Mason Inman It takes only a tiny magnetic field to see clear through a person's head, a new study shows. A method called ultra-low field magnetic resonance imaging (MRI) has captured its first, blurry shots of a human brain, revealing activity as well as structure. MRI scanners image the human body by detecting how hydrogen atoms respond to magnetic fields. They typically require fields of a few tesla – about 10,000 to 100,000 times stronger than the Earth's magnetic field. The powerful magnets necessary make scanners pricey and also dangerous for people with metal implants. The new device hits a sample with a 30 millitesla magnetic field, about 100 times weaker than is normally used in MRI. The device then uses a 46 microtesla magnetic field – about the same as the Earth's magnetic field – to capture images of the sample. The first target for the device was the head of lead researcher Vadim Zotev of Los Alamos National Laboratory in New Mexico, US (see image, top right). Larger objects"The cost of MRI can be reduced dramatically," Zotev told New Scientist. The new set-up uses several ultra-sensitive sensors called superconducting quantum interference devices (SQUIDs), which have to be kept at very low temperatures. "The most expensive part of our system is the liquid helium cryostat, which costs about $20,000," Zotev adds. © Copyright Reed Business Information Ltd

Keyword: Brain imaging
Link ID: 10970 - Posted: 06.24.2010

Kerri Smith SAN DIEGO Recordings from electrodes in the human brain may offer the first objective way to measure the intensity of pain. Researchers say that they have found a neural signal that correlates with the amount of pain that an individual feels. The signal could be used to refine pain-relief techniques that involve stimulating the brain with electricity, they say. Single cells have previously been identified in the human brain that are active in pain, but their response is binary, signalling either pain or no pain. Now, Morten Kringelbach of the psychiatry department at the University of Oxford, UK, and his colleagues have identified low-frequency brain waves that emanate from two regions buried deep within the brain when a patient is in pain. The more pain that is experienced, the longer the waves last. Kringelbach's team recorded activity from two electrodes positioned in the thalamus and the periaqueductal grey area of 12 awake people who had been undergoing deep-brain stimulation (DBS) for chronic pain. During the recording, the team touched either a painful or pain-free area of the patients' bodies and had patients rate their pain every minute. The duration of the waves — dubbed “pain spindles” — correlated with how intensely the patients felt their pain. “It is an objective measure that correlates with a subjective measure,” says Kringelbach, who presented the findings at the Society for Neuroscience meeting in San Diego, California, last week. © 2007 Nature Publishing Group

Keyword: Pain & Touch
Link ID: 10969 - Posted: 06.24.2010

Roxanne Khamsi Monkeys invest less energy in a task if they see other monkeys receiving better rewards for the same effort, researchers report. They say that their experiment provides new evidence that non-human primates can feel envy. The findings could also help explain why humans have such a keen sense of fairness, according to experts. Previous studies have found that monkeys put less effort into a task when they see cage-mates receiving tastier treats for completing the same task. But scientists have not felt confident in saying why the poorly rewarded animals slack off. Some people have suggested the primates that refuse to repeat the task are simply greedy and therefore only willing to work for a bigger reward. Alternately, it has been proposed that the monkeys stop performing the task because they have received large rewards in the past and feel frustrated by the measly amounts offered in later trials. To understand the monkeys' reluctance to participate in the task, Frans de Waal at the Yerkes National Primate Research Center in Atlanta, Georgia, US, and colleagues decided to try several variations on this experiment. They trained 13 capuchin monkeys (Cebus apella) to retrieve a small rock and place it in the experimenter's hands. In exchange for completing this task, the animals received a reward. © Copyright Reed Business Information Ltd.

