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by Julia Sklar IT IS a nightmare situation. A person diagnosed as being in a vegetative state has an operation without anaesthetic because they cannot feel pain. Except, maybe they can. Alexandra Markl at the Schön clinic in Bad Aibling, Germany, and colleagues studied people with unresponsive wakefulness syndrome (UWS) – also known as vegetative state – and identified activity in brain areas involved in the emotional aspects of pain. People with UWS can make reflex movements but can't show subjective awareness. There are two distinct neural networks that work together to create the sensation of pain. The more basic of the two – the sensory-discriminative network – identifies the presence of an unpleasant stimulus. It is the affective network that attaches emotions and subjective feelings to the experience. Crucially, without the activity of the emotional network, your brain detects pain but won't interpret it as unpleasant. Using PET scans, previous studies have detected activation in the sensory-discriminative network in people with UWS but their findings were consistent with a lack of subjective awareness, the hallmark of the condition. Now Markl and her colleagues have found evidence of activation in the affective or emotional network too (Brain and Behavior, doi.org/kfs). © Copyright Reed Business Information Ltd.

Keyword: Consciousness; Pain & Touch
Link ID: 17839 - Posted: 02.23.2013

Regina Nuzzo Say the word 'rutabaga', and you have just performed a complex dance with many body parts — lips, tongue, jaw and larynx — in a flash of time. Yet little is known about how the brain coordinates these vocal-tract movements to keep even the clumsiest of us from constantly tripping over our own tongues. A study of unprecedented detail now provides a glimpse into the neural codes that control the production of smooth speech. The results help to clarify how the brain uses muscles to organize sounds and hint at why tongue twisters are so tricky. The work is published today in Nature1. Most neural information about the vocal tract has come from watching people with brain damage or from non-invasive imaging methods, neither of which provide detailed data in time or space2, 3. A team of US researchers has now collected brain-activity data on a scale of millimetres and milliseconds. The researchers recorded brain activity in three people with epilepsy using electrodes that had been implanted in the patients' cortices as part of routine presurgical electrophysiological sessions. They then watched to see what happened when the patients articulated a series of syllables. Sophisticated multi-dimensional statistical procedures enabled the researchers to sift through the huge amounts of data and uncover how basic neural building blocks — patterns of neurons firing in different places over time — combine to form the speech sounds of American English. The patterns for consonants were quite different from those for vowels, even though the parts of speech “use the exact same parts of the vocal tract”, says author Edward Chang, a neuroscientist at the University of California, San Francisco. © 2013 Nature Publishing Group

Keyword: Language
Link ID: 17838 - Posted: 02.23.2013

by Sara Reardon Like the musicians in an orchestra, our lips, tongue and vocal cords coordinate with one another to pronounce sounds in speech. A map of the brain regions that conduct the process shows how each is carefully controlled – and how mistakes can slip into our speech. It's long been thought that the brain coordinates our speech by simultaneously controlling the movement of these "articulators". In the 1860s, Alexander Melville Bell proposed that speech could be broken down in this way and designed a writing system for deaf people based on the principle. But brain imaging had not had the resolution to see how neurons control these movements – until now. Using electrodes implanted in the brains of three people to treat their epilepsy, Edward Chang and his colleagues at the University of California mapped brain activity in each volunteer's motor cortex as they pronounced words in American English. The team had expected that each speech sound would be controlled by a unique collection of neurons, and so each would map to a different part of the brain. Instead, they found that the same groups of neurons were activated for all sounds. Each group controls muscles in the tongue, lips, jaw and larynx. The neurons – in the sensorimotor cortex – coordinated with one another to fire in different combinations. Each combination resulted in a very precise placing of the articulators to generate a given sound. Surprisingly, although each articulator can theoretically take on an almost limitless range of shapes, the neurons imposed strict limits on the range of possibilities. © Copyright Reed Business Information Ltd.

