A gene associated with a rare form of progressive deafness in males has been identified by an international team of researchers funded by the National Institute on Deafness and Other Communication Disorders. The gene, PRPS1, appears to be crucial in inner ear development and maintenance. The findings are published in the December 17 early online issue of the American Journal of Human Genetics. The gene is associated with DFN2, a progressive form of deafness that primarily affects males. Boys with DFN2 begin to lose their hearing in both ears roughly between the ages of 5 and 15, and over the course of several decades will experience hearing loss that can range from severe to profound. Their mothers, who carry the defective PRPS1 gene, may experience hearing loss as well, but much later in life and in a milder form. Families with DFN2 have been identified in the United States, Great Britain, and China. The NIDCD-funded researchers led by Xue Zhong Liu, M.D., Ph.D., of the University of Miami Miller School of Medicine, discovered that the PRPS1 gene encodes the enzyme phosphoribosylpyrophosphate (PRPP) synthetase 1, which produces and regulates PRPP (phospho-ribosylpyrophosphate), and appears to play a key role in inner ear development and maintenance. The four mutations identified in the PRPS1 gene cause a decrease in the production of the PRPP synthetase 1 protein that results in defects in sensory cells (called hair cells) in the inner ear, and eventually leads to progressive deafness.

Keyword: Hearing; Genes & Behavior
Link ID: 13581 - Posted: 12.19.2009

by Carl Zimmer When Samuel Morse established the first commercial telegraph, in 1844, he dramatically changed our expectations about the pace of life. One of the first telegraph messages came from that year’s Democratic National Convention in Baltimore, where the delegates had picked Senator Silas Wright as their vice presidential nominee. The president of the convention telegraphed Wright in Washington, D.C., to see if he would accept. Wright immediately wired back: No. Incredulous that a message could fly almost instantly down a wire, the delegates adjourned and sent a flesh-and-blood committee by train to confirm Wright’s response—which was, of course, the same. From such beginnings came today’s high-speed, networked society. Less famously but no less significantly, the telegraph also transformed the way we think about the pace of our inner life. Morse’s invention debuted just as researchers were starting to make sense of the nervous system, and telegraph wires were an inspiring model of how nerves might work. After all, nerves and telegraph wires were both long strands, and they both used electricity to transmit signals. Scientists knew that telegraph signals did not travel instantaneously; in one experiment, it took a set of dots and dashes a quarter of a second to travel 900 miles down a telegraph wire. Perhaps, the early brain investigators considered, it took time for nerves to send signals too. And perhaps we could even quantify that time. The notion that the speed of thought could be measured, just like the density of a rock, was shocking. Yet that is exactly what scientists did. In 1850 German physiologist Hermann von Helmholtz attached wires to a frog’s leg muscle so that when the muscle contracted it broke a circuit. He found that it took a tenth of a second for a signal to travel down the nerve to the muscle.

Keyword: Miscellaneous
Link ID: 13580 - Posted: 06.24.2010

By Nathan Seppa It looks like nearsightedness is on the rise in the United States. Researchers tapped into a wide-ranging health survey to rate vision in the population in the early 1970s and roughly 30 years later. They compared eyesight information for more than 4,400 people tested in 1971 and 1972 with data from another set of 8,300 people tested from 1999 to 2004. This broad survey showed that 25 percent of those examined in the early 1970s were deemed to be nearsighted, compared with 42 percent examined three decades later, the researchers report in the December Archives of Ophthalmology. That’s an increase of 66 percent. Myopia severity also increased, with moderate nearsightedness doubling between the two time periods and severe cases, although uncommon, also rising sharply. Mild myopia cases increased slightly, from about 13 percent to 18 percent. This group included some people who did not need corrective lenses, says study coauthor Susan Vitale, an epidemiologist at the National Eye Institute in Bethesda, Md. When analyzing the more recent eye-exam data, the scientists used only diagnoses that were made with the same technology used in the 1970s — mainly standard eye tests and trial lenses. Including diagnoses made with more advanced technology that has become available only recently might have biased the comparison, Vitale says.. The cause of nearsightedness is poorly understood. Past research has linked added risk to both a genetic predisposition to nearsightedness and to excessive amounts of near work, the kind of tasks that require peering at written words or small objects. © Society for Science & the Public 2000 - 2009

