Chapter 1. Biological Psychology: Scope and Outlook
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To expedite research on brain disorders, the National Institutes of Health is shifting from a limited funding role to coordinating a Web-based resource for sharing post-mortem brain tissue. Under a NIH NeuroBioBank initiative, five brain banks will begin collaborating in a tissue sharing network for the neuroscience community. “Instead of having to seek out brain tissue needed for a study from scattered repositories, researchers will have one-stop access to the specimens they need,” explained Thomas Insel, M.D., director of NIH’s National Institute of Mental Health (NIMH), one of three NIH institutes underwriting the project. “Such efficiency has become even more important with recent breakthrough technologies, such as CLARITY and resources such as BrainSpan that involve the use of human tissue.” Historically, NIH institutes have awarded investigator-initiated grants to support disease-specific brain bank activities. The NIH NeuroBioBank instead employs contracts, which affords the agency a more interactive role. Contracts totaling about $4.7 million for the 2013 fiscal year were awarded to brain banks at the Mount Sinai School of Medicine, New York City; Harvard University in Cambridge, Mass., the University of Miami; Sepulveda Research Corporation, Los Angeles; and the University of Pittsburgh. These brain and tissue repositories seek out and accept brain donations, store the tissue, and distribute it to qualified researchers seeking to understand the causes of – and identify treatments and cures for – brain disorders, such as schizophrenia, multiple sclerosis, depression, epilepsy, Down syndrome and autism.
Link ID: 18992 - Posted: 12.03.2013
By Scott Barry Kaufman One of the longest standing assumptions about the nature of human intelligence has just been seriously challenged. According to the traditional “investment” theory, intelligence can be classified into two main categories: fluid and crystallized. Differences in fluid intelligence are thought to reflect novel, on-the-spot reasoning, whereas differences in crystallized intelligence are thought to reflect previously acquired knowledge and skills. According to this theory, crystallized intelligence develops through the investment of fluid intelligence in a particular body of knowledge. As far as genetics is concerned, this story has a very clear prediction: In the general population– in which people differ in their educational experiences– the heritability of crystallized intelligence is expected to be lower than the heritability of fluid intelligence. This traditional theory assumes that fluid intelligence is heavily influenced by genes and relatively fixed, whereas crystallized intelligence is more heavily dependent on acquired skills and learning opportunities. But is this story really true? In a new study, Kees-Jan Kan and colleagues analyzed the results of 23 independent twin studies conducted with representative samples, yielding a total sample of 7,852 people. They investigated how heritability coefficients vary across specific cognitive abilities. Importantly, they assessed the “Cultural load” of various cognitive abilities by taking the average percentage of test items that were adjusted when the test was adapted for use in 13 different countries. © 2013 Scientific American
by NPR Staff Soon you'll be able to direct the path of a cockroach with a smartphone and the swipe of your finger. Greg Gage and his colleagues at Backyard Brains have developed a device called the that lets you control the path of an insect. It may make you squirm, but Gage says the device could inspire a new generation of neuroscientists. "The sharpest kids amongst us are probably going into other fields right now. And so we're kind of in the dark ages when it comes to neuroscience," he tells NPR's Arun Rath. He wants to get kids interested in neuroscience early enough to guide them toward that career path. And a cyborg cockroach might be the inspiration. "The neurons in the insects are very, very similar to the neurons inside the human brain," Gage says. "It's a beautiful way to just really understand what's happening inside your brain by looking at these little