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by Meredith Wadman Fresh from attending President Barack Obama’s announcement of the BRAIN Initiative at the White House on April 2nd, Society for Neuroscience president Larry Swanson, a neurobiologist at the University of Southern California, composed this letter to SFN’s nearly 42,000 members. In the 5 April missive, Swanson, writing on behalf of SFN’s executive committee, calls the Brain Research through Advancing Innovative Neurotechnologies (BRAIN) Initiative “tremendously positive” for neuroscience. Its aim is to let scientists examine and record the activity of millions of neurons at they function at the speed of thought; ultimately, applications to several human diseases are hoped for. The project comes at a critical time in neuroscience, Swanson writes: a time of huge new opportunities coupled with stagnant or slumping government budgets for basic science research. (In the budget he released last week, Obama asked Congress to provide about $100 million to launch the BRAIN Initiative in 2014.) But the SFN letter makes it clear that Swanson wants a lid put on public criticism of the nascent project, which is expected to last more than a decade and ultimately cost several billion dollars. “It is important that our community be perceived as positive about the incredible opportunity represented in the President’s announcement,” Swanson wrote. “If we are perceived as unreasonably negative or critical about initial details, we risk smothering the initiative before it gets started.” In case anyone missed the point, he adds that he encourages “healthy debate” and “rigorous dialogue” but urges SFN members to “bring all this to the table through our scientific communications channels and venues.” He also notes that the National Institutes of Health has enlisted a team of “distinguished” neuroscientists to conduct a “rigorous” planning process. © 2013 Nature Publishing Group

Keyword: Brain imaging
Link ID: 18039 - Posted: 04.16.2013

By Jill U. Adams, Urban living may be harmful to your ears. That’s the takeaway from a study that found that more than eight in 10 New Yorkers were exposed to enough noise to damage their hearing. Perhaps more surprising was that so much of the city dwellers’ noise exposure was related not to noisy occupations but rather to voluntary activities such as listening to music. Which makes it hard for me not to worry that when my 16-year-old son is sitting nearby with his earbuds in, I can hear his music. There’s a pretty good chance that he’s got the volume up too loud — loud enough to potentially damage the sensory cells deep in his ear and eventually lead to permanent hearing loss. That’s according to Christopher Chang, an ear, nose and throat doctor at Fauquier ENT Consultants in Warrenton, who sees patients every day with hearing-related issues. “What he’s hearing is way too loud, because it’s concentrated directly into the ear itself,” he says of my son, adding that the anatomy of the ear magnifies sound as it travels through the ear canal. Listening to music through earbuds or headphones is just one way that many of us are routinely exposed to excessive noise. Mowing the lawn, going to a nightclub, riding the Metro, using a power drill, working in a factory, playing in a band and riding a motorcycle are activities that can lead to hearing problems. Aging is the primary cause of hearing loss; noise is second, says Brian Fligor, who directs the diagnostic audiology program at Boston Children’s Hospital, and it’s usually the culprit when the condition affects younger people. Approximately 15 percent of American adults between the ages of 20 and 69 have high-frequency hearing loss, probably the result of noise exposure, according to the National Institute on Deafness and Other Communication Disorders. © 1996-2013 The Washington Post

Keyword: Hearing
Link ID: 18038 - Posted: 04.15.2013

By ERIC R. KANDEL THIS month, President Obama unveiled a breathtakingly ambitious initiative to map the human brain, the ultimate goal of which is to understand the workings of the human mind in biological terms. Many of the insights that have brought us to this point arose from the merger over the past 50 years of cognitive psychology, the science of mind, and neuroscience, the science of the brain. The discipline that has emerged now seeks to understand the human mind as a set of functions carried out by the brain. This new approach to the science of mind not only promises to offer a deeper understanding of what makes us who we are, but also opens dialogues with other areas of study — conversations that may help make science part of our common cultural experience. Consider what we can learn about the mind by examining how we view figurative art. In a recently published book, I tried to explore this question by focusing on portraiture, because we are now beginning to understand how our brains respond to the facial expressions and bodily postures of others. The portraiture that flourished in Vienna at the turn of the 20th century is a good place to start. Not only does this modernist school hold a prominent place in the history of art, it consists of just three major artists — Gustav Klimt, Oskar Kokoschka and Egon Schiele — which makes it easier to study in depth. As a group, these artists sought to depict the unconscious, instinctual strivings of the people in their portraits, but each painter developed a distinctive way of using facial expressions and hand and body gestures to communicate those mental processes. © 2013 The New York Times Company

