Biological Psychology Links

By Katherine Harmon If love is said to come from the heart, what about hate? Along with music, religion, irony and a host of other complex concepts, researchers are on the hunt for the neurological underpinnings of hatred. Functional magnetic resonance imaging (fMRI) has begun to reveal how the strong emotion starts to emerge in the brain. Neurobiologist Semir Zeki, of University College London's Laboratory of Neurobiology, led a study last year that scanned the brains of 17 adults as they gazed at images of a person they professed to hate. Across the board, areas in the medial frontal gyrus, right putamen, premotor cortex and medial insula activated. Parts of this so-called "hate circuit," the researchers noted, are also involved in initiating aggressive behavior, but feelings of aggression itself—as well as anger, danger and fear—show different patterns in the brain than hatred does. Certainly loathing can spring from positive feelings, such as romantic love (in the guise of a former partner or perceived rival). But love seems to deactivate areas traditionally associated with judgment, whereas hatred activates areas in the frontal cortex that may be involved in evaluating another person and predicting their behavior. Some commonalities with love, however, are striking, the study authors note. The areas of the putamen and insula that are activated by individual hate are the same as those for romantic love. "This linkage may account for why love and hate are so closely linked to each other in life," they wrote in the October 2008 PLoS ONE. © 1996-2009 Scientific American Inc

The National Institutes of Health Blueprint for Neuroscience Research is launching a $30 million project that will use cutting-edge brain imaging technologies to map the circuitry of the healthy adult human brain. By systematically collecting brain imaging data from hundreds of subjects, the Human Connectome Project (HCP) will yield insight into how brain connections underlie brain function, and will open up new lines of inquiry for human neuroscience. Investigators have been invited to submit detailed proposals to carry out the HCP, which will be funded at up to $6 million per year for five years. The HCP is the first of three Blueprint Grand Challenges, projects that address major questions and issues in neuroscience research. The Blueprint Grand Challenges are intended to promote major leaps in the understanding of brain function, and in approaches for treating brain disorders. The three Blueprint Grand Challenges to be launched in 2009 and 2010 address: * The connectivity of the adult, human brain * Targeted drug development for neurological diseases * The neural basis of chronic pain disorders Scientists have studied the relationship between the structure and function of the human brain since the 1800s. Some parts of the brain serve basic functions such as movement, sensation, emotion, learning and memory. Others are more important for uniquely human functions such as abstract thinking. The connections between brain regions are important for shaping and coordinating these functions, but scientists know little about how different parts of the human brain connect.

by Ewen Callaway, Boston A gadget that could sneak a glimpse inside an astronaut's brain has cleared a significant hurdle, operating successfully aboard an aircraft that simulates the weightlessness of outer space. Eventually, the device could be used to remotely monitor astronauts for signs of brain injury, depression and even mental fatigue that could compromise their ability to make a critical repair of equipment. Gary Strangman, a psychiatrist at Massachusetts General Hospital in Boston, is leading development of the non-invasive scanner, which fires weak pulses of near-infrared light into the brain, then reads back what's reflected. Called near-infrared optical spectroscopy, the approach equates changes in blood flow to brain activity, much like a functional MRI scanner (see Tiny scanner may monitor astronauts' mental health). Aboard a mission, the device could help explain why astronauts sometimes suffer from depression, as well as provide an objective gauge of an astronaut's mental state. The scanner has already garnered $400,000 in NASA funding, but to receive more – and eventually, make it aboard a space mission, it must first pass a series of technological hurdles. In June, researchers tested the device in Florida on an aircraft that achieves periods of weightlessness by flying in steep parabolas. The flight showed the device works outside controlled lab settings, and crucially, that it works in weightlessness. © Copyright Reed Business Information Ltd

