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By GINA KOLATA He learned there was a new brain scan to diagnose the disease and nervously agreed to get her one, secretly hoping it would lay his fears to rest. In June, his wife became what her doctor says is the first private patient in Arizona to have the test. “The scan was floridly positive,” said her doctor, Adam S. Fleisher, director of brain imaging at the Banner Alzheimer’s Institute in Phoenix. The Jimenezes have struggled ever since to deal with this devastating news. They are confronting a problem of the new era of Alzheimer’s research: The ability to detect the disease has leapt far ahead of treatments. There are none that can stop or even significantly slow the inexorable progression to dementia and death. Families like the Jimenezes, with no good options, can only ask: Should they live their lives differently, get their affairs in order, join a clinical trial of an experimental drug? “I was hoping the scan would be negative,” Mr. Jimenez said. “When I found out it was positive, my heart sank.” The new brain scan technology, which went on the market in June, is spreading fast. There are already more than 300 hospitals and imaging centers, located in most major metropolitan areas, that are ready to perform the scans, according to Eli Lilly, which sells the tracer used to mark plaque for the scan. © 2012 The New York Times Company

Keyword: Alzheimers
Link ID: 17501 - Posted: 11.17.2012

Sandrine Ceurstemont, editor, New Scientist TV Improving your mathematical skills could now be as easy as playing a Kinect video game in a hat. In preliminary tests of the system, developed by Roi Cohen Kadosh and colleagues from the University of Oxford, participants were better with numbers after just two days of training. In this video, our technology features editor Sally Adee gives the game a go while testing a new cap that wirelessly delivers electrical brain stimulation. The device is controlled by a computer, which controls things like the duration of the zapping. Although it can stimulate various brain regions, in this case it sends current to the right parietal cortex. "The parietal region is involved in numerical understanding," says Cohen Kadosh. "So amplifying the function of this region should lead to a better performance." So far, the team has shown that brain stimulation while doing computer-based mathematics exercises helped maintain better mathematical skills in adults even six months later. But Cohen Kadosh thinks that the Kinect game is much more promising as a training tool because it's fun and engaging. By requiring a player to represent a fraction by moving their body to position it on a line, the gameplay also integrates three key components linked to mathematical ability: numerical understanding, the ability to perceive the spatial relationship of visual representations and embodiment. Cohen Kadosh believes this enhances the training. © Copyright Reed Business Information Ltd

Keyword: Intelligence; Learning & Memory
Link ID: 17500 - Posted: 11.17.2012

By Laura Sanders The insidious spread of an abnormal protein may be behind Parkinson’s disease, a study in mice suggests. A harmful version of the protein crawls through the brains of healthy mice, killing brain cells and damaging the animals’ balance and coordination, researchers report in the Nov. 16 Science. If a similar process happens in humans, the results could eventually point to ways to stop Parkinson’s destruction in the brain. “I really think that this model will increase our ability to come up with Parkinson’s disease therapies,” says study coauthor Virginia Lee of the University of Pennsylvania Perelman School of Medicine in Philadelphia. The new study targets a hallmark of Parkinson’s disease — clumps of a protein called alpha-synuclein. The clumps, called Lewy bodies, pile up inside nerve cells in the brain and cause trouble, particularly in cells that make dopamine, a chemical messenger that helps control movement. Death of these dopamine-producing cells leads to the characteristic tremors and muscle rigidity seen in people with Parkinson’s. Lee and her team injected alpha-synuclein into the brains of healthy mice. After 30 days, the protein had spread to connected brain regions, suggesting that rouge alpha-synuclein moves from cell to cell, the scientists found. Months later, the spreading was even more extensive. © Society for Science & the Public 2000 - 2012

