by Sara Reardon The carnival trick of guessing a person's age has just gained a lot more rigour. A new brain imaging technique can predict a child's age to within a year. The technique could be useful for determining whether a child is developing normally, or confirm that a young person is the age they say they are. There is no doubt that children of the same age often have vast differences in their maturity and mental ability, says Timothy Brown of the University of California in San Diego. But what hasn't been clear is how much of that difference is psychological and how much is biological. To simplify the question, Brown and his colleagues looked at brain structure rather than brain activity. Working with 10 hospitals in different parts of the US, they recruited 885 children and young adults between the ages of 3 and 20. They ensured that the participants represented many different races, socioeconomic statuses and education levels. The group performed structural magnetic resonance imaging (MRI) on the young peoples' brains. The images showed features such as the size of each brain region, the level of connectivity between neurons, and how much white matter was insulating the neurons. By putting all these features together in an algorithm, the researchers formed a picture of what the average brain looks like at each year of childhood. Different areas and features of the brain varied between individuals, but the algorithm correctly predicted a child's age to within a year in 92 per cent of cases. © Copyright Reed Business Information Ltd.

Keyword: Development of the Brain; Brain imaging
Link ID: 17181 - Posted: 08.18.2012

By Jason G. Goldman The largest fish in the ocean is the whale shark (Rhincodon typus). This massive, migratory fish can grow up to twelve meters in length, but its enormous mouth is designed to eat the smallest of critters: plankton. While the biggest, the whale shark isn’t the only gigantic filter-feeding shark out there: the basking shark and the megamouth shark also sieve enormous amounts of the tiny organisms from the sea in order to survive. While scientists like Al Dove and Craig McClain (of Deep Sea News) are learning more and more about the basic biology and behavior of these magnificent creatures, other scientists are busy investigating their neuroanatomy. A few years ago, Kara E. Yopak and Lawrence R. Frank from the University of California in San Diego got their hands on two whale shark brains from an aquarium, and put them into an MRI scanner. But they weren’t just interested in imaging the brains of the whale sharks. What they wanted to know was how the organization of whale shark brains compared to the brains of other shark species for which scientists had previously obtained neuroanatomical data. Would the brains of two species be more similar if they shared a recent evolutionary ancestor, and were therefore more genetically related? Or would shark brains be more similar among species that shared a similar lifestyle, such as those that patrol the middle and surface of the water column (pelagic sharks, such as the great white, oceanic whitetip, blue, mako, and whale sharks) versus those that live along the sea floor (benthic sharks, such as the nurse and cat sharks). Or perhaps the brains of sharks would be grouped according to their habitat, such as those that live in coastal waters, around reefs, or in the open ocean. Maybe sharks brains ought to be grouped according to behavioral specialization, such as hunting methods. Answers to these questions could shed some important light on brain evolution, both in sharks as well as more generally. © 2012 Scientific American

Keyword: Evolution; Brain imaging
Link ID: 17180 - Posted: 08.18.2012

Sandrine Ceurstemont, Most of us would probably find it difficult to remember everything we did yesterday. But for a small group of people with near-perfect memory, autobiographical events from decades ago can be recalled just as easily as scrolling through a DVD. Sean Conlon, a food and beverages director from Baltimore, Maryland, and Frank Healy, a counsellor based in Pennsylvania, are two of about 30 people now confirmed to possess highly superior autobiographical memory. In this video, you can watch them recall life events from specific dates without prior preparation. Since the dates coincide with historical events, we were able to check that they weren't making it up. The two men recently had their brain scanned by memory researcher James McGaugh and colleagues from the University of California, Irvine, whose work is now revealing differences in certain memory regions for people with the ability. The team also found that super-memorisers share some of the hallmarks of obsessive compulsive disorder (OCD). Conlon claims that he doesn't have obsessive tendencies, other than being preoccupied with his past. Healy, however, admits that he's quite germ-phobic: at restaurants he will go and wash his hands as soon as he places his order. Both men have found their memory to be advantageous in their jobs. "It helps me if I have a client who stops therapy for a year or two and then returns," says Healy. "I'm instantly able to remember their birthday, their issues and everything about them." © Copyright Reed Business Information Ltd.

