By Larry Greenemeier It sounds like something out of an Edgar Allen Poe tale of horror. A man becomes agitated by strange sounds only to find that they are emanating from inside his own body—his heart, his pulse, the very movement of his eyes in their sockets. Yet superior canal dehiscence syndrome (SCDS) is a very real affliction caused by a small hole in the bone covering part of the inner ear. Such a breach results in distortion of hearing and, often, impaired balance. The human ear consists of three parts. The outer ear includes the ear lobe and external auditory canal, which funnels sound waves toward the eardrum (or tympanic membrane) allowing it to vibrate. The middle ear converts sound waves that vibrate the eardrum into mechanical vibrations for the cochlea, the hearing part of the inner ear. This area, however, also includes of a system of three fluid-filled semicircular canals in each ear—superior, posterior and horizontal—responsible for giving the brain information about angular motion of the head. SCDS can occur when some part of the bone protecting the superior semicircular canal is missing. Whereas it is difficult to know exactly how prevalent SCDS is, several reported cases define how it impacts the lives of those suffering from the disorder. Stephen Mabbutt, a 57-year-old Englishman who suffered from SCDS for six years, described "hearing his eyes scratching like sandpaper every time they moved in their sockets." He returned to work earlier this month after successful surgery to plug a pin-size hole in the bone covering the semicircular superior canal in one of his ears. Toby Spencer, a 41-year-old IT professional from Skowhegan, Maine, described similar symptoms as Mabbutt as well as the feeling that loud noises made him feel as though he was losing his balance. Spencer had surgery in April to correct the problem. © 2011 Scientific American

Keyword: Hearing
Link ID: 15761 - Posted: 09.03.2011

Sandrine Ceurstemont, video producer Watch a line sweep across a screen and its direction of motion is easily perceived. But when the same line is viewed through an opening, it appears to change course (see animation above). The perceived motion seems to be determined by the shape of the aperture and the line's orientation, rather than its true behaviour, so why do we experience this effect? According to Dale Purves and his team from Duke University, North Carolina, we're tricked because our brain assumes that the line in the video is a 2D projection originating from a linear object moving in 3D space. Since it's impossible to determine the real world source of the projected line, we rely on a mental model formed by accumulated experience and presume that the object is moving in that direction. Purves and his team tested the theory by using a variety of 3D sources and examining the linear motion produced through different shaped openings. They confirmed that, in each case, the motion we perceive represents the most common scenario. Previous research has suggested that the phenomenon is based on how the moving object interacts with the boundary of the opening. But this doesn't hold up for every type of aperture shape. © Copyright Reed Business Information Ltd.

Keyword: Vision
Link ID: 15760 - Posted: 09.03.2011

Jessica Hamzelou, reporter An Italian woman is the latest person to have a murder sentence reduced on the grounds that abnormalities in her brain, and genes, could explain her behaviour. Neuroimaging is being used more and more in courtrooms across the globe, but is it really possible to judge how responsible a person is for their actions by looking at a picture of their brain? Two years ago, Stefania Albertani was convicted of murdering her own sister. Albertani is widely reported as having killed her sibling by force-feeding her psychotropic drugs, before setting fire to her corpse. Months later, she went after her parents. After being found guilty of the killing, Albertani was initially sentenced to lifetime imprisonment. Appeals by neuroscientists and geneticists, however, have controversially succeeded in reducing the sentence to 20 years - a first for the Italian courts. The scientists involved pointed out that a scan of Albertani's brain looked different to those of ten healthy women. According to the journal Nature, the team claimed that her behaviour could be explained by alterations in the grey matter of two key brain regions: the anterior cingulate gyrus - involved in inhibiting behaviour - and the insula, which has been linked to aggression. © Copyright Reed Business Information Ltd.

