By Ann Gibbons From the moment in 2013 when paleoanthropologist Lee Berger posted a plea on Facebook, Twitter, and LinkedIn for “tiny and small, specialised cavers and spelunkers with excellent archaeological, palaeontological and excavation skills,” some experts began grumbling that the excavation of a mysterious hominin in the Rising Star Cave in South Africa was more of a media circus than a serious scientific expedition. Daily blogs recorded the dangerous maneuvers of “underground astronauts” who squeezed through a long, narrow chute to drop 30 meters into a fossil-filled cavern, while Berger, who is based at the University of the Witwatersrand in Johannesburg, South Africa, became the “voice from the cave” in radio interviews. When it came time to analyze the fossils, Berger put out a call for applications from “early career scientists” to study them at a workshop in Johannesburg in March 2014. Handing over much of the analysis of such potentially important specimens to inexperienced researchers didn’t inspire confidence among Berger’s colleagues either, though it did win him the nickname Mr. Paleodemocracy. Many thought the expedition “had more hype than substance,” paleoanthropologist Chris Stringer of the Natural History Museum in London writes in a commentary accompanying the fossils’ official presentation this week in the journal eLIFE. But the substance has now been unveiled, and few dispute that the findings are impressive. In their report, Berger and his team describe 1550 fossils representing more than 15 ancient members of a strange new kind of hominin, which they named Homo naledi. (Naledi means “star” in the Sotho language spoken in the region of the cave.) © 2015 American Association for the Advancement of Science.

Keyword: Evolution
Link ID: 21392 - Posted: 09.10.2015

By Nicholas Bakalar Being obese at age 50 may be tied to an increased risk of developing Alzheimer’s disease at a younger age. Previous studies have shown that being overweight at midlife is associated with an increased risk of developing Alzheimer’s. Now researchers have found that it also predicts occurrence at a younger age. Scientists studied 1,394 cognitively normal people, average age around 60, following them for an average of 14 years. During the study, 142 developed Alzheimer’s. After controlling for age, race, level of education and cardiovascular risk factors, they found that each unit increase in B.M.I., or body mass index, at age 50 was associated with a 6.7-month decrease in the age of onset of Alzheimer’s. The study, in Molecular Psychiatry, also found an association of higher B.M.I. with larger deposits of neurofibrillary tangles on autopsy, one of the characteristics of brain damage in Alzheimer’s disease. “Age of onset is not as well studied as risk,” said the senior author, Dr. Madhav Thambisetty, a neurologist at the National Institute on Aging. “As we try to cure Alzheimer’s disease, we also want to delay the onset of symptoms. Until we know what factors accelerate onset, we won’t be able to test any potential interventions. And that is perhaps as important as the search for treatment.” © 2015 The New York Times Company

Keyword: Obesity; Alzheimers
Link ID: 21391 - Posted: 09.10.2015

By Steve Mirsky It's nice to know that the great man we celebrate in this special issue had a warm sense of humor. For example, in 1943 Albert Einstein received a letter from a junior high school student who mentioned that her math class was challenging. He wrote back, “Do not worry about your difficulties in mathematics; I can assure you that mine are still greater.” Today we know that his sentiment could also have been directed at crows, which are better at math than those members of various congressional committees that deal with science who refuse to acknowledge that global temperatures keep getting higher. Studies show that crows can easily discriminate between a group of, say, three objects and another containing nine. They have more trouble telling apart groups that are almost the same size, but unlike the aforementioned committee members, at least they're trying. A study in the Proceedings of the National Academy of Sciences USA finds that the brain of a crow has nerve cells that specialize in determining numbers—a method quite similar to what goes on in our primate brain. Human and crow brains are substantially different in size and organization, but convergent evolution seems to have decided that this kind of neuron-controlled numeracy is a good system. (Crows are probably unaware of evolution, which is excusable. Some members of various congressional committees that deal with science pad their reactionary résumés by not accepting evolution, which is astonishing.) © 2015 Scientific American

