secretary Mike Leavitt. "It is wrong -- and ultimately self-defeating -- to sacrifice scientific accuracy in an effort to frighten teens and their parents." © 2005 The Washington Post Company

Keyword: Sexual Behavior; Drug Abuse
Link ID: 7646 - Posted: 06.24.2010

By Jennifer Viegas, Discovery News — Chickens do not just live in the present, but can anticipate the future and demonstrate self-control, something previously attributed only to humans and other primates, according to a recent study. The finding suggests that domestic fowl, Gallus gallus domesticus, are intelligent creatures that might worry. "An animal with no awareness of 'later' may not be able to predict the end of an unpleasant experience, such as pain, rendering it (the pain) all-encompassing," said Siobhan Abeyesinghe, lead author of the study. "On the other hand, an animal that can anticipate an event might benefit from cues to aid prediction, but may also be capable of expectations rendering it vulnerable to thwarting, frustration and pre-emptive anxiety." She added, "The types of mental ability the animal possesses therefore dictate how they should best be managed and what we might be able to do to minimize psychological stress." Abeyesinghe, a member of the Biophysics Group at Silsoe Research Institute in England, and her colleagues tested hens with colored buttons. When the birds pecked on one of the buttons, they received a food reward. If the chicken waited two to three seconds, it received a small amount of food. If the bird held out for 22 seconds, it received a "jackpot" that paid out with much more to eat. Copyright © 2005 Discovery Communications Inc.

Keyword: Learning & Memory
Link ID: 7645 - Posted: 06.24.2010

Roxanne Khamsi Mice with memory loss have had their condition reversed, a discovery that should help refine the search for a cure for Alzheimer's disease and other dementias. The study also helps clarify the actual cause of dementia, which should give more focus to drug studies. The brains of people with Alzheimer's and some 50 other forms of dementia are known to have certain characteristic features, including messy bundles of fibres in nerve cells called neurofibrillary tangles. But no one has been sure whether the tangles are a cause or symptom of dementia. Mice engineered to massively overproduce a protein called tau tend to grow more of the tangles and display the same problems with memory and learning as humans with dementia. Researchers think that it is a certain version of the tau protein, rather than a simple over-abundance, that leads to the tangles. It has been speculated that these tau proteins, rather than the tangles, kill nerve cells. Karen Ashe, a neurobiologist at the University of Minnesota Medical School in Minneapolis, and her colleagues hoped to untangle this mystery. They trained mice to navigate a maze partly submerged in water, and watched for signs of memory loss. By the age of three months, mice genetically engineered to express 13 times too much tau protein couldn't remember the route to dry land, and had developed tangles in their brains. ©2005 Nature Publishing Group

Keyword: Alzheimers
Link ID: 7644 - Posted: 06.24.2010

A new type of ear-shape analysis could see ear biometrics surpass face recognition as a way of automatically identifying people, claim the UK researchers developing the system. The technique could be used to identify people from CCTV footage, or incorporated into cellphones to identify the user, says Mark Nixon, a biometrics expert at the University of Southampton. Ears are remarkably consistent, he says. Unlike faces, they do not change shape with different expressions or age, and remain fixed in the middle of the side of the head against a predictable background. “Hair is a problem,” Nixon admits. “But that might be solved by using infrared images.” In an initial small-scale study involving 63 subjects – all taken from a database of face profiles – Nixon and his colleague David Hurley found their method to be 99.2% accurate. This is a great starting point, says Nixon, but in theory the method could be greatly improved. “There are more fixed features available in an ear than we have been measuring,” he says. Much larger populations are needed to determine how reliably it could be implemented. But an initial analysis of the decidability index – a measure of how similar or dissimilar each of the ears were – indicates how unique an individual ear might be. © Copyright Reed Business Information Ltd

Keyword: Hearing
Link ID: 7643 - Posted: 06.24.2010

Researchers have constructed a new detailed map of the three-dimensional terrain of a synapse — the junction between neurons which are critical for communication in the brain and nervous system. The “nano-map,” which shows the tiny spines and valleys resolved at nanometer scale, or one-billionth of a meter, has already proven its worth in changing scientists' views of the synaptic landscape. Using the map as a guide, the research team, led by Howard Hughes Medical Institute investigator Terrence Sejnowski, has developed a biologically accurate computer simulation of synaptic function. The simulation combines 3-D electron microscope maps with computer simulation and physiological measurements from real neurons. Their in silico modeling indicates that the synapse may behave more like a shotgun than a rifle when it comes to firing the neurotransmitters involved in neuronal communication. The textbook view of the synapse describes it as a place where rifle-like volleys of neurotransmitter are launched from one defined region of the sending neuron to another defined target on the receiving neuron. In contrast, the new data suggest that synapse can act like a shotgun, firing buckshot-like bursts of neurotransmitter to reach receptors arrayed beyond the known receiving sites. The researchers say that right now they have little idea of how the synaptic shotgun functions. The research was published in the July 15, 2005, issue of the journal Science. Sejnowski, who is at The Salk Institute, and colleagues Darwin Berg and Mark Ellisman, both of the University of California, San Diego, led the research team, which also included co-authors from Carnegie Mellon University and the University of Pittsburgh. © 2005 Howard Hughes Medical Institute

