By Jan Hoffman As adults age, vision deteriorates. One common type of decline is in contrast sensitivity, the ability to distinguish gradations of light to dark, making it possible to discern where one object ends and another begins. When an older adult descends a flight of stairs, for example, she may not tell the edge of one step from the next, so she stumbles. At night, an older driver may squint to see the edge of white road stripes on blacktop. Caught in the glare of headlights, he swerves. But new research suggests that contrast sensitivity can be improved with brain-training exercises. In a study published last month in Psychological Science, researchers at the University of California, Riverside, and Brown University showed that after just five sessions of behavioral exercises, the vision of 16 people in their 60s and 70s significantly improved. After the training, the adults could make out edges far better. And when given a standard eye chart, a task that differed from the one they were trained on, they could correctly identify more letters. “There’s an idea out there that everything falls apart as we get older, but even older brains are growing new cells,” said Allison B. Sekuler, a professor of psychology, neuroscience and behavior at McMaster University in Ontario, who was not involved in the new study. “You can teach an older brain new tricks.” The training improved contrast sensitivity in 16 young adults in the study as well, although the older subjects showed greater gains. That is partly because the younger ones, college students, already had reasonably healthy vision and there was not as much room for improvement. Before the training, the vision of each adult, young and older, was assessed. The exercises were fine-tuned at the beginning for each individual so researchers could measure improvements, said Dr.G. John Andersen, the project’s senior adviser and a psychology professor at the University of California, Riverside. © 2015 The New York Times Company

Keyword: Vision; Development of the Brain
Link ID: 20763 - Posted: 04.07.2015

By KEN BELSON One of the limitations of studying chronic traumatic encephalopathy, or C.T.E., the degenerative brain disease linked to repeated head trauma, has been that researchers have been able to detect it only in tissue obtained posthumously. A study published Monday by Proceedings of the National Academy of Sciences, though, suggests that researchers trying to develop a test that will detect the disease in living patients have taken a small step forward. The study, conducted at U.C.L.A., included 14 retired N.F.L. players who suffered from mood swings, depression and cognitive problems associated with C.T.E. The players were given PET, or positron emission tomography, scans that revealed tau protein deposits in their brains, a signature of C.T.E. Although the results were not conclusive, the distribution of tau in their brains was consistent with those found in the autopsies of players who had C.T.E. The 14 players were compared with 24 patients with Alzheimer’s disease and 28 patients in a control group with no significant cognitive problems. The scans showed that the tau deposits in the 14 players were “distinctly different” from those in the patients with Alzheimer’s disease. “There seems to be an emerging new pattern we haven’t seen in any known forms of dementia, and it is definitely not normal,” said Dr. Julian Bailes, a coauthor of the study and the chairman of neurosurgery at NorthShore Neurological Institute in Evanston, Ill. © 2015 The New York Times Company

Keyword: Brain Injury/Concussion; Brain imaging
Link ID: 20762 - Posted: 04.07.2015

by Hal Hodson For a few days last summer, a handful of students walked through a park behind the University of Hannover in Germany. Each walked solo, but followed the same route as the others: made the same turns, walked the same distance. This was odd, because none of them knew where they were going. Instead, their steps were steered from a phone 10 paces behind them, which sent signals via bluetooth to electrodes attached to their legsMovie Camera. These stimulated the students' muscles, guiding their steps without any conscious effort. Max Pfeiffer of the University of Hannover was the driver. His project directs electrical currentMovie Camera into the students' sartorius, the longest muscle in the human body, which runs from the inside of the knee to the top of the outer thigh. When it contracts, it pulls the leg out and away from the body. To steer his test subjects left, Pfeiffer would zap their left sartorius, opening their gait and guiding them in that direction. Pfeiffer hopes his system will free people's minds up for other things as they navigate the world, allowing them to focus on their conversation or enjoy their surroundings. Tourists could keep their eyes on the sights while being imperceptibly guided around the city. Acceptance may be the biggest problem, although it is possible that the rise of wearable computing might help. Pfeiffer says the electrode's current causes a tingling sensation that diminishes the more someone uses the system. Volunteers said they were comfortable with the system taking control of their leg muscles, but only if they felt they could take control back. © Copyright Reed Business Information Ltd

