Daniel H. Geschwind & Genevieve Konopka The decoding of the human and chimpanzee genomes was heralded as an opportunity to truly understand how changes in DNA resulted in the evolution of our cognitive features. However, more than a decade and much detective work later, the functional consequences of such changes have proved elusive, with a few exceptions1, 2. Now, writing in Cell, Dennis et al.3 and Charrier et al.4 describe the evolutionary history and function of the human gene SRGAP2 and provide evidence for molecular and cellular mechanisms that may link the gene's evolution with that of our brain. It was already known that SRGAP2 is involved in brain development5 and that humans have at least three similar copies of the gene, whereas non-human primates carry only one6. However, the study of duplicated, or very similar, segments of DNA is hampered by the fact that most human cells carry two sets of chromosomes (one inherited from each parent), which makes it difficult to distinguish duplicated copies from the different parental forms of the gene. To circumvent this problem, Dennis et al.3 searched for copies of SRGAP2 in the genome of a hydatidiform mole — an abnormal, non-viable human embryo that results from the fusion of a sperm with an egg that has lost its genetic material; it therefore has chromosomes derived from a single parent. The authors showed that humans carry four non-identical copies (named A–D) of SRGAP2 at different locations on chromosome 1. By comparing the genes' sequences with that of the SRGAP2 gene from the orang-utan and chimpanzee, the authors estimated that SRGAP2 was duplicated in the human lineage about 3.4 million years ago, resulting in SRGAP2A (the ancestral version that we share with other primates) and SRGAP2B. Further duplications of SRGAP2B gave rise to SRGAP2C about 2.4 million years ago and to SRGAP2D about 1 million years ago (Fig. 1a). © 2012 Nature Publishing Group

Keyword: Genes & Behavior; Evolution
Link ID: 16945 - Posted: 06.21.2012

John von Radowitz A protein needed to re-grow injured nerves in limbs has been identified, raising the prospect of new treatments. The findings, in mice, have implications for helping patients recover from peripheral nerve injuries. They also open up new pathways for investigating how to regenerate neurons in the spinal cord and brain. Peripheral nerves provide the sense of touch and drive the muscles that move the arms, legs and feet. Unlike central nervous system nerves of the spinal cord, they can regrow after being cut or crushed. But how this happens is still not well understood. Scientists conducting the new research, reported in the journal Neuron, identified a signalling protein that helps switch on the regeneration process. The molecule, called leucine zipper kinase (DLK), regulates signals that tell a nerve cell it has been injured, often communicating over distances of several feet. Mice lacking DLK were unable to regrow severed nerves. Lead researcher Professor Aaron DiAntonio, from Washington University in St Louis, US, said: "DLK is a key molecule linking an injury to the nerve's response to that injury, allowing the nerve to regenerate. © independent.co.uk

Keyword: Regeneration; Trophic Factors
Link ID: 16944 - Posted: 06.21.2012

Ewen Callaway Ten years ago, psychiatrist David Skuse met a smart, cheery five-year-old boy whose mother was worried because her son had trouble following conversations with other kids at school. He struggled to remember names and often couldn’t summon the words for simple things such as toothpaste. Skuse is an expert on language development at the Institute of Child Health at University College London, but he had never encountered anything like the boy’s condition. His scientific curiosity was piqued when the mother, who is bilingual, mentioned her own difficulties remembering words in English, her native tongue. Her mother, too, had trouble recounting what had happened in television shows she had just seen. “The family history of this word-finding problem needs further investigation,” Skuse noted at the time. About half the members of this family, dubbed JR, share similar language deficits and brain abnormalities. These deficits seem to be inherited across at least four generations, Skuse and his colleagues report today in Proceedings of the Royal Society B1. Identifying the genetic basis of the family’s unique trait — which they call the ‘family problem’ — could help to explain how our brains link words to objects, concepts and ideas. “It’s like that tip-of-the-tongue moment; you’re struggling to find a word,” says Josie Briscoe, a cognitive psychologist at the University of Bristol, UK, and a study co-author. The researchers tested eight JR family members on a number of language and memory tasks to better understand their deficits. © 2012 Nature Publishing Group,