Keyword: Language
Link ID: 17837 - Posted: 02.23.2013

By ANAHAD O'CONNOR Depression may lower the effectiveness of the shingles vaccine, a new study found. The research showed that adults with untreated depression who received the vaccine mounted a relatively weak immune response. But those who were taking antidepressants showed a normal response to the vaccine, even when symptoms of depression persist. Shingles, an acute and painful rash, strikes a million Americans each year, mostly older adults. Health officials recommend that those over 60 get vaccinated against the condition, which is caused by reactivation of the same virus that causes chickenpox, varicella-zoster. In the new study, published in the journal Clinical Infectious Diseases, researchers followed a group of 92 older men and women for two years. Forty of the subjects had a major depressive disorder; they were matched with 52 control subjects of similar age. The researchers measured their immune responses to the shingles vaccine and a placebo shot. Compared with the control patients, those with depression were poorly protected by the vaccine. But the patients who were being treated for their depression showed a boost in immunity — what the researchers called a “normalization” of the immune response. It is unclear why that was the case. The authors of the study speculated that treatment of older people with depression might increase the effectiveness of the flu shot and other vaccines as well. Copyright 2013 The New York Times Company

Keyword: Depression; Neuroimmunology
Link ID: 17836 - Posted: 02.23.2013

By Janet Raloff Hospitals rush newborns into a neonatal intensive care unit when those babies are struggling to survive. Although NICUs offer tender and vigilant care, many of the devices they rely on can expose their tiny patients to a relatively large dose of a hormone-mimicking pollutant, bisphenol A. Newborns in intensive care excrete BPA, on average, at levels of around 17.8 micrograms per liter — well above the 0.45 µg/l typical of healthy infants, researchers report in the March Pediatrics. One of the most reliable indicators of BPA exposure was the level of care that a baby received, reflected by the number of devices used to deliver that care, notes nurse and exposure-science researcher Susan Duty of Simmons College in Boston. Breathing tubes, intravenous drug delivery lines and enclosed incubators are plastic, and several types of plastic can contain BPA. Although researchers have not figured out what doses of BPA cause toxicity in people, several studies have linked elevated prenatal exposures to later behavioral problems (SN Online: 7/16/12) and moodiness (SN: 11/7/09, p. 12) in young children. Animal studies have also linked BPA exposure during development to feminization in males and risks of later hypertension and diabetes. Duty’s team studied 55 infants, each of whom spent at least three days in a NICU in the Boston area, and most of whom had been born prematurely or were for other reasons very small. The researchers measured BPA in the breast milk and formula that these tiny babies consumed. Both nutritional sources had small, comparable amounts of BPA. © Society for Science & the Public 2000 - 2013

Keyword: Development of the Brain; Neurotoxins
Link ID: 17835 - Posted: 02.23.2013

Sandrine Ceurstemont, editor, New Scientist TV It's the sequel to fertilisation: the brains of unborn babies have now been imaged in action, showing how connections form. This fMRI movie, produced by Moriah Thomason from Wayne State University in Detroit, Michigan, shows a fly-through of several fetuses in their third trimester. By comparing the scans at slightly different stages of development, Thomason was able to pinpoint when different parts of the brain wire up. "The connection strength increases with fetal age," writes Thomason. By identifying how brain connectivity normally develops, the scans could help diagnose and treat conditions like schizophrenia and autism before birth. For more on this research, read our full-length news story, "First snaps made of fetal brains wiring themselves up". © Copyright Reed Business Information Ltd.

Keyword: Development of the Brain; Brain imaging
Link ID: 17834 - Posted: 02.23.2013

Canadian researchers have found out how to restore normal vision to kittens with a lazy eye without using an eye patch. The cure was relatively simple — putting the kittens in complete darkness for 10 days. Once the kittens were returned to daylight, they regained normal vision in the lazy eye within a week, reported researchers at Dalhousie University in Halifax in the journal Current Biology this month. Lazy eye is a condition where the brain effectively turns off one eye. It affects about four per cent of the population in humans, and the most common treatment is fix the vision problem (for example, by using glasses) and then patch the good eye, forcing the person to use their bad eye. Kevin Duffy, a neuroscientist who co-authored the new study, told CBC's Quirks & Quarks that the condition is typically the result of a vision problem such as a cataract, a misalignment of the eyes, or poor focus in one eye, which then causes the brain to develop abnormally. "If the eye is providing abnormal vision, then the circuits that connect to that eye are going to develop abnormally," he said. The brain "becomes effectively disconnected." © CBC 2013