Keyword: Brain imaging; Aggression
Link ID: 15759 - Posted: 09.03.2011

by Moheb Costandi The brain waves associated with sleep and dreaming could be helpful for distinguishing between people in a persistent vegetative state and those who are minimally conscious – a distinction that could seal the fate of the individual. The minimally conscious state, persistent vegetative state and coma are all disorders of consciousness caused by severe brain damage. Minimally conscious individuals tend to have better outcomes than vegetative individuals, but distinguishing between them is difficult and misdiagnosis is common. Getting it wrong can sometimes mean that a person who might otherwise recover has their life-support machine switched off. Earlier this year, Mélanie Boly at the University of Liège in Belgium and colleagues reported that minimally conscious patients respond to sounds, whereas vegetative patients do not. The team has now found more evidence that some brain function is preserved in the minimally conscious state. The team used electroencephalography (EEG) to record the electrical activity of the brain in six minimally conscious and five vegetative people while they slept. These individuals had been diagnosed using traditional tests for reflex movements and responses to sounds and other stimuli. Five of the six minimally conscious people exhibited brain-wave patterns that are typical of normal sleep, alternating between rapid eye movement (REM) and non-REM, or "slow-wave", sleep during the night. © Copyright Reed Business Information Ltd.

Keyword: Sleep; Attention
Link ID: 15758 - Posted: 09.03.2011

by Michael Marshall WHEN wondering about the origins of our brain, don't look to Homo sapiens, chimpanzees, fish or even wormsMovie Camera. Many key components first appeared in single-celled organisms, long before animals, brains and even nerve cells existed. Dirk Fasshauer of the University of Lausanne, Switzerland, and colleagues were studying a pair of essential neural proteins called Munc18/syntaxin1 when they decided to look for them in very simple, single-celled organisms. Choanoflagellates are aquatic organisms found in oceans and rivers around the globe. Being a single cell, they do not have nerves, yet the team found both proteins in the choanoflagellate Monosiga brevicollis, and the interaction between the two was the same as in neurons (Proceedings of the National Academy of Sciences, DOI: 10.1073/pnas.1106189108). These proteins are found in every nerve cell and control the release of the chemicals which neurons use to talk to each other, called neurotransmitters. The finding is intriguing on its own, but much more significant when combined with a growing body of evidence that essential brain components evolved in choanoflagellates before multicellular life appeared. In 2008, Xinjiang Cai of Duke University in Durham, North Carolina, discovered that M. brevicollis has the same calcium channels in its cells as those used by neurons (Molecular Biology and Evolution, DOI: 10.1093/molbev/msn077). Then, in 2010, it emerged that M. brevicollis also has several proteins that neurons use to process signals from their neighbours (BMC Evolutionary Biology, DOI: 10.1186/1471-2148-10-34). © Copyright Reed Business Information Ltd

Keyword: Evolution
Link ID: 15757 - Posted: 09.03.2011

Tiny clots in the brain may be the cause of some signs of old age such as stooped posture and restricted movement, say US scientists. Researchers examining the brains of 418 deceased patients found damaged blood vessels in 29% of them which would not have been picked up by normal scans. They said higher levels of damage were linked to more limited movement. The researchers, writing in the journal Stroke, said declining mobility should not be accepted as normal ageing. Mild symptoms of Parkinson's disease - such as slow movement, rigidity, tremors and posture - increase with age and are thought to affect up to half of people by the age of 85. A team of scientists at the Rush University Medical Center, in Chicago, carried out autopsies on the brains of nuns and priests who were taking part in the Religious Order Study. The brains were examined under a microscope for signs of damage which would be invisible to normal brain scans. They found 29% of patients with no previously detected sign of stroke had clotted or narrowed blood vessels. BBC © 2011

Keyword: Stroke; Alzheimers
Link ID: 15756 - Posted: 09.03.2011

by Alva Noë Our attitudes to addiction conceal a whole philosophy. And this goes for our neuroscientific theories as well. It is commonplace for scientists theorizing about the brain to take for granted that, well, we are our brains. We seem to experience other people, surrounding environs, events, actions, things of value and importance. Yes, but, from a scientific point of view, this is all an illusion. Our brains have evolved to produce this robust confabulation! After all, what is the world to us, really? At best: patterns of sensory rubbing. And what are our thoughts, feelings, our aspirations, our actions, our loves and our pleasures? What are our friends? What are wars? These are nothing but neuro-chemical fluctuations in the selves we really are. According to the new experts, everything is a phenomenon — one might say disease — of the brain. Why does a baby love his mother? It's the opioids in the mother's milk, of course! And what is that love anyway but a neurotransmitter-induced alteration of activity in our neural circuits! And so it should come as no surprise that the experts also think that addiction is a disease of the brain. What else could it be? In fact, from the standpoint of the new philosopher-neuroscientists, there is almost something ideologically pristine or kosher about the addict's world view. Most of us non-addicts, we slog and toil, trying to make careers, support families, earn money, afford leisure — we work hard to make worlds for ourselves that can in turn provide us with satisfaction and meaning. We make choices. Copyright 2011 NPR

