By Bruce Bower Oh what a tangled web we weave, when trying to determine who deceives. Virtually everyone, even those experienced at dealing with deceivers, detect others’ lies no better than would be expected by chance. Those sobering conclusions come from the first large-scale analysis of individual differences in deception detection. It takes two to tangle in deceptive encounters, note Charles Bond Jr. of Texas Christian University in Fort Worth and Bella DePaulo of the University of California, Santa Barbara. The two psychologists say their analysis of the findings to date suggest some people are relatively easy to read, while others shroud their intentions in mystery. A person’s perceived credibility, as reported by volunteers on questionnaires, rather than honesty, plays a major role in whether that person gets branded as a liar, Bond and DePaulo report in the July Psychological Bulletin. Certain people appear either honest or dishonest from the get-go, whether or not they’re telling the truth, the psychologists assert. Earlier research has found that baby-faced people seem credible whereas people who look nervous or avert their gaze typically get labeled untrustworthy. The new analysis shows that participants more often believe liars perceived as high in credibility than truth-tellers regarded as low in credibility. “When all the evidence is statistically analyzed, deception judgments depend more on the liar than the judge,” Bond says. © Society for Science & the Public 2000 - 2008

Keyword: Emotions; Stress
Link ID: 11779 - Posted: 06.24.2010

Scientists have known for a long time that sweet taste activates pleasure pathways in the brain. So, does consuming diet drinks really satisfy you? No, says Duke University neuroscientist Albino Oliveira-Maia; your brain can sense the missing calories. "Satisfaction that we take from eating and from food depends on a second pathway other than the taste," says Oliveira-Maia, "This pathway is a result of the caloric content — of the calories that are in the food that we are eating." He gave sugar water or water sweetened with sucralose (the non-caloric sweetener Splenda®) to specially-bred mice that could not taste sweetness. They used probes that recorded brain activity and matched that to special "lickometer" reading that recorded mouse licks from liquid dispensers. As reported in the journal Neuron, the researchers saw a response in the reward centers of animals that got sugar, but not in those fed the "diet" water. Oliveira-Maia says that "the dopamine system, which is involved in all kinds of reward — it's involved in taste — people have known for many years now that it's involved in addiction. It's also involved in how calories are impacting the brain reward system." © ScienCentral, 2000-2008.

Keyword: Obesity
Link ID: 11778 - Posted: 06.24.2010

By Victoria Stern The deadliest and most common type of brain cancer has a strange bedfellow: cytomegalovirus, a kind of herpes present in about 80 percent of the U.S. population. Now scientists are exploiting this coincidence to treat the cancer with a vaccine that targets the virus and slows tumor regrowth. In 2002 scientists showed that cytomegalovirus, or CMV, was active in the brain tumors but not the surrounding healthy tissue of all 27 patients they tested who had glioblastoma multiforme. CMV is dormant and undetectable in most people. Neuroscientist Duane Mitchell of Duke University Medical Center and his colleagues confirmed in 2007 that CMV is active in at least 90 percent of glioblastoma tumors. Now Mitchell’s team has developed an experimental vaccine that triggers the immune system to attack CMV, thereby attacking its tumor tissue home. As reported at the American Society of Clinical Oncology meeting in June, the vaccine, together with radiation and chemotherapy, prevented the brain tumor from reemerging after surgery for 12 months as compared with the typical six to seven months with no vaccine. Patients’ average life span increased from 14 months to more than 20. So does this herpes virus cause cancer? The answer is unclear: tumor cells may simply be a fertile ground for growing the virus, as cells such as these often lack the normal immune functions that suppress CMV reproduction. But University of Wisconsin–Madison researchers reported in May that the virus has the ability to take over a cell’s braking mechanism and cause uncontrolled reproduction. Even so, the numbers do not seem to add up: four of five Americans has CMV, but only about one in 30,000 ends up with glioblastoma. And a small number of glioblastoma patients do not have CMV in their tumors. © 1996-2008 Scientific American Inc.

