By Scicurious This past weekend, I read an interesting piece in the New Yorker. It’s another one of the current rash of pieces that are warning us (rightly!) to beware of neuro-hype. It references another recent piece in the New York Times, which referenced those fighting back against things like “How Creativity Works” (correct answer: it’s very complicated and we don’t know), and the ever-present fMRI studies hyped in the news (I’ve been guilty of a few of those, though I try very hard to be skeptical). Both pieces referenced the excellent Neuroskeptic and Neurocritic (though sadly, the NYT didn’t give them the links they definitely deserve). And both pieces warned that neuroscience is more, and better than, the gee-whiz of “This is your brain on poker“. I particularly liked the New Yorker piece, for making clear the incredible complexity of the human brain. The brain, though, rarely works that way. Most of the interesting things that the brain does involve many different pieces of tissue working together. Saying that emotion is in the amygdala, or that decision-making is the prefrontal cortex, is at best a shorthand, and a misleading one at that. Different emotions, for example, rely on different combinations of neural substrates. The act of comprehending a sentence likely involves Broca’s area (the language-related spot on the left side of the brain that they may have told you about in college), but it also draws on the parts of the brain in the temporal lobe that analyze acoustic signals, and part of sensorimotor cortex and the basal ganglia become active as well. (In congenitally blind people, some of the visual cortex also plays a role.) It’s not one spot, it’s many, some of which may be less active but still vital, and what really matters is how vast networks of neural tissue work together. © 2012 Scientific American

Keyword: Brain imaging
Link ID: 17568 - Posted: 12.04.2012

Posted by Gary Marcus In the early nineteen-nineties, David Poeppel, then a graduate student at M.I.T. (and a classmate of mine)—discovered an astonishing thing. He was studying the neurophysiological basis of speech perception, and a new technique had just come into vogue, called positron emission tomography (PET). About half a dozen PET studies of speech perception had been published, all in top journals, and David tried to synthesize them, essentially by comparing which parts of the brain were said to be active during the processing of speech in each of the studies. What he found, shockingly, was that there was virtually no agreement. Every new study had published with great fanfare, but collectively they were so inconsistent they seemed to add up to nothing. It was like six different witnesses describing a crime in six different ways. This was terrible news for neuroscience—if six studies led to six different answers, why should anybody believe anything that neuroscientists had to say? Much hand-wringing followed. Was it because PET, which involves injecting a radioactive tracer into the brain, was unreliable? Were the studies themselves somehow sloppy? Nobody seemed to know. And then, surprisingly, the field prospered. Brain imaging became more, not less, popular. The technique of PET was replaced with the more flexible technique of functional magnetic resonance imaging (fMRI), which allowed scientists to study people’s brains without the use of the risky radioactive tracers, and to conduct longer studies that collected more data and yielded more reliable results. Experimental methods gradually become more careful. As fMRI machines become more widely available, and methods became more standardized and refined, researchers finally started to find a degree of consensus between labs. © 2012 Condé Nast.

Keyword: Brain imaging
Link ID: 17567 - Posted: 12.04.2012

Roger Dobson Love, according to romantics, can have a dramatic effect on the senses: striking lovers blind, deaf or rendering them tongue-tied. But the simple answer to the question of whether any relationship is "the one" seems to be that your ideal man or woman gets up your nose. New research suggests a sense of smell is vital for a good long-term relationship. In the new study, reported in the journal Biological Psychology, researchers looked for the first time at the effect of being born without a sense on smell on men and women's relationships. The research involved analysing data on men and women aged 18 to 46 with no sense of smell and comparing it with information gleaned from a healthy control group. The results showed that men and women who were unable to smell had higher levels of social insecurity, although this manifested itself in different ways. In men, but not in women, it led to fewer relationships. The men with a faulty sense of smell averaged two partners compared with 10 for healthy men. One theory is that the lack of a sense of smell may make men less adventurous. They may have more problems assessing and communicating with other people. They may also be concerned about how they are perceived by others, and worry about their own body odour. © independent.co.uk

Keyword: Chemical Senses (Smell & Taste); Sexual Behavior
Link ID: 17566 - Posted: 12.03.2012