Keyword: Development of the Brain; Learning & Memory
Link ID: 7642 - Posted: 06.24.2010

Howard Hughes Medical Institute researchers have discovered a novel way in which the brain size of developing mammals may be regulated. They have identified a signaling pathway that controls the orientation in which dividing neural progenitor cells are cleaved during development. The way these cells are sliced during development is critical because at later stages of neurogenesis, vertical cleavage gives rise to two mature neurons that are incapable of further division, while horizontal cleavage yields one neuron and one progenitor cell that can continue to support brain growth. The researchers speculate that this type of regulatory decision point may play a powerful role in determining the ultimate size of the mammalian brain. Inherited disorders that cause the brain to develop too small or too large may also influence this developmental pathway. Howard Hughes Medical Institute investigator Li-Huei Tsai and postdoctoral fellow Kamon Sanada, both at Harvard Medical School, published their findings in the July 15, 2005, issue of the journal Cell. The researchers drew on studies by other researchers that showed that the orientation of cleavage planes in dividing neural progenitor cells in the neocortex determines the fate of the resulting daughter cells. However, nothing was known about the molecular signaling mechanism that regulates the decision to cleave one way or another, said Tsai. © 2005 Howard Hughes Medical Institute.

Keyword: Development of the Brain
Link ID: 7641 - Posted: 06.24.2010

Healthy people, including children, might one day take drugs to boost their intelligence, scientists predict. The think-tank Foresight, outlined the scenario in an independent report looking at potential developments over the next 20 years. Such "cognitive enhancers" could become as "common as coffee", they suggest. Scientists did not rule out children taking exams facing drug tests, as sportsmen do, to see if any have taken 'performance enhancing substances'. The report was compiled by 50 experts, who set out their predictions for the next two decades. Some drugs are already known to aid mental performance. Ritalin, now prescribed to children with attention deficit hyperactivity disorder (ADHD), has already been used by some students to improve their performance in exams. Modafinil, used now to treat sleep disorders, has been shown to help people remember numbers more effectively. It can also make people think more carefully before making decisions. There is also a type of molecule called ampakins, which enhance the way some chemical receptors in the brain work, suggesting drugs could be developed to improve people's memory when they are tired. (C)BBC

Keyword: Attention; Learning & Memory
Link ID: 7640 - Posted: 07.14.2005

By Marc Kaufman Less than six months after it came onto the market, the powerful narcotic painkiller Palladone was abruptly withdrawn yesterday because of evidence that the one-a-day pills could be fatal to patients who take them with alcohol. The Food and Drug Administration asked Purdue Pharma L.P. to stop selling the drug Tuesday and the company complied yesterday, said James Heins, a Purdue spokesman. The 24-hour extended-release medication, the first of its kind in the United States, was approved by the FDA last September for people in chronic pain who were already using morphine-based painkillers. The agency said the withdrawal was triggered by a company study that showed potentially serious or even fatal consequences if a person abusing the drug also drank alcohol. Neither the company nor the FDA reported any instances of the problem among the 11,500 people who have been prescribed the drug. "All powerful pain-management drugs have serious risks if used incorrectly, but the current formulation of Palladone presents an unacceptably high level of patient risk," said Steven Galson, acting director of the FDA's Center for Drug Evaluation and Research. © 2005 The Washington Post Company

Keyword: Pain & Touch; Drug Abuse
Link ID: 7639 - Posted: 06.24.2010

Scientists at New York University School of Medicine reveal the important role of early experience in shaping neuronal development and brain plasticity in a new study published in the July 14 issue of the journal Nature. In mice, the researchers found that sensory deprivation prevented the substantial loss of synapses that typically occurs in growing animals. The effects were most pronounced in the period from young adolescence to adulthood. Synapses are the gaps between neurons through which information travels. Wen-Biao Gan, Ph.D., Assistant Professor of Physiology and Neuroscience, and his colleagues captured images of brain plasticity--its ability to adapt quickly to ever-changing circumstances--and have started to unravel how this dynamic unfolds. The scientists were able to deliver visible evidence of the effect of sensory deprivation. It is well known that a growing child learns many skills. "What is less known," says Dr. Gan, "is that during childhood until puberty in the human brain, as well as in the monkey and mouse, you see a substantial loss of neuronal connections." In learning, it appears the brain needs to lose as it gains. He believes this loss may well be the fundamental process underlying the development and plasticity of the brain. After birth, the number of synapses increases and then decreases sharply. From early childhood to adolescence the synaptic loss could be as much as 50 percent.