Keyword: Vision; Attention
Link ID: 18037 - Posted: 04.15.2013

By Gary Stix People who lose a limb often experience the sensation of still having the missing arm or leg. Phantom limbs, in fact, have spurred a whole line of independent research among neuroscientists. But it appears that all of us may be capable of these sensations, even if arms and legs remain intact. If we can conjure a phantom limb just like that, it raises all kinds of enticing questions for philosophers as well as scientists about what exactly constitutes our perception of the physical self. Karolinska Institute researchers report online in the Journal of Cognitive Neuroscience that they can induce a sensation of a phantom hand in just a short time. Watch this simple experiment here: © 2013 Scientific American

Keyword: Pain & Touch
Link ID: 18036 - Posted: 04.15.2013

Nearly half of those with Parkinson's face regular discrimination, such as having their symptoms mistaken for drunkenness, a survey suggests. The survey of more than 2,000 people was commissioned by charity Parkinson's UK. One person in 500 people is affected by the condition in Britain. Parkinson's sufferer Mark Worsfold was arrested during last year's Olympics because police thought he looked suspicious. He was detained during the cycling road race in Leatherhead, Surrey, reportedly because he was not smiling - the condition means his face can appear expressionless. Parkinson's is a progressive neurological condition that attacks the part of the brain that controls movement. The main symptoms of Parkinson's are tremors or shaking that cannot be controlled, and rigidity of the muscles, which can make movement difficult and painful. Speech, language and facial expressions can also be affected. Most people who get it are aged 50 or over but younger people can have it too. The survey found that one in five people living with Parkinson's had been mistaken for being drunk, while one in 10 had been verbally abused or experienced hostility in public because of their condition. Around 62% said they thought the public had a poor understanding of how the condition affects people. BBC © 2013

Keyword: Parkinsons
Link ID: 18035 - Posted: 04.15.2013

By IAN LOVETT WEST HOLLYWOOD, Calif. — A potentially deadly strain of meningitis, which has left one resident brain dead, has sent a shiver through the large gay community here, as public health officials have urged residents to be on the lookout for any symptoms of the disease. Although only one case has been confirmed in the area, officials said, the onset follows an outbreak of deadly meningitis among gay men in New York City. At least 22 men have contracted meningitis in New York since 2010, 13 of them this year, and 7 have died. Health officials have not yet determined if there is any connection between the cases in New York and the one here. But the similarities have ignited fears that this case could be an early sign of a bicoastal outbreak. “The lesson we learned 30 years ago in the early days of H.I.V. and AIDS is that people were not alerted to what was going on and a lot of infections occurred that didn’t need to occur,” said John Duran, a West Hollywood city councilman and one of the few openly H.I.V.-positive elected officials in the country. “So even with an isolated case here, we need to sound the alarms, especially given the cases in New York.” In New York, the city health department issued a warning last month, urging all men who regularly have intimate contact with other men to be vaccinated for meningitis. Officials here have thus far been reluctant to do the same. At a news conference on Friday, Dr. Maxine E. Liggins, with the Los Angeles County Department of Public Health, warned residents to watch for early signs of meningococcal meningitis, including a severe headache and stiff neck. The disease, a bacterial infection of the membrane surrounding the brain and the spinal cord, can be effectively treated with antibiotics if detected early, although it can intensify quickly. © 2013 The New York Times Company

