By Deborah Tuerkheimer Almost a decade into a 20-year prison sentence for murdering a baby in her care, 43-year-old Jennifer Del Prete was ordered freed on bond late last week. The ruling is one of a growing number that reflect skepticism on the part of judges, juries, and even prosecutors about criminal convictions based on the medical diagnosis of shaken baby syndrome. The case is also a critical turning point. The certainty that once surrounded shaken baby syndrome, or SBS, has been dissolving for years. The justice system is beginning to acknowledge this shift but should go further to re-examine and perhaps overturn more past convictions. Doctors once believed that three neurological symptoms—bleeding beneath the outer layer of membranes surrounding the brain (subdural hemorrhaging), bleeding in the retina, and brain swelling—always meant that a baby had been shaken. Because it was accepted that a baby with these three symptoms would show the effect of brain damage immediately, the “triad,” as it became known, was also used to establish the identity of the abuser—the last person with the baby. SBS was, in essence, a medical diagnosis of murder. Beginning in the 1990s, hundreds of cases were prosecuted based on this conception of SBS. The evidence of guilt was strikingly similar from case to case. This includes the Illinois prosecution of Jennifer Del Prete. In 2002, Del Prete was working at a small home day care in a Chicago suburb. One day, when she went to feed the 4-month-old baby in her care, she says she discovered the infant limp. Because the baby had the telltale triad of SBS symptoms, doctors were sure that Del Prete had shaken the baby to death. She denied it, and there were no witnesses. But based on the testimony of medical experts—primarily a pediatrician—she was convicted of murder in the first degree. © 2014 The Slate Group LLC.

Keyword: Brain Injury/Concussion; Development of the Brain
Link ID: 19568 - Posted: 05.04.2014

by Bethany Brookshire When I was a lab scientist working with mice, I spent hours controlling variables. I stood on precarious chairs to tape tarps over lights to get the light level perfectly right. I made one undergraduate who wore perfume to the lab for animal training wear the same perfume for a whole semester. I was so worried about the mice “recognizing” me over long, overlapping experiments that I did not change the scents of any of my personal care products for nine years. Many of these variables got reported in the methods sections of my papers. “All experiments conducted between 5:00 and 7:00 a.m. Maze dimensions: 4 inches wide, with walls 6 inches tall. Lighting held constant at 10 lux.” All of these variables are reported to allow other people to repeat my experiments, and hopefully get the same result. Now, a new study suggests that maybe I should have included another element in my methods section: “All mice exposed to the scent of a woman.” Jeffrey Mogil’s lab at McGill University in Montreal, Canada, reports April 28 in Nature Methods that mice respond differently to men and women, and that men in fact are a stressful influence. The results show that there’s yet another variable to control when doing sensitive mouse behavioral studies, a variable that could impact fields from pain to depression and beyond. Every department that does animal research has stories about particular experimenters. I recall hearing a story of a lab technician who could get results no one else could, because mice just loved her strawberry-scented hair conditioner. Another colleague told of one experimenter who was so good at handling rats that no one believed her anxiety results. Her rats were just so relaxed. And Mogil’s lab had its own story. In their lab, the presence of human experimenters seemed to stop mice from showing pain. © Society for Science & the Public 2000 - 2013

Keyword: Stress; Sexual Behavior
Link ID: 19567 - Posted: 05.04.2014

by Colin Barras Enough of the cheap jibes: Neanderthals may have been just as clever as modern humans. Anthropologists have already demolished the idea that Neanderthals were dumb brutes, and now a review of the archaeological record suggests they were our equals. Neanderthals were one of the most successful of all hominin species, occupying much of Europe and Asia. Their final demise about 40,000 years ago, shortly after Homo sapiens walked into their territory, is often put down to the superiority of our species. It's time to lay that idea to rest, say Paola Villa at the University of Colorado in Boulder and Wil Roebroeks at Leiden University in the Netherlands. Just as smart as you For instance, there is evidence that Homo sapiens could use fire to chemically transform natural materials into glue 70,000 years ago, but Neanderthals were performing similarly complex chemical syntheses at least 200,000 years ago. And although 70,000-year-old engraved ochre from South Africa is seen as evidence that our species had developed sophisticated symbolism and perhaps even language, similar artefacts have been found at 50,000-year-old Neanderthal sites in Spain. What's more, Neanderthals might have been able to talk. Late last year we learned that our extinct cousins had a hyoid, a small bone in the neck that plays a big role in speech, very like ours. Evidence has even emerged that Homo sapiens may have learned some skills by copying Neanderthals. Yet despite all of this evidence, the idea that Neanderthals were our inferiors still persists. © Copyright Reed Business Information Ltd.