Keyword: Intelligence; Attention
Link ID: 21390 - Posted: 09.09.2015

By Susan Milius The larger Pacific striped octopus hunts shrimp using a strategy worthy of a schoolyard prank. And that’s not the only oddity about the species. It’s only the second octopus known with females that prolong motherhood, instead of dying after weeks of all-out coddling a single brood. But what everyone wants to talk about, researchers who study the species have found, is beak-to-beak mating. Before writhing, wrestling videos of the larger Pacific striped octopus (nicknamed LPSO), biologists knew of two forms of eight-armed sex. Some species mate at a distance, says Roy Caldwell of the University of California, Berkeley. The male extends one arm, always the same one, toward the female and up under her mantle. A travel-ready package of sperm emerges onto his skin and settles into a specialized groove on his mating arm. Waves of arm flexing resembling mammal intestinal motions nudge the packet toward one of two openings to her reproductive tracts. “It’s a messy way of reproducing,” Caldwell says. A lot of sperm packets “are wasted and go floating off.” Distance mating has other challenges. In an Indonesian octopus species, Caldwell’s former student Christine Huffard of the Monterey Bay Aquarium Research Institute discovered males hunkered in their dens sending an arm across the seafloor into the den of the female next door. On occasion, such females leave their dens on some octopus errand, dragging the male along by his mating arm. © Society for Science & the Public 2000 - 2015.

Keyword: Sexual Behavior
Link ID: 21389 - Posted: 09.09.2015

By Emily Chung, Whadd'ya at? Ow ya goin'? If you were at a picnic with a bunch of Newfoundlanders or Australians, those are the greetings you might fling around. Similarly, scientists who eavesdrop on sperm whales – Moby Dick's species — have found they also have distinct "dialects." And a new study suggests like human dialects, they arise through cultural learning. "Cultural transmission seems key to the partitioning of sperm whales into… clans," the researchers wrote in a paper published today in the journal Nature Communications. Sperm whales live around the world, mainly in deeper waters far offshore. The solitary males live in colder areas, and roam in Canadian waters in areas where the ocean depth is more than 1000 metres, says Mauricio Cantor, the Dalhousie University PhD. student who led the new study with Hal Whitehead, a Dalhousie biology professor. The females live in warmer, more southern waters, in loose family groups of around seven to 12 whales – sisters, aunts, grandmothers, cousins, and the occasional unrelated friend and their calves. Sometimes, they meet up with other families for gatherings of up to 200 whales, similar to human picnics or festivals. These can last from a few hours to a few days. The whales that gather in these groups, called clans, have distinct "dialects" of patterns of clicks called codas that are distinct from the clicks they use in echolocation when they're hunting for food. They use codas talk to each other when they surface between dives. ©2015 CBC/Radio-Canada.

Keyword: Language; Evolution
Link ID: 21388 - Posted: 09.09.2015

By Bruce Bower Lemurs don’t yawn in the face of danger. They wait a few minutes after perils have passed before breaking into breathy mouth gapes. Lemurs in a southern Madagascar reserve yawned frequently within 10 minutes of fighting with other lemurs, surviving attacks by predatory birds and coming close to snakes, tourists or other potential dangers, primatologist Elisabetta Palagi of the University of Pisa in Italy and her colleagues report August 28 in the American Journal of Primatology. Lemurs largely stopped yawning after that brief outburst. This pattern held for 13 ring-tailed lemurs and 15 Verreaux’s sifakas tracked daily for three months in 2011. Recurring dangers that lemurs learn to escape or avoid elicit moderate, brief anxiety, the researchers suspect. Yawning amps up as animals rapidly return to calmness, much as it increases when lemurs take rest breaks during the day, Palagi’s team says. Many physiological and social forces contribute to yawning, they add. Citations A. Zannella et al. Testing yawning hypotheses in wild populations of two strepsirrhine species: Propithecus verreauxi and Lemur catta. American Journal of Primatology. Published August 28, 2015. doi:10.1002/ajp.22459. © Society for Science & the Public 2000 - 2015.

