By Kerry Grens A variant in the gene for a certain hormone is tied to people eating more carbs. Yet a new study of 451,000 people finds that the allele doesn’t universally mean poorer health. Researchers reported yesterday (April 10) in Cell Reports that those with the sweet-tooth variant actually have lower body fat than others, and no higher risk for type 2 diabetes. They did, however, find a link between the allele and high blood pressure and a thicker waistline. “This goes against the current perception that eating sugar is bad for health. It may reduce body fat because the same allele also results in a lower consumption of protein and fat in the diet,” study coauthor Timothy Frayling, a molecular geneticist at the University of Exeter Medical School in the U.K., says in a press release. “But whilst this version of the gene lowers body fat, it also redistributes fat to the upper body, where it’s more likely to cause harm, including higher blood pressure.” The gene of interest here is FGF21, which encodes fibroblast growth factor 21, a hormone involved in alcohol and sugar consumption and insulin sensitization. The authors note that it’s a target of weight loss interventions. People with a particular allele of FGF21—20 percent of Europeans are homozygous for the variant—tend to consume relatively more sugar and alcohol than those without the allele. To see what consequences this might have on people’s health, Frayling and his colleagues collected data on 451,000 people whose genetic and health information is part of the UK Biobank. © 1986-2018 The Scientist

Keyword: Obesity; Genes & Behavior
Link ID: 24855 - Posted: 04.12.2018

By NICHOLAS BAKALAR Morning people may live longer than night owls, a new study suggests. Researchers studied 433,268 people, aged 38 to 73, who defined themselves as either “definite morning” types, “moderate morning” types, “moderate evening” types or “definite evening” types. They followed their health for an average of six-and-a-half years, tracking cause of death with death certificates. The study is in Chronobiology International. After controlling for age and sex, smoking, body mass index, sleep duration and other variables, they found that compared with “definite morning” types, “definite evening” types had a 10 percent increased risk of dying from any cause. Each increase from “morningness” to “eveningness” was associated with an increased risk for disease. Night owls were nearly twice as likely as early risers to have a psychological disorder and 30 percent more likely to have diabetes. Their risk for respiratory disease was 23 percent higher and for gastrointestinal disease 22 percent higher. The lead author, Kristen L. Knutson, an associate professor of neurology at Northwestern University, said that while being a night owl is partly genetic, people can make adjustments — gradually making bedtime earlier, avoiding using smartphones before bed, and eventually moving themselves out of the “night owl zone.” Although the reasons for their increased mortality remain unclear, she said, “Night owls should know that there may be some health consequences.” © 2018 The New York Times Company

Keyword: Biological Rhythms
Link ID: 24854 - Posted: 04.12.2018

By HEATHER MURPHY A battle over pleasure has broken out. On Twitter and in the pages of scientific journals, psychologists, neurologists and neuroscientists are forging alliances over the question of whether pleasure we get from art is somehow different from the pleasure we get from candy, sex or drugs. The debate was ignited by an opinion piece titled “Pleasure Junkies All Around!” published last year in the journal Proceedings of the Royal Society B. In it, Julia F. Christensen, a neuroscientist at the The Warburg Institute at the University of London who studies people’s responses to dance choreography, argued that many of us have been turned into “mindless pleasure junkies, handing over our free will for the next dopamine shoot” provided by social media, pornography and sugar. She offered up an unconventional solution: art, which she says engages us in ways these other pleasures do not and can “help overwrite the detrimental effects of dysfunctional urges and craving.” The paper struck a nerve with some of her fellow art and pleasure researchers, who published a rebuttal last month in the same journal. The idea that the way that art engages the brain is somehow special has been around for far too long and it is time to kill it off once and for all, they insist. “Christensen has recently argued that the pleasure induced by art is different to the pleasure induced by food, sex, sports, or drugs. Her argument, however, is contradicted by plenty of evidence showing that the pleasure from art is no different in genesis and function to the pleasure induced by food, drugs, and sex,” wrote Marcos Nadal, a psychologist at the University of the Balearic Islands who studies people’s responses to curvilinear lines in architecture and art, and Martin Skov, a neuroscientist at the Danish Research Centre for Magnetic Resonance, who studies decision-making. Their comment spurred others to rally to Dr. Christensen’s defense. The arguments over Dr. Christensen’s paper pointed to disputes within the emerging field of neuroaesthetics, or the study of the neural processes underlying our appreciation and the production of beautiful objects and artworks: © 2018 The New York Times Company

