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ATLANTA – A novel look at the brains of adults with autism has provided new evidence that various brain regions of people with the developmental disorder may not communicate with each other as efficiently as they do in other people. Researchers from the University of Washington's Autism Center will report today at the annual meeting of the Society for Neuroscience on the first study that measures neural activity by using high-resolution electroencephalography (EEG) to examine connections in the cerebral cortex, the part of the brain that deals with higher cognitive processes. Compared to normally developing individuals, the scientists found patterns of abnormal connectivity between brain regions in people with autism. These abnormalities showed both over and under connectivity between neurons in different parts of the cortex, according to Michael Murias, a postdoctoral researcher who headed the study. "Our findings indicate adults with autism show differences in coordinated neural activity," said Murias, "which implies poor internal communication between the parts of the brain." The UW researchers analyzed EEGs from 36 adults, ranging in age from 19 to 38. Half the adults had autism and all had IQs of at least 80. The EEGs, which measure the activity of hundreds of millions of brain cells, were collected with an array of 124 electrodes while the people were seated and relaxed with their eyes closed for two minutes.

A man with an unusually tiny brain manages to live an entirely normal life despite his condition, which was caused by a fluid build-up in his skull. Scans of the 44-year-old man's brain showed that a huge fluid-filled chamber called a ventricle took up most of the room in his skull, leaving little more than a thin sheet of actual brain tissue (see image, right). “It is hard for me [to say] exactly the percentage of reduction of the brain, since we did not use software to measure its volume. But visually, it is more than a 50% to 75% reduction,” says Lionel Feuillet, a neurologist at the Mediterranean University in Marseille, France. Feuillet and his colleagues describe the case of this patient in The Lancet. He is a married father of two children, and works as a civil servant. The man went to a hospital after he had mild weakness in his left leg. When Feuillet's staff took his medical history, they learned that, as an infant, he had had a shunt inserted into his head to drain away hydrocephalus – water on the brain. The shunt was removed when he was 14. But the researchers decided to check the condition of his brain using computed tomography (CT) scanning technology and another type of scan called magnetic resonance imaging (MRI). They were astonished to see "massive enlargement" of the lateral ventricles – usually tiny chambers that hold the cerebrospinal fluid that cushions the brain. © Copyright Reed Business Information Ltd.

The brain of a mammal is one of the most complex things in the universe. But studying brains has become easier thanks to some complicated, hi-tech equipment. In this ScienCentral Web Extra video we take a visit to the Tonegawa Lab at MIT's Picower Institute for Learning and Memory. to see their two-photon microscope and electrophysiology lab. The two-photon microscope has two lasers that intersect in the sample of brain tissue. They excite photons of light which, when amplified, reveal intricate structures. The researchers take snapshots at a range of depths, then combine them to create a layered three dimensional image that reveals features of the spines that protrude from brain cells. Research associate Inbal Israely describes what we're seeing. "So a neuron is like a tree and it has branches, and the branches get finer as you go farther out along the tree. And on the tree you can imagine there are almost like little thorns – they're spines – and the spines are basically the sites of connections between two neurons." © ScienCentral, 2000-2007.

By Sarah Yang, BERKELEY – Neuroscientists at the University of California, Berkeley, have for the first time measured the electrical activity of nerve cells and correlated it to changes in blood flow in response to transcranial magnetic stimulation (TMS), a noninvasive method to stimulate neurons in the brain. Their findings, reported in the Sept. 28 issue of the journal Science, could substantially improve the effectiveness of brain stimulation as a therapeutic and research tool. TMS works by generating magnetic pulses via a wire coil placed on top of the scalp. The pulses pass harmlessly through the skull and induce short, weak electrical currents that alter neural activity. Yet the relative scarcity of data describing the basic effects of TMS, and the uncertainty in how the method achieves its effects, prompted the researchers to conduct their own study. "There are potentially limitless applications in both the treatment of clinical disorders as well as in fundamental research in neuroscience," said Elena Allen, a graduate student at UC Berkeley's Helen Wills Neuroscience Institute (HWNI) and co-lead author of the study. "For example, TMS could be used to help determine what parts of the brain are used in object recognition or speech comprehension. However, to develop effective applications of TMS, it is first necessary to determine basic information about how the technique works." Copyright UC Regents