Keyword: Evolution; Language
Link ID: 19566 - Posted: 05.04.2014

Humans stink, and it’s wonderful. A few whiffs of a pillow in the morning can revive memories of a lover. The sweaty stench of a gym puts us in the mood to exercise. Odors define us, yet the scientific zeitgeist is that we don’t communicate through pheromones—scents that influence behavior. A new study challenges that thinking, finding that scent can change whether we think someone is masculine or feminine. Humans carry more secretion and sweat glands in their skin than any other primate. Yet 70% of people lack a vomeronasal organ, a crescent-shaped bundle of neurons at the base of each nostril that allows a variety of species—from reptiles to nonprimate mammals—to pick up on pheromones. (If you’ve ever seen your cat huff something, he’s using this organ.) Still, scientists have continued to hunt for examples of pheromones that humans might sense. Two strong candidates are androstadienone (andro) and estratetraenol (estra). Men secrete andro in their sweat and semen, while estra is primarily found in female urine. Researchers have found hints that both trigger arousal—by improving moods and switching on the brain’s “urge” center, the hypothalamus—in the opposite sex. Yet to be true pheromones, these chemicals must shape how people view different genders. That’s exactly what they do, researchers from the Chinese Academy of Sciences in Beijing report online today in Current Biology. The team split men and women into groups of 24 and then had them watch virtual simulations of a human figure walking (see video). The head, pelvis, and major joints in each figure were replaced with moving dots. Subjects in prior studies had ranked the videos as being feminine or masculine. For instance, watch the figure on the far left, which was gauged as having a quintessential female strut. Notice a distinctive swagger in the “hip” dots and how they contrast with the flat gait of the “male” prototype all the way to the right. © 2014 American Association for the Advancement of Science

Keyword: Chemical Senses (Smell & Taste); Sexual Behavior
Link ID: 19565 - Posted: 05.03.2014

By Gabriella Rosen Kellerman By 1664, the year he published his most famous book of neuroanatomy, Cerebri Anatome, Dr. Thomas Willis was already renowned in Britain for saving lives. Fourteen years earlier, the corpse of executed murderer Anne Green had been delivered to Willis and some of his colleagues for autopsy. Upon opening the coffin—the story goes—the doctors heard a gasp. Ms. Green, they discovered, had been hanged but not executed. Thanks to the resuscitation efforts of Willis and his colleagues, Green survived, and was given a stay of execution. She died fifteen years later. The episode supposedly drew jealousy from Willis’s contemporaries, who could have had no idea just how many lives Willis’s work would one day save. Among the important discoveries included in Cerebri Anatome, considered the founding text of neurology, is the Circle of Willis, a map of the interconnecting arteries at the base of the brain. Such circular connections among arteries are called anastomoses. They enable blood to reach vital tissue along multiple routes so that when one is blocked, the blood has an alternative outlet. The Circle of Willis is perhaps most important because of its implications for stroke. Stroke, which is the third leading cause of death in this country, occurs when blood flow to the brain is disrupted. This can occur when an artery gets blocked with plaque or a clot (called an ischemic stroke) or when at artery bursts (called hemorrhagic stroke). Many of these problems, particularly the latter kind of stroke, occur in the Circle of Willis. © 2014 Scientific American