By KEN BELSON The growing evidence of a link between head trauma and long-term, degenerative brain disease was amplified in an extensive study of athletes, military veterans and others who absorbed repeated hits to the head, according to new findings published in the scientific journal Brain. The study, which included brain samples taken posthumously from 85 people who had histories of repeated mild traumatic brain injury, added to the mounting body of research revealing the possible consequences of routine hits to the head in sports like football and hockey. The possibility that such mild head trauma could result in long-term cognitive impairment has come to vex sports officials, team doctors, athletes and parents in recent years. Of the group of 85 people, 80 percent (68 men) — nearly all of whom played sports — showed evidence of chronic traumatic encephalopathy, or C.T.E., a degenerative and incurable disease whose symptoms can include memory loss, depression and dementia. Among the group found to have C.T.E., 50 were football players, including 33 who played in the N.F.L. Among them were stars like Dave Duerson, Cookie Gilchrist and John Mackey. Many of the players were linemen and running backs, positions that tend to have more contact with opponents. Six high school football players, nine college football players, seven pro boxers and four N.H.L. players, including Derek Boogaard, the former hockey enforcer who died from an accidental overdose of alcohol and painkillers, also showed signs of C.T.E. The study also included 21 veterans, most of whom were also athletes, who showed signs of C.T.E. © 2012 The New York Times Company

Keyword: Brain Injury/Concussion
Link ID: 17565 - Posted: 12.03.2012

By Brian Mossop Ten years into serving a life sentence for the rape of Jennifer Thompson, Ronald Cotton stepped out of prison a free man. It took that long for DNA evidence to exonerate Cotton, refuting a weak case built mostly on eyewitness accounts. According to Simon's new book In Doubt, despite advances in DNA forensic technologies, eyewitness testimony remains the most common way to nab criminals in the Anglo-American justice system. The problem, however, is that our mind often subconsciously twists the evidence to coincide with our biases, and we end up incarcerating innocent people. Simon, a professor of law and psychology at the University of Southern California, says that the false conviction rate, based on exoneration data from capital murder cases, is estimated to be near 5 percent, although that figure represents only a fraction of those wrongly imprisoned. Eyewitness testimony boils down to how well the witness remembers the event. Studies have shown that a victim of a crime may remember a specific piece of information from the horrid event, such as the attacker's jacket or a strange smell, but fail to recall other details. Investigators are left with a weak profile of the perpetrator. In Cotton's case, the victim initially chose two men from the lineup, and only after repeated questioning from investigators could Thompson say Cotton was her assailant. © 2012 Scientific American

Keyword: Learning & Memory
Link ID: 17564 - Posted: 12.03.2012

By Michelle Warwicker BBC Nature The youngest members of zebra finch broods "explore more" than older siblings in adult life, say scientists. Researchers investigated how the birds' behaviour was affected by the way their parents cared for them as hatchlings. The team studied broods where females lay and incubate a clutch of eggs over a period of days, resulting in a size hierarchy within the clutch. They found the youngest birds were more likely to explore their environment as adults in search of food. The study, published in Animal Behaviour, tested over 100 captive zebra finches' exploratory behaviour to see whether hatching order, and consequently parental investment, affected their behaviour in adulthood. Late hatched birds are smaller than their older siblings, and it is the larger hatchlings that "get the lion's share" when parents bring in food "because they can reach up higher and beg better," explained research team member Dr Ian Hartley from Lancaster University. Hatching eggs over a span of time, rather than all at once, is known as "hatching asynchrony" and occurs when eggs are incubated as soon as they are laid. For zebra finch, this means that birds born up to four days apart can share the same nest and must compete for food. BBC © 2012

