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By DAVID LEVINE MONTREAL — When twins have similar personalities, is it mainly because they share so much genetic material or because their physical resemblance makes other people treat them alike? Most researchers believe the former, but the proposition has been hard to prove. So Nancy L. Segal, a psychologist who directs the Twin Studies Center at California State University, Fullerton, decided to test it — and enlisted an unlikely ally. He is François Brunelle, a photographer in Montreal who takes pictures of pairs of people who look alike but are not twins. Dr. Segal was sent to Mr. Brunelle’s website by a graduate student who knew of her research with twins. When she saw the photographs, she realized that the unrelated look-alikes would be ideal study subjects: She could compare their similarities and differences to those of actual twins. “I reasoned that if personality resides in the face,” she said, “then unrelated look-alikes should be as similar in behavior as identical twins reared apart. Alternatively, if personality traits are influenced by genetic factors, then unrelated look-alikes should show negligible personality similarity.” For 14 years, Mr. Brunelle, 64, has been working on a project he calls “I’m Not a Look-Alike!”: more than 200 black-and-white portraits of pairs who do, in fact, look startlingly alike. “I originally named the project ‘Look-Alikes,’ but I felt it was boring and some of the subjects did not feel they looked alike,” he said. “The new name gives ownership to the people I photographed and allows viewers of my website to decide for themselves if the people look alike or not.” Most come to him through social media links to his website. “It has taken on a life of its own,” he said. “I have heard from people in China — and even a man who has an uncle in Uzbekistan who is a dead ringer for former President George W. Bush.” © 2014 The New York Times Company
Keyword: Genes & Behavior
Link ID: 19997 - Posted: 08.26.2014
Erin Allday When a person suddenly loses the ability to speak or to understand what others are saying, the hardships that cascade from that loss can be overwhelming - from the seemingly trite to the devastatingly depressing. What hit Derrick Wong, 49, hardest was losing the ability to tell a joke. Ralph Soriano, 56, hates taking his car to the mechanic, knowing he will barely understand what's being said. "Girls," said Luke Waterman, 30, with a sigh. Flirting used to come easy. All three men - actually a pretty happy, hopeful gang for the most part - are longtime members of a group therapy program at the Aphasia Center of California, an Oakland nonprofit that offers treatment and ongoing education to people who have suffered communication disorders as a result of stroke or other brain injury. The nonprofit specializes in long-term therapy, an area of aphasia treatment that has taken off in the past few years. For many decades, doctors and speech pathologists assumed that patients had a window of six months to a year to recover language skills lost to a brain injury. Now, anecdotal reports and clinical research suggest that the window is much wider, and may even stay open a lifetime. "There is evidence that people can improve and regain skills, even years after a stroke," said Blair Menn, a speech language pathologist at Kaiser Permanente Medical Center in Redwood City. © 2014 Hearst Communications, Inc.