Keyword: Vision; Development of the Brain
Link ID: 17833 - Posted: 02.23.2013

By Susan Milius Slight electric fields that form around flowers may lure pollinators much as floral colors and fragrances do. In lab setups, bumblebees learned to distinguish fake flowers by their electrical fields, says sensory biologist Daniel Robert at the University of Bristol in England. Combining an electrical charge with a color helped the bees learn faster, Robert and his colleagues report online February 21 in Science. Plants, a bit like lightning rods, tend to conduct electrical charges to the ground, Robert says. And bees pick up a positive charge from the atmosphere’s invisible rain of charged particles. “Anything flying through the air, whether it’s a baseball, 767 jumbo jet, or a bee, acquires a strong positive electrostatic charge due to interaction with air molecules,” says Stephen Buchmann of the University of Arizona in Tucson. Robert and his colleagues checked whether bees could choose flowers based solely on the electric fields the plants produce. Purple metal disks (encased in plastic so as not to shock bees) stood in for flowers. Half of them, wired for 30 volts, held sips of sugar water. The unwired ones offered a bitter quinine solution that bees don’t like. Bombus terrestris bumblebees learned to choose sweet, wired disks more than 80 percent of the time. When researchers unplugged the wired disks, the bees bumbled, scoring sugar only by chance. © Society for Science & the Public 2000 - 2013

Keyword: Vision
Link ID: 17832 - Posted: 02.23.2013

By Tina Hesman Saey Like the sun, insulin levels rise and fall in a daily rhythm. Disrupting that cycle may contribute to obesity and diabetes, a new study suggests. Many body systems follow a daily clock known as a circadian rhythm. Body temperature, blood pressure and the release of many hormones are on circadian timers. But until now, no one had shown that insulin — a hormone that helps control how the body uses sugars for energy — also has a daily cycle. Working with mice, researchers at Vanderbilt University in Nashville have found that rodents are more sensitive to insulin’s effects at certain times of day. Disrupting the animals’ circadian timers interferes with the hormone’s daily rise and fall and makes mice prone to obesity. If the findings hold up in humans, they could help explain why people who work night shifts tend to be overweight and suffer health problems. The discovery may also tie the obesity epidemic in part to staying up late and eating at the wrong time. Many people had thought that it was best for the body to maintain insulin at a relatively constant level, says Carl Johnson, a circadian biologist who led the new study. “But that’s not how organisms have adapted,” he says. Since the environment cycles through light and dark, body processes often coordinate with that rhythm. To uncover insulin’s natural rhythm, Johnson and his colleagues performed an “insulin clamp” procedure on mice. The clamp infuses glucose or insulin around the clock into mice that are moving freely in their cages. Measuring how much insulin or glucose the mice need to maintain constant blood sugar levels tells the researchers how responsive the animals are to the hormone at any given time of day. © Society for Science & the Public 2000 - 2013

Keyword: Biological Rhythms; Obesity
Link ID: 17831 - Posted: 02.23.2013

by Michael Balter Despite recent progress toward sexual equality, it's still a man's world in many ways. But numerous studies show that when it comes to language, girls start off with better skills than boys. Now, scientists studying a gene linked to the evolution of vocalizations and language have for the first time found clear sex differences in its activity in both rodents and humans, with the gene making more of its protein in girls. But some researchers caution against drawing too many conclusions about the gene's role in human and animal communication from this study. Back in 2001, the world of language research was rocked by the discovery that a gene called FOXP2 appeared to be essential for the production of speech. Researchers cautioned that FOXP2 is probably only one of many genes involved in human communication, but later discoveries seemed to underscore its importance. For example, the human version of the protein produced by the gene differs by two amino acids from that of chimpanzees, and seems to have undergone natural selection since the human and chimp lineages split between 5 million and 7 million years ago. (Neandertals were found to have the same version as Homo sapiens, fueling speculation that our evolutionary cousins also had language). In the years since, FOXP2 has been implicated in the vocalizations of other animals, including mice, singing birds, and even bats. During this same time period, a number of studies have confirmed past research suggesting that young girls learn language faster and earlier than boys, producing their first words and sentences sooner and accumulating larger vocabularies faster. But the reasons behind such findings are highly controversial because it is difficult to separate the effects of nature versus nurture, and the differences gradually disappear as children get older. © 2010 American Association for the Advancement of Science

