Alison Abbott Electrodes implanted into the brain of a patient undergoing an experimental treatment for obesity have surprisingly improved his memory skills. The startling and unexpected effects — reported in Annals of Neurology 1 — have prompted the Canadian team of neurologists to launch a new deep-brain stimulation (DBS) trial in patients with early Alzheimer’s disease. Three patients have already had electrodes implanted, says neurosurgeon Andres Lozano from the University of Toronto's Toronto Western Research Institute. “The surgery seems safe and the results are promising,” he says. During DBS, a hair-thin electrode with four contact points is placed in a very precise area of the brain. Each contact can be stimulated individually with different frequencies of electric current — or switched off — by remote control. The tiny currents are intended to activate specific neural circuits in the brain that under-perform in particular disorders. The procedure is most often used to treat Parkinson’s disease but, in the past few years, neurosurgeons have been experimenting with treating psychiatric disorders including depression and obsessive-compulsive disorder. © 2008 Nature Publishing Group

Keyword: Learning & Memory
Link ID: 11257 - Posted: 06.24.2010

Andrew W. McCollough & Edward K. Vogel Anyone who has tried to find an urgent email amid masses of advertisements for dubious stock opportunities and sexual enhancement drugs understands the critical importance of being able to filter out distracting information. That important email may be in there but it is lost among irrelevant clutter. And while the capacity of our email inbox is limited only by disc space, our mental 'inbox' of working memory is much more constrained. In fact, several decades of research have indicated that our capacity to hold information “in mind” for immediate use is limited to a mere three or four items. Moreover, just as people vary in height and eye color, we also vary in the capacity of this memory inbox. Interestingly, these differences in working memory capacity are strongly predictive of a person’s ability to perform abstract reasoning, mathematics, and other forms of complex problem solving. This relationship between memory capacity and fluid intelligence has motivated many scientists to try to understand why and how people differ in this important cognitive ability. There are at least two primary explanations for this severe limitation in working memory capacity. First, it could be that working memory capacity is essentially determined by storage space, and that some people have larger "hard drives" than others do. The alternative explanation is that capacity depends not on the amount of storage space but on how efficiently that space is used. Thus high-capacity individuals might simply be better at keeping irrelevant information out of mind, whereas low capacity individuals may allow more irrelevant information to clutter up the mental inbox. High-capacity individuals may just have better spam filters. © 1995-2007 Scientific American Inc

Keyword: Learning & Memory; Attention
Link ID: 11256 - Posted: 06.24.2010

United States researchers suggest long-ago lead exposure can make an aging person's brain work as if it's five years older than it really is. "We're trying to offer a caution that a portion of what has been called normal aging might in fact be due to ubiquitous environmental exposures like lead," says Dr. Brian Schwartz of Johns Hopkins University, a leader in the study of lead's delayed effects. The notion of long-delayed effects is familiar; tobacco and asbestos, for example, can lead to cancer. But in recent years, scientists are coming to appreciate that exposure to other pollutants in early life also may promote disease much later on. "It's an emerging area" for research, said Dr. Philip Landrigan of the Mount Sinai School of Medicine in New York. It certainly makes sense that if a substance destroys brain cells in early life, the brain may cope by drawing on its reserve capacity until it loses still more cells with aging, he said. Only then would symptoms like forgetfulness or tremors appear. Studying delayed effects in people is difficult because they generally must be followed for a long time. Research with lead is easier because scientists can measure the amount that has accumulated in the shinbone over decades and get a read on how much lead a person has been exposed to in the past. © CBC 2008

