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By Michael Price Good luck finding a legislative issue more controversial than gun violence—at least in the United States. Compounding the controversy is a dearth of reliable data, thanks largely to a de facto ban on federally funded firearms research enacted in 1996. Yet a new study funded by Harvard Business School suggests that one policy—a mandatory waiting period between the sale of a gun and its delivery—could save hundreds of U.S. lives each year if implemented nationally. “Absolutely, this study demonstrates a robust association between waiting periods and gun deaths,” says Margaret Formica, a public health researcher at the State University of New York Upstate Medical University in Syracuse who studies firearms deaths but wasn’t involved in the new work. “It’s an innovative way of looking at this issue.” More than 33,000 Americans die each year in gun-related incidents, including accidents, homicides, and suicides, about as many as in vehicle accidents. But regulations that place limits on the sale and ownership of firearms vary widely from state to state, and it’s unclear which measures might actually prevent gun violence. Some research from other countries has suggested that a “cooling off” period between the sale and delivery of a gun can tamp down suicidal impulses and anger-driven violence. So when Harvard University researchers were motivated to contribute to policy-relevant gun research in the wake of the 2012 Sandy Hook Elementary School shooting, such “waiting periods” were an easy jumping-off point. Not only was there past research, but data on waiting-period laws are relatively easy to track down. “Instead of saying, ‘Isn’t it a tragedy, children are dying, oh well, on to the next meeting,’ we decided we wanted to do something,” says Deepak Malhotra, a negotiation and conflict resolution researcher who co-authored the new study with economist Michael Luca. © 2017 American Association for the Advancement of Science

Keyword: Aggression
Link ID: 24205 - Posted: 10.17.2017

Jon Hamilton Brain imaging studies have a diversity problem. That's what researchers concluded after they re-analyzed data from a large study that used MRI to measure brain development in children from 3 to 18. Like most brain imaging studies of children, this one included a disproportionate number of kids who have highly educated parents with relatively high household incomes, the team reported Thursday in the journal Nature Communications. For example, parents of study participants were three times more likely than typical U.S. parents to hold an advanced degree. And participants' family incomes were much more likely to exceed $100,000 a year. So the researchers decided to see whether the results would be different if the sample represented the U.S. population, says Kaja LeWinn, an assistant professor at the University of California, San Francisco School of Medicine. "We were able to weight that data so it looked more like the U.S." in terms of race, income, education and other variables, she says. And when the researchers did that, the picture of "normal" brain development changed dramatically. For instance, when the sample reflected the U.S. population, children's brains reached several development milestones much earlier. © 2017 npr

Keyword: Brain imaging; Development of the Brain
Link ID: 24204 - Posted: 10.17.2017

By DOUGLAS QUENQUA In the days after his son was born, Rob Sandler found the thrill of becoming a new father replaced with dark feelings of dread and hopelessness. Those feelings, coupled with sleep deprivation and stress, culminated in a panic attack during his son’s bris. As a group of old friends was saying goodbye after the ceremony, “I had this feeling that they were leaving and I was stuck in this situation that would never get any better,” said Mr. Sandler, a marketing executive in Dallas. “I just felt trapped.” What followed was months of sadness, anxiety and — perhaps most worrisome of all — a feeling of acute disappointment in his own ability to be a good parent. In recent years, a growing body of research, and the increasing visibility of dads like Mr. Sandler, has given rise to the idea that you don’t have to give birth to develop postpartum depression, the so-called “baby blues.” Studies suggest that the phenomenon may occur in from 7 percent to 10 percent of new fathers, compared to about 12 percent of new mothers, and that depressed dads were more likely to spank their children and less likely to read to them. Now, a University of Southern California study has found a link between depression and sagging testosterone levels in new dads, adding physiological weight to the argument that postpartum depression isn’t just for women anymore. The study also found that while high testosterone levels in new dads helped protect against depression in fathers, it correlated with an increased risk of depression in new moms. “We know men get postpartum depression, and we know testosterone drops in new dads, but we don’t know why,” said Darby Saxbe, a professor of psychology at U.S.C. and an author of the new report. “It’s often been suggested hormones underlie some of the postpartum depression in moms, but there’s been so much less attention paid to fathers. We were trying to put together the pieces to solve this puzzle.” © 2017 The New York Times Company

