By Jason G. Goldman The largest fish in the ocean is the whale shark (Rhincodon typus). This massive, migratory fish can grow up to twelve meters in length, but its enormous mouth is designed to eat the smallest of critters: plankton. While the biggest, the whale shark isn’t the only gigantic filter-feeding shark out there: the basking shark and the megamouth shark also sieve enormous amounts of the tiny organisms from the sea in order to survive. While scientists like Al Dove and Craig McClain (of Deep Sea News) are learning more and more about the basic biology and behavior of these magnificent creatures, other scientists are busy investigating their neuroanatomy. A few years ago, Kara E. Yopak and Lawrence R. Frank from the University of California in San Diego got their hands on two whale shark brains from an aquarium, and put them into an MRI scanner. But they weren’t just interested in imaging the brains of the whale sharks. What they wanted to know was how the organization of whale shark brains compared to the brains of other shark species for which scientists had previously obtained neuroanatomical data. Would the brains of two species be more similar if they shared a recent evolutionary ancestor, and were therefore more genetically related? Or would shark brains be more similar among species that shared a similar lifestyle, such as those that patrol the middle and surface of the water column (pelagic sharks, such as the great white, oceanic whitetip, blue, mako, and whale sharks) versus those that live along the sea floor (benthic sharks, such as the nurse and cat sharks). Or perhaps the brains of sharks would be grouped according to their habitat, such as those that live in coastal waters, around reefs, or in the open ocean. Maybe sharks brains ought to be grouped according to behavioral specialization, such as hunting methods. Answers to these questions could shed some important light on brain evolution, both in sharks as well as more generally. © 2012 Scientific American

Keyword: Evolution; Aggression
Link ID: 17180 - Posted: 08.18.2012

by Molly Docherty The brain drain is real. There is a network of previously unrecognised vessels that rid the brain of unwanted extracellular fluids and other substances, including amyloid-beta – a peptide that accumulates in the brain of people with Alzheimer's. The new discovery looks set to add to our understanding of the disease. Jeffrey Iliff at the University of Rochester Medical Center, New York, and his colleagues, were intrigued by the fact that there are no obvious lymphatic vessels in the brain. Among other things, the lymphatic system removes waste interstitial fluids from body tissue. "It seemed strange that such an important and active organ wouldn't have a specialised waste-removal system," says Iliff. When the researchers added fluorescent and radioactive tracers to the cerebrospinal fluid of live mice, the tracers quickly spread throughout the rodents' brains. Using two-photon microscopy to visualise the movement in real-time, the team saw cerebrospinal fluid permeating the entire brain through 'pipes' surrounding blood vessels, similar to the lymphatic system that services all other organs. The pipes work on hydraulic principles, though, and so the system breaks upon opening, making it hard to identify it outside living organisms. © Copyright Reed Business Information Ltd.

Keyword: Brain imaging
Link ID: 17174 - Posted: 08.16.2012

By Katherine Harmon Jill, a 60-year-old woman in Milwaukee, has overcome extreme poverty. So, now that she has enough money to put food in the fridge, she fills it. She also fills her freezer, her cupboard and every other corner of her home. “I use duct tape to close the freezer door sometimes when I’ve got too many things in there,” she told A&E’s Hoarders. Film footage of her kitchen shows a cat scrambling over a rotten grapefruit; her counters—and most surfaces in her home—seemed to be covered with several inches of clutter and spoiled food. “I was horrified,” her younger sister said after visiting Jill. And the landlord threatened eviction because the living conditions became unsafe. Jill joins many others who have been outed on reality TV as a “hoarder.” We might have once called people with these tendencies “collectors” or “eccentrics.” But in recent years, psychiatrists had suggested they have a specific type of obsessive-compulsive disorder (OCD). A movement is underfoot, however, for the new edition of the psychiatric field’s diagnostic bible (the fifth edition of the Diagnostic and Statistical Manual of Mental Disorders, or DSM-5), to move hoarding disorder to its own class of illness. And findings from a new brain scan study, published online August 6 in Archives of General Psychiatry, support this new categorization. Hoarding disorder is categorized as “the excessive acquisition of and inability to discard objects, resulting in debilitating clutter,” wrote the researchers behind the new study, led by Yale University School of Medicine’s David Tolin. © 2012 Scientific American,

