Chapter 2. Cells and Structures: The Anatomy of the Nervous System
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By Neuroskeptic Newly discovered papers have shed light on a fascinating episode in the history of neuroscience: Weighing brain activity with the balance The story of the early Italian neuroscientist Dr Angelo Mosso and his ‘human circulation balance’ is an old one – I remember reading about it as a student, in the introductory bit of a textbook on fMRI – but until now, the exact details were murky. In the new paper, Italian neuroscientists Sandrone and colleagues report that they’ve unearthed Mosso’s original manuscripts from an archive in Milan. Mosso worked in the late 19th century, an era that was – in retrospect – right at the dawn of modern neuroscience. A major question at that time was the relationship between brain function and blood flow. His early work included studies of the blood pressure in the brains of individuals with skull defects. His most ambitious project, however, was his balance – or as he sometimes called it, according to his daughter, his ‘metal cradle’ or ‘machine to weigh the soul’. It was in essence just a large balance. A volunteer lay on a table, their head on one side of the scale’s pivot and their feet on the other. It was carefully adjusted so that the two sides were perfectly balanced. The theory was that if mental activity caused increased brain blood flow, it ought to increase the weight of the head relative to the rest of the body, so that side of the balance would fall.
Keyword: Brain imaging
Link ID: 18188 - Posted: 05.23.2013
By John McCarthy Into brains of newborn mice, researchers implanted human “progenitor cells.” These mature into a type of brain cell called astrocytes (see below). They grew into human astrocytes, crowding out mouse astrocytes. The mouse brains became chimeras of human and mouse, with the workhorse mouse brain cells – neurons – nurtured by billions of human astrocytes. Neuroscience is only beginning to discover what astrocytes do in brains. One job that is known is that they help neurons build connections (synapses) with other neurons. (Firing neurotransmitter molecules across synapses is how neurons communicate.) Human astrocytes are larger and more complex than those of other mammals. Humans’ unique brain capabilities may depend on this complexity. Human astrocytes certainly inspired the mice. Their neurons did indeed build stronger synapses. (Perhaps this was because human astrocytes signal three times faster than mouse astrocytes do.) Mouse learning sharpened, too. On the first try, for instance, altered mice perceived the connection between a noise and an electric shock (a standard learning test in mouse research). Normal mice need a few repetitions to get the idea. Memories of the doctored mice were better too: they remembered mazes, object locations, and the shock lessons longer. The reciprocal pulsing of billions of human and mouse brain cells inside a mouse skull is a little creepy. Imagine one of these hybrid mice exploring your living room. Would you feel like a Stone Age tribesman observing a toy robot? Does the thing think? © 2013 Scientific American
Posted by Helen Shen More than 150 neuroscientists descended on Arlington, Virginia this week to begin planning the Brain Research through Advancing Innovative Neurotechnologies (BRAIN) Initiative—an ambitious but still hazy proposal to understand how the brain works by recording activity from an unprecedented numbers of neurons at once. President Barack Obama announced the initiative on 2 April, which will be carried out by three federal agencies—the National Institutes of Health (NIH), the National Science Foundation (NSF), and the Defense Advanced Research Projects Agency (DARPA)—alongside a handful of private foundations. Most neuroscientists have relished the attention on their field, but have also been left wondering what it means in scientific terms to “understand” the brain, what it will take to get there, and how much will be feasible in the programme’s projected 10-year lifespan. They gathered at an inaugural NSF planning meeting taking place from 5-6 May to discuss their ideas and concerns. “The belief is we’re ready for a leap forward,” says Van Wedeen, a neurobiologist at Harvard Medical School in Boston, Massachusetts, and one of the NSF meeting organizers. “Which leap and in which direction is still being debated.” The NSF group invited researchers representing neuroscience, computer science, and engineering — as many as would fit in the hotel conference room. Another estimated 200 or so followed the meeting by live webcast on Monday. Roughly 75 participants accepted NSF’s open invitation to submit one-page documents outlining the major © 2013 Nature Publishing Group,
Keyword: Brain imaging
Link ID: 18126 - Posted: 05.07.2013
Distinct patterns of brain activity are linked to greater rates of relapse among alcohol dependent patients in early recovery, a study has found. The research, supported by the National Institutes of Health, may give clues about which people in recovery from alcoholism are most likely to return to drinking. "Reducing the high rate of relapse among people treated for alcohol dependence is a fundamental research issue," said Kenneth R. Warren, Ph.D., acting director of the National Institute on Alcohol Abuse and Alcoholism (NIAAA), part of NIH. "Improving our understanding of the neural mechanisms that underlie relapse will help us identify susceptible individuals and could inform the development of other prevention strategies." Using brain scans, researchers found that people in recovery from alcoholism who showed hyperactivity in areas of the prefrontal cortex during a relaxing scenario were eight times as likely to relapse as those showing normal brain patterns or healthy controls. The prefrontal brain plays a role in regulating emotion, the ability to suppress urges, and decision-making. Chronic drinking may damage regions involved in self-control, affecting the ability to regulate cravings and resist relapse. Findings from the study, which was funded by NIAAA, appear online at the JAMA Psychiatry website.