Keyword: Robotics
Link ID: 20761 - Posted: 04.06.2015

Drawing on the widest survey of sexual behaviour since the Kinsey Report, David Spiegelhalter, in his book Sex By Numbers, answers key questions about our private lives. Here he reveals how Kinsey’s contested claim that 10% of us are gay is actually close to the mark For a single statistic to be the primary propaganda weapon for a radical political movement is unusual. Back in 1977, the US National Gay Task Force (NGTF) was invited into the White House to meet President Jimmy Carter’s representatives – a first for gay and lesbian groups. The NGTF’s most prominent campaigning slogan was “we are everywhere”, backed up by the memorable statistical claim that one in 10 of the US population was gay – this figure was deeply and passionately contested. So where did Bruce Voeller, a scientist who was a founder and first director of the NGTF, get this nice round 10% from? To find out, we have to delve back into Alfred Kinsey’s surveys in 1940s America, which were groundbreaking at the time but are now seen as archaic in their methods: he sought out respondents in prisons and the gay underworld, made friends with them and, over a cigarette, noted down their behaviours using an obscure code. Kinsey did not believe that sexual identity was fixed and simply categorised, and perhaps his most lasting contribution was his scale, still used today, in which individuals are rated from exclusively heterosexual to exclusively homosexual on a scale of 0 to 6. Kinsey’s headline finding was that “at least 37% of the male population has some homosexual experience between the beginning of adolescence and old age”, meaning physical contact to the point of orgasm. © 2015 Guardian News and Media Limited

Keyword: Sexual Behavior
Link ID: 20760 - Posted: 04.06.2015

by Alison George Misguided notions about our sexual appetites are missing the bigger picture and making people unhappy, says Emily Nagoski Why is there no such thing as a sex drive? A drive is a motivational system to deal with life-or-death issues, like hunger or being too cold. You're not going to die if you don't have sex. But biologists might say that if you don't reproduce, that is a form of death Yes. That's the argument that was used when desire was being added to the way sexual dysfunctions were diagnosed in the 1970s, to justify the framing of sexual desire as a drive. But when it comes to sex, there just isn't any physical evidence of a drive mechanism. So what's going on? If sex is a drive then desire should be spontaneous, like a hunger. When you see a sexy person or have a stray sexy thought, it activates an internal craving or urge for sex. That's called "spontaneous desire". It feels like it comes out of the blue. But there is another way of experiencing desire which is also healthy and normal, called "responsive desire", where your interest only emerges in response to arousal. So, your partner comes over and starts kissing your neck and you're like, "oh, right, sex, that's a good idea". Do you think an absence of spontaneous desire is normal? Yes. If our metaphor for desire is hunger, if you are never hungry for food there will be dire consequences and that's clearly a disorder, right? That's a medical problem that needs to be fixed. But not experiencing spontaneous hunger for sex doesn't have dire consequences; it is not a medical disorder. I think the reason we expect everyone to have spontaneous desire is because that's how most men experience it. © Copyright Reed Business Information Ltd

Keyword: Sexual Behavior
Link ID: 20759 - Posted: 04.06.2015

by Bethany Brookshire A new round of dietary do’s and don’ts accompanied last month’s scientific report on the latest food research, summarizing everything from aspartame to saturated fats. The report puts eggs back on the menu. High dietary cholesterol is no longer linked to blood cholesterol in most healthy people. But what grabbed the headlines? Coffee, of course. Many of us are happy to raise a mug to our legal stimulant of choice, especially with the report’s suggestion that three to five cups of joe get a pass. But where do these numbers come from? What science do nutrition experts take into account to determine whether coffee is harmful or safe? And — perhaps the most important question — what does “three to five cups” really mean? The good news for coffee comes from the 2015 Dietary Guidelines Advisory Committee, a group of experts in nutrition and health appointed by the Department of Health and Human Services and the U.S. Department of Agriculture to review the science behind what Americans should eat. The report, released February 19, is not the be-all-end-all of what should be on our plates and in our cups. Instead, it’s a scientific report intended to help the HHS and USDA make policy decisions for the next edition of the Dietary Guidelines for Americans, due out later this year. This is the first time the U.S. Dietary Guidelines have addressed coffee at all. But now, there is enough science on coffee to make a closer look worthwhile, says Tom Brenna, a food scientist at Cornell University and a member of the Committee. “There was so much evidence out there,” he says. “Instead of just five or six papers on the subject, there’s a huge number.” © Society for Science & the Public 2000 - 2015