By NICHOLAS BAKALAR Childhood treatment with human growth hormone is strongly associated with an increased risk for stroke in early adulthood, a new study has found. The study adds evidence to previous reports suggesting an increased cardiac and cerebrovascular risk in children treated with growth hormone. Researchers studied 6,874 children, average age 11, who were small for their age but otherwise generally healthy and were treated with growth hormone from 1985 to 1996. They followed them to an average age of 28. There were 11 strokes in the group, four of them fatal. The analysis found that this was more than twice as many strokes as would be expected in a population this size, a statistically significant difference. The results, published online in the journal Neurology, were particularly striking for hemorrhagic stroke, the type caused by a ruptured blood vessel — there were more than seven times as many as would be expected. The authors acknowledged that they were unable to take into account some risk factors for stroke, such as family history and smoking. “Subjects on growth hormones should not panic on reading these results,” said the senior author, Dr. Joël Coste, a professor of biostatistics and epidemiology at the Hôtel Dieu hospital in Paris. “The doctor prescribing the hormone or the family doctor should be consulted and will be able to inform and advise patients.” © 2014 The New York Times Company
by Jennifer Viegas Spritzing dogs with a “pig perfume” helps prevent them from barking incessantly, jumping frantically on house guests and from engaging in other unwanted behaviors, according to new research. The eau de oink, aka “Boar Mate” or “Stop That,” was formulated by Texas Tech scientist John McGlone, who was looking for a way to curb his Cairn terrier Toto’s non-stop barking. One spritz of the pig perfume seemed to do the trick in an instant without harming his dog. “It was completely serendipitous,” McGlone, who works in the university’s Animal and Food Sciences department of the College of Agriculture and Natural Sciences, said in a press release. “One of the most difficult problems is that dogs bark a lot, and it’s one of the top reasons they are given back to shelters or pounds.” The key ingredient is androstenone, a steroid and pheromone produced by male pigs and released in their saliva and fat. When detected by female pigs in heat, they seem to find the male more attractive. (The females assume a mating stance.) One can imagine that dogs spritzed with the scent should not hang around amorous female pigs, but other than that, the product seems to work, according to McGlone. Androstenone smells pungent and is not very appealing to humans, but it can have an effect on mammal behavior, he said. © 2014 Discovery Communications, LLC.
Keyword: Chemical Senses (Smell & Taste)
Link ID: 19994 - Posted: 08.26.2014
By Chelsea Rice Opioid-related overdose deaths are a bleak public health issue in this country. The percentage of patients who receive opioid prescriptions to treat noncancer pain has almost doubled in the past decade, but the number of overdose-related deaths for women have increased five times as much, according to the Centers for Disease Control and Prevention. To put the nationwide stats in perspective, more women have died each year from drug overdoses than from motor vehicle-related injuries since 2007. For men in the past decade, the rate of opioid overdose deaths has increased three-fold. According to the CDC, women in particular are more likely to be prescribed opioid pain relievers than men, more likely to use them chronically, and more likely to be prescribed them in higher doses. But what if medical marijuana, another option for treating chronic pain, could have an impact on these staggering statistics? Research published today in JAMA Internal Medicine found that states with medical marijuana laws before 2010 had 24.8 percent lower annual opioid overdose deaths on average when compared to states where medical marijuana was illegal. Medical cannabis laws were associated in the study with lower overdose mortality rates that generally strengthened over time. In 2010, for instance, researchers noticed there were 1,729 fewer deaths in states where medical marijuana was legal. The research team, lead by Dr. Marcus A. Bachhuber at the Philadelphia Veterans Affairs Medical Center, examined state medical marijuana laws and opioid overdose deaths using death certificate data from 1999 to 2010.
Keyword: Drug Abuse
Link ID: 19993 - Posted: 08.26.2014
By Sandra G. Boodman When the Philadelphia specialist gently tweaked a spot deep inside Heidi Gribble Camp’s back, she screamed, an expression of both anguish and elation.Camp’s vindication was fueled in large part by her persistence. In 2006, her complaints of severe abdominal pain early in her first pregnancy were brushed aside by her doctor — until she nearly bled to death from a ruptured ectopic pregnancy. That near-fatal hemorrhage was swiftly followed by her sudden lapse into unconsciousness and the discovery of large blood clots in her lung and abdomen, requiring additional emergency surgery. “I told him, ‘You found the pain, this is the best day of my life!’ ” Camp, 32, recalled saying during the June 18 procedure at the Hospital of the University of Pennsylvania. The fact that the interventional radiologist, an expert in minimally invasive surgical procedures, was able to pinpoint and replicate the stabbing pain she had suffered for more than eight years was sweet validation. It proved that Camp wasn’t exaggerating her pain and that it had an identifiable, physical cause, something a series of doctors had come to doubt. Months of recovery followed — as did the first episode of searing back pain. But doctors in Florida, Toronto and Northern Virginia, where Camp lived at various times with her husband, a recently retired professional baseball player — told her they could not find a reason for her agony. Some implied that she was dramatizing normal aches; others rebuffed her inquires about a potential cause that would later prove to be prescient.