Keyword: Development of the Brain; Emotions
Link ID: 17563 - Posted: 12.03.2012

Barry Gordon, professor of neurology and cognitive science at the Johns Hopkins University School of Medicine, replies: Forgive your mind this minor annoyance because it has worked to save your life—or more accurately, the lives of your ancestors. Most likely you have not needed to worry whether the rustling in the underbrush is a rabbit or a leopard, or had to identify the best escape route on a walk by the lake, or to wonder whether the funny pattern in the grass is a snake or dead branch. Yet these were life-or-death decisions to our ancestors. Optimal moment-to-moment readiness requires a brain that is working constantly, an effort that takes a great deal of energy. (To put this in context, the modern human brain is only 2 percent of our body weight, but it uses 20 percent of our resting energy.) Such an energy-hungry brain, one that is constantly seeking clues, connections and mechanisms, is only possible with a mammalian metabolism tuned to a constant high rate. Constant thinking is what propelled us from being a favorite food on the savanna—and a species that nearly went extinct—to becoming the most accomplished life-form on this planet. Even in the modern world, our mind always churns to find hazards and opportunities in the data we derive from our surroundings, somewhat like a search engine server. Our brain goes one step further, however, by also thinking proactively, a task that takes even more mental processing. So even though most of us no longer worry about leopards in the grass, we do encounter new dangers and opportunities: employment, interest rates, “70 percent off” sales and swindlers offering $20 million for just a small investment on our part. Our primate heritage brought us another benefit: the ability to navigate a social system. As social animals, we must keep track of who's on top and who's not and who might help us and who might hurt us. To learn and understand this information, our mind is constantly calculating “what if?” scenarios. What do I have to do to advance in the workplace or social or financial hierarchy? What is the danger here? The opportunity? © 2012 Scientific American

Keyword: Attention
Link ID: 17562 - Posted: 12.03.2012

By Lindsey Tanner, The Associated Press CHICAGO -- The now familiar term "Asperger's disorder" is being dropped. And abnormally bad and frequent temper tantrums will be given a scientific-sounding diagnosis called DMDD. But "dyslexia" and other learning disorders remain. The revisions come in the first major rewrite in nearly 20 years of the diagnostic guide used by the nation's psychiatrists. Changes were approved Saturday. Full details of all the revisions will come next May when the American Psychiatric Association's new diagnostic manual is published, but the impact will be huge, affecting millions of children and adults worldwide. The manual also is important for the insurance industry in deciding what treatment to pay for, and it helps schools decide how to allot special education. This diagnostic guide "defines what constellations of symptoms" doctors recognize as mental disorders, said Dr. Mark Olfson, a Columbia University psychiatry professor. More important, he said, it "shapes who will receive what treatment. Even seemingly subtle changes to the criteria can have substantial effects on patterns of care." Olfson was not involved in the revision process. The changes were approved Saturday in suburban Washington, D.C., by the psychiatric association's board of trustees. The aim is not to expand the number of people diagnosed with mental illness, but to ensure that affected children and adults are more accurately diagnosed so they can get the most appropriate treatment, said Dr. David Kupfer. He chaired the task force in charge of revising the manual and is a psychiatry professor at the University of Pittsburgh. © 2012 NBCNews.com

Keyword: Autism
Link ID: 17561 - Posted: 12.03.2012

By Kate Shaw Early one morning I caught sight of Morpheus, silhouetted against a pink African dawn. Her long, sloping neck was stretched out as she loped away from me, disappearing over a hill. I followed her to a nearby plain and was met with the unmistakable sound of a group of hyenas squabbling over a carcass. Morpheus entered the fray, first lunging at a smaller male on her right. A moment later, she looked up briefly, her nose and mouth covered in blood, then turned and snapped at a hyena feeding nearby. I’m intimately acquainted with Morpheus and these other hyenas because they have been studied for more than twenty years by various members of the lab where I did my Ph.D. research; I’ve staked these hyenas out at dens for hours on end and followed them as they raced across open plains. From watching these animals, we’ve learned about hyenas’ social system, their physiology, and the conservation challenges they face. But to me, it’s the aggression that is the most fascinating thing about hyenas. It’s rule-based and constrained by specific social norms, but at the same time, it’s incredibly primal and ruthless. Studying aggression has helped us understand what makes hyenas tick, offering us a glimpse into the evolutionary pressures that have made them one of the most unusual and misunderstood species in the animal kingdom. For more than 1000 years, people believed that hyenas were hermaphrodites, since female hyenas have long, fully-erectile pseudopenises that mimic male genitalia. Seeing a hyena play the role of mom while sporting what looks like a penis would bewilder even an astute naturalist. Not only do female hyenas look like males, they are also the more aggressive and socially dominant sex, exhibiting aggression more than three times more often than male hyenas do. © 2012 Scientific American