Keyword: Glia; Neuroimmunology
Link ID: 11777 - Posted: 06.24.2010

By Tina Hesman Saey Hub systems may be frustrating for airline travelers, but a central hub keeps the brain connected and humming, a first-ever wiring diagram of the human brain reveals. Nearly all of the information transmitted from one brain region to another passes through a core located in the center and back of the brain along the crack that separates the two hemispheres, an international group of researchers reports in the June 30 PLoS Biology. Earlier research pinpointed an area of the brain called the default network — a group of brain regions that are active when a person is thinking about nothing in particular. The new map of the brain’s anatomy showed that, in fact, the default network also resides in this physical hub, the core of the brain. “Our map is a very crude one,” says Olaf Sporns, a computational neuroscientist at Indiana University in Bloomington. But the wiring diagram is a first step toward understanding how the brain is structured and how it communicates. Such diagrams could help therapists design strategies to improve recovery of stroke victims or people with other brain injuries. © Society for Science & the Public 2000 - 2008

Keyword: Stroke; Brain imaging
Link ID: 11776 - Posted: 06.24.2010

Amber Dance Mice engineered to have abnormal brain chemistry surprised researchers with their unpredictable deaths -- and may be one of the best models yet for sudden infant death syndrome (SIDS), also known as cot death. In a new study published in Science1, researchers changed the control of serotonin, a neurotransmitter, in the mice. Serotonin is important in the autonomic nervous system, which controls unconscious functions such as heart beat and digestion. The engineered mice showed symptoms that mirror human SIDS: sudden drops in heart rate and frequent deaths in early life. The majority of them died before reaching three months of age. Cot death often claims its victims while napping, which could suggest future lines of research into serotonin and sleep.PunchstockSIDS is the label for unexplained deaths in babies less than one year old, and is the leading cause of death in infants aged 1–12 months in the developed world. Previous research suggested that serotonin played a role in SIDS, and the new study adds weight to that theory. Cornelius Gross and colleagues at the European Molecular Biology Laboratory, in Monterotondo, Italy, created mice with excess levels of the serotonin 1A receptor (Htr1a). Htr1a is like a thermostat for serotonin levels — when the receptor binds serotonin, it dampens serotonin production, keeping levels from getting too high. © 2008 Nature Publishing Group

Keyword: Sleep
Link ID: 11775 - Posted: 06.24.2010

Almost half of all women in their 90s are suffering from dementia, Californian research suggests. The analysis of more than 900 people aged 90 or over, published in the journal Neurology, found it was far less likely in men of the same age. The reasons are not clear - although older women are more prone to stroke and heart disease, both risk factors for dementia. There are fears dementia could place a great strain on health services. There have been few studies looking specifically at dementia in very old people, even though increases in life-expectancy mean that this is a fast-growing group. Other studies have shown that dementia prevalence increases for both men and women between the ages of 65 and 85. However, the Californian research found that the likelihood of having dementia doubled every five years in women after reaching 90, but not in men. A total of 45% of the women had dementia, compared with 28% of men. It also suggested that women who had received higher education were much less likely to develop dementia than those with a lower level of education. Dr Maria Corrada, who led the study, said: "As more and more people reach age 90, our findings provide further evidence that more needs to be done to provide adequate resources to care for the increasing number of very old people with memory problems." A recent report by the King's Fund suggested that the burden of dementia in the UK was likely to rise sharply over the next two decades as the population aged. (C)BBC

Keyword: Alzheimers
Link ID: 11774 - Posted: 07.03.2008

A fascinating case of foreign accent syndrome recently cropped up in southwestern Ontario, says a new report published by researchers at McMaster University. The rare syndrome affects people who have had a stroke, causing them to speak in a different accent than the one they had before the stroke. It is usually occurs after a stroke damages the areas of the left hemisphere of the brain related to speech production, such as Broca's area, pre-motor and motor areas and the basal ganglia. Broca's area is a section of the brain found in the frontal lobe that's connected to speech, while the basal ganglia is responsible for movement. Rosemary Dore, 50, of Windsor, Ont., had a left-sided stroke that left her with an accent similar to the Canadian East Coast accent, though she had formerly had a southern Ontario accent. Dore had lived in southern Ontario all of her life and only travelled to Florida on vacation. She had never been to the East Coast nor did she have any family members with East Coast accents. Her case is the first of its kind reported in Canada, the McMaster researchers said, and one of fewer than 20 cases reported worldwide. Researchers gave Dore a CT scan, which revealed various changes in the brain consistent with an ischemic stroke. One month after the stroke, she was tested and found to have 100 per cent speech intelligibility. © CBC 2008

