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By Rhianna Schmunk, CBC News Researchers from the University of British Columbia are retracting their scientific paper linking aluminum in vaccines to autism in mice, because one of the co-authors claims figures published in the study were deliberately altered before publication — an issue he says he realized after allegations of data manipulation surfaced online. The professor also told CBC News there's no way to know "why" or "how" the figures were allegedly contorted, as he claims original data cited in the study is inaccessible, which would be a contravention of the university's policy around scientific research. The paper looked at the effects of aluminum components in vaccines on immune response in a mouse's brain. It was published in the Journal of Inorganic Biochemistry on Sept. 5. Co-authored by Dr. Chris Shaw and Lucija Tomljenovic, it reported aluminum-triggered responses "consistent with those in autism." Shaw said he and Tomljenovic drew their conclusions from data that was "compiled" and "analyzed" for the paper, rather than raw data. However, subsequent scrutiny has raised questions about the validity of the data, with one doctor calling the paper "anti-vaccine pseudoscience." By the middle of September, commenters on PubPeer — a database where users can examine and comment on published scientific papers — pointed out that figures in the study appeared to have been altered, and in one case lifted directly from a 2014 study also authored by Shaw and Tomljenovic. ©2017 CBC/Radio-Canada.

Keyword: Autism
Link ID: 24199 - Posted: 10.16.2017

By John Horgan To help my students appreciate how science reflects cultural prejudices, I often cite examples from psychiatry. The Diagnostic and Statistical Manual of Mental Disorders, or DSM, which the American Psychiatric Association compiles as a guide to diagnosis and treatment of illness, listed homosexuality as a "sociopathic personality disturbance” in the DSM-I, published in 1952, and as a “sexual deviation” in the DSM-II, published in 1968 (see Further Reading). Homosexuality has been treated with lobotomies, chemical castration, electrical shocks and nausea-inducing drugs as well as psychotherapy. I then tell my students about a bizarre gay-conversion experiment carried out in 1970 by a leading brain-implant researcher, Dr. Robert G. Heath of Tulane University in New Orleans. I mentioned Heath in my recent profile of Jose Delgado, a pioneer in the use of brain implants to manipulate patients’ minds and behavior. Heath was arguably even more ambitious than Delgado in his experiments, and he was not a fringe figure. He had degrees in psychiatry and neurology from Columbia and the University of Pennsylvania. n 1949 he founded Tulane’s department of psychiatry and neurology. He oversaw the department until 1980 but continued working into the 1990s. In his 1996 book Exploring the Mind-Brain Relationship, he reviews his career and speculates that someday “biological methods” might make it possible “for man to live in harmony with his fellow man.” © 2017 Scientific American,

Keyword: Sexual Behavior
Link ID: 24198 - Posted: 10.16.2017

Carl Safina Last week footage of five young elephants being captured in Zimbabwe to sell to zoos travelled round the world. Parks officials used helicopters to find the elephant families, shot sedatives into the young ones, then hazed away family members who came to the aid of the drugged young ones as they fell. The film, shared exclusively with the Guardian, showed the young captives being trussed up and dragged on to trucks. In the final moments of footage, two men repeatedly kick a small dazed elephant in the head. Removing young elephants from their parents and sending them into captivity is largely justified on the basis that they do not feel and suffer as we do. For decades we have been admonished against anthropomorphism – imbuing animals with human-type emotions such as sadness or love. But, actually, humans have these emotions because other animals do as well. Brain science, evolutionary biology, and behavioural science now show that elephants, humans, and many other animals share a near-identical nervous system and likely experience near-identical basic emotions. Human and elephant brains are bathed in the same chemicals that create mood and motivation in us. We are all mammals, and under the skin we are kin. Scientists have watched rats’ brains as they dream, and dogs’ brains showing love. In fact, sperm whales’ family structure is nearly identical to that of elephants. Animals living in stable social groups – apes and monkeys, wolves and wild dogs, hyenas and cats, various birds, some dolphins and others, know who they are and whom they are with. © 2017 Guardian News and Media Limited