Keyword: Parkinsons
Link ID: 17499 - Posted: 11.17.2012

Daniel Cressey Rappers making up rhymes on the fly while in a brain scanner have provided an insight into the creative process. Freestyle rapping — in which a performer improvises a song by stringing together unrehearsed lyrics — is a highly prized skill in hip hop. But instead of watching a performance in a club, Siyuan Liu and Allen Braun, neuroscientists at the US National Institute on Deafness and Other Communication Disorders in Bethesda, Maryland, and their colleagues had 12 rappers freestyle in a functional magnetic resonance imaging (fMRI) machine. The artists also recited a set of memorized lyrics chosen by the researchers. By comparing the brain scans from rappers taken during freestyling to those taken during the rote recitation, they were able to see which areas of the brain are used during improvisation. The study is published today in Scientific Reports1. The results parallel previous imaging studies in which Braun and Charles Limb, a doctor and musician at Johns Hopkins University in Baltimore, Maryland, looked at fMRI scans from jazz musicians2. Both sets of artists showed lower activity in part of their frontal lobes called the dorsolateral prefrontal cortex during improvisation, and increased activity in another area, called the medial prefrontal cortex. The areas that were found to be ‘deactivated’ are associated with regulating other brain functions. © 2012 Nature Publishing Group

Keyword: Brain imaging; Laterality
Link ID: 17498 - Posted: 11.17.2012

by Douglas Heaven All the better to hear you with, my dear. A chance discovery has revealed that some insects have evolved mammal-like ears, with an analogous three-part structure that includes a fluid-filled vessel similar to the mammalian cochlea. Fernando Montealegre-Z at the University of Lincoln, UK, and colleagues were studying the vibration of the tympanal membrane – a taut membrane that works like an eardrum – in the foreleg of Copiphora gorgonensis, a species of katydid from the South American rainforest, when they noticed tiny vibrations in the rigid cuticle behind the membrane. When they dissected the leg behind that membrane, they unexpectedly burst a vessel filled with high-pressure fluid. The team analysed the fluid to confirm that it was not part of the insect's circulatory system and concluded instead that it played a cochlea-like role in sound detection. In most insects, sound vibrations transmit directly to neuronal sensors which sit behind the tympanal membrane. Mammals have evolved tiny bones called ossicles that transfer vibrations from the eardrum to the fluid-filled cochlea. The analogous structure in the katydid is a vibrating plate, exposed to the air on one side and fluid on the other. Smallest ear In mammals, the cochlea analyses a sound's frequency – how high or low it is – and the new structure found by the team appears to do the same job. Spanning only 600 micrometres, it is the smallest known ear of its kind in nature. © Copyright Reed Business Information Ltd.

Keyword: Hearing; Evolution
Link ID: 17497 - Posted: 11.17.2012

Mo Costandi Albert Einstein is considered to be one of the most intelligent people that ever lived, so researchers are naturally curious about what made his brain tick. Photographs taken shortly after his death, but never before analysed in detail, have now revealed that Einstein’s brain had several unusual features, providing tantalizing clues about the neural basis of his extraordinary mental abilities1. While doing Einstein's autopsy, the pathologist Thomas Harvey removed the physicist's brain and preserved it in formalin. He then took dozens of black and white photographs of it before it was cut up into 240 blocks. He then took tissue samples from each block, mounted them onto microscope slides and distributed the slides to some of the world’s best neuropathologists. The autopsy revealed that Einstein’s brain was smaller than average and subsequent analyses showed all the changes that normally occur with ageing. Nothing more was analysed, however. Harvey stored the brain fragments in a formalin-filled jar in a cider box kept under a beer cooler in his office. Decades later, several researchers asked Harvey for some samples, and noticed some unusual features when analysing them. A study done in 1985 showed that two parts of his brain contained an unusually large number of non-neuronal cells called glia for every neuron2. And one published more than a decade later showed that the parietal lobe lacks a furrow and a structure called the operculum3. The missing furrow may have enhanced the connections in this region, which is thought to be involved in visuo-spatial functions and mathematical skills such as arithmetic. © 2012 Nature Publishing Group