Keyword: Stroke; Language
Link ID: 11773 - Posted: 06.24.2010

Marco Iacoboni, a neuroscientist at the University of California at Los Angeles, is best known for his work on mirror neurons, a small circuit of cells in the premotor cortex and inferior parietal cortex. What makes these cells so interesting is that they are activated both when we perform a certain action—such as smiling or reaching for a cup—and when we observe someone else performing that same action. In other words, they collapse the distinction between seeing and doing. In recent years, Iacoboni has shown that mirror neurons may be an important element of social cognition and that defects in the mirror neuron system may underlie a variety of mental disorders, such as autism. His new book, Mirroring People: The Science of How We Connect to Others, explores these possibilities at length. Mind Matters editor Jonah Lehrer chats with Iacoboni about his research. LEHRER: What first got you interested in mirror neurons? Did you immediately grasp their explanatory potential? IACOBONI: I actually became interested in mirror neurons gradually. [Neuroscientist] Giacomo Rizzolatti and his group [at the University of Parma in Italy] approached us at the UCLA Brain Mapping Center because they wanted to expand the research on mirror neurons using brain imaging in humans. I thought that mirror neurons were interesting, but I have to confess I was also a bit incredulous. We were at the beginnings of the science on mirror neurons. The properties of these neurons are so amazing that I seriously considered the possibility that they were experimental artifacts. In 1998 I visited Rizzolatti’s lab in Parma, I observed their experiments and findings, talked to the anatomists that were studying the anatomy of the system and I realized that the empirical findings were really solid. At that point I had the intuition that the discovery of mirror neurons was going to revolutionize the way we think about the brain and ourselves. However, it took me some years of experimentation to fully grasp the explanatory potential of mirror neurons in imitation, empathy, language, and so on—in other words in our social life. © 1996-2008 Scientific American Inc.

Keyword: Vision; Emotions
Link ID: 11772 - Posted: 06.24.2010

By: Robert Kunzig If there is one thing that has always seemed obvious about homosexuality, it's that it just doesn't make sense. Evolution favors traits that aid reproduction, and being gay clearly doesn't do that. The existence of homosexuality amounts to a profound evolutionary mystery, since failing to pass on your genes means that your genetic fitness is a resounding zero. "Homosexuality is effectively like sterilization," says psychobiologist Qazi Rahman of Queen Mary College in London. "You'd think evolution would get rid of it." Yet as far as historians can tell, homosexuality has always been with us. So the question remains: If it's such a disadvantage in the evolutionary rat race, why was it not selected into oblivion millennia ago? Twentieth-century psychiatry had an answer for this Darwinian paradox: Homosexuality was not a biological trait at all but a psychological defect. It was a mistake, one that was always being created anew, in each generation, by bad parenting. Freud considered homosexuality a form of arrested development stamped on a child by a distant father or an overprotective mother. Homosexuality was even listed by the American Psychiatric Association as a mental disorder, and the idea that gays could and should be "cured" was widely accepted. But modern scientific research has not been kind to that idea. It turns out that parents of gay men are no better or worse than those of heterosexuals. And homosexual behavior is common in the animal kingdom, as well—among sheep, for instance. It arises naturally and does not seem to be a matter of aloof rams or overbearing ewes. © Copyright 1991-2008 Sussex Publishers, LLC

Keyword: Sexual Behavior; Genes & Behavior
Link ID: 11771 - Posted: 06.24.2010

Ewen Callaway With jam-packed schedules and a video feed to Earth, astronauts enjoy precious little privacy as it is. Soon, doctors might peek into an astronaut's last bastion of solitude, thanks to a portable brain scanner that could one day go into orbit. Mission control could use the device to remotely monitor astronauts for signs of brain injury, depression and even mental fatigue that could compromise their ability to make a critical repair of equipment. "If you had a magic cap to say, 'Are you good to go?' that might be valuable," says Jonathan Clark of the National Space Biomedical Research Institute (NSBRI) in Houston, Texas, US, which funds the work. "Think of it like a breathalyser for the brain." But the scanner, currently under development at Massachusetts General Hospital in Boston, US, must prove its worth and safety before NASA even considers sending a brain scanner into orbit, Clark tells New Scientist. Unlike the hulking, tunnel-like MRI machines that peer into the brain with super-strong magnets, the space brain scanner resembles a large remote control tethered to a Velcro headband by long, thin wires. Yet the technology – called near-infrared optical spectroscopy – works something like functional MRI, which equates changes in blood flow to brain activity.