Keyword: Pain & Touch
Link ID: 19992 - Posted: 08.26.2014
by Penny Sarchet It's a selfie that might save your sight. An implanted sensor could help people with glaucoma monitor the pressure in their eyes using a smartphone camera. The second biggest cause of blindness after cataracts, glaucoma occurs when fluid builds up in the eye. This raises the pressure, damaging the optic nerve. Accurate pressure readings are crucial for giving the right treatment, but one-off measurements during check-ups produce variable results and can be misleading. Yossi Mandel at Bar-Ilan University in Ramat Gan, Israel, and his colleagues have developed a pressure sensor which can be inserted into the eye during surgery to provide easy, regular monitoring from home. A few millimetres in length, the sensor can be embedded into the synthetic lenses used to replace the natural lenses of people with cataracts. It works like a miniature barometer, and contains a fluid column that rises with eye pressure. The level can be read at any time using a smartphone camera fitted with a special optical adapter. Software then analyses the image and calculates the reading. "Continuous monitoring is a clear unmet need in glaucoma," says Francesca Cordeiro, a glaucoma researcher at University College London. Mandel believes self-monitoring will lead to better treatment of glaucoma, and could enable people to skip unnecessary appointments when their eye pressures are on target. © Copyright Reed Business Information Ltd.
By DAVE PHILIPPS WRAY, Colo. — Behind a tall curtain of corn that hides their real cash crop from prying eyes, the Stanley family is undertaking an audacious effort to expand their medical marijuana business to a national market. For years, the five Stanley brothers, who sell a nonintoxicating strain of cannabis that has gained national attention as a treatment for epilepsy, have grown medical marijuana in greenhouses, under tight state and federal regulations. But this year, they are not only growing marijuana outdoors by the acre, they also plan to ship an oil extracted from their plants to other states. The plan would seem to defy a federal prohibition on the sale of marijuana products across state lines. But the Stanleys have justified it with a simple semantic swap: They now call their crop industrial hemp, based on its low levels of THC, the psychoactive ingredient in pot. “The jump to industrial hemp means we can serve thousands of people instead of hundreds,” said Jared Stanley, 27, who wore muddy Carhartts and a rainbow friendship bracelet as he knelt down to prune his plants. Colorado, which has legalized the sale of marijuana for recreational and medical use, has accepted the new designation. But the real question is whether the federal government will go along. If it does, the impact would be significant, opening the door to interstate sales not just by the Stanleys, but possibly by scores of other medical cannabis growers across the country. But if it does not, the Stanley brothers could be shut down by federal agents. So far, the Drug Enforcement Administration is offering few clues, insisting in public statements that while it is willing to allow marijuana sales in states that have legalized the drug, it might step in if growers try to sell beyond state borders. © 2014 The New York Times Company
Keyword: Drug Abuse
Link ID: 19990 - Posted: 08.25.2014
|By Mark Fischetti Parents, students and teachers often argue, with little evidence, about whether U.S. high schools begin too early in the morning. In the past three years, however, scientific studies have piled up, and they all lead to the same conclusion: a later start time improves learning. And the later the start, the better. Biological research shows that circadian rhythms shift during the teen years, pushing boys and girls to stay up later at night and sleep later into the morning. The phase shift, driven by a change in melatonin in the brain, begins around age 13, gets stronger by ages 15 and 16, and peaks at ages 17, 18 or 19. Does that affect learning? It does, according to Kyla Wahlstrom, director of the Center for Applied Research and Educational Improvement at the University of Minnesota. She published a large study in February that tracked more than 9,000 students in eight public high schools in Minnesota, Colorado and Wyoming. After one semester, when school began at 8:35 a.m. or later, grades