Chapter 15. Emotions, Aggression, and Stress
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By Diana Kwon Most of us will laugh at a good joke, but we also laugh when we are not actually amused. Fake chuckles are common in social situations—such as during an important interview or a promising first date. “Laughter is really interesting because we observe it across all human cultures and in other species,” says Carolyn McGettigan, a cognitive neuroscientist at Royal Holloway, University of London. “It's an incredibly important social signal.” In a 2013 study, McGettigan, then a postdoctoral researcher at University College London, and her colleagues scanned the brains of 21 participants while they passively listened to clips of laughter elicited by funny YouTube videos or produced on command (with instructions to sound as natural as possible). Subjects whose medial prefrontal cortex “lit up” more when hearing the posed laughter were better at detecting whether laughs were genuine or not in a subsequent test. (This brain region is involved in understanding the viewpoint of others.) “If you hear a laugh that seems ambiguous in terms of what the person means,” McGettigan explains, “it makes sense that you're going to try to work out why this person sounds like this.” In a follow-up study in 2016, McGettigan and her colleagues recruited a fresh set of participants to rate the laugh tracks on various qualities, such as authenticity and positivity. They compared these findings with the original brain data and found that the activity in the medial prefrontal cortex was negatively correlated with the genuineness of the laughs. Their analyses also revealed that both types of laughter engaged the auditory cortices, although activity in these brain regions increased as the laughs became happier, more energetic and more authentic. © 2017 Scientific American,
Link ID: 23528 - Posted: 04.24.2017
By Emily Langer Jaak Panksepp, a neuroscientist who helped reveal the emotional lives of animals by tickling rats and listening to their ultrasonic laughter in experiments that upended his field and opened new possibilities for the treatment of depression and other forms of mental illness, died April 18 at his home in Bowling Green, Ohio. He was 73. The cause was cancer, said his wife, Anesa Miller. For much of his career, Dr. Panksepp was brushed aside by colleagues who accepted the prevailing notion that emotions were uniquely human experiences. Dr. Panksepp — along with many pet owners — suspected otherwise, and he sought to prove his intuition through the rigors of science. “People don’t have a monopoly on emotion,” he once said. “Rather, despair, joy and love are ancient, elemental responses that have helped all sorts of creatures survive and thrive in the natural world.” He was long associated with Bowling Green State University where, in the late 1990s, he conducted the experiments with lab rats that would vault him to national renown. He recalled walking into the laboratory one day and remarking to an assistant, “Let’s go tickle some rats.” He credited a graduate student with repurposing a bat detector — a tool capable of recording high-pitched sounds — as the instrument they would use to listen into the rats’ laughterlike chirps. “Lo and behold,” he told the Toledo Blade in 1998, “it sounded like a playground!” © 1996-2017 The Washington Post
Link ID: 23521 - Posted: 04.22.2017
By CATHERINE SAINT LOUIS Halfway through February, I could no longer sleep through the night. At 2 a.m., I’d find myself chugging milk from the carton to extinguish a fire at the top of my rib cage. The gnawing feeling high in my stomach alternated with nausea so arresting I kept a bucket next to my laptop and considered taking a pregnancy test, even though I was 99 percent sure I wasn’t expecting. One day on the subway platform, I doubled over and let out a groan so pathetic it prompted a complete stranger to ask, “Are you all right?” Then I knew it was time to seek medical attention. New Yorkers don’t address strangers on the subway, I told myself. It’s like breaking the fourth wall. The next day, my primary care doctor told me I probably had an ulcer, a raw spot or sore in the lining of the stomach or small intestine. Here are some of the things I learned about ulcers during the odyssey that followed. ■ Anyone Can Get an Ulcer. Back in the 1980s, when doctors and most everyone else thought psychological stress or spicy foods led to ulcers, two Australian scientists discovered that the main culprit was actually a bacterium called Helicobacter pylori. That discovery eventually won them a Nobel Prize in 2005, and ushered in an era of using antibiotics to cure ulcers. But that didn’t wipe out ulcers altogether. Far from it. Indeed, my tribe of fellow sufferers are legion. Nearly 16 million adults nationwide reported having an ulcer in 2014,according to the Centers for Disease Control and Prevention’s National Center for Health Statistics. The largest group, roughly 6.2 million, were 45 to 64 years old. Those 18 to 44 accounted for 4.6 million, 65- to 74-year-olds for 2.6 million, and those 75 and older for 2.4 million. I got a blood test to see if I was infected with H. pylori; the test came back negative, so I didn’t need antibiotics. Regular use of nonsteroidal anti-inflammatory drugs, like ibuprofen or aspirin, can also lead to an ulcer, but I wasn’t taking those medicines. My ulcer turned out to be “idiopathic,” which is a fancy way of saying that doctors have no idea why it happened. © 2017 The New York Times Company
Link ID: 23490 - Posted: 04.14.2017