Keyword: Emotions; Attention
Link ID: 10968 - Posted: 06.24.2010

By Sandra G. Boodman For six years, Lee J. Nelson searched in vain for the cause of the unrelenting headache centered like a bull's-eye above the bridge of his nose. He consulted nearly 60 doctors, none of whom could find a physical explanation for his pain. He took 100 different medications, but even powerful narcotics brought no more than temporary relief. One doctor who considered his headache a symptom of severe depression suggested electroshock; a specialist at Johns Hopkins proposed last-ditch brain surgery reserved for intractable psychiatric problems. So the day in 2003 that the Northern Virginia consultant found the answer to his baffling and rare medical problem in a 40-year-old article in the National Library of Medicine, he was overcome. "It described patients just like me," Nelson recalled. "I started crying." For Nelson, now 55, and his wife, Neta, an executive at a small pharmaceutical company in Herndon, the discovery of that article in a British medical journal proved to be life-changing. It not only provided a diagnosis for a problem that had stumped dozens of specialists, but also described a surgical treatment for the malady that at times had driven Nelson to talk about suicide and his wife of nearly 30 years to contemplate divorce. © 2007 The Washington Post Company

Keyword: Pain & Touch
Link ID: 10967 - Posted: 06.24.2010

By BENEDICT CAREY Educators and psychologists have long feared that children entering school with behavior problems were doomed to fall behind in the upper grades. But two new studies suggest that those fears are exaggerated. One concluded that kindergartners who are identified as troubled do as well academically as their peers in elementary school. The other found that children with attention deficit disorders suffer primarily from a delay in brain development, not from a deficit or flaw. Experts say the findings of the two studies, being published today in separate journals, could change the way scientists, teachers and parents understand and manage children who are disruptive or emotionally withdrawn in the early years of school. The studies might even prompt a reassessment of the possible causes of disruptive behavior in some children. “I think these may become landmark findings, forcing us to ask whether these acting-out kinds of problems are secondary to the inappropriate maturity expectations that some educators place on young children as soon as they enter classrooms,” said Sharon Landesman Ramey, director of the Georgetown University Center on Health and Education, who was not connected with either study. In one study, an international team of researchers analyzed measures of social and intellectual development from over 16,000 children and found that disruptive or antisocial behaviors in kindergarten did not correlate with academic results at the end of elementary school. Copyright 2007 The New York Times Company

Keyword: ADHD; Aggression
Link ID: 10966 - Posted: 06.24.2010

By CARL ZIMMER If you have ever observed ants marching in and out of a nest, you might have been reminded of a highway buzzing with traffic. To Iain D. Couzin, such a comparison is a cruel insult — to the ants. Americans spend a 3.7 billion hours a year in congested traffic. But you will never see ants stuck in gridlock. Army ants, which Dr. Couzin has spent much time observing in Panama, are particularly good at moving in swarms. If they have to travel over a depression in the ground, they erect bridges so that they can proceed as quickly as possible. “They build the bridges with their living bodies,” said Dr. Couzin, a mathematical biologist at Princeton University and the University of Oxford. “They build them up if they’re required, and they dissolve if they’re not being used.” The reason may be that the ants have had a lot more time to adapt to living in big groups. “We haven’t evolved in the societies we currently live in,” Dr. Couzin said. By studying army ants — as well as birds, fish, locusts and other swarming animals — Dr. Couzin and his colleagues are starting to discover simple rules that allow swarms to work so well. Those rules allow thousands of relatively simple animals to form a collective brain able to make decisions and move like a single organism. Deciphering those rules is a big challenge, however, because the behavior of swarms emerges unpredictably from the actions of thousands or millions of individuals. “No matter how much you look at an individual army ant,” Dr. Couzin said, “you will never get a sense that when you put 1.5 million of them together, they form these bridges and columns. You just cannot know that.” Copyright 2007 The New York Times Company

Keyword: Intelligence
Link ID: 10965 - Posted: 06.24.2010

By PAUL VanDeCARR I grind my teeth at night. Have for years. It’s my secret shame. But now I have the comfort of knowing that at least 8 to 10 percent of the adult population shares my malady. It’s called sleep bruxism, and it refers to the grinding or clenching of teeth. There’s a waking version, too — an unconscious clenching of the teeth, most often owing to stress — but the origins are different and the effects are seldom anywhere near as bad as during sleep, when certain of the body’s protective mechanisms are turned off. Left untreated, it can cause damage to the teeth and surrounding tissue, headaches and jaw pain. Bruxism may be at least as old as the Bible, which describes hell as a state where there is “gnashing of teeth.” I might fairly be accused of hyperbole if I reversed the equation and declared that bruxism can turn sleep into a kind of hell. But you get the idea. It’s a real nuisance. “It’s much like having a large football player standing on the tooth,” says Dr. Noshir Mehta, chairman of general dentistry at Tufts University School of Dental Medicine and director of its Craniofacial Pain Center. Copyright 2007 The New York Times Company