Keyword: Learning & Memory; OCD - Obsessive Compulsive Disorder
Link ID: 17179 - Posted: 08.18.2012

By Bruce Bower A callous, manipulative psychopath convicted of a brutal crime can count on a long prison stint. But a judge may issue a slightly shorter sentence if presented with a biological explanation for the criminal’s psychopathic personality. Supplying judges with scientific evidence about suspected brain deficits in psychopathy led to a reduction in prison sentences from about 14 years to 13 years, researchers report in the Aug. 17 Science. The results come from a nationwide, online survey of state judges given a hypothetical scenario about a psychopath convicted of what lawyers call aggravated battery. Judges taking the survey tended to view psychopathic criminals as dangerous, whether or not scientific evidence was introduced, say psychologist Lisa Aspinwall, lawyer Teneille Brown and philosopher James Tabery, all of the University of Utah in Salt Lake City. A hypothetical psychopath in the new study got sent to the slammer for longer than the average nine-year sentence given to non-psychopaths found guilty of aggravated battery in real courts. Aspinwall and her colleagues informed judges that clinicians use psychopathy — which is not an official psychiatric diagnosis — to refer to individuals who are impulsive, emotionally shallow, outwardly charming, lacking in empathy or remorse, chronic liars and callous manipulators (SN: 12/9/06, p. 379). Judges were told that psychopathy is incurable. © Society for Science & the Public 2000 - 2012

Keyword: Aggression
Link ID: 17178 - Posted: 08.18.2012

by Michael Marshall Big and strong predators are dangerous enough, but clever ones are the worst. There's nothing more annoying than realising you've been outwitted in the seconds before you're disembowelled. Killer whales are some of the smartest predators on Earth. They can climb onto beaches to catch sea lions, stun fish by slapping them with their tails, and create waves to knock seals off ice floes. That might be because they learn from each other. They are one of the few animals that can imitate behaviours that they haven't seen before, and they are ferociously quick students. Despite their name, killer whales are actually dolphins – albeit rather large ones. Populations in different areas are quite dissimilar, and genetic evidence suggests that there are actually several species. A key difference between populations is that they target different prey, using different techniques. In the Crozet Islands in the Indian Ocean, whales strand themselves on beaches to hunt southern elephant seals. In Patagonia, they hunt sea lions in the same way. Beaching oneself on purpose is unusual, and it takes young killer whales years to get the hang of it. Even at five or six years old, they often need their mothers' help to get back off the beach. © Copyright Reed Business Information Ltd.

Keyword: Learning & Memory; Aggression
Link ID: 17177 - Posted: 08.18.2012

By Linda Carroll Scientists have long assumed that fading memories are just a normal part of aging. But a new study suggests that certain 80-somethings can remember every bit as well as people much younger. Researchers from Northwestern University found that these mentally sharp octogenarians, dubbed SuperAgers, also have brains that look very much like those of people in middle-age, according to the study published in the Journal of International Neuropsychological Society. For the new study, researchers used MRIs to look at the thickness of the outer layer of the brain, a region called the cortex, in SuperAgers, normally aging 80-somethings, and healthy 50- to 65-year-olds. What they found was intriguing – the SuperAgers had brains that looked very much like those of the younger people in the study and in some ways looked even healthier. "We were very surprised at that," says study co-author Emily Rogalski, an assistant research professor at the cognitive neurology and Alzheimer's disease center at the Northwestern University Feinberg School of Medicine "When we looked at cortical thickness, we were very shocked to see that even with a 20- to 30-year age gap, there was seemingly no difference in the cortical thickness," she says. "In normally aging 80-year-olds, you see quite a bit of cortical thinning, even among those who are still performing normally for their age." © 2012 NBCNews.com

Keyword: Alzheimers
Link ID: 17176 - Posted: 08.18.2012

by Jessica Hamzelou COULD we stem the tide of ageing by delaying the deterioration of stem cells? A new compound that appears to do just that could help us find ways to protect our organs from age-related wear and tear, experiments in mice suggest. As we age, so do our mesenchymal stem cells (MSCs): their numbers in our bone marrow decline, and those that are left lose the ability to differentiate into the distinct cell types - such as bone, cartilage, fat and possibly muscle cells - that help in the healing process. "We think this ageing of stem cells may be linked to the onset of some age-related disorders, such as osteoporosis," says Ilaria Bellantuono at the University of Sheffield in the UK. Earlier research in mice had suggested that the prion protein expressed by MSCs might play a role in holding back stem cell ageing. Mice lacking the prion protein were less able to regenerate blood cells. The study provided more evidence that correctly folded prions serve a useful purpose in the body, despite the role that misfolded prions play in BSE and vCJD. Bellantuono and her colleagues have now found that the prion protein performs a similar function in humans - older MSCs from human bone marrow expressed less of the protein than younger ones. In a bid to find a compound that might slow MSC ageing, the team tested numerous molecules known to target prion proteins on dishes of human stem cells. One molecule emerged as a potential candidate - stem cells treated with it produced 300 times the number of cells over 250 days than untreated stem cells. The treated cells kept on dividing for longer. © Copyright Reed Business Information Ltd.