Keyword: Drug Abuse; Attention
Link ID: 24853 - Posted: 04.11.2018

Jason Murugesu We all daydream, whether about marrying Rihanna, discovering a sudden ability to sing opera or never having to answer another email again. Yet it is only in the last few decades that the science behind daydreaming, or mind-wandering as it is termed in most academic literature, has transitioned from the realms of pseudoscience to the cutting edge of cognitive neuroscience. At its most basic, daydreaming is your mind wandering from the here and now. Traditionally, daydreaming was considered to be a single psychological state of mind. This, however, caused conflict in academic literature, and the resulting confusion is the reason why you might read that daydreaming is linked to happiness in one paper, but to depression in the next. Different types of mind-wandering have been conflated. Using neuroimaging techniques, a study conducted last year by the University of York found that different types of daydreams – for example, those which are fantastical, autobiographical, future orientated or past oriented – were built up of different neuronal activation patterns, and by virtue could not be considered a single psychological construct. Nevertheless, if we consider all these types of mind-wandering together, you would be surprised about how much of our waking time we spend daydreaming. In 2008, Professor Matthew Killingsworth, then at Harvard University, used an app that contacted a large group of people at random points of the day to find out how often they were daydreaming. The app would ask its users what they were doing, and whether they were thinking about something else entirely. They found that 46.9 per cent of the time, the user was mind-wandering.

Keyword: Attention
Link ID: 24852 - Posted: 04.11.2018

By Gary Stix Self-help books often extoll the value of resilience. Last year one such primer—Bounce: Overcoming Adversity, Building Resilience and Finding Joy—proclaimed: “By strengthening your inner power, your ability to handle stressful situations and your skill in persevering after setbacks threaten to fell you, you’ll develop real resilience—you’ll develop grit.” This implies weathering adverse life events is a character trait to be cultivated. Exercising, eating right and giving yourself mental pep talks certainly may help. But neuroscientists are learning the story is not quite so simple, and that some people are likely better equipped from birth to deal with adversity. During the last 15 years discoveries about why some brains excel at resisting stress have initiated a search for new drugs to treat depression and post-traumatic stress disorder by enhancing psychological resilience. One of these compounds has now entered early-stage clinical trials. If the drug is safe and works, it will undoubtedly encounter strong demand; depression—the world’s leading cause of mental disability—never enters full remission in more than half the patients treated with psychotherapies and existing antidepressants. But depression does not affect everyone, and the molecular biology of resilience for psychiatric disorders can be clearly seen by inspecting the brains of lab animals. About a third of mice exposed to severe stress (in the form of aggressive attacks by other rodents) seem to breeze through these assaults without developing the social withdrawal, listlessness or other depression and traumalike symptoms displayed by most of their rodent lab-mates. © 2018 Scientific America

Keyword: Depression
Link ID: 24851 - Posted: 04.11.2018

By Ashley Yeager Mothers who take selective serotonin reuptake inhibitors (SSRIs), a class of commonly used antidepressants, while pregnant have babies with distinct structural changes to their brains, researchers report today (April 9) in JAMA Pediatrics. MRI scans of the babies’ brains revealed exposure to the drugs in the womb increased the volumes of the babies’ amygdalae and insular cortices—regions that play a role in processing emotions. “Hopefully these results highlight the fact that something could be going on here,” study coauthor Claudia Lugo-Candelas, a postdoctoral research fellow at Columbia University tells Time. “They point to the fact that there is a signal—we don’t know what it means, or don’t know how long it might last. But we know it’s worth studying.” The number of women using SSRIs while pregnant is increasing, but not much is known about how the medication might affect the brains of developing babies. Studies in animals suggest exposure to SSRIs can change the offspring’s brain circuitry and lead to depressive-like behaviors and anxiety later in life. In the new study, Lugo-Candelas and her colleagues studied the brains of 98 human infants, 16 babies whose mothers were treated for depression with SSRIs during pregnancy, 21 mothers with depression but not treated, and 61 mothers with no history of depression. © 1986-2018 The Scientist