Keyword: Drug Abuse
Link ID: 20758 - Posted: 04.06.2015

by Andy Coghlan Who needs sight to get around when you've got a digital compass in your head? A neuroprosthesis that feeds geomagnetic signals into the brains of blind rats has enabled them to navigate around a maze. The results demonstrate that the rats could rapidly learn to deploy a completely unnatural "sense". It raises the possibility that humans could do the same, potentially opening up new ways to treat blindness, or even to provide healthy people with extra senses. "I'm dreaming that humans can expand their senses through artificial sensors for geomagnetism, ultraviolet, radio waves, ultrasonic waves and so on," says Yuji Ikegaya of the University of Tokyo in Japan, head of the team that installed and tested the 2.5-gram implant. "Ultrasonic and radio-wave sensors may enable the next generation of human-to-human communicationMovie Camera," he says. The neuroprosthesis consists of a geomagnetic compass – a version of the microchip found in smartphones – and two electrodes that fit into the animals' visual cortices, the areas of the brain that process visual information. Whenever the rat positioned its head within 20 degrees either side of north, the electrodes sent pulses of electricity into its right visual cortex. When the rat aligned its head in a southerly direction, the left visual cortex was stimulated. The stimulation allowed blind rats to build up a mental map of their surroundings without any visual cues. During training, blind rats equipped with digital compasses improved at finding food rewards in a five-pronged maze, despite being released from one of three different arms of the maze at random each time. © Copyright Reed Business Information Ltd

Keyword: Vision; Robotics
Link ID: 20757 - Posted: 04.04.2015

Cory Turner To survive, we humans need to be able to do a handful of things: breathe, of course. And drink and eat. Those are obvious. We're going to focus now on a less obvious — but no less vital — human function: learning. Because new research out today in the journal Science sheds light on the very building blocks of learning. Imagine an 11-month-old sitting in a high chair opposite a small stage where you might expect, say, a puppet show. Except this is a lab at Johns Hopkins University. Instead of a puppeteer, a researcher is rolling a red and blue striped ball down a ramp, toward a little wall at the bottom. Even babies seem to know the ball can't go through that wall, though not necessarily because they learned it. It's what some scientists call core knowledge — something, they say, we're born with. "Some pieces of knowledge are so fundamental in guiding regular, everyday interactions with the environment, navigating through space, reaching out and picking up an object, avoiding an oncoming object — those things are so fundamental to survival that they're really selected for by evolution," says Lisa Feigenson, a professor of psychological and brain sciences at Hopkins and one of the researchers behind this study. Which explains why the baby seems genuinely surprised when the ball rolls down the ramp and does go through the wall — thanks to some sleight of hand by the researchers: © 2015 NPR

Keyword: Development of the Brain
Link ID: 20756 - Posted: 04.04.2015

By Matt McFarland The individuals who have founded some of the most success tech companies are decidedly weird. Examine the founder of a truly innovative company and you’ll find a rebel without the usual regard for social customs. This begs the question, why? Why aren’t more “normal” people with refined social graces building tech companies that change the world? Why are only those on the periphery reaching great heights? If you ask tech investor Peter Thiel, the problem is a social environment that’s both powerful and destructive. Only individuals with traits reminiscent of Asperger’s Syndrome, which frees them from an attachment to social conventions, have the strength to create innovative businesses amid a culture that discourages daring entrepreneurship. “Many of the more successful entrepreneurs seem to be suffering from a mild form of Asperger’s where it’s like you’re missing the imitation, socialization gene,” Thiel said Tuesday at George Mason University. “We need to ask what is it about our society where those of us who do not suffer from Asperger’s are at some massive disadvantage because we will be talked out of our interesting, original, creative ideas before they’re even fully formed. Oh that’s a little bit too weird, that’s a little bit too strange and maybe I’ll just go ahead and open the restaurant that I’ve been talking about that everyone else can understand and agree with, or do something extremely safe and conventional.” An individual with Asperger’s Syndrome — a form of autism — has limited social skills, a willingness to obsess and an interest in systems. Those diagnosed with Asperger’s Syndrome tend to be unemployed or underemployed at rates that far exceed the general population. Fitting into the world is difficult.