Keyword: Brain imaging
Link ID: 11770 - Posted: 06.24.2010

By Greg Miller More than a year after taking a hallucinogenic drug in a carefully controlled experiment, most people rate the experience among the most personally meaningful and spiritually significant of their lives, researchers report online today in the Journal of Psychopharmacology. Such findings are helping to renew interest in research with hallucinogens, a field whose reputation long suffered from the psychedelic excesses of the 1960s. The new study follows up with 36 volunteers who participated in earlier experiments led by psychopharmacologist Roland Griffiths of Johns Hopkins University in Baltimore, Maryland. The researchers monitored the mostly middle-aged subjects while they took a strong dose of psilocybin, the active ingredient in hallucinogenic mushrooms. All of the volunteers had indicated at least some participation in religious or spiritual activities--such as meditating or going to church--and the researchers instructed them to direct their attention inward while under the drug's sway. None had previous experience with hallucinogens. On questionnaires completed after the drug had worn off, and again 2 months later, they rated the experience as highly significant, the researchers reported in a 2006 paper in Psychopharmacology. Volunteers frequently described a sense of greater truth or a sense of the unity of all things while on the drug, for example. The experience remained highly significant to most of the volunteers 14 months later, the researchers now report: 58% rated it among the five most personally meaningful experiences of their lives and 67% rated it among the five most spiritually significant. © 2008 American Association for the Advancement of Science

Keyword: Drug Abuse
Link ID: 11769 - Posted: 06.24.2010

Alison Abbott The director of a top laboratory in Germany has charged that two of his former research students took data from his laboratory without his permission and published scientifically incorrect interpretations of them against his advice. One of the two editors-in-chief of Human Brain Mapping, Peter Fox of the University of Texas Health Science Center in San Antonio, told Nature that the paper was correctly refereed, but declined to add details. Logothetis is furious about the publication of data, which he believes will mislead the field, and about the fact that the authors of the paper allege that he tried to stop them publishing the data for personal reasons. The affair began in the spring, when Amir Shmuel, who worked in Logothetis's laboratories from 2002 to 2007 and is now at the Montreal Neurological Institute of McGill University in Canada, asked Logothetis for permission to use data generated there. Although he agreed at first, Logothetis withdrew his permission when he realized that the data — from functional magnetic resonance imaging studies on monkey brains — were being used to support a theory about spontaneous brain activity. The data had been collected when monkeys were looking at a grey but flickering LED screen. “The protocol was just inappropriate for analysis of spontaneous brain activity,” says Logothetis. © 2008 Nature Publishing Group –

Keyword: Brain imaging
Link ID: 11768 - Posted: 06.24.2010

-- Thanks to salt and hot chili peppers, researchers have found a calculus-computing center that tells a roundworm to go forward toward dinner or turn to broaden the search. It's a computational mechanism, they say, that is similar to what drives hungry college students to pizza. These behavior-driving calculations, according to a paper published in the July 3 issue of the journal Nature, are done "in a tiny, specialized computer inside a primitive roundworm," says principal investigator Shawn Lockery, a University of Oregon biologist and member of the UO Institute of Neuroscience. In their paper, the researchers documented how two related, closely located chemosensory neurons, acting in tandem, regulate behavior. The left neuron controls an on switch, while the opposing right one an off switch. These sister neurons are situated much like the two nostrils or two eyes of mammals. Together these neurons are known as ASE for antagonistic sensory cues. It's possible, Lockery said, that the discovery someday could help research aimed at treating at least some of the 200,000 people in the United States who annually seek medical treatment, according to records of the National Institutes of Health, for problems involving taste and smell. © University of Oregon