Keyword: Sleep
Link ID: 10964 - Posted: 06.24.2010

Jennifer Viegas Nut-Chomper -- A toothy, nut-chomping large ape from Kenya may represent a new species that was, or was very close to being, the last common ancestor to gorillas, chimpanzees and humans, according to a new study that outlines the recently discovered, 10 million-year-old species. Called Nakalipithecus nakayamai, the ape lived within a critical window of evolutionary time. Lead author Yutaka Kunimatsu explained to Discovery News that molecular studies of living apes indicate gorillas, chimps and humans diverged from each other in Africa during the Late Miocene 11-5 million years ago. "Nakalipithecus is derived from Africa and from an appropriate age," Kunimatsu, a Kyoto University primate researcher, said. Fossil remains of the species, excavated by the researchers in the Samburu Hills of northern Kenya, include a jawbone and 11 telltale teeth. "Based on the dentition, (the ape) was approximately the size of female gorillas to orangutans and it had thick enamel and low, voluminous cusps on its cheek teeth," Kunimatsu explained, "so it is likely that this ape ate a considerable amount of hard objects, possibly nuts or seeds." © 2007 Discovery Communications

Keyword: Evolution
Link ID: 10963 - Posted: 06.24.2010

New York - Mini-strokes lead to a major stroke within one week in 1 out of 20 people and should be treated as a medical emergency, British doctors said on Sunday. They said patients who are immediately treated for small strokes, called transient ischemic attacks (TIAs) had almost no risk of a major stroke soon afterward. But people who did nothing about a TIA had an 11-percent risk of a major stroke within one week, Dr Matthew Giles and Peter Rothwell of the Stroke Prevention Research Unit at the University of Oxford reported. TIAs are smaller versions of major strokes and cause similar symptoms such as dizziness, weakness of an arm or leg or visual disturbances. The symptoms are usually mild and transient, so it's easy for people to ignore these episodes. However, TIAs are a warning sign that a larger stroke may be on the way that can cause paralysis, loss of speech, cognitive confusion or death. For their study, published in the Lancet Neurology, Giles and Rothwell combined results from 18 different groups of patients, a total of more than 10 000 people. Overall, 5 percent of patients had a major stroke within seven days of a TIA, they found. Less than 1 percent of patients treated for a TIA at a specialist neurology clinic went on to have a major stroke within a week, compared with 11 percent of those who ignored the TIA, they found. © 2007 Independent Online.

Keyword: Stroke
Link ID: 10962 - Posted: 06.24.2010

It took hundreds of MRI brain scans to reveal the striking difference in the rate of brain development in kids with ADHD compared to kids without it. As psychiatry researcher Philip Shaw and his colleagues at the National Institute of Mental Health report in the Proceedings of the National Academy of Science, the ADHD kids eventually catch up. "I think it is good news. I think it means that this sort of basic brain biology is intact, all that's different is the timing of it," Shaw says. "If ADHD was a complete deviation away from normal brain development, you'd expect the sequence to be completely disrupted," he says. "It wasn't. So we think this is pretty strong evidence that ADHD is more of a delay in brain development." The research is part of a large study of kids with and without ADHD from age five through young adulthood. This analysis included more than 800 MRI scans of 450 kids, half of whom had ADHD. "One of the strengths of it is that it's an ongoing study so we get a chance to scan children repeatedly as they grow up," Shaw says. The kids in the study group are now at ages 17 to 18. The researchers used advanced software to measure the thickness of cortex, or grey matter, of kids' brains and compare them over time. Previous NIMH research had established how the cortex thickens and thins during childhood and adolescence. © ScienCentral, 2000-2007.

