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; Aggression
Link ID: 18024 - 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; Aggression
Link ID: 18020 - Posted: 04.11.2013

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

Keyword: Sleep; Aggression
Link ID: 17995 - Posted: 04.05.2013

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

Dana Smith In January, the European Commission pledged 500 million euros to work towards creating a functional model of the human brain. Then, yesterday, Barack Obama officially announced an initiative to advance neuroscience, funding a large-scale research project aimed at unlocking the secrets of the brain that involves over $100 million in federal spending in the first year alone, as well as investments from private organizations. Both projects are geared towards creating a working model of the brain, mapping its 100 billion neurons. The first, the Human Brain Project, is being spearheaded by Professor Henry Markram of École Polytechnique Fédérale de Lausanne. Together with collaborators from 86 other European institutions, they aim to simulate the workings of the human brain using a giant super computer. This would mean compiling information about the activity of individual neurons and neuronal circuits throughout the brain in a massive database. They then hope to integrate the biological actions of these neurons to create theoretical maps of different subsystems, and eventually, through the magic of computer simulation, a working model of the entire brain. Neurologic and psychiatric disorders collectively "affect 100 million Americans and cost us $500 billion each year in terms of health-care costs." Similarly, the United States' recently renamed Brain Research Through Advancing Innovative Neurotechnologies, or BRAIN (previously the Brain Activity Map Project, or BAM), is an initiative that will be organized through the National Institutes of Health, National Science Foundation, and Defense Advanced Research Projects Agency, and carried out in a number of universities and research institutes throughout the U.S. © 2013 by The Atlantic Monthly Group.

Keyword: Brain imaging
Link ID: 17989 - Posted: 04.05.2013

By Puneet Kollipara President Barack Obama has unveiled a long-term neuroscience research initiative that will develop new tools and technologies to study human and animal brains on larger scales than currently possible. Announced April 2, the BRAIN Initiative could ultimately help researchers better understand human behavior and thought and develop new ways to diagnose, treat and cure neurological and psychiatric diseases. The initiative is slated to begin in October, with $100 million budgeted for the project in fiscal year 2014. The National Institutes of Health, the Defense Advanced Research Projects Agency and the National Science Foundation will lead the effort, which Obama likened to the Human Genome Project in terms of its ambitious aims and the scientific and health benefits the initiative could yield. The human brain remains one of the greatest scientific mysteries. Researchers can now probe only a small number of neurons simultaneously or get relatively crude looks at specific regions or the entirety of the brain. But scientists believe that understanding the action of circuits containing thousands or millions of coordinated neurons could lead to a better understanding of how the brain works — as well as what goes wrong when it doesn’t. Short for Brain Research through Advancing Innovative Neurotechnologies, the BRAIN Initiative would seek to develop tools and technologies to measure and manipulate the firing patterns of all neurons in a circuit. Other new tools — hardware, software and databases — would store the data, make it public and analyze it. The initiative takes its inspiration from a research vision known as the Brain Activity Map, which originated from a group of neuroscientists, nanoscientists and research groups. © Society for Science & the Public 2000 - 2013

Keyword: Brain imaging
Link ID: 17984 - Posted: 04.03.2013

By John McCarthy Maybe this discovery is interesting because it sheds therapeutic light on the dreaded neurodegenerative diseases that killed Woody Guthrie and Lou Gehrig. Or maybe it’s fascination with healthy cells, and yet another unsuspected complexity in how they work. What’s discovered: a previously unknown energy source in nerve cells. It propels the molecular “motors” that drag neurotransmitters from the nucleus where they’re made. The “motors” are assemblies of molecules. They walk like clumsy robots, with a staggering gait, dragging a capsule of neurotransmitter “bullets” along microtubule “highways” between nucleus and synapses. They move by flinging their boot-like feet (lavender blobs, in the image) forward, a billionth of a meter at each step. (A superb animation of “motors” in action is XVIVO’s “Life of a Cell” (at ~1:15 of playing time)). When the cargo finally arrives at the synapses, neurotransmitters are loaded into compartments at the synapse’s interior face, like bullets into a magazine. They are ready to be “fired” across a synapse to signal an adjoining neuron. It’s this transport of neurotransmitter “bullets” that failed in Guthrie’s and Gehrig’s nerve cells. Their synapses had nothing to fire. What powers the flinging that moves those boots? Previously, the answer has been specialized molecules (acronym: ATP) spewed into the cell’s fluid interior by mitochondria. The boots, it was thought, powered each step by grabbing a floating ATP and blowing it up like a firecracker. © 2013 Scientific American