by Sara Reardon An electronic patch can analyse complex brainwaves and listen in on a fetus’s heart MIND reading can be as simple as slapping a sticker on your forehead. An "electronic tattoo" containing flexible electronic circuits can now record some complex brain activity as accurately as an EEG. The tattoo could also provide a cheap way to monitor a developing fetus. The first electronic tattoo appeared in 2011, when Todd Coleman at the University of California, San Diego, and colleagues designed a transparent patch containing electronic circuits as thin as a human hairMovie Camera. Applied to skin like a temporary tattoo, these could be used to monitor electrophysiological signals associated with the heart and muscles, as well as rudimentary brain activity. To improve its usefulness, Coleman's group has now optimised the placement of the electrodes to pick up more complex brainwaves. They have demonstrated this by monitoring so-called P300 signals in the forebrain. These appear when you pay attention to a stimulus. The team showed volunteers a series of images and asked them to keep track of how many times a certain object appeared. Whenever volunteers noticed the object, the tattoo registered a blip in the P300 signal. The tattoo was as good as conventional EEG at telling whether a person was looking at the target image or another stimulus, the team told a recent Cognitive Neuroscience Society meeting in San Francisco. © Copyright Reed Business Information Ltd.
by Scicurious Mmmmm beer! Just a sip is enough to prime the brain's dopamine addiction circuits, if reports of a new study are to be believed. Photograph: Johnny Green/PA It's been a long day at work, followed by a long workout. I'm tired, and all I really want is to relax with a beer. I grab one out of the fridge and take a sip. I feel better already. A new study tells us that this is due to dopamine, a neurotransmitter that plays an important role in things like motivation and reward. Drugs of abuse, such as cocaine, increase dopamine levels in areas of the brain associated with the expectation of reward, such as the ventral striatum, and this increase is part of what makes them feel so good, and do so bad. But dopamine can also signal the expectation of something that might be rewarding. This means that as we learn that some things are rewarding, like, say, beer, we begin to respond, not only to the alcohol, but to the cues that alcohol is coming: to the beer bottles, the glass, or the taste. And taste is what this study looked at. The authors took 49 male beer drinkers and divided them up into three groups: those with a family history of alcoholism, those without, and those who didn't know. They used positron emission tomography (PET) to examine how the dopamine in their brains responded to a taste of beer. The big effect? The mere taste of your favourite beer (15 millilitres – not enough to get any effects of the alcohol) produces an increase in dopamine in the ventral striatum, as well as an increased desire to … drink more beer. This suggests that a cue (the taste) produces a sign of reward expectation long before the alcohol hits your system. And the effect of the taste of beer on dopamine in the ventral striatum was larger in people who had a family history of alcohol abuse. What's not to love! It's beer! It's dopamine! It's brain scans! Of course the media got excited. © 2013 Guardian News and Media Limited
By Puneet Kollipara Brain research has been on a lot of minds lately in the nation’s capital. After offering a brief shout-out to Alzheimer’s research in his February State of the Union address, President Barack Obama went a step further in April by announcing a decade-long effort to develop advanced tools for tracking human brain activity. The administration dubbed it the Brain Research through Advancing Innovative Neurotechnologies initiative, and proposed spending $100 million on the program in the 2014 fiscal year. Scientists have discussed such an endeavor for years, and pushed hard for it in the past few months. Writing March 15 in Science, researchers say the project would develop technologies to probe brain activity on a far greater scale and with higher resolution than is now possible. Current tools can monitor only small numbers of individual neurons at a time or capture blurry, bird’s-eye views of brain activity. The new tools would enable real-time mapping of how the thousands or millions of neurons in coordinated groups, known as circuits, work