Keyword: ADHD; Brain imaging
Link ID: 10961 - Posted: 06.24.2010

Treating children who have Attention Deficit Hyperactivity Disorder with drugs is not effective in the long-term, research has shown. A study obtained by the BBC's Panorama programme says drugs such as Ritalin and Concerta work no better than therapy after three years of treatment. The findings by an influential US study also suggested long-term use of the drugs could stunt children's growth. It said that the benefits of drugs had previously been exaggerated. The Multimodal Treatment Study of Children with ADHD has been monitoring the treatment of 600 children across the US since the 1990s. In 1999, it concluded that after one year medication worked better than behavioural therapy for ADHD. This finding influenced medical practice on both sides of the Atlantic, and prescription rates in the UK have since tripled. The report's co-author, Professor William Pelham of the University of Buffalo, said: "I think that we exaggerated the beneficial impact of medication in the first study. We had thought that children medicated longer would have better outcomes. That didn't happen to be the case. The children had a substantial decrease in their rate of growth so they weren't growing as much as other kids both in terms of their height and in terms of their weight. And the second was that there were no beneficial effects -none." (C)BBC

Keyword: ADHD
Link ID: 10960 - Posted: 11.12.2007

By LISA SANDERS, M.D. The flashing icon announced that an instant message had arrived. The young woman at her computer at work clicked on it eagerly. It was from her fiancé. Silly boy. She’d only left him an hour ago. “Something’s wrong,” the message read. “What do you mean?” she shot back. “I can’t remember anything,” he wrote. “Like I can’t tell you what we did this weekend.” The young woman’s heart began to race. Her fiancé had been strangely forgetful lately. She thought maybe he was just tired. He’d been having trouble sleeping for a couple months — ever since they’d moved in together. The previous weekend they went to New York to plan their wedding. He had been excited when they set up the trip, but once there he seemed unusually quiet and hesitant. “When is our wedding date?” she quizzed. “Can you tell me that?” “No :(” “Call the doctor. Do it now. Tell them this is an emergency.” Over the next half-hour the 27-year-old man put in three calls to his doctor’s office, but each time, he would forget what they told him by the time he messaged his fiancée. Separated by miles of Interstate and several suburbs, the young woman was frantic. Finally, at her insistence, the man, now terrified, asked a friend to take him to the closest hospital. Copyright 2007 The New York Times Company

Keyword: Learning & Memory; Neuroimmunology
Link ID: 10959 - Posted: 06.24.2010

Bob Adler Rewiring nerve fibres that once served a missing arm to the muscles in an amputee's chest now offers a way to control prosthetic limbs more intuitively and effectively. In clinical trials, an improved interface for this type of prosthetic arm allowed volunteers to use their limbs to perform a variety of tasks up to seven times faster than before, after only minimal training. Previous systems only allowed people to make a few movements, one after the other, but the new one can be used to direct 16 distinct arm, hand and finger movements. The approach, called targeted muscle reinnervation (TMR), was first proposed by Gerald Loeb, a professor of biomedical engineering at the University of Southern California, in Los Angeles, US. He suggested in 1980 that it might be possible to detect and use signals from the motor and sensory nerves that once served a severed limb to control a prosthetic, by reconnecting them to nearby muscle and skin. The idea was taken up by Todd Kuiken, then a medical student and now a pioneering rehabilitation researcher at the Rehabilitation Institute of Chicago (RIC), and Northwestern University, also in Chicago, US. Surviving motor and sensory nerves are first surgically separated from the stump of a patient's arm. Nerves serving chest muscles that once helped support and move the missing limb, but that are no longer useful, are also cut. The motor nerves once used to control the patient's arm are then grafted to those connected to the chest muscles, while the sensory nerves from the missing arm are redirected to tissue under the skin of the chest. © Copyright Reed Business Information Ltd.