Sallie Baxendale, Temporal lobe epilepsy—a common form of epilepsy characterized by seizures that begin in the memory-regulating temporal lobe—does appear to influence personality, though not in the way many may think and certainly not in the way people have believed throughout history. The idea of the epileptic personality is an ancient one. Thousands of years ago people with epilepsy were thought to be possessed by either divine beings or demons. In fact, the notion that a seizure represents a kind of communion with another spiritual realm still holds sway in some societies today. In more recent history, Westerners largely perceived epilepsy as a punishment for morally lax behavior. In one 1892 paper, the author claimed that debauchery and excessive lust frequently led to epilepsy and that a person could trigger a seizure by listening to love songs and eating chocolate. More recently, scientists began investigating whether epilepsy, in fact, altered personality. In 1975 neurologists Stephen Waxman and Norman Geschwind, both then at Harvard University, published an analysis based on observations of their patients with temporal lobe epilepsy in which they reported that many patients had a tendency toward religiosity, intense emotions, detailed thoughts, and a compulsion to write or draw. This cluster of characteristics became known as the epileptic personality. Over the next decade other researchers added hostility, aggression, lack of humor and obsessiveness to the list of personality traits supposedly associated with the condition. © 2017 Scientific American
By Gareth Cook The carnivore needs no introduction: fearsome, cold and brutal. But G. A. Bradshaw, known for her psychological work with elephants, asks readers to reconsider. In “Carnivore Minds,” she argues that predators are none of these things. She uses the orca for a case study in the evolution of morals; to explore emotional intelligence, her main example is the crocodile. Through “trans-species psychology,” Bradshaw asks us to consider the many ways that the animals we fear are far more similar to us than we might like to think. She answered questions from Mind Matters editor Gareth Cook. What first lead you to explore the minds of carnivores? Carnivores are a natural counterpoint to the herbivorous elephant, the subject of my previous book, Elephants on the Edge. There certainly are differences between white sharks and elephants, but the similarities are much greater. We know this because of what neuroscience has discovered — mammals, birds, fish, and reptiles (and now, it appears, invertebrates like bees and octopi) share common brain structures and processes that govern thinking and feeling. The scientific model used to explore human minds applies to other animals. This trans-species psychology allows us to see, even experience, the worlds of carnivores as they might — from the inside-out. White sharks, coyotes, and wolves not only have comparable mental and emotional capacities as humans, they are equally vulnerable to psychological trauma. This is what I discovered with the diagnosis of post-traumatic stress disorder (PTSD) in wild elephants. When elephants lose their homes and families, are subjected to mass killing, and are captured and incarcerated in zoos, they breakdown mentally and culturally and exhibit symptoms found in human prisoners and victims of genocide. As a result of hunting and persecution, pumas are showing symptoms of complex PTSD. © 2017 Scientific American
Link ID: 23449 - Posted: 04.05.2017
By GRETCHEN REYNOLDS For generations, mothers have encouraged children to take long, slow breaths to fight anxiety. A long tradition of meditation likewise uses controlled breathing to induce tranquillity. Now scientists at Stanford University may have uncovered for the first time why taking deep breaths can be so calming. The research, on a tiny group of neurons deep within the brains of mice, also underscores just how intricate and pervasive the links are within our body between breathing, thinking, behaving and feeling. Breathing is one of the body’s most essential and elastic processes. Our breaths occur constantly and rhythmically, much like our hearts’ steady beating. But while we generally cannot change our hearts’ rhythm by choice, we can alter how we breathe, in some cases consciously, as in holding our breath, or with little volition, such as sighing, gasping or yawning. But how the mind and body regulate breathing and vice versa at the cellular level has remained largely mysterious. More than 25 years ago, researchers at the University of California at Los Angeles first discovered a small bundle of about 3,000 interlinked neurons inside the brainstems of animals, including people, that seem to control most aspects of breathing. They dubbed these neurons the breathing pacemaker. But recently, a group of scientists at Stanford and other universities, including some of the U.C.L.A. researchers, began using sophisticated new genetics techniques to study individual neurons in the pacemaker. By microscopically tracking different proteins produced by the genes in each cell, the scientists could group the neurons into “types.” © 2017 The New York Times Company
Link ID: 23447 - Posted: 04.05.2017
MaryCatherine McDonald, Marisa Brandt, Robyn Bluhm In the wake of World War I, some veterans returned wounded, but not with obvious physical injuries. Instead, their symptoms were similar to those that had previously been associated with hysterical women – most commonly amnesia, or some kind of paralysis or inability to communicate with no clear physical cause. English physician Charles Myers, who wrote the first paper on “shell-shock” in 1915, theorized that these symptoms actually did stem from a physical injury. He posited that repetitive exposure to concussive blasts caused brain trauma that resulted in this strange grouping of symptoms. But once put to the test, his hypothesis didn’t hold up. There were plenty of veterans who had not been exposed to the concussive blasts of trench warfare, for example, who were still experiencing the symptoms of shell-shock. (And certainly not all veterans who had seen this kind of battle returned with symptoms.) We now know that what these combat veterans were facing was likely what today we call post-traumatic stress disorder, or PTSD. We are now better able to recognize it, and treatments have certainly advanced, but we still don’t have a full understanding of just what PTSD is. The medical community and society at large are accustomed to looking for the most simple cause and cure for any given ailment. This results in a system where symptoms are discovered and cataloged and then matched with therapies that will alleviate them. Though this method works in many cases, for the past 100 years, PTSD has been resisting. © 2010–2017, The Conversation US, Inc.