By Tina Hesman Saey You may not be riding the latest social wave on Facebook or MySpace, or tweeting your every impulse to fans on Twitter. But your brain is hooked on networking. Vision works because different brain regions link up to connect the dots of light and color into a meaningful picture of the world. Language depends on networks of neural circuitry that make sense of the words you hear or see and that help you generate your side of the conversation. Networks of nerves control the motion of your muscles, allowing you to move smoothly and, when necessary, swiftly. Networks are the “in” thing for brain scientists, as surely as they have been for online social butterflies. Scientists learn about the brain’s networks by asking people to perform all sorts of mental acrobatics — interpreting optical illusions, solving riddles, taking tests of mental or muscular skills. But some neuroscientists think they can learn even more about the brain by asking volunteers to just lie back, close their eyes and let their minds wander. Such unstructured journeys of the mind — be they planning tonight’s dinner, thinking about that meeting at work and what your boss said afterward, debating whether to drive or fly for your next vacation, or recalling that day in your childhood when you first sat in your new tree house listening to birds chirp —turn out to offer clues about one of the most important, mysterious and well-connected networks of all. It’s called the default mode network, and it’s responsible for what the brain does when it is doing nothing in particular. It’s the brain’s core, both physically and mentally, and it’s better connected to the brain’s system of circuits than Kevin Bacon is to movie stars. © Society for Science & the Public 2000 - 2009

By Kelli Whitlock Burton Homing pigeons use landmarks to guide them safely home. But how do the birds track these familiar sites hundreds of meters below as they zip by at 65 kilometers per hour? Scientists are trying to answer that question with a new device that lets them record brain activity as pigeons fly. Exactly how pigeons find their way home is a mystery. While some studies suggest the birds rely on smells, the position of the sun, or Earth's magnetic field to navigate, scientists also know that pigeons use visual landmarks. To see how the pigeons' brains processed these sights, Alexei Vyssotski and colleagues at the University of Zurich in Switzerland developed the Neurologger2, a device that simultaneously tracks the birds' route while also recording brain activity as they fly over familiar sites. Neurologger2 weighs just 2 grams and uses an electroencephalogram to record brain activity. In a study published online this week in Current Biology, the scientists trained 26 pigeons to recognize a loft as their home base. Then, they implanted tiny electrodes on the birds' brains and connected them with Neurologger2. They outfitted the birds with global positioning system monitors and then released them from different points 10 to 30 kilometers away from the loft. Once the birds returned, the researchers removed the devices and compared the record of the birds' brain activity with their positions at the time. Vyssotski found that when the birds flew over landmarks, such as a familiar highway, high-frequency brain waves suddenly got more intense. © 2009 American Association for the Advancement of Science.

Erik Vance Vincent Clark, of the University of New Mexico in Albuquerque, thinks he has something like a crystal ball for drug addicts. By applying traditional psychiatric evaluation and modern fMRI brain imaging to people recovering from drug addiction, he claims to be able to spot who is likely to relapse — months before the relapse actually happens. Clark puts people recovering from cocaine and methamphetamine addiction in an fMRI machine, then asks them to play a game called 'oddball task' which is common in addiction research. Participants hit a button when they see an 'X' on a screen, but not when they see a 'T'. Mixed in are a few distracting 'C's: when these appear, they trigger activity in the posterior cingulate region of the brain in some addicts. Clark later meticulously tracks the volunteers, taking hair and urine samples, to see if they have begun using drugs again. With more than 80% accuracy, Clark says, the test predicted who would relapse (those whose posterior cingulate did not light up) and who would stay straight (those whose posterior cingulate did) over the next six months. Combined with a simple test for a history of mania, it was 89% accurate, he says. Clark presented the results during the annual meeting of the Organization for Human Brain Mapping in San Francisco, California, on 19 June. Nature News talked to him about how he keeps such research going. © 2009 Nature Publishing Group,

Alison Abbott Nearly half of the neuroimaging studies published in prestige journals in 2008 contain unintentionally biased data that could distort their scientific conclusions, according to scientists at the National Institute of Mental Health in Bethesda, Maryland. Experts in the field contacted by Nature have been taken aback by the extent of the methodological errors getting through the supposedly strict peer-review systems of the journals in question. Nikolaus Kriegeskorte, Chris Baker and their colleagues analysed 134 functional magnetic resonance imaging (fMRI) studies published last year in five top journals — Nature, Science, Nature Neuroscience, Neuron and The Journal of Neuroscience. The survey, published in Nature Neuroscience on 26 April (N. Kriegeskorte, W. K. Simmons, P. S. F. Bellgowan and C. I. Baker Nature Neurosci. 12, 535–540; 2009), found that 57 of these papers included at least one so-called 'non-independent selective analysis'; another 20 may also have done so, but did not provide enough information to confirm suspicions. The non-independence of the analysis lies in using the same data to set up the conditions to test a hypothesis, then to confirm it. "We are not saying that the papers draw wrong conclusions, because in some cases the error will not have been critical," says Baker. "But in other cases we don't know, and this creates an ambiguity." © 2009 Nature Publishing Group