Keyword: Depression; Sexual Behavior
Link ID: 24203 - Posted: 10.17.2017

Katharina Kropshofer Life is not so different beneath the ocean waves. Bottlenose dolphins use simple tools, orcas call each other by name, and sperm whales talk in local dialects. Many cetaceans live in tight-knit groups and spend a good deal of time at play. That much scientists know. But in a new study, researchers compiled a list of the rich behaviours spotted in 90 different species of dolphins, whales and porpoises, and found that the bigger the species’ brain, the more complex – indeed, the more “human-like” – their lives are likely to be. This suggests that the “cultural brain hypothesis” – the theory that suggests our intelligence developed as a way of coping with large and complex social groups – may apply to whales and dolphins, as well as humans. Writing in the journal, Nature Ecology and Evolution, the researchers claim that complex social and cultural characteristics, such as hunting together, developing regional dialects and learning from observation, are linked to the expansion of the animals’ brains – a process known as encephalisation. The researchers gathered records of dolphins playing with humpback whales, helping fishermen with their catches, and even producing signature whistles for dolphins that are absent – suggesting the animals may even gossip. Another common behaviour was adult animals raising unrelated young. “There is the saying that ‘it takes a village to raise a child’ [and that] seems to be true for both whales and humans,” said Michael Muthukrishna, an economic psychologist and co-author on the study at the London School of Economics. © 2017 Guardian News and Media Limited

Keyword: Evolution
Link ID: 24202 - Posted: 10.17.2017

By HEATHER MURPHY Can a fish be depressed? This question has been floating around my head ever since I spent a night in a hotel across from an excruciatingly sad-looking Siamese fighting fish. His name was Bruce Lee, according to a sign beneath his little bowl. There we were trying to enjoy a complimentary bloody mary on the last day of our honeymoon and there was Bruce Lee, totally still, his lower fin grazing the clear faux rocks on the bottom of his home. When he did finally move, just slightly, I got the sense that he would prefer to be dead. The pleasant woman at the front desk assured me that he was well taken care of. Was I simply anthropomorphizing Bruce Lee, incorrectly assuming his lethargy was a sign of mental distress? When I sought answers from scientists, I assumed that they would find the question preposterous. But they did not. Not at all. It turns out that not only can our gilled friends become depressed, but some scientists consider fish to be a promising animal model for developing anti-depressants. New research, I would learn, has been radically shifting the way that scientists think about fish cognition, building a case that pet and owner are not nearly as different as many assume. “The neurochemistry is so similar that it’s scary,” said Julian Pittman, a professor at the Department of Biological and Environmental Sciences at Troy University in Alabama, where he is working to develop new medications to treat depression, with the help of tiny zebrafish. We tend to think of them as simple organisms, “but there is a lot we don’t give fish credit for.” Dr. Pittman likes working with fish, in part, because they are so obvious about their depression. He can reliably test the effectiveness of antidepressants with something called the “novel tank test.” A zebrafish gets dropped in a new tank. If after five minutes it is hanging out in the lower half, it’s depressed. If it’s swimming up top — its usual inclination when exploring a new environment — then it’s not. In Dr. Pittman’s lab, researchers induce depression in a fish by keeping it drunk on ethanol for two weeks, then cutting off the supply, forcing it into withdrawal. This here is a depressed fish. Both clips, which represent a small segment of the five minute tank test, were extracted at comparable speeds. Troy University © 2017 The New York Times Company

Keyword: Depression; Evolution
Link ID: 24201 - Posted: 10.17.2017

Jules Montague Steve Thomas and I are talking about brain implants. Bonnie Tyler’s Holding Out For a Hero is playing in the background and for a moment I almost forget that a disease has robbed Steve of his speech. The conversation breaks briefly; now I see his wheelchair, his ventilator, his hospital bed. Steve, a software engineer, was diagnosed with ALS (amyotrophic lateral sclerosis, a type of motor neurone disease) aged 50. He knew it was progressive and incurable; that he would soon become unable to move and, in his case, speak. He is using eye-gaze technology to tell me this (and later to turn off the sound of Bonnie Tyler); cameras pick up light reflection from his eye as he scans a screen. Movements of his pupils are translated into movements of a cursor through infrared technology and the cursor chooses letters or symbols. A speech-generating device transforms these written words into spoken ones – and, in turn, sentences and stories form. Eye-gaze devices allow some people with limited speech or hand movements to communicate, use environmental controls, compose music, and paint. That includes patients with ALS – up to 80% have communication difficulties, cerebral palsy, strokes, multiple sclerosis and spinal cord injuries. It’s a far cry from Elle editor-in-chief Jean-Dominique Bauby, locked-in by a stroke in 1995, painstakingly blinking through letters on an alphabet board. His memoir, written at one word every two minutes, later became a film, The Diving Bell and the Butterfly. Although some still use low-tech options (not everyone can meet the physical or cognitive requirements for eye-gaze systems; occasionally, locked-in patients can blink but cannot move their eyes), speech-to-text and text-to-speech functionality on smartphones and tablets has revolutionised communication. © 2017 Guardian News and Media Limited

Keyword: Robotics
Link ID: 24200 - Posted: 10.16.2017

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