Keyword: Drug Abuse
Link ID: 15755 - Posted: 09.03.2011

By Pallab Ghosh Science correspondent, BBC News The world's first clinical trial of brain stem cells to treat strokes is set to move to its next phase. An independent assessment of the first three patients to have had stem cells injected into their brain at Glasgow's Southern General Hospital has concluded it has had no adverse effect. The assessment paves the way for the therapy to be tested on more patients to find a new treatment for stroke. The hope is that the stem cells will help to repair damaged brain tissue. The trial is being led by Prof Keith Muir of Glasgow University. He told BBC News that he was pleased with the results so far. "We need to be assured of safety before we can progress to trying to test the effects of this therapy. Because this is the first time this type of cell therapy has been used in humans, it's vitally important that we determine that it's safe to proceed - so at the present time we have the clearance to proceed to the next higher dose of cells." An elderly man was the first person in the world to receive this treatment last year. Since then it has been tried out on two more patients. The patients have received very low doses of stem cells in trials designed to test the safety of the procedure. BBC © 2011

Keyword: Stroke; Stem Cells
Link ID: 15754 - Posted: 09.01.2011

by Wendy Zukerman Ever struggled to get an annoyingly catchy tune out of your head? Blame your right anterior temporal lobe – a thumb-shaped region of the brain just behind the right ear. Damage to this brain region in people with some forms of dementia is what leaves them unable to recognise famous melodies, a study suggests. Olivier Piguet and colleagues at Neuroscience Research Australia in Sydney wanted to understand why people with Alzheimer's disease have difficulties with memory, yet can remember information if it is sung to them. One clue comes from a 2006 study which found that the right anterior temporal lobe is responsible for the way we understand words and concepts. To find out more, Piguet asked 27 volunteers with dementia to listen to pairs of tunes. Fourteen volunteers had Alzheimer's and 13 had semantic dementia (SD), a condition in which people can speak fluently but lose the ability to remember the names of objects, people and abstract concepts. Twenty healthy volunteers also participated. Piguet suspected that people with SD would have more trouble than those with Alzheimer's when it came to identifying tunes. If so, he could pinpoint the area of the brain responsible for processing music by comparing which brain regions were damaged in the two groups. © Copyright Reed Business Information Ltd.

Keyword: Alzheimers; Hearing
Link ID: 15753 - Posted: 09.01.2011

Matt Kaplan The discovery of stone axes in the same sediment layer as cruder tools indicates that hominins with differing tool-making technologies may have coexisted. The axes, found in Kenya by Christopher Lepre, a palaeontologist at Columbia University in New York, and his team are estimated to be around 1.76 million years old. That's 350,000 years older than any other complex tools yet discovered. The finding, described today in Nature1, includes another important discovery: the hand axes, usually associated with the emergence around 1.5 million years ago of Homo erectus as the dominant hominin species, were found alongside primitive chopping tools that had already been in use for at least a million years. "This supports the idea that the two earliest stone-tool manufacturing techniques and traditions were, at least sometimes, utilized contemporaneously," says palaeoanthropologist Briana Pobiner at the Smithsonian Institution in Washington DC. Chip off the old block The hand axes, which have a distinctive, carefully made oval shape, are part of the Acheulian technology — those tools thought to have been developed around 1.6 million years ago. The more primitive tools, typically chunks of stone with crudely-chipped edges, belong to the earlier Oldowan toolkit. Because H. erectus is often associated with Acheulian tools, Lepre and his colleagues suggest that the hand axes they found might have been made by H. erectus, and the Oldowan tools by the less cognitively-capable Homo habilis. © 2011 Nature Publishing Group,