Keyword: Language; Sexual Behavior
Link ID: 17830 - Posted: 02.20.2013

by Virginia Morell Every bottlenose dolphin has its own whistle, a high-pitched, warbly "eeee" that tells the other dolphins that a particular individual is present. Dolphins are excellent vocal mimics, too, able to copy even quirky computer-generated sounds. So, scientists have wondered if dolphins can copy each other's signature whistles—which would be very similar to people saying each others' names. Now, an analysis of whistles recorded from hundreds of wild bottlenose dolphins confirms that they can indeed "name" each other, and suggests why they do so—a discovery that may help researchers translate more of what these brainy marine mammals are squeaking, trilling, and clicking about. "It's a wonderful study, really solid," says Peter Tyack, a marine mammal biologist at the University of St. Andrews in the United Kingdom who was not involved in this project. "Having the ability to learn another individual's name is … not what most animals do. Monkeys have food calls and calls that identify predators, but these are inherited, not learned sounds." The new work "opens the door to understanding the importance of naming." Scientists discovered the dolphins' namelike whistles almost 50 years ago. Since then, researchers have shown that infant dolphins learn their individual whistles from their mothers. A 1986 paper by Tyack did show that a pair of captive male dolphins imitated each others' whistles, and in 2000, Vincent Janik, who is also at St. Andrews, succeeded in recording matching calls among 10 wild dolphins "But without more animals, you couldn't draw a conclusion about what was going on," says Richard Connor, a cetacean biologist at the University of Massachusetts, Dartmouth. Why, after all, would the dolphins need to copy another dolphin's whistle? © 2010 American Association for the Advancement of Science

Keyword: Language; Evolution
Link ID: 17829 - Posted: 02.20.2013

Stephen S. Hall Male sexual dysfunction is never pretty, even in nematodes. In normal roundworm courtship, a slender male will sidle up to a plump hermaphrodite, make contact, and then initiate a set of steps leading up to insemination: a sinuous backwards motion as he searches for the sexual cleft, a pause to probe, and finally the transfer of sperm. The whole business is usually over in a couple of minutes. “It's very slithery, and affectionate,” says Cornelia Bargmann, who has been observing the behaviour of this particular worm, Caenorhabditis elegans, for 25 years. Last October, scientists in Bargmann's laboratory at the Rockefeller University, New York, reported the discovery of a gene that seems to be crucial to successful mating. Disrupting the action of this gene causes male sexual confusion of almost epic pathos: nematodes with certain mutations poke tentatively at an inert hermaphrodite, making confused, fruitless curlicues around the potential mate. Occasionally the mutant male succeeds, but often he literally falls off the job and begins the search anew for a mate. Jennifer Garrison, a postdoc of Bargmann's who tracked the behaviour of these males, just shakes her head as she replays the scene on her computer screen. “Really sad,” she says. There are two punchlines to this story of thwarted invertebrate mating. One is the charming squeamishness with which Bargmann describes it, hesitating at words such as “vulva” and “spicule” and other anatomical gewgaws of roundworm reproduction. “As a well-brought-up Southern girl,” she says with a laugh, “it's still difficult to talk about this!” © 2013 Nature Publishing Group

Keyword: Genes & Behavior; Development of the Brain
Link ID: 17828 - Posted: 02.20.2013

By Steven Ross Pomeroy Everyone enjoys the occasional practical joke – assuming the gag isn’t mean-spirited or overly perilous, even the prank’s poor victim can appreciate the punch line! I’m sure you have your favorites: gluing dollars to sidewalks, filling your co-worker’s office with balloons, moving your roommate’s bed to the basement… while he’s sleeping in it. More typical stunts may employ whoopee cushions, fake vomit, and hand buzzers, but honestly, those are a tad sophomoric and overdone. Thus, in an effort to elevate the standard of stunts, I’d like to present a gag that makes use not of stink bombs, but of science. How to implant false memories in your friends, in four steps: In The Demon-Haunted World, Carl Sagan argued that implanting false memories in people is not only possible, but is actually pretty easy when attempted in the proper settings with a gullible subject, He cited as examples people who, at the urging of therapists or hypnotists, genuinely start to believe that they’d been abducted by UFOs or falsely remember being abused as a child. For these people, the distinction between memory and imagination becomes blurred, and events that never actually took place become sewn into their memories as real events. They can even describe these false remembrances incredibly vividly – as if they actually happened! “Memory can be contaminated,” Sagan wrote. “False memories can be implanted even in minds that do not consider themselves vulnerable and uncritical.” © 2013 Scientific American

Keyword: Learning & Memory
Link ID: 17827 - Posted: 02.20.2013

By Hristio Boytchev, Believing that brains can be trained through the use of specialized computer programs, researchers are focusing on helping people with schizophrenia, which can cause them to hear imagined voices or believe that others are controlling or plotting against them. There are medications for the often-disabling disorder, but they have severe side effects and don’t get rid of all symptoms; many people will not stick with the drugs. A California company, Posit Science, is developing a computer game that it hopes will become the first to earn approval from the Food and Drug Administration for treating schizophrenia. The idea comes from Michael Merzenich, an emeritus professor of neuroscience at the University of California at San Francisco and a co-founder of Posit Science. Merzenich is something of a living legend in neuroscience, a co-inventor of cochlear implants and one of the pioneers of the theory of neuroplasticity, which asserts that the brain continues to develop throughout a lifetime. Treating schizophrenia with brain training is based on the theo­ry that the confusion and fear the disease creates may occur because the brain’s expectations about what will happen do not match up with what actually happens. That disconnect might be traced to a problem with verbal and auditory processing of information, something that brain training targets. © 1996-2013 The Washington Post