Roxanne Khamsi The reason why even professional basketball and soccer players sometimes miss an easy shot may be partly explained by spontaneous fluctuations of electrical activity within the brain, a study suggests. An experiment conducted by researchers at Washington University, in Missouri, US, found that fluctuations in brain activity caused volunteers to subconsciously exert slightly less physical force when pressing a button on cue. Crucially, this activity is independent of any external stimulus and does not appear related to attention or anticipation. The scientists involved say it is the first direct evidence that internal instabilities – so-called "spontaneous brain activity" – may play an important role in the variability of human behaviour. From the mid-1990s onwards, brain-scanning techniques have revealed variable brain activity that appears unrelated to external stimuli and occurs even when a person is asleep or anaesthetized. But just how such fluctuations in neuronal firings may influence physical behaviour has proven different to untangle. To explore the issue, Michael Fox at Washington University and colleagues designed an experiment that involved monitoring volunteers' brains using functional magnetic resonance imaging (fMRI) as they performed a simple finger-tapping task. © Copyright Reed Business Information Ltd.

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

Michael Marshall Talk about getting under someone's skin. Impressionists seem to use visual images to "become" the people they are imitating, according to a brain-scanning study that started as a public demonstration and is now being expanded. Sophie Scott, of the Institute of Cognitive Neuroscience at University College London, asked impressionist Duncan Wisbey to lie in an fMRI brain scanner and repeat phrases in a variety of different voices – including the actor Cary Grant and the British TV chef Anthony Worrall Thompson. Other accents Wisbey impersonated included "baleful Cockney" and "tired Australian". As a control, he repeated the same phrases in his own voice. When Wisbey was imitating others, there was higher activity in his parietal lobe, sensory motor strip and supplementary motor areas of the brain. These areas are respectively involved in visual imagery, body representation and vocalisation. "For basic speech production, his results are normal," says Scott. "The extra activities [when doing impressions] are in very plausible areas. These areas are known to be active in mental imagery tasks." © Copyright Reed Business Information Ltd

Kerri Smith A computer model has been developed that can predict what word you are thinking of. The model may help to resolve questions about how the brain processes words and language, and might even lead to techniques for decoding people’s thoughts. Researchers led by Tom Mitchell of Carnegie Mellon University in Pittsburgh, Pennsylvania, 'trained' a computer model to recognize the patterns of brain activity associated with 60 images, each of which represented a different noun, such as 'celery' or 'aeroplane'. The team started with the assumption that the brain processes words in terms of how they relate to movement and sensory information. Words such as 'hammer', for example, are known to cause movement-related areas of the brain to light up; on the other hand, the word 'castle' triggers activity in regions that process spatial information. Mitchell and his colleagues also knew that different nouns are associated more often with some verbs than with others – the verb 'eat', for example, is more likely to be found in conjunction with 'celery' than with 'aeroplane'. © 2008 Nature Publishing Group

Alison Abbott The director of a top laboratory in Germany has charged that two of his former research students took data from his laboratory without his permission and published scientifically incorrect interpretations of them against his advice. One of the two editors-in-chief of Human Brain Mapping, Peter Fox of the University of Texas Health Science Center in San Antonio, told Nature that the paper was correctly refereed, but declined to add details. Logothetis is furious about the publication of data, which he believes will mislead the field, and about the fact that the authors of the paper allege that he tried to stop them publishing the data for personal reasons. The affair began in the spring, when Amir Shmuel, who worked in Logothetis's laboratories from 2002 to 2007 and is now at the Montreal Neurological Institute of McGill University in Canada, asked Logothetis for permission to use data generated there. Although he agreed at first, Logothetis withdrew his permission when he realized that the data — from functional magnetic resonance imaging studies on monkey brains — were being used to support a theory about spontaneous brain activity. The data had been collected when monkeys were looking at a grey but flickering LED screen. “The protocol was just inappropriate for analysis of spontaneous brain activity,” says Logothetis. © 2008 Nature Publishing Group –

Ewen Callaway With jam-packed schedules and a video feed to Earth, astronauts enjoy precious little privacy as it is. Soon, doctors might peek into an astronaut's last bastion of solitude, thanks to a portable brain scanner that could one day go into orbit. Mission control could use the device 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. "If you had a magic cap to say, 'Are you good to go?' that might be valuable," says Jonathan Clark of the National Space Biomedical Research Institute (NSBRI) in Houston, Texas, US, which funds the work. "Think of it like a breathalyser for the brain." But the scanner, currently under development at Massachusetts General Hospital in Boston, US, must prove its worth and safety before NASA even considers sending a brain scanner into orbit, Clark tells New Scientist. Unlike the hulking, tunnel-like MRI machines that peer into the brain with super-strong magnets, the space brain scanner resembles a large remote control tethered to a Velcro headband by long, thin wires. Yet the technology – called near-infrared optical spectroscopy – works something like functional MRI, which equates changes in blood flow to brain activity.