Keyword: Brain imaging; Intelligence
Link ID: 17496 - Posted: 11.17.2012

By Melissa Healy, Los Angeles Times If retired Army Gen. David H. Petraeus had gotten an occasional dose of supplemental oxytocin, a brain chemical known to promote trust and bonding, he might still be director of the Central Intelligence Agency, new research suggests. A study published Tuesday in the Journal of Neuroscience has uncovered a surprising new property of oxytocin, finding that when men in monogamous relationships got a sniff of the stuff, they subsequently put a little extra space between themselves and an attractive woman they'd just met. Oxytocin didn't have the same effect on single heterosexual men, who comfortably parked themselves between 21 and 24 inches from the comely female stranger. The men who declared themselves in "stable, monogamous" relationships and got a dose of the hormone chose to stand, on average, about 6 1/2 inches farther away. When researchers conducted the experiment with a placebo, they found no differences in the distance that attached and unattached men maintained from a woman they had just met. Even when an attractive woman was portrayed only in a photograph, the monogamous men who received oxytocin put a bit more distance between themselves and her likeness. But when the new acquaintance was a man, administration of oxytocin did not prompt attached men to stand farther away than single men, the researchers reported. Los Angeles Times, Copyright 2012

Keyword: Hormones & Behavior; Sexual Behavior
Link ID: 17495 - Posted: 11.17.2012

In 2009, Susannah Cahalan was a healthy 24-year-old reporter for the New York Post, when she began to experience numbness, paranoia, sensitivity to light and erratic behavior. Grasping for an answer, Cahalan asked herself as it was happening, "Am I just bad at my job — is that why? Is the pressure of it getting to me? Is it a new relationship?" But Cahalan only got worse — she began to experience seizures, hallucinations, increasingly psychotic behavior and even catatonia. Her symptoms frightened family members and baffled a series of doctors. After a monthlong hospital stay and $1 million worth of blood tests and brain scans that proved inconclusive, Cahalan was seen by Dr. Souhel Najjar, who asked her to draw a clock on a piece of paper. "I drew a circle, and I drew the numbers 1 to 12 all on the right-hand side of the clock, so the left-hand side was blank, completely blank," she tells Fresh Air's Dave Davies, "which showed him that I was experiencing left-side spatial neglect and, likely, the right side of my brain responsible for the left field of vision was inflamed." As Najjar put it to her parents, "her brain was on fire." This discovery led to her eventual diagnosis and treatment for anti-NMDA receptor encephalitis, a rare autoimmune disease that can attack the brain. Cahalan says that doctors think the illness may account for cases of "demonic possession" throughout history. Cahalan's new memoir is called Brain on Fire: My Month of Madness. ©2012 NPR

Keyword: Schizophrenia; Neuroimmunology
Link ID: 17494 - Posted: 11.17.2012

by Douglas Heaven What is nine plus six, plus eight? You may not realise it, but you already know the answer. It seems that we unconsciously perform more complicated feats of reasoning than previously thought – including reading and basic mathematics. The discovery raises questions about the necessity of consciousness for abstract thought, and supports the idea that maths might not be an exclusively human trait. Previous studies have shown that we can subliminally process single words and numbers. To identify whether we can unconsciously perform more complicated processing, Ran Hassin at the Hebrew University of Jerusalem, Israel, and his colleagues used a technique called continuous flash suppression. The technique works by presenting a volunteer's left eye with a stimulus – a mathematical sum, say – for a short period of time, while bombarding the right eye with rapidly changing colourful shapes. The volunteer's awareness is dominated by what the right eye sees, so they remain unconscious of what is presented to the left eye. In the team's first experiment, a three-part calculation was flashed to the left eye. This was immediately followed by one number being presented to both eyes, which the volunteer had to say as fast as possible. When the number was the same as the answer to the sum, people were quicker to announce it, suggesting that they had subconsciously worked out the answer, and primed themselves with that number. © Copyright Reed Business Information Ltd.

Keyword: Attention; Consciousness
Link ID: 17493 - Posted: 11.14.2012

Tom Pugh A gene with links to late-onset dementia is also suspected of boosting people's brains in their youth, according to a study. People who inherit one copy of the gene variant, known as APOE e4, have up to four times the normal risk of developing Alzheimer's disease in later life. Neuroscientists tested the cognitive skills of those with the gene variant, which is found in around a quarter of the population, against those without it. They also looked at the brain structure and brain activities of both groups during the tasks. The study, led by the University of Sussex, found that young people with the same variant performed better in attention tests, including episodic memory of words and spotting number sequences. Experts suggested that while the e4 variant might help boost the brain in early life, it could also increase the possibility of "burnout" in old age. Lead researcher Professor Jennifer Rusted said: "Earlier studies suggested that those with the e4 variant outperform those without it in tasks such as memory, speed of processing, mental arithmetic and verbal fluency. "But it is also well-established that this gene is a risk factor for Alzheimer's disease. © independent.co.uk