insects." The idea was spawned by a device the Backyard Brain-iacs developed called , which is capable of amplifying real living neurons. Insert a small wire into a cockroach's antennae, and you can hear the sound of actual neurons. "Lining the inside of the cockroach are these neurons that are picking up touch or vibration sensing, chemical sensing," Gage says. "They use it like a nose or a large tongue, their antennas, and they use it to sort of navigate the world. "So when you put a small wire inside of there, you can actually pick up the information as it's being encoded and being sent to the brain." With the RoboRoach device and smartphone app, you can interact with the antennae to influence the insect's behavior. ©2013 NPR
Link ID: 18819 - Posted: 10.22.2013
By MICHAEL WINES NEW HOLSTEIN, Wis. — Next to their white clapboard house on a rural road here, in long rows of cages set beneath the roofs of seven open-air sheds, Virginia and Gary Bonlander are raising 5,000 minks. Or were, anyway, until two Saturdays ago, when the police roused them from bed at 5 a.m. with a rap on their door. The Bonlanders woke one recent morning to find thousands of the creatures zipping across their lawn. Outside, 2,000 minks were scampering away — up to 50 top-quality, full-length and, suddenly, free-range mink coats. “The backyard was full of mink. The driveway was full of mink,” Mrs. Bonlander recalled a few days ago. “Then, pshew” — she made a whooshing sound — “they were gone.” And not only in Wisconsin, the mink-raising capital of the United States. After something of a hiatus, the animal rights movement has resumed a decades-old guerrilla war against the fur industry with a vengeance — and hints of more to come. In New Holstein; in Grand Meadow, Minn.; in Coalville, Utah; in Keota, Iowa; and four other states, activists say, eight dark-of-night raids on mink farms have liberated at least 7,700 of the critters — more than $770,000 worth of pelts — just since late July. That is more such raids than in the preceding three years combined. Two more raids in Ontario and British Columbia freed 1,300 other minks and foxes during the same period, according to the North American Animal Liberation Press Office, which bills itself as a conduit for messages from anonymous animal rights activists. “What we’re seeing now is unprecedented,” Peter Young, a Santa Cruz, Calif., activist who was imprisoned in 2005 for his role in raids on six mink ranches, said in a telephone interview. Though still an outspoken defender of the animal rights movement and mink-ranch raids, Mr. Young says he has no contact with those who raid fur farms or commit other illegal acts and, in fact, does not know who they are. © 2013 The New York Times Company
Keyword: Animal Rights
Link ID: 18797 - Posted: 10.17.2013
by Jack Flanagan Although dogs are said to be man's best friend, it doesn't mean they "get" us. At least, not like elephants seem to. Without any training, the giant herbivores can understand and follow our hand gestures – the first non-human animals known to be able to do so. Elephants have lived alongside humans for between 4000 and 8000 years. Despite their potential to be tamed, though, elephants have never been domesticated in the same way as dogs, cats and agricultural animals have. This hasn't prevented them from developing a number of human-like skills. In the wild, they are famously empathetic towards one another. In captivity, elephants have displayed a degree of self-awareness by being able to recognise themselves in a mirrorMovie Camera. Others have developed the teamwork necessary to coordinate and complete a task. In fact, one elephant has even learned some basic phrases in Korean – and another has been taught to paint by its parents. Arguably it was only a matter of time before they added another skill to their impressive repertoire. Hidden talent Pointing gestures are common enough among humans: from an early age babies naturally recognise the meaning behind them. We know that chimpanzees and even seals can do this too, but not without hours of training. It comes as a surprise, then, to discover that elephants can find hidden food once it is pointed out to them – without any prior lessons. © Copyright Reed Business Information Ltd.