Keyword: Vision
Link ID: 13579 - Posted: 06.24.2010

By Megan Talkington Many animals test their legs and totter forth only hours after they are born, but humans need a year before they take their first, hesitant steps. Is something fundamentally different going on in human babies? Maybe not. A new study shows that the time it takes for humans and all other mammals to start walking fits closely with the size of their brains. In past studies to develop a new animal model for the brain events that support motor development, neurophysiologist Martin Garwicz of Lund University in Sweden and his colleagues discovered that the schedules by which ferrets and rats acquire various motor skills, such as crawling and walking, are strikingly similar to each other; the progress simply happens faster for rats. That made them wonder how similar the timing of motor development might be among mammals in general. They compared the time between conception and walking in 24 species and looked at how well this duration correlated with a range of variables, including gestation time, adult body mass, and adult brain mass. As they report in this week's issue of PNAS, brain mass accounts for the vast majority (94%) of the variance in walking time between species. Species with larger brains, such as humans, tend to take longer to learn to walk. Strikingly, a model based on adult brain mass and walking time in the other 23 species almost perfectly predicts when humans begin to walk. "We've always considered humans the exception," Garwicz says, "But in fact, we start walking at exactly the time that would be expected from all other walking mammals." © 2009 American Association for the Advancement of Science

Keyword: Development of the Brain; Evolution
Link ID: 13578 - Posted: 06.24.2010

By Katherine Harmon In patients who have survived severe brain damage, judging the level of actual awareness has proved a difficult process. And the prognosis can sometimes mean the difference between life and death. New research suggests that some vegetative patients are capable of simple learning—a sign of consciousness in many who had failed other traditional cognitive tests. To determine whether patients are in a minimally conscious state (in which there is some evidence of perception or intentional movement) or have sunk into a vegetative state (in which neither exists), doctors have traditionally used a battery of tests and observations. Many of them require some subjective interpretation, such as deciding whether a patient’s movements are purposeful or just random. “We want to have an objective way of knowing whether the other person has consciousness or not,” says Mariano Sigman, who directs the Integrative Neuroscience Laboratory at the University of Buenos Aires. That desire stems in part from surprising neuroimaging work that showed that some vegetative patients, when asked to imagine performing physical tasks such as playing tennis, still had activity in premotor areas of their brains. In others, verbal cues sparked language sectors. A recent study found that about 40 percent of vegetative state diagnoses are incorrect. To explore possible tests of consciousness in patients, Sigman and his colleagues turned to classical conditioning: they sounded a tone and then sent a light puff of air to the patient’s eye. The air puff would cause a patient to blink or flinch the eye, but after repeated trials over half an hour, many patients would begin to anticipate the puff, blinking an eye after only hearing the tone. © 1996-2009 Scientific American Inc.

Keyword: Brain imaging
Link ID: 13577 - Posted: 06.24.2010

By Mark Pothier In the long and tortured debate over drug policy, one of the strangest episodes has been playing out this fall in the United Kingdom, where the country’s top drug adviser was recently fired for publicly criticizing his own government’s drug laws. The adviser, Dr. David Nutt, said in a lecture that alcohol is more hazardous than many outlawed substances, and that the United Kingdom might be making a mistake in throwing marijuana smokers in jail. His comments were published in a press release in October, and the next day he was dismissed. The buzz over his sacking has yet to subside: Nutt has become the talk of pubs and Parliament, as well as the subject of tabloid headlines like: “Drug advisor on wacky baccy?” But behind Nutt’s words lay something perhaps more surprising, and harder to grapple with. His comments weren’t the idle musings of a reality-insulated professor in a policy job. They were based on a list - a scientifically compiled ranking of drugs, assembled by specialists in chemistry, health, and enforcement, published in a prestigious medical journal two years earlier. The list, printed as a chart with the unassuming title “Mean Harm Scores for 20 Substances,” ranked a set of common drugs, both legal and illegal, in order of their harmfulness - how addictive they were, how physically damaging, and how much they threatened society. Many drug specialists now consider it one of the most objective sources available on the actual harmfulness of different substances. © 2009 NY Times Co