Keyword: Huntingtons
Link ID: 17978 - Posted: 04.02.2013

Regina Nuzzo In a twist that evokes the dystopian science fiction of writer Philip K. Dick, neuroscientists have found a way to predict whether convicted felons are likely to commit crimes again from looking at their brain scans. Convicts showing low activity in a brain region associated with decision-making and action are more likely to be arrested again, and sooner. Kent Kiehl, a neuroscientist at the non-profit Mind Research Network in Albuquerque, New Mexico, and his collaborators studied a group of 96 male prisoners just before their release. The researchers used functional magnetic resonance imaging (fMRI) to scan the prisoners’ brains during computer tasks in which subjects had to make quick decisions and inhibit impulsive reactions. The scans focused on activity in a section of the anterior cingulate cortex (ACC), a small region in the front of the brain involved in motor control and executive functioning. The researchers then followed the ex-convicts for four years to see how they fared. Among the subjects of the study, men who had lower ACC activity during the quick-decision tasks were more likely to be arrested again after getting out of prison, even after the researchers accounted for other risk factors such as age, drug and alcohol abuse and psychopathic traits. Men who were in the lower half of the ACC activity ranking had a 2.6-fold higher rate of rearrest for all crimes and a 4.3-fold higher rate for nonviolent crimes. The results are published today in the Proceedings of the National Academy of Sciences1. © 2013 Nature Publishing Group

Keyword: Aggression; Aggression
Link ID: 17950 - Posted: 03.26.2013

By John Horgan Does anyone still remember “The Decade of the Brain“? Youngsters don’t, but perhaps some of my fellow creaky, cranky science-lovers do. In 1990, the brash, fast-growing Society for Neuroscience convinced Congress to name the ’90s the Decade of the Brain. The goal, as President George Bush put it, was to boost public awareness of and support for research on the “three-pound mass of interwoven nerve cells” that serves as “the seat of human intelligence, interpreter of senses and controller of movement.” One opponent of this public-relations stunt was Torsten Wiesel, who won a Nobel Prize in 1981 for work on the neural basis of vision. When I interviewed him in 1998 for my book The Undiscovered Mind, he grumbled that the Decade of the Brain was “foolish.” Scientists “need at least a century, maybe even a millennium,” to understand the brain, Wiesel said. “We are at the very beginning of brain science.” I recalled Wiesel’s irritable comments as I read about big new neuroscience initiatives in the U.S. and Europe. In January, the European Union announced it would sink more than $1 billion over the next decade into the Human Brain Project, an attempt to construct a massive computer simulation of the brain. The project, according to The New York Times, involves more than 150 institutions. Meanwhile, President Barack Obama is reportedly planning to commit more than $3 billion to a similar project, called the Brain Activity Map. © 2013 Scientific American

Keyword: Brain imaging
Link ID: 17943 - Posted: 03.25.2013

By Meghan Rosen Shushing neural chitchat in mouse brains can spark schizophrenia-like symptoms, a new study suggests. The findings are the first to demonstrate — at least in mice — that curbing communication among neurons in certain parts of the brain can cause some of the cognitive problems associated with schizophrenia. By muzzling neurons in the mediodorsal thalamus, or MD — a cell cluster that sends signals to the brain’s outer layer — researchers hindered mouse memory and learning in much the same way that schizophrenia seems to do in humans, scientists report March 20 in Neuron. Cognitive problems in schizophrenia have long been a mystery to scientists and a troubling symptom for people with the condition. The findings suggest that the problems stem from the thalamus, says neuropsychologist Neil Woodward of Vanderbilt University in Nashville, who was not involved with the new work. People with schizophrenia suffer from a range of debilitating symptoms: hallucinations, delusions and social disorders, says study coauthor Christoph Kellendonk of Columbia University. Patients also have problems with short-term memory and learning. Unlike other symptoms, these cognitive problems have been nearly impossible to treat. Brain imaging of people with schizophrenia had previously linked cognitive defects to changes in the MD — part of a walnut-sized chunk of gray matter snuggled above the brain stem. Normally, the MD relays information to and from the prefrontal cortex, the brain region behind the forehead that controls complex thought. In people with schizophrenia, the imaging showed, the MD is unusually quiet. © Society for Science & the Public 2000 - 2013