together. Brain functions — and, in many cases, dysfunctions — are thought to emerge from this still poorly described circuit level. “There’s no way to build a map until you develop the tools,” says Rafael Yuste, a neuroscientist at Columbia University’s Kavli Institute for Brain Science and one of the project’s proponents. Researchers call for developing three sets of tools to better understand brain circuits. One focus is on the creation of tools to measure the activities of all the individual neurons in a circuit. Another is on technologies to experimentally manipulate these neurons. The third tool set would store, analyze and make the data accessible to all researchers. © Society for Science & the Public 2000 - 2013
Keyword: Brain imaging
Link ID: 18046 - Posted: 04.20.2013
By Neuroskeptic A new paper could prompt a rethink of a technique that’s become very hot in neuroscience lately: Confounds in multivariate pattern analysis The authors are Princetonians Michael T. Todd and colleagues, and the method in question is multivariate pattern analysis (MVPA). I’ve written about this before and there’s a blog dedicated to it. MVPA searches for relatively subtle patterns of brain activity, most commonly in fMRI data. For example, a conventional fMRI study might compare activity when someone’s looking at a picture, compared to a blank screen, and would find increases of activity in the visual cortex. But MVPA might take two different pictures, and see if there’s a pattern of activity that’s unique to one picture over the other – even if overall activity in the visual cortex is the same. Neuroscientists have fallen in love with MVPA (and related methods) over the past 5 years, mainly I think because it’s promised to let us ‘read’ the brain: to not just see where in the brain things happen, but to glimpse what information is being represented. In the new paper, Todd et al make a very simple point: all MVPA really shows is that there are places where, in most people’s brain, activity differs when they’re doing one thing as opposed to another. But there infinite reasons why that might be the case, many of them rather trivial. The authors give the example of two very similar tasks, A and B. We’ll say these are imagining apples and imagining bananas. You scan some people doing A and B. You run a standard fMRI analysis, and find that nowhere in the brain shows a difference in activity, on average, between the two (as expected – they are similar.)
Keyword: Brain imaging
Link ID: 18045 - Posted: 04.20.2013
A study by researchers at the National Institutes of Health gives insight into changes in the reward circuitry of the brain that may provide resistance against cocaine addiction. Scientists found that strengthening signaling along a neural pathway that runs through the nucleus accumbens — a region of the brain involved in motivation, pleasure, and addiction — can reduce cocaine-seeking behavior in mice. Research suggests that about 1 in 5 people who use cocaine will become addicted, but it remains unclear why certain people are more vulnerable to drug addiction than others. “A key step in understanding addiction and advancing treatment is to identify the differences in brain connectivity between subjects that compulsively take cocaine and those who do not,” said Ken Warren, Ph.D., acting director of the National Institute on Alcohol Abuse and Alcoholism (NIAAA). Researchers at NIAAA, part of NIH, conducted the study. “Until now, most efforts have focused on finding traits associated with vulnerability to develop compulsive cocaine use. However, identifying mechanisms that promote resilience may prove to have more therapeutic value,” said the paper’s senior author, Veronica Alvarez, Ph.D., acting chief of the Section on Neuronal Structure in the NIAAA Laboratory for Integrative Neuroscience. The study is available on the Nature Neuroscience website ahead of print. In the study, mice were conditioned to receive an intravenous dose of cocaine each time they poked their nose into a hole in their enclosure. Cocaine was then made unavailable for periods of time during the day. Some of the mice would stop seeking the drug once it was removed while others would obsessively continue to poke the hole in an effort to obtain the drug.
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 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
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
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.