Keyword: OCD - Obsessive Compulsive Disorder; Aggression
Link ID: 17137 - Posted: 08.07.2012

Scientists have discovered a biological marker that may help to identify which depressed patients will respond to an experimental, rapid-acting antidepressant. The brain signal, detectable by noninvasive imaging, also holds clues to the agent’s underlying mechanism, which are vital for drug development, say National Institutes of Health researchers. The signal is among the latest of several such markers, including factors detectable in blood, genetic markers, and a sleep-specific brain wave, recently uncovered by the NIH team and grantee collaborators. They illuminate the workings of the agent, called ketamine, and may hold promise for more personalized treatment. "These clues help focus the search for the molecular targets of a future generation of medications that will lift depression within hours instead of weeks," explained Carlos Zarate, M.D., of the NIH’s National Institute of Mental Health (NIMH). "The more precisely we understand how this mechanism works, the more narrowly treatment can be targeted to achieve rapid antidepressant effects and avoid undesirable side effects." Previous research had shown that ketamine can lift symptoms of depression within hours in many patients. But side effects hamper its use as a first-line medication. So researchers are studying its mechanism of action in hopes of developing a safer agent that works similarly. Ketamine works through a different brain chemical system than conventional antidepressants. It initially blocks a protein on brain neurons, called the NMDA receptor, to which the chemical messenger glutamate binds.

Keyword: Depression; Aggression
Link ID: 17124 - Posted: 08.04.2012

By Melissa Healy Los Angeles Times Measuring human intelligence may be controversial and oh-so-very-tricky to do. But like obscenity, we think we know it when we see it. A new study, however, demonstrates a more rigorous way to see and measure differences in intelligence between individuals. It finds that connectedness among the brain's disparate regions is a key factor that separates the plodding from the penetrating. As many researchers have long suspected, intelligence does have a "seat" in the human brain: an area just behind each of the temples called the lateral prefrontal cortex. But researchers writing in the journal Neuroscience found that human behavior that is exceptionally flexible, responsive and capable of navigating complexity requires something beyond a strong and active prefrontal cortex: strong and agile runners must link that seat to brain regions involved in perception, memory, language and mobility. The researchers estimate that the strength of those connections, as measured when subjects rested between mental tasks, explains about 10% of differences in intelligence among individuals. That makes this measure an even better predictor of intelligence than brain size -- a measure that scientists believe may explain about 7% of the variation in intelligence among individuals. To detect this relationship, the Neuroscience study compared functional magnetic resonance imaging (fMRI) brain scans of 78 men and women between 18 and 40 years old with those subjects' performance on tests of cognitive performance that required "fluid intelligence" and "cognitive control." Subjects, for instance, were asked to count backwards by, say, nine, or to watch a series of visual images and then indicate whether a single image shown had been among them. Copyright 2012

