Linda Geddes Birds may not be as "bird-brained" as we thought. Zebra finches show many features of sleep, which had previously been assumed to be the sole preserve of mammals. The finding raises new questions about the complexity of the bird brain and about the evolution of sleep as we know it. Mammalian sleep is characterised by distinct stages: slow wave sleep (SWS), intermediate sleep (IS) and rapid-eye-movement (REM) sleep, with a progression towards more REM sleep. EEG recordings of the brain's electrical activity also show specific landmarks called "K-complexes" and "spindles" during SWS. Since K-complexes had only ever been observed in mammals, neuroscientists assumed that a neocortex – an area of the brain involved in higher functions such as conscious thought and language – was needed to generate them. Philip Low at the Salk Institute for Biological Sciences in La Jolla, California, US, and his colleagues monitored five zebra finches during the night, tracking eye and body movements, and brain activity. © Copyright Reed Business Information Ltd.

Keyword: Sleep; Evolution
Link ID: 11749 - Posted: 06.24.2010

Fishing in the stream of consciousness, researchers now can detect our intentions and predict our choices before we are aware of them ourselves. The brain, they have found, appears to make up its mind 10 seconds before we become conscious of a decision -- an eternity at the speed of thought. Their findings challenge conventional notions of choice. "We think our decisions are conscious," said neuroscientist John-Dylan Haynes at the Bernstein Center for Computational Neuroscience in Berlin, who is pioneering this research. "But these data show that consciousness is just the tip of the iceberg. This doesn't rule out free will, but it does make it implausible." Through a series of intriguing experiments, scientists in Germany, Norway and the U.S. have analyzed the distinctive cerebral activity that foreshadows our choices. They have tracked telltale waves of change through the cells that orchestrate our memory, language, reason and self-awareness. In ways we are only beginning to understand, the synapses and neurons in the human nervous system work in concert to perceive the world around them, to learn from their perceptions, to remember important experiences, to plan ahead, and to decide and act on incomplete information. In a rudimentary way, they predetermine our choices. Copyright © 2008 Dow Jones & Company, Inc

Keyword: Emotions
Link ID: 11748 - Posted: 06.24.2010

By SAM WANG and SANDRA AAMODT FALSE beliefs are everywhere. Eighteen percent of Americans think the sun revolves around the earth, one poll has found. Thus it seems slightly less egregious that, according to another poll, 10 percent of us think that Senator Barack Obama, a Christian, is instead a Muslim. The Obama campaign has created a Web site to dispel misinformation. But this effort may be more difficult than it seems, thanks to the quirky way in which our brains store memories — and mislead us along the way. The brain does not simply gather and stockpile information as a computer’s hard drive does. Facts are stored first in the hippocampus, a structure deep in the brain about the size and shape of a fat man’s curled pinkie finger. But the information does not rest there. Every time we recall it, our brain writes it down again, and during this re-storage, it is also reprocessed. In time, the fact is gradually transferred to the cerebral cortex and is separated from the context in which it was originally learned. For example, you know that the capital of California is Sacramento, but you probably don’t remember how you learned it. This phenomenon, known as source amnesia, can also lead people to forget whether a statement is true. Even when a lie is presented with a disclaimer, people often later remember it as true. With time, this misremembering only gets worse. A false statement from a noncredible source that is at first not believed can gain credibility during the months it takes to reprocess memories from short-term hippocampal storage to longer-term cortical storage. Copyright 2008 The New York Times Company

Keyword: Learning & Memory
Link ID: 11747 - Posted: 06.24.2010

Not many people think about what it's like to be a bat, but for those who do, it's enlightening and potentially groundbreaking for understanding aspects of the human brain and nervous system. Cynthia Moss, a member of the Neuroscience and Cognitive Science program at the University of Maryland, College Park, Md., is one of few researchers who spend time trying to get into the heads of bats. Her new research suggests there is more to studying bats than figuring out how they process sound to distinguish environments. Partially supported by the National Science Foundation, her research paper appears in the June 18 online edition of the Proceedings of the National Academy of Sciences. "For decades it's been recognized that a bat's voice produces sounds that give the bat information about the location of objects," says Moss. "We're now recognizing that every time a bat produces a sound there are changes in brain activity that may be important for scene analysis, sensorimotor control and spatial memory and navigation." The research could help neurobiologists understand mechanisms in the human brain and ultimately benefit human health, but that may not happen for some time as more research is needed.