By Melinda Wenner Neuroscience has long focused on the brain in terms of components: the visual cortex processes what we see, Broca’s area is the center for language, and so on. As our understanding of the brain has improved, however, it has become clear that a more accurate model depends on how these modules are wired together in circuits. A technique called diffusion tensor imaging (DTI) gives us a tool to probe the nature of those connections. A recent study suggests, for instance, that the more a person seeks out new experiences and relies on social approval, the stronger his or her wiring is among brain areas involved in reward, emotion and decision making. Cognitive neuroscientist Michael Cohen and his colleagues at the University of Bonn in Germany asked 20 adults how often they sought out new experiences and relied on social approval. Then they used DTI to look at the subjects’ white matter, which connects disparate regions of the brain. Cognition and high-level processing happen in gray matter, found mostly in the outer layer of the brain and made up of the main cell bodies of neurons. White matter, on the other hand, is made up of the long, spindly “arms” of neurons, called axons, along which electrical signals travel. (This interior part of the brain looks white because the axons are sheathed in myelin, a white insulating protein that helps signals travel more quickly.) Cohen’s team found that the more the subjects sought new experiences, the stronger their connections were from the hippocampus and amygdala, brain regions involved in decision making and emotion, to the ventral and mesial striatum, areas that process information related to emotion and reward. The scientists also found that the subjects who were most dependent on social approval had stronger than normal connections between the striatum and the prefrontal cortex, a brain area involved in higher-order decision making. © 1996-2009 Scientific American Inc.

By David Dobbs When Helen Mayberg started curing depression by stimulating a previously unknown neural junction box in a brain area called Brodmann’s area 25—discovered through 20 years of dogged research—people asked her where she was going to look next. Her reaction was, “What do you mean, Where am I going to look next? I’m going to look more closely here!” Her closer look is now paying off. In a series of papers last year, Mayberg and several of her colleagues used diffusion tensor imaging (DTI) to reveal the neural circuitry of depression at new levels of precision. This MRI technique illuminates the connective tracts in the brain. For depression, the resulting map may allow a better understanding of what drives the disorder—and much better targeting and patient selection for treatments such as deep-brain stimulation (DBS) that seek to tweak this circuitry. In the early 2000s Mayberg and Wayne C. Drevets, then at Washington University Medical School, separately established that area 25, which appeared to connect several brain regions involved in mood, thought and emotion, is hyperactive in depressed patients. The area’s significance was confirmed when Mayberg and her colleagues at the University of Toronto—neurosurgeon Andres Lazano and psychiatrist Sidney Kennedy—used DBS devices to bring relief to 12 out of 20 intractably depressed patients [see “Turning Off Depression,” by David Dobbs; Scientific American Mind, August/September 2006]. “That confirmed my hypothesis that area 25 is an important crossroads,” Mayberg says. “But exactly what circuits were we affecting?” © 1996-2009 Scientific American Inc.

New research is shining a light on differences in the brains of soldiers with post-traumatic stress disorder when compared with soldiers who return from combat without the condition. The work could some day lead to the use of brain scans to help diagnose PTSD, to tailor treatment or even identify people who might be at risk of developing the problem if they're exposed to violence in a war zone, experts say. 'This is consistent with the hypervigilance symptoms that are associated with PTSD that might make these people be very sensitive to detecting anything that could be relevant for survival.'— Dr. Florin Dolcos Dr. Florin Dolcos, an assistant professor of psychiatry and neuroscience at the University of Alberta, travelled to Italy to present the research Friday at the World Psychiatric Association congress in Florence. The experiments were conducted in North Carolina by a team led by Dr. Rajendra Morey of Duke University. Morey is also director of the neuroimaging lab at Durham Veterans Administration Medical Center. Forty-two U.S. soldiers who had returned from Iraq and Afghanistan took part in the study, including 22 soldiers who had developed post-traumatic stress disorder and 20 who had not. © CBC 2009