Keyword: Aggression; Hormones & Behavior
Link ID: 17560 - Posted: 12.01.2012

Children who are obese may be more vulnerable to food advertising, a brain scanning study suggests. Food and beverage companies market to children to establish brand recognition, brand preference and loyalty. Previous studies found preschoolers said foods tasted better wrapped in branded packaging than plain packaging and kids were more likely to try to influence their parents' purchases when exposed to ads. Researchers in the U.S. suspected that children who are obese would show greater activation to food logos in the "drive" regions of the brain compared with healthy weight children. Amanda Bruce of the psychology department at the University of Missouri-Kansas City and her colleagues looked at 10 healthy children and 10 obese children aged 10 to 14 using questionnaires measuring self-control and functional magnetic resonance imaging of brain activity. Other corporate logos and blurred images were also tested. Obese children showed more activation in some reward regions of the brain than the healthy weight children when shown food logos. But that wasn't the case for the control regions of the brain. "When shown food logos, obese children showed significantly less brain activation than the healthy weight children in regions association with cognitive control," the study's authors concluded in Friday's issue of The Journal of Pediatrics. "This provides initial neuroimaging evidence that obese children may be more vulnerable to the effects of food advertising." © CBC 2012

Keyword: Obesity; Attention
Link ID: 17559 - Posted: 12.01.2012

by Emily Underwood On the reality television show Extreme Makeover: Home Edition, the lucky recipient gets a first look at his newly renovated home. For a split second, his face contorts with—shock? Joy? During intense emotional experiences, there's a fleeting moment when expressions of pleasure and pain are hard to distinguish. In fact, others read intense emotion more effectively by looking at a person's body language than by watching his facial expressions, a new study suggests. Most studies of facial cues rely on a set of stylized, recognizable expressions—perhaps made by actors in photographs. The actors make expressions meant to be obvious enough to translate across cultures: anger, disgust, fear, joy, sadness, and surprise. But these stylized images don't necessarily reflect the expressions that people make in the real world, says Hillel Aviezer, a neuropsychologist at who is now at The Hebrew University of Jerusalem and lead author of the new study, published online today in Science. Moreover, when emotions get particularly extreme, people undergoing fleeting peaks of intense pain, joy, grief, or anger look surprisingly similar, Aviezer says. From the face, at least, "when you compare extreme pain to extreme pleasure, you really can't tell them apart," he says. And yet most people are rarely confused about whether someone is experiencing grief or joy. To figure out what tips us off, Aviezer and his colleagues showed photos of professional tennis players to 45 Princeton University students, randomly divided into three groups of 15. Each tennis player had just won or lost an important match, and the participants rated the players' contorted facial expressions from negative to positive on a scale from 1 to 9, with 5 marking the neutral midway point. One group of participants looked at head-to-toe photos of the players, the second group looked at only the players' bodies, and the third group looked at only their heads. Only the final group had trouble making the correct identification, suggesting that facial expressions alone didn't tell them whether the players were joyous or in despair. © 2010 American Association for the Advancement of Science