Keyword: Schizophrenia; Aggression
Link ID: 17929 - Posted: 03.23.2013

by Sara Reardon When she returned from serving in the Gulf conflict in 1991, US Air Force nurse Denise Nichols experienced sudden aches, fatigue and cognitive problems, but had no idea 'what was causing them. They grew worse: even helping her daughter with multiplication tables became difficult, she says, and eventually she had to quit her job. Nichols wasn't alone. About a third of Gulf war veterans – possibly as many as 250,000 – returned with a similar set of symptoms. Now an imaging study has found that these veterans have what appear to be unique structural changes in the wiring of their brains. This fits with the scientific consensus that Gulf War syndrome (GWS) is a physical condition rather than a psychosomatic one, and should be treated with painkilling drugs instead of counselling. The military in various countries has in the past consistently denied that there is a physical basis to GWS. Although the US Department of Veterans Affairs (VA) now officially accepts that the disorder is physical, the issue has been mired in controversy. Earlier this month, Steven Coughlin, a former senior epidemiologist at the VA, testified to a Congressional panel that the VA had suppressed and manipulated research data so as to suggest that the disorder was psychosomatic. © Copyright Reed Business Information Ltd.

Keyword: Stress; Aggression
Link ID: 17928 - Posted: 03.23.2013

Monya Baker At first glance, it looks like an oddly shaped campfire: smoky grey shapes light up with red sparks and flashes. But the video actually represents a different sort of crackle — the activity of individual neurons across a larval fish brain. It is the first time that researchers have been able to image an entire vertebrate brain at the level of single cells. “We see the big picture without losing resolution,” says Phillipp Keller, a microscopist at the Howard Hughes Medical Institute's Janelia Farm Research Campus in Ashburn, Virginia, who developed the system with Janelia neurobiologist Misha Ahrens. The researchers are able to record activity across the whole fish brain almost every second, detecting 80% of its 100,000 neurons. (The rest lie in hard-to-access areas, such as between the eyes; their activity is visible but cannot be pinned down to single cells.) The work is published today in Nature Methods1. “It’s phenomenal,” says Rafael Yuste, a neuroscientist at Columbia University in New York. “It is a bright star now in the literature, suggesting that it is not crazy to map every neuron in the brain of an animal.” Yuste has been leading the call for a big biology project2 that would do just that in the human brain, which contains about 85,000 times more neurons than the zebrafish brain. The resolution offered by the zebrafish study will enable researchers to understand how different regions of the brain work together, says Ahrens. With conventional techniques, imaging even 2,000 neurons at once is difficult, so researchers must pick and choose which to look at, and extrapolate. Now, he says, “you don't need to guess what is happening — you can see it”. © 2013 Nature Publishing Group

Keyword: Brain imaging
Link ID: 17922 - Posted: 03.19.2013

By TIM REQUARTH For months, Henry Markram and his team had been feeding data into a supercomputer, four vending-machine-size black boxes whirring quietly in the basement of the Swiss Federal Institute of Technology in Lausanne. The Blue Brain computer has 10,000 virtual neurons. The colors represent the neurons' electric voltage at a specific moment. The boxes housed thousands of microchips, each programmed to act like a brain cell. Cables carried signals from microchip to microchip, just as cells do in a real brain. In 2006, Dr. Markram flipped the switch. Blue Brain, a tangled web of nearly 10,000 virtual neurons, crackled to life. As millions of signals raced along the cables, electrical activity resembling real brain waves emerged. “That was an incredible moment,” he said, comparing the simulation to what goes on in real brain tissue. “It didn’t match perfectly, but it was pretty good. As a biologist, I was amazed.” Deciding then that simulating the entire brain on a supercomputer would be possible within his lifetime, Dr. Markram, now 50, set out to prove it. That is no small feat. The brain contains nearly 100 billion neurons organized into networks with 100 trillion total connections, all firing split-second spikes of voltage in a broth of complex biological molecules in constant flux. In 2009, Dr. Markram conceived of the Human Brain Project, a sprawling and controversial initiative of more than 150 institutions around the world that he hopes will bring scientists together to realize his dream. © 2013 The New York Times Company