By Coco Ballantyne About a year ago, a 42-year-old male gorilla named Fubo living in the Bronx Zoo's Congo Gorilla Forest suffered a seizure for no apparent reason. Concerned about his condition, zoo veterinarians put him on several seizure-controlling medications, which seemed to work, because he didn't have any more occurrences on the meds. But they were worried about the cause: Did Fubo have a brain tumor, a stroke or perhaps some kind of injury? To find out, the Wildlife Conservation Society (WCS), which runs the Bronx Zoo in New York City, contacted the Brain Tumor Foundation (BTF), a nonprofit that provides free brain scans to people living in New York's five boroughs—especially those who cannot afford medical care and want to be screened for possible brain tumors. Furry and weighing 275 pounds (125 kilograms), Fubo was no typical patient, but the BTF was willing to give it a go. On February 25, workers arrived at the zoo in BTF's Bobby Murcer Mobile MRI Unit, a trailer housing a magnetic resonance imaging (MRI) scanner, which uses magnetic fields and radio waves to generate images of structures inside the body. (The MRI-on-wheels is named after the late Bobby Murcer, the New York Yankees All-Star outfielder who went on to become a radio commentator, and who died last year from brain tumor complications.) The whole process of sedating the gorilla, running the scan, and returning him to the Gorilla Forest took about three and a half hours, says veterinarian Paul Calle, director of the WCS's Zoological Health Program. "He was very stable and did well," Calle says, noting that Fubo is now back with his family and doing just fine. © 1996-2009 Scientific American Inc.

By Laura Sanders Harry Potter had it easy: All he had to do to see another wizard’s memories was peer into that wizard’s swirling pensieve. Mind-reading is not so simple for everybody else. But a new study reveals that even those without magical gadgets may one day “see” someone else’s memories. In the study, which appears online March 12 in Current Biology, researchers used patterns of brain activity to accurately predict where someone was standing in a virtual room. Each of four study participants sat down to a computer and toured a large virtual room. The room contained objects that helped volunteers get oriented, including clocks, chairs and pictures. As participants navigated through the virtual space, brain cells preserved the memory of the route taken to the final location (“turn left at the picture of the boat”). Once participants reached their destinations, they stared at blank virtual floor for five seconds. Only then did the researchers measure brain activity with fMRI, to ensure that the measured brain activity stemmed from the memories of getting to the location and not from thoughts associated with any particular object in the virtual room. “Because the floor was identical at each target location, then the only thing we could have been decoding was the spatial location,” explains Eleanor Maguire of University College London, a coauthor of the study. © Society for Science & the Public 2000 - 2009

by Sunita Reed Wouldn’t it be amazing if researchers could scan our brains and see whether we have thrill seeking personality traits? Vanderbilt University psychologist David Zald has come pretty close. He has conducted a study that links thrill seeking behavior with a difference in specific part of the dopamine system in the brain. “Dopamine does a number of different things. Probably most importantly though it’s involved in motivation and reward,” explains Zald. “And it’s the critical chemical in terms of people really wanting to do things.” Specific brain cells, or neurons, make and release dopamine. When dopamine is released its target is specific dopamine receptors on other brain cells in the pleasure centers of the brain. There have been some studies of these receptors in people. But Zald wanted to look at a different structure on the dopamine releasing brain cells themselves, called autoreceptors, which function as brakes to stop the release of dopamine. Zald knew that studies in rodents showed that those with reduced brakes were more likely to explore in novel environments but were also more likely to self-administer cocaine or amphetamines. He also knew there was some limited evidence that individual differences in dopamine functioning was linked to novelty seeking. ©2009 ScienCentral