Keyword: Miscellaneous
Link ID: 18034 - Posted: 04.15.2013

Geeta Dayal Earlier this month, Barack Obama unveiled a grand, new U.S. government initiative called BRAIN (Brain Research through Advancing Innovative Neurotechnologies) that he said would provide “a dynamic picture of the brain in action” and help humanity “better understand how we think and how we learn and how we remember.” The brain-mapping effort is set to cost $100-million in 2014, and hundreds of millions more in the years to come. This follows last year’s move in Ottawa to create a Canada Brain Research Fund with up to $100-million in matching funds to the Brain Canada Foundation. For Mr. Obama, it may be a way to put a triumphant stamp on the presidential legacy, but to those familiar with the field, the new program is a question mark. “This sounds like, um, a PR splash,” David Hovda, director of the UCLA Brain Injury Research Center, told National Public Radio. Donald Stein, an Emory University neuroscientist, argued on LiveScience.com that “without specific goals, hypotheses or endpoints, the research effort becomes a fishing expedition.” Mr. Obama compared BRAIN to the Human Genome Project for its potential return on investment. The comparison is also apt on another level: Like genetics in the past decade, neuroscience seems to have reached a peak in the public consciousness. And that’s big business not just for science, but for the media and publishing industries. Peruse bestseller lists during the past few years and you’ll find a host of titles in neuroscience and cognitive or social psychology, from Thinking, Fast and Slow and The Brain That Changes Itself to Proof of Heaven: A Neurosurgeon’s Journey Into the Afterlife and How to Create a Mind: The Secret of Human Thought Revealed. The well of material is virtually endless – after all, every aspect of the human experience can be tied, somehow, to the brain. As a result, the hype can be bottomless too. Lately a wave of “neuroskeptics” have been calling for more sober second thought. © Copyright 2013 The Globe and Mail Inc

Keyword: Brain imaging
Link ID: 18033 - Posted: 04.13.2013

Kristoffer Famm, et al. Imagine a day when electrical impulses are a mainstay of medical treatment. Your clinician will administer 'electroceuticals' that target individual nerve fibres or specific brain circuits to treat an array of conditions. These treatments will modulate the neural impulses controlling the body, repair lost function and restore health. They could, for example, coax insulin from cells to treat diabetes, regulate food intake to treat obesity and correct balances in smooth-muscle tone to treat hypertension and pulmonary diseases. All this is within reach if researchers from disparate disciplines in academia and industry work together. Here, we outline what needs to be done to bring about electroceuticals and unveil a public–private research initiative and an award that we hope will catalyse the field. Electrical impulses — action potentials — are the language of the body's nervous system. Virtually all organs and functions are regulated through circuits of neurons communicating through such impulses1. Two features make these circuits excellent targets for therapeutic intervention. First, they comprise discrete components — interconnected cells, fibre tracts and nerve bundles — allowing for pinpoint intervention. Second, they are controlled by patterns of action potentials, which can be altered for treatment. Already, devices that harness electrical impulses are used to treat disease. Pacemakers and defibrillators save millions of lives each year; deep-brain stimulation dramatically improves the quality of life for people with Parkinson's disease and depression; sacral-nerve stimulation restores some bladder control in people with paraplegia, and vagus-nerve stimulation shows clinical benefits in diseases ranging from epilepsy to rheumatoid arthritis2. But these devices do not target specific cells within circuits. © 2013 Nature Publishing Group