Keyword: Prions; Stem Cells
Link ID: 17175 - Posted: 08.18.2012

by Molly Docherty The brain drain is real. There is a network of previously unrecognised vessels that rid the brain of unwanted extracellular fluids and other substances, including amyloid-beta – a peptide that accumulates in the brain of people with Alzheimer's. The new discovery looks set to add to our understanding of the disease. Jeffrey Iliff at the University of Rochester Medical Center, New York, and his colleagues, were intrigued by the fact that there are no obvious lymphatic vessels in the brain. Among other things, the lymphatic system removes waste interstitial fluids from body tissue. "It seemed strange that such an important and active organ wouldn't have a specialised waste-removal system," says Iliff. When the researchers added fluorescent and radioactive tracers to the cerebrospinal fluid of live mice, the tracers quickly spread throughout the rodents' brains. Using two-photon microscopy to visualise the movement in real-time, the team saw cerebrospinal fluid permeating the entire brain through 'pipes' surrounding blood vessels, similar to the lymphatic system that services all other organs. The pipes work on hydraulic principles, though, and so the system breaks upon opening, making it hard to identify it outside living organisms. © Copyright Reed Business Information Ltd.

Keyword: Brain imaging
Link ID: 17174 - Posted: 08.16.2012

by Jessica Hamzelou When something goes wrong in your brain, you'd think it would be a good idea to get rid of the problem. Turns out, sometimes it's best to keep hold of it. By preventing faulty proteins from being destroyed, researchers have delayed the symptoms of a degenerative brain disorder. SNAP25 is one of three proteins that together make up a complex called SNARE, which plays a vital role in allowing neurons to communicate with each other. In order to work properly, all the proteins must be folded in a specific way. CSP alpha is one of the key proteins that ensures SNAP25 is correctly folded. Cells have a backup system to deal with any misfolded proteins – they are destroyed by a bell-shaped enzyme called a proteasome, which pulls the proteins inside itself and breaks them down. People with a genetic mutation that affects the CSP alpha protein – and its ability to correctly fold SNAP25 – can develop a rare brain disorder called neuronal ceroid lipofuscinosis (NCL). The disorder causes significant damage to neurons – people affected gradually lose their cognitive abilities and struggle to move normally. To find out what role proteasomes might play in NCL, Manu Sharma and his colleagues at Stanford University in California blocked the enzyme in mice that were bred to lack CSP alpha. "We weren't sure what would happen," says Sharma. Either the misfolded SNAP25 would accumulate and harm the cells, or some of the misfolded proteins may work well enough to retain some of their function. © Copyright Reed Business Information Ltd.

Keyword: Movement Disorders; Genes & Behavior
Link ID: 17173 - Posted: 08.16.2012

by Emily Underwood In the Hans Christian Andersen tale "The Nightingale," a songbird melts an emperor's heart with its singing, but flies away when the ruler forces it to sing duets with a jeweled, mechanical bird that warbles only waltzes. There's a moral here, a new study suggests. Although humans have long attributed musical qualities to birdsong, cold, hard statistics show that's all an illusion. The birds we prize most for their songs sound most like the human voice, says Robert Zatorre, a cognitive neuroscientist at McGill University in Montreal, Canada, who was not involved in the study. The sounds they make have clear tones, repeat similar phrases, and are made of discrete notes. Despite these pleasing attributes, however, it has never been scientifically proven that the notes in birdsong follow the same organizational rules that govern most musical compositions. In fact, says ecologist Marcelo Araya-Salas of New Mexico State University in Las Cruces, author of the new study, no one has ever addressed the question using quantitative methods. Billions of potential notes exist between the low and high notes in an octave. But for reasons that researchers only partially understand—the physiological limits of human hearing, for example, and cultural preferences that have evolved over time—most music is based on variations of only five to 12 notes. A baby grand piano, which has 88 keys, is tuned so that each octave is divided into twelve equal intervals, called half-steps, that form the 12-note chromatic scale underlying most of Western music. The seven-note diatonic scale, "do, re, mi, fa, so, la, ti (do)," is another familiar example, as is the ancient five-note, pentatonic scale used in Greek lyre music and nearly every riff played on the electric guitar. © 2010 American Association for the Advancement of Science