Keyword: Depression; Development of the Brain
Link ID: 24850 - Posted: 04.11.2018

Nicola Davis A man who took part in a chilli pepper eating contest ended up with more than he bargained for when he took on the hottest pepper in the world. After eating a Carolina Reaper pepper, the 34-year-old started dry heaving before developing a pain in his neck that turned into a series of thunderclap headaches: sudden and severe episodes of excruciating pain that peak within a minute. Scoville scale: The hottest chillies in the world– in pictures The Carolina Reaper, which can top 2.2m on the Scoville heat scale, was the world’s hottest pepper at the time of the incident in 2016 – although new breeds called Pepper X and Dragon’s Breath have since reportedly surpassed it. The details, published in the journal BMJ Case Reports, reveal the pain was so terrible the man went to the emergency room at Bassett Medical Center in Cooperstown, a village in New York State. “[A thunderclap headache] lasts for a few minutes and it might be associated with dry-heaving, nausea, vomiting – and then it gets better on its own. But it keeps coming back,” said Dr Kulothungan Gunasekaran of the Henry Ford Health System in Detroit, a co-author of the report, adding that thunderclap headaches can be caused by a number of problems including bleeding inside the brain or blood clots. CT and MRI scans of the man’s brain were taken but showed nothing out of the ordinary. What’s more, the man did not report having any speech or vision problems. © 2018 Guardian News and Media Limited

Keyword: Pain & Touch; Stroke
Link ID: 24849 - Posted: 04.11.2018

By GRETCHEN REYNOLDS If you give a mouse a running wheel, it will run. But it may not burn many additional calories, because it will also start to move differently when it is not on the wheel, according to an interesting new study of the behaviors and metabolisms of exercising mice. The study, published in Diabetes, involved animals, but it could have cautionary implications for people who start exercising in the hopes of losing weight. In recent years, study after study examining exercise and weight loss among people and animals has concluded that, by itself, exercise is not an effective way to drop pounds. In most of these experiments, the participants lost far less weight than would have been expected, mathematically, given how many additional calories they were burning with their workouts. Scientists involved in this research have suspected and sometimes shown that exercisers, whatever their species, tend to become hungrier and consume more calories after physical activity. They also may grow more sedentary outside of exercise sessions. Together or separately, these changes could compensate for the extra energy used during exercise, meaning that, over all, energy expenditure doesn’t change and a person’s or rodent’s weight remains stubbornly the same. Proving that possibility has been daunting, though, in part because it is difficult to quantify every physical movement someone or something makes, and how their movements do or do not change after exercise. Mice, for instance, skitter, dart, freeze, groom, eat, roam, defecate and otherwise flit about in frequent fits and starts. But recently, animal researchers hit upon the idea of using infrared light beams to track how animals move at any given moment in their cages. Sophisticated software then can use that information to map daily patterns of physical activity, showing, second-by-second, when, where and for how long an animal roams, sits, runs or otherwise spends its time. © 2018 The New York Times Company