Keyword: Language; Genes & Behavior
Link ID: 16943 - Posted: 06.20.2012

by Moheb Costandi Researchers have yet to understand how genes influence intelligence, but a new study takes a step in that direction. An international team of scientists has identified a network of genes that may boost performance on IQ tests by building and insulating connections in the brain. Intelligence runs in families, but although scientists have identified about 20 genetic variants associated with intelligence, each accounts for just 1% of the variation in IQ scores. Because the effects of these genes on the brain are so subtle, neurologist Paul Thompson of the University of California, Los Angeles, devised a new large-scale strategy for tackling the problem. In 2009, he co-founded the ENIGMA Network, an international consortium of researchers who combine brain scanning and genetic data to study brain structure and function. Earlier this year, Thompson and his colleagues reported that they had identified genetic variants associated with head size and the volume of the hippocampus, a brain structure that is crucial for learning and memory. One of these variants was also weakly associated with intelligence. Those carrying it scored on average 1.29 points better on IQ tests than others, making it one of the strongest candidate intelligence genes so far. The researchers have now used the same strategy to identify more genetic variants associated with brain structure and IQ. In the new study, they analyzed brain images and whole-genome data from 472 Australians, including 85 pairs of identical twins, 100 pairs of nonidentical twins, and their nontwin siblings. They identified 24 genetic variations within six different genes, all of which were linked to differences in the structural integrity of major brain pathways. © 2010 American Association for the Advancement of Science

Keyword: Genes & Behavior; Intelligence
Link ID: 16942 - Posted: 06.20.2012

By ANAHAD O'CONNOR A new study adds to growing evidence that the complications of diabetes may extend to the brain, causing declines in memory, attention and other cognitive skills. The new research showed that over the course of about a decade, elderly men and women with diabetes — primarily Type 2, the form of the disease related to obesity and inactivity — had greater drops in cognitive test scores than other people of a similar age. The more poorly managed their disease, the greater the deterioration in mental function. And the declines were seen not just in those with advanced diabetes. The researchers found that people who did not have diabetes at the start of the study but developed it later on also deteriorated to a greater extent than those without the disease. “What we’ve shown is a clear association with diabetes and cognitive aging in terms of the slope and the rate of decline on these cognitive tests,” said Dr. Kristine Yaffe, a professor of psychiatry and neurology at the University of California, San Francisco. “That’s very powerful.” While correlation does not equal causation and the relationship between diabetes and brain health needs further study, the findings, if confirmed, could have significant implications for a large segment of the population. Nationwide, nearly a third of Americans over the age of 65, or roughly 11 million people, have diabetes. By 2034, about 15 million Medicare-eligible Americans are expected to have the disease. Previous studies have shown that Type 2 diabetes correlates with a higher risk of Alzheimer’s disease and dementia later in life. But how one leads to the other has not been well understood. Copyright 2012 The New York Times Company

Keyword: Obesity; Learning & Memory
Link ID: 16941 - Posted: 06.20.2012

A diet high in cholesterol may help people with a fatal genetic disease which damages the brain, according to early studies in mice. Patients with Pelizaeus-Merzbacher disease struggle to produce a fatty sheath around their nerves, which is essential for function. A study, published in Nature Medicine, showed that a high-cholesterol diet could increase production. The authors said the mice "improved dramatically". Pelizaeus-Merzbacher disease (PMD) is one of many leukodystrophies in which patients struggle to produce the myelin sheath. It protects nerve fibres and helps messages pass along the nerves. Without the sheath, messages do not travel down the nerve - resulting in a range of problems including movement and cognition. Researchers at the Max Planck Institute of Experimental Medicine, in Germany, performed a trial on mice with the disease and fed them a high cholesterol diet. The first tests were on mice when they were six weeks old, after signs of PMD had already emerged. Those fed a normal diet continued to get worse, while those fed a cholesterol-enriched diet stabilised. BBC © 2012