Keyword: Hearing
Link ID: 11746 - Posted: 06.28.2008

Scientists have located a region of the brain that encourages humans to indulge in adventurous behaviour. Sophisticated scans showed the region, located in a primitive area of the brain, is activated when people choose unfamiliar options. The researchers believe this suggests that taking a chance is an ancient human trait that may have given humans an evolutionary advantage. The University College London study features online in the journal Neuron. The research took place at UCL's Wellcome Trust Centre for Neuroimaging. Volunteers were shown a selection of images with which they had already been made familiar. Each card had a unique probability of reward attached to it and, over the course of the experiment, the volunteers would be able to work out which selection would provide the highest rewards. However, when unfamiliar images were introduced the researchers found that volunteers were more likely to take a chance and select one of these options than continue with their familiar - and arguably safer - option. Using fMRI scanners, which measure blood flow in the brain to highlight which areas are most active, the researchers showed that when the subjects selected an unfamiliar option an area of the brain known as the ventral striatum lit up, indicating that it was more active. The ventral striatum is in one of the evolutionarily primitive regions of the brain - suggesting that the process can be advantageous and will be shared by many animals. Lead researcher Dr Bianca Wittmann said: "Seeking new and unfamiliar experiences is a fundamental behavioural tendency in humans and animals." (C)BBC

Keyword: Emotions
Link ID: 11745 - Posted: 06.26.2008

By Diane Mapes For Tiffanie Williams, a marketing executive from Boston, it’s chips and salsa and sappy movie marathons. For Paul Niemi, a communications specialist from Manhattan, it’s Chinese food and long weekends in bed. And for Susan Biali, a physician and life coach who splits her time between Vancouver, Canada, and Cabo San Lucas, Mexico, it’s skipped meals and late nights glued to the computer. Say hello to the many faces of stress. While health experts urge people to exercise, eat right and get enough sleep in order to keep stress and its harmful effects at bay, many of us tend to fall into all-too-predictable and all-too-unhealthy patterns when life gets out of whack — we smoke more, we drink more, we ignore the gym and make tracks for the shopping mall. But the place stress seems to hammer us the hardest is right where we live: in our bedrooms and bellies. In an October 2007 American Psychological Association study, nearly half of the 2,000 surveyed (48 percent) said they’d lost sleep during the last month thanks to stress, 36 percent said they’d skipped a meal during the last month because of pressure and 43 percent said stress caused them to overeat or eat unhealthy foods. Yes, stress makes us eat more. Or eat less. It keeps us awake at night. Or sends us into hiding in our beds. These stress responses often pair up to form “coping combos.” Some people are sleepers who can’t eat while others are insomniacs who eat too much. There are non-sleepers who pick at their food and sleepyheads who repeatedly surrender to the siren song of the starch cupboard. © 2008 MSNBC Interactive

Keyword: Stress
Link ID: 11744 - Posted: 06.24.2010

By Nikhil Swaminathan A drug already on the market for a completely unrelated condition could be used to treat a form of mental retardation linked to autism—if the results of a study in mice hold up, researchers report. Scientists used rapamycin—a medication doctors prescribe to patients who have had transplants to prevent their bodies from rejecting the new organs—to treat learning disorders associated with a disease called tuberous sclerosis complex (TSC) in mice. TSC is a rare genetic disorder that causes brain tumors, seizures, learning disabilities, skin lesions and kidney tumors in the 50,000 Americans and one million people worldwide who have the disease. Half of those with TSC are autistic, and as many as one in five people with the condition also suffer from mental retardation, so the hope is that rapamycin may be used to treat learning disabilities and short-term memory deficits in all kinds of autism as well, says neurobiologist and co-author of a study in Nature Medicine, Alcino Silva of the David Geffen School of Medicine at the University of California, Los Angeles. Silva and his colleagues created mice with TSC by removing one copy of the gene TSC2. (If researchers delete both copies of the gene, the resulting mice die shortly after birth.) When the both copies of the gene are turned on in either mice and humans, they produce and regulate proteins that help strengthen connections between nerve cells, which the brain needs to remember and learn. © 1996-2008 Scientific American Inc.