Colin Barras A microscope small enough to be mounted to the head of a freely moving mouse makes it possible to watch brain cell activity and whole animal behaviour simultaneously in mice. The device offers researchers a new way to study of human diseases using transgenic mice. Since researchers created the first transgenic mice in the 1980s, the mouse has become the lab animal of choice for medical research. There are now mouse "models" for a wide range of human genetic disorders, from Parkinson's to asthma. But correlating the activity inside cells with the behaviour of an animal as a whole is still a challenge, says Mark Schnitzer at Stanford University. Cell spotter "A lot of work has been done using brain slices, or anaesthetised animals – even using animals that are awake but restrained," he says. But so far it has been impossible to image cellular-level activity in a freely moving mouse. Schnitzer's team has now made it possible. They designed a tiny microscope weighing just 1.1 grams that can be worn by a mouse without significantly impairing its movement. The device has already been used to study the circulation of blood through the one-cell-wide capillaries in the brain of active mice. © Copyright Reed Business Information Ltd.

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 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

A small microscope that can be mounted on an animal's head should offer a front-row view of how its brain processes visual and other stimuli on the move. A laser inside the device scans the activity of neurons through a tiny hole in the skull, made prior to the experiment under anaesthetic. When the microscope was attached to freely moving rats looking at screens, it produced images of brain cells that had been labelled with a fluorescent dye. Compared with previous methods – which require restraining animals and inserting electrodes – this technique is much less invasive, revealing brain activity in animals that are moving and interacting with their environment in a more natural way. It was developed at the Max Planck Institute for Biological Cybernetics in T�bingen, Germany. Journal reference: Proceedings of the National Academy of Sciences, DOI: 10.1073/pnas.0903680106 © Copyright Reed Business Information Ltd.

by Ewen Callaway A chemical produced during sex and linked to addiction has been visualised in a scanner as it washes across rats' brains. The feat means that functional magnetic resonance imaging (fMRI), a workhorse of neuroscience, can now be used to observe the flow of brain chemicals, not just oxygen-rich blood. By pinpointing increases in blood oxygenation in the brain in response to different events – a sign that specific groups of neurons are active – fMRI is responsible for some of the hottest findings about the brain. Now Alan Jasanoff at the Massachusetts Institute of Technology and colleagues have extended its power. His team repeatedly mutated a magnetic, iron-containing enzyme that "lights up" in fMRI readings. With each mutation, the researchers tested its tendency to bind to dopamine, a learning and reward chemical in the brain involved in sex and addictive behaviours. Mutations that increased this tendency were combined, resulting in a molecule that was both magnetic and strongly attracted to dopamine. The team injected the molecule into the brains of rats, in a region laden with dopamine-producing cells. When given a chemical that triggers dopamine release, that area "lit up" under fMRI. Because the molecule must be injected into the brain, this kind of chemical-based fMRI won't be applied to humans anytime soon, says Jasanoff, but it could be used to probe addiction and disease using animals. © Copyright Reed Business Information Ltd

by Ewen Callaway You spend more time window shopping than you may realise. Whether someone intends to buy a product or not can be predicted from their brain activity – even when they are not consciously pondering their choices. The ability to predict from brain scans alone what a person intends to buy, while leaving the potential buyer none the wiser, could bring much-needed rigour to efforts to meld marketing and neuroscience, says Brian Knutson, a neuroscientist at Stanford University in California who was not involved in the research. NeuromarketingMovie Camera, as this field is known, has been employed by drug firms, Hollywood studios and even the Campbell Soup Company to sell their wares, despite little published proof of its effectiveness. Rather than soup, John-Dylan Haynes at the Bernstein Center for Computational Neuroscience in Berlin, Germany, attempted to predict which cars people might unconsciously favour. To do so, he and colleague Anita Tusche used functional MRI to scan the brains of two groups of male volunteers, aged 24 to 32, while they were presented with images of a variety of cars. One group was asked to rate their impressions of the vehicles, while the second performed a distracting visual task while cars were presented in the background. Each volunteer was then shown three cars and asked which they would prefer to buy. © Copyright Reed Business Information Ltd.