Keyword: Depression; Schizophrenia
Link ID: 18032 - Posted: 04.13.2013

By Steven E. Hyman During the past three years the global pharmaceutical industry has significantly decreased its investment in new treatments for depression, bipolar disorder, schizophrenia, and other psychiatric disorders.1 Some large companies, such as GlaxoSmithKline, have closed their psychiatric laboratories entirely. Others, such as Pfizer, have markedly decreased the size of their research programs. Yet others, such as AstraZeneca, have brought their internal research to a close and are experimenting with external collaborations on a smaller scale. This retreat has occurred despite the fact that mental disorders are not only common worldwide, but also increasingly recognized by healthcare systems. There is, moreover, vast unmet medical need, meaning that many individuals with mental disorders remain symptomatic and often disabled despite existing treatments. For example, people suffering with the depressed phase of bipolar disorder often continue to experience severe symptoms even when they take multiple medications with serious side effects. For some significantly disabling conditions, such as the core social deficits of autism and the cognitive impairments of schizophrenia, there simply are no effective treatments. Because mental disorders are highly prevalent and our ability to treat them remains limited, these illnesses cause enormous societal burden. In aggregate, they are the world’s leading cause of disability.2 In addition, this retreat has happened despite the fact that different classes of psychiatric drugs have been among the industry’s most profitable products during the last several decades—and despite the fact that, according to Medco Health Solutions, one in five American adults now takes at least one psychiatric drug. Among the earliest commercial successes were the Valium-like benzodiazepines, used both as tranquilizers and as sleeping pills. These were followed by the Prozac-like selective serotonin reuptake inhibitor (SSRI) antidepressants. Most recently, “second-generation” antipsychotic drugs have been among the global revenue leaders for the pharmaceutical industry, serious side effects notwithstanding. That’s why it’s surprising that almost all industry research dollars are invested in cancer, metabolism, autoimmunity, and other disease areas. Copyright 2013 The Dana Foundation

Keyword: Depression; Schizophrenia
Link ID: 18031 - Posted: 04.13.2013

By Meghan Rosen Whether you’re rocking out to Britney Spears or soaking up Beethoven’s classics, you may be enjoying music because it stimulates a guessing game in your brain. This mental puzzling explains why humans like music, a new study suggests. By looking at activity in just one part of the brain, researchers could predict roughly how much volunteers dug a new song. When people hear a new tune they like, a clump of neurons deep within their brains bursts into excited activity, researchers report April 12 in Science. The blueberry-sized cluster of cells, called the nucleus accumbens, helps make predictions and sits smack-dab in the “reward center” of the brain — the part that floods with feel-good chemicals when people eat chocolate or have sex. The berry-sized bit acts with three other regions in the brain to judge new jams, MRI scans showed. One region looks for patterns, another compares new songs to sounds heard before, and the third checks for emotional ties. As our ears pick up the first strains of a new song, our brains hustle to make sense of the music and figure out what’s coming next, explains coauthor Valorie Salimpoor, who is now at the Baycrest Rotman Research Institute in Toronto. And when the brain’s predictions are right (or pleasantly surprising), people get a little jolt of pleasure. All four brain regions work overtime when people listen to new songs they like, report the researchers, including Robert Zatorre of the Montreal Neurological Institute at McGill University © Society for Science & the Public 2000 - 2013

Keyword: Hearing; Drug Abuse
Link ID: 18030 - Posted: 04.13.2013

by Patrick Russell Many people who have had a limb amputated report feeling sensations that appear to come from their missing arm or leg. Now researchers have found that anyone can experience having such a phantom limb. "Previous research shows that you can convince a person that a rubber hand is their own by putting it on a table in front of them and stroking it in synchrony with their real hand," explains Arvid Guterstam at the Karolinska Institute in Stockholm, Sweden, who led the study. The illusion does not work with a block of wood, he says. "But our study shows that if you take away this rubber hand, people will attribute sensations to an invisible entity." Guterstam and his colleagues made volunteers sit at a table with their right arm hidden from view behind a screenMovie Camera. An experimenter then applied brush strokes to the concealed hand and, simultaneously, to a portion of empty space in full view of each volunteer. "We discovered that most participants, within less than a minute, transfer the sensation of touch to the region of empty space where they see the paintbrush move, and experience an invisible hand in that position," says Guterstam. Mock stabbing Experimenters also mimicked stabbing the phantom hand with a kitchen knife, while monitoring volunteers' stress level. To minimise any effect related to seeing the knife for the first time, the volunteers were warned that it would be used at some point. The researchers found that during the mock stabbing, stress levels, measured using a type of sweat test, went up in about 75 per cent of the 234 participants. © Copyright Reed Business Information Ltd.