Keyword: Emotions; Evolution
Link ID: 24197 - Posted: 10.16.2017

by Sari Harrar, AARP Bulletin, At 99 years old Brenda Milner continues to explore the mind and its relationship to people’'s behavior. You'’re a preeminent neuroscientist, and a professor at Canada's prestigious McGill University. At age 99, what motivates you to keep up your research at the Montreal Neurological Institute and Hospital? I am very curious. Human quirks attract my interest. If you’'re a theoretical person, you can sit and dream up beautiful theories, but my approach is, “What would happen if …”or, “Why is this person doing [that] …”and then, “How can I measure it?” I wouldn't still be working if I didn't find it exciting. AARP Membership: Join or Renew for Just $16 a Year Are you curious in real life, too? Yes. I'm a good "noticer—" of behavior as much as the kind of furniture people have! In the 1950s, you made a revolutionary discovery— that memories are formed in a brain area called the hippocampus, which is now getting lots of attention for its role in memory loss and dementia. Has brain research gotten easier? Nowadays, everyone has functional magnetic resonance imaging. Anybody with access to a medical school can get a good look at the patients' brain while they're alive and young, but it wasn't like that [then]. Psychologists were studying patients who were much older and beginning to show memory impairment. Then they had to wait for their patients to die.

Keyword: Learning & Memory
Link ID: 24196 - Posted: 10.16.2017

By James Gallagher Health and science reporter, BBC News website A hallucinogen found in magic mushrooms can "reset" the brains of people with untreatable depression, raising hopes of a future treatment, scans suggest. The small study gave 19 patients a single dose of the psychedelic ingredient psilocybin. Half of patients ceased to be depressed and experienced changes in their brain activity that lasted about five weeks. However, the team at Imperial College London says people should not self-medicate. There has been a series of small studies suggesting psilocybin could have a role in depression by acting as a "lubricant for the mind" that allows people to escape a cycle of depressive symptoms. But the precise impact it might be having on brain activity was not known. Image copyright Getty Images The team at Imperial performed fMRI brain scans before treatment with psilocybin and then the day after (when the patients were "sober" again). The study, published in the journal Scientific Reports, showed psilocybin affected two key areas of the brain. The amygdala - which is heavily involved in how we process emotions such as fear and anxiety - became less active. The greater the reduction, the greater the improvement in reported symptoms. The default-mode network - a collaboration of different brain regions - became more stable after taking psilocybin. Dr Robin Carhart-Harris, head of psychedelic research at Imperial, said the depressed brain was being "clammed up" and the psychedelic experience "reset" it. He told the BBC News website: "Patients were very ready to use this analogy. Without any priming they would say, 'I've been reset, reborn, rebooted', and one patient said his brain had been defragged and cleaned up." © 2017 BBC

Keyword: Depression; Drug Abuse
Link ID: 24195 - Posted: 10.16.2017

By Elizabeth Pennisi One man’s trash is another man’s treasure, even at the level of the cell. That’s where—according to new research—a waste product of the retina fuels part of the eye that powers the rods and cones that help us sense light. Without this waste, that part of the eye “steals” glucose from the retina, leading to the death of retinal cells and likely vision loss. The finding could help explain why eyesight degenerates with age—and in diseases such as macular degeneration and diabetes. “It’s almost a revolutionary concept” that there is such a tight coupling between the two parts of the eye, says Stephen Tsang, a retina specialist at Columbia University who was not involved in the work. Rods and cones are very active, and they need a lot of energy to do their jobs. Exactly how they get this energy has long been a mystery. In previous studies, researchers showed that a layer of cells beneath the retina, the retinal pigment epithelium (RPE), ferries glucose from the blood to the retina. But it was unclear why the RPE didn’t keep the glucose for itself. After a decade of study, biochemist James Hurley at the University of Washington in Seattle and his colleagues have now shown that the retina’s rods and cones burn the glucose, convert leftovers into a fuel called lactate, and then feed that back to the RPE. “There is a growing consensus that no cell exists on its own in complex tissues like the retina,” says Martin Friedlander, an ophthalmologist at The Scripps Research Institute in San Diego, California, who was not involved with the new work. © 2017 American Association for the Advancement of Science.