Keyword: Schizophrenia; Learning & Memory
Link ID: 17826 - Posted: 02.19.2013

Diet pop and other artificially sweetened products may cause us to eat and drink even more calories and increase our risk for obesity and Type 2 diabetes, researchers are learning. Former McGill University researcher Dana Small specializes in the neuropsychology of flavour and feeding at Yale University in New Haven, Conn. Small said there's mounting evidence that artificial sweeteners have a couple of problematic effects. Sugar substitutes such as sucralose and aspartame are more intensely sweet than sugar and may rewire taste receptors so less sweet, healthier foods aren't as enjoyable, shifting preferences to higher calorie, sweeter foods, she said. Small and some other researchers believe artificial sweeteners interfere with brain chemistry and hormones that regulate appetite and satiety. For millennia, sweet taste signalled the arrival of calories. But that's no longer the case with artificial sweeteners. "The sweet taste is no longer signalling energy and so the body adapts," Small said in an interview with CBC News. "It's no longer going to release insulin when it senses sweet because sweet now is not such a good predictor of the arrival of energy." Susan Swithers, a psychology professor at Purdue University in West Lafayette, Ind., studies behavioural neuroscience. "Exposure to high-intensity sweeteners could change the way that sweet tastes are processed," she says. © CBC 2013

Keyword: Obesity; Chemical Senses (Smell & Taste)
Link ID: 17825 - Posted: 02.19.2013

By Ingrid Wickelgren How many times have you arrived someplace but had no memory of the trip there? Have you ever been sitting in an auditorium daydreaming, not registering what the people on stage are saying or playing? We often spin through our days lost in mental time travel, thinking about something from the past, or future, leaving us oblivious to what is happening right around us right now. In doing so, we miss much of life. We also make ourselves relatively miserable, and prone to poor performance and mishaps. peaceful scene, village by the water. The opposite mental state, mindfulness, is a calm, focused awareness of the present. Cultivating that state is associated with improvements in both mental and physical health, as you will learn from the current cover story of Scientific American Mind (see “Mindfulness Can Improve Your Attention and Health” by Amishi P. Jha). It can even ameliorate mental illness. It turns out that mindfulness training works in large part by training our ability to pay attention. As we learn to focus on the here and now, we also learn to manipulate our mental focus more generally. The ability to direct our own minds at will means we control what we think about. It is no wonder that honing such a skill can make us happier. It can also boost the performance of soldiers, surgeons, athletes and many others who need to maintain a tight focus on what they are doing. Some people are naturally more mindful than others, but it is possible to train yourself to enter this state more often. Simple exercises performed as little as 12 minutes daily can help you become more mindful. For a sample exercise, watch this video “Learn to Live in the Now.” © 2013 Scientific American

Keyword: Attention
Link ID: 17824 - Posted: 02.19.2013

By Sandra G. Boodman, Ian Liu’s back was killing him — and no matter what he tried, it wasn’t getting better. The 39-year-old Coast Guard officer assumed he had wrenched his back caring for his infant son, not surprising given his long history of lower back problems. But this time, the pain was much more intense and persistent, and neither physical therapy nor painkillers seemed to help. For more than a month, Liu shuttled between two Washington area military hospitals, searching for an explanation and, especially, relief. “It was the worst pain I’d ever had,” Liu recalled. A series of tests failed to explain his deteriorating condition, which stumped the medical personnel who treated him. It was only after Liu’s wife confided that he sometimes seemed disoriented that a doctor looked beyond the obvious problem and discovered the source of Liu’s pain. The cause turned out to be unrelated to his orthopedic history — and far more serious than a bad back. Liu first noticed the pain on a Friday night, Dec. 3, 2004, after he finished bathing the youngest of his three sons. “I assumed it was just from bending over the tub,” recalled Liu, who figured it would improve with time, as such problems had in the past. But the next day, his pain was worse, and as he wheeled his shopping cart around a Northern Virginia commissary, Liu was glad he had something to lean on. © 1996-2013 The Washington Post