Keyword: Stroke
Link ID: 19564 - Posted: 05.03.2014

Fork-tailed drongos, glossy black African songbirds with ruby-colored eyes, are the avian kingdom’s masters of deception. They mimic the alarm calls of other species to scare animals away and then swipe their dupes’ dinner. But like the boy who cried wolf, drongos can raise the alarm once too often. Now, scientists have discovered that when one false alarm no longer works, the birds switch to another species’ warning cry, a tactic that usually does the trick. “The findings are astounding,” says John Marzluff, a wildlife biologist at the University of Washington, Seattle, who was not involved in the work. “Drongos are exceedingly deceptive; their vocabularies are immense; and they match their deception to both the target animal and [its] past response. This level of sophistication is incredible.” Since 2008, Tom Flower, an evolutionary biologist at the University of Cape Town, has followed drongos in the Kuruman River Reserve in the Kalahari Desert. He’s habituated and banded about 200 of the robin-sized birds, and, using food rewards, has trained individuals to come to him when he calls. After getting its snack, the drongo quickly returns to its natural behavior—catching insects and following other bird species or meerkats—while Flower tags along. Drongos also keep an eye out for raptors and other predators. When they spot one, they utter metallic alarm cries. Meerkats and pied babblers, a highly social bird, pay attention to the drongos and dash for cover when the drongos raise an alarm—just as they do when one of their own calls out a warning. Studies have shown that having drongos around benefits animals of other species, which don’t have to be as vigilant and can spend more time foraging. But there’s a trade-off: The drongos’ cries aren’t always honest. When a meerkat has caught a fat grub or gecko, a drongo is apt to change from trustworthy sentinel to wily deceiver. © 2014 American Association for the Advancement of Science.

Keyword: Animal Communication; Language
Link ID: 19563 - Posted: 05.03.2014

Brian Owens If you think you know what you just said, think again. People can be tricked into believing they have just said something they did not, researchers report this week. The dominant model of how speech works is that it is planned in advance — speakers begin with a conscious idea of exactly what they are going to say. But some researchers think that speech is not entirely planned, and that people know what they are saying in part through hearing themselves speak. So cognitive scientist Andreas Lind and his colleagues at Lund University in Sweden wanted to see what would happen if someone said one word, but heard themselves saying another. “If we use auditory feedback to compare what we say with a well-specified intention, then any mismatch should be quickly detected,” he says. “But if the feedback is instead a powerful factor in a dynamic, interpretative process, then the manipulation could go undetected.” In Lind’s experiment, participants took a Stroop test — in which a person is shown, for example, the word ‘red’ printed in blue and is asked to name the colour of the type (in this case, blue). During the test, participants heard their responses through headphones. The responses were recorded so that Lind could occasionally play back the wrong word, giving participants auditory feedback of their own voice saying something different from what they had just said. Lind chose the words ‘grey’ and ‘green’ (grå and grön in Swedish) to switch, as they sound similar but have different meanings. © 2014 Nature Publishing Group

Keyword: Language; Consciousness
Link ID: 19562 - Posted: 05.03.2014

A UBC neuroscientist says motherhood permanently alters the brain, exposing moms to different health risks than women without children. Liisa Galea, a professor in the university's psychology department, says some changes are temporary while others are permanent. The most obvious example is size. According to Galea, a mother's brain shrinks by up to eight per cent during pregnancy. While it bounces back about six months after birth, she notes the reaction could have repercussions. “Our research shows that, as a result of these transformations, mothers experience different cognitive abilities and health risks than women without children,” said Galea. And she warns that women who’ve borne children may even react to medication differently. “If mothers’ brains are different than other women’s brains, as our research finds, it means we must embrace greater personalization of medical care – not only for men versus women, but even among women with different life experiences,” she said. But that’s a challenge that may be insurmountable given that medical research studies at the animal model level have relied predominantly on the use of male rats. “Why would we assume that what works in a male rat automatically works in a female patient before testing it on a female rat?” questioned Galea. She claims one of the big failures of translational studies is that most fail to acknowledge how subjects’ gender, or other unique characteristics, like motherhood, plays a role. © CBC 2014

Keyword: Sexual Behavior; Hormones & Behavior
Link ID: 19561 - Posted: 05.03.2014

by Lisa Grossman Hasta la vista, nerve damage. Experiments with bullfrog nerves show that a Terminator-style liquid metal alloy could one day be placed in the body to help severed nerves reconnect. The alloy would stay in place until the nerve has healed, before being slurped back out with a syringe. The peripheral nervous system consists of nerves that carry electrical signals from the brain to the rest of the body. Because they aren't protected by the spine or the skull, peripheral nerves are more vulnerable to injuries than those in the central nervous system. Severed nerves can reconnect if treated quickly enough, but at a rate of just 1 millimetre per day. Also, existing methodsMovie Camera for grafting nerve ends back together have serious shortcomings. For instance, most existing scaffolds for grafts must ultimately be removed, requiring risky follow-up surgery. Even more worrisome, if the nerves don't pass signals to muscles during the healing process, the muscles can atrophy to the point where they never fully recover. Liu and his colleagues wondered if liquid metal could act as a backup system for damaged nerves, helping signals pass through a graft while the nerve healed. They used an alloy of gallium, indium and selenium, which is a very good electrical conductor. The alloy is liquid at room temperature, allowing it to be removed with a syringe when it's no longer needed. © Copyright Reed Business Information Ltd.