Keyword: Vision
Link ID: 24194 - Posted: 10.14.2017

By Jessica Hamzelou A rare sighting of a chimpanzee giving birth in the wild came to a grisly conclusion. Within seconds of the birth, the baby was snatched away and eaten by a male of the same group. The observation explains why female chimpanzees tend to go into hiding for weeks or months when they have their babies. Little is known about how chimpanzees give birth in the wild because only five births have ever been observed, says Hitonaru Nishie of Kyoto University in Japan. Nishie and his colleagues have been studying chimpanzees in Tanzania’s Mahale mountains for the last few years. One of the reasons so few have been witnessed is that the soon-to-be mothers often leave the group when the baby is due, and don’t return until the infant is weeks or months old. This absence has been described as a chimpanzee’s “maternity leave”. So Nishie and his colleague Michio Nakamura were surprised when, at around 11 am one December day, a female member of the chimpanzee group they were observing began to give birth in front of the 20 other members. As soon as the baby was out – and before the mother had even had a chance to touch it – the baby was snatched away by a male member of the group, who then disappeared into the bush. The researchers found him around 1½ hours later, sitting up a tree and eating the infant from the lower half of its body. He ate the entire body within an hour. © Copyright New Scientist Ltd.

Keyword: Aggression
Link ID: 24193 - Posted: 10.14.2017

Heidi Ledford The US government is considering whether to approve a gene therapy to prevent the degradation of cells in the retina (shown here in an image from a scanning electron microscope). Advisers to the US Food and Drug Administration (FDA) have paved the way for the agency’s first approval of a gene therapy to treat a disease caused by a genetic mutation. On 12 October, a panel of external experts unanimously voted that the benefits of the therapy, which treats a form of hereditary blindness, outweigh its risks. The FDA is not required to follow the guidance of its advisers, but it often does. A final decision on the treatment, called voretigene neparvovec (Luxturna), is expected by 12 January. An approval in the lucrative US drug market would be a validation that gene-therapy researchers have awaited for decades. “It’s the first of its kind,” says geneticist Mark Kay of Stanford University in California, of the treatment. “Things are beginning to look more promising for gene therapy.” Luxturna is made by Spark Therapeutics of Philadelphia, Pennsylvania, and is designed to treat individuals who have two mutated copies of a gene called RPE65. The mutations impair the eye’s ability to respond to light, and ultimately lead to the destruction of photoreceptors in the retina. The treatment consists of a virus loaded with a normal copy of the RPE65 gene. The virus is injected into the eye, where the gene is expressed and supplies a normal copy of the RPE65 protein. © 2017 Macmillan Publishers Limited

Keyword: Vision; Genes & Behavior
Link ID: 24192 - Posted: 10.14.2017

By Virginia Morell Dog owners often wonder what—if anything—is going on when their pooches are sleeping. It turns out they may be learning, according to a new study. Researchers in Hungary trained 15 pet dogs to sit and lie down using English phrases instead of the Hungarian they already knew. Afterward, the scientists attached small electrodes to the dogs’ heads to record their brain activity while they slept. Electroencephalograms (EEGs) showed that during 3-hour naps, the dogs’ brains experienced brief, repeated moments of “slow-wave” brain activity, lasting 0.5 to 5 seconds. These bursts—called sleep spindles because they look like a train of fast, rhythmic waves on EEG recordings—occur during non-REM sleep and are known to support memory, learning, general intelligence, and healthy aging in humans and rats. But this is the first time they’ve been studied in detail in dogs. Like those of humans and rats, the dogs’ sleep spindles occur in short cycles in the 9-hertz to 16-hertz range; in humans and rats, these cycles are associated with memory consolidation. The scientists also discovered that the number of spindle sessions per minute correlated with how well the dogs learned their new, foreign vocabulary, the researchers report this week in Scientific Reports. And—just like in humans—females had more spindle sessions per minute than males and performed better during testing. About 30% of the females learned the new words, compared to about 10% of the males. That suggests, the researchers say, that dogs can serve as models to better understand the function of our own sleep spindles. © 2017 American Association for the Advancement of Science