Keyword: Multiple Sclerosis; Genes & Behavior
Link ID: 16940 - Posted: 06.20.2012

By Ferris Jabr In the 18th century Carl Linnaeus named them lemurs, after the Latin lemures—spirits of the dead, wandering ghosts. He knew the primates roamed Madagascar’s forests at night, their large eyes brimming with moonlight, their shrill cries crashing through the treetops. One of the smallest lemurs on the island, the fat-tailed dwarf lemur, resembled a phantom in another way: it completely vanished for seven months each year. For a long time, no one understood where the fat-tailed dwarf lemur went—a remote part of the island? the spirit world?—or what it was doing all that time, but scientists had a hunch. Perhaps the lemur was hibernating. If so, it would be the only primate in the world—and one of the only tropical mammals—to do so. Given Madagascar’s climate, however, it made sense that a lemur might hibernate to survive annual periods of drought. In general, Madagascar has two seasons: the hot, wet season from November to April, and the cooler, dry season from April through October. The deciduous forests on the west coast, where many fat-tailed dwarf lemurs live, offer no open sources of water during the dry season and only fibrous fruits bereft of sugar. Perhaps, scientists reasoned, the fat-tailed dwarf lemur hunkered down and waited for the rains to return, slowing its metabolism and dropping its body temperature. It could survive off of nutrients stored in its tail, which always grew plumper as the dry season drew closer. © 2012 Scientific American

Keyword: Sleep
Link ID: 16939 - Posted: 06.20.2012

By Jillian Eugenios Yasel Lopez, 16, was fishing with a friend in Miami when their three-foot spear gun went off unexpectedly, piercing Lopez through his head. Doctors are calling his survival from the accident, nearly two weeks ago, a miracle. The gun went off unexpectedly when the teenagers were loading it with a spear, sending it straight into Lopez's skull, Tamron Hall reported on TODAY Monday. The force of the impact was so strong it knocked him into the water. Acting quickly, his friend called 911 and Lopez was soon airlifted to Miami's Jackson Memorial Hospital where doctors raced to save him. Doctors revealed details Monday about Lopez's ordeal, and how they worked to save his life. “We used a high-speed drill to drill the bone at either end to create an opening through which we could remove the spear,” one of the doctors told reporters. They first had to cut the spear to prevent it from moving and allow doctors to do tests. After the spear was cut, doctors said they were able to plan the surgery: “We were able to position him laying with his left side down, right side up, and then we were able to open a large incision." Dr. George Garcia, who helped to save Lopez's life, said that Lopez was awake and interacting with hospital staff when he arrived, though he became agitated and panicky. “We didn't know if that was a result of the injury to his brain or if he was just scared or in a lot of pain.” Dr. Garcia said that that the fact that Lopez was lucid throughout gave the doctors confidence the teenager would survive. © 2012 msnbc.com

Keyword: Brain Injury/Concussion
Link ID: 16938 - Posted: 06.20.2012

By Scicurious Before I started college, there was a sudden rage amongst my male friends. A rage for one specific thing. Not phones or computers or cars or clothes. Nope. It was for a guitar. Most of the guys I knew, in the year or two before college, suddenly became obsessed with the guitar, picking out melodies, trying to match still changing warbling voices to a hopefully tuned instrument. I couldn’t figure it out. What was up with the guitar obsession?! Some of these people were people who never had displayed a musical bent their entire lives, and here they were, sitting experimentally on the benches outside my school with guitars in hand. Finally, I asked my brother (who also, of course, had taken up the guitar), why every guy seemed to want to play the guitar. Why not the cello or the piano or the trombone or the kazoo? My brother rolled his eyes at my denseness. “For the GIRLS, of course” (And yes, specifically, they ALL wanted to play this song. I would hypothesize that about 80% of the men I know can pick out this song on the guitar. Considering that a substantial portion of the female populace does indeed have brown eyes, I realize the efficiency of this method, but for those of us with non-brown eyes, this song is IRRITATING BEYOND BELIEF. This has been a public service announcement.) © 2012 Scientific American