Keyword: Drug Abuse
Link ID: 13576 - Posted: 06.24.2010

By Emily Sohn Blue whales' songs are hauntingly deep, filled with extraterrestrial vibratos, and utterly mysterious. Despite many attempts to interpret them, scientists still don't know what the world's largest animals are saying. Now, the mystery only thickens. For decades, blue whales have been singing with increasingly deeper voices, reports a new study. In some cases, the pitch of their songs has dropped by more than 30 percent. Frustrated researchers cannot yet explain why. "It's a worldwide phenomenon," said Mark McDonald, an ocean acoustician and independent researcher in Bellvue, Colo. "All blue whales are shifting their frequencies downward. They are all going in the same direction, and we really don't understand it." "Maybe by putting this data out there," he added, "someone will have a eureka moment and see something that really explains this." McDonald first suspected something was going on about eight years ago, when he started setting up underwater detectors to study blue whales across the Pacific Ocean. To get the devices to work, he and colleagues noticed that they had to shift the detector frequencies downward every year. At the time, they didn't know if something was amiss with the detectors or with the whales. © 2009 Discovery Channel

Keyword: Language; Hearing
Link ID: 13575 - Posted: 06.24.2010

High levels of a hormone that controls appetite appear to be linked to a reduced risk of developing Alzheimer's disease, US research suggests. The 12-year-study of 200 volunteers found those with the lowest levels of leptin were more likely to develop the disease than those with the highest. The JAMA study builds on work that links low leptin levels to the brain plaques found in Alzheimer's patients. The hope is leptin could eventually be used as both a marker and a treatment. The hormone leptin is produced by fat cells and tells the brain that the body is full and so reduces appetite. It has long been touted as a potential weapon in treating obesity. But there is growing evidence that the hormone also benefits brain function. Research on mice - conducted to establish why obese patients with diabetes often have long-term memory problems - found those who received doses of leptin were far more adept at negotiating their way through a maze. The latest research, carried out at Boston University Medical Center, involved regular brain scans on 198 older volunteers over a 12-year period. A quarter of those with the lowest levels of leptin went on to develop Alzheimer's disease, compared with 6% of those with the highest levels. BBC © MMIX

Keyword: Alzheimers; Hormones & Behavior
Link ID: 13574 - Posted: 06.24.2010

by Peter Aldhous Since this article was first posted, the American Psychiatric Association has announced that the publication of DSM-V will be delayed until May 2013. "Extending the timeline will allow more time for public review, field trials and revisions," says APA president Alan Schatzberg. When doctors disagree with each other, they usually couch their criticisms in careful, measured language. In the past few months, however, open conflict has broken out among the upper echelons of US psychiatry. The focus of discord is a volume called the Diagnostic and Statistical Manual of Mental Disorders, or DSM, which psychiatrists turn to when diagnosing the distressed individuals who turn up at their offices seeking help. Regularly referred to as the profession's bible, the DSM is in the midst of a major rewrite, and feelings are running high. Two eminent retired psychiatrists are warning that the revision process is fatally flawed. They say the new manual, to be known as DSM-V, will extend definitions of mental illnesses so broadly that tens of millions of people will be given unnecessary and risky drugs. Leaders of the American Psychiatric Association (APA), which publishes the manual, have shot back, accusing the pair of being motivated by their own financial interests - a charge they deny. The row is set to come to a head next month when the proposed changes will be published online. For a profession that exists to soothe human troubles, it's incendiary stuff. © Copyright Reed Business Information Ltd.

Keyword: Schizophrenia; Depression
Link ID: 13573 - Posted: 06.24.2010

Post menopausal women who take anti-depressants face a small - but statistically significant - increased risk of a stroke, research suggests. The US study was based on 136,293 women aged 50 to 79, who were followed for an average of six years. Anti-depressant users were 45% more likely to have a stroke than women not taking the drugs. The data, published in Archives of Internal Medicine, is taken from the Women's Health Initiative Study. When overall death rates were examined, those on anti-depressants were found to have a 32% higher risk of death from all causes during the study than non-users. The researchers stressed that the overall risk of a stroke was relatively small. Even for women on anti-depressants, it was less than one in 200 chance in any given year. However, they said that because so many women were taking anti-depressants the effect would be significant across the entire population. It is not clear whether taking anti-depressants is solely responsible for the increased risk of a stroke. Depression itself is known to be a risk factor for cardiovascular problems. BBC © MMIX