Keyword: Sleep; Learning & Memory
Link ID: 24191 - Posted: 10.14.2017

by Robby Berman Our problem with opioids has been in the news a lot lately, and for good reason: It’s arguably the worst drug problem the U.S. has ever faced. The leading cause of death for people under 50? Opioids. According to the CDC, between 1999 and 2015, over 183,000 Americans have died of overdoses from prescription opioids alone. The agency estimates that more than 1,000 people receive emergency treatment for prescription overdoses every day. While those numbers are leveling off a bit now — perhaps as doctors become more careful about prescribing them — the number of deaths from non-prescription opioids is rising fast. Overdoses are easy to count, but nearly as disturbing, if less visible, is how many people are dependent on these drugs. The CDC estimates that in 2014 that number was two million Americans. The top three prescription opioids causing overdoses, says the CDC, are methadone, oxycodone (including OxyContin®), and hydrocodone (including Vicodin®). The two leading non-prescription killers on the rise are heroin and fentanyl, the drug that killed musician Prince. Experts believe that prescription opioids serve as gateways for illegal ones, so getting prescription use under control may be the key first step. Meanwhile, watch this. If you’ve ever thought that those who become dependent on opioids are weak or have defective personalities — and that these drugs might be safe for others, even you — this video from Lily Fang about how they work in the human brain reveals why these pain-killers are so incredibly dangerous. The video was created for a HarvardX class. © Copyright 2007-2017 & BIG THINK,

Keyword: Drug Abuse
Link ID: 24190 - Posted: 10.13.2017

Haroon Siddique Magic mushrooms may effectively “reset” the activity of key brain circuits known to play a role in depression, the latest study to highlight the therapeutic benefits of psychadelics suggests. Psychadelics have shown promising results in the treatment of depression and addictions in a number of clinical trials over the last decade. Imperial College London researchers used psilocybin – the psychoactive compound that occurs naturally in magic mushrooms – to treat a small number of patients with depression, monitoring their brain function, before and after. Images of patients’ brains revealed changes in brain activity that were associated with marked and lasting reductions in depressive symptoms and participants in the trial reported benefits lasting up to five weeks after treatment. Dr Robin Carhart-Harris, head of psychedelic research at Imperial, who led the study, said: “We have shown for the first time clear changes in brain activity in depressed people treated with psilocybin after failing to respond to conventional treatments. “Several of our patients described feeling ‘reset’ after the treatment and often used computer analogies. For example, one said he felt like his brain had been ‘defragged’ like a computer hard drive, and another said he felt ‘rebooted’. “Psilocybin may be giving these individuals the temporary ‘kick start’ they need to break out of their depressive states and these imaging results do tentatively support a ‘reset’ analogy. Similar brain effects to these have been seen with electroconvulsive therapy.” © 2017 Guardian News and Media Limited

Keyword: Depression; Drug Abuse
Link ID: 24189 - Posted: 10.13.2017

Jo Marchant Male scientists are more likely to share their published work than are women — but only with other men, a study of hundreds of researchers has found. Humans are generally considered to be a highly cooperative species, says Jorg Massen, a cognitive biologist at the University of Vienna. But most of the evidence for that assumption comes from artificial situations such as computerized cooperation tasks. “I wanted to test human prosociality in an everyday situation,” he says. So he chose one of the most competitive situations he could think of: his own field of research psychology. To investigate cooperation among psychologists, Massen turned his fellow researchers into guinea pigs. He and his colleagues e-mailed nearly 300 researchers and asked them to share either a PDF of one of their latest papers, or some raw data (pretending that they wanted to include it in a meta-analysis). The results were published in Scientific Reports on 10 October1. In general, the scientists contacted were highly cooperative, with almost 80% willing to share a PDF and almost 60% willing to send raw data. “I was surprised,” says Massen. “Humans are prosocial even in this competitive field.” Even more unexpected, however, was a strong gender difference in how the scientists responded to the request for help. Massen and his colleagues had wondered whether men might respond more favourably to women, or vice versa. In fact, men were more likely to share, but only with other men. A male–male request was 15% more likely to be granted than any other gender combination. © 2017 Macmillan Publishers Limited,