Keyword: Neurotoxins; Alzheimers
Link ID: 11255 - Posted: 06.24.2010

Life may begin at 40, but research suggests that 44 is the age at which we are most vulnerable to depression. Data analysis on two million people from 80 countries found a remarkably consistent pattern around the world. The risk of depression was lowest in younger and older people, with the middle-aged years associated with the highest risk for both men and women. The study, by the University of Warwick and Dartmouth College in the US, will feature in Social Science & Medicine. The only country which recorded a significant gender difference was the US, where unhappiness reached a peak around the age of 40 for women, and 50 for men. Previous research has suggested that the risk of unhappiness and depression stays relatively constant throughout life. However, the latest finding - of a peak risk in middle age - was consistent around the globe, and in all types of people. Researcher Professor Andrew Oswald, an economist at the University of Warwick, said: "It happens to men and women, to single and married people, to rich and poor, and to those with and without children." He said the reason why middle age was a universally vulnerable time was unclear. However, he said: "One possibility is that individuals learn to adapt to their strengths and weaknesses, and in mid-life quell their infeasible aspirations. Another possibility is that a kind of comparison process is at work in which people have seen similar-aged peers die and value more their own remaining years. Perhaps people somehow learn to count their blessings." (C)BBC

Keyword: Depression
Link ID: 11253 - Posted: 01.29.2008

By JANE E. BRODY When a woman complains of genital pain so severe that it makes sexual intercourse all but impossible, her partner may jump to the conclusion that she has a phobia about sex. But what if that same woman also experiences excruciating pain when trying to insert a tampon, undergo a pelvic exam, wear a pair of jeans, ride a bicycle or go jogging? Can phobia explain all those problems? Not very likely. In fact, studies have shown that sexual phobias are rarely the explanation for a condition known as vulvodynia, a chronic discomfort of the vulva that can result in searing or shooting pain when any amount of pressure is placed on the sensitized tissues. Some women compare the feeling to acid being poured on an open wound. The problem can last months, years or a lifetime. Worse, doctors often misdiagnose it or treat it inappropriately, if at all. For decades, women suffering from vulvodynia have been told that nothing seems to be wrong with them — nothing, that is, that the examining physician can discern — or that the condition may be real but that nothing can be done. Christin Veasley of Providence, R.I., said that vulvodynia, which was diagnosed at age 18 during her freshman year at college, made it impossible for her to sit long enough to finish a midterm exam. Her doctor said there was no help for her condition. Copyright 2008 The New York Times Company

Keyword: Pain & Touch; Sexual Behavior
Link ID: 11252 - Posted: 06.24.2010

By HENRY FOUNTAIN Researchers who study the brain know that it’s far from an immutable object. “It’s much more plastic than most people think,” said Giulio Tononi, a psychiatrist at the University of Wisconsin. “It’s changing all the time.” One area of change is the synapses, the connections between neurons, which are altered as the brain receives stimuli. “What happens when you’re awake is you produce an overall strengthening of synapses,” Dr. Tononi said. “That’s good, because that’s how you learn.” But that is unsustainable in the long run, because stronger synapses require more energy and material, and there’s a limit to how much of both is available. “It’s as if in the morning you start with a V-6 engine,” he said, “and in the evening you find yourself idling, but you’re running a V-8.” Stronger synapses are also bigger, but the brain cannot grow bigger or denser. “If you strengthen synapses because you learn, soon you’d reach a point where you can’t learn further,” he added. So Dr. Tononi and a colleague, Chiara Cirelli, have hypothesized that during sleep, the synapses weaken. The downscaling is across the board, so that the synapses’ relative strength is maintained. Those that have been used (those involved in learning) stay stronger than those that haven’t. Copyright 2008 The New York Times Company