Keyword: Emotions; Evolution
Link ID: 17558 - Posted: 12.01.2012

By Laura Sanders A new computer simulation of the brain can count, remember and gamble. And the system, called Spaun, performs these tasks in a way that’s eerily similar to how people do. Short for Semantic Pointer Architecture Unified Network, Spaun is a crude approximation of the human brain. But scientists hope that the program and efforts like it could be a proving ground to test ideas about the brain. Several groups of scientists have been racing to construct a realistic model of the human brain, or at least parts of it. What distinguishes Spaun from other attempts is that the model actually does something, says computational neuroscientist Christian Machens of the Champalimaud Centre for the Unknown in Lisbon, Portugal. At the end of an intense computational session, Spaun spits out instructions for a behavior, such as how to reproduce a number it’s been shown. “And of course, that’s why the brain is interesting,” Machens says. “That’s what makes it different from a plant.” Like a digital Frankenstein’s monster, Spaun was cobbled together from bits and pieces of knowledge gleaned from years of basic brain research. The behavior of 2.5 million nerve cells in parts of the brain important for vision, memory, reasoning and other tasks forms the basis of the new system, says Chris Eliasmith of the University of Waterloo in Canada, coauthor of the study, which appears in the Nov. 30 Science. © Society for Science & the Public 2000 - 2012

Keyword: Robotics
Link ID: 17557 - Posted: 12.01.2012

By LISA SANDERS, M.D. On Thursday, we challenged Well readers to puzzle their way through the case of a 25-year-old elephant trainer who developed “the worst headache of his life.” The case was made more confusing by the fact that he had been head-butted by a zebra several years earlier. Turns out the zebra was a bit of a red herring – for the doctors at the time, and for many of you. The correct diagnosis is… Herpes zoster, commonly known as shingles The internist assigned to the case, Dr. Bilal Ahmed, was able to make the diagnosis because when he examined the patient the next day, he saw the characteristic zoster rash above the patient’s right eye that had developed overnight. Nearly 200 people wrote in with their thoughts on what Dr. Ahmed might have seen to reveal the diagnosis when he looked at the patient. The first person to guess the correct diagnosis was Lotty Fulkerson of Massachusetts, a licensed practical nurse who has seen a lot of zoster. It was the combination of the patient’s terrible pain and the fact that the doctor saw something that told him the diagnosis that made her think it was probably shingles. Only three other readers guessed correctly. Herpes zoster, also known as shingles, is caused by the re-emergence of the herpes virus that is the source of the childhood illness chickenpox. The term “shingles” comes from the Latin word “cingulum,” which means belt or girdle; the rash of herpes zoster often appears in a band or belt-like pattern. When the original chickenpox infection resolves, the virus doesn’t die but instead takes refuge in branches of the nerves just outside the spinal cord, where it will reside for decades. In up to a third of patients who have had chickenpox, it re-emerges, causing pain and a rash and sometimes more. Why these survivor viruses re-emerge is unclear, but it may be linked to a weakened immune system. Copyright 2012 The New York Times Company

Keyword: Pain & Touch
Link ID: 17556 - Posted: 12.01.2012

Mice with a condition that serves as a laboratory model for Down syndrome perform better on memory and learning tasks as adults if they were treated before birth with neuroprotective peptides, according to researchers at the National Institutes of Health. Down syndrome results when an individual receives an extra copy of chromosome 21. According to the Centers for Disease Control and Prevention, Down syndrome occurs in 1 of every 691 births. Features of Down syndrome include delays in mental and physical development and poor muscle tone. These features may vary greatly, ranging from mild to severe. The researchers studied growth factors that are important at certain key stages of brain development in the womb. Named for the first three amino acids making up their chemical sequence, NAP and SAL, are small peptides (small protein sub units) of two proteins. These two proteins enhance the ability of brain cells to receive and transmit signals, and enable them to survive. (NAP is an abbreviation for NAPVSIPQ and SALfor SALLRSIPA.) The mice in the study had an extra copy of mouse chromosome 16, which has mouse counterparts to 55 percent of the genes on human chromosome 21.The researchers treated pregnant mice with NAP and SAL for five days, then tested the mouse offspring at 8 to 12 months of age, comparing them to mice treated with a saline solution (placebo). Mice with the extra chromosomal material that were treated with NAP and SAL in the womb learned as well as mice that did not have the extra chromosome, and significantly faster than mice with the extra chromosome that were treated with saline solution.