earned in math, English, science and social studies typically rose a quarter step—for example, up halfway from B to B+. Two journal articles that Wahlstrom has reviewed but have not yet been published reach similar conclusions. So did a controlled experiment completed by the U.S. Air Force Academy, which required different sets of cadets to begin at different times during their freshman year. A 2012 study of North Carolina school districts that varied school times because of transportation problems showed that later start times correlated with higher scores in math and reading. Still other studies indicate that delaying start times raises attendance, lowers depression rates and reduces car crashes among teens, all because they are getting more of the extra sleep they need. © 2014 Scientific American
By PAM BELLUCK As a baby’s brain develops, there is an explosion of synapses, the connections that allow neurons to send and receive signals. But during childhood and adolescence, the brain needs to start pruning those synapses, limiting their number so different brain areas can develop specific functions and are not overloaded with stimuli. Now a new study suggests that in children with autism, something in the process goes awry, leaving an oversupply of synapses in at least some parts of the brain. The finding provides clues to how autism develops from childhood on, and may help explain some symptoms like oversensitivity to noise or social experiences, as well as why many people with autism also have epileptic seizures. It could also help scientists in the search for treatments, if they can develop safe therapies to fix the system the brain uses to clear extra synapses. The study, published Thursday in the journal Neuron, involved tissue from the brains of children and adolescents who had died from ages 2 to 20. About half had autism; the others did not. The researchers, from Columbia University Medical Center, looked closely at an area of the brain’s temporal lobe involved in social behavior and communication. Analyzing tissue from 20 of the brains, they counted spines — the tiny neuron protrusions that receive signals via synapses — and found more spines in children with autism. The scientists found that at younger ages, the number of spines did not differ tremendously between the two groups of children, but adolescents with autism had significantly more than those without autism. Typical 19-year-olds had 41 percent fewer synapses than toddlers, but those in their late teenage years with autism had only 16 percent fewer than young children with autism. © 2014 The New York Times Company
By Meeri Kim From ultrasonic bat chirps to eerie whale songs, the animal kingdom is a noisy place. While some sounds might have meaning — typically something like “I'm a male, aren't I great?” — no other creatures have a true language except for us. Or do they? A new study on animal calls has found that the patterns of barks, whistles, and clicks from seven different species appear to be more complex than previously thought. The researchers used mathematical tests to see how well the sequences of sounds fit to models ranging in complexity. In fact, five species including the killer whale and free-tailed bat had communication behaviors that were definitively more language-like than random. The study was published online Wednesday in the Proceedings of the Royal Society B. “We're still a very, very long way from understanding this transition from animal communication to human language, and it's a huge mystery at the moment,” said study author and zoologist Arik Kershenbaum, who did the work at the National Institute for Mathematical and Biological Synthesis. “These types of mathematical analyses can give us some clues.” While the most complicated mathematical models come closer to our own speech patterns, the simple models — called Markov processes — are more random and have been historically thought to fit animal calls. “A Markov process is where you have a sequence of numbers or letters or notes, and the probability of any particular note depends only on the few notes that have come before,” said Kershenbaum. So the next note could depend on the last two or 10 notes before it, but there is a defined window of history that can be used to predict what happens next. “What makes human language special is that there's no finite limit as to what comes next,” he said.