By Matthias Gamer A young man steals across the hallway, slips through a door and scans the room. He opens a drawer, snatches a wristwatch inside and puts it in his pocket. Then he hurries out the door. Sixty more people perform the same drill, half of them filching a watch and the others, a ring. Psychiatrist F. Andrew Kozel, now at the University of Texas Southwestern Medical Center at Dallas, and his colleagues promised to give a bonus payment to anyone who could conceal the deed from the scientists, who planned to look into their brains for signs of a cover-up. Kozel and his co-workers scanned the volunteers’ brains using functional magnetic resonance imaging, which provides a measure of neural activity in different brain areas. During the scans, the subjects answered questions about the theft such as “Did you steal a watch?” or “Did you steal a ring?” The researchers also asked neutral yes/no queries as well as questions about minor wrongful acts. Each participant could truthfully deny stealing one of the objects but had to lie about the other to conceal the deed. (The volunteers were supposed to answer the unrelated questions truthfully.) Kozel and his team initially identified typical neural activity patterns for true and false statements. Then, in the first use of fMRI to detect deception in individuals, the researchers used the patterns they identified to correctly determine whether each of the subjects had taken a watch or a ring 90 percent of the time. © 1996-2009 Scientific American Inc.

Katharine Sanderson A simple change to magnetic resonance imaging (MRI) machines will provide more uniform coverage at higher powers as well as more room for portly patients. In a market set to be worth more than $5 billion by 2010, the new technology may offer an easier way to get to the high-field machines manufacturers and clinicians see as the next target for hospital imaging. MRI machines use a magnetic field to get hydrogen atoms in the body spinning in a particular way, then knock them off-balance with a radio wave. The small radio-frequency signals given off by the recovering nuclei provide the imaging data. In their new version of the technology, Klaas Pruessmann at the University of Zurich, Switzerland, his student David Brunner and their colleagues removed the radio-frequency coil used to tumble the nuclei from an MRI machine built by Philips Healthcare and replaced it with a system that could do the same job from up to 5 metres away. The university has filed for patents on the technology, which is described on page 994 of this issue. "It's a completely new approach to exciting the signal in MRI," says Andrew Blamire, an MRI expert at the nuclear magnetic resonance centre in Newcastle, UK. "Claustrophobia is a widespread problem in clinical MRI," says Pruessmann. Removing the coil from the machine provides a less constraining cavity. But the potential advantages go further than the patient experience. The easily made change of approach may allow designers of increasingly powerful MRI machines to overcome some of the technical hurdles that trouble them. © 2009 Nature Publishing Group,

Reading a book triggers an active response in a person's brain, replicating the activity described in the story, a study by Washington University researchers in St. Louis, Mo., indicates. A brain-imaging study at Washington University tracked brain activity as participants read sections of a story. What scientists discovered was that parts of the brain associated with certain activities described in the story would light up as the person read those sections. For instance, if a character pulled a light cord in the story, the frontal lobe region, which controls grasping motions, would increase in activity. "There has been good evidence for a while that mental simulation — imagination — can improve performance in sport and other skilled behaviours. This study suggests that readers do mental simulation when they comprehend a story," Jeffrey Zacks, director of the university's dynamic cognition laboratory, told the Guardian newspaper. Zacks is also co-author of the study, soon to be published in the journal Psychological Science. The study's lead author is Nicole Speer. © CBC 2009

By Greg Miller When studying the neurological basis for everything from how we deal with the loss of a loved one to why we crave certain foods, scientists have increasingly turned to functional magnetic resonance imaging (fMRI). As it's most often used, the technique measures blood oxygenation in the brain--and the assumption has always been that areas with more oxygenated blood are areas where neurons are busily firing away. But a new study suggests that's not always true, adding an unexpected wrinkle to this burgeoning field of research. The surprising findings come from experiments with two monkeys. Neuroscientists Yevgeniy Sirotin and Aniruddha Das at Columbia University trained each monkey to monitor a tiny light in an otherwise dark room. When the light turned red, as it did at regular, predictable intervals, a monkey could earn a juice reward by fixing its gaze on the light for a few seconds. Microelectrodes placed in the primary visual cortex, the first way station for visual information in the cerebral cortex, picked up only a steady, quiet chatter of neural activity while the monkeys performed the task. (The small light provided very little visual stimulation, Das says, akin to a single star in an otherwise black sky.) But optical measurements of blood volume and oxygenation told a different story, the researchers report in tomorrow's issue of Nature. These two hemodynamic measures rose and fell in the visual cortex throughout the experiment, repeatedly peaking a few seconds before the monkey had to fix its gaze on the light. The findings indicate that the flow of oxygenated blood to a particular brain region doesn't just increase in response to neural activity but can actually anticipate an expected task, even when nearby neurons are relatively quiet, Das says. That suggests that the association between neural firing and hemodynamics isn't as close as many researchers had assumed. © 2009 American Association for the Advancement of Science