Keyword: Depression; Stroke
Link ID: 13572 - Posted: 06.24.2010

by Andy Coghlan Octopuses have been observed carrying coconut shells in what researchers claim is the first recorded example of tool use in invertebrates. There is a growing record of tool use in animals and birds, from musical "instruments" made by orang-utansMovie Camera to sponges used by dolphins to dislodge prey from sand. Now veined octopuses, Amphioctopus marginatus, have been filmed picking up coconut halves from the seabed to use as hiding places when they feel threatened. "This octopus behaviour was totally unexpected," says Julian Finn, a marine biologist at Museum Victoria in Melbourne, Australia, who has filmed at least four individual veined octopuses performing the trick off the coast of Indonesia. Discarded coconuts People living in Indonesian coastal villages discard coconut shells into the sea after use. When the octopuses come across these on the seabed, they drape their bodies over and around the shells, hollow-side up, leaving their eight arms dangling over the edges. The octopuses then lift the shells by making their arms rigid, before tiptoeing away in a manoeuvre Finn calls stilt-walking. © Copyright Reed Business Information Ltd

Keyword: Intelligence; Evolution
Link ID: 13571 - Posted: 06.24.2010

By Rachel Saslow Two mice. One weighs 20 grams and has brown fur. The other is a hefty 60 grams with yellow fur and is prone to diabetes and cancer. They're identical twins, with identical DNA. It turns out that their varying traits are controlled by a mediator between nature and nurture known as epigenetics. A group of molecules that sit atop our DNA, the epigenome (which means "above the genome") tells genes when to turn on and off. Duke University's Randy Jirtle made one of the mice brown and one yellow by altering their epigenetics in utero through diet. The mother of the brown, thin mouse was given a dietary supplement of folic acid, vitamin B12 and other nutrients while pregnant, and the mother of the obese mouse was not. (Though the mice had different mothers, they're genetically identical as a result of inbreeding.) The supplement "turned off" the agouti gene, which gives mice yellow coats and insatiable appetites. "If you look at these animals and realize they're genetically identical but at 100 days old some of them are yellow, obese and have diabetes and you don't appreciate the importance of epigenetics in disease, there's frankly no hope for you," Jirtle says. He offers this analogy: The genome is a computer's hardware, and the epigenome is the software that tells it what to do. Epigenomes vary greatly among species, Jirtle explains, so we cannot assume that obesity in humans is preventable with prenatal vitamins. But his experiment is part of a growing body of research that has some scientists rethinking humans' genetic destinies. Is our hereditary fate -- bipolar disorder or cancer at age 70, for example -- sealed upon the formation of our double helices, or are there things we can do to change it? Are we recipients of our DNA, or caretakers of it? © 2009 The Washington Post Company

Keyword: Genes & Behavior
Link ID: 13570 - Posted: 06.24.2010

By Katherine Ellison Gulf War veteran Lynn Gibbons has awful memories of combat with her fourth-grade son, Brent. "He was an out-of-control monster whenever you asked him to do something," the former Air Force computer operations officer recalls. Brent, who had received a diagnosis of attention-deficit hyperactivity disorder, was also flailing in his classes at Saratoga Elementary School in Springfield -- unable, says his mom, to write a coherent paragraph. That was seven years ago. Today Brent is taking advanced-placement high school courses, maintaining a 3.5 grade-point average, playing guitar in a band and -- drum roll -- helping with chores. Says Gibbons: "I am no longer afraid that jail time will be in his future." What made the difference, she's convinced, is a high-tech intervention called neurofeedback, also known as EEG biofeedback. Ordinary biofeedback is a kind of mind-over-body training in which a person uses electronic equipment to monitor an involuntary physiological process such as heart rate and learns to gain some control over it. Neurofeedback operates on the same principle -- except in this case, it's mind over brain. Proponents claim neurofeedback can help alleviate a broad range of problems, including not only ADHD but anxiety, depression, autism and brain injuries. Yet the costly, time-consuming therapy has long been dogged by skeptics who call it a placebo at best, a rip-off at worst. © 2009 The Washington Post Company

Keyword: ADHD; Attention
Link ID: 13569 - Posted: 06.24.2010

Ewen Callaway, reporter People with autism, conventional wisdom goes, have trouble reading the emotions of others. However, brain scans suggest they also have difficulties getting in touch with their inner selves. In a study published yesterday in the journal Brain, Michael Lombardo at the University of Cambridge reports scanning the brains of 66 males - half with autism spectrum disorder (ASD), half developmentally normal - while they thought and made judgements about themselves and, separately, Queen Elizabeth. For the non-autistic subjects, two brain areas linked to self-reflection proved more active when they thought about themselves, compared with thinking about the queen. Not so for those with ASD. One region, the ventralmedial prefrontal cortex, tended to respond similarly to regal and personal judgements, while the second region, the middle cingulate cortex, proved more active when ASD patients thought about the queen. These neurological differences correlated with social ability. According to Lombardo's team: "Individuals whose ventromedial prefrontal cortex made the largest distinction between mentalising about self and other were least socially impaired in early childhood, while those whose ventromedial prefrontal cortex made little to no distinction between mentalising about self and other were the most socially impaired in early childhood." © Copyright Reed Business Information Ltd.