Keyword: Intelligence; Aggression
Link ID: 17117 - Posted: 08.04.2012

Monya Baker Last week, the Sacramento Bee reported that two neurosurgeons at the University of California, Davis, had been banned from research on humans after deliberately infecting three terminally ill cancer patients with pathogenic bacteria in an attempt to treat them. All three died, two showing complications from the infection. Nature explores what happened and the science behind it. Who authorized the researchers to infect the patients? All three patients consented to infection. However, anyone testing experimental drugs in the United States requires approval from their university’s Institutional Review Board (IRB) and oversight by the country's Food and Drug Administration (FDA), both of which review evidence for safety and efficacy. Neurosurgeons Paul Muizelaar and Rudolph Schrot at the University of California (UC), Davis, did not obtain this approval; they say they did not think it was required. Harris Lewin, the vice-chancellor of research at UC Davis, wrote a letter to the FDA describing what had occurred as “serious and continuing noncompliance”. In 2008, working under instructions from Muizelaar, Schrot asked the FDA about the possibility of deliberately infecting a postoperative wound in a particular patient with glioblastoma with the bacterium Enterobacter aerogenes. He was told that animal studies were needed first. Muizelaar did not infect that patient, but arranged for a graduate student to begin tests in rats. Although bacteria were purchased as research materials not to be used in humans, they were eventually used in three other patients with glioblastoma. © 2012 Nature Publishing Group

Keyword: Neuroimmunology; Aggression
Link ID: 17097 - Posted: 07.28.2012

By Sandra Upson All elite athletes train hard, possess great skills and stay mentally sharp during competition. But what separates a gold medalist from an equally dedicated athlete who comes in 10th place? A small structure deep in the brain may give winners an extra edge. Recent studies indicate that the brain's insular cortex may help a sprinter drive his body forward just a little more efficiently than his competitors. This region may prepare a boxer to better fend off a punch his opponent is beginning to throw as well as assist a diver as she calculates her spinning body's position so she hits the water with barely a splash. The insula, as it is commonly called, may help a marksman retain a sharp focus on the bull's-eye as his finger pulls back on the trigger and help a basketball player at the free-throw line block out the distracting screams and arm-waving of fans seated behind the backboard. The insula does all this by anticipating an athlete's future feelings, according to a new theory. Researchers at the OptiBrain Center, a consortium based at the University of California, San Diego, and the Naval Health Research Center, suggest that an athlete possesses a hyper-attuned insula that can generate strikingly accurate predictions of how the body will feel in the next moment. That model of the body's future condition instructs other brain areas to initiate actions that are more tailored to coming demands than those of also-rans and couch potatoes. This heightened awareness could allow Olympians to activate their muscles more resourcefully to swim faster, run farther and leap higher than mere mortals. In experiments published in 2012, brain scans of elite athletes appeared to differ most dramatically from ordinary subjects in the functioning of their insulas. © 2012 Scientific American

Keyword: Brain imaging
Link ID: 17088 - Posted: 07.25.2012

Rebecca Goldin, Ph.D., Cindy S. Merrick With the news media telling us that neuroscience – and brain scans – can explain everything from a global pandemic of Justin Bieber fever to whether you are likely to stay with your spouse, we investigate what neuroscience can and can’t tell us about who we are and why we do the things we do. In the first part of an ongoing series, we look at functional magnetic resonance imaging, and whether it’s really the window on the mind that some in the media – and science – would have us believe. Gone are the days when the only people who believed in technologies that could read minds were distinguishable from the rest of us by their tin foil hats. With the advent of functional magnetic resonance imaging (fMRI), we are able to see, in near-video quality, the ebb and flow of a live mind at work. Or so it seems. Something, for certain, is at work, and there are lots of people willing to tell you they know exactly how to interpret what we can see. Certainly this new technology has already produced fascinating results: surgeons use it real-time to avoid critical regions while operating on brain tumors; physicians use it to look for changes in the brain activity of stroke victims as they experience physical rehabilitation; and fMRI data showing activity in the brains of patients thought to be in a vegetative state may be blurring the line that defines consciousness. Along with these advances, though, have appeared many somewhat less credible stories. The media reports claims ranging from fMRI’s ability to detect lies to its predicting future addictive behavior or determining whether or not you really love your spouse, or, maybe, your iPhone. Already, attempts have been made to use fMRI as admissible evidence of lie detection in court (so far, they have failed); and in another court case, fMRI results and a neuroscientist’s testimony were admitted in the sentencing hearing. The data were used as evidence that the defendant, a violent offender, was psychopathic.