Keyword: Pain & Touch; Attention
Link ID: 18029 - Posted: 04.13.2013

By Bill Andrews In a paper sure to please lazy stand-up comics and beleaguered husbands everywhere, scientists say that men do indeed have a hard time understanding women. Recent results show that men have a significantly harder time recognizing women’s emotions than they do men’s, and that men seem to use different parts of their brain when ascribing intentions and feelings to women versus men. Previous experiments had suggested that men are naturally wired to be more intuitive toward other men’s mental states and emotions. Eager to figure out why and how this could be, the researchers studied the brains of 22 male participants as they received a version of a well-known empathy test called the “Reading the Mind in the Eyes Test.” (You can take a version of the test online here.) As the name suggests, the test consists of snapshots of pairs of eyes. Pairs of eyes were shown in succession to each participant, who had to determine either the gender or the emotional state of the person pictured. This all took place within an MRI machine, allowing the researchers to see which parts of the brain were active while participants made their determinations. Participants were about equally good at guessing the gender of male and female eyes, but the men did significantly worse at recognizing the emotions of the female eyes. They correctly interpreted about 87 percent of men’s eyes but only about 76 percent of women’s eyes. Participants also took longer to judge women’s emotions—about 40 milliseconds longer on average. Thus, in effect, men can “read” other men’s eyes faster and better, the researchers report in PLOS ONE.

Keyword: Emotions; Sexual Behavior
Link ID: 18028 - Posted: 04.13.2013

Sid Perkins The two-million-year-old remains of a novel hominin discovered in August 2008 are an odd blend of features seen both in early humans and in the australopithecines presumed to have preceded them. A battery of six studies1–6 published today in Science scrutinizes the fossils of Australopithecus sediba from head to heel and yields unprecedented insight into how the creature walked, chewed and moved. Together, the studies suggest that this hominin was close to the family tree of early humans — although it remains controversial whether it was one of our direct ancestors. “We see evolution in action across this skeleton,” says Lee Berger, a palaeoanthropologist at the University of the Witwatersrand in Johannesburg, South Africa. For instance, whereas the creature’s arms are ape-like, its hands and wrists are remarkably like those of humans. And although the hominin’s pelvis is shaped like a modern human's, its torso included a narrow upper rib cage like those found in apes. One of the six studies focused on Au. sediba’s teeth1, comparing 22 different aspects across hundreds of teeth from several other species of australopithecines and thousands of early human teeth. Tooth similarities among the species are more likely to signify common ancestry than independent evolution towards a beneficial design, says Debbie Guatelli-Steinberg, an anthropologist at Ohio State University in Columbus. That's because most of the characteristics the team chose to study, such as the subtle curvature of a portion of the tooth’s surface, are not likely to be evolutionarily useful. © 2013 Nature Publishing Group

Keyword: Evolution
Link ID: 18027 - Posted: 04.13.2013

by Simon Makin The first drug specifically designed to improve cognitive impairment in Down's syndrome is being tested in humans. David Nutt, former drug policy adviser to the UK government, told delegates at the Festival of Neuroscience in London yesterday that he is collaborating with pharmaceutical company Roche in trials of a substance it developed, called RG1662. RG1662 reverses the effects of a chemical messenger in the brain called GABA – a neurotransmitter that inhibits brain activity. The drug acts on a specific type of brain receptor found mostly in the hippocampus, a part of the brain involved in memory. It is thought that it will reduce excessive inhibition in the hippocampus, thought to underlie memory and learning problems commonly seen in people with Down's. The study is currently assessing safety and tolerability of the drug in 33 adults with Down's, but researchers will also measure motor skills, reaction time and memory, and compare the results with those of people taking a placebo. The aim is to find appropriate doses to use in a full clinical trial, which Nutt says should happen this year. Roche said in a statement that RG1662 may help people with Down's as it has "a unique pharmacology that enables the targeting of GABA over-activity mainly in brain systems important for cognition, learning and memory". © Copyright Reed Business Information Ltd