Keyword: Development of the Brain; Genes & Behavior
Link ID: 17555 - Posted: 12.01.2012

by Jessica Hamzelou A single session of nerve stimulation has improved the movement of people with spinal cord injuries. Mimicking the passage of nerve signals by stimulating a muscle as well as the brain has boosted recovery and helped people to regain better control of their movements. Voluntary movement requires a signal from the brain, which is passed down the spinal cord and then to neurons in muscles. Damage to the spinal cord can interrupt this pathway, resulting in paralysis. To improve the control of movement in people with these injuries, Monica Perez and Karen Bunday at the University of Pittsburgh in Pennsylvania used electrical and magnetic stimulation to strengthen the connection between two nerves involved in voluntary movement of the index finger. The pair used transcranial magnetic stimulation (TMS), a non-invasive technique in which a magnetic field alters brain activity, to target the corticospinal tract. This bundle of nerves connects movement-associated parts of the brain with the spinal cord. "The corticospinal tract plays a major role in the recovery of motor function in spinal cord injury," says Perez. Just 1 to 2 milliseconds after stimulating the brain, they used an electrode to stimulate a nerve that innervates an index-finger muscle – mimicking normal brain-to-muscle nerve signalling. © Copyright Reed Business Information Ltd.

Keyword: Regeneration
Link ID: 17554 - Posted: 12.01.2012

By Melissa Hogenboom BBC News Researchers say a baby's chance of being obese in childhood can be predicted at birth using a simple formula. The formula combines several known factors to estimate the risk of obesity. The authors of the study, published in PLos One, hope it will be used to identify babies at risk. Childhood obesity can lead to many health problems, including Type 2 diabetes and heart disease. Researchers from Imperial College London looked at 4,032 Finnish children born in 1986 and at data from two further studies of 1,503 Italian children and 1,032 US children. They found that looking at a few simple measurements, such as a child's birthweight and whether the mother smoked, was enough to predict obesity. Previously it had been thought that genetic factors would give bigger clues to later weight problems, but only about one in 10 cases of obesity is the result of a rare gene mutation that affects appetite. Obesity in children is rising, with the NHS estimating that 17% of boys and 15% of girls in England are now obese. BBC © 2012

Keyword: Obesity; Development of the Brain
Link ID: 17553 - Posted: 11.29.2012

By ANAHAD O'CONNOR Weight loss surgery, which in recent years has been seen as an increasingly attractive option for treating Type 2 diabetes, may not be as effective against the disease as it was initially thought to be, according to a new report. The study found that many obese Type 2 diabetics who undergo gastric bypass surgery do not experience a remission of their disease, and of those that do, about a third redevelop diabetes within five years of their operation. The findings contrast with the growing perception that surgery is essentially a cure for Type II diabetes. Earlier this year, two widely publicized studies reported that surgery worked better than drugs, diet and exercise in causing a remission of Type 2 diabetes in overweight people whose blood sugar was out of control, leading some experts to call for greater use of surgery in treating the disease. But the studies were small and relatively short, lasting under two years. The latest study, published in the journal Obesity Surgery, tracked thousands of diabetics who had gastric bypass surgery for more than a decade. It found that many people whose diabetes at first went away were likely to have it return. While weight regain is a common problem among those who undergo bariatric surgery, regaining lost weight did not appear to be the cause of diabetes relapse. Instead, the study found that people whose diabetes was most severe or in its later stages when they had surgery were more likely to have a relapse, regardless of whether they regained weight. Copyright 2012 The New York Times Company