Keyword: Autism; Emotions
Link ID: 13568 - Posted: 06.24.2010

By C. CLAIBORNE RAY Q. A family member has been unable to leave the house because of severe vertigo caused by something that sounds like cochlea hydrox. What is it and what might help? A. The disorder is called cochlear hydrops, and it also involves hearing problems. Sometimes called atypical Ménière’s disease, it is caused by abnormally high fluid pressure in the part of the inner ear called the cochlea, which is involved in both balance and hearing. Pressure surges bombard the sensitive nerve endings that normally transmit information about the body’s position to the brain. Besides causing bouts of vertigo to the point of nausea and hearing problems, cochlear hydrops leads to a sense of fullness in the ear and ringing, or tinnitus, often described as a low-pitched roar. These symptoms sometime precede full-blown vertigo. The cause is not always easy to identify, and other disorders, like thyroid problems and even inflammatory infections like syphilis, should be explored. The problem can be associated with autoimmune disorders like lupus; with hormonal surges, especially in women, who make up somewhat more than half the sufferers; and with allergic attacks. Dietary changes often help avert attacks of vertigo, especially the avoidance of foods identified as triggers and substances like caffeine. A low-salt diet and diuretics can also help control the fluid pressure. Anti-inflammatory drugs like steroids are usually helpful. Copyright 2009 The New York Times Company

Keyword: Hearing
Link ID: 13567 - Posted: 06.24.2010

By Naomi Kenner and Russell Poldrack Are you a media multitasker? We know you're reading a blog, but what else are you doing right now? Take a quick inventory: Are you also listening to music? Monitoring the progress of a sports game on TV? Emailing your co-worker? Texting your friend? On hold with tech support? If your inventory has revealed a multitasking lifestyle, you are not alone. Media multitasking is increasingly common, to the extent that some have dubbed today’s teens "Generation M." People often think of the ability to multitask as a positive attribute, to the degree that they will proudly tout their ability to multitask. Likewise it’s not uncommon to see job advertisements that place “ability to multitask” at the top of their list of required abilities. Technologies such as smartphones cater to this idea that we can (and should) maximize our efficiency by getting things done in parallel with each other. Why aren’t you paying your bills and checking traffic while you’re driving and talking on the phone with your mother? However, new research by EyalOphir, Clifford Nass, and Anthony D. Wagner at Stanford University suggests that people who multitask suffer from a problem: weaker self-control ability. The researchers asked hundreds of college students fill out a survey on their use of 12 different types of media. Students reported not only the number of hours per week that they used each type of media, but also rated how often they used each type of media simultaneously with each other type of media. The researchers created a score for each person that reflected how much their lifestyle incorporated media-multitasking. © 1996-2009 Scientific American Inc.

Keyword: Attention
Link ID: 13566 - Posted: 06.24.2010

By Olga Kuchment Imagine planning your schedule for the week and seeing the days on the calendar appear before you as a spiral staircase so real you feel like you could touch it. That's what it's like to have spatial-sequence synesthesia, a condition in which people perceive numbered sequences as visual patterns. Now researchers have shown that individuals with the condition have superior memories, recalling dates and historic events much better than can the average person. Spatial-sequence synesthesia is one of several types of synesthesia, neural conditions in which senses combine in unusual ways. Grapheme-color synesthetes, for example, associate letters and numbers with colors; the number six might always look red to them. In other types of synesthesia, the word "cat" may create the taste of tomato soup, or the sound of a flute may appear as a blue cloud. Recently, scientists have wondered if synesthesia--especially spatial-sequence synesthesia--might be linked to a superior ability to form memories. So psychologist Julia Simner of the University of Edinburgh in the United Kingdom tested for unusual mnemonic skills or other mental talents in 10 spatial-sequence synesthetes. Subjects had to quickly recall the dates of 120 public events occurring between 1950 and 2008, such as the year Nelson Mandela was freed from jail in South Africa (1990) or the year My Fair Lady won the Academy Award for best picture (1965). On average, non-synesthetic volunteers were off by about 8 years for each date, but the synesthetes were wrong by only about 4 years. They could also name almost twice as many events from specified years in their own lives than could the controls. "They have this subtle extra gift," says Simner. © 2009 American Association for the Advancement of Science.