Keyword: Development of the Brain
Link ID: 7638 - Posted: 07.14.2005

Being a new mother is exhausting, but if you're a dolphin or a killer whale, you won't be getting any extra sleep-time to recover, in fact you won't be getting any sleep at all. Scientists in California and Russia have discovered that both dolphin and killer whale mothers and calves apparently go with no sleep for the first few months of the new baby's life. "These marine [animals], who are mammals like us, thrive without any extended periods of sleep for over a month," says lead researcher and neuroscientist at UCLA's Sepulveda VA Ambulatory Care Center Jerome Siegel. Siegel and his colleagues monitored two killer whale and calf pairs at SeaWorld San Diego, as well as four dolphin and calf pairs at the Gelendgick Dophinarium near Russia's Black Sea coast. They reported in the journal Nature that during the first postpartum month these animals were awake "24 hours a day," but gradually increased the amount of time they spent sleeping as the calf aged. Siegel says the sleep patterns he and his colleagues observed in the babies are "just the reverse" of all other mammals, which normally sleep the most after birth and gradually taper down to adult levels as they age. "This is a challenge for the idea that sleep is necessary for brain and body growth, because during this period of very rapid development in killer whales, and we've also seen it in dolphins," says Siegel, "There's actually the lowest level of sleep behavior of the animals' entire life." © ScienCentral, 2000-2005.

Keyword: Sleep
Link ID: 7637 - Posted: 06.24.2010

New Haven, Conn.--Yale School of Medicine researchers report the first demonstration that a single mutation in a human sodium channel gene can trigger pain in people with an inherited pain syndrome known as primary erythromelalgia, according to a study published this month in the journal Brain. The research provides novel insights into the molecular basis for altered firing of pain signaling neurons in primary erythromelalgia, according to Stephen Waxman, M.D., senior author of the study, chair of the Department of Neurology and director of the West Haven Veterans Administration Rehabilitation Research Center. DNA samples were studied from a family with 36 members, of which 17 exhibit symptoms typical of erythromelalgia--attacks of intense burning pain of the hands and feet triggered most commonly by heat and moderate exercise. There is currently no effective treatment for erythromelalgia. All 17 affected members of this family carried a mutation in the gene for sodium channel Nav1.7, one of the nine sodium channels. Nav1.7 is abundantly and preferentially present in small-diameter nerve fibers and free nerve endings within the peripheral nervous system and is associated with pain transmission. Previous studies linked primary erythromelalgia to two mutations in the gene coding for sodium channel Nav1.7. This study describes a third mutation in Nav1.7 and is evidence that mutant Nav1.7 predisposes its pain sensing neurons to become hyperexcitable and fire rapid bursts of signals at lower than normal stimulation. Hyperexcitability has long been considered a hallmark of painful neuropathies.

Keyword: Pain & Touch
Link ID: 7636 - Posted: 07.14.2005

Facial attractiveness and smell give us contradictory messages about how to select mates, new research has revealed. Previous research on smell suggests that humans prefer odours from potential partners who are genetically dis-similar. But new research in which women rated the facial attractiveness of men suggests the exact opposite. So sight and smell appear to be giving contradictory messages about which partners to choose. The new research investigated possible links between mate preference and the major histocompatibility complex (MHC) - the huge molecule on cells, unique to each individual, which helps our immune systems to distinguish native from alien cells. The underlying theory is that humans avoid the dangers of inbreeding, and maximise the chances of having genetically fitter children, by selecting partners who have a vastly different MHC from their own. That way, there is more chance of one parent’s genes compensating for faulty genes in the other. But how the senses pick up subliminal cues about someone else’s MHC is still something of a mystery. Most research so far has focused on smell, especially in rodents, and has backed up this basic assumption. Male and female mice, for example, usually select mates with different MHC, which they judge by smelling each others’ urine. Smell experiments in humans have broadly given the same message, showing that body odour is more appealing in people with vastly differing MHC. But new research in which women rated the attractiveness of men’s faces has bucked the trend, showing that women preferred faces of men with similar MHC. © Copyright Reed Business Information Ltd.

Keyword: Chemical Senses (Smell & Taste); Sexual Behavior
Link ID: 7635 - Posted: 06.24.2010

By Sean Coughlan A university research team says it has discovered why most people "hearing voices" in hallucinations say they hear male voices. Dr Michael Hunter's research at the University of Sheffield says that male voices are less complex to produce than female. As such, when the brain spontaneously produces its own "voices", a male voice is more likely to have been generated. Among both men and women, 71% of such "false" voices are male. "Psychiatrists believe that these auditory hallucinations are caused when the brain spontaneously activates, creating a false perception of a voice," says Professor Hunter of the university's psychiatry department. "The reason these voices are usually male could be explained by the fact that the female voice is so much more complex that the brain would find it much harder to create a false female voice accurately than a false male voice," he says. Such imaginary voices are typically likely to be middle-aged and carry "derogatory" messages. The research, published in NeuroImage, shows how the brain interprets information from human voices - and how female and male voices activate different parts of the brain. "The female voice is more complex than the male voice, due to differences in the size and shape of the vocal cords and larynx between women and men, and also due to women having greater natural 'melody' in their voices. (C)BBC

Keyword: Schizophrenia; Hearing
Link ID: 7634 - Posted: 07.14.2005