Keyword: Development of the Brain; Genes & Behavior
Link ID: 11743 - Posted: 06.24.2010

Philip Ball When Snowball, a sulphur-crested male cockatoo, was shown last year in a YouTube video apparently moving in time to pop music, he became an Internet sensation. But only now has his performance been subjected to scientific scrutiny. And the conclusion is that Snowball really can dance. Aniruddh Patel of the Neurosciences Institute in La Jolla, California, and his colleagues say that Snowball’s ability to shake his stuff is much more than a cute curiosity. It could shed light on the biological bases of rhythm perception, and might even hold implications for the use of music in treating neurodegenerative disease. "Music with a beat can sometimes help people with Parkinson’s disease to initiate and coordinate walking," says Patel. "But we don’t know why. If non-human animals can synchronize to a beat, what we learn from their brains could be relevant for understanding the mechanisms behind the clinical power of rhythmic music in Parkinson’s." Anyone watching Snowball can see that his bopping seems to be well synchronized with the beat. But it was possible that in the original videos he was using timing cues from people dancing off camera. His previous owner says that he and his children would encourage Snowball’s ‘dancing’ with rhythmic gestures of their own. © 2008 Nature Publishing Group

Keyword: Hearing; Parkinsons
Link ID: 11742 - Posted: 06.24.2010

A. One term used in studying the phenomenon is saccular acoustical sensitivity (the saccule is a bed of sensory cells in the inner ear), but the goosebumps and extreme aversion are unexplained. Furthermore, recent research into sounds that drive people crazy ranks screeching blackboards well below several other sounds, like vomiting. Trevor J. Cox of the Acoustics Research Centre at the University of Salford in England has done extensive research on nasty noises using a Web site, www.sound101.org, that allows people to rate their reactions to 34 repellent or disgusting sounds. After thousands of responses, vomiting is in the lead. Other top offenders are crying babies, microphone feedback and a dentist’s drill. The blackboard screech comes in at No. 16. Mr. Cox suggested in the journal Applied Acoustics early this year that the reaction to vomiting might be partly related to an inborn desire to avoid sick people and thus infection, but that cultural and etiquette factors might also be involved. Copyright 2008 The New York Times Company

Keyword: Hearing
Link ID: 11741 - Posted: 06.24.2010

By LAURIE TARKAN Ramona Lamascola thought she was losing her 88-year-old mother to dementia. Instead, she was losing her to overmedication. Last fall her mother, Theresa Lamascola, of the Bronx, suffering from anxiety and confusion, was put on the antipsychotic drug Risperdal. When she had trouble walking, her daughter took her to another doctor — the younger Ms. Lamascola’s own physician — who found that she had unrecognized hypothyroidism, a disorder that can contribute to dementia. Theresa Lamascola was moved to a nursing home to get these problems under control. But things only got worse. “My mother was screaming and out of it, drooling on herself and twitching,” said Ms. Lamascola, a pediatric nurse. The psychiatrist in the nursing home stopped the Risperdal, which can cause twitching and vocal tics, and prescribed a sedative and two other antipsychotics. “I knew the drugs were doing this to her,” her daughter said. “I told him to stop the medications and stay away from Mom.” Not until yet another doctor took Mrs. Lamascola off the drugs did she begin to improve. The use of antipsychotic drugs to tamp down the agitation, combative behavior and outbursts of dementia patients has soared, especially in the elderly. Sales of newer antipsychotics like Risperdal, Seroquel and Zyprexa totaled $13.1 billion in 2007, up from $4 billion in 2000, according to IMS Health, a health care information company. Copyright 2008 The New York Times Company