Keyword: Emotions
Link ID: 21387 - Posted: 09.09.2015

Mo Costandi In an infamous set of experiments performed in the 1960s, psychologist Walter Mischel sat pre-school kids at a table, one by one, and placed a sweet treat – a small marshmallow, a biscuit, or a pretzel – in front of them. Each of the young participants was told that they would be left alone in the room, and that if they could resist the temptation to eat the sweet on the table in front of them, they would be rewarded with more sweets when the experimenter returned. The so-called Marshmallow Test was designed to test self-control and delayed gratification. Mischel and his colleagues tracked some of the children as they grew up, and then claimed that those who managed to hold out for longer in the original experiment performed better at school, and went on to become more successful in life, than those who couldn’t resist the temptation to eat the treat before the researcher returned to the room. The ability to exercise willpower and inhibit impulsive behaviours is considered to be a core feature of the brain’s executive functions, a set of neural processes - including attention, reasoning, and working memory - which regulate our behaviour and thoughts, and enable us to adapt them according to the changing demands of the task at hand. Executive function is a rather vague term, and we still don’t know much about its underlying bran mechanisms, or about how different components of this control system are related to one another. New research shows that self-control and memory share, and compete with each other for, the same brain mechanisms, such that exercising willpower saps these common resources and impairs our ability to encode memories. © 2015 Guardian News and Media Limited

Keyword: Attention; Learning & Memory
Link ID: 21386 - Posted: 09.08.2015

A particular region of the brain may drive smoking addiction, say scientists who found stroke survivors with damage to their insular cortex more easily kicked the habit. They studied 156 stroke patients with different patterns of brain injury. More of those with insular cortex damage successfully gave up smoking and reported fewer withdrawal symptoms than the other stroke patients. Experts say targeting this brain area may help other smokers quit. Most stop smoking medicines currently on the market work by blocking the brain's reward pathways in response to nicotine. And patches and gums aim to lessen cravings by supplying a controlled dose of nicotine as the person weans themselves off tobacco. But post-graduate researcher Amir Abdolahi and colleagues believe the insular cortex could be a valuable new target for quit smoking aids. Therapies that could hone in on this area of the brain and disrupt its role in addiction, potentially with new drugs or other techniques such as deep brain stimulation or transcranial magnetic stimulation, should be explored, they say. "Much more research is needed in order for us to more fully understand the underlying mechanism and specific role of the insular cortex, but it is clear that something is going on in this part of the brain that is influencing addiction," Mr Abdolahi said. The research findings are published in two medical journals - Addiction and Addictive Behaviors. The patients in the study were smokers who had been admitted to hospital because of a stroke. Medical scans revealed that 38 of them had suffered damage to the insular cortex, while the remaining 118 had damage to other parts of the brain. All of the patients were encouraged by their doctor to quit smoking. © 2015 BBC.

Keyword: Drug Abuse
Link ID: 21385 - Posted: 09.08.2015

By Michael Balter If you find yourself along the Atlantic coastal border between Spain and France, here are some phrases that might come in handy: Urte askotarako! (“Pleased to meet you!”), Eskerrik asko! (“Thank you!”), and Non daude komunak? (“Where is the toilet?”). Welcome to Basque Country, where many people speak a musical language that has no known relationship to any other tongue. Many researchers have assumed that Basque must represent a “relic language” spoken by the hunter-gatherers who occupied Western Europe before farmers moved in about 7500 years ago. But a new study contradicts that idea and concludes that the Basques are descended from a group of those early farmers that kept to itself as later waves of migration swept through Europe. The great majority of Europeans speak languages belonging to the Indo-European family, which includes such diverse tongues as German, Greek, Spanish, and French; a smaller number speak Uralic languages like Finnish, Hungarian, and Estonian. But Basque stands truly alone; what linguists call a “language isolate.” This uniqueness is a source of pride among the nearly 700,000 Basque speakers, some of whom have called for the creation of an independent nation separate from Spain and France. For scientists, however, Basque is a major unsolved mystery. In the 19th century, some anthropologists claimed that Basques had differently shaped skulls than other Europeans. Yet although that racial idea had been discredited by the 20th century, researchers have been able to show that the Basques have a striking number of genetic differences that set them apart from other Europeans. Variations in their immune cells and proteins include a higher-than-normal frequency of Rh-negative blood types, for example. Those findings led to the hypothesis that the Basques descended from early hunter-gatherers who had somehow avoided being genetically overwhelmed when farming spread into Europe from the Near East. But some recent studies have questioned just how genetically distinct the Basques really are. © 2015 American Association for the Advancement of Science.