Keyword: Obesity
Link ID: 24848 - Posted: 04.11.2018

By Alex Therrien Health reporter, BBC News People who suffer brain injuries are at increased risk of dementia later in life, a large study suggests. An analysis of 2.8 million people found those who had one or more traumatic brain injuries were 24% more likely to get dementia than those who had not. The risk was greatest in people who had the injuries in their 20s, who were 63% more likely to get the condition at some point in their life. But independent experts said other lifestyle factors were more important. Dementia, a category of brain diseases that includes Alzheimer's, affects some 47 million people worldwide - a number expected to double in the next 20 years. Previous research has suggested a link between brain injuries - leading causes of which include falls, motor vehicle accidents, and assaults - and subsequent dementia, but evidence has been mixed. This new study, which followed people in Denmark over a 36-year period, found those who had experienced even one mild TBI (concussion) were 17% more likely to get dementia, with the risk increasing with the number of TBIs and the severity of injury. Sustaining the injury at a younger age appeared to further increase the risk of getting the condition, the research found. Those who suffered a TBI in their 30s were 37% more likely to develop dementia later in life, while those who had the injury in their 50s were only 2% more likely to get the condition. © 2018 BBC

Keyword: Brain Injury/Concussion; Alzheimers
Link ID: 24847 - Posted: 04.11.2018

Jon Hamilton An international coalition of brain researchers is suggesting a new way of looking at Alzheimer's. Instead of defining the disease through symptoms like memory problems or fuzzy thinking, the scientists want to focus on biological changes in the brain associated with Alzheimer's. These include the plaques and tangles that build up in the brains of people with the disease. But they say the new approach is intended only for research studies, and isn't yet ready for use by most doctors who treat Alzheimer's patients. If the new approach is widely adopted, it would help researchers study patients whose brain function is still normal, but are likely to develop dementia caused by Alzheimer's. "There is a stage of the disease where there are no symptoms and we need to have some sort of a marker," says Eliezer Masliah, who directs the Division of Neuroscience at the National Institute on Aging. The new approach would be a dramatic departure from the traditional way of looking at Alzheimer's, says Clifford Jack, an Alzheimer's researcher at Mayo Clinic Rochester. In the past, "a person displayed a certain set of signs and symptoms and it was expected that they had Alzheimer's pathology," says Jack, who is the first author of the central paper describing the proposed new "research framework." © 2018 npr

Keyword: Alzheimers
Link ID: 24846 - Posted: 04.10.2018

Ian Sample Science editor Modern humans might never have raised a quizzical eyebrow had Homo sapiens not lost the thick, bony brows of its ancient ancestors in favour of smoother facial features, a new study suggests. Researchers at the University of York believe early humans bore prominent brow ridges as a mark of physical dominance, and as the human face evolved to become smaller and flatter, it became a canvas on which the eyebrows could portray a much richer range of emotions. “We traded dominance or aggression for a wider palette of expression,” said Paul O’Higgins, a professor of anatomy and lead author on the study. “As the face became smaller and the forehead flattened, the muscles in the face could move the eyebrows up and down and we could express all these subtler feelings.” The York team stress their conclusions are speculative, but if they are right, the evolution of smaller, flatter faces may have unleashed the social power of the eyebrow, allowing humans to communicate at a distance in more complex and nuanced ways. “We moved from a position where we wanted to compete, where looking more intimidating was an advantage, to one where it was better to get on with people, to recognise each other from afar with an eyebrow flash, and to sympathise and so on,” said Penny Spikins, a palaeolithic archaeologist at York and co-author on the study, published in Nature Ecology & Evolution. © 2018 Guardian News and Media Limited

Keyword: Emotions; Evolution
Link ID: 24845 - Posted: 04.10.2018

Marisa Taylor, Melissa Bailey By the time Ann Marie Owen, 61, turned to marijuana to treat her pain, she was struggling to walk and talk. She was also hallucinating. For four years, her doctor prescribed a wide range of opioids for transverse myelitis, a debilitating disease that caused pain, muscle weakness and paralysis. The drugs not only failed to ease her symptoms, they hooked her. When her home state of New York legalized marijuana for the treatment of select medical ailments, Owens decided it was time to swap pills for pot. But her doctors refused to help. "Even though medical marijuana is legal, none of my doctors were willing to talk to me about it," she says. "They just kept telling me to take opioids." Cancer Patients Get Little Guidance From Doctors On Using Medical Marijuana Although 29 states have legalized marijuana to treat pain and other ailments, the growing number of Americans like Owen who use marijuana and the doctors who treat them are caught in the middle of a conflict in federal and state laws — a predicament that is only worsened by thin scientific data. Because the federal government considers marijuana a Schedule 1 drug, research on marijuana or its active ingredients is highly restricted and even discouraged in some cases. Underscoring the federal government's position, Health and Human Services Secretary Alex Azar recently pronounced that there was "no such thing as medical marijuana." © 2018 npr