Keyword: Alzheimers; Schizophrenia
Link ID: 11740 - Posted: 06.24.2010

By Rob Stein Is there such a thing as a "gay brain"? And, if so, are some people born with brains that make them more likely to be homosexual? Or do the brains of gay people develop differently in response to experiences? Those are some of the thorny questions that have been raised by a provocative new study that found striking differences between the brains of homosexuals and heterosexuals in both men and women. Some scientists say the new findings are part of an increasingly convincing body of evidence that suggests sexual orientation results from fundamental developmental differences that are probably caused by hormonal exposures in the womb. "This research is pointing to basic differences in the brain between homosexual and heterosexual people that are likely there right from the beginning," said Sandra F. Witelson, a professor of psychiatry and behavioral neurosciences at McMaster University in Ontario. "These could be reflecting some genetic or hormonal factors that predetermine your sexual orientation." Others, however, argue that such research is far from conclusive. "I remain skeptical," said William Byne, a professor of psychiatry at Mount Sinai School of Medicine in New York. "There's been a history of jumping to conclusions and overinterpreting findings in this field." © 2008 The Washington Post Company

Keyword: Sexual Behavior
Link ID: 11739 - Posted: 06.24.2010

Scientists have long questioned whether the abundant amounts of amyloid plaques found in the brains of patients with Alzheimer's actually caused the neurological disease or were a by-product of its progress. Now, using new research techniques, scientists have shown that a two-molecule aggregate (or dimer) of beta-amyloid protein fragments may play a role in initiating the disease. The study, supported by the National Institutes of Health, suggests a possible new target for developing drug therapies to combat the irreversible and progressive disorder. Ganesh M. Shankar, Ph.D., and Dennis J. Selkoe, M.D., of Brigham and Women's Hospital and Harvard Medical School, conducted the study in collaboration with other researchers at Harvard and in Ireland at University College Dublin, Beaumont Hospital and Royal College of Surgeons Ireland, and Trinity College Dublin. The National Institute on Aging (NIA), part of NIH, funded the study which appears online in the June 22, 2008, Nature Medicine. Alzheimer's disease is marked by the build-up of plaques consisting of beta-amyloid protein fragments, as well as abnormal tangles of tau protein found inside brain cells. Early in the disease, Alzheimer's pathology is first observed in the hippocampus, the part of the brain important to memory, and gradually spreads to the cerebral cortex, the outer layer of the brain. In this study, researchers tested cerebral cortex extracts from brains donated for autopsy by people aged 65 and older with Alzheimer's and other dementias, as well as those without dementia. The extracts contained soluble one-molecule (monomer), two-molecule (dimer), three-molecule (trimer) or larger aggregates of beta-amyloid, as well as insoluble plaque cores. The researchers then injected the extracts into normal rats or added the extracts to slices of normal mouse hippocampus.

Keyword: Alzheimers
Link ID: 11738 - Posted: 06.24.2008

Jennifer Viegas -- Neanderthals were hardly a weak group just before their extinction around 30,000 years ago, suggests new research. On the contrary, Britain's last Neanderthals had sophisticated weapons and lived in strategic spots, demonstrating impressive command of their territory. Archaeologists analyzing 180 flint tools and weapons, which survived an original collection of 2,300 artifacts found in 1900 at a site called Beedings near Pulborough, England, have traced them to the Neanderthals, according to an announcement made today by the University College London Institute of Archeology. The discoveries were also recently reported in British Archeology magazine. "The tools we've found at the site are technologically advanced and potentially older than tools in Britain belonging to our own species," said UCL's Matthew Pope. "It's exciting to think that there's a real possibility these were left by some of the last Neanderthal hunting groups to occupy northern Europe," he added. "The impression they give is of a population in complete command of both landscape and natural raw materials with a flourishing technology -- not a people on the edge of extinction." Pope is leading the recent excavations after Roger Jacobi of the Ancient Human Occupation of Britain Project first linked the tools to others discovered in northern Europe, which dated to between 35,000 and 42,000 years ago. The Beedings collection, however, is more diverse and extensive than any others from the region. © 2008 Discovery Communications, LLC