By Justin Gregg Santino was a misanthrope with a habit of pelting tourists with rocks. As his reputation for mischief grew, he had to devise increasingly clever ways to ambush his wary victims. Santino learned to stash his rocks just out of sight and casually stand just a few feet from them in order to throw off suspicion. At the very moment that passersby were fooled into thinking that he meant them no harm, he grabbed his hidden projectiles and launched his attack. Santino was displaying an ability to learn from his past experiences and plan for future scenarios. This has long been a hallmark of human intelligence. But a recently published review paper by the psychologist Thomas Zentall from the University of Kentucky argues that this complex ability should no longer be considered unique to humans. Santino, you see, is not human. He’s a chimpanzee at Furuvik Zoo in Sweden. His crafty stone-throwing escapades have made him a global celebrity, and also caught the attention of researchers studying how animals, much like humans, might be able to plan their behavior. Santino is one of a handful of animals that scientists believe are showing a complex cognitive ability called episodic memory. Episodic memory is the ability to recall past events that one has the sense of having personally experienced. Unlike semantic memory, which involves recalling simple facts like “bee stings hurt,” episodic memory involves putting yourself at the heart of the memory; like remembering the time you swatted at a bee with a rolled up newspaper and it got angry and stung your hand. © 2013 Scientific American
Many people, I've heard talk, wonder what's going on inside Republican speaker John Boehner's brain. For cognitive neuroscientists, Boehner's brain is a case study. At the same time, others are frustrated with Democrat Harry Reid. The Senate Majority leader needs to take a tip from our founding fathers. Many of the intellectual giants who founded our democracy were both statesmen and scientists, and they applied the latest in scientific knowledge of their day to advantage in governing. The acoustics of the House of Representatives, now Statuary Hall, allowed John Quincy Adams and his comrades to eavesdrop on other members of congress conversing in whispers on the opposite side of the parabolic-shaped room. Senator Reid, in stark contrast, is still applying ancient techniques used when senators wore togas -- reason and argument -- and we all know how badly that turned out. The search for a path to compromise can be found in the latest research on the neurobiological basis of social behavior. Consider this new finding just published in the journal Brain Research. Oxytocin, a peptide produced in the hypothalamus of the brain and known to cement the strong bond between mother and child at birth, has been found to promote compromise in rivaling groups! This new research suggests that Congresswoman Nancy Pelosi could single-handedly end the Washington deadlock by spritzing a bit of oxytocin in her perfume and wafting it throughout the halls of congress. One can only imagine the loving effect this hormone would have on Senate Republican Ted Cruz, suddenly overwhelmed with an irresistible urge to bond with his colleagues, fawning for a cozy embrace like a babe cuddling in its mother's arms. And it is so simple! No stealthy spiking the opponent's coffee (or third martini at lunch) would be required, oxytocin works when it is inhaled through the nasal passages as an odorless vapor. © 2013 TheHuffingtonPost.com, Inc.
Link ID: 18761 - Posted: 10.08.2013
At the TEDx conference in Detroit last week, RoboRoach #12 scuttled across the exhibition floor, pursued not by an exterminator but by a gaggle of fascinated onlookers. Wearing a tiny backpack of microelectronics on its shell, the cockroach—a member of the Blaptica dubia species—zigzagged along the corridor in a twitchy fashion, its direction controlled by the brush of a finger against an iPhone touch screen (as seen in video above). RoboRoach #12 and its brethren are billed as a do-it-yourself neuroscience experiment that allows students to create their own “cyborg” insects. The roach was the main feature of the TEDx talk by Greg Gage and Tim Marzullo, co-founders of an educational company called Backyard Brains. After a summer Kickstarter campaign raised enough money to let them hone their insect creation, the pair used the Detroit presentation to show it off and announce that starting in November, the company will, for $99, begin shipping live cockroaches across the nation, accompanied by a microelectronic hardware and surgical kits geared toward students as young as 10 years old. That news, however, hasn’t been greeted warmly by everyone. Gage and Marzullo, both trained as neuroscientists and engineers, say that the purpose of the project is to spur a “neuro-revolution” by inspiring more kids to join the fields when they grow up, but some critics say the project is sending the wrong message. "They encourage amateurs to operate invasively on living organisms" and "encourage thinking of complex living organisms as mere machines or tools," says Michael Allen Fox, a professor of philosophy at Queen's University in Kingston, Canada. © 2013 American Association for the Advancement of Science