Keyword: Pain & Touch; Drug Abuse
Link ID: 24844 - Posted: 04.10.2018

By Matthew Hutson As artificial intelligence (AI) allows machines to become more like humans, will they experience similar psychological quirks such as hallucinations or depression? And might this be a good thing? Last month, New York University in New York City hosted a symposium called Canonical Computations in Brains and Machines, where neuroscientists and AI experts discussed overlaps in the way humans and machines think. Zachary Mainen, a neuroscientist at the Champalimaud Centre for the Unknown, a neuroscience and cancer research institute in Lisbon, speculated that we might expect an intelligent machine to suffer some of the same mental problems people do. Q: Why do you think AIs might get depressed and hallucinate? A: I’m drawing on the field of computational psychiatry, which assumes we can learn about a patient who’s depressed or hallucinating from studying AI algorithms like reinforcement learning. If you reverse the arrow, why wouldn’t an AI be subject to the sort of things that go wrong with patients? Q: Might the mechanism be the same as it is in humans? A: Depression and hallucinations appear to depend on a chemical in the brain called serotonin. It may be that serotonin is just a biological quirk. But if serotonin is helping solve a more general problem for intelligent systems, then machines might implement a similar function, and if serotonin goes wrong in humans, the equivalent in a machine could also go wrong. © 2018 American Association for the Advancement of Science

Keyword: Robotics; Intelligence
Link ID: 24843 - Posted: 04.10.2018

By BENEDICT CAREY and ROBERT GEBELOFF Victoria Toline would hunch over the kitchen table, steady her hands and draw a bead of liquid from a vial with a small dropper. It was a delicate operation that had become a daily routine — extracting ever tinier doses of the antidepressant she had taken for three years, on and off, and was desperately trying to quit. “Basically that’s all I have been doing — dealing with the dizziness, the confusion, the fatigue, all the symptoms of withdrawal,” said Ms. Toline, 27, of Tacoma, Wash. It took nine months to wean herself from the drug, Zoloft, by taking increasingly smaller doses. “I couldn’t finish my college degree,” she said. “Only now am I feeling well enough to try to re-enter society and go back to work.” Long-term use of antidepressants is surging in the United States, according to a new analysis of federal data by The New York Times. Some 15.5 million Americans have been taking the medications for at least five years. The rate has almost doubled since 2010, and more than tripled since 2000. Nearly 25 million adults, like Ms. Toline, have been on antidepressants for at least two years, a 60 percent increase since 2010. The drugs have helped millions of people ease depression and anxiety, and are widely regarded as milestones in psychiatric treatment. Many, perhaps most, people stop the medications without significant trouble. But the rise in longtime use is also the result of an unanticipated and growing problem: Many who try to quit say they cannot because of withdrawal symptoms they were never warned about. Some scientists long ago anticipated that a few patients might experience withdrawal symptoms if they tried to stop — they called it “discontinuation syndrome.” Yet withdrawal has never been a focus of drug makers or government regulators, who felt antidepressants could not be addictive and did far more good than harm. © 2018 The New York Times Company