Keyword: Autism
Link ID: 20755 - Posted: 04.04.2015

Emily Hodgkin As a nation we think we understand autism. Since the first discovery of the condition just over 70 years ago awareness of autism has continued to grow. Despite this, 87 per cent of people affected by autism think the general public has a bad understanding of the condition. Many of the common myths surrounding autism have been debunked - including the perception that people with autism can’t hold a job. But only 15 per cent of adults in the UK with autism are in full-time employment, while 61 per cent of people with autism currently not in employment say they want to work. Research suggests that employers are missing out on abilities that people on the autism spectrum have in greater abundance – such as heightened abilities in pattern recognition and logical reasoning, as well as a greater attention to detail. Mark Lever, chief executive of the National Autistic Society (NAS) said: "It's remarkable that awareness has increased so much since the NAS was set up over 50 years ago, a time when people with the condition were often written off and hidden from society. But, as our supporters frequently tell us and the poll confirms, there is still a long way to go before autism is fully understood and people with the condition are able to participate fully in their community. All too often we still hear stories of families experiencing judgemental attitudes or individuals facing isolation or unemployment due to misunderstandings or myths around autism.” There are around 700,000 autistic people in the UK – more than 1 in a 100. So as it's more common than perhaps expected, what other myths still exist? © independent.co.uk

Keyword: Autism
Link ID: 20754 - Posted: 04.04.2015

By Shereen Lehman (Reuters Health) - Children exposed to tobacco smoke at home are up to three times more likely to have attention deficit hyperactive disorder (ADHD) as unexposed kids, according to a new study from Spain. The association was stronger for kids with one or more hours of secondhand smoke exposure every day, the authors found. And the results held when researchers accounted for parents' mental health and other factors. "We showed a significant and substantial dose-response association between (secondhand smoke) exposure in the home and a higher frequency of global mental problems," the authors write in Tobacco Control, online March 25. According to the Centers for Disease Control and Prevention, two of every five children in the US are exposed to secondhand smoke regularly. Alicia Padron of the University of Miami Miller School of Medicine in Florida and colleagues in Spain analyzed data from the 2011 to 2012 Spanish National Health Interview Survey, in which parents of 2,357 children ages four to 12 reported the amount of time their children were exposed to secondhand smoke every day. The parents also filled out questionnaires designed to evaluate their children's mental health. According to the results, about eight percent of the kids had a probable mental disorder. About 7% of the kids were exposed to secondhand smoke for less than one hour per day, and 4.5% were exposed for an hour or more each day. © 2015 Scientific American,

Keyword: ADHD; Drug Abuse
Link ID: 20753 - Posted: 04.04.2015

By Amy Ellis Nutt and Brady Dennis For people with amyotrophic lateral sclerosis, which attacks the body’s motor neurons and renders a person unable to move, swallow or breathe, the search for an effective treatment has been a crushing disappointment. The only drug available for the disease, approved two decades ago, typically extends life just a few months. Then in the fall, a small California biotech company named Genervon began extolling the benefits of GM604, its new ALS drug. In an early-stage trial with 12 patients, the results were “statistically significant,” “very robust” and “dramatic,” the company said in news releases. Such enthusiastic pronouncements are unusual for such a small trial. In February, Genervon took an even bolder step: It applied to the Food and Drug Administration for “accelerated approval,” which allows promising treatments for serious or life-threatening diseases to bypass costly, large-scale efficacy trials and go directly to market. ALS patients responded by pleading with the FDA, in emotional videos and e-mails, to grant broad access to the experimental drug. Online forums lit up, and a Change.org petition calling for rapid approval attracted more than a half-million signatures. “Why would anyone oppose it?” asked ALS patient David Huntley in a letter read aloud in the past week at a rally on Capitol Hill. Huntley, a former triathlete, can no longer speak or travel, so his wife, Linda Clark, flew from San Diego to speak for him.