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.”
by Sara Reardon The Brain Activity Map project launched recently by President Obama – and funded to the tune of $100 million in the US budget announcement earlier this month – highlights the need for research that focuses both on how individual neurons work and the ways that different regions of the brain work together as a unit. Looking at individual neurons requires slicing up brains into thin sections. However, this damages the axons – the arms that protrude from neurons to make connections with other cells – making it difficult to see exactly how brain cells link up. A few microscopic techniques can focus light deep into the intact brains of dead animals to study its structure without damaging the axons, but much of this light is scattered away by the fatty lipid membranes that surround individual cells, making the technique less than perfect. Now Kwanghun Chung, Karl Deisseroth and their team at Stanford University in California have developed a technique that provides a clearer picture. First, they remove the brain from a mouse and infuse it with a see-through gel that collects in the neurons' lipid membranes. As the gel solidifies, it takes the shape of the membranes and creates a matrix that holds the cells' proteins, DNA and RNA in place. Then the team adds a second chemical that dissolves the lipids, leaving a transparent brain made out of gel that retains the brain's proteins, DNA and RNA in their original positions. © Copyright Reed Business Information Ltd.
Keyword: Brain imaging
Link ID: 18018 - Posted: 04.11.2013
By JAMES GORMAN Scientists at Stanford University reported on Wednesday that they have made a whole mouse brain, and part of a human brain, transparent so that networks of neurons that receive and send information can be highlighted in stunning color and viewed in all their three-dimensional complexity without slicing up the organ. Even more important, experts say, is that unlike earlier methods for making the tissue of brains and other organs transparent, the new process, called Clarity by its inventors, preserves the biochemistry of the brain so well that researchers can test it over and over again with chemicals that highlight specific structures and provide clues to past activity. The researchers say this process may help uncover the physical underpinnings of devastating mental disorders like schizophrenia, autism, post-traumatic stress disorder and others. The work, reported on Wednesday in the journal Nature, is not part of the Obama administration’s recently announced initiative to probe the secrets of the brain, although the senior author on the paper, Dr. Karl Deisseroth at Stanford, was one of those involved in creating the initiative and is involved in planning its future. Dr. Thomas Insel, director of the National Institute of Mental Health, which provided some of the financing for the research, described the new work as helping to build an anatomical “foundation” for the Obama initiative, which is meant to look at activity in the brain. Dr. Insel added that the technique works in a human brain that has been in formalin, a preservative, for years, which means that long-saved human brains may be studied. “Frankly,” he said, “that is spectacular.” © 2013 The New York Times Company
Keyword: Brain imaging
Link ID: 18017 - Posted: 04.11.2013
By Scicurious In his State of the Union this year, President Obama referred to increasing support for science and technology, and mentioned the “Brain Activity Map”. Of course neuroscientists were instantly atwitter. It was the first we’d all heard of any Brain Activity Map. What is it? What did it mean? After a lot of speculation and some quickly formed opinions about whether or not it was a good idea…the White House has now unveiled what the project actually is: BRAIN, Brain Research through Advancing Innovative Neurotechnologies. And what is the project exactly? Will the BRAIN project end up as a BAM (Brain Activity Map)? Or a BUST (Badly Underfunded S**T)? I’d like to explore what I know, and I’d like to hear what everyone else knows as well. Am I wrong? Am I too optimistic? Too pessimistic? Have at. What is the BRAIN Project about? What are its goals? Well, nobody knows, actually. I certainly don’t know. But it appears that no one else knows either. “This working group, co-chaired by Dr. Cornelia “Cori” Bargmann (The Rockefeller University) and Dr. William Newsome (Stanford University), is being asked to articulate the scientific goals of the BRAIN initiative and develop a multi-year scientific plan for achieving these goals, including timetables, milestones, and cost estimates.” So basically, BRAIN is a very fancy initiative, with a fancy name…and so far, no goals. And of course, we’re all excited and trying to figure out what it’s going to be and whether or not it will work. Maybe it would have been in the better interest of the White House to wait until there were…you know, goals. But there is one goal that seems established here: new technologies. © 2013 Scientific American
Keyword: Brain imaging
Link ID: 18004 - Posted: 04.09.2013