Keyword: Language
Link ID: 21384 - Posted: 09.08.2015

By Melinda Wenner Moyer A worrisome new study caught my eye last week as I perused the website of the journal Pediatrics. It was titled “Cognition and Brain Structure Following Early Childhood Surgery With Anesthesia.” Considering that my now 4-year-old underwent general anesthesia for a minor procedure when he was 2 and that my 14-month-old may be a candidate for ear tube surgery, my interest was immediately piqued. I clicked through and came face to face with a whole lot of yuck. The first sentence alone made me gasp: “Anesthetics induce widespread cell death, permanent neuronal deletion, and neurocognitive impairment in immature animals, raising substantial concerns about similar effects occurring in young children.” Wait, so anesthesia causes brain damage? Why didn’t anyone tell me? I thought. Obviously, I needed to know more. Considering that 6 million American children—including 1.5 million babies under the age of 1—undergo general anesthesia each year, this seemed like a pretty serious issue to delve into. Twenty studies and several phone calls later, I’m feeling a lot better about my kids’ brains. There are still many things scientists don’t know about how anesthesia affects the nervous system, in part because they can’t ethically do the types of experiments that would provide clear answers, like unnecessarily exposing kids to anesthesia. But based on the research that does exist, there’s really no need for parents to freak out. If “going under” has an effect on the developing brain, it’s likely to be very small. Even Andreas Loepke, the pediatric anesthesiologist at Cincinnati Children’s Hospital Medical Center who co-authored the Pediatrics paper, was reassuring to me over the phone. “These are theoretical concerns,” he said. © 2015 The Slate Group LLC.

Keyword: Development of the Brain; Drug Abuse
Link ID: 21383 - Posted: 09.08.2015

Erin Wayman Nose picking isn’t a mark of distinction among people — but it is among monkeys. For the first time, researchers have reported a wild capuchin monkey using a tool to pick its nose and teeth. The monkey was caught in the act last year by Michael Haslam of the University of Oxford. For about five minutes, an adult female bearded capuchin (Sapajus libidinosus) in northeastern Brazil repeatedly inserted a twig or stem into its nostril, usually inducing a sneeze. The monkey also rubbed sticks back and forth against the base of its teeth, probably to dislodge debris, Haslam and Oxford colleague Tiago Falótico report in the July Primates. After picking its nose or teeth, the monkey often licked the tool tip, perhaps to wipe the stick clean. Bearded capuchins are quite handy, brandishing rocks to crack open nuts (SN Online: 4/30/15) and sticks to retrieve insects from crevices or to collect honey. But until now, no one had seen a wild capuchin use a tool as a nasal probe or toothpick. M. Haslam and T. Falótico. Nasal probe and toothpick tool use by a wild female bearded capuchin (Sapajus libidinosus). Primates. Vol. 56, July 2015, p. 211. doi: 10.1007/s10329-015-0470-6. © Society for Science & the Public 2000 - 2015