Keyword: Brain imaging
Link ID: 17047 - Posted: 07.17.2012

Will Ferguson, reporter You can't visit this tropical jungle. It's a forest of neurons snaking through a pig's brain. The brain cells, enlarged and coloured here, are being investigated to give scientists a clearer view of the mechanics of brain matter when it is hit hard. Michel Destrade, an applied mathematician at the National University of Ireland, Galway, and colleagues obtained samples of pig brains from a local slaughterhouse to study the mechanics of brain matter undergoing rapid impacts. With the aim of improving the treatment of traumatic head injuries, they used the samples to create computer models of electrical signals inside the brain. But during the course of the experiment, Destrade's student Badar Rashid decided to find out what white and grey matter inside a brain look like. He started with an image of neuron bundles taken using scanning electron microscopy, and blew it up to 4,000 times its actual size. He then added colour to the black and white result according to his own aesthetic. The image appears in Physics Today (DOI:10.1063/PT.3.1651). © Copyright Reed Business Information Ltd.

Keyword: Brain imaging
Link ID: 17042 - Posted: 07.16.2012

By Mahir Ozdemir Hardly a week passes without some sensational news about brain scans unleashing yet another secret of our cognitive faculties. Very recently I stumbled upon the news that according to recent research neuroscientists can tell, depending on your brain responses, whether you and your significant one will still be together in a few years: “You might hide it from friends and family. But you can’t hide it from neuroscientists”. The technique at the bottom of the study, just like the majority of studies making a big splash, is functional magnetic resonance imaging, fMRI. Researchers have been struggling to unfold ‘what’s under the hood’ through the lens of Neuroscience and they have been finding all sorts of insights into human behavior. They have been looking at everything from how multitasking is harder for seniors to how people love talking about themselves. Neural basis of love and hatred, compassion and admiration have all been studied with fMRI, yielding colored blobs representing the corresponding love or hatred centers in our brains. First a brief background: The fMRI technique measures brain activity indirectly via changes in blood oxygen levels in different parts of the brain as subjects participate in various activities. While lying down with head immobilized in a small confined chamber of the notoriously noisy MR scanner, subjects are shown experimental stimuli. They wear earplugs to reduce at least some part of the noise while performing these cognitive tasks. © 2012 Scientific American

Keyword: Brain imaging
Link ID: 17005 - Posted: 07.07.2012

By Daisy Yuhas At right is a picture of someone’s brain as seen through functional magnetic resonance imaging or fMRI. This particular subject is taxing his neurons with a working memory task—those sunny orange specks represent brain activity related to the task. fMRI images show the brain according to changes in blood oxygen level, a proxy for degree of mental activity. It’s a pretty amazing tool; it has validated a lot of assumptions about brain regions and helped us make comparisons between groups of people, shedding light on addiction, development and disease. Some scientists believe it can help us read minds (more on that later) or even predict the future. But fMRI doesn’t actually provide detail at the level of a cell. The 3-dimensionsal image it provides is built up in units called voxels. Each one represents a tidy cube of brain tissue—a 3-D image building block analogous to the 2-D pixel of computers screens, televisions or digital cameras. Each voxel can represent a million or so brain cells. Those orange blobs in the image above are actually clusters of voxels—perhaps tens or hundreds of them. fMRI is also too slow to capture all of the changes in the brain. Each scan requires a second or two, enough time for a neuron to fire more than a hundred times. That means it can’t provide a clear sense of precisely when things happen. Trying to explain whether activity in one spot causes activity in another is not possible through fMRI alone. Furthermore, you have to be careful with your conclusions. Just because voxels corresponding to one region ‘light up’ when your subject sees a terrifying tiger doesn’t mean that every time this region appears active, your subject is frightened. Many of the brain’s regions are quite complex and involved in multiple processes. © 2012 Scientific American