Keyword: Sexual Behavior; Aggression
Link ID: 24188 - Posted: 10.13.2017

By Helen Thomson The most detailed study yet of orgasm brain activity has discovered why climaxing makes women feel less pain and shown that ‘switching off’ isn’t necessary. It’s not easy to study the brain during orgasm. “A brain scanner like fMRI is the least sexy place in the world,” says Nan Wise at Rutgers University in Newark, New Jersey. “It’s noisy, claustrophobic and cold.” There is also the problem of keeping your head still – movement of little more than the width of a pound coin can render data useless. Despite these hurdles, Wise and her colleagues recruited 10 heterosexual women to lay in a fMRI scanner and stimulate themselves to orgasm. They then repeated the experiment but had their partners stimulate them. Wise’s custom-fitted head stabiliser allowed the team to follow brain activity in 20 second intervals to see what happens just before, during, and after an orgasm. Pain relief Back in 1985, Wise’s colleagues Beverly Whipple and Barry Komisaruk, both at Rutgers, discovered that, during self-stimulation and orgasm, women are less likely to notice painful squeezing of a finger, and can tolerate more of this pain. They found that women’s ability to withstand pain increased by 75 per cent during stimulation, while the level of squeezing at which women noticed the pain more than doubled. Now Wise’s team has explained why. At the point of orgasm, the dorsal raphe nucleus area of the brain becomes more active. This region plays a role in controlling the release of the brain chemical serotonin, which can act as an analgesic, dampening the sensation of pain. © Copyright New Scientist Ltd.

Keyword: Sexual Behavior; Attention
Link ID: 24187 - Posted: 10.13.2017

Laura Sanders The brain’s mapmakers don’t get a break, even for sleep. Grid cells, specialized nerve cells that help keep people and other animals oriented, stay on the clock 24/7, two preliminary studies on rats suggest. Results from the studies, both posted October 5 at bioRxiv.org, highlight the stability of the brain’s ‘inner GPS’ system. Nestled in a part of the brain called the medial entorhinal cortex, grid cells fire off regularly spaced signals as a rat moves through the world, marking a rat’s various locations. Individual grid cells work together to create a mental map of the environment. But scientists didn’t know what happens to this map when an animal no longer needs it, such as during sleep. Grid cells, it turns out, maintain their mapmaking relationships even in sleeping rats, report two teams of researchers, one from the University of Texas at Austin and one from the Norwegian University of Science and Technology in Trondheim. (The Norway group includes the researchers who won a Nobel Prize in 2014 for discovering grid cells (SN Online: 10/6/14).) By eavesdropping on pairs of grid cells, researchers found that the cells maintain similar relationships to each other during sleep as they do during active exploration. For instance, two grid cells that fired off signals nearly in tandem while the rat was awake kept that same pattern during sleep, a sign that the map is intact. The results provide insights into how grid cells work together to create durable mental maps. © Society for Science & the Public 2000 - 2017.