UCLA researchers are the first to report altered brain function in people who respond favorably to placebo treatment for major depression. In addition, the findings show these changes are different than those found in people who respond to antidepressant medication. The study, appearing in the January edition of the peer-reviewed American Journal of Psychiatry, used quantitative electroencephalography (QEEG) imaging to examine brain electrical activity in patients treated for depression with placebo, and others treated with antidepressant medication. The researchers examined QEEG cordance, a measure associated with blood flow in the brain. Patients who responded to placebo — an inert substance, such as a sugar pill — showed increased activity in the brain’s prefrontal cortex, while those who responded to medication showed suppressed activity in that area.

From The Economist print edition Genetics may yet threaten privacy, kill autonomy, make society homogeneous and gut the concept of human nature. But neuroscience could do all of these things first IN THE genetically engineered world portrayed in “Gattaca”, a movie made in 1997, the hero and heroine attend a concert in which a pianist performs a concerto that can be played only by a person with six fingers on each hand. This is a society in which genetic perfectionists have had their way. The concert-goers have been altered before birth to be free of such ailments as baldness, obesity and diabetes, and to be tall, good-looking and intelligent. In that room, improbable as it may seem, only Ethan Hawke has lived a life free of genetic enhancement; he alone has had to take his chances with the genetic lottery of natural conception. Compare this scene to one in which the effects of neurotechnology (technology that makes it possible to manipulate the brain) are pervasive. The old man on the left of the aisle is being saved from Alzheimer's disease by an implant that bathes his brain cells in a healthy broth of chemicals. The little girl in the circle, vows her doctor, has a cortex that will one day win her a Nobel prize in physics—if she keeps up the correct regime of “cogniceuticals”, of course. As a condition of their employment, the security guards posted at the entrance had to undergo brain scans to demonstrate that they were free of propensities to uncontrollable rage. The musicians on stage are on drugs that speed their reflexes, heighten their hearing and assuage their performance anxiety. Not that different from “Gattaca”, is it? Copyright © The Economist Newspaper Limited 2002. All rights reserved.

UPTON, NY — The idea that obese people eat too much because they find food more palatable than lean people do has gained support from a new brain-imaging study at the U.S. Department of Energy’s Brookhaven National Laboratory. The study reveals that the parts of the brain responsible for sensation in the mouth, lips, and tongue are more active in obese people than in normal-weight control subjects. “This enhanced activity in brain regions involved with sensory processing of food could make obese people more sensitive to the rewarding properties of food, and could be one of the reasons they overeat,” said Brookhaven physician Gene-Jack Wang, lead author of the study. Wang acknowledges that obesity is a complex disease with many contributing factors, including genetics, abnormal eating behavior, lack of exercise, and cultural influences, as well as cerebral mechanisms, which are not yet fully understood. In a recent study, he and his team found that obese people have fewer brain receptors for dopamine, a neurotransmitter that helps produce feelings of satisfaction and pleasure, implying that obese people may eat to stimulate their underserved reward circuits, just as addicts do by taking drugs.

The Dynamic Brain Atlas could be a giant leap forward for neuroscience BY THOMAS K. GROSE When a doctor looks at a patient's brain scan, some problems are immediately clear. Tumors, for instance, aren't easily hidden. Other subtle abnormalities are harder to detect, however. So for years, doctors have relied on brain atlases — compendiums of scans of normal brains in book form — to make comparisons and spot differences. But book atlases are far from infallible. "The traditional atlas is an extrapolation of the general population," explains Jo Hajnal, a physicist at the MRC Clinical Services Centre at London's Imperial College. "They contain only whatever the preparer thought was useful," he adds. Now computer technology is giving physicians a much more powerful diagnostic tool: brain atlas images customized to each patient. Hajnal is part of a team of researchers at Imperial College and King's College London that has devised a Dynamic Brain Atlas, which runs from a networked laptop. The current prototype can access hundreds of images stored in databases around the world and create a composite image that closely approximates each patient's brain. Copyright © 2002 Time Inc. All rights reserved.

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