Keyword: Alzheimers; Genes & Behavior
Link ID: 17492 - Posted: 11.14.2012

By Hal Arkowitz and Scott O. Lilienfeld When Mick Jagger first sang “What a drag it is getting old,” he was 23 years old. Now at 69, he is still a veritable Jumpin' Jack Flash on stage. Jagger seems to have found the secret to staying physically fit in his advancing years, but getting old can be a drag on the psyche. Many older adults fear memory loss and worry they are headed down the road to dementia, such as Alzheimer's disease. Every time they forget their keys, leave a door unlocked or fail to remember a name, they are reminded of this nagging concern. In most cases, however, such annoying incidents are part of normal age-related memory loss, not a sign of impending dementia. Although lots of older adults think such a decline is inevitable, there is good news for many of them. Researchers have developed an array of helpful methods and activities that exercise our minds and bodies that can help keep the older mind in relatively good condition. In this column, we examine the most promising ways to shore up memory in the normal aging brain. Memory is not a single entity. The term encompasses several types of remembering, not all of which decline with age. For instance, older people still retain their vocabulary, along with general knowledge about the world (semantic memory). They can also perform certain routine tasks, such as making an omelet or typing on a computer (procedural memory), about as well as they could when they were younger. People do become worse, however, at recalling recent events in their lives (episodic memory) or where they first learned a piece of information (source memory), managing the temporary storage of short-term information (working memory), and remembering to do things in the future (prospective memory). © 2012 Scientific American

Keyword: Learning & Memory; Alzheimers
Link ID: 17491 - Posted: 11.14.2012

One cannot travel far in spiritual circles without meeting people who are fascinated by the “near-death experience” (NDE). The phenomenon has been described as follows: Frequently recurring features include feelings of peace and joy; a sense of being out of one’s body and watching events going on around one’s body and, occasionally, at some distant physical location; a cessation of pain; seeing a dark tunnel or void; seeing an unusually bright light, sometimes experienced as a “Being of Light” that radiates love and may speak or otherwise communicate with the person; encountering other beings, often deceased persons whom the experiencer recognizes; experiencing a revival of memories or even a full life review, sometimes accompanied by feelings of judgment; seeing some “other realm,” often of great beauty; sensing a barrier or border beyond which the person cannot go; and returning to the body, often reluctantly. Such accounts have led many people to believe that consciousness must be independent of the brain. Unfortunately, these experiences vary across cultures, and no single feature is common to them all. One would think that if a nonphysical domain were truly being explored, some universal characteristics would stand out. Hindus and Christians would not substantially disagree—and one certainly wouldn’t expect the after-death state of South Indians to diverge from that of North Indians, as has been reported.⁠ It should also trouble NDE enthusiasts that only 10−20 percent of people who approach clinical death recall having any experience at all.⁠ Copyright 2012 Sam Harris

Keyword: Attention; Consciousness
Link ID: 17490 - Posted: 11.14.2012

by Andy Coghlan Men with partners increase the space they feel comfortable with between themselves and an attractive woman if exposed to the bonding hormone oxytocin. René Hurlemann at the University of Bonn in Germany and colleagues gave men either a sniff of oxytocin or a placebo before asking them to choose the ideal distance for an interaction with a woman. The distance that they felt was comfortable significantly increased after sniffing oxytocin, but only for men in relationships. The team conclude that oxytocin discourages partnered but not single men from getting close to a female stranger. Journal reference: Journal of Neuroscience, DOI: 10.1523/jneurosci.2755-12.2012 © Copyright Reed Business Information Ltd.