Keyword: Regeneration; Robotics
Link ID: 19560 - Posted: 05.03.2014

By Brian Palmer The Journal of Neuroscience recently published a study linking recreational marijuana use to subtle changes in brain structure. The researchers, led by Jodi Gilman of Massachusetts General Hospital, identified increased gray matter density in the left nucleus accumbens and some bordering areas. The study was fine, but the media coverage was abysmal. Reporters overstated the findings, mischaracterized the study, and failed to mention previous research done on pot smoking and health. Goldfish may not have a three-second memory, but some journalists seem to. When a new paper comes out, it’s often treated as the first ever and final word on the topic. There is a significant body of literature on the neurological and wider health effects of marijuana, and to ignore it when covering new studies seems to me a form of journalistic malpractice. A press release from the Society for Neuroscience trumpeted the Gilman study’s importance because it looked at casual users rather than regular pot smokers, who form the basis of most marijuana studies. That claim is dubious in the extreme. The subjects averaged 3.83 days of smoking and 11.2 total joints per week. Characterizing these people as casual pot smokers was a great media hook, but it defied common sense. Occasional users wondered if they’d done permanent damage, and parents were concerned that their teenagers might face profound neurological changes from experimenting with pot. Any reporter who read the study, however, should have known not to take that bait. Even by the standards of past medical studies, it’s a stretch to call these subjects casual pot smokers. © 2014 The Slate Group LLC.

Keyword: Drug Abuse
Link ID: 19559 - Posted: 05.03.2014

By Greg Miller As a journalist who writes about neuroscience, I’ve gotten a lot of super enthusiastic press releases touting a new breakthrough in using brain scans to read people’s minds. They usually come from a major university or a prestigious journal. They make it sound like a brave new future has suddenly arrived, a future in which brain scans advance the cause of truth and justice and help doctors communicate with patients whose minds are still active despite their paralyzed bodies. Amazing, right? Drop everything and write a story! Well, not so fast. Whenever I read these papers and talk to the scientists, I end up feeling conflicted. What they’ve done–so far, anyway–really doesn’t live up to what most people have in mind when they think about mind reading. Then again, the stuff they actually can do is pretty amazing. And they’re getting better at it, little by little. In pop culture, mind reading usually looks something like this: Somebody wears a goofy-looking cap with lots of wires and blinking lights while guys in white lab coats huddle around a monitor in another room to watch the movie that’s playing out in the person’s head, complete with cringe-inducing internal monologue. We are not there yet. “We can decode mental states to a degree,” said John-Dylan Haynes, a cognitive neuroscientist at Charité-Universitätsmedizin Berlin. “But we are far from a universal mind reading machine. For that you would need to be able to (a) take an arbitrary person, (b) decode arbitrary mental states and (c) do so without long calibration.” © 2014 Condé Nast.

Keyword: Brain imaging; Vision
Link ID: 19558 - Posted: 04.30.2014

Brian Owens Surveys of people's eating habits have suggested a link between fibre intake and weight loss, but exactly how fibre helps to regulate weight has been unclear. A study of mouse metabolism suggests that a product of fibre fermentation may be directly affecting the hypothalamus, a region of the brain involved in regulating appetite. People have long been told that a diet high in fibre can help to fight obesity, but how it does so has been unclear. “There has been lots of epidemiological information showing a relationship between fibre and obesity, but no one has been able to connect the epidemiological results with actual mechanisms,” says Jimmy Bell, a biochemist at Imperial College London who worked on the research, published today in Nature Communications1. Until now, a high-fibre diet was thought to help keep weight down by stimulating the release of appetite-suppressing hormones in the gut2, says Bell, but humans do not seem to show the same increase in these hormones that mice do. So Bell and his colleagues decided to look elsewhere. An obvious candidate, they thought, might be one of the products of fibre fermentation in the gut. In particular they focused on the short-chain fatty acid acetate, because it is the most abundant and is known to circulate throughout the bloodstream. They fed mice fibre labelled with carbon-13, which has an additional neutron from the more common carbon-12 that gives its nuclei a magnetic spin and therefore makes it easy to track as it progresses through the body's chemical reactions. The fibre was fermented as usual into acetate, which turned up not only in the gut, but also in the hypothalamus, a part of the brain known to be involved in regulating appetite. There, the researchers found, it was metabolized through the glutamine-glutamate cycle, which is involved in controlling the release of neurotransmitters associated with appetite control. The same model has been proposed for acetate metabolism after drinking alcohol. © 2014 Nature Publishing Group,