Keyword: Brain imaging
Link ID: 16957 - Posted: 06.23.2012

Neuroscientist and friend of the blog Bradley Voytek has a terrific piece about the relationship between popular science writing and neuroscience that’s well worth your time. In brief, he says, the primary problem are neuroscientists themselves. Or at least, some of the assumptions that neuroscientists make. The problem, he notes, is a problem that long term readers here are familiar with – the confusion of cause and effect, as well as an over-reductionist view of the brain. Namely, that imaging studies showing a portion of the brain “lighting up” when something happens means that that area of the brain is directly involved in the activity. Something that he analogizes to “like how when your arms swing faster when you run that means that your arms are ‘where running happens’.” Voytek also provides what I think is one of the best analogies I’ve read about the problem inherent in trying to isolate “which part of the brain does X”: Imagine asking “where is video located in my computer?” That doesn’t make any sense. Your monitor is required to see the video. Your graphics card is required to render the video. The software is required to generate the code for the video. But the “video” isn’t located anywhere in the computer. This is something that I think is exactly right. The best neuroscientists out there are, I think, very aware of this problem, but I think part of what’s going on here is the inherent limitations of our ability to experiment. Take fMRI’s, for example, which have provided an interesting look into what kinds of activity is going on in the brain while the person being imaged is doing or thinking something. It’s one of the best pieces of equipment available, but it’s very nature can be deceiving. Because it’s one of the few ways available to figure out what’s going on in the brain, it can be tempting to see what is measured by an fMRI image as definitive. 2012 Forbes.com LLC™

Keyword: Brain imaging
Link ID: 16927 - Posted: 06.19.2012

By AMANDA SCHAFFER In recent decades, there have been few new treatments for people with stubbornly high blood pressure. Exercise and a low-sodium diet, along with such stalwart drugs as diuretics, ACE inhibitors and beta-blockers, have made up the standard regimens. But these efforts fail in a surprising number of patients. On three or more medications, many still suffer from uncontrolled hypertension and with it a heightened risk of heart attack and stroke. Now, doctors are experimenting with an innovative but drastic new approach that may help lessen the danger in patients for whom nothing else works. During the procedure, called renal denervation, a physician threads a catheter into the arteries leading to the kidney, then delivers pulses of radio-frequency energy that interrupt the signaling in nerves to and from that organ. The damage to the nerves is probably permanent, although no one is certain. Small clinical trials, conducted mainly outside the United States, have suggested that in combination with drugs, renal denervation may help to reduce high blood pressure in patients with so-called treatment-resistant disease. The treatment is already available in Australia and Europe. The largest randomized controlled trial to date is now under way in the United States. It is sponsored by Medtronic, which hopes to win Food and Drug Administration approval for a specialized catheter and generator used in the procedure. © 2012 The New York Times Company

Keyword: Stress
Link ID: 16903 - Posted: 06.12.2012

A brain training technique which helps people control activity in a specific part of the brain could help treat depression, a study suggests. Cardiff University researchers used MRI scanners to show eight people how their brains reacted to positive imagery. After four sessions of the therapy the participants had seen significant improvements in their depression. Another eight who were asked to think positively but did not see brain images as they did so showed no change. The researchers said they believed the MRI scans allowed participants to work out, through trial and error, which sort of positive emotional imagery was most effective. The technique - known as neurofeedback - has already had some success in helping people with Parkinson's disease. But the team acknowledge that further research, involving a larger number of people, is needed to ascertain how effective the therapy is, particularly in the long term. Prof David Linden, who led the study which was published in the PLoS One journal, said it had the potential to become part of the "treatment package" for depression. About a fifth of people will develop depression at some point in their lives and a third of those will not respond to standard treatments. BBC © 2012