Keyword: Hormones & Behavior; Sexual Behavior
Link ID: 17489 - Posted: 11.14.2012

Women with migraines did not appear to experience a decline in cognitive ability over time compared to those who didn’t have them, according to a nine-year follow up study funded by the National Institutes of Health. The study also showed that women with migraine had a higher likelihood of having brain changes that appeared as bright spots on magnetic resonance imaging (MRI), a type of imaging commonly used to evaluate tissues of the body. "The fact that there is no evidence of cognitive loss among these women is good news," said Linda Porter, Ph.D., pain health science policy advisor in the Office of the Director at the National Institute of Neurological Disorders and Stroke (NINDS), which provided funding for the study. "We’ve known for a while that women with migraine tend to have these brain changes as seen on MRI. This nine-year study is the first of its kind to provide long-term follow-up looking for associated risk." "An important message from the study is that there seems no need for more aggressive treatment or prevention of attacks," said Mark C. Kruit, M.D., Ph.D., one of the principal investigators, and a neuroradiologist from Leiden University Medical Center, the Netherlands, which led the study. Dr. Kruit and associates evaluated MRIs for changes in the white matter, brainstem, and cerebellum that appeared on the scans as bright spots known as hyperintensities. Previous studies have shown an association between such hyperintensities and risk factors for atherosclerotic disease, increased risk of stroke and cognitive decline.

Keyword: Pain & Touch
Link ID: 17488 - Posted: 11.14.2012

By Fergus Walsh Medical correspondent A Canadian man who was believed to have been in a vegetative state for more than a decade, has been able to tell scientists that he is not in any pain. It's the first time an uncommunicative, severely brain-injured patient has been able to give answers clinically relevant to their care. Scott Routley, 39, was asked questions while having his brain activity scanned in an fMRI machine. His doctor says the discovery means medical textbooks will need rewriting. Vegetative patients emerge from a coma into a condition where they have periods awake, with their eyes open, but have no perception of themselves or the outside world. Mr Routley suffered a severe brain injury in a car accident 12 years ago. None of his physical assessments since then have shown any sign of awareness, or ability to communicate. But the British neuroscientist Prof Adrian Owen - who led the team at the Brain and Mind Institute, University of Western Ontario - said Mr Routley was clearly not vegetative. BBC © 2012

Keyword: Attention; Consciousness
Link ID: 17487 - Posted: 11.13.2012

by Elizabeth Norton Stop that noise! Many creatures, such as human babies, chimpanzees, and chicks, react negatively to dissonance—harsh, unstable, grating sounds. Since the days of the ancient Greeks, scientists have wondered why the ear prefers harmony. Now, scientists suggest that the reason may go deeper than an aversion to the way clashing notes abrade auditory nerves; instead, it may lie in the very structure of the ear and brain, which are designed to respond to the elegantly spaced structure of a harmonious sound. "Over the past century, researchers have tried to relate the perception of dissonance to the underlying acoustics of the signals," says psychoacoustician Marion Cousineau of the University of Montreal in Canada. In a musical chord, for example, several notes combine to produce a sound wave containing all of the individual frequencies of each tone. Specifically, the wave contains the base, or "fundamental," frequency for each note plus multiples of that frequency known as harmonics. Upon reaching the ear, these frequencies are carried by the auditory nerve to the brain. If the chord is harmonic, or "consonant," the notes are spaced neatly enough so that the individual fibers of the auditory nerve carry specific frequencies to the brain. By perceiving both the parts and the harmonious whole, the brain responds to what scientists call harmonicity. In a dissonant chord, however, some of the notes and their harmonics are so close together that two notes will stimulate the same set of auditory nerve fibers. This clash gives the sound a rough quality known as beating, in which the almost-equal frequencies interfere to create a warbling sound. Most researchers thought that phenomenon accounted for the unpleasantness of a dissonance. © 2010 American Association for the Advancement of Science