By Jane C. Hu Last week, people around the world mourned the death of beloved actor and comedian Robin Williams. According to the Gorilla Foundation in Woodside, California, we were not the only primates mourning. A press release from the foundation announced that Koko the gorilla—the main subject of its research on ape language ability, capable in sign language and a celebrity in her own right—“was quiet and looked very thoughtful” when she heard about Williams’ death, and later became “somber” as the news sank in. Williams, described in the press release as one of Koko’s “closest friends,” spent an afternoon with the gorilla in 2001. The foundation released a video showing the two laughing and tickling one another. At one point, Koko lifts up Williams’ shirt to touch his bare chest. In another scene, Koko steals Williams’ glasses and wears them around her trailer. These clips resonated with people. In the days after Williams’ death, the video amassed more than 3 million views. Many viewers were charmed and touched to learn that a gorilla forged a bond with a celebrity in just an afternoon and, 13 years later, not only remembered him and understood the finality of his death, but grieved. The foundation hailed the relationship as a triumph over “interspecies boundaries,” and the story was covered in outlets from BuzzFeed to the New York Post to Slate. The story is a prime example of selective interpretation, a critique that has plagued ape language research since its first experiments. Was Koko really mourning Robin Williams? How much are we projecting ourselves onto her and what are we reading into her behaviors? Animals perceive the emotions of the humans around them, and the anecdotes in the release could easily be evidence that Koko was responding to the sadness she sensed in her human caregivers. © 2014 The Slate Group LLC.
|By Jason G. Goldman When you do not know the answer to a question, say, a crossword puzzle hint, you realize your shortcomings and devise a strategy for finding the missing information. The ability to identify the state of your knowledge—thinking about thinking—is known as metacognition. It is hard to tell whether other animals are also capable of metacognition because we cannot ask them; studies of primates and birds have not yet been able to rule out simpler explanations for this complex process. Scientists know, however, that some animals, such as western scrub jays, can plan for the future. Western scrub jays, corvids native to western North America, are a favorite of cognitive scientists because they are not “stuck in time”—that is, they are able to remember past events and are known to cache their food in anticipation of hunger, according to psychologist Arii Watanabe of the University of Cambridge. But the question remained: Are they aware that they are planning? Watanabe devised a way to test them. He let five birds watch two researchers hide food, in this case a wax worm. The first researcher could hide the food in any of four cups lined up in front of him. The second had three covered cups, so he could place the food only in the open one. The trick was that the researchers hid their food at the same time, forcing the birds to choose which one to watch. If the jays were capable of metacognition, Watanabe surmised, the birds should realize that they could easily find the second researcher's food. The wax worm had to be in the singular open cup. They should instead prefer keeping their eyes on the setup with four open cups because witnessing where that food went would prove more useful in the future. And that is exactly what happened: the jays spent more time watching the first researcher. The results appeared in the July issue of the journal © 2014 Scientific American,
by Sarah Zielinski PRINCETON, N.J. — Learning can be a quick shortcut for figuring out how to do something on your own. The ability to learn from watching another individual — called social learning — is something that hasn’t been documented in many species outside of primates and birds. But now a lizard can be added to the list of critters that can learn from one another. Young eastern water skinks were able to learn by watching older lizards, Martin Whiting of Macquarie University in Sydney reported August 10 at the Animal Behavior Society meeting at Princeton University. The eastern water skink, which reaches a length of about 30 centimeters, can be found near streams and waterways in eastern Australia. The lizards live up to eight years, and while they don’t live in groups, they often see each other in the wild. That could provide an opportunity for learning from each other. Whiting and his colleagues worked with 18 mature (older than 5 years) and 18 young (1.5 to 2 years) male skinks in the lab. The lizards were placed in bins with a barrier in the middle that was either opaque or transparent. In the first of two experiments, the skinks were given a yellow-lidded container with a mealworm inside. They had to learn to open the lid to get the food. In that task, skinks that could see a demonstrator through a transparent barrier were no better at opening the lid than those who had to figure it out on their own. After watching a demonstrator lizard (top row), the skink in the other half of the tub was supposed to have learned that a mealworm was beneath the blue lid. The skink in the middle arena, however, failed the task when he opened the white lid first.D.W.A. Noble et al/Biology Letters 2014 © Society for Science & the Public 2000 - 2013.