Keyword: Sexual Behavior; Hearing
Link ID: 16937 - Posted: 06.20.2012

By Susan Milius ALBUQUERQUE — Unbeknownst to humans, peacocks may be having infrasonic conversations. New recordings reveal that males showing off their feathers make deep rumbling sounds that are too low pitched for humans to hear. Other peacocks hear it though, Angela Freeman reported June 13 at the annual meeting of the Animal Behavior Society. When she played recordings of the newly discovered sound to peafowl, females looked alert and males were likely to shriek out a (human-audible) call. Peacocks are thus the first birds known to make and perceive noises below human hearing, Freeman said. ”Really exciting,” said Roslyn Dakin of Queen’s University in Kingston, Canada, who studies the visual allure of peacock courtship. If peacocks can rumble, she suspects that other birds may be able to, too. “I don’t think this is a weird case,” she said. Such infrasound, or noise below 20 hertz, extends below the limit of human hearing. Biologists watched creatures such as elephants for centuries before recording technology uncovered the infrasound side of those animal conversations. But making infrasound doesn’t always mean communicating with it. Recordings have picked up infrasound from another bird, the capercaillie, but playing back the sounds to those birds has so far revealed no sign that they hear or care about their own infrasound. Freeman, an animal behaviorist at the University of Manitoba, was inspired to make detailed recordings of male peacocks by her coauthor’s impression that their fanned-out feather display curved slightly forward like a shallow satellite dish. © Society for Science & the Public 2000 - 2012

Keyword: Hearing; Animal Communication
Link ID: 16936 - Posted: 06.20.2012

By Charles Q. Choi Sleep should be the great equalizer. Whatever differences might divide us during the day, the nonconsciousness that comes with nighttime should be one thing we all have in common. It ain't necessarily so. Scientists have now found significant differences exist in how people sleep in the U.S. depending on race, ethnicity and country of origin, suggesting genetic or cultural differences in shut-eye patterns. This line of research could help identify how these disparities might affect health and find better ways to improve sleep. One study looked at sleep data gathered from more than 430,000 people in the U.S. between 2004 and 2010 as part of the National Health Interview Surveys, which the U.S. Centers for Disease Control and Prevention conducts annually to monitor the country's well-being. They found that foreign-born respondents were generally more likely to sleep the recommended healthy six to eight hours each night as compared with native-born Americans. "This study is particularly interesting, because it goes to show that the unhealthy American lifestyle includes more than a poor diet and lack of exercise—it also means unhealthy sleep patterns, and this can lead to important health consequences," says sleep researcher Michael Grandner at the University of Pennsylvania, who did not take part in this research. "It seems like foreign-born Americans may be protected by not adopting this unhealthy lifestyle." © 2012 Scientific American

Keyword: Sleep
Link ID: 16935 - Posted: 06.20.2012

By Laura Sanders The Alzheimer’s-related protein amyloid-beta is an infectious instigator in the brain, gradually contorting its harmless brethren into dangerous versions, compelling new evidence shows. The study adds to the argument that A-beta is a prion, a misfolded protein that behaves like the contagious culprits behind Creutzfeldt-Jakob disease in people, scrapie in sheep and mad cow disease. There’s no evidence that Alzheimer’s can spread from person to person, but thinking of Alzheimer’s as a prion disease could change the way researchers approach treatment and prevention strategies. The results also raise troubling implications for people who participated in a clinical trial in which they received a form of A-beta made in the lab, Stanley Prusiner of the University of California, San Francisco and colleagues write online June 18 in the Proceedings of the National Academy of Sciences. In the study, the researchers injected purified A-beta protein to seed one side of mice’s brains and monitored it with a fluorescent molecule that became visible as the protein accumulated. After about 300 days, the A-beta had accumulated throughout the brain, similar to what happens in Alzheimer’s. “It really does spread,” says study coauthor Kurt Giles of UCSF. “We inoculate in one part of the brain but the pathology spreads through the whole brain.” © Society for Science & the Public 2000 - 2012