Keyword: Animal Rights
Link ID: 18755 - Posted: 10.08.2013
By John Horgan Last spring, I kicked up a kerfuffle by proposing that research on race and intelligence, given its potential for exacerbating discrimination, should be banned. Now Nature has expanded this debate with “Taboo Genetics.” The article “looks at four controversial areas of behavioral genetics”—intelligence, race, violence and sexuality—”to find out why each field has been a flashpoint, and whether there are sound scientific reasons for pursuing such studies.” Behavioral genetics has failed to produce robust evidence linking complex traits and disorders to specific genes. The essay provides a solid overview, including input from both defenders of behavioral genetics and critics. The author, Erika Check Hayden, quotes me saying that research on race and intelligence too often bolsters “racist ideas about the inferiority of certain groups, which plays into racist policies.” I only wish that Hayden had repeated my broader complaint against behavioral genetics, which attempts to explain human behavior in genetic terms. The field, which I’ve been following since the late 1980s, has a horrendous track record. My concerns about the potential for abuse of behavioral genetics are directly related to its history of widely publicized, erroneous claims. I like to call behavioral genetics “gene whiz science,” because “advances” so often conform to the same pattern. Researchers, or gene-whizzers, announce: There’s a gene that makes you gay! That makes you super-smart! That makes you believe in God! That makes you vote for Barney Frank! The media and the public collectively exclaim, “Gee whiz!” © 2013 Scientific American
Smart, successful, and well-connected: a good description of Albert Einstein … and his brain. The father of relativity theory didn’t live to see modern brain imaging techniques, but after his death his brain was sliced into sections and photographed. Now, scientists have used those cross-sectional photos to reveal a larger-than-average corpus callosum—the bundle of nerve fibers connecting the brain’s two hemispheres. Researchers measured the thickness of the famous noggin’s corpus callosum (the lighter-colored, downward-curving region at the center of each hemisphere, above) at various points along its length, and compared it to MRIs from 15 elderly men and 52 young, healthy ones. The thickness of Einstein’s corpus callosum was greater than the average for both the elderly and the young subjects, the team reported online last week in the journal Brain. The authors posit that in Einstein’s brain, more nerve fibers connected key regions such as the two sides of the prefrontal cortex, which are responsible for complex thought and decision-making. Combined with previous evidence that parts of the physicist’s brain were unusually large and intricately folded, the researchers suggest that this feature helps account for his extraordinary gifts. © 2013 American Association for the Advancement of Science
by Colin Barras SHAKEN, scorched and boiled in its own juices, this 4000-year-old human brain has been through a lot. It may look like nothing more than a bit of burnt log, but it is one of the oldest brains ever found. Its discovery, and the story now being pieced together of its owner's last hours, offers the tantalising prospect that archaeological remains could harbour more ancient brain specimens than thought. If that's the case, it potentially opens the way to studying the health of the brain in prehistoric times. Brain tissue is rich in enzymes that cause cells to break down rapidly after death, but this process can be halted if conditions are right. For instance, brain tissue has been found in the perfectly preserved body of an Inca child sacrificed 500 years ago. In this case, death occurred at the top of an Andean mountain where the body swiftly froze, preserving the brain. However, Seyitömer Höyük – the Bronze Age settlement in western Turkey where this brain was found – is not in the mountains. So how did brain tissue survive in four skeletons dug up there between 2006 and 2011? Meriç Altinoz at Haliç University in Istanbul, Turkey, who together with colleagues has been analysing the find, says the clues are in the ground. The skeletons were found burnt in a layer of sediment that also contained charred wooden objects. Given that the region is tectonically active, Altinoz speculates that an earthquake flattened the settlement and buried the people before fire spread through the rubble. © Copyright Reed Business Information Ltd.