Keyword: Robotics
Link ID: 10958 - Posted: 06.24.2010

By Nikhil Swaminathan For the first time, researchers have developed a way to view stem cells in the brains of living animals, including humans—a finding that allows scientists to follow the process neurogenesis (the birth of neurons). The discovery comes just months after scientists confirmed that such cells are generated in adult as well as developing brains. "I was looking for a method that would enable us to study these cells through[out a] life span," says Mirjana Maletic-Savatic, an assistant professor of neurology at Stony Brook University in New York State, who specializes in neurological disorders such as cerebral palsy that premature and low-weight babies are at greater risk of developing. She says the new technique will enable her to track children at risk by monitoring the quantity and behavior of these so-called progenitor cells in their brains. The key ingredient in this process is a substance unique to immature cells that is neither found in mature neurons nor in glia, the brain's nonneuronal support cells. Maletic-Savatic and her colleagues collected samples of each of the three cell types from rat brains (stem cells from embryonic animals, the others from adults) and cultured the varieties separately in the lab. They were able to determine the chemical makeup of each variety—and isolate the compound unique to stem cells—with nuclear magnetic resonance (NMR) spectroscopy. (NMR helps to determine a molecule's structure by measuring the magnetic properties of its subatomic particles.) © 1996-2007 Scientific American, Inc.

Keyword: Neurogenesis; Brain imaging
Link ID: 10957 - Posted: 06.24.2010

By Benjamin Lester A limp handshake might say more about a man than he'd like to admit. According to new research, a firm grip is an indicator of genetic fitness. The findings link grip strength to aggressive behavior and sexual history and might provide insight into the mindsets of bullies. Hand grip strength (HGS) is an inherited trait; about 65% of a person's grip strength is genetically determined, whereas the remaining 35% depends on training and developmental factors such as nutrition. Past studies have connected HGS to various measures of physical condition, including bone density and longevity. "It's a ubiquitous measure of health and vitality," says evolutionary psychologist Gordon Gallup of the University at Albany in New York state. To find out whether HGS also reflects sexual and social behaviors, Gallup and his colleagues recruited 143 undergraduates from the university. The team measured their grip strength and anatomical variables linked to attractiveness--shoulder-to-hip ratio for men and waist-to-hip ratio for women. Each participant also completed a survey about sexual history (including age at first sexual encounter and number of partners) and middle and high school bullying behaviors. © 2007 American Association for the Advancement of Science.

Keyword: Sexual Behavior; Genes & Behavior
Link ID: 10956 - Posted: 06.24.2010

By Jeanne Erdmann SAN DIEGO, CALIFORNIA--Opioid drugs such as morphine are the most powerful painkillers. Unfortunately, in some patients their narcotic effects lead to addiction and the need for ever-escalating doses to quell pain. New research with rats shows that blocking morphine's action on glia--a type of support cell in the nervous system--can reduce these downsides while heightening its potency against pain. Over the past decade, scientists have discovered that glial cells heighten nerve pain, such as sciatica, by exciting the neurons that transmit pain signals. Morphine deadens pain by acting at nerve synapses, but it also activates glial cells, possibly worsening the drug's side effects, such as drowsiness, tolerance, worsening of pain, and addiction. To tease apart morphine's effects on glia and neurons, neuroscientists Linda Watkins and Mark Hutchinson of the University of Colorado, Boulder, took advantage of a drug called AV411 that blocks morphine's effects on glia but not on neurons. It boosted the painkiller: Rats injected with AV411 and morphine showed less response to a painful test than did rats given morphine alone. Watkins and Hutchinson also found that over time, morphine better retained its pain-relieving potency in the rats that also received AV411. © 2007 American Association for the Advancement of Science.

Keyword: Pain & Touch; Glia
Link ID: 10955 - Posted: 06.24.2010

Bruce Bower Scientists have achieved a breakthrough in deciphering the genetics of intelligence. Ironically, they did it by accounting for a key environmental factor. Breast-feeding boosts children's IQs by 6 to 7 points over the IQs of kids who weren't breast-fed, but only if the breast-fed youngsters have inherited a gene variant associated with enhanced chemical processing of mothers' milk, reports a team led by psychologist Avshalom Caspi of King's College London. The new finding supports the controversial hypothesis that fatty acids in breast milk enhance newborn babies' brain development. Moreover, the results demonstrate that intelligence researchers must examine how children's genetic natures interact with the ways in which they're nurtured. "Genes work via specific environmental experiences to shape intellectual development," Caspi says. He and his colleagues present their data in an upcoming Proceedings of the National Academy of Sciences. Two groups of children participated in the study: 1,037 boys and girls born 34 to 35 years ago in New Zealand, who are still living there; and 2,232 boys and girls born 12 to 13 years ago who are growing up in England. ©2007 Science Service