Keyword: Alzheimers; Prions
Link ID: 16934 - Posted: 06.20.2012

By DAVID TULLER Late one evening last December, 18-year-old Michelle Vaquero was crossing a busy street in San Jose, Calif., when a car slammed into her. She landed more than 30 feet away. An ambulance rushed her to Santa Clara Valley Medical Center, where doctors diagnosed traumatic brain injury. Miriam Richards, Ms. Vaquero’s mother, said that doctors at first offered little cause for optimism. “The impact was so severe that they didn’t give us any hope,” she said. “They didn’t tell us she’d be fine. They didn’t know how bad it was.” Ms. Vaquero has been steadily recovering since the accident, and there is reason for Ms. Richards to hope that progress will continue. Shortly after she arrived at the hospital, Ms. Vaquero was enrolled in a study examining whether a surprising new treatment could minimize the damage to her brain: a three-day infusion of progesterone, the reproductive hormone. The study, financed by the National Institutes of Health and overseen by Emory University in Atlanta, is designed to test the hypothesis that the hormone can reduce mortality and disability if administered right after a traumatic brain injury. Patients must begin the infusion within four hours of the injury, with outcomes assessed after six months. The study is one of two large trials of progesterone that have generated excitement among doctors because no medications have been approved for preventing the worst outcomes associated with serious brain injuries. Dr. David Gordon, an assistant professor of neurosurgery at Montefiore Medical Center in the Bronx who is not involved in the research, said that he has “some measure of cautious optimism” about progesterone. © 2012 The New York Times Company

Keyword: Brain Injury/Concussion; Hormones & Behavior
Link ID: 16933 - Posted: 06.19.2012

by Dennis Normile YOKOHAMA, JAPAN—For more than a decade, stem cell therapies have been touted as offering hope for those suffering from genetic and degenerative diseases. The promise took another step toward reality last week with announcements here at the annual meeting of the International Society for Stem Cell Research (ISSCR) that two groups are moving forward with human clinical research, one focusing on a rare genetic neurological disease and the other for the loss of vision in the elderly. StemCells Inc. of Newark, California, reported encouraging results of an initial human trial using human neural stem cells to treat Pelizaeus-Merzbacher disease (PMD). PMD is a progressive and fatal disorder in which a genetic mutation inhibits the normal growth of myelin, a protective material that envelopes nerve fibers in the brain. Without myelin, nerve signals are lost, and the patient, usually an infant, suffers degenerating motor coordination and other neurological symptoms. In her presentation, Ann Tsukamoto, StemCells' vice president for research, said the company chose to test its neural stem cell approach on PMD because there is currently no treatment for the condition and a diagnosis can be confirmed by genetic testing and magnetic resonance imaging. "This creates an opportunity for early intervention when it can best help." The company has created banks of highly purified neural stem cells that are isolated from adult neural tissue. Injected into rodents, the cells don't form tumors; rather, they migrate through the animals' brains, where they differentiate into various types of neural cells including the cells that create the myelin that protects nerve fibers. When neural stem stems were injected into in mice, they showed "robust engraftment and migration, the formation of new myelin," Tsukamoto said. © 2010 American Association for the Advancement of Science