Link ID: 18741 - Posted: 10.05.2013
Intelligence tests were first devised in the early twentieth century as a way to identify children who needed extra help in school. It was only later that the growing eugenics movement began to promote use of the tests to weed out the less intelligent and eliminate them from society, sparking a debate over the appropriateness of the study of intelligence that carries on to this day. But it was not the research that was problematic: it was the intended use of the results. As the News Feature on page 26 details, this history is never far from the minds of scientists who work in the most fraught areas of behavioural genetics. Although the ability to investigate the genetic factors that underlie the heritability of traits such as intelligence, violent behaviour, race and sexual orientation is new, arguments and attitudes about the significance of these traits are not. Scientists have a responsibility to do what they can to prevent abuses of their work, including the way it is communicated. Here are some pointers. First: be patient. Do not speculate about the possibility of finding certain results, or about the implications of those results, before your data have even been analysed. The BGI Cognitive Genomics group in Shenzhen, China, is studying thousands of people to find genes that underlie intelligence, but group members sparked a furore by predicting that studies such as theirs could one day let parents select embryos with genetic predispositions to high intelligence. Many other geneticists are sceptical that the project will even find genes linked to this trait. © 2013 Nature Publishing Group
Maggie Fox NBC News School officials in an area near New Orleans have shut off water fountains and stocked up on hand sanitizer this week after a brain-eating amoeba killed a 4-year-old boy and was found thriving in the local tap water system. Water officials say they are “shocking” the St. Bernard Parish system with chlorine to try to kill off the parasite and get the water back up to a safe standard. And while health experts say the water is perfectly safe to drink, some school officials are taking no chances. They’ve shut off water fountains until they are certain. Dr. Raoult Ratard, the Louisiana state epidemiologist, says the devastation wrought by Hurricane Katrina in 2005 may ultimately be to blame. Low-lying St. Bernard Parish, where the boy who died was infected while playing on a Slip ‘N Slide, was badly hit by the flooding that Katrina caused. “After Katrina, it almost completely depopulated,” Ratard told NBC News. “You have a lot of vacant lots and a lot of parts of the system where water is sitting there under the sun and not circulating.” That, says Ratard, provided a perfect opportunity for the amoeba to multiply. Without enough chlorine to kill them, they can spread. The Centers for Disease Control and Prevention said on Monday that it had found Naegleria fowleri in St. Bernard’s water supply – the first time it’s ever been found in U.S. tap water. The amoeba likes hot water and thrives in hot springs, warm lakes and rivers.
Link ID: 18662 - Posted: 09.18.2013
Karen Ravn It’s safe to say that wildlife biologist Lynn Rogers gets along better with the black bears in Minnesota than with the humans in the state’s Department of Natural Resources. Rogers, a popular bear researcher who has made numerous TV appearances, is engaged in quite a row with the department. At issue: should the department renew Rogers’ permit to study black bears? In June, the department said “no.” But trying to come between Rogers and his bears is a bit like trying to come between a mother bear and her cubs. He took the agency to court, and late last month, the parties came to a temporary agreement. Rogers can keep radio collars on the ten research bears that have them now, but he can’t keep live-streaming video on the Internet from his internationally popular den cams. His case will go back to court in six to nine months. Earlier this month, Rogers received a big boost from renowned chimpanzee researcher Jane Goodall, who wrote to Minnesota governor Mark Dayton praising Rogers and saying that it would be “a scientific tragedy” if his research were ended now. The department gave three reasons for not renewing Rogers’ permit: he hadn’t produced any peer-reviewed publications based on data collected over the past 14 years when he had a permit; his work was endangering the public; and he had engaged in unprofessional conduct. © 2013 Nature Publishing Group
Link ID: 18577 - Posted: 08.29.2013