by Philippa Skett It's the strangest sweet tooth in the world. Birds lost the ability to taste sugars, but nectar-feeding hummingbirds re-evolved the capacity by repurposing receptors used to taste savoury food. To differentiate between tastes, receptors on the surface of taste buds on the tongue, known as T1Rs, bind to molecules in certain foods, triggering a neurological response. In vertebrates such as humans, a pair of these receptors – T1R2 and T1R3 – work together to deliver the sweet kick we experience from sugar. But Maude Baldwin at Harvard University and her colleagues found that birds don't have the genes that code for T1R2. They are found in lizards, though, suggesting that they were lost at some point during the evolution of birds or the dinosaurs they evolved from. But hummingbirds clearly can detect sugar: not only do they regularly sup on nectar, taste tests show they prefer sweet tasting foods over blander options. Now Baldwin and her team have worked out why: another pair of receptors – T1R1 and T1R3 – work together to detect sugar. Other vertebrates use T1R1 to taste savoury foods. It seems that in hummingbirds the proteins on the surface of the two receptors have been modified so that they respond to sugars instead. © Copyright Reed Business Information Ltd.
By ELEANOR LEW I was watching Diane Sawyer on the evening news, wondering how she manages year after year to look so young, when suddenly her face disappeared. Now you see. Now you don’t. One second. That’s all it took. A dense black inkblot shaped like a map of England and southern Norway suddenly blocked my view of Diane so that all I could see was her blond hair and shoulders. At first, I thought it was the television set. Changing channels didn’t bring her face back, nor did rubbing my eyes. “It’s permanent vision loss,” my ophthalmologist said. “Your optic nerve and retina buckled.” He drew a picture of the inside of my right eye, the affected one, and explained that my degenerative myopia, an inherited condition that is far less common than ordinary nearsightedness but still a leading cause of blindness worldwide, had caused my eyeball to elongate excessively. It looked like a house whose walls had been stretched so thin that the roof caved. The doctor didn’t say much else, didn’t make any recommendations for physical or occupational therapy, didn’t tell me to call him if I noticed any changes. I left his office shaken. “What if it happens in my other eye? What if…?” In the weeks that followed, I began to notice bizarre changes in my right eye. Frequent flashing lights, like a dying neon tube, sometimes flickering color or bright white light, so intense I swore I could hear them buzz. I observed my peripheral vision diminishing. England and Norway morphed into a large, bushy oak tree with a short and wide trunk. At a park, I came upon children playing. When I covered my good eye with my hand, I could see only a sliver of sky, and legs and shoes of children running in and out of the tree. I wrote off the psychedelic changes to the “buckling” and didn’t bother to call my ophthalmologist. But I was scared and needed help. © 2014 The New York Times Company
Link ID: 19982 - Posted: 08.22.2014
By CARL ZIMMER Your body is home to about 100 trillion bacteria and other microbes, collectively known as your microbiome. Naturalists first became aware of our invisible lodgers in the 1600s, but it wasn’t until the past few years that we’ve become really familiar with them. This recent research has given the microbiome a cuddly kind of fame. We’ve come to appreciate how beneficial our microbes are — breaking down our food, fighting off infections and nurturing our immune system. It’s a lovely, invisible garden we should be tending for our own well-being. But in the journal Bioessays, a team of scientists has raised a creepier possibility. Perhaps our menagerie of germs is also influencing our behavior in order to advance its own evolutionary success — giving us cravings for certain foods, for example. “One of the ways we started thinking about this was in a crime-novel perspective,” said Carlo C. Maley, an evolutionary biologist at the University of California, San Francisco, and a co-author of the new paper. “What are the means, motives and opportunity for the microbes to manipulate us? They have all three.” The idea that a simple organism could control a complex animal may sound like science fiction. In fact, there are many well-documented examples of parasites controlling their hosts. Some species of fungi, for example, infiltrate the brains of ants and coax them to climb plants and clamp onto the underside of leaves. The fungi then sprout out of the ants and send spores showering onto uninfected ants below. How parasites control their hosts remains mysterious. But it looks as if they release molecules that directly or indirectly can influence their brains. © 2014 The New York Times Company