Keyword: Stem Cells; Genes & Behavior
Link ID: 16932 - Posted: 06.19.2012

Adults who had a common bariatric surgery to lose weight had a significantly higher risk of alcohol use disorders (AUD) two years after surgery, according to a study by a National Institutes of Health research consortium. Researchers investigated alcohol consumption and alcohol use disorders symptoms in 1,945 participants from the NIH-funded Longitudinal Assessment of Bariatric Surgery (LABS), a prospective study of patients undergoing weight-loss surgery at one of 10 hospitals across the United States. Within 30 days before surgery, and again one and two years after surgery, study participants completed the Alcohol Use Disorders Identification (AUDIT) test. The test, developed by the World Health Organization, identifies symptoms of alcohol use disorders, a condition that includes alcohol abuse and dependence, commonly known as alcoholism. Study participants were categorized as having AUD if they had at least one symptom of alcohol dependence, which included not being able to stop drinking once started, or alcohol-related harm, which included not being able to remember, or if their total AUDIT score was at least 8 (out of 40). About 70 percent of the study participants had Roux-en-Y (RYGB) gastric bypass surgery, which reduces the size of the stomach and shortens the intestine, limiting food intake and the body's ability to absorb calories. Another 25 percent had laparoscopic adjustable gastric banding surgery, which makes the stomach smaller with an adjustable band. About 5 percent of the patients had other, less common weight-loss surgeries.

Keyword: Obesity; Drug Abuse
Link ID: 16931 - Posted: 06.19.2012

By Justin Moyer, On June 9, Commerce Secretary John Bryson was hospitalized after his reported involvement in three auto accidents. Although details were not disclosed, the White House confirmed that he had a seizure. On July 30, 2007, Chief Justice John Roberts collapsed on a boat dock at his Maine summer home. Although that seizure was Roberts’s second, he offered little explanation. When Time magazine asked “Does Justice Roberts Have Epilepsy?,” Roberts didn’t answer, and he hasn’t in five years. Reading these stories, I wish public figures such as Roberts and Bryson would talk publicly about their conditions. They should do this not because they are legally compelled to or because their health may affect their work. They should do it because hiding their problems makes it seem like their problems are worth hiding. I received a diagnosis of epilepsy in 2001, at age 24. My seizures are generalized, meaning they strike my whole brain and body. Without warning, I lose consciousness for several minutes and remain disoriented for a few hours. Later, I have no memory of the episode save muscle aches and a sore mouth from biting my tongue. My seizures are idiopathic: They have no known cause. They can be controlled with levetiracetam, a medication that regulates brain neurotransmitters. © 1996-2012 The Washington Post

Keyword: Epilepsy
Link ID: 16930 - Posted: 06.19.2012

By ANDREW POLLACK Two of the front-runners in the race to develop drugs to treat mental retardation and autism are joining forces, hoping to save money and get to the market sooner. A deal, expected to be announced on Tuesday, will pool the resources of Roche, the Swiss pharmaceutical giant, and Seaside Therapeutics, a private 30-employee company based in Cambridge, Mass. “This deal will establish the biggest effort to date” in autism drugs, Luca Santarelli, head of neuroscience for Roche, said before the announcement. Financial terms are not being disclosed. There is rising excitement that drugs might be able to relieve some of the behavioral problems associated with autism and in particular a cause of autism and mental retardation known as fragile X syndrome. About 100,000 Americans have fragile X syndrome. Some parents of children being treated with new drugs in clinical trials have said they see positive changes in behavior. Becky Zorovic of Sharon, Mass., said that when she used to take her son Anders, who has fragile X, to the dentist, she would have to lie in the chair and hold him on top of her as he screamed. But after Anders starting taking Seaside’s drug, arbaclofen, in a clinical trial, she said, “He sat in the chair by himself and he opened his mouth and let the dentist polish his teeth and even scrape his teeth.” Anders has also has gone to birthday parties, which he once refused to do, she said. © 2012 The New York Times Company