Keyword: Evolution
Link ID: 21382 - Posted: 09.08.2015

By Amy Ellis Nutt There may finally be an explanation for why men are often less verbally adept than women at expressing themselves. It's the testosterone. Scientists have long known that language development is different between boys and girls. But in scanning the brains of 18 individuals before and after undergoing hormone treatment for female-to-male sex reassignment, Austrian and Dutch researchers found evidence of specific brain structure differences. In particular, they found two areas in the left hemispheres of the transgender men that lost gray matter volume during high-testosterone treatment over a period of four weeks: Broca's area, which is involved in the production of language, and Wernicke's area, which processes language. All of which suggests, according to the study, which was presented this week at the European College of Neuropsychopharmacology Congress, why verbal abilities are often stronger in women than men. "In more general terms, these findings may suggest that a genuine difference between the brains of women and men is substantially attributable to the effects of circulating hormones," said one of the researchers at the conference, Rupert Lanzenberger from Vienna. "Moreover, the hormonal influence on human brain structure goes beyond the early developmental phase and is still present in adulthood." Previous research has shown that higher testosterone is linked to smaller vocabulary in children and also that verbal fluency skills seemed to decrease after female-to-male sex reassignment testosterone treatment.

Keyword: Language; Sexual Behavior
Link ID: 21381 - Posted: 09.03.2015

Christopher Joyce Ornithologist Arthur Allen of the Cornell Lab or Ornithology was a pioneer, hauling balky recording gear into the wilderness in the 1940s, and actually cutting acetate records of bird song on-site. Let's fast forward 45 years, and talk to Ted Parker, who inherited Allen's gift for recording birds and but added a twist. "Up here in the canopy, these are the hardest birds to detect," he told an NPR Radio Expeditions team in 1991 in the Bolivian rain forest. Parker was an ornithologist with Conservation International who spent months at a time in the tropics, lugging around a portable tape recorder. His skill in using his ears to investigate the world was legendary. "My parents bought me records of bird recordings that were made by people at Cornell," Parker tells the NPR team in 1991. "I spent hours moving the needle back and forth, and back and forth, and my mother would say, 'You are going to destroy the record player.' " Some called Parker the Mozart of ornithology. He'd memorized the sounds of more than 4,000 bird species. He used this knowledge and his tape recorder to quickly take an extensive and detailed census of birds in the tropics. "These birds spend all their time in that foliage that's 130 to 140 feet above the ground," Parker explains on the tape. "And if you don't know their voices, there's no way you could come to a place like this and come up with a good list of canopy species." © 2015 NPR

Keyword: Animal Communication; Language
Link ID: 21380 - Posted: 09.03.2015

By Olivia Campbell Leave it to childbirth to cause a woman who’s never felt pain in her life to now experience persistent discomfort. When a 37-year-old woman with a condition known as congenital insensitivity to pain gave birth, her labor was as painless as expected. But during the delivery, she sustained pelvic fractures and an epidural hematoma that impinged on a nerve in her lower spine. Since then, she has added an unfortunate variety of words to her vocabulary: Her hips “hurt” and “ache;” she feels a “continuous buzzing in both legs and a vice-like squeezing in the pelvis.” When resting, she is left with “tingling” and “electric shocks.” She now has headaches, backaches, period pains, and stomach cramps; and even describes “the sting” of a graze and “the sharpness” of an exposed gum. According to doctors who treated her, the woman's sensitivity to pain -- tested on the tops of her feet -- is 10 times higher than it was before she gave birth. Congenital insensitivity to pain is an incredibly rare genetic disorder — there are only 20 recorded cases — that causes individuals to be totally unaware of pain. Co-author of the paper Michael Lee explained how pain pathways start with specialized nerves, called nociceptors, that sense damaging temperatures or pressure and then fire off signals to the brain. Those signals make us feel pain to prevent further damage. In people with CIP, a defective gene prevents these signals from going through. But pain can also arise when nociceptors or nerves are damaged, as was the case when this woman’s lumbar nerve was pinched during childbirth.