Keyword: Pain & Touch
Link ID: 17823 - Posted: 02.19.2013

By Alan Boyle, Science Editor, NBC News BOSTON — The brain-mapping project that the Obama administration wants to facilitate isn't necessarily aimed at adding billions of dollars to the money already being spent on research, according to the scientists who inspired the idea. Instead, it's aimed at harnessing new technologies to uncover the secrets of neural function less expensively and more completely. "We can bring down the cost and increase the quality of the technology," said Harvard geneticist George Church, one of the researchers who proposed the Brain Activity Map Project last year. "We are trying to work with current funding [levels] to bring down the cost." The New York Times reported on Monday that the White House has embraced the idea of having the Office of Science and Technology Policy spearhead the project, with participation by the National Institutes of Health and other federal agencies. The federal initiative is to be unveiled as early as next month, the Times quoted its sources as saying. The roots of the project go back months if not years earlier: The goals of the BAM Project were outlined last June in a white paper appearing in the journal Neuron. The researchers proposed a 15-year international effort to map the functions of the brain's complex neural circuitry to an unprecedented degree — using traditional tools such as magnetic resonance imaging in combination with novel technologies such as nanosensors and wireless fiber-optic probes that can be implanted into the brain, and genetically engineered cells that can be linked up with brain cells to record their activity. © 2013 NBCNews.com

Keyword: Brain imaging
Link ID: 17822 - Posted: 02.19.2013

By SINDYA N. BHANOO Humans and many other mammals see and hear in stereo. But what about smell? “People have wondered for a long time whether smell has this component as well,” said Kenneth C. Catania, a biologist at Vanderbilt University. Now he and colleagues report in the journal Nature Communications that common moles, which are blind, have the ability and use it to swiftly locate prey. Dr. Catania created a chamber with food wells spaced around a semicircle and watched as moles detected the food. The chamber was sealed, so changes in air pressure would indicate that the animals were sniffing. Moving their noses back and forth, the moles zeroed in on the food in less than five seconds. Dr. Catania then blocked one of the moles’ nostrils with a plastic tube. When the left nostril was blocked, the moles veered off to the right, and when the right was blocked, they veered to left. Although they were still able to find the food, it took them much longer. To confirm that the moles use stereo sniffing, Dr. Catania put plastic tubes in both nostrils and then crossed them. This confused the moles, causing them to think that food to their right was actually located to their left. But their response confirmed that the moles in fact use stereo sniffing, Dr. Catania said. Previous research indicates that rats can smell in stereo, and there are suggestions that sharks and ants can, too. “The jury is still out on how many animals can do this, and that will tell us how primitive this is,” Dr. Catania said. “If only a few animals do it, then it may have evolved recently.” So can humans smell in stereo? Unlikely, he said. © 2013 The New York Times Company

Keyword: Chemical Senses (Smell & Taste)
Link ID: 17821 - Posted: 02.19.2013

By Rachel Ehrenberg BOSTON — For the first time, researchers have snapped pictures of mouse inner ear cells using an approach that doesn’t damage tissue or require elaborate dyes. The approach could offer a way to investigate hearing loss — the most common sensory deficit in the world — and may help guide the placement of cochlear devices or other implants. Inner ear damage and the deafness that results have long challenged scientists. The small delicate cochlea and associated parts are encased in the densest bone in the body and near crucial anatomical landmarks, including the jugular vein, carotid artery and facial nerve, which make them difficult to access. With standard anatomical imaging techniques such as MRI, the inner ear just looks like a small grey blob. “We can’t biopsy it, we can’t image it, so it’s very difficult to figure out why people are deaf,” said ear surgeon and neuroscientist Konstantina Stankovic of the Massachusetts Eye and Ear Infirmary in Boston. Stankovic and her colleagues took a peek at inner ear cells using an existing technique called two-photon microscopy. This approach shoots photons at the target tissue, exciting particular molecules that then emit light. The researchers worked with mice exposed to 160 decibels of sound for two hours —levels comparable to the roaring buzz of a snowmobile or power tools. Then they removed the rodents’ inner ears, which includes the spiraled, snail-shaped cochlea and other organs. Instead of cutting into the cochlea, the researchers peered through the “round window” — a middle ear opening covered by a thin membrane that leads to the cochlea. © Society for Science & the Public 2000 - 2013

Keyword: Hearing; Brain imaging
Link ID: 17820 - Posted: 02.19.2013