Keyword: Animal Communication; Language
Link ID: 17172 - Posted: 08.16.2012

By Scicurious Or not. I so want to like press releases. But I got this press release: “SCIENTISTS CAN NOW BLOCK HEROIN, MORPHINE ADDICTION” And I got the paper along with it. As I read the paper, my head slowly hit the desk. And hit it again, and again, as I compared the press release to the paper and prepared to write this post. I will have a lovely little round bruise now. But let’s get the big questions out of the way first: 1. Is this paper good? Oh yes! Really neat! Cool new mechanism! 2. Does it “block” heroin addiction? No. This press release hurts us precious. It hurts us. This paper has a lot of GREAT things about it, and there’s a lot of potential for the future with a new mechanism for drug action, especially in the area of pain relief (which sadly got short shrift in the press release). But no one has cured addiction yet. © 2012 Scientific American

Keyword: Drug Abuse; Pain & Touch
Link ID: 17171 - Posted: 08.16.2012

Sleep apnea, a disorder characterized by snoring and daytime sleepiness that has been linked to cardiovascular disease, has primarily been viewed as a male problem, but a new Swedish study suggests the sleep disorder is also a common problem among women. Dr. Karl A Franklin of Umea University Hospital in Sweden and colleagues noted in the study released Wednesday that there have been only a few epidemiological studies conducted in women, and the frequency of the disorder in women "is still uncertain." Obstructive sleep apnea, in which a person has short pauses in breathing during sleep, may be caused by a temporary collapse of the airway. The gaps in breathing can last 10 to 30 seconds, and may occur dozens or hundreds of times each night. For their study, Franklin and the other Swedish researchers investigated 400 women from a population-based random sample of 10,000 women aged 20 to 70. The women answered a questionnaire and were monitored overnight. Obstructive sleep apnea was found in 50 per cent of the women subjects, with 14 per cent of them having a severe form of the disorder. Treatment for obstructive sleep apnea: For mild to moderate apnea, the best treatment is continuous positive airway pressure (CPAP). © CBC 2012

Keyword: Sleep
Link ID: 17170 - Posted: 08.16.2012

by Catherine de Lange A potential new treatment to prevent morphine addiction is at hand. Researchers have identified an immune receptor involved in addiction to the drug, and found a way to block this receptor without affecting pain relief. The discovery offers hope that morphine can be used to relieve pain without running the risk of addiction. Opioid drugs such as morphine are known to target opioid receptors in the central nervous system, which block pain signals to the brain and flood it with the "feel-good" chemical dopamine. This reward response is what makes opioids so addictive. Morphine is a widely used pain killer, but its addictiveness means it has to be administered with caution, and often cannot be used for protracted periods of chronic pain. Mark Hutchinson from the University of Adelaide, Australia, and colleagues have now discovered that as well as working through the central nervous system, opioid drugs like heroin and morphine trigger an immune response, which seems to boost their addictive effects. Blocking this immune response in animals inhibits their addiction. Hutchinson's team previously observed that opioids bind to TLR-4 – immune system receptors in the cell membrane – which are responsible for identifying foreign bodies. However, the team did not know how this binding affected the body. © Copyright Reed Business Information Ltd.

Keyword: Pain & Touch; Drug Abuse
Link ID: 17169 - Posted: 08.15.2012

By Kathleen Raven A compound already sitting on the shelves of biomedical laboratories and emergency room supply closets seems to interrupt the formation of neurodegenerative protein clumps found in Huntington’s disease, according to a preliminary animal study published August 7 in the Journal of Neuroscience. This versatile agent, called methylene blue, gets a mention in medical literature as early as 1897 and was used to treat, at one time or another, ailments ranging from malaria to cyanide poisoning. The U.S. Food and Drug Administration has never formally approved it as a therapy for any illnesses. But that fact hasn’t stopped biomedical researchers from tinkering with the agent’s apparent ability to improve cognitive function. And although the new paper out today relies on a Huntington’s disease model in flies and mice, scientists are hopeful. "Because of existing knowledge of methylene blue and the fact that it’s not harmful to humans, I would hope that progress toward clinical trials could go relatively quickly," says Leslie Thompson, a neurobiologist at University of California–Irvine and lead author on the new study. Huntington’s disease occurs when the C-A-G sequence of DNA base pairs repeat too often on the HTT gene, resulting in an abnormally long version of the huntingtin protein, that therefore folds incorrectly and forms clumps in the brain. The illness usually begins to affect people in their 30s and 40s, causing movement problems and early death. No drug is currently available to stop the disease from progressing. © 2012 Scientific American