Keyword: Obesity
Link ID: 19557 - Posted: 04.30.2014

By Helen Briggs BBC News A mother's diet around the time of conception can permanently influence her baby's DNA, research suggests. Animal experiments show diet in pregnancy can switch genes on or off, but this is the first human evidence. The research followed women in rural Gambia, where seasonal climate leads to big differences in diet between rainy and dry periods. It emphasises the need for a well-balanced diet before conception and in pregnancy, says a UK/US team. Scientists followed 84 pregnant women who conceived at the peak of the rainy season, and about the same number who conceived at the peak of the dry season. Nutrient levels were measured in blood samples taken from the women; while the DNA of their babies was analysed two to eight months after birth. Lead scientist Dr Branwen Hennig, from the London School of Hygiene & Tropical Medicine, said it was the first demonstration in humans that a mother's nutrition at the time of conception can change how her child's genes will be interpreted for life. She told BBC News: "Our results have shown that maternal nutrition pre-conception and in early pregnancy is important and may have implications for health outcomes of the next generation. "Women should have a well-balanced food diet prior to conception and during pregnancy." BBC © 2014

Keyword: Epigenetics; Sexual Behavior
Link ID: 19556 - Posted: 04.30.2014

Guys, do you prefer more feminine faces? If so, chances are you grew up in a relatively healthy place. New research suggests that men raised in countries with higher average lifespans and lower child mortality more strongly prefer women with softer features than do men raised in less healthy nations. The finding bolsters the idea that years of human evolution have made men attracted to faces that could help them survive. Previous studies have found that women living in harsher conditions—such as communities with high homicide rates and low income—are more inclined to find more masculine men attractive. Urszula Marcinkowska, a biologist at the University of Turku in Finland, and her colleagues wanted to know whether culture also influenced males’ preferences for females, or whether men judged females in a more universal way. Using an online survey conducted in 16 different languages, the researchers presented 1972 heterosexual males between the ages of 18 and 24 from 28 different countries with 20 pairs of Caucasian female faces. Each pair contained one face with more feminine traits—such as larger eyes, fuller lips, and a less angular jaw—as well as a more androgynous face, with thinner lips and a wider chin. Participants were asked to select which face in each pair they found more sexually attractive. While men across all cultures generally preferred a more feminine face, the strength of that preference varied between countries. The difference couldn’t be explained by the ratio of men to women in a country, its gross national income, or the race of the participants, but it did correlate with the national health index of the men’s countries—a measure of overall well-being. Those from countries like Japan, with high national health index scores, chose the more feminine face more than three-quarters of the time, the authors report online today in Biology Letters. Men from countries such as Nepal, which has a lower health rating, selected the more feminine face in only slightly more than half of the cases, on average. © 2014 American Association for the Advancement of Science

Keyword: Sexual Behavior; Hormones & Behavior
Link ID: 19555 - Posted: 04.30.2014

THAT health and beauty are linked is not in doubt. But it comes as something of a surprise that who is perceived as beautiful depends not only on the health of the person in question but also on the average level of health in the place where she lives. This, though, is the conclusion of a study just published in Biology Letters by Urszula Marcinkowska of the University of Turku, in Finland, and her colleagues—for Ms Marcinkowska has found that men in healthy countries think women with the most feminine faces are the prettiest whilst those in unhealthy places prefer more masculine-looking ones. Ms Marcinkowska came to this conclusion by showing nearly 2,000 men from 28 countries various versions of the same female faces, modified to look less or more feminine, and thus reflect the effects of different levels of oestrogen and testosterone. Oestrogen promotes features, such as large eyes and full lips, that are characteristically feminine. Testosterone promotes masculine features, such as wide faces and strong chins. As the chart shows, the correlation is remarkable—and statistical analysis shows it is unconnected with a country’s wealth or its ratio of men to women and thus the amount of choice available to men. The cause, though, is unclear. Previous studies have shown that women with feminine features are more fertile. A man’s preference for them is thus likely to enhance his reproductive success. Ms Marcinkowska speculates that testosterone-induced behavioural characteristics like dominance, which might be expected to correlate with masculine-looking faces even in women (they certainly do in men), help in the competition for resources needed to sustain children once they are born. But why that should be particularly important in an unhealthy country is unclear.