Keyword: Pain & Touch
Link ID: 21379 - Posted: 09.03.2015

In 1938, an Austrian pediatrician named Hans Asperger gave the first public talk on autism in history. Asperger was speaking to an audience of Nazis, and he feared that his patients — children who fell onto what we now call the autism spectrum — were in danger of being sent to Nazi extermination camps. As Asperger spoke, he highlighted his "most promising" patients, a notion that would stick with the autistic spectrum for decades to come. "That is where the idea of so-called high-functioning versus low-functioning autistic people comes from really — it comes from Asperger's attempt to save the lives of the children in his clinic," science writer Steve Silberman tells Fresh Air's Terry Gross. Silberman chronicles the history of autism and examines some of the myths surrounding our current understanding of the condition in his new book, NeuroTribes. Along the way, he revisits Asperger's calculated efforts to save his patients. Steve Silberman's articles have been published in Wired, The New Yorker, Nature and Salon. Silberman shies away from using the terms high-functioning and low-functioning, because "both of those terms can be off base," he says. But he praises Asperger's courage in speaking to the Nazis. "I would literally weep while I was writing that chapter," he says. NeuroTribes also explores how a 1987 expansion of the medical definition of autism (which was previously much narrower and led to less frequent diagnoses) contributed to the perception that there was an autism epidemic. © 2015 NPR

Keyword: Autism
Link ID: 21378 - Posted: 09.03.2015

By Jennifer Couzin-Frankel Some rare diseases pull researchers in and don’t let them go, and the unusual bone condition called fibrodysplasia ossificans progressiva (FOP) has long had its hooks in Aris Economides. “The minute you experience it it’s impossible to step back and forget it,” says the functional geneticist who runs the skeletal disease program at Regeneron Pharmaceuticals in Tarrytown, New York. “It’s devastating in the most profound way.” The few thousand or so people with FOP worldwide live with grueling uncertainty: Some of their muscles or other soft tissues periodically, and abruptly, transform into new bone that permanently immobilizes parts of their bodies. Joints such as elbows or ankles may become frozen in place; jaw motion can be impeded and the rib cage fixed, making eating or even breathing difficult. Twenty years after he first stumbled on FOP, Economides and his colleagues report today that the gene mutation shared by 97% of people with the disease can trigger its symptoms in a manner different than had been assumed—through a single molecule not previously eyed as a suspect. And by sheer chance, Regeneron had a treatment for this particular target in its freezers. The company tested that potential therapy, a type of protein known as a monoclonal antibody, on mice with their own form of FOP and lo and behold, they stopped growing unwelcome new bone. © 2015 American Association for the Advancement of Science.

Keyword: Movement Disorders; Trophic Factors
Link ID: 21377 - Posted: 09.03.2015

Sara Reardon Antipsychotic drugs are widely used to blunt aggressive behaviour in people with intellectual disabilities who have no history of mental illness, a UK survey of medical records finds, even though the medicines may not have a calming effect. The finding is worrisome because antipsychotic drugs can cause severe side effects such as obesity or diabetes. Psychiatry researcher Rory Sheehan and colleagues1 at University College London studied data from 33,016 people with intellectual disabilities from general-care practices in the United Kingdom over a period of up to 15 years. The researchers found that 71% of 9,135 people who were treated with antipsychotics had never been diagnosed with a severe mental illness, and that the drugs were more likely to be prescribed to those who displayed problematic behaviours. “We suspected that this would be the case, but we didn’t know the true extent,” Sheehan says. “We should be worried because the rates are high,” says James Harris, a psychiatrist at Johns Hopkins University in Baltimore, Maryland. But he adds that it is hard to determine whether treatment with antipsychotics is appropriate without knowing what other forms of treatment were available to people in the study. It is possible that medication was the only option available or that it was used to dampen a person's behaviour enough that they could participate in therapy or other types of treatment. Evidence suggests that the drugs are not effective at treating aggressive and disruptive behaviour, says psychiatrist Peter Tyrer of Imperial College London. I © 2015 Nature Publishing Group