Daniel Cressey A few chance encounters hundreds of metres underwater seem to have solved the long-standing mystery of what one squid species does with its unusual tentacles: it pretends they are fish to lure its prey into range. Until now, the deep-sea-dwelling squid Grimalditeuthis bonplandi had never been observed in the wild by researchers, and most of the knowledge about it came from partially digested specimens pulled from the stomachs of large fish and whales. Most squid have a pair of tentacles with hooks or suckers that they use to grasp food, but in this species the corresponding tentacles are thin, fragile things — and their function has puzzled squid researchers. Henk-Jan Hoving, a squid researcher at the Helmholtz Centre for Ocean Research in Kiel, Germany, and his team obtained videos of seven of these animals seen in the Atlantic and North Pacific. One of the observations came from an expedition run by the Monterey Bay Aquarium Research Institute in Moss Landing, California, and the other videos were made by commercial remotely-operated submersibles used by the oil and gas industry, and later supplied to Hoving and his team. Hoving and his team saw the squid move the ends of their unique appendages, known as tentacle clubs, in a way that “really looked like a small fish or squid”, he says. They describe their observations in Proceedings of the Royal Society B1. The movement of these tentacles attracts the crustaceans and other cephalopods that G. bonplandi eats. Thinking they are going to get dinner, the prey species move towards the flapping arms, only to be eaten themselves. © 2013 Nature Publishing Group
By Harvey Black The intelligence of the corvid family—a group of birds that includes crows, ravens, magpies, rooks and jackdaws—rivals that of apes and dolphins. Recent studies are revealing impressive details about crows' social reasoning, offering hints about how our own interpersonal intelligence may have evolved. One recent focus has been on how these birds respond to the sight of human faces. For example, crows take to the skies more quickly when an approaching person looks directly at them, as opposed to when an individual nears with an averted gaze, according to a report by biologist Barbara Clucas of Humboldt State University and her colleagues in the April issue of Ethology. The researchers walked toward groups of crows in three locations in the Seattle area, with their eyes either on the birds or on some point in the distance. The crows scattered earlier when the approaching person was looking at them, unlike other animals that avoid people no matter what a person is doing. Clucas speculates that ignoring a human with an averted gaze is a learned adaptation to life in the big city. Indeed, many studies have shown that crows are able to learn safety behaviors from one another. For example, John Marzluff of the University of Washington (who co-authored the aforementioned paper with Clucas) used masked researchers to test the learning abilities of crows. He and his colleagues ventured into Seattle parks wearing one of two kinds of masks. The people wearing one kind of mask trapped birds; the others simply walked by. Five years later the scientists returned to the parks with their masks. The birds present at the original trapping remembered which masks corresponded to capturing—and they passed this information to their young and other crows. All the crows responded to the sight of a researcher wearing a trapping mask by immediately mobbing the individual and shrieking. © 2013 Scientific American
By April Neale An innovative two-part series, "Brains on Trial with Alan Alda," airing Wednesday, September 11 and 18, 2013, 10-11 p.m. on PBS (check local listings), explores how the growing ability to separate truth from lies, even decode people’s thoughts and memories, may radically affect how criminal trials are conducted in the future. As brain scanning techniques advance, their influence in criminal cases is becoming critically important. Brains on Trial centers around the trial of a fictional crime: a robbery staged in a convenience store that has been filmed by the store’s security cameras. A teenager stands accused of the attempted murder of the store clerk’s wife who was shot during the crime. While the crime is fictional, the trial is conducted before a real federal judge and argued by real practicing attorneys. The program is divided into two-parts: the first hour examines the guilt phase of the trial concluding with the jury’s verdict; the second hour looks at the sentencing phase, when arguments for and against a severe sentence are heard. As the trial unfolds, Alda visits with neuroscientists whose research has already influenced some Supreme Court decisions, as well as Duke University law professor Nita Farahany, a member of the Presidential Commission for the Study of Bioethical Issues. On these visits, neuroscientists show how functional MRIs and other brain scanning techniques are exploring lie detection, facial recognition, memory decoding, racial bias, brain maturity, intention, and even emotions. The research Alda discovers is at the center of a controversy as to how this rapidly expanding ability to peer into people’s minds and decode their thoughts and feelings could – or should – affect trials like the one presented in the program. As DNA evidence has played a major role in exonerating innocent prisoners, Brains on Trial asks if neuroscience can make the criminal justice system more just.