Keyword: Sexual Behavior; Hormones & Behavior
Link ID: 19554 - Posted: 04.30.2014

by Bethany Brookshire When you are waiting with a friend to cross a busy intersection, car engines running, horns honking and the city humming all around you, your brain is busy processing all those sounds. Somehow, though, the human auditory system can filter out the extraneous noise and allow you to hear what your friend is telling you. But if you tried to ask your iPhone a question, Siri might have a tougher time. A new study shows how the mammalian brain can distinguish the signal from the noise. Brain cells in the primary auditory cortex can both turn down the noise and increase the gain on the signal. The results show how the brain processes sound in noisy environments, and might eventually help in the development of better voice recognition devices, including improvements to cochlear implants for those with hearing loss. Not to mention getting Siri to understand you on a chaotic street corner. Nima Mesgarani and colleagues at the University of Maryland in College Park were interested in how mammalian brains separate speech from background noise. Ferrets have an auditory system that is extremely similar to humans. So the researchers looked at the A1 area of the ferret cortex, which corresponds to our auditory A1 region. Equipped with carefully implanted electrodes, the alert ferrets listened to both ferret sounds and parts of human speech. The ferret sounds and speech were presented alone, against a background of white noise, against pink noise (noise with equal energy at all octaves that sounds lower in pitch than white noise) and against reverberation. Then they took the neural signals recorded from the electrodes and used a computer simulation to reconstruct the sounds the animal was hearing. In results published April 21 in Proceedings of the National Academy of Sciences, the researchers show the ferret brain is quite good at detecting both ferrets sounds and speech in all three noisy conditions. “We found that the noise is drastically decreased, as if the brain of the ferret filtered it out and recovered the cleaned speech,” Mesgarani says. © Society for Science & the Public 2000 - 2013.

Keyword: Attention; Hearing
Link ID: 19553 - Posted: 04.30.2014

Combining the estrogen hormone estriol with Copaxone, a drug indicated for the treatment of patients with relapsing forms of multiple sclerosis (MS), may improve symptoms in patients with the disorder, according to preliminary results from a clinical study of 158 patients with relapsing remitting multiple sclerosis (RRMS). The findings were presented today by Rhonda Voskuhl, M.D., from the University of California, Los Angeles, at the American Academy of Neurology Annual Meeting in Philadelphia. The study was funded by the National Institute of Neurological Disorders and Stroke (NINDS), part of the National Institutes of Health; and the National Multiple Sclerosis Society. “While these results are encouraging, the results of this Phase II study should be considered preliminary as a larger study would be needed to know whether benefits outweigh the risks for persons affected by MS. At present, we cannot recommend estrogen as part of standard therapy for MS. We encourage patients to talk with their doctors before making any changes to their treatment plans,” said Walter Koroshetz, M.D., deputy director of NINDS. MS is an autoimmune disorder in which immune cells break down myelin, a protective covering that wraps around nerve cells. Loss of myelin results in pain, movement and balance problems as well as changes in cognitive ability. RRMS is the most common form of the disorder. Patients with RRMS experience relapses, or flare-ups, of neurological symptoms, followed by recovery periods during which the symptoms improve.

Keyword: Multiple Sclerosis; Hormones & Behavior
Link ID: 19552 - Posted: 04.30.2014