Keyword: Evolution
Link ID: 15752 - Posted: 09.01.2011

Kerri Smith The experiment helped to change John-Dylan Haynes's outlook on life. In 2007, Haynes, a neuroscientist at the Bernstein Center for Computational Neuroscience in Berlin, put people into a brain scanner in which a display screen flashed a succession of random letters1. He told them to press a button with either their right or left index fingers whenever they felt the urge, and to remember the letter that was showing on the screen when they made the decision. The experiment used functional magnetic resonance imaging (fMRI) to reveal brain activity in real time as the volunteers chose to use their right or left hands. The results were quite a surprise. "The first thought we had was 'we have to check if this is real'," says Haynes. "We came up with more sanity checks than I've ever seen in any other study before." The conscious decision to push the button was made about a second before the actual act, but the team discovered that a pattern of brain activity seemed to predict that decision by as many as seven seconds. Long before the subjects were even aware of making a choice, it seems, their brains had already decided. As humans, we like to think that our decisions are under our conscious control — that we have free will. Philosophers have debated that concept for centuries, and now Haynes and other experimental neuroscientists are raising a new challenge. They argue that consciousness of a decision may be a mere biochemical afterthought, with no influence whatsoever on a person's actions. According to this logic, they say, free will is an illusion. "We feel we choose, but we don't," says Patrick Haggard, a neuroscientist at University College London. © 2011 Nature Publishing Group,

Keyword: Attention
Link ID: 15751 - Posted: 09.01.2011

By ANAHAD O'CONNOR Earlier studies have tied chronic sleep disorders and low levels of sleep to greater risks of heart disease and obesity, and even reduced life span. But the new study, published in the journal Hypertension, is one of the first to find that it’s not just how much you sleep, but the the quality of your nightly slumber that can affect your risk for high blood pressure. The goal of the study, carried out by researchers at Harvard Medical School and elsewhere, was to look specifically at the slow-wave stages of sleep, which make up about 90 minutes to two hours of a normal night’s rest and represent the deepest hours of sleep. To study the effect of deep sleep on health, the scientists followed 784 healthy men who were part of an ongoing sleep study and did not have signs of high blood pressure at the start of the research. During the three-and-a-half year study, the men had their blood pressure checked at various times, and their levels of slow-wave sleep were monitored at home by a machine. After controlling for a number of variables, the researchers found that the men who spent the least time in slow-wave or deep sleep were the most likely to develop high blood pressure. Although a night of normal sleep should consist of about 25 percent slow-wave sleep, the men in the study who were at highest risk for hypertension managed to enjoy deep sleep for no more than 4 percent of their total sleep each night. © 2011 The New York Times Company

Keyword: Sleep
Link ID: 15750 - Posted: 09.01.2011

by Sarah C. P. Williams Dracula may have had it right: Young blood can restore an aging body. Scientists have discovered that blood from a 3-month-old mouse can coax the brain of an older mouse into making new brain cells. The team has not yet identified the rejuvenating factor, but they have found a blood-borne compound that seems to promote brain aging. As the body ages, the brain gradually becomes more sluggish. Even in people lucky enough to dodge neurodegenerative disorders such as Alzheimer's disease, fewer new neurons are created from stem cells in the brain, and the activity of existing neurons weakens. Neuroscientist Tony Wyss-Coray of Stanford University School of Medicine in Palo Alto, California, suspected that the changes could be mediated by factors in the blood. Previous research has shown that giving young blood to older mice boosts their immune system and muscle function. Wyss-Coray wondered whether the same might be true in the brain. Although the so-called blood-brain barrier blocks many large molecules from entering the brain from the bloodstream, the barrier isn't sealed tight everywhere, which might allow some compounds to get through. It's leakiest at places where there are brain stem cells, suggesting that these neuron precursors may have interaction with the circulatory system. Wyss-Coray's team measured neurogenesis, the creation of new neurons from stem cells, in mice that were 3 months old and mice that were almost 2 years old and considered adults. Then they surgically connected the circulatory systems of pairs of young and old mice. The number of new cells in one region of the brain's hippocampus, related to memory formation, went from fewer than 400 to almost 1000 in the older mice. In the younger mice, it dropped by almost a quarter. © 2010 American Association for the Advancement of Science