Keyword: ALS-Lou Gehrig's Disease
Link ID: 20752 - Posted: 04.04.2015

Hannah Devlin, science correspondent They may stop short of singing The Bells of Saint Mary’s, as demonstrated by the mouse organ in Monty Python, but scientists have discovered that male mice woo females with ultrasonic songs. The study shows for the first time that mouse song varies depending on the context and that male mice have a specific style of vocalisation reserved for when they smell a female in the vicinity. In turn, females appear to be more interested in this specific style of serenade than other types of squeak that male mice produce. “It was surprising to me how much change occurs to these songs in different social contexts, when the songs are thought to be innate,” said Erich Jarvis, who led the work at Duke University in North Carolina. “It is clear that the mouse’s ability to vocalise is a lot more limited than a songbird’s or human’s, and yet it’s remarkable that we can find these differences in song complexity.” The findings place mice in an elite group of animal vocalisers, that was once thought to be limited to birds, whales, and some primates. Mouse song is too high-pitched for the human ear to detect, but when listened to at a lower frequency, it sounds somewhere between birdsong and the noise of clean glass being scrubbed. The Duke University team recorded the male mice when they were roaming around their cages, when they were exposed to the smell of female urine and when they were placed in the presence of a female mouse. They found that males sing louder and more complex songs when they smell a female but don’t see her. By comparison, the songs were longer and simpler when they were directly addressing their potential mate, according to the findings published in Frontiers of Behavioural Neuroscience. © 2015 Guardian News and Media Limited

Keyword: Hearing; Sexual Behavior
Link ID: 20751 - Posted: 04.02.2015

Davide Castelvecchi Boots rigged with a simple spring-and-ratchet mechanism are the first devices that do not require power aids such as batteries to make walking more energy efficient. People walking in the boots expend 7% less energy than they do walking in normal shoes, the devices’ inventors report on 1 April in Nature1. That may not sound like much, but the mechanics of the human body have been shaped by millions of years of evolution, and some experts had doubted that there was room for further improvement in human locomotion, short of skating along on wheels. “It is the first paper of which I’m aware that demonstrates that a passive system can reduce energy expenditure during walking,” says Michael Goldfarb, a mechanical engineer at Vanderbilt University in Nashville, Tennessee, who develops exoskeletons for aiding people with disabilities. As early as the 1890s, inventors tried to boost the efficiency of walking by using devices such as rubber bands, says study co-author Gregory Sawicki, a biomedical engineer and locomotion physiologist at North Carolina State University in Raleigh. More recently, engineers have built unpowered exoskeletons that enable people to do tasks such as lifting heavier weights — but do not cut down the energy they expend. (Biomechanists still debate whether the running ‘blades’ made famous by South African sprinter Oscar Pistorius are more energetically efficient than human feet.2, 3) For their device, Sawicki and his colleagues built a mechanism that parallels human physiology. When a person swings a leg forward to walk, elastic energy is stored mostly in the Achilles tendon of their standing leg. That energy is released when the standing leg's foot pushes into the ground and the heel lifts off, propelling the body forwards. “There is basically a catapult in our ankle,” Sawicki says. © 2015 Nature Publishing Group

Keyword: Robotics
Link ID: 20750 - Posted: 04.02.2015

By Catherine Saint Louis Joni Mitchell, 71, was taken to a hospital in Los Angeles on Tuesday after she was found unconscious at her Los Angeles home. In recent years, the singer has complained of a number of health problems, including one particularly unusual ailment: Morgellons disease. People who believe they have the condition report lesions that don’t heal, “fibers” extruding from their skin and uncomfortable sensations like pins-and-needles tingling or stinging. Sufferers may also report fatigue and problems with short-term memory and concentration. But Morgellons is not a medically accepted diagnosis. Scientists have struggled for nearly a decade to find a cause and have come up mostly empty-handed. Researchers at the Centers for Disease Control and Prevention studied 115 people who said they had the condition. In a report published in 2012, they said they were unable to identify an infectious source for the patients’ “unexplained dermopathy.” There was no evidence of an environmental link, and the “fibers” from patients resembled those from clothing that had gotten trapped in a scab or crusty skin. The investigators cast doubt on Morgellons as a distinct condition and said that it might be something doctors were already familiar with: delusional infestation, a psychiatric condition characterized by an unshakable but erroneous belief that one’s skin is infested with bugs or parasites. Drug use can contribute to such delusions, and the investigators noted evidence of drug use — prescription or illicit — in half of the people they examined. Of the 36 participants who completed neuropsychological testing, 11 percent had high scores for depression, and 63 percent, unsurprisingly, were preoccupied with health issues. © 2015 The New York Times Company