by Jim Giles SOME of the hottest results in the nascent field of social neuroscience, in which emotions and behavioural traits are linked to activity in a particular region of the brain, may be inflated and in some cases entirely spurious. Some experiments correlating brain regions to feelings used a method that inflated the apparent strength of the link So say psychologist Hal Pashler at the University of California, San Diego, and his colleagues, who examined more than 50 studies that relied on functional magnetic resonance imaging (fMRI) brain scans, many published in high-profile journals, and questioned the authors about their methods. Pashler's team say that in most of the studies, which linked brain regions to feelings including social rejection, neuroticism and jealousy, researchers interpreted their data using a method that inflates the strength of the link between a brain region and the emotion or behaviour. The claim is disputed by at least two of the critiqued groups. Both argue that Pashler has misunderstood their results and that their conclusions are backed by other studies. In many of the studies, researchers scan volunteers' brains as they complete a task designed to elicit a particular emotion. They then divide the images from the scans into cubes called voxels, which can each contain millions of neurons, and attempt to correlate the activity of particular voxels with emotional changes reported by the volunteers. © Copyright Reed Business Information Ltd.

It may, in the future, be possible to treat brain diseases with ultrasound THE idea of treating maladies of the mind by blasting the brain with noise sounds, to the layman, like kicking a television set in order to repair it. It is, however, on the cards. The noise in question is ultrasound. This has been used for decades to scan human interiors—particularly wombs containing developing fetuses. The ultrasound is reflected from surfaces within the body (such as the skin of a fetus) in the way that audible sound echoes from a cliff face. William Tyler and his colleagues at Arizona State University, however, want to take things a stage further. They think that ultrasound might be used therapeutically as well. The team knew from experiments done by other groups of researchers that ultrasound can have a physical effect on tissue. Unfortunately, that effect is generally a harmful one. When nerve cells were exposed to it at close range, for example, they heated up and died. Dr Tyler, however, realised that all of the studies he had examined used high-intensity ultrasound. He guessed that lowering the intensity might allow nerve cells to be manipulated without damage. To test this idea, he and his colleagues placed slices of living mouse brain into an artificial version of cerebrospinal fluid, the liquid that cushions the brain. They then beamed different frequencies of low-intensity ultrasound at the slices and monitored the results using dye molecules that give off light in response to the activity of proteins called ion channels. (An ion channel is a molecule that allows the passage of electrically charged atoms of sodium, potassium, calcium and so on through the outer membrane of a cell.) © The Economist Newspaper Limited 2008.

JUDGES in the US are waking up to the potential misuse of brain-scanning technologies. Last month, Judge John Kennedy of the New Jersey Judiciary rallied 50 of his peers to discuss protecting courts from junk neuroscience. In September, an Indian court jailed a murder suspect for life, partly on the basis of a brain scan. Meanwhile Cephos of Tyngsboro, Massachusetts, is one of several US companies that claim to be able to show whether someone is lying using a functional MRI brain scan. Ethical issues aside, many neuroscientists say the scans have not been tested rigorously enough to be admitted in court, and that they could produce false positives. Now judges are coming to the same conclusion. Kennedy's gathering, at the New Jersey Judicial College in Teaneck, agreed that brain scans, if accompanied by the opinion of a medical professional, can reveal if a person is in pain or mentally competent to stand trial, but cannot be used to determine a state of guilt. Scans can reveal if a person is in pain or mentally competent to stand trial, but not guilt No judge in the US has yet accepted fMRI scans in a trial, but Kennedy expects attempts to admit them to increase. "We're taking a peek over the horizon to see what's coming," he says. Such considerations are spurred in part by the "Daubert standard" - a Supreme Court ruling that extended a judge's authority to challenge the credibility of scientific evidence in court. © Copyright Reed Business Information Ltd

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