Keyword: Learning & Memory
Link ID: 18026 - Posted: 04.13.2013

Published by scicurious I love salt. It's just delicious. I wrote this post while noshing on deliciously salty popcorn, after a dinner which I put salt on. I crave salt so much that my parents used to joke about getting me a salt lick. And I'm not alone. Sodium is an incredibly important part of life, which means it's also an important part of what we eat. To make sure we get enough salt, animals have evolved salt-sensing systems, and low levels (below 100 mM of NaCl) of salt are very attractive. But there IS such a thing as too much salt. High levels of salt (>300 mM NaCl) are really aversive (from personal experience, I wonder if Carrabba's restaurant has concentrations of salt in their food over 300 mM). Most animals will quickly turn up their noses at a high salt concentration. You probably know that you have classes of receptors on your tongue for taste (though they are not clustered into areas of your mouth, like front for sweetness, as previously thought). You have sweet, umami (savory), bitter, sour, and salt. In most animals, sweet and umami are always attractive, while bitter and sour are nasty (except where we have overcome the aversion to enjoy things like coffee and beer). Salt, though, is the only one that goes two ways, with low levels being attractive and high levels being aversive. Now we know how low salt works. The salt receptors that are currently known are good for detecting low salt. But high salt, that's more difficult. First of all, our aversion to high salt concentrations is not very selective. While low salt detection is limited to good old NaCl, high salt detection is non-specific, working for many salts including NaCl, but others as well (like KCl). Neurotic Physiology Copyright © 2013

Keyword: Chemical Senses (Smell & Taste)
Link ID: 18025 - Posted: 04.13.2013

by Helen Shen A thermometer is great for measuring a fever, but when it comes to pain, doctors must rely on the age-old question, "How bad is it?" Scientists have long struggled to find physiological signs that can reliably tell "ouch" from "@#%!" and everything in between. Now, a brain scanning study suggests that painful heat excites a specific pattern of neural activity that could hold the key to better diagnosis and treatment of all kinds of pain in the future. Functional magnetic resonance imaging (fMRI) studies have shown that certain areas of the brain—including the anterior cingulate cortex, somatosensory cortex, and thalamus—activate when people experience pain. But those same regions also light up in response to other experiences, such as painful thoughts or social rejection. In recent years, scientists have looked for a particular pattern of activity across these areas that single out the experience of physical pain. "What we're evolving towards is trying to predict quantitatively from patterns of brain activity how much an individual is feeling," says Tor Wager, a neuroscientist at the University of Colorado, Boulder. In the new study, Wager's group performed fMRI brain scans on a total of 114 healthy participants while delivering different amounts of heat to the volunteers' arms with a computer-controlled hot plate. In an initial experiment, the scientists used data from 20 people to find a brain-wide pattern of excitation and inhibition—a neural "signature"—that changed reliably as people experienced varying degrees of heat, ranging from painless to scalding. In the remainder of the study, Wager and his colleagues were able use the signature derived from the first group to predict pain responses in a completely different set of subjects—a promising sign for one day using such a model on patients suffering from unknown conditions, he says. © 2010 American Association for the Advancement of Science.

Keyword: Pain & Touch; Brain imaging
Link ID: 18024 - Posted: 04.11.2013

by Elizabeth Norton A loving gaze helps firm up the bond between parent and child, building social skills that last a lifetime. But what happens when mom is blind? A new study shows that the children of sightless mothers develop healthy communication skills and can even outstrip the children of parents with normal vision. Eye contact is one of the most important aspects of communication, according to Atsushi Senju, a developmental cognitive neuroscientist at Birkbeck, University of London. Autistic people don't naturally make eye contact, however, and they can become anxious when urged to do so. Children for whom face-to-face contact is drastically reduced—babies severely neglected in orphanages or children who are born blind—are more likely to have traits of autism, such as the inability to form attachments, hyperactivity, and cognitive impairment. To determine whether eye contact is essential for developing normal communication skills, Senju and colleagues chose a less extreme example: babies whose primary caregivers (their mothers) were blind. These children had other forms of loving interaction, such as touching and talking. But the mothers were unable to follow the babies' gaze or teach the babies to follow theirs, which normally helps children learn the importance of the eyes in communication. Apparently, the children don't need the help. Senju and colleagues studied five babies born to blind mothers, checking the children's proficiency at 6 to 10 months, 12 to 15 months, and 24 to 47 months on several measures of age-appropriate communications skills. At the first two visits, babies watched videos in which a woman shifted her gaze or moved different parts of her face while corresponding changes in the baby's face were recorded. Babies also followed the gaze of a woman sitting at a table and looking at various objects. © 2010 American Association for the Advancement of Science