By Sara Reardon and Bob Holmes, When President Obama called for $100 million in federal funding last week to map the human brain, he said he was hoping to “unlock the mystery of the three pounds of matter that sits between our ears.” Scientists hope that tracking brain activity neuron by neuron — an effort now called the Brain Research Through Advancing Innovative Neurotechnologies (BRAIN) Initiative — will revolutionize our understanding of brain function in the same way that the Human Genome Project is transforming our understanding of our genes. But just how do you go about mapping a brain? This is a question that two projects with similar lofty goals are already grappling with. The Human Brain Project aims to do it by creating a computer simulation of the entire brain. The Human Connectome Project is using magnetic resonance imaging to track the fibers that connect different regions of the brain on the millimeter scale, giving a rough-grained road map of the brain. To succeed, researchers will need to find noninvasive ways to record the firing of individual neurons, because all current methods involve opening the skull and, often, sticking electrodes into brain tissue. “Right now, you’re literally driving posts into the brain. It’s not very sophisticated,” says neurobiologist John Ngai of the University of California at Berkeley. A few groups are working on new approaches. The MindScope project at the Allen Institute for Brain Science in Seattle aims to map the visual cortex of mice. The team identifies where neurons are firing by injecting the brain with dyes or using genetically engineered proteins that bind to calcium molecules. When a neuron fires, calcium flows into the cell and activates the dye or protein. © 1996-2013 The Washington Post
Keyword: Brain imaging
Link ID: 18003 - Posted: 04.09.2013
By Rachel Ehrenberg A computer can decode the stuff of dreams. By comparing brain activity during sleep with activity patterns collected while study participants looked at certain objects, a computer learned to identify some contents of people’s unconscious reveries. “It’s striking work,” says cognitive psychologist Frank Tong of Vanderbilt University in Nashville, who was not involved in the research. “It’s a demonstration that brain activity during dreaming is very similar to activity during wakefulness.” The work, reported April 4 in Science by Japanese researchers led by Yukiyasu Kamitani of Advanced Telecommunications Research Institute International, adds to somewhat scant knowledge of how the brain constructs dreams, says Tong. The research could lead to a better understanding of what the brain does during different states of consciousness, such as those experienced by some coma patients. Dreams are a bit of a black box and difficult to study. Experiments with mice have revealed aspects of sleep and dreaming, such as how the experiences contribute to forming memories. But a mouse can’t tell you what it dreamed about. And the sleep stage that’s richest in dreams — REM sleep — typically kicks in about 90 minutes after a person conks out, making it time consuming to gather data on dreams. The noisy fMRI brain scanning machine doesn’t help. To skirt these experimental issues, the researchers recorded brain activity in three adult male volunteers during the early stages of sleep. After the subjects had dozed off, they were repeatedly awakened and asked for detailed reports on what they had seen while sleeping. In an example, one participant stated: “Well, there were persons, about three persons, inside some sort of hall. There was a male, a female and maybe like a child. Ah, it was like a boy, a girl and a mother. I don't think that there was any color.” © Society for Science & the Public 2000 - 2013
by Emily Underwood For neuroscientist Rafael Yuste, sitting in an ornate White House chamber yesterday listening to President Barack Obama heap praise—and some $100 million—on a brain-mapping initiative that he helped hatch was a "luminous" experience. "It felt like history," says the researcher, who works at Columbia University. "There is this enormous mystery waiting to be unlocked," Obama told the East Room crowd packed with leaders of American neuroscience during a 12-minute paean to brain research (likely the most expansive yet delivered by an American president). By "giving scientists the tools they need to get a dynamic picture of the brain in action," he said, the new initiative will help scientists find a cure for complex brain processes such as traumatic brain injury and Parkinson's, and create jobs that "we haven't even dreamt up yet." For all the lofty rhetoric, however, the White House didn't provide many details about how the BRAIN (Brain Research through Advancing Innovative Neurotechnologies) Initiative will accomplish its mission. And the lack of detail is worrying not only BRAIN skeptics—who argue that it targets the wrong goal and could detract from other research efforts—but also even some staunch advocates such as Yuste. The way that the White House has packaged and plans to fund and coordinate the initiative, they say, is creating some unease. "As the proposal stands, it's still awfully vague, so it's hard not to have some reservations," says biophysicist Jeremy Berg of the University of Pittsburgh in Pennsylvania, who is a former director of the National Institute of General Medical Sciences at the National Institutes of Health (NIH). © 2010 American Association for the Advancement of Science
Keyword: Brain imaging
Link ID: 17990 - Posted: 04.05.2013