Keyword: Learning & Memory
Link ID: 13565 - Posted: 06.24.2010

People who plan to drink at parties could designate a driver or stop drinking early enough to allow their blood-alcohol levels to go down before getting behind the wheel. Drinking a cup of coffee for every cup of spiked eggnog likely won't help you drive home more safety, a study on drunken mice suggests. "It debunks the myth that you can sober somebody up with coffee," said study author Thomas Gould, a professor of psychology at Temple University in Philadelphia. Gould and his colleagues observed mice that had been given ethanol, caffeine, a combination of the two, or neither, as the rodents learned to navigate a maze in the shape of a plus sign. In one of the arms of the maze, lights went on and sound was emitted from a speaker. Since mice don't like bright, loud areas, they normally learned to avoid that area. But animals given alcohol didn't learn to avoid the unpleasant environment and didn't remember that it was dangerous, Gould's team reported in the current issue of the journal Behavioural Neuroscience, published by the American Psychological Association. "One of my colleagues says, 'You know, if you give someone who's drunk a coffee, all you're making is a wide-awake drunk,' and this kind of supports that," Gould told CBC Radio's As It Happens. © CBC 2009

Keyword: Drug Abuse
Link ID: 13564 - Posted: 06.24.2010

By Bina Venkataraman Not all foods are created equal, whether the goal is having a healthier heart or losing weight. And the same could be true when it comes to what we eat and how depressed or happy we feel, how well we learn, and whether we suffer from mental illness. A study published last month in the Archives of Internal Medicine divided a group of 106 overweight and obese people into two groups: About half spent a year following a diet low in fat - say goodbye to steak and pastries - and high in carbohydrates (breads, pastas, beans, potatoes, and rice). The other half went for a year on a low-carb, high-fat diet - have a burger, but skip the bun. In both groups, people lost an average of 30 pounds each and generally said they felt happier two months into the diet. But after a year on the diet, the people who ate less fat and more carbs continued to report feeling happier and less depressed and anxious than they had before. The other dieters, who ate more fat and less carbohydrates, felt their moods decline from the early rise they had noted. One reason for the difference, the researchers argued, might be that eating more carbohydrates than fat and protein pumps up the production in the brain of serotonin, a chemical that has been linked with improved mood and mental health. “There’s tremendous interest in how nutrition is related to brain function,’’ said Dr. Perry Renshaw, who currently is a psychiatry professor at the University of Utah School of Medicine. Renshaw is studying whether creatine - a chemical found in fish, meat, and eggs - helps women respond more quickly to antidepressants known as SSRIs (selective serotonin reuptake inhibitors). Examples of SSRIs include Prozac and Zoloft. “It does seem there are natural products that have effects on mood.’’ © 2009 NY Times Co

Keyword: Depression; Obesity
Link ID: 13563 - Posted: 06.24.2010

By Jennifer Ouellette From the annals of "How did I miss that story?": While reading a news snippet about how scientists hope to mimic the structure of a mantis shrimp's eyes to improve on the next generation of Blu-Ray players, I stumbled on the fact that there is an X-ray space telescope under development using technology based on lobster vision. It's called the Lobster All-Sky X-Ray Monitor (LASXM), and according to Nigel Bannister of the University of Leicester, the telescope would be "ideal for use as an all-sky X-ray monitor" because of its unlimited field of view." It's not a new idea: in fact, it was first proposed in the 1970s by a scientist at the University of Arizona named Roger Angel, but it's taken 30 years for optics to advance to the point where building such a technology is even possible. What makes lobsters special? Well, they have these pea-sized compound eyes made up of long, narrow square cells that give the creature a 180-degree field of view. This allows for maximum reflectivity; each cell captures a tiny amount of light, but the light enters the eye from many different angles and only then is the light focused into a single image. Lobsters don't have great image resolution, but they don't really need it. What they do have is ultra-sensitivity to detect movement, and even the polarization of light. LASXM would mimic that structure with a new technology called microchannel plates: six nested modules -- each a bundle of 3 million parallel glass channels -- that would combine to give the instrument that same 180-degree field of view. Put it orbit around the Earth aboard a satellite or the International Space Station, such that it completes its orbit every 90 minutes, and you would quickly compile a complete x-ray picture of the sky. © 2009 Discovery Communications, LLC

Keyword: Vision; Evolution
Link ID: 13562 - Posted: 06.24.2010