Keyword: Sleep; Learning & Memory
Link ID: 11251 - Posted: 06.24.2010

By Michael Balter Don't take that hammer for granted. Using tools may seem like second nature, but only a few animals can master the coordination and mental sophistication required. So how did primates learn to use tools in the first place? A new study in monkeys suggests that the brain's trick is to treat tools as just another body part. Primates, with their four flexible fingers and opposable thumbs, have a highly evolved ability to grasp and manipulate objects. Previous research has shown that many of these actions are controlled by an area of the brain called F5. As the hand opens and closes to grasp an object, neurons in area F5 fire in a predictable sequence. In the parlance of neuroscientists, the neurons are "coded" to control the hand movements. When a primate learns to use a tool, its brain must code neurons not only to move the hand but also to make the tool manipulate an object, a much more cognitively complex task. To investigate how the brain performs this sleight of hand, a team led by neuroscientist Giacomo Rizzolatti of the University of Parma in Italy recorded brain activity in two macaque monkeys. Each was trained for 6 to 8 months to grasp items of food with pliers. The team documented the activity of 113 neurons in F5 and in a brain area called F1, which has also been implicated in the manipulation of objects. The researchers first established the brain's firing sequence when the monkeys grasped only with their hands. The experiment was then repeated while the monkeys used normal pliers that required first opening the hand and then closing it to grasp the food. The same neurons fired in the same order. Remarkably, the same neurons also fired, in the same order, when the monkeys used "reverse pliers" that required them to close their fingers first and then open them to take the food, the team reports online today in the Proceedings of the National Academy of Sciences. © 2008 American Association for the Advancement of Science

Keyword: Miscellaneous
Link ID: 11250 - Posted: 06.24.2010

Jennifer Viegas -- Feline defensive rage, the aggressive cat behavior that recently led to the death of a California zoo visitor by a tiger that felt threatened, is comparable to human rage, both in the way that it emerges and unleashes in the brain, suggests a new study. Because scientists are gaining a better understanding of the mammalian brain's recipe for rage, violent behavior in humans and other mammals may one day be quelled with improved drug therapies. For cats, such a drug could prevent the hissing, back arching, ear retraction, claw extensions and fur standing-on-end that are typical indicators of feline defensive rage. In humans, related anger reveals itself with road rage, an impulsive form of anger that involves little or no thought. "In road rage, the person never thinks about what he is doing but just acts in the way he does because he feels that he has been threatened by someone else and the impulsive behavior represents a way by which he can protect himself from such a threat," co-author Allan Siegel told Discovery News. "In reality, his actions are usually much more dangerous to him than to the person whom he perceived cut him off on the road," added Siegel, a professor in the Department of Neurology & Neurosciences at New Jersey Medical School in Newark. © 2008 Discovery Communications,

Keyword: Emotions; Evolution
Link ID: 11249 - Posted: 06.24.2010

Debora MacKenzie Chameleons are famed for changing colour to blend in with their surroundings and hide from predators – but new research on chameleons in their native habitat shows some of their colour changes evolved for exactly the opposite purpose – attracting attention. African dwarf chameleons live in habitats in southern Africa ranging from grassland to rainforest. They engage in complex social signalling, with bright colour changes along their flanks used by females to signal interest or rejection to males, and by males to signal aggression or submission to other males, and interest towards females. Males even square off in rapid-fire, colourful signalling duels. "Chameleons use colour change for camouflage and communication, but we don't know why some species change colour much more than others", says Devi Stuart-Fox of the University of Melbourne in Australia. She and colleague Adnan Moussalli reasoned that if these differences evolved solely to enable the chameleon to match itself to its surroundings, chameleons living in backgrounds that vary a lot in colour should produce a wider palette, whereas chameleons in less colourful environments should not. © Copyright Reed Business Information Ltd.

Keyword: Animal Communication
Link ID: 11248 - Posted: 06.24.2010

Andy Coghlan An internal clock hidden in human skin cells could reveal whether your body clock is out of sync with your lifestyle, say researchers. Steven Brown of the University of Zurich in Switzerland and his colleagues knew that the brain’s circadian clock causes a gene called Bmal1 to be more active in the body’s other cells during the daytime. To find out how closely matched this activity was, they used a virus to equip skin cells taken from 11 early-rising people dubbed "larks" and 17 late-rising "owls" with a firefly gene that would produce a visible glow whenever Bmal1 was active. “The result is light coming out of the cell in a 24-hour rhythm,” says Brown. By monitoring the times when the cells glowed, they demonstrated that skin cells showed the same sleep-wake patterns as those reported in questionnaires by at least half the donors. There were discrepancies too, however, most notably in three individuals with seasonal affective disorder. This suggested that skin biopsies might be useful for diagnosing sleep and circadian disorders. © Copyright Reed Business Information Ltd