Keyword: Brain imaging; Aggression
Link ID: 17921 - Posted: 03.19.2013

By Ben Thomas In 1956, a legion of famed scientific minds descended on Dartmouth College to debate one of mankind’s most persistent questions: Is it possible to build a machine that thinks? The researchers had plenty to talk about – biologists and mathematicians had suggested since the 1940s that nerve cells probably served as binary logic gates, much like transistors in computer mainframes. Meanwhile, computer theorists like Alan Turing and Claude Shannon had been arguing for years that intelligence and learning could – at least in theory – be programmed into a machine of sufficient complexity. Within the next few decades, many researchers predicted, we’d be building machines capable of conscious thought. Fifty-odd years after that first Dartmouth Conference, our sharpest supercomputers still struggle to hold basic conversations. We’ve created software that can drive our cars and predict our purchases, but the dreams of a true artificial brain – and of a working neuron-by-neuron model of the human brain itself – look even more distant than they did in the 1950s. The more we learn about how the brain works, the more interwoven and inextricable we realize its components and processes are – and the less like a computer it seems. Take synapses, for example – the points where neurons link up and exchange information. Neuroscientists estimate that a human brain may contain about 150 trillion of them, and no two are quite identical – either to one another, or to any synapse in anyone else’s brain. On top of this complexity, every neuron in a brain is constantly learning, adapting, fine-tuning its sensitivity, tinkering with its synaptic connections – rarely wired the same way from one day to the next. In light of all this, it’s not hard to see why many scientists seriously doubt that we’ll map an entire human brain any time this century – much less engineer a digital version from scratch. © 2013 Scientific American

Keyword: Brain imaging
Link ID: 17920 - Posted: 03.19.2013

By Charles Q. Choi and Txchnologist Scientists scanning the human brain can now tell whom a person is thinking of, the first time researchers have been able to identify what people are imagining from imaging technologies. Work to visualize thought is starting to pile up successes. Recently, scientists have used brain scans to decode imagery directly from the brain, such as what number people have just seen and what memory a person is recalling. They can now even reconstruct videos of what a person has watched based on their brain activity alone. Cornell University cognitive neuroscientist Nathan Spreng and his colleagues wanted to carry this research one step further by seeing if they could deduce the mental pictures of people that subjects conjure up in their heads. “We are trying to understand the physical mechanisms that allow us to have an inner world, and a part of that is how we represent other people in our mind,” Spreng says. His team first gave 19 volunteers descriptions of four imaginary people they were told were real. Each of these characters had different personalities. Half the personalities were agreeable, described as liking to cooperate with others; the other half were less agreeable, depicted as cold and aloof or having similar traits. In addition, half these characters were described as outgoing and sociable extroverts, while the others were less so, depicted as sometimes shy and inhibited. The scientists matched the genders of these characters to each volunteer and gave them popular names like Mike, Chris, Dave or Nick, or Ashley, Sarah, Nicole or Jenny. © 2013 Scientific American

Keyword: Brain imaging; Aggression
Link ID: 17906 - Posted: 03.15.2013

By Rachel Ehrenberg Surgeons have replaced 75 percent of a man’s skull with a custom-designed polymer cranium constructed with a 3-D printer. The surgery took place on March 4 and is the first U.S. case following the FDA’s approval of the implants last month. The patient’s reason for needing such extensive replacement surgery has not been revealed. Similar surgeries may follow in other cases where sections of the skull are removed because the brain has swollen during a surgery or after an accident, says Scott DeFelice, president of Connecticut-based Oxford Performance Materials, the company that created the prosthetic. Technicians used CT scans to get images of the part of the skull that needed replacing. Then, with computer software and input from surgeons, engineers designed the replacement part. A machine that uses lasers to fuse granules of material built the prosthetic layer by layer out of a special plastic called PEKK. While inert like titanium, PEKK is riddled on its surface with pocks and ridges that promote bone cell growth, DeFelice says. Such implants have value as a brain-protecting material, says Jeremy Mao, a biomedical engineer and codirector of Columbia University’s center for craniofacial regeneration. But doctors will need to keep an eye out for long-term problems; The skull isn’t just a box for the brain but a complicated piece of anatomy linked to connective and soft tissues. © Society for Science & the Public 2000 - 2013

Keyword: Robotics
Link ID: 17891 - Posted: 03.12.2013