Keyword: Depression; Aggression
Link ID: 16888 - Posted: 06.09.2012

By Jane Dreaper Health correspondent, BBC News Multiple CT scans in childhood can triple the risk of developing brain cancer or leukaemia, a study suggests. The Newcastle University-led team examined the NHS medical records of almost 180,000 young patients. But writing in The Lancet the authors emphasised that the benefits of the scans usually outweighed the risks. They said the study underlined the fact the scans should only be used when necessary and that ways of cutting their radiation should be pursued. During a CT (computerised tomography) scan, an X-ray tube rotates around the patient's body to produce detailed images of internal organs and other parts of the body. In the first long-term study of its kind, the researchers looked at the records of patients aged under 21 who had CT scans at a range of British hospitals between 1985 and 2002. Because radiation-related cancer takes time to develop, they examined data on cancer cases and mortality up until 2009. The study estimated that the increased risk translated into one extra case of leukaemia and one extra brain tumour among 10,000 CT head scans of children aged under ten. BBC © 2012

Keyword: Brain imaging; Aggression
Link ID: 16883 - Posted: 06.07.2012

By Brian Alexander When news broke that singer Sheryl Crow has a benign brain tumor called a meningioma, her representative swatted away concern by saying that “half of us are walking around with [a meningioma] but you don’t really know unless you happen to have an MRI.” Well, no. Despite that unnamed representative’s effort to make a brain tumor sound like a pimple, meningiomas are not anywhere near so universal, and, despite the “benign” designation, can be dangerous, leading to severe disabilities, and, in rare cases, death. “About 2 to 3 percent are malignant,” Dr. Elizabeth Claus, director of medical research at the Yale School of Public Health, a neurosurgeon at Boston’s Brigham and Women’s Hospital, and the principal investigator for the multi-institution Meningioma Consortium, explained in an interview. “Then that is a very serious situation because there’s not much in the way of great treatments. They can metastasize, say to the lungs, and no chemotherapy will work for it.” As the name indicates, a meningioma is a cancer of the meninges, the protective lining that surrounds the brain and spinal cord, often also called the dura. It’s true that meningiomas are one of the most common types of brain tumors, comprising about one-third of all benign brain tumors, but meningiomas are not nearly as common as Crow’s rep would have you believe. As of 2005, approximately 138,000 Americans were known to have been diagnosed of meningioma. © 2012 msnbc.com

Keyword: Miscellaneous
Link ID: 16882 - Posted: 06.07.2012

By Gareth Cook How aware are plants? This is the central question behind a fascinating new book, “What a Plant Knows,” by Daniel Chamovitz, director of the Manna Center for Plant Biosciences at Tel Aviv University. A plant, he argues, can see, smell and feel. It can mount a defense when under siege, and warn its neighbors of trouble on the way. A plant can even be said to have a memory. But does this mean that plants think — or that one can speak of a “neuroscience” of the flower? Chamovitz answered questions from Mind Matters editor Gareth Cook. 1. How did you first get interested in this topic? My interest in the parallels between plant and human senses got their start when I was a young postdoctoral fellow in the laboratory of Xing-Wang Deng at Yale University in the mid 1990s. I was interested in studying a biological process that would be specific to plants, and would not be connected to human biology (probably as a response to the six other “doctors” in my family, all of whom are physicians). So I was drawn to the question of how plants sense light to regulate their development. It had been known for decades that plants use light not only for photosynthesis, but also as a signal that changes the way plants grow. In my research I discovered a unique group of genes necessary for a plant to determine if it’s in the light or in the dark. When we reported our findings, it appeared these genes were unique to the plant kingdom, which fit well with my desire to avoid any thing touching on human biology. But much to my surprise and against all of my plans, I later discovered that this same group of genes is also part of the human DNA. © 2012 Scientific American