Keyword: Obesity
Link ID: 17552 - Posted: 11.29.2012

Scicurious Guest Writer, Nicole Baganz! 4:02 PM. It took every ounce of energy I had to drag myself to the bathroom. Arriving in the room that is located 2 feet from my bed felt like a victory. I rifled through the medicine cabinet, stuck the thermometer in my mouth and collapsed on the bathroom floor. 103.2° F. Yep, I’m sick. Sleepiness. Fatigue. Loss of appetite and motivation. Lethargy. Leave me alone. We all know what it feels like to be sick. Clinicians collectively describe this group of symptoms as “sickness behavior”. Evolutionarily speaking, the idea that the immune system would produce these symptoms makes sense. An organism infected with a pathogenic bug should retreat from its social group to protect others from the spread of infection. The organism essentially shuts down in order to send every ounce of energy to the immune system to battle the bug that has invaded the body’s cells. This sickness state would facilitate recovery of the organism and also protect the community from the spread of the infection by limiting the interaction of the infected party from its entire social group. All of the symptoms of sickness behavior are displayed not only by people who have an infection, but also by those who have been diagnosed with Major Depressive Disorder (MDD). Could sickness behavior and MDD be linked? What happens in the brain to produce sickness behaviors, and how might these relate to depression? Mice are good models for scientists to use to study the effect of immune system activation on brain function and behavior (research studies that subject people to infectious agents before probing their brains in the name of science draw few willing volunteers). Laboratory mice also display sickness behavior when their immune systems are turned on. Sick rodents sleep more, eat less, and lose interest in drinking sugary water (usually a scrumptious treat for mice). They also stop interacting socially – mice are, by nature, very social creatures that like to sniff, groom, lick and cuddle up to their roommates. © 2012 Scientific American

Keyword: Depression
Link ID: 17551 - Posted: 11.29.2012

By David Levine People with depression or other mental illnesses often report trouble sleeping, daytime drowsiness and other sleep-related issues. Now a growing body of research is showing that treating sleep problems can dramatically improve psychiatric symptoms in many patients. Much of the latest work illustrates how sleep apnea, a common chronic condition in which a person repeatedly stops breathing during sleep, may cause or aggravate psychiatric symptoms. In past years sleep apnea has been linked to depression in small studies and limited populations. Now a study by the Centers for Disease Control and Prevention strengthens that connection. The CDC analyzed the medical records of nearly 10,000 American adults with sleep apnea. Men diagnosed with this disorder had twice the risk of depression—and women five times the risk—compared with those without sleep apnea. Writing in the April issue of Sleep, lead author Anne G. Wheaton and her colleagues speculate that in addition to interrupting sleep, the oxygen deprivation induced by sleep apnea could harm cells and disrupt normal brain functioning. Treating this disorder shows promise for reducing symptoms of depression, a recent study at the Cleveland Clinic suggests. In the experiment, patients went to bed wearing a mask hooked up to a machine that increases air pressure in their throat. The increased pressure prevents the airway from collapsing, which is what causes breathing to cease in most cases of this disorder. Using this machine, psychiatrist Charles Bae and his colleagues treated 779 patients who had been diagnosed with sleep apnea. After an average of 90 days of sleeping with the machine, all the patients scored lower on a common depression survey than before the treatment—regardless of whether they had a prior diagnosis of depression or were taking an antidepressant. The data were presented in June at the SLEEP 2012 conference in Boston. © 2012 Scientific American

Keyword: Sleep; Depression
Link ID: 17550 - Posted: 11.28.2012

High-resolution real-time images show in mice how nerves may be damaged during the earliest stages of multiple sclerosis. The results suggest that the critical step happens when fibrinogen, a blood-clotting protein, leaks into the central nervous system and activates immune cells called microglia. "We have shown that fibrinogen is the trigger," said Katerina Akassoglou, Ph.D., an associate investigator at the Gladstone Institute for Neurological Disease and professor of neurology at the University of California, San Francisco, and senior author of the paper published online in Nature Communications. Multiple sclerosis, or MS, is thought to be an autoimmune disease in which cells that normally protect the body against infections attack nerve cells in the brain and spinal cord, often leading to problems with vision, muscle strength, balance and coordination, thinking and memory. Typically during MS, the immune cells destroy myelin, a protective sheath surrounding nerves, and eventually leading to nerve damage. The immune attack also causes leaks in the blood-brain barrier, which normally separates the brain from potentially harmful substances in the blood. "Dr. Akassoglou has focused on the role of the blood-brain barrier leak in MS and has discovered that leakage of the blood clotting protein fibrinogen can trigger brain inflammation," said Ursula Utz, Ph.D., M.B.A., a program director at NIH's National Institute of Neurological Disorders and Stroke (NINDS). Microglia are cells traditionally thought to control immunity in the nervous system. Previous studies suggested that leakage of fibrinogen activates microglia.

Keyword: Multiple Sclerosis; Glia
Link ID: 17549 - Posted: 11.28.2012