Link ID: 18527 - Posted: 08.20.2013
By D. D. GUTTENPLAN LONDON — With its battered desks, fluorescent lights and interactive whiteboard showing an odd creature that, depending on how you look at it, could be either a duck or a rabbit, this could be a class in any university philosophy department. But this is a class with a difference. It is the Maudsley Philosophy Group, a seminar that meets regularly on the grounds of the Maudsley Hospital, Britain’s largest mental health teaching hospital, which is affiliated with the Institute of Psychiatry at King’s College London. Participants at the last session included psychiatrists, psychologists, philosophers and an actor who had just finished working as a chaplain in a locked men’s ward at the hospital and who was about to organize a storytelling group there. “We started out as a reading group for trainee psychiatrists,” said Gareth S. Owen, a researcher at the Institute of Psychiatry who co-founded the group in 2002. “Then, gradually, we developed and started inviting philosophers — at first it was quite low key. We would talk about our clinical experiences and then they would relate those experiences to their way of thinking.” Robert Harland, another co-founder of the group, said he had known Dr. Owen since they “cut up a corpse together at medical school.” “The analytic philosophers brought a real clarity to our discussions,” Dr. Harland said. “We were looking at various models to help us understand what we were doing as psychiatrists. “There is lots of applied science now in psychiatry: neuroimaging, genetics, epidemiology. But they don’t have much to say about sitting with a patient and trying to understand that person’s experiences.” © 2013 The New York Times Company
By Neuroskeptic Back in April a paper came out in Nature Reviews Neuroscience that shocked many: Katherine Button et al’s Power failure: why small sample size undermines the reliability of neuroscience It didn’t shock me, though, skeptic that I am: I had long suspected that much of neuroscience (and science in general) is underpowered – that is, that our sample sizes are too small to give us an acceptable chance of detecting the signals that we claim to be able to isolate out of the noise. In fact, I was so unsurprised by Button et al that I didn’t even read it, let alone write about it, even though the authors list included such neuro-blog favorites as John Ionaddis, Marcus Munafo and Brian Nosek (I try to avoid obvious favouritism, you see). However this week I took a belated look at the paper, and I noticed something interesting. Button et al took 49 meta-analyses and calculated the median observed statistical power of the studies in each analysis. The headline finding was that average power is small. I was curious to know why it was small. So I correlated the study characteristics (sample size and observed effect size) with the median power of the studies. I found that median power in a given meta-analysis was not correlated with the median sample size of those studies (d on the left, RR on the right):
Link ID: 18487 - Posted: 08.12.2013
Daniel Cressey Killing research animals is one of the most unpleasant tasks in science, and it is imperative to do it as humanely as possible. But researchers who study animal welfare and euthanasia are growing increasingly concerned that widely used techniques are not the least painful and least stressful available. This week, experts from across the world will gather in Newcastle upon Tyne, UK, to debate the evidence and try to reach a consensus. “There are lots of assumptions made about the humaneness of various techniques for euthanizing animals,” says Penny Hawkins, deputy head of the research animals department at the Royal Society for the Prevention of Cruelty to Animals, a charity based in Southwater, UK. “Sometimes an animal might not appear to be suffering, but might be conscious and suffering.” Much of the debate centres on rodents, which make up the vast majority of research animals. Current techniques for killing them include inhalation methods — such as chambers that fill with carbon dioxide or anaesthetic gases — and injecting barbiturates. Physical methods include cervical dislocation (breaking of the neck), or decapitation with specialist rodent guillotines (see ‘Methods used to kill lab rats’). Experts hotly debate which method is preferable. The most-discussed question at the meeting is likely to be about the use of CO2. © 2013 Nature Publishing Group
Keyword: Animal Rights
Link ID: 18469 - Posted: 08.07.2013