Keyword: Learning & Memory
Link ID: 24186 - Posted: 10.13.2017

Dean Burnett Another day, another powerful man embroiled in a sinister sexual scandal decades in the making. This time it’s powerful Hollywood figure Harvey Weinstein. The moral, ethical and political aspects of this whole mess have been covered extensively elsewhere, and will no doubt continue to be so over the coming days and weeks. However, recent reports suggest that Weinstein has checked himself into a European rehab clinic for sex addiction. This has been met with some not-inconsiderable cynicism, but, even if it is true, wondering whether Weinstein is a sex addict overlooks a more fundamental question: is anyone a sex addict? Because that diagnosis, as commonplace as it may seem, is far from established psychiatric fact. Many people do believe sex addiction is real and serious problem, while others dismiss it outright. Despite it being a widely-used term, it doesn’t feature in either the DSM-V or ICD-10, the two main sources for officially-recognised psychiatric disorders the world over (although that’s not a guarantee of consensus either). How can something that seems, to many, to be so straightforward be the subject of so wide a debate? We all know what sex is, we all know what addiction is, what’s the issue? First, sex is a fundamental drive inherent in practically every human. A large percentage of our brain’s systems are responsible for or at least involved in it. An underlying need to seek out sex and an ability to engage in it as and when we like is a remarkably human trait (well, maybe bonobos too). This has many significant consequences for how our societies and cultures work, but one relevant problem is, at what point do you want sex too much? Because that’s not an easy thing to pin down. Those who don’t support the idea of sex addiction often argue that it’s another attempt to pin a clinical diagnosis on “normal” human behaviour (like the dispute around grief in the DSM-V). Some even compare it to gay conversion therapy, in how it medicalises and tries to undo what is an expression of human sexuality. © 2017 Guardian News and Media Limited

Keyword: Sexual Behavior; Drug Abuse
Link ID: 24185 - Posted: 10.12.2017

By Sara Van Note On a recent Saturday morning, two-year-old Ryleigh and five-year-old Colton Arnett play with brightly colored play dough in the family room of their Albuquerque home. Colton narrates his creations with a gap-toothed smile. “I’m going to use a mold. I’m going to make a boat.” Ryleigh echoes him enthusiastically, “Mold! Boat!” An estimated 30,000 New Mexicans carry the mutation, and the numbers are increasing. Their mother, Lori Dunworth, remarks that Colton and his sister don’t usually play so well together. “Usually she’s a bit of a bully when it comes to toys.” Both Ryleigh and Colton receive speech therapy because of something that happened to Colton several years ago, when Dunworth and her husband, Toby Arnett, first noticed that Colton, who was two at the time, was making repeating clicking sounds while his face twitched on one side. After one episode lasted over 20 minutes, they called their doctor, who told them to take him to the hospital immediately. Colton had suffered a seizure, and scans would later reveal masses in his brain — lesions, it turned out, caused by abnormal blood vessels. “The original impact was devastating,” Arnett says. Colton was ultimately diagnosed with Cerebral Cavernous Malformations (CCM), a rare disease that can cause seizure, stroke, and death. He also tested positive for a genetic mutation that causes the disease, known as the Common Hispanic Mutation. Colton’s sister and his mom also have the mutation. Dunworth had no idea she was the carrier. “I’ve never had any symptoms, no seizures, no paralysis, no nothing,” she says. Copyright 2017 Undark

Keyword: Epilepsy; Genes & Behavior
Link ID: 24184 - Posted: 10.12.2017

By Emily Underwood If you’ve ever found yourself in an MRI machine, you know keeping still isn’t easy. For newborns, it’s nearly impossible. Now, a portable, ultrasonic brain probe about the size of a domino could do similar work, detecting seizures and other abnormal brain activity in real time, according to a new study. It could also monitor growing babies for brain damage that can lead to diseases like cerebral palsy. “This is a window of time we haven’t had access to, and techniques like this are really going to open that up,” says Moriah Thomason, a neuroscientist at Wayne State University in Detroit, Michigan, who wasn’t involved in the new study. Researchers have long been able to take still pictures of the newborn brain and study brain tissue after death. But brain function during the first few weeks of life, which is “utterly essential to future human health,” has always been something of a black box, Thomason says. Two techniques used in adults—functional magnetic resonance imaging (fMRI), which can measure blood flow; and electroencephalography (EEG), which measures electrical activity in the outer layers of the brain—have their drawbacks. FMRI doesn’t work well with squirmy tots, is expensive, and is too big to haul to a delicate baby’s bedside. EEG—which only requires attaching a few wires to someone’s head—can’t penetrate deeper brain structures or show where a seizure begins, critical information for doctors weighing treatment options, says Olivier Baud, a developmental neuroscientist at the Robert Debré University Hospital in Paris. © 2017 American Association for the Advancement of Science.