by Bethany Brookshire When a laboratory mouse and a house mouse come nose to nose for the first time, each one is encountering something it has never seen before. They are both Mus musculus. But the wild mouse is facing a larger, fatter, calmer and less aggressive version of itself that’s the result of brother-to-sister inbreeding for generations, resulting in mice that are almost completely genetically identical. Laboratory mice are incredibly valuable tools for research into diseases from Alzheimer’s to Zellweger syndrome. Scientists have a deep understanding of lab mouse DNA, and can use that knowledge to study how specific genes may control certain behaviors and underlie disease. But with all the inbreeding comes some traits that, while desirable in a lab mouse, may not reflect the behavior of an animal in the wild. So for some questions, and some behaviors, scientists might need something a bit wilder. A new study takes lab mice back to their roots and along the way uncovers a new gene function. Lea Chalfin and colleagues at the Weizmann Institute of Science in Rohovot, Israel, bred laboratory mice with wild mice for 10 generations. The result was a mouse with wild mouse genes and wild mouse behavior — with a few important lab mouse genes mixed in. The technique allows scientists to place specific mutations in a wild mouse. The results have interesting implications for studying the mouse species, and might provide some new ways to study human disease as well. Chalfin and her colleagues were especially interested in behaviors linked to female aggression. © Society for Science & the Public 2000 - 2013
By James Gallagher Health editor, BBC News website Stimulating the part of the brain which controls movement may improve recovery after a stroke, research suggests. Studies showed firing beams of light into the brains of mice led to the animals moving further and faster than those without the therapy. The research, published in Proceedings of the National Academy of Science, could help explain how the brain recovers and lead to new treatments. The Stroke Association said the findings were interesting. Strokes can affect memory, movement and the ability to communicate. Brain cells die when their supply of oxygen and sugars is cut off by a blood clot. Stroke care is focused on rapid treatment to minimise the damage, but some recovery is possible in the following months as the brain rewires itself. The team at Stanford University School of Medicine investigated whether brain stimulation aided recovery in animal experiments. They used a technique called optogenetics to stimulate just the neurons in the motor cortex - the part of the brain responsible for voluntary movements - following a stroke. After seven days of stimulation, mice were able to walk further down a rotating rod than mice which had not had brain stimulation. After 10 days they were also moving faster. The researchers believe the stimulation is affecting how the wiring of the brain changes after a stroke. They detected higher levels of chemicals linked to the formation of new connections between brain cells. Lead researcher Prof Gary Steinberg said it was a struggle to give people drugs to protect brain cells in time as the "time window is very short". BBC © 2014
Link ID: 19979 - Posted: 08.20.2014
|By Matthew H. Schneps “There are three types of mathematicians, those who can count and those who can’t.” Bad joke? You bet. But what makes this amusing is that the joke is triggered by our perception of a paradox, a breakdown in mathematical logic that activates regions of the brain located in the right prefrontal cortex. These regions are sensitive to the perception of causality and alert us to situations that are suspect or fishy — possible sources of danger where a situation just doesn’t seem to add up. Many of the famous etchings by the artist M.C. Escher activate a similar response because they depict scenes that violate causality. His famous “Waterfall” shows a water wheel powered by water pouring down from a wooden flume. The water turns the wheel, and is redirected uphill back to the mouth of the flume, where it can once again pour over the wheel, in an endless cycle. The drawing shows us a situation that violates pretty much every law of physics on the books, and our brain perceives this logical oddity as amusing — a visual joke. The trick that makes Escher’s drawings intriguing is a geometric construction psychologists refer to as an “impossible figure,” a line-form suggesting a three-dimensional object that could never exist in our experience. Psychologists, including a team led by Catya von Károlyi of the University of Wisconsin-Eau Claire, have used such figures to study human cognition. When the team asked people to pick out impossible figures from similarly drawn illustrations that did not violate causality, they were surprised to discover that some people were faster at this than others. And most surprising of all, among those who were the fastest were those with dyslexia. © 2014 Scientific American