Keyword: Schizophrenia; Aggression
Link ID: 21376 - Posted: 09.02.2015

Aftab Ali People who were born prematurely are less intelligent later on in life and earn less money as a result, according to a new study by the University of Warwick. Researchers at the Coventry-based institution said they found a link which connects pre-term birth with low reading and, in particular, maths skills which affect the amount of wealth accumulated as adults. Funded by the Nuffield Foundation, the researchers examined data from two other large studies, following children born more than a decade apart, with one group from 1958 and the other from 1970. In total, more than 15,000 individuals were surveyed – which recruited all children born in a single week in England, Scotland, and Wales. Data were examined for all individuals who were born at between 28 and 42 weeks gestational age, and who had available wealth information at the age of 42. Those participants who were born pre-term – at less than 37 weeks – were compared with those who were born full-term to find both groups’ mathematical ability in childhood had a direct effect on how much they earned as an adult, regardless of later educational qualifications. In order to measure adult wealth, the researchers looked at factors including: family income and social class, housing and employment status, and their own perceptions of their financial situation. In regards to academic abilities, they examined: validated measures for mathematics, reading, and intelligence, along with ratings from teachers and parents. © independent.co.uk

Keyword: Development of the Brain; Intelligence
Link ID: 21375 - Posted: 09.02.2015

Shankar Vedantam Girls often outperform boys in science and math at an early age but are less likely to choose tough courses in high school. An Israeli experiment demonstrates how biases of teachers affect students. RENEE MONTAGNE, HOST: At early ages, girls often outperform boys in math and science classes. Later, something changes. By the time they get into high school, girls are less likely than boys to take difficult math courses and less likely, again, to go into careers in science, technology, engineering or medicine. To learn more about this, David Greene spoke with NPR social science correspondent Shankar Vedantam. SHANKAR VEDANTAM, BYLINE: Well, the new study suggests, David, that some of these outcomes might be driven by the unconscious biases of elementary school teachers. What's remarkable about the new work is it doesn't just theorize about the gender gap, it actually has very hard evidence. Edith Sand at Tel Aviv University and her colleague, Victor Lavy, analyzed the math test scores of about 3,000 students in Tel Aviv. When the students were in sixth grade, the researchers got two sets of math test scores. One set of scores were given by the classroom teachers, who obviously knew the children whom they were grading. The second set of scores were from external teachers who did not know if the children they were grading were either boys or girls. So the external teachers were blind to the gender of the children. © 2015 NPR

Keyword: Sexual Behavior; Attention
Link ID: 21374 - Posted: 09.02.2015

By Simon Makin Scientists claim to have discovered the first new human prion in almost 50 years. Prions are misfolded proteins that make copies of themselves by inducing others to misfold. By so doing, they multiply and cause disease. The resulting illness in this case is multiple system atrophy (MSA), a neurodegenerative disease similar to Parkinson's. The study, published August 31 in Proceedings of the National Academy of Sciences, adds weight to the idea that many neurodegenerative diseases are caused by prions. In the 1960s researchers led by Carleton Gajdusek at the National Institutes of Health transmitted kuru, a rare neurodegenerative disease found in Papua New Guinea, and Creutzfeldt–Jakob disease (CJD), a rare human dementia, to chimpanzees by injecting samples from victims' brains directly into those of chimps. It wasn't until 1982, however, that Stanley Prusiner coined the term prion (for “proteinaceous infectious particle”) to describe the self-propagating protein responsible. Prusiner and colleagues at the University of California, San Francisco, showed this process caused a whole class of diseases, called spongiform encephalopathies (for the spongelike appearance of affected brains), including the bovine form known as “mad cow” disease. The same protein, PrP, is also responsible for kuru, which was spread by cannibalism; variant-CJD, which over 200 people developed after eating beef infected with the bovine variety; and others. The idea that a protein could transmit disease was radical at the time but the work eventually earned Prusiner the 1997 Nobel Prize in Physiology or Medicine. He has long argued prions may underlie other neurodegenerative diseases but the idea has been slow to gain acceptance. © 2015 Scientific American

Keyword: Prions; Parkinsons
Link ID: 21373 - Posted: 09.02.2015