Keyword: Chemical Senses (Smell & Taste)
Link ID: 11767 - Posted: 06.24.2010

If we learned language in the same way that we learn to add, subtract or play cards, children like Barry would not get much beyond hello and goodbye. Nor, for that matter, would normal toddlers. As anyone who has struggled through college French can attest, picking up a new language as an adult is as simple as picking up a truck. Yet virtually every kid in the world succeeds at it-and without conscious effort. Children attach meanings to sounds long before they shed their diapers. They launch into grammatical analysis before they can tie their shoes. And by the age of 8, most produce sentences as readily as laughter or tears. Scholars have bickered for centuries over how kids accomplish this feat, but most now agree that their brains are wired for the task. Like finches or sparrows, which learn to sing as hatchlings or not at all, we're designed to acquire certain kinds of knowledge at particular stages of development. Children surrounded by words almost always become fluent by 8, whatever their general intelligence. And people deprived of language as children rarely master it as adults, no matter how smart they are or how intensively they're trained. As MIT linguist Steven Pinker observes in his acclaimed 1994 book "The Language Instinct," "Language is not a cultural artifact that we learn the way we learn to tell time or how the federal government works. It is a distinct piece of [our] biological makeup." Whether they emerge speaking Spanish, Czech or Hindi, kids all acquire language on the same general schedule. And as a growing body of research makes clear, they all travel the same remarkable path. © 2008 Newsweek, Inc

Keyword: Language; Development of the Brain
Link ID: 11766 - Posted: 06.24.2010

Mice given the equivalent of six to eight cups of coffee a day were less likely to develop a disease similar to multiple sclerosis, a study found. Researchers hope this could lead to new ways to prevent MS in humans. The Proceedings of the National Academy of Sciences journal reported that the caffeine appeared to prevent nervous system damage. However, experts recommend no more than five cups a day, amid evidence higher doses can worsen diabetes. While the chain reaction which leads to multiple sclerosis is still not fully understood, a key moment surrounds the entry of immune cells into the central nervous system. Once there, they trigger "autoimmune" attacks, gradually and progressively destroying the fatty myelin sheaths that protect nerves. Current treatments for MS are limited only to slowing the progress of the disease once it is established. At Cornell University in the US, and Turku University in Finland, the researchers are using a mouse disease called "experimental autoimmune encephalomyelitis", or EAE, to mimic the development of MS in humans. One of the effects of caffeine in both mice and humans affects a molecule called adenosine, which plays a role in sleep and energy production. When mice were dosed with caffeine, adenosine could not link to a particular receptor on the surface of cells. This in turn appeared to have an indirect effect on the ability of immune cells to enter the nervous system at a part of the brain called the choroid plexus, and the mice did not develop EAE. While the precise reason this happened was not clear, the researchers suggested the adenosine blocking effect led to a lower number of "adhesion molecules" - needed by the immune cells to gain entry - on the surface of the choroid plexus. (C)BBC

Keyword: Multiple Sclerosis; Neuroimmunology
Link ID: 11765 - Posted: 07.01.2008

By Shankar Vedantam In Bethesda, a 15-year-old girl talks to her television set. Often, she seems more connected to the tube's ghostly embrace than to her own father, mother, brothers and sister. She flushes household items down the toilet. She has no friends outside her family. Rachel does not understand why other people might not want to talk about her beloved Japanese animation shows. She gets angry when anyone shows a lack of interest in the things that interest her. Rachel has autism, and there are tens of thousands of children like her. Having a child like Rachel -- especially at a time of widespread fears that something in children's vaccines is responsible for surging rates of diagnosis in the United States -- is debilitating, dispiriting, demoralizing. Many families are worried by allegations that the medical establishment is covering up the risks of childhood shots, possibly because doctors have financial conflicts of interests with vaccine manufacturers or because health officials are worried about the consequences of lowered vaccination rates. "It is an ever- increasing snowball of horror -- one disappointment after another," Rachel's father, Peter Hotez, says about the challenge of dealing with an autistic child. "You recognize the gravity now as she has become a difficult and impossible teenager." © 2008 The Washington Post Company