Keyword: Evolution
Link ID: 11737 - Posted: 06.24.2010

By Jennifer Couzin A stroke drug known as tPA, or tissue plasminogen activator, has been a lightning rod since it was first approved in the United States in 1996. Although studies have found that the drug can reduce the brain damage wrought by strokes, it can also cause potentially fatal bouts of cerebral bleeding. Now a team of researchers has identified one reason for tPA's ill effect. And it turns out that in mice, the problem can be eased by administering a cancer drug. TPA works by dissolving blood clots. That helps to restore blood flow to the brain after a stroke, potentially preventing additional brain cells from dying. tPA is only recommended if it can be given within 3 hours of a stroke; otherwise, doctors deem that the drug will do more harm than good, causing hemorrhages in the brain. One clue to why tPA can cause bleeding came several years ago. Vascular biologist Daniel Lawrence of the University of Michigan, Ann Arbor, found that in mice the drug appeared to damage the blood-brain barrier, a membrane that protects brain cells from toxins in the rest of the body. Soon after, in an entirely separate study, molecular biologist Ulf Eriksson and colleagues at the Karolinska University Hospital in Stockholm, Sweden, found a new target of tPA: a molecule called platelet-derived growth factor-CC (PDGF-CC), which helps drive blood vessel formation. Why this might matter wasn't clear at the time, however, and it did not seem connected to tPA's clot-busting power. But drugs often have more than one molecular target, including targets not relevant to the diseases they're designed to treat. © 2008 American Association for the Advancement of Science.

Keyword: Stroke
Link ID: 11736 - Posted: 06.24.2010

Kerri Smith General anaesthetics can worsen postoperative pain, suggests a new study in mice. The discovery could help surgeons avoid picking the most painful drugs or lead to alternative ways of relieving post-surgery pain. Pain is a by-product of many surgical procedures, but it was always assumed that the cause was the surgery itself. “It was never considered that the anaesthetic could contribute to the pain,” says Gerard Ahern of Georgetown University in Washington DC, who led the study. “The paradoxical finding is that the anaesthetic can worsen the severity of the damage done by the surgeon.” General anaesthetics were already known to cause some problems. Taken in the form of either an injection or gas, anaesthetics can cause irritation either at the site of the jab or in the airways, and surgeons often give patients a local anaesthetic first to reduce this side-effect. But it was a surprise that general anaesthetics can also worsen pain after surgery. Now, Ahern and his colleagues show that that these drugs can activate pain-sensing nerves throughout the body. When a patient is ‘put under’, the general anaesthetic activates a protein in the central nervous system called a GABA receptor. Switching these receptors off shuts down parts of the central nervous system, and the patient slips into unconsciousness. © 2008 Nature Publishing Group

Keyword: Pain & Touch
Link ID: 11735 - Posted: 06.24.2010

A passionate advocate for taking science to the masses, the Oxford professor has been showered with honours in Britain and Australia for her ability to make science relevant to broader society, and she generally does it with a beaming smile and a thousand words and ideas a minute. All of which makes it striking that Greenfield, one of Britain's leading brain scientists, is now expressing profound fears about the way new technology is changing our thought patterns and behaviour. "I don't want to sound like a techno-Luddite but we have to realise that something profound seems to be happening to the human brain," Greenfield explains in the central London office from where she runs the Royal Institution, a 209-year-old seat of scientific education and research. "And what really worries me is that we could be sleepwalking into a new world of technology without even considering what it is doing to our brains." The 57-year-old scientist may not want to sound alarmist or gloomy but her warning is about as serious as it gets. In a new book, ID: The Quest for Identity in the 21st Century, published by Sceptre, she says the challenge to our inner mental world is as big a crisis as the threat climate change poses to our outer world. Copyright 2008 News Limited.

Keyword: Emotions; Intelligence
Link ID: 11734 - Posted: 06.21.2008

By Nikhil Swaminathan Nearly a century after the discovery of strange star-shaped cells in the brain, scientists say they have finally begun to unravel their function. Researchers from the Massachusetts Institute of Technology report in Science that it appears astrocytes—named for their stellar form—provide nerve cells (neurons) with the energy they need to function and communicate with one another, by signaling blood to deliver the cell fuels glucose and oxygen to them. When astrocytes were first discovered, it was believed that they were bit players in the brain. But the new research indicates they may actually be major operators that, when out of whack, may help trigger mental disorders such as autism and schizophrenia. Study coauthor Mriganka Sur, a neuroscientist and head of MIT's Department of Brain and Cognitive Science, says his team saw astrocytes in action while examining brain activity in ferrets. Using technology called two-photon microscopy, Sur and his colleagues observed that astrocytes in the visual cortex (part of the brain responsible for vision) activated and blood flow increased to nerve cells just seconds after the neurons had fired or sent out signals. © 1996-2008 Scientific American Inc.