Keyword: Alzheimers; Neurogenesis
Link ID: 15749 - Posted: 09.01.2011

by Adrian Carter Most people would welcome more effective treatments for drug addiction: anyone close to someone with an addiction knows it can destroy families and lives. Recently, neuroscience has given us important insights into how changes in the brain produced by chronic drug use can lead to addiction, focussing the mind on drug use and making it difficult to stop using. This research has led some to argue that addiction is best thought of as "a chronic brain disease". Nora Volkow, the current director of the U.S. National Institute for Drug Addiction, believes that this research will foster greater acceptance of addiction as a disease requiring treatment, lessen the stigma associated with addiction, and ultimately lead to a cure. These are noble goals. However, neuroscientists also need to consider some less welcome consequences of adopting the brain disease view of addiction. Neuroscience has been used to justify highly invasive and dangerous interventions in the brain, such as psychosurgery. In China and Russia, neurosurgeons have tried to block drug use by destroying parts of the brains of addicted individuals (eg. the nucleus accumbens and the cingulated gyrus) that are implicated in motivation and the processing of reward. Unfortunately, the treatment was only minimally effective despite causing permanent brain damage. ©2006-10 Luna Media Pty Ltd.

Keyword: Drug Abuse
Link ID: 15748 - Posted: 09.01.2011

By Victoria Gill Science reporter, BBC Nature Female yellow-bellied marmots that have many male litter-mates become "tom boys", according to a study of these big, playful rodents. Developing males produce testosterone, which circulates in the mother's uterus; this male sex hormone "masculinises" the females. The phenomenon has been seen in many species, but this study shows its long-term impact on animal behaviour. The findings are published in the Royal Society journal Biology Letters. Lead researcher Raquel Monclus explained that the results emerged from a 50-year study of the marmots in the Rocky Mountain Biological Laboratory, Colorado. "We have data from generations of these animals that the lab has gathered," Dr Monclus told BBC Nature. She carried out the study while at the University of California, Los Angeles, and is now based at the UAM (Universidad Autonoma de Madrid) in Spain. The physical effects of testosterone were apparent early in this ongoing study, as it was much more difficult for the researchers to correctly identify the sex of newborn females from litters that were mostly male. BBC © 2011

Keyword: Sexual Behavior; Hormones & Behavior
Link ID: 15747 - Posted: 09.01.2011

RandyeKaye, a former radio personality in Connecticut, has just written a book, “Ben Behind His Voices: One family’s journey from the chaos of schizophrenia to hope,’’ about life with her son. A. I had always wanted to share our family’s story. One of the things that was so hard for us is I felt so alone - like nobody else’s kid had a mental illness, what’s wrong with my son, what did I do wrong? I wanted to spread the message of exactly what families go through and that recovery is possible, and some of the ways to deal with things. Q. Your son wasn’t diagnosed until years after he started acting oddly and had psychotic episodes that potentially damaged his brain. Do you resent the fact that he wasn’t diagnosed sooner? A. A lot of symptoms of mental illnesses overlap. I look back now [at the] typical pattern of gradual onset schizophrenia, and my son hit every single point: from extreme brightness, to being slightly anxious as a child, to having difficulty organizing his thoughts, to mood swings, and then to isolation from his peers. But if you look at any of those symptoms, it could be plain old adolescence, it could be drug use. There’s no way to test [for] it. Q. Mental illness can also be a financial catastrophe as well as an emotional one for a family. Did you experience that? A. My son’s college fund went to cure symptoms of an illness I didn’t know was there. A lot of families [facing mental illness] say you either have no money and the system can help you, or you have money and the system will help you when you’re out of money. Medications alone can be $6,000 a month. © 2011 NY Times Co

Keyword: Schizophrenia
Link ID: 15746 - Posted: 08.30.2011

By Sandra G. Boodman, Right away the obstetrician knew that something was very wrong. Morgan McElhinney weighed just over five pounds and had a head that was abnormally long and narrow. Her muscle tone was worrisomely floppy, and her cry unusually weak. Doctors at Frederick Memorial Hospital let Lisa Simonson McElhinney hold her newborn briefly before whisking her off to the neonatal intensive care unit. “I didn’t see her much for a few days,” recalled McElhinney of the period immediately following the birth of her fourth child, in June 2002. After nearly a week in the hospital the baby was sent home, although no one could say what was wrong. Initial tests found no obvious cause, such as a metabolic disorder. “We were scared,” said McElhinney, who manages apartment buildings in Frederick. “You try to be optimistic and say, ‘Maybe she’s not that bad, maybe she’s just really early and will grow out of it.’ Even the professionals tried to be optimistic” at first, she said. More than five years would elapse before McElhinney and her husband, Brad, learned the reason for their daughter’s problems. That knowledge brought a fresh wave of grief that rocked McElhinney and drew her to a new endeavor aimed at helping other families. The first sign something was amiss, said McElhinney, now 46, came just before she went into labor, when the baby turned from the foot-first breech position to the proper head-down position. © 1996-2011 The Washington Post