Keyword: Autism
Link ID: 11764 - Posted: 06.24.2010

By Nikhil Swaminathan Researchers have discovered that a drug marketed to slow the progression of memory loss in Alzheimer's disease may also prevent brain damage in as many as 35 percent of premature infants. Scientists at Children's Hospital Boston in a study published in The Journal of Neuroscience say they used memantine (brand name Namenda) to stop strokes‚Äîthat would result in learning difficulties, behavioral problems and faulty motor function‚Äîin rats. The researchers hope to receive permission sometime in the next five years to test their new treatment in premature babies who suffer strokes. Thanks to medical and technological strides, children as young as 23 weeks old (average pregnancy is about 40 weeks) are now able to survive, according to study co-author and neurologist Frances Jensen. But infants this young have less oxygen in their blood‚Äîbecause their lungs are not fully functional and their breathing is labored‚Äîleaving them prone to strokes (caused by a lack of oxygen to the brain). Preemies "are a very very fragile group of patients," Jensen says, adding that the strokes are the main cause of cerebral palsy‚Äîan incurable neurological disorder that affects the motor function of 500,000 people in the U.S., with 8,000 infants diagnosed yearly. © 1996-2008 Scientific American Inc.

Keyword: Development of the Brain
Link ID: 11763 - Posted: 06.24.2010

By BENEDICT CAREY The outer layer of the brain, the reasoning, planning and self-aware region known as the cerebral cortex, has a central clearinghouse of activity below the crown of the head that is widely connected to more-specialized regions in a large network similar to a subway map, scientists reported Monday. The new report, published in the free-access online journal PLoS Biology, provides the most complete rough draft to date of the cortex’s electrical architecture, the cluster of interconnected nodes and hubs that help guide thinking and behavior. The paper also provides a striking demonstration of how new imaging techniques focused on the brain’s white matter — the connections between cells, rather than the neurons themselves — are filling in a dimension of human brain function that has been all but dark. In previous studies, scientists have used magnetic resonance imaging to identify peaks and valleys of neural activity when people are doing various things, like making decisions, reacting to frightening images or reliving painful memories. But these studies, while provocative, revealed virtually nothing about the underlying neural networks involved — about which brain regions speak to one another and when. Previous estimates of network structure, based on such imaging, have been sketchy. The new findings, while not conclusive, give scientists what is essentially a wiring diagram that they can test and refine. Copyright 2008 The New York Times Company

Keyword: Brain imaging
Link ID: 11762 - Posted: 06.24.2010

By GINA KOLATA On Dec. 18, 2005, Ariel Sharon, then Israel’s prime minister, was taken to a Jerusalem hospital with symptoms of a stroke, unable to speak or understand what others were saying. Over the next 36 hours, his doctors found themselves in a quandary. Mr. Sharon had two conditions that might lead to a new and devastating stroke. And treating one condition could make the other one worse. First, he was susceptible to blood clots that could be swept from his heart to his brain, causing a major stroke. Anticlotting drugs might protect him. But his brain scans showed microbleeds, pinpoint drops of blood that leaked from blood vessels in the brain. The fear was that an anticlotting drug might turn a new microbleed into a life-threatening, incapacitating hemorrhagic stroke. Until recently, microbleeds were all but unknown. Now, with improved scans, they are turning up constantly; one recent study found them in the brains of 1 out of 5 people age 60 and older. And they are leading to a classic conundrum of modern medicine: Just because something turns up on an M.R.I. scan, is it significant? And if it may or may not be significant, what to do about it? Copyright 2008 The New York Times Company

Keyword: Stroke
Link ID: 11761 - Posted: 06.24.2010

Lucas Laursen Researchers have devised a treatment that mechanically repairs burst cell membranes in the brain, somewhat like puncture sealants used in bicycle tyres, and could therefore help to avert brain damage after serious head injuries. Brain-injured rats that are injected with a polymer called polyethylene glycol (PEG) soon after their injuries recover certain behavioural abilities better than untreated rats, report researchers in this week’s Journal of Biological Engineering 1. PEG, a commonly available substance already used medically for stomach pumping, has reached clinical testing with naturally injured dogs, a step towards human testing. It is one of several polymers and sugars that show potential for reducing the impact of blunt traumas to the brain, according to author Richard Borgens of Purdue University in West Lafayette, Indiana. The therapy "does not require sophisticated technology", says Borgens, "it requires sophisticated thinking". He says it acts by absorbing water, promoting the healing of cell membranes and preventing "the exchange of things that cause decay and degeneration of the cell". Once it reaches human trials, PEG could be carried by trauma units and administered as soon as emergency crews reach victims of blunt-force trauma. © 2008 Nature Publishing Group

Keyword: Brain Injury/Concussion
Link ID: 11760 - Posted: 06.24.2010