Keyword: Depression
Link ID: 24842 - Posted: 04.09.2018

by Kevin Sheth Recently, I cared for an 82-year-old grandfather who was having some trouble opening a jar of jelly. Twenty minutes later, the fork he was using fell out of his hand. Feeling tired, he laid down, and on waking four hours later, he and his wife discovered that his arm was flaccid. That’s when they called 911 and he was taken to a local hospital. The hospital wasn’t a specialized stroke center and transferred him to Yale New Haven Hospital, where I work and where he arrived two hours after his original emergency response call — and almost seven hours from when his symptoms first started. That was too late to prevent permanent disability. As a neurologist, every single day I am left unable to help victims of stroke, despite an effective treatment in hand, simply because they arrived too late. The blood clots in the brain that cause strokes irreversibly change who we are and burden our families. Strokes strike nearly 800,000 Americans each year, killing 140,000 and at a cost to society of $34 billion annually, according to the Centers for Disease Control and Prevention. For over two decades, neurologists and emergency providers have had a drug available that can restore blood flow to the brain, limiting damage, but only 4 percent of stroke patients receive the medication. The drug, known as tissue plasminogen activator (tPA), is a potent blood thinner and was approved as an effective clot-busting treatment by the Food and Drug Administration in 1996. The rub is that patients must receive the medication in the first few hours after experiencing a stroke for it to work. © 1996-2018 The Washington Post

Keyword: Stroke
Link ID: 24841 - Posted: 04.09.2018

By Edith Sheffer PALO ALTO, Calif. — My son’s school, David Starr Jordan Middle School, is being renamed. A seventh grader exposed the honoree, Stanford University’s first president, as a prominent eugenicist of the early 20th century who championed sterilization of the “unfit.” This sort of debate is happening all over the country, as communities fight over whether to tear down Confederate monuments and whether Andrew Jackson deserves to remain on the $20 bill. How do we decide whom to honor and whom to disavow? There are some straightforward cases: Hitler Squares were renamed after World War II; Lenin statues were hauled away after the collapse of the Soviet Union. But other, less famous monsters of the past continue to define our landscape and language. I have spent the past seven years researching the Nazi past of Dr. Hans Asperger. Asperger is credited with shaping our ideas of autism and Asperger syndrome, diagnoses given to people believed to have limited social skills and narrow interests. The official diagnosis of Asperger disorder has recently been dropped from the American Psychiatric Association’s Diagnostic and Statistical Manual of Mental Disorders because clinicians largely agreed it wasn’t a separate condition from autism. But Asperger syndrome is still included in the World Health Organization’s International Classification of Diseases, which is used around the globe. Moreover, the name remains in common usage. It is an archetype in popular culture, a term we apply to loved ones and an identity many people with autism adopt for themselves. Most of us never think about the man behind the name. But we should. © 2018 The New York Times Company

Keyword: Autism
Link ID: 24840 - Posted: 04.09.2018

BCIs have deep roots. In the 18th century Luigi Galvani discovered the role of electricity in nerve activity when he found that applying voltage could cause a dead frog’s legs to twitch. In the 1920s Hans Berger used electroencephalography to record human brain waves. In the 1960s José Delgado theatrically used a brain implant to stop a charging bull in its tracks. One of the field’s father figures is still hard at work in the lab. Eberhard Fetz was a post-doctoral researcher at the University of Washington in Seattle when he decided to test whether a monkey could control the needle of a meter using only its mind. A paper based on that research, published in 1969, showed that it could. Dr Fetz tracked down the movement of the needle to the firing rate of a single neuron in the monkey’s brain. The animal learned to control the activity of that single cell within two minutes, and was also able to switch to control a different neuron. Dr Fetz disclaims any great insights in setting up the experiment. “I was just curious, and did not make the association with potential uses of robotic arms or the like,” he says. But the effect of his paper was profound. It showed both that volitional control of a BCI was possible, and that the brain was capable of learning how to operate one without any help. Some 48 years later, Dr Fetz is still at the University of Washington, still fizzing with energy and still enthralled by the brain’s plasticity. He is particularly interested in the possibility of artificially strengthening connections between cells, and perhaps forging entirely new ones.