Keyword: Huntingtons
Link ID: 17168 - Posted: 08.15.2012

by Michael Slezak A lack of anti-Müllerian hormone in boys with autistic spectrum disorder (ASD) may lead to a greater number of symptoms. Michael Pankhurst and Ian McLennan from the University of Otago in New Zealand say hormones like anti-Müllerian hormone (AMH) that control the speed at which the body and brain develop might play a central role in the way that ASD progresses through childhood. The pair analysed the level of AMH in 82 boys with ASD. The lower the level of AMH in their blood, the greater the number of autistic traits they displayed. In an earlier study, McLennan and his colleagues found that an increased level of AMH was associated with slower overall growth and development in boys. Together, he thinks the two studies suggest that a lack of AMH could cause the brain to develop too quickly, leading to an increased number of symptoms in boys with ASD. "Rapid development is associated with a greater frequency of developmental disorders," says McLennan. A complex system that develops quickly is more likely to contain errors than one that develops more slowly, he explains. Surprisingly, there was no difference between the average level of anti-Müllerian hormone in the children with ASD and 16 boys without autism. McLennan says this shows that the hormone doesn't cause ASD, but may increase the number of symptoms in people who have the condition. © Copyright Reed Business Information Ltd.

Keyword: Autism; Hormones & Behavior
Link ID: 17167 - Posted: 08.15.2012

Analysis by Jesse Emspak A glass inspired by spider's webs is being used to keep birds from smacking into windows. Birds can't see glass well, and so many of them die when they hit picture windows. Humans can't see glass well either, which might explain why some people try to walk through glass doors. But most people know that the refection of the sky and landscape in a window isn't real -- unfortunately, birds don't. According to the Fatal Light Awareness Program, a building with glass walls or windows can kill up to 10 birds per day, and estimates of worldwide deaths from such collisions reach hundreds of millions of birds each year. On Lindisfarne Island, off the northeastern coast of England, local authorities wanted to do something about it. Hundreds of species of migratory birds pass through every year. So officials decided to cover a lookout tower with glass designed by Arnold Glas, a German company. Called Ornilux, the glass has a spiderweb-like pattern that humans can't see unless they stand very close (see image below, right). But because glass reflects ultraviolet light, birds can see the pattern very well. Spider webs, particularly those of orb weaver spiders, work the same way, reflecting UV and alerting the bird that there is something there. While flying through a web wouldn't hurt a bird, the bird doesn't know that. So they avoid them. The glass was tested in a flight tunnel in the United States. Birds were allowed to fly to one end of the tunnel which was covered with two types of glass, one with the UV-reflective coating. The birds avoided hitting the coated glass up to 68 percent of the time. © 2012 Discovery Communications, LLC.

Keyword: Vision
Link ID: 17166 - Posted: 08.15.2012

By Susan Milius COLLEGE PARK, Md. — A mantis shrimp, which has one of the most elaborate visual systems ever discovered, turns out to be pretty lousy at distinguishing one color from another. The puzzling underachievement may mean that the mantis shrimp brain perceives color in a way new to science, says Hanne Thoen of the University of Queensland in Brisbane, Australia. She presented results from her ongoing study August 6 at the 10th International Congress of Neuroethology. The stalked eyes of mantis shrimp species that live in shallow water can have up to 16 kinds of photoreceptor cells, 12 of which are specialized for different colors. People make do with four kinds, three of which pick up colors. Yet tests with pairs of increasingly similar colors found that the mantis shrimp Haptosquilla trispinosa flunks out when choices narrow to colors 15 nanometers apart in wavelength, Thoen said. At sweet spots in the color spectrum, people can distinguish between colors only 1 or 2 nanometers apart. “Hanne’s results are a bit of a shock to us,” says Thomas Cronin of the University of Maryland, Baltimore County, whose lab also studies mantis shrimp vision. Thoen tested the color vision of mantis shrimp by training them to scoot out of their burrows toward a pair of optical fibers and punch at the one glowing a particular color. As she narrowed the color gap between the two fibers, she could tell when the animals no longer discerned a difference. © Society for Science & the Public 2000 - 2012