Keyword: Biological Rhythms
Link ID: 11247 - Posted: 06.24.2010

Anna Petherick Researchers have added to the list of biological curiosities about mole-rats: the animals do not feel all types of pain. The discovery could eventually help humans who are battling chronic discomfort. African naked mole-rats (Heterocephalus glaber ) are unusual creatures — they are cold-blooded mammals, have a long lifespan, and live in co-operative societies of hundreds of individuals in a manner more typical of bees and wasps than moles or rats. The animals react normally to the mechanical pain caused by pinching and prodding, but are insensitive to a suite of other normally nasty stimuli, according to Thomas Park of the University of Illinois at Chicago, Gary Lewin at the Max-Delbrück Center for Molecular Medicine in Berlin, Germany, and their colleagues. Those stimuli include acid and capsaicin, the ingredient in chilli peppers that causes a burning sensation in many animals. These mole-rats are also odd in that their skin, when inflamed, does not become hypersensitive when exposed to unpleasantly hot objects, even though they react to excessive heat in the same way that other mammals do, the researchers report in PloS Biology 1. © 2008 Nature Publishing Group

Keyword: Pain & Touch; Evolution
Link ID: 11246 - Posted: 06.24.2010

If you need another reason to keep that New Year's resolution to quit smoking, here it is: a U.S. researcher says he has discovered smoking can disable a gene that protects against premature aging. The gene, SIRT1 is one of a group that regulates chronic inflammation, cancer and aging. When it is highly active, or over-expressed in mice, worms and fruit flies, their lifespans are greatly increased. Recent studies also show that SIRT1 helps ease the negative effects of stress, cell death and other processes involved in premature aging. According to University of Rochester associate professor of Environmental Medicine, Irfan Rahman, the toxins in cigarette smoke can decrease production of SIRT1 in the lungs. His research was published in two separate studies, in the American Journal of Respiratory Critical Care Medicine, appearing online Jan. 3, 2008, and in the American Journal of Physiology, appearing Dec. 27, 2007. Rahman has spent years studying how the 4,700 toxic chemical compounds in cigarettes assault lung tissue. © CBC 2008

Keyword: Drug Abuse
Link ID: 11245 - Posted: 06.24.2010

ST. PAUL, Minn. – Contrary to some reports, taking statins, which are cholesterol-lowering drugs, offers no protection against Alzheimer’s disease, according to research published in the January 16, 2008, online issue of Neurology®, the medical journal of the American Academy of Neurology. The study involved 929 Catholic clergy members who were an average of 75 years old, free of dementia at the beginning of the study and enrolled in the Religious Orders Study, an ongoing study of aging and Alzheimer’s disease. All of the participants agreed to a brain autopsy at the time of their death and underwent annual cognitive tests for up to 12 years. At the beginning of the study, 119 people were taking a statin. During the 12-year follow-up period, 191 people developed Alzheimer’s disease, of whom 16 used statins at the start of the study. “Some studies have suggested people taking cholesterol-lowering drugs are less likely to have Alzheimer’s disease, but our longitudinal findings found no relation between statin use and Alzheimer’s,” said study author Zoe Arvanitakis, MD, MS, Associate Professor of the Department of Neurological Sciences at Rush University Medical Center in Chicago and member of the American Academy of Neurology. “The study also found no association between taking statins and a slower cognitive decline among older people.”