Keyword: Pain & Touch
Link ID: 20749 - Posted: 04.02.2015

​​The commonly-prescribed drug acetaminophen or paracetamol does nothing to help low back pain, and may affect the liver when used regularly, a large new international study has confirmed. Reporting in today's issue of the British Medical Journal researchers also say the benefits of the drug are unlikely to be worth the risks when it comes to treating osteoarthritis in the hip or knee. "Paracetamol has been widely recommended as being a safe medication, but what we are saying now is that paracetamol doesn't bring any benefit for patients with back pain, and it brings only trivial benefits to those with osteoarthritis," Gustavo Machado of The George Institute for Global Health and the University of Sydney, tells the Australian Broadcasting Corporation. "In addition to that it might bring harm to those patients." Most international clinical guidelines recommend acetaminophen as the "first choice" of treatment for low back pain and osteoarthritis of the hip and knee. However, despite a trial last year questioning the use of acetaminophen to treat low back pain, there has never been a systematic review of the evidence for this. Machado and colleagues analyzed three clinical trials and confirmed that acetaminophen is no better than placebo at treating low back pain. An analysis of 10 other clinical trials by the researchers quantified for the first time the effect acetaminophen has on reducing pain from osteoarthritis in the knee and hip. "We concluded that it is too small to be clinically worthwhile," says Machado. He says the effects of acetaminophen on the human body are not well understood and just because it can stop headaches, it doesn't mean the drug will work in all circumstances. ©2015 CBC/Radio-Canada.

Keyword: Pain & Touch
Link ID: 20748 - Posted: 04.02.2015

Alison Abbott Historian of psychology Douwe Draaisma knows well how to weave science, history and literature into irresistible tales. Forgetting, his latest collection of essays around the theme of memory, is — like his successful Nostalgia Factory (Yale University Press, 2013) — hard to put down. His vivid tour through the history of memory-repression theories brings home how dangerous and wrong, yet persistent, were the ideas of Sigmund Freud and his intellectual heirs. Freud thought that traumatic memories and shameful thoughts could be driven from the consciousness, but not forgotten. They would simmer in the unconscious, influencing behaviour. He maintained that forcing them out with psychoanalysis, and confronting patients with them, would be curative. Draaisma relates the case of an 18-year-old whom Freud dubbed Dora, diagnosed in 1900 with 'hysteria'. Dora's family refused to believe that the husband of her father's mistress had made sexual advances to her. Among other absurdities, Freud told Dora that her nervous cough reflected her repressed desire to fellate the man. Dora broke off the therapy, which Freud saw as proof of his theory. He thought that patients will naturally resist reawakening painful thoughts. What Dora did not buy, plenty of others did. Psychoanalysis boomed, becoming lucrative. Its principles were adopted in the 1990s by an unlikely alliance of lawyers and some feminists, who argued that repressed memories of childhood abuse could be recovered with techniques such as hypnosis, and used as evidence in court. Many judges went along with it; the rush of claims cast a shadow over genuine cases of abuse, Draaisma points out. We now know from studies of post-traumatic stress disorder that traumatic memories are impossible to repress. They flood into the conscious mind in horrifying flashbacks. © 2015 Macmillan Publishers Limited