Keyword: Vision; Evolution
Link ID: 17165 - Posted: 08.15.2012

By Michelle Andrews, Alzheimer’s disease can’t be prevented or cured, and it ranks second only to cancer among diseases that people fear. Still, in an international study last year from the Harvard School of Public Health, about two-thirds of respondents from the United States said they would want to know if they were destined to get the disease. Although there are no definitive tests that predict whether most people will get the disease, people sometimes want such information for legal and financial planning purposes or to help weigh the need for long-term-care insurance. Current tests to identify the risk of developing Alzheimer’s disease when no symptoms are present provide only limited information, and health insurance generally doesn’t cover them. But that’s not stopping some people from trying to learn more. Most of the 5 million people who have Alzheimer’s developed it after age 60. In these cases, the disease is likely caused by a combination of genetic, lifestyle and environmental factors. About 5 percent of Alzheimer’s patients have inherited an early-onset form that is generally linked to a mutation on one of three chromosomes. Research suggests that the brain may show signs of Alzheimer’s decades before obvious symptoms appear. Scans can identify the presence of beta-amyloid, a protein that is often deposited in the brains of people with the disease, for example. Changes in proteins in the blood or cerebrospinal fluid may also be associated with Alzheimer’s disease. © 1996-2012 The Washington Post

Keyword: Alzheimers
Link ID: 17164 - Posted: 08.14.2012

By ABBY ELLIN After downing 70 chicken wings in about an hour, Andrew Walen realized he had a problem. Oh, he had known something was wrong over the years. Normal people don’t consume 4,500 calories worth of food in one sitting, or order takeout for four when dining alone. But it took a maniacal feeding frenzy for him to finally accept the reality: He was a binge eater, and he had absolutely no control around food. “Ultimately, it was about numbing out and self-loathing,” said Mr. Walen, now 39 and a therapist in Columbia, Md. “There was this voice in my head that said, ‘You’re no good, worthless,’ and I turned to food.” Mr. Walen is one of an estimated eight million men and women in the United States who struggle with binge eating, defined as consuming large amounts of food within a two-hour period at least twice a week without purging, accompanied by a sense of being out of control. While about 10 percent of patients with anorexia and bulimia are men, binge eating is a problem shared almost equally by both sexes. A study published online in October and then in the March issue of The International Journal of Eating Disorders found that among 46,351 men and women ages 18 to 65, about 11 percent of women and 7.5 percent of men acknowledged some degree of binge eating. “Binge eating among men is associated with significant levels of emotional distress, obesity, depression and work productivity impairment,” said Richard Bedrosian, a study author and director of behavioral health and solution development at Wellness and Prevention Inc., which works with employers and health plans. Copyright 2012 The New York Times Company

Keyword: Anorexia & Bulimia; Sexual Behavior
Link ID: 17163 - Posted: 08.14.2012

Prosthetic retina helps to restore sight in mice Geoff Brumfiel Two neuroscientists have created a prosthesis that can partially restore the sight to blind mice. The device could eventually be developed for use in humans. More than 20 million people worldwide become blind owing to the degeneration of their retina, the thin tissue at the back of the eye that turns light into a neural signal. Only one prosthesis has been approved for treatment of the condition — it consists of an array of surgically implanted electrodes that directly stimulate the optic nerve and allow patients to discern edges and letters. Patients cannot, however, recognize faces or perform many everyday tasks. Sheila Nirenberg, a physiologist at the Weill Medical College at Cornell University in New York thinks that the problem is at least partially down to coding. Even though the retina is as thin as tissue paper, it contains several layers of nerves that seem to encode light into neural signals. "The thing is, nobody knew the code," she says. Without it, Nirenberg believes that visual prostheses will never be able to create images that the brain can easily recognize. Now, she and her student, Chethan Pandarinath, have come up with a code and developed a device that uses it to restore some sight in blind mice. The duo began by injecting nerve cells in the retinas of their mice with a genetically engineered virus. The virus had been designed to insert a gene that causes the cells to produce a light-sensitive protein normally found in algae. When a beam of light was then shown into the eye, the protein triggered the nerve cells to send a signal to the brain, performing a similar function to healthy rod and cone cells. © 2012 Nature Publishing Group

Keyword: Vision; Robotics
Link ID: 17162 - Posted: 08.14.2012