Keyword: Robotics
Link ID: 24839 - Posted: 04.09.2018

By Jeff Sebo You might be aware that chimpanzees can recognize themselves in a mirror, communicate through sign language, pursue goals creatively and form long-lasting friendships. You might also think that these are the kinds of things that a person can do. However, you might not think of chimpanzees as persons. The Nonhuman Rights Project does. Since 2013, the group has been working on behalf of two chimpanzees, Kiko and Tommy, currently being held in cages by their “owners” without the company of other chimpanzees. It is asking the courts to rule that Kiko and Tommy have the right to bodily liberty and to order their immediate release into a sanctuary where they can live out the rest of their lives with other chimpanzees. The problem is that under current United States law, one is either a “person” or a “thing.” There is no third option. If you are a person, you have the capacity for rights, including the right to habeas corpus relief, which protects you from unlawful confinement. If you are a thing, you do not have the capacity for rights. And unfortunately, even though they are sensitive, intelligent, social beings, Kiko and Tommy are considered things under the law. In response, the Nonhuman Rights Project is taking a bold position: It is arguing that if every being must be either a person or a thing, then Kiko and Tommy are persons, not things. I agree, and many other philosophers do, too. In February, a group of philosophers, including me, submitted an amicus curiae brief to the New York Court of Appeals in support of legal personhood for Kiko and Tommy. (Members of the group contributed to this article as well.) The court is considering whether to allow the case to proceed. © 2018 The New York Times Company

Keyword: Animal Rights
Link ID: 24838 - Posted: 04.09.2018

By Julie Hecht I’m right handed. Utensils, pens, pencils, and of course my toothbrush are all operated by my right hand. Like roughly 90% of people, my left hand simply isn’t cut out for much on its own. Dogs, outfitted with paws not hands, also appear to prefer one paw over the other. In dogs, paw laterality — or paw preference — is explored not with forks or pencils, but with more dog-appropriate motor tasks. Studies have asked which paw dogs use to reach toward food or which paw they use to remove something from their body, like a blanket. Researchers have even checked which paw dogs first lift to walk down a step and which paw they “give” when asked to “give” paw. To date, it has been assumed that, like us, dogs have a “hand” preference. But Deborah Wells, a longtime laterality researcher, wondered if something was missing. Studies of paw preference typically use only one test to investigate paw preference. As a result, it is unclear whether “dogs harbour consistent paw preferences” or, on the other hand (ha!), whether paw preference instead might be task-specific. Maybe a dog consistently reaches for food with the right paw, but is more likely to lift the left front paw to walk down a step. Wells and colleagues at the Animal Behaviour Center, Queen’s University, Belfast, took the natural next step (ha again!). They tested 32 pet dogs on four different paw preference tests to see whether dog paw preference was consistent across tests. To check preferences over time, a subset was tested 6 months later. This research was recently published in Behavioural Processes. © 2018 Scientific American

Keyword: Laterality
Link ID: 24837 - Posted: 04.09.2018

Aimee Cunningham A deep conviction that one’s skin is contaminated with insects or other objects despite a lack of medical evidence. She was certain her skin was infested: Insects were jumping off; fibers were poking out. Fearful her condition could spread to others, the 50-year-old patient told doctors at the Mayo Clinic in Rochester, Minn., that she was avoiding contact with her children and friends. The patient had delusional infestation, explains Mayo Clinic dermatologist Mark Davis. Sufferers have an unshaking belief that pathogens or inanimate objects pollute their skin despite no medical evidence. Davis and colleagues report online April 4 in JAMA Dermatology that the disorder is not as rare as previously assumed. In the first population-based study of the disorder’s prevalence, the researchers identified 35 cases from 1976 to 2010 reported in Minnesota’s Olmsted County. Based on the findings, the authors estimate 27 out of every 100,000 people in the United States have delusional infestation. Due to the county’s lack of diversity — the population of about 150,000 is predominantly white — the researchers used only the nationwide white population to estimate prevalence, so the result may not be representative of other populations. Delusional infestation has been recognized for decades, albeit under different names. Patients insist they’ve been overtaken with creatures, such as insects, worms or parasites, or inanimate materials like fibers — or both. © Society for Science & the Public 2000 - 2018.

Keyword: Pain & Touch
Link ID: 24836 - Posted: 04.09.2018