Keyword: Learning & Memory
Link ID: 20747 - Posted: 04.02.2015

Helen Shen An ambitious plan is afoot to build the world’s largest public catalogue of neuronal structures. The BigNeuron project, announced on 31 March by the Allen Institute for Brain Science in Seattle, Washington, is designed to help researchers to simulate and understand the human brain. The project might also push neuroscientists to wrestle with fundamental — sometimes even emotional — questions about how to classify neurons. It is the era of the mega-scale brain initiative: Europe’s Human Brain Project aims to model the human brain in a supercomputer, and the US BRAIN Initiative hopes to unravel how networks of neurons work together to produce thoughts and actions. Standing in the way of these projects is a surprising limitation. “We still don’t know how many classes of neurons are in the brain,” says neuroscientist Rafael Yuste at Columbia University in New York City. BigNeuron aims to generate detailed descriptions of tens of thousands of individual neurons from various species, including fruit flies, zebrafish, mice and humans, and to suggest the best computer algorithms for extracting the finely branched shapes of these cells from microscopy data — a difficult and error-prone process. Getting the details of the shapes right is crucial to accurately modelling the behaviour of neurons: their geometry helps to determine how they process and transmit information through electrical and chemical signals. © 2015 Nature Publishing Group

Keyword: Brain imaging
Link ID: 20746 - Posted: 04.01.2015

By Virginia Morell Rats and mice in pain make facial expressions similar to those in humans—so similar, in fact, that a few years ago researchers developed rodent “grimace scales,” which help them assess an animal’s level of pain simply by looking at its face. But scientists have questioned whether these expressions convey anything to other rodents, or if they are simply physiological reactions devoid of meaning. Now, researchers report that other rats do pay attention to the emotional expressions of their fellows, leaving an area when they see a rat that’s suffering. “It’s a finding we thought might be true, and are glad that someone figured out how to do an experiment that shows it,” says Jeffrey Mogil, a neuroscientist at McGill University in Montreal, Canada. Mogil’s lab developed pain grimace scales for rats and mice in 2006, and it discovered that mice experience pain when they see a familiar mouse suffering—a psychological phenomenon known as emotional contagion. According to Mogil, a rodent in pain expresses its anguish through narrowed eyes, flattened ears, and a swollen nose and cheeks. Because people can read these visual cues and gauge the intensity of the animal’s pain, Mogil has long thought that other rats could do so as well. In Japan, Satoshi Nakashima, a social cognition psychologist at NTT Communication Science Laboratories in Kanagawa, thought the same thing. And, knowing that other scientists had recently shown that mice can tell the difference between paintings by Picasso and Renoir, he decided to see if rodents could also discriminate between photographs of their fellows’ expressions. He designed the current experiments as part of his doctoral research. © 2015 American Association for the Advancement of Science

Keyword: Pain & Touch; Emotions
Link ID: 20745 - Posted: 04.01.2015

Mo Costandi During the 1960s, neuroscientists Ronald Melzack and Patrick Wall proposed an influential new theory of pain. At the time, researchers were struggling to explain the phenomenon. Some believed that specific nerve fibres carry pain signals up into the brain, while others argued that the pain signals are transmitted by intense firing of non-specific fibres. Neither idea was entirely satisfactory, because they could not explain why spinal surgery often fails to abolish pain, why gentle touch and other innocuous stimuli can sometimes cause excruciating pain, or why intensely painful stimuli are not always experienced as such. Melzack and Wall’s Gate Control Theory stated that inhibitory neurons in the spinal cord control the relay of pain signals into the brain. Despite having some holes in it, the theory provided a revolutionary new framework for understanding the neural basis of pain, and ushered in the modern era of pain research. Now, almost exactly 50 years after the publication of Melzack and Wall’s theory, European researchers provide direct evidence of gatekeeper cells that control the flow of pain and itch signals from the spinal cord to the brain. The experience that we call “pain” is an extremely complex one that often involves emotional aspects. Researchers therefore distinguish it from nociception, the process by which the nervous system detects noxious stimuli. Nociception is mediated by primary sensory neurons, whose cell bodies are clumped together in the dorsal root ganglia that run alongside the spinal cord. Each has a single fibre that splits in two not far from the cell body, sending one branch out to the skin surface and the other into the spinal cord. © 2015 Guardian News and Media Limited

Keyword: Pain & Touch; Emotions
Link ID: 20744 - Posted: 04.01.2015