Keyword: Glia; Brain imaging
Link ID: 11733 - Posted: 06.24.2010

By Ann Gibbons Girls who eat more omega-3 fatty acids outsmart those who eat higher amounts of omega-6 fatty acids, according to new research. As a result of this and other studies, government dietary recommendations--especially those aimed at pregnant women--should emphasize fish over soy and corn oils, which are respectively high in these fatty acids, says Joseph Hibbeln, a psychiatrist and lipid biochemist at the National Institute on Alcohol Abuse and Alcoholism in Bethesda, Maryland. "We don't want the brain to be deficient in its critical nutrients during development." The omega-3 advantage was first hinted at in studies of distribution of body fat. Earlier this year, William Lassek, an epidemiologist at the University of Pittsburgh in Pennsylvania, and anthropologist Steven Gaulin of the University of California, Santa Barbara, reported that women who accumulated more fat on their hips than on their waists--and who, therefore, had low waist-hip ratios like many movie stars--had higher cognitive test scores, as did their children. They proposed that because the fat on the hips and thighs contains more omega-3s than belly fat does, these women were storing omega-3s critical for fetal and infant brain development--and boosting their own brainpower as they grew up. They also predicted that women who ate more omega-3s would perform better on cognitive tests than those who ate more omega-6s. To test this hypothesis, Lassek and Gaulin analyzed data on about 4000 girls and boys between the ages of 6 and 16. The children had participated in the Third National Health and Nutrition Examination Study, part of a U.S. project to assess the health and nutritional status of kids and adults. After the researchers controlled for the parents' income and education and for the children's age, race, number of siblings, and blood lead levels, they found that girls who ate more omega-3 scored significantly better on four cognitive tests, including an IQ test. © 2008 American Association for the Advancement of Science

Keyword: Intelligence; Obesity
Link ID: 11732 - Posted: 06.24.2010

Jennifer Viegas -- What goes on in an ape's mind might be more similar to our own way of thinking than previously realized, suggests a new study that found chimpanzees and orangutans plan for their futures. Since this skill also entails forethought involving self-control and mental time travel, the findings point to a complex "inner mental world" possessed by apes, including gorillas, which were studied in trials before the official research began. "When humans shut their eyes, a new vivid world takes hold," co-author Mathias Osvath told Discovery News. "This mental world with its first-person perspective has been suggested to be unique to humans," added Osvath of Lunds University Cognitive Science in Sweden. "It is arguably impossible to plan like the apes do without having an inner world of some sort. (Our results) strongly imply a consciousness that many think is restricted to the human domain." For the study, published in Animal Cognition, he and colleague Helena Osvath first showed two female chimps, Linda and Maria Magdalena, along with a male orangutan named Naong, how to sip a yummy fruit soup using a straw-like hose. The researchers next presented their furry test subjects with a favorite fruit -- a grape -- and the hose, which the animals could save and use to sip soup later. The apes exercised self-control by foregoing the immediate grape reward. They instead chose the hose and patiently waited for the bigger food payoff. © 2008 Discovery Communications, LLC.

Keyword: Evolution; Intelligence
Link ID: 11731 - Posted: 06.24.2010

Jo Marchant Why do donkeys snooze for just three hours a day, while hairy armadillos are knocked out for more than 20? Biologists have struggled to find any satisfactory explanation for the bewildering variation in how much different mammals sleep. However, new studies that take evolutionary relatedness into account promise to revolutionise the field. In particular, one large study suggests that REM (rapid eye movement) sleep – during which the brain is highly active – may play a key role in intelligence. Lab studies in humans already suggest that REM sleep is important for cognitive abilities such as consolidating memories – a good night's sleep – with plenty in the REM phase – can improve people's ability to remember what they have learned in the day by about 15%. In other species, the evidence is less clear cut. If REM sleep helps learning, then mammals with more developed brains should presumably need more of it, but in the past no such relationship has been found. One of the few biological functions that has been found to correlate with sleep patterns is metabolic rate. Animals with a relatively high metabolic rate for their body size seem to need more non-REM sleep, suggesting that catching extra Zs simply helps them conserve precious energy. © Copyright Reed Business Information Ltd

Keyword: Sleep; Intelligence
Link ID: 11730 - Posted: 06.24.2010