Keyword: Evolution
Link ID: 16878 - Posted: 06.06.2012

by Linda Geddes SECOND by second changes in the brain's pH can be visualised for the first time. This ability may provide fresh insights into learning, memory and disease. Oxygen deprivation can alter the brain's pH, and even normal brain signals from acidic neurotransmitters or metabolic by-products such as lactic acid may lead to local changes in pH. Studies in mice have also uncovered pH-sensitive receptors in brain areas involved in emotion and memory - although their function is something of a mystery. "If these receptors are activated by pH change, it's possible that abnormalities in this system could lead to changes in learning, memory and mood," says Vincent Magnotta at the University of Iowa in Iowa City. A common way of studying the brain is with an MRI scanner, which detects differences in the spin of protons in tissues according to water content. Although brain pH can be measured using a form of MRI called MR spectroscopy, it only detects changes that occur over minutes - not fast enough to keep up with the rapid pace of the brain. T1ρ MRI analyses the interaction between spinning protons and other ions in a solution, which changes under different pHs. By tweaking the technique so that multiple measurements could be taken simultaneously, Magnotta and his colleagues have found that T1ρ MRI can detect changes in brain acidity happening over seconds. © Copyright Reed Business Information Ltd.

Keyword: Brain imaging
Link ID: 16845 - Posted: 05.26.2012

By Partha Mitra Frontiers are in short supply. No explorer will again catch that first glimpse of the Pacific Ocean with “wild surmise,” take the first steps on the moon, or arrive first at the Challenger deep – the remotest corners of the earth are now tourist attractions. Even in science, great mysteries have fallen – life itself has gone from being the subject of metaphysical speculation about vital substances to the biophysical understanding of cellular processes. Uncharted territories, both physical and metaphorical, are hard to find. Yet there is one largely unmapped continent, perhaps the most intriguing of them all, because it is the instrument of discovery itself: the human brain. It is the presumptive seat of our thoughts, and feelings, and consciousness. Even the clinical criteria for death feature the brain prominently, so it arbitrates human life as well. One would think, that after a century of intensive research, its outlines would be well known to us: after all, colorful pictures of brain activity have been making regular appearances in the news media for some time. However, if one scratches the surface, our knowledge of how the human brain is put together remains limited: not in some esoteric, complicated manner, but in the straightforward sense that we have simply no means to visualize entire neurons in the brain (and the brain, being a collection of neurons, therefore remains a shut book in important ways). We can’t see them in their full glory, even with all our advanced technology. The problem is that compared to other cells visualized under a microscope, neurons are at the same time very small, and very big. While their soma (cell bodies) are like other cells, neurons can send out branches (axons) that travel very long distances, sometimes several feet, which don’t fit into the sections of tissue that we do histology on. © 2012 Scientific American,

Keyword: Brain imaging
Link ID: 16832 - Posted: 05.23.2012

by Helen Thomson In 1848, 25-year-old railroad supervisor Phineas Gage was using a 3 foot 7 inch iron rod to pack blasting powder into a rock when he triggered an explosion that shot the rod straight through his left cheek and out of the top of his head. His survival and subsequent change in personality made him one of neuroscience's most famous case studies – one of the first to highlight that specific areas of the brain affect particular aspects of behaviour. Now, for the first time, researchers have reconstructed a model of the damage caused to the pathways that connected regions of Gage's brain. The result not only adds dimension to the historical case but also provides insights into conditions such as Alzheimer's disease that result in similar personality changes. Due to the absence of Gage's original brain tissue and lack of a recorded autopsy, estimating the extent of brain damage has been difficult. In 2001, researchers at Harvard University were the last to be given permission by the Warren Anatomical Museum in Cambridge, Massachusetts, to scan Gage's skull. They used computed tomography – essentially a 3D X-ray – but the scans were lost after the researchers left the university. Through some "persistent cajoling" John Van Horn at the University of California, Los Angeles and colleagues recently unearthed the scans. "I just thought it's an absolute shame that this is one of the most valuable pieces of data in the history of neuroscience and it's lying in someone's desk drawer," says Van Horn. © Copyright Reed Business Information Ltd.

Keyword: Emotions; Aggression
Link ID: 16813 - Posted: 05.19.2012