Keyword: Alzheimers
Link ID: 11244 - Posted: 06.24.2010

By Nikhil Swaminathan Aha! Eureka! Bingo! "By George, I think she's got it!" Everyone knows what it's like to finally figure out a seemingly impossible problem. But what on Earth is happening in the brain while we're driving toward mental pay dirt? Researchers eager to find out have long been on the hunt, knowing that such information could one day provide priceless clues in uncovering and fixing faulty neural systems believed to be behind some mental illnesses and learning disabilities. Researchers at Goldsmiths, University of London report in the journal PLoS ONE that they monitored action in the brains of 21 volunteers with electroencephalography (EEG) as they tackled verbal problems in an attempt to uncover what goes through the mind—literally—in order to observe what happens in the brain during an "aha!" moment of problem solving. "This insight is at the core of human intelligence … this is a key cognitive function that the human can boast to have," says Joydeep Bhattacharya, an assistant professor in Goldsmiths's psychology department. "We're interested [in finding out] whether—there is a sudden change that takes place or something that changes gradually [that] we're not consciously aware of," he says. The researchers believed they could pin down brain signals that would enable them to predict whether a person could solve a particular problem or not. © 1996-2007 Scientific American Inc.

Keyword: Attention; Intelligence
Link ID: 11243 - Posted: 06.24.2010

Shauna Rempel Name: Jennifer Gutsell Program: First-year master's student in psychology at the University of Toronto. Research: Prejudice and the Mirror Neuron System. The goal: "I'm looking for the reason why people are prejudiced," says Gutsell. While it's understood that people are capable of prejudice, and that they are more likely to exhibit bias toward people who are different from themselves, little is known about how the brain contributes to these feelings. The mirror neuron system: This recently discovered system in the brain may have something to do with prejudice. The mirror neuron system is so named because researchers think it explains why humans and some animals "mirror" the behaviour that they see in others. This system, which is linked to feelings of empathy, may also offer a clue as to why prejudice evolved – by looking at situations where people are less empathetic to some people and more empathetic to others. "The mirror neuron system is less responsive to people we don't like," says Gutsell. In other words, you're less likely to shed a tear if you see your enemy sobbing than if you saw your best friend crying. Research on prejudice shows that people tend to show bias toward ethnic and racial groups that are not our own, and Gutsell decided to see if the mirror neuron system was involved. © Copyright Toronto Star 1996-2008

Keyword: Emotions
Link ID: 11242 - Posted: 06.24.2010

Premature babies who receive morphine may grow up to be more sensitive to pain, a study on rats suggests. US researchers found rodents given the drug just after birth later needed higher doses of morphine to kill pain than counterparts in a placebo group. Morphine is a standard part of care for premature babies, who may need hundreds of painful treatments and tests. The study reported in New Scientist, raises questions, if not answers, about the practice, experts say. Researchers at the University of South Carolina treated newborn rats with morphine injections for the first nine days of life and tested their pain responses a few weeks later. Rats are born so immature that their early development is comparable with that of a premature baby. After nearly six weeks, broadly equivalent to a human becoming a teenager, the morphine rat appeared to be more sensitive to be pain than the rat given the placebo. For instance it withdrew it paws more readily when these were heated with a lamp, and when pain was induced appeared to need more morphine to quell it. About 3% of babies in the US and UK are born so prematurely they need treatments which in turn are believed to require pain relief. Their pain is judged on their physical response, and the drug is administered accordingly. (C)BBC

Keyword: Pain & Touch; Development of the Brain
Link ID: 11241 - Posted: 01.25.2008

The Democratic Republic of Congo's Virunga National Park and the surrounding Virunga volcanoes region are home to more than half of the world's population of mountain gorillas. To ensure the long-term survival of this threatened species, teams of rangers monitor and patrol the park's Gorilla Sector. Two of the rangers, Diddy and Innocent, have been keeping a weekly diary for the BBC News website that offers an insight into life on the frontline of conservation. Here, they also share video footage that they have been recording over the past few months. MEET THE GORILLAS Here is footage of some of the park's gorilla groups, known as "families", which are named after the dominant male or "silverback". Innocent, head of gorilla monitoring, is able to recognise every gorilla within the sector. Each animal has a unique "nose print" that enables rangers to tell them apart. (C)BBC