Keyword: Autism
Link ID: 16929 - Posted: 06.19.2012

by Veronique Greenwood An average human, utterly unremarkable in every way, can 
perceive a million different colors. Vermilion, puce, cerulean, periwinkle, chartreuse—we have thousands of words for them, but mere language can never capture our extraordinary range of hues. Our powers of color vision derive from cells in our eyes called cones, three types in all, each triggered by different wavelengths of light. Every moment our eyes are open, those three flavors of cone fire off messages to the brain. The brain then combines the signals to produce the sensation we call color. Vision is complex, but the calculus of color is strangely simple: Each cone confers the ability to distinguish around a hundred shades, so the total number of combinations is at least 1003, or a million. Take one cone away—go from being what scientists call a trichromat to a dichromat—and the number of possible combinations drops a factor of 100, to 10,000. Almost all other mammals, including dogs and New World monkeys, are dichromats. The richness of the world we see is rivaled only by that of birds and some insects, which also perceive the ultraviolet part of the spectrum. Researchers suspect, though, that some people see even more. Living among us are people with four cones, who might experience a range of colors invisible to the rest. It’s possible these so-called tetrachromats see a hundred million colors, with each familiar hue fracturing into a hundred more subtle shades for which there are no names, no paint swatches. And because perceiving color is a personal experience, they would have no way of knowing they see far beyond what we consider the limits of human vision. © 2012, Kalmbach Publishing Co.

Keyword: Vision
Link ID: 16928 - Posted: 06.19.2012

Neuroscientist and friend of the blog Bradley Voytek has a terrific piece about the relationship between popular science writing and neuroscience that’s well worth your time. In brief, he says, the primary problem are neuroscientists themselves. Or at least, some of the assumptions that neuroscientists make. The problem, he notes, is a problem that long term readers here are familiar with – the confusion of cause and effect, as well as an over-reductionist view of the brain. Namely, that imaging studies showing a portion of the brain “lighting up” when something happens means that that area of the brain is directly involved in the activity. Something that he analogizes to “like how when your arms swing faster when you run that means that your arms are ‘where running happens’.” Voytek also provides what I think is one of the best analogies I’ve read about the problem inherent in trying to isolate “which part of the brain does X”: Imagine asking “where is video located in my computer?” That doesn’t make any sense. Your monitor is required to see the video. Your graphics card is required to render the video. The software is required to generate the code for the video. But the “video” isn’t located anywhere in the computer. This is something that I think is exactly right. The best neuroscientists out there are, I think, very aware of this problem, but I think part of what’s going on here is the inherent limitations of our ability to experiment. Take fMRI’s, for example, which have provided an interesting look into what kinds of activity is going on in the brain while the person being imaged is doing or thinking something. It’s one of the best pieces of equipment available, but it’s very nature can be deceiving. Because it’s one of the few ways available to figure out what’s going on in the brain, it can be tempting to see what is measured by an fMRI image as definitive. 2012 Forbes.com LLC™

Keyword: Brain imaging
Link ID: 16927 - Posted: 06.19.2012

By Susan Milius ALBUQUERQUE — Baby bluebirds don’t survive as well near rumbling traffic and other human din as they do amid natural lullabies. In a Virginia study, 35 percent more chicks died in the noisiest nests than in the most remote ones. Researchers found that chicks didn’t adjust for the noise by begging louder or at different frequencies. So parents may not have gotten the right cues for nestling care, behavioral ecologist John Swaddle suggested June 12 at the annual meeting of the Animal Behavior Society. Until recently, most research on how human-made noise discombobulates birds has focused on how adults adjust their songs (or don’t) or on what species will nest at all among the din. Research is now turning to how noise might directly affect the success of a species. One earlier study on reproductive success, in common European birds called great tits, found smaller clutches near roaring highways. Clutch size didn’t shrink among eastern bluebirds (Sialia sialis), said Swaddle, a professor at the College of William and Mary in Williamsburg, Va. Birds settling in to the 43 nest boxes he and his colleagues monitored for two years all started with about the same number of eggs. Just what made noisier nests less successful after hatching isn’t clear, but Swaddle suspects that noise kept parents from caring for their nestlings properly. Noise might have made food harder to find, or it might have masked normal parent-chick chat. Even though baby birds have become an icon of endlessly demanding maws, parents do tune their feeding effort to begging calls, and research has confirmed the importance of communication. © Society for Science & the Public 2000 - 2012

Keyword: Animal Communication; Stress
Link ID: 16926 - Posted: 06.19.2012