Intelligence is hard to test, but one aspect of being smart is self-control, and a version of the old shell game that works for many species suggests that brain size is very important. When it comes to animal intelligence, says Evan MacLean, co-director of Duke University’s Canine Cognition Center, don’t ask which species is smarter. “Smarter at what?” is the right question. Many different tasks, requiring many different abilities, are given to animals to measure cognition. And narrowing the question takes on particular importance when the comparisons are across species. So Dr. MacLean, Brian Hare and Charles Nunn, also Duke scientists who study animal cognition, organized a worldwide effort by 58 scientists to test 36 species on a single ability: self-control. This capacity is thought to be part of thinking because it enables animals to override a strong, nonthinking impulse, and to solve a problem that requires some analysis of the situation in front of them. The testing program, which took several international meetings to arrange, and about seven years to complete, looked at two common tasks that are accepted ways to judge self-control. It then tried to correlate how well the animals did on the tests with other measures, like brain size, diet and the size of their normal social groups. Unsurprisingly, the great apes did very well. Dogs and baboons did pretty well. And squirrel monkeys, marmosets and some birds were among the worst performers. Surprisingly, absolute brain size turned out to be a much better predictor of success than relative brain size, which has been thought to be a good indication of intelligence. Social group size was not significant, but variety of diet was. The paper, published last week in the journal Proceedings of the National Academy of Sciences, is accompanied online by videos showing the animals doing what looks for all the world like the shell game in which a player has to guess where the pea is. © 2014 The New York Times Company

Keyword: Attention; Intelligence
Link ID: 19551 - Posted: 04.29.2014

Jeffrey Mogil’s students suspected there was something fishy going on with their experiments. They were injecting an irritant into the feet of mice to test their pain response, but the rodents didn’t seem to feel anything. “We thought there was something wrong with the injection,” says Mogil, a neuroscientist at McGill University in Montreal, Canada. The real culprit was far more surprising: The mice that didn’t feel pain had been handled by male students. Mogil’s group discovered that this gender distinction alone was enough to throw off their whole experiment—and likely influences the work of other researchers as well. “This is very important work with wide-ranging implications,” says M. Catherine Bushnell, a neuroscientist and the scientific director of the Division of Intramural Research at the National Center for Complementary and Alternative Medicine (NCCAM) in Bethesda, Maryland, who was not involved in the study. “Many people doing research have never thought of this.” Mogil has studied pain for 25 years. He’s long suspected that lab animals respond differently to the sensation when researchers are present. In 2007, his lab observed that mice spend less time licking a painful injection—a sign that they’re hurting—when a person is nearby, even if that “person” is a cardboard cutout of Paris Hilton. Other scientists began to wonder if their own data were biased by the same effect. “There were whisperings at meetings that this was confounding research results,” Mogil says. So he decided to take a closer look. In the new study, Mogil told the researchers in his lab to inject an inflammatory agent into the foot of a rat or mouse and then take a seat nearby and read a book. A video camera trained on the rodent’s face assessed the animal’s pain level, based on a 0- to 2-point “grimace scale” developed by the team. The results were mixed. Sometimes the animals showed pain when an experimenter was present, and sometimes they seemed just fine. So, on a hunch, Mogil and colleagues recrunched the data, this time controlling for whether a male or a female experimenter was present. “We were stunned by the results,” he says. © 2014 American Association for the Advancement of Science.

Keyword: Stress; Sexual Behavior
Link ID: 19550 - Posted: 04.29.2014

|By Christof Koch Quantum physicist Wolfgang Pauli expressed disdain for sloppy, nonsensical theories by denigrating them as “not even wrong,” meaning they were just empty conjectures that could be quickly dismissed. Unfortunately, many remarkably popular theories of consciousness are of this ilk—the idea, for instance, that our experiences can somehow be explained by the quantum theory that Pauli himself helped to formulate in the early 20th century. An even more far-fetched idea holds that consciousness emerged only a few thousand years ago, when humans realized that the voices in their head came not from the gods but from their own internal spoken narratives. Not every theory of consciousness, however, can be dismissed as just so much intellectual flapdoodle. During the past several decades, two distinct frameworks for explaining what consciousness is and how the brain produces it have emerged, each compelling in its own way. Each framework seeks to explain a vast storehouse of observations from both neurological patients and sophisticated laboratory experiments. One of these—the Integrated Information Theory—devised by psychiatrist and neuroscientist Giulio Tononi, which I have described before in these pages [see “Ubiquitous Minds”; Scientific American Mind, January/February 2014], uses a mathematical expression to represent conscious experience and then derives predictions about which circuits in the brain are essential to produce these experiences. [Full disclosure: I have worked with Tononi on this theory.] In contrast, the Global Workspace Model of consciousness moves in the opposite direction. Its starting point is behavioral experiments that manipulate conscious experience of people in a very controlled setting. It then seeks to identify the areas of the brain that underlie these experiences. © 2014 Scientific American

Keyword: Consciousness
Link ID: 19549 - Posted: 04.29.2014