Keyword: Animal Communication; Language
Link ID: 11240 - Posted: 01.25.2008

David Perlman The human mind does strange and wondrous things: Its 100 billion nerve cells packed into a single, lumpy gray organ called the brain can think faster than a computer, ponder the mysteries of life with excruciating slowness, control every movement of the body and command it to fight, flee or stand its ground in defiance. Now, at San Francisco's Exploratorium at the Palace of Fine Arts in the Marina, a team of neuroscientists, artists, mechanics and builders has created a varied collection of exhibits - many weird as can be - that allow visitors to watch their own minds at work. The interactive exhibits will have visitors use their minds for speed-thinking competitions, to catch a liar in a simulated poker game, to conceal their thoughts when they themselves lie, or to react to emotional conflicts: One, for example encourages visitors to drink from a water fountain that's actually a toilet. A major feature of the show is the first public showing ever of a black-and-white movie that Paul Ekman, the famed UCSF psychologist, made 40 years ago in New Guinea to prove that Charles Darwin was right and modern anthropologists like famed Margaret Mead were wrong when they argued that facial expressions of human emotions differed among people in different cultures. Darwin published his seminal book, "The Expression of the Emotions in Man and Animals," in 1872 and argued that human facial expressions mirrored emotions regardless of the culture in which a person lived. They were part of humanity's evolutionary endowment, Darwin maintained. © 2008 Hearst Communications Inc

Keyword: Emotions; Evolution
Link ID: 11239 - Posted: 06.24.2010

By Nikhil Swaminathan Blood racing through a brain region's web of vessels is a sign that nerve cells in that locale have kicked into action. The blood rushes to active areas to supply firing neurons with the oxygen and glucose they need for energy. It is this blood flow, which can last up to a minute, that scientists track in functional magnetic resonance imaging (fMRI) to determine which brain areas are responding to different stimuli. But a new theory could pave the way for a reinterpretation of fMRI images, elevating their measurements to the evaluation of actual neuronal processing rather than the subsequent blood flow that indirectly indicates it, and thereby enhancing the fMRI's usefulness in diagnosing neurological problems. Christopher Moore, an assistant neuroscience professor at the Massachusetts Institute of Technology's McGovern Institute for Brain Research, detailed his hypothesis in a recent article published in the Journal of Neurophysiology. In essence, it suggests blood's role in the cortex (a key brain processing center), specifically, is more than just bringing nutrients to the cell, it can also alter the activity of local neuronal circuits. For instance, in experiments in his lab, Moore has seen that there is more blood flow can arrive in an area that processes information from a presented stimulus to a certain sense (e.g. touch, visual, auditory) prior to the appearance of the stimulus, implying that the flow can prime a circuit for activity, as well. © 1996-2007 Scientific American Inc.

Keyword: Brain imaging; Alzheimers
Link ID: 11238 - Posted: 06.24.2010

Mason Inman Passport and ID card photos could be more effective if they were averages of several snapshots, say researchers who have shown that approach allows facial recognition software to spot familiar faces as well humans do. Psychologists Rob Jenkins and Mike Burton of the University of Glasgow, UK, were inspired by studying how we recognize familiar faces. They found humans are much better at recognizing averaged faces than if shown an individual photo. The duo argues that as we see a person from different angles and in varied lighting, we build a mental image of their face that averages out all those experiences. They went on to show that averaging multiple photos of a person can also help facial recognition software work better. The researchers plugged individual photos of male celebrities into an online genealogy service, MyHeritage.com. The website allows people to compare their photos against a large database of celebrity images to see which famous people they most closely resemble. The site is powered by a facial recognition program called FaceVACS. It is one of the best available, according to a 2006 test by the US National Institute of Standards and Technology. © Copyright Reed Business Information Ltd.

Keyword: Vision
Link ID: 11237 - Posted: 06.24.2010