Keyword: Hearing
Link ID: 17486 - Posted: 11.13.2012

By SINDYA N. BHANOO Fairywrens teach their chicks a password, a unique note, to differentiate them from imposters. “We call this an incubation call,” said Mark Hauber, an animal behaviorist at Hunter College at the City University of New York and an author of the study, which appears in the journal Current Biology. “The more times the mother calls, the better the mimicry of the chicks.” The teaching begins a few days before the birds hatch. And while “the cuckoo chick is very adaptable and tries out many begging calls until it sounds similar to the fairywren,” Dr. Hauber said, it also has a shorter incubation period. So it hatches several days before fairywren chicks, leaving it little time to practice and perfect the passwordlike call of the fairywren mother. Generally, when a cuckoo hatches it throws out the other eggs in the nest. When a mother does not hear her unique call from her babies, she abandons the nest. Male fairywrens help their mates care for their young, so the mother teaches her mate and any other helpers the password through the performance of a special song. “In the future we’d like to do some brain imaging on the embryos using noninvasive functional M.R.I.’s,” Dr. Hauber said. “We want to see how these embryos are listening, practicing and learning these relevant vocalizations.” © 2012 The New York Times Company

Keyword: Sexual Behavior; Learning & Memory
Link ID: 17485 - Posted: 11.13.2012

by Greg Miller Seeing someone yawn or hearing someone laugh makes you likely to follow suit. The same goes for scratching an itch. Now, for the first time, researchers have investigated the neural basis of contagious itch, identifying several brain regions whose activity predicts how susceptible people are to feeling itchy when they see someone else scratch. Researchers in the United Kingdom showed volunteers video clips of people scratching an arm or a spot on their chest. Sure enough, subjects reported feeling more itchy, and most scratched themselves at least once during the experiment. When a subset of the volunteers watched the videos inside an functional magnetic resonance imaging scanner, the scans revealed activity in several of the same brain regions known to fire up in response to an itch-inducing histamine injection. Activity in three of these areas correlated with subjects' self-reported itchiness, the team reports online today in the Proceedings of the National Academy of Sciences. Personality tests suggest that the trait that best predicts susceptibility to contagious itch is neuroticism, not empathy, as some researchers have suggested. © 2010 American Association for the Advancement of Science

Keyword: Pain & Touch; Emotions
Link ID: 17484 - Posted: 11.13.2012

By NICHOLAS BAKALAR High blood pressure may cause harmful brain changes in people as young as 40, a study suggests. In the report, published online Nov. 2 in Lancet Neurology, researchers measured blood pressure in 579 men and women whose average age was 39, then examined their brains with magnetic resonance imaging. After adjusting for smoking, hypertension treatment and total cranial volume, they found that higher systolic blood pressure — the most common form of hypertension — was associated with decreases in gray matter volume and significant injury to white matter. Moreover, there was a dose-response relationship: The higher the blood pressure, the greater the visible changes. These changes also occur in people over 55 with high blood pressure and are associated with decreased cognitive performance. Essentially, these young people with high blood pressure had brains that were older than their chronological age. The authors acknowledge that their sample was mostly healthy, white volunteers, and that the study represents a snapshot, not a long-term picture. The senior author, Dr. Charles DeCarli, a neurologist at the University of California, Davis, urged caution. “Most people at this age have no symptoms at all, even if they have high blood pressure,” he said. “Get your blood pressure measured when you’re young, and treated if necessary.” Copyright 2012 The New York Times Company

Keyword: Alzheimers
Link ID: 17483 - Posted: 11.13.2012

By James Gallagher Health and science reporter, BBC News Adding "calm down" genes to hyperactive brain cells has completely cured rats of epilepsy for the first time, say UK researchers. They believe their approach could help people who cannot control their seizures with drugs. The study, published in the journal Science Translation Medicine, used a virus to insert the new genes into a small number of neurons. About 50 million people have epilepsy worldwide. However, drugs do not work for up to 30% of them. The alternatives include surgery to remove the part of the brain that triggers a fit or to use electrical stimulation. The brain is alive with electrical communication with individual neurons primed to fire off new messages. However, if a group of neurons become too excited they can throw the whole system into chaos leading to an epileptic seizure. Researchers at University College London have developed two ways of manipulating the behaviour of individual cells inside the brain in order to prevent those seizures. Both use viruses injected into the brain to add tiny sections of DNA to the genetic code of just a few thousand neurons. One method boosts the brain cells' natural levels of inhibition in order to calm them down. This treatment is a form of gene therapy, a field which is often criticised for failing to deliver on decades of promise. BBC © 2012

Keyword: Epilepsy; Genes & Behavior
Link ID: 17482 - Posted: 11.13.2012