Keyword: Development of the Brain; Emotions
Link ID: 18023 - Posted: 04.11.2013

By Daisy Yuhas Less than two hundred years ago, schizophrenia emerged from a tangle of mental disorders known simply as madness. Yet its diagnosis remains shrouded in ambiguity. Only now is the Diagnostics and Statistical Manual of Mental Disorders, psychiatrists’ primary guidebook, shedding the outdated, nineteenth-century descriptions that have characterized schizophrenia to this day. "There is substantial dissatisfaction with schizophrenia treated as a disease entity, it's symptoms are like a fever—something is wrong but we don't know what," says William Carpenter, a psychiatrist at the University of Maryland and chair of the manual’s Psychotic Disorder Workgroup. Psychiatrists may discover that this disorder is not a single syndrome after all but a bundle of overlapping conditions. © 2013 Scientific American,

Keyword: Schizophrenia
Link ID: 18022 - Posted: 04.11.2013

by Caroline Williams When it comes to making decisions, it seems that the conscious mind is the last to know. We already had evidence that it is possible to detect brain activity associated with movement before someone is aware of making a decision to move. Work presented this week at the British Neuroscience Association (BNA) conference in London not only extends it to abstract decisions, but suggests that it might even be possible to pre-emptively reverse a decision before a person realises they've made it. In 2011, Gabriel Kreiman of Harvard University measured the activity of individual neurons in 12 people with epilepsy, using electrodes already implanted into their brain to help identify the source of their seizures. The volunteers took part in the "Libet" experiment, in which they press a button whenever they like and remember the position of a second hand on a clock at the moment of decision. Kreiman discovered that electrical activity in the supplementary motor area, involved in initiating movement, and in the anterior cingulate cortex, which controls attention and motivation, appeared up to 5 seconds before a volunteer was aware of deciding to press the button (Neuron, doi.org/btkcpz). This backed up earlier fMRI studies by John-Dylan Haynes of the Bernstein Center for Computational Neuroscience in Berlin, Germany, that had traced the origins of decisions to the prefrontal cortex a whopping 10 seconds before awareness (Nature Neuroscience, doi.org/cs3rzv). "It's always nice when two lines of research converge and to know that what we see with fMRI is actually there in the neurons," says Haynes. © Copyright Reed Business Information Ltd.

Keyword: Consciousness
Link ID: 18021 - Posted: 04.11.2013

by Ed Yong The brain has hit the big time. Barack Obama has just announced $100 million of funding for the BRAIN Intitiative—an ambitious attempt to apparently map the activity of every neuron in the brain. On the other side of the Atlantic, the Human Brain Project will try to simulate those neurons with a billion euros of funding from the European Commission. And news about neuroscience, from dream-decoding to mind-melding to memory-building, regularly dominates the headlines. But while the field’s star seems to be rising, a new study casts a disquieting shadow upon the reliability of its results. A team of scientists led by Marcus Munafo from the University of Bristol analysed a broad range of neuroscience studies and found them plagued by low statistical power. Statistical power refers to the odds that a study will find an effect—say, whether antipsychotic drugs affect schizophrenia symptoms, or whether impulsivity is linked to addiction—assuming those effects exist. Most scientists regard a power of 80 percent as adequate—that gives you a 4 in 5 chance of finding an effect if there’s one to be found. But the studies that Munafo’s team examined tended to be so small that they had an average (median) power of just 21 percent. At that level, if you ran the same experiment five times, you’d only find an effect on one of those. The other four tries would be wasted. But if studies are generally underpowered, there are more worrying connotations beyond missed opportunities. It means that when scientists do claim to have found effects—that is, if experiments seem to “work”—the results are less likely to be real. And it means that if the results are actually real, they’re probably bigger than they should be. As the team writes, this so-called “winner’s curse” means that “a ‘lucky’ scientist who makes the discovery in a small study is cursed by finding an inflated effect.”

Keyword: Brain imaging; Schizophrenia
Link ID: 18020 - Posted: 04.11.2013