Keyword: Development of the Brain; Genes & Behavior
Link ID: 15745 - Posted: 08.30.2011

PERTH, Australia — Dolphins in one western Australian population have been observed holding a large conch shell in their beaks and using it to shake a fish into their mouths — and the behavior may be spreading. Researchers from Murdoch University in Perth were not quite sure what they were seeing when they first photographed the activity, in 2007, in which dolphins would shake conch shells at the surface of the ocean. "It's a fleeting glimpse — you look at it and think, that's kind of weird," said Simon Allen, a researcher at the university's Cetacean Research Unit. "Maybe they're playing, maybe they're socializing, maybe males are presenting a gift to a female or something like that, maybe the animals are actually eating the animal inside," he added. But researchers were more intrigued when they studied the photos and found the back of a fish hanging out of the shell, realizing that the shaking drained the water out of the shells and caused the fish that was sheltering inside to fall into the dolphins' mouths. A search through records for dolphins in the eastern part of Shark Bay, a population that has been studied for nearly 30 years, found roughly half a dozen sightings of similar behavior over some two decades. Copyright 2011 Thomson Reuters.

Keyword: Intelligence; Evolution
Link ID: 15744 - Posted: 08.30.2011

By Jennifer Viegas Years of either running from or running after animals left its mark in the human brain -- even just looking at a photo of an animal jolts our brains into action. No matter how high tech and urban we may become, animals continue to affect our brains like no other person, place or thing, shows new research in the latest issue of Nature Neuroscience. Co-author Ralph Adolphs explained to Discovery News "that it is important for the brain to be able to rapidly detect animals. The reasons for this are probably several, but would likely include the need to avoid predators and catch prey." "These abilities are at once critically important to survival and yet very difficult to do," added Adolphs, a professor of psychology, neuroscience and biology at the California Institute of Technology. "Both predator and prey detection requires fast, real-time detection of shapes that are often camouflaged in a cluttered environment." Adolphs, project leader Florian Mormann, and their colleagues recorded how the brains of 41 neurosurgical patients undergoing epilepsy monitoring responded to images of people, landmarks, animals, or objects. During 111 experimental sessions, the researchers monitored the subjects' brain activity as they sat in bed while viewing about 100 images per session. The monitoring was quite precise, showing how even individual neurons reacted. athletes © 2011 Discovery Communications, LLC

Keyword: Attention; Evolution
Link ID: 15743 - Posted: 08.30.2011

By Tina Hesman Saey Friendly intestinal bacteria not only keep the gut happy, they may help keep their host happy, too, a new study in mice finds. Mice fed broth fortified with a type of friendly intestinal bacteria called Lactobacillus rhamnosus behaved less anxiously than mice fed broth without bacteria. Those behavior changes were accompanied by differences in levels of a brain-chemical sensor and stress hormones. The bacteria telegraph these brain-chemical and behavior-changing messages via the vagus nerve, which connects the brain stem to various internal organs, researchers report online August 29 in the Proceedings of the National Academy of Sciences. Some studies have suggested that changing the mix of bacteria in the intestines could influence behavior (SN: 6/18/11, p. 26). The new research goes a step further to investigate how those changes come about, says Paul Patterson, a neuroimmunologist at Caltech in Pasadena, Calif. “Most people haven’t gone that far to look at what’s happening in the brain,” he says. The research team — led by John Bienenstock of McMaster University in Hamilton, Canada, and John Cryan of the University College Cork in Ireland — looked at the mice’s brains to examine levels of the GABA receptor, a protein that senses and responds to an important brain chemical messenger called GABA. Alterations in the way GABA and other brain chemical systems work influence behavior. Mice fed bacteria-containing broth had higher levels of the receptor protein in some parts of the brain and lower levels in other parts than did mice fed sterile broth. © Society for Science & the Public 2000 - 2011

Keyword: Stress
Link ID: 15742 - Posted: 08.30.2011