Keyword: Brain imaging; Development of the Brain
Link ID: 24183 - Posted: 10.12.2017

By Bret Stetka The concept of mindfulness involves focusing on your present situation and state of mind. This can mean awareness of your surroundings, emotions and breathing—or, more simply, enjoying each bite of a really good sandwich. Research in recent decades has linked mindfulness practices to a staggering collection of possible health benefits. Tuning into the world around you may provide a sense of well-being, an array of studies claim. Multiple reports link mindfulness with improved cognitive functioning. One study even suggests it may preserve the tips of our chromosomes, which whither away as we age. Yet many psychologists, neuroscientists and meditation experts are afraid that hype is outpacing the science. In an article released this week in Perspectives on Psychological Science, 15 prominent psychologists and cognitive scientists caution that despite its popularity and supposed benefits, scientific data on mindfulness is woefully lacking. Many of the studies on mindfulness and meditation, the authors wrote, are poorly designed—compromised by inconsistent definitions of what mindfulness actually is, and often void of a control group to rule out the placebo effect. The new paper cites a 2015 review published in American Psychologist reporting that only around 9 percent of research into mindfulness-based interventions has been tested in clinical trials that included a control group. © 2017 Scientific American

Keyword: Stress; Attention
Link ID: 24182 - Posted: 10.12.2017

Hannah Devlin Forget negotiations over who takes out the bin, new research suggests that the ideal home temperature is the vexed question most likely to split households down gender lines. A study found that one third of couples dispute this issue and that four in 10 women covertly turn up the heating behind their partner’s back. The research, which was sponsored by Corgi Homeplan, a company that installs and maintains boilers and thermostats, probably falls short of the rigours of peer-reviewed science. However, there is strong evidence to back up the idea that women are more sensitive to the cold. A 2015 study by Dutch scientists, for instance, found that women are comfortable at a temperature 2.5C warmer than men, typically between 24-25C. Men and women have roughly the same core body temperature, at over 37C; in fact, some studies have found the female core body temperature is slightly higher. However, our perception of temperature depends more on skin temperature, which, for women, tends to be lower. One study reported that the average temperature of women’s hands exposed to cold was nearly 3C degrees lower than that observed in men. The female hormone oestrogen contributes to this because it slightly thickens the blood, reducing the flow to capillaries that supply the body’s extremities. This means that, in women, blood flow to the tips of fingers and toes tends to shut off more readily when it is cold. Research has shown that women tend to feel colder around ovulation, when estrogen levels are high. © 2017 Guardian News and Media Limited

Keyword: Sexual Behavior; Hormones & Behavior
Link ID: 24181 - Posted: 10.12.2017

By Jessica Hamzelou For the first time, researchers have shown that being born by C-section can contribute to obesity in mice. This probably happens because the procedure disrupts a newborn’s microbiome. Until fairly recently, babies were thought to be born with sterile guts free from bacteria. But we now know that babies are born with a gutful of microbes, and that at least some of these come from a mother’s vaginal canal during birth. Babies born by C-section are thought to miss out on these bacteria, which could explain why their microbiomes look different. The ecosystem of microbes that live inside us has been implicated in a range of health issues, so this may explain why babies born by C-section are more likely to grow up overweight, and to develop allergies and asthma in later life. To test if C-sections really do lead to heavier babies, Maria Dominguez-Bello at New York University and her colleagues performed C-sections on 34 pregnant mice, and compared the resulting pups to 35 that were born vaginally. By the time the mice had grown into adults 15 weeks later, there were stark difference in body weight between the two groups. The mice born by C-section were, on average, 33 per cent heavier than those born vaginally. Females seemed particularly affected, says Dominguez-Bello. While the C-section males were around 20 per cent heavier than their vaginally-born counterparts, the females were 70 per cent heavier, she says. “We were very surprised to see this,” she says. “We have no idea why it’s happening.” © Copyright New Scientist Ltd.

Keyword: Obesity
Link ID: 24180 - Posted: 10.12.2017