Keyword: Development of the Brain; Intelligence
Link ID: 10954 - Posted: 06.24.2010

By Clare Murphy From the odd capsule of fish oil to major brain surgery, the options for boosting our mental capacity are expanding all the time. Do we need to worry about the advent of a brave new world, where everyone is too clever by half? According to the British Medical Association, we must at least start thinking about the ethics of altering the organ which is so central to our being before there is no turning back. The theory is this: if people are already willing to undergo the risks of plastic surgery in search of the perfect body, who is to suggest they would not do the same to better their brains. Scientists are painting a picture of a time when toddlers pop pills on the way to playgroup while employees are forced to quaff various cocktails to boost their productivity. But sinister as that may sound, the benefits could be immense. A world where everyone is that much brighter might not just make for more enlightened conversation, it could accelerate the quest for a cure for cancer or an end to famine. "We need to balance the benefits against the risks," says Dr Vivienne Nathanson, head of ethics at the BMA. "We're not making any recommendations - but we do want people to look up and engage with this issue before it becomes the norm and it's too late to do anything about it." This is no longer a theoretical debate: to a certain extent it is already happening. Fish oil is already widely available and handed out to children by parents who have been told it could improve school performance by prolonging attention. (C)BBC

Keyword: Development of the Brain; Intelligence
Link ID: 10953 - Posted: 11.09.2007

By Jennifer Couzin When the first powerful, common gene behind obesity was reported this spring, scientists were excited but also left scratching their heads. No one, including the diabetes researchers who uncovered it, had any idea how the gene--FTO--worked. Now, a group has taken the first steps toward deciphering why the FTO protein weighs down the scales. FTO surfaced during a hunt for genes behind type 2 diabetes, but researchers soon recognized that its real role was in obesity (Science, 13 April, p. 185). Although obesity has long been considered partly genetic, genes have been tough to come by. The Science study, which included almost 39,000 people, concluded that having two copies of a certain FTO variant increased weight by about 3 kg--the first clear example of a common obesity gene. Then came the hard part: What does FTO do and how does it do it? To begin answering that, a team from several British institutions considered FTO from different vantage points. At the University of Cambridge, U.K., geneticist Stephen O'Rahilly and his colleagues tried to understand what the FTO protein might do in an animal. In mice, they found high levels of FTO in the brain's hypothalamus, which helps regulate energy balance in the body. Mice that had been denied food had 60% less FTO in one part of their hypothalamus than did those that had eaten normally, hinting that FTO might play a role in appetite. © 2007 American Association for the Advancement of Science.

Keyword: Obesity; Genes & Behavior
Link ID: 10952 - Posted: 06.24.2010

Alison Abbott Tiny trackers help to reveal a bird's thoughts in flight.H-P. LippNeuroscientists have fitted pigeons with recorders that pick up brain activity as the birds fly. The devices confirm that the birds really do use features from a landscape to find their way home. And researchers hope that they will be able to use the caps to unpick how birds use other types of navigational signals at different points in a journey. Scientists are pretty sure from tracking experiments that pigeons use the Sun, Earth’s magnetic field and possibly smells as guiding cues when navigating. In 2004, Hans-Peter Lipp, a behavioural neuroscientist from the University of Zürich in Switzerland, showed that pigeons probably also use visual information. He noted that the birds tend to turn when they hit obvious landmarks like a highway exit1. These tracking experiments collected good information about the birds' location, by fitting modern global positioning system (GPS) loggers to the pigeons’ backs. But no-one has been able to measure directly what information the pigeon are using to navigate — no one has accessed the pigeons' thoughts in flight. "If we see a bird continuing along its path after crossing a bump in the magnetic field that would normally cause it to change direction — is this because it failed to sense the information or had a good reason to ignore it?" asks Lipp. "What’s going on in their minds?" © 2007 Nature Publishing Group

Keyword: Animal Migration
Link ID: 10951 - Posted: 06.24.2010