Link ID: 23442 - Posted: 04.04.2017
By Clare Wilson A new kind of brain cell that links breathing rate to alertness has been found in mice. Destroying these neurons made mice very calm and may explain why deep breathing – such as in yoga or meditation – makes us feel relaxed. Kevin Yackle at the University of California, San Francisco, and his team have dubbed these brain cells “pranayama neurons” in reference to a yoga breathing exercise. They identified them using an existing database of gene activity in different mouse brain cells. The pranayama neurons stood out because they are the only type of brain cell in the hindbrain that makes two particular proteins. There are only 350 of these neurons in a mouse’s brain, located at its base in a region responsible for controlling breathing. The researchers found that the cells connect to a nearby brain area known to control alertness. They then genetically engineered three mice so a drug could be used to kill their pranayama neurons, but leave other brain cells untouched. Once these neurons had been destroyed, the animals took more slow breaths. They also spent less time exploring and sniffing, and more time grooming themselves, becoming “super-chilled out”, says Yackle. The normal role of these neurons might be to ensure that when mice are more physically active – such as when exploring a new place – their sniffing and fast breathing trigger a rise in alertness, says Yackle. If the same mechanism is at work in people, slower breathing might make these neurons less active and so lower stress levels. © Copyright Reed Business Information Ltd
Link ID: 23431 - Posted: 03.31.2017
By KATIE THOMAS The Food and Drug Administration approved on Tuesday the first drug to treat a severe form of multiple sclerosis, offering hope to patients who previously had no other options to combat a relentless disease that leads to paralysis and cognitive decline. The federal agency also cleared the drug to treat people with the more common, relapsing form of the disease. “I think that this is a very big deal,” said Dr. Stephen Hauser, the chairman of the neurology department at the University of California, San Francisco, and leader of the steering committee that oversaw the late-stage clinical trials of the drug, ocrelizumab. “The magnitude of the benefits that we’ve seen with ocrelizumab in all forms of M.S. are really quite stunning.” The drug, which will be sold under the brand name Ocrevus by Genentech, showed the most notable results in patients with relapsing multiple sclerosis, appearing to halt progression of the disease with few serious side effects. In patients with the more severe form, primary progressive multiple sclerosis, the drug only modestly slowed patients’ decline, but medical experts described it as an important first step. “This sort of opens the door for us,” said Dr. Fred D. Lublin, who was a crucial investigator for the clinical trial and is director of the Corinne Goldsmith Dickinson Center for Multiple Sclerosis at Mount Sinai Hospital in New York. “Once we open that door, then we do better and better and better. It’s a very encouraging result.” Genentech, which is owned by the Swiss pharmaceutical giant Roche, said Tuesday that it would charge a list price of $65,000 a year, which — though expensive — is 25 percent less than an existing drug, Rebif, that was shown to be clinically inferior to Ocrevus in the two clinical trials that led to Ocrevus’s approval. © 2017 The New York Times Company
Amy Maxmen Before his 33-year-old son became bedridden with chronic fatigue syndrome, biochemist Ronald Davis created technologies to analyse genes and proteins faster, better and more cheaply. Now he aims his inventions at a different target: the elusive inner workings of his son’s malady. In his office at the Stanford Genome Technology Center in Palo Alto, California, Davis holds a nanofabricated cube the size of a gaming die. It contains 2,500 electrodes that measure electrical resistance to evaluate the properties of human cells. When Davis exposed immune cells from six people with chronic fatigue syndrome to a stressor — a splash of common salt — the cube revealed that they couldn’t recover as well as cells from healthy people could. Now his team is fabricating 100 more devices to repeat the experiment, and testing a cheaper alternative — a paper-thin nanoparticle circuit that costs less than a penny to make on an inkjet printer. Davis’s findings, although preliminary, are helping to propel research on chronic fatigue syndrome, also called myalgic encephalomyelitis (ME/CFS), into the scientific mainstream. Physicians used to dismiss the disease as psychosomatic, but studies now suggest that it involves problems in the chemical reactions, or pathways, within cells. “We now have a great deal of evidence to support that this is not only real, but a complex set of disorders,” says Ian Lipkin, an epidemiologist at Columbia University in New York City. “We are gathering clues that will lead to controlled clinical trials.” © 2017 Macmillan Publishers Limited,
Laurel Hamers SAN FRANCISCO — Millennials, rejoice: A winking-face emoji is worth a slew of ironic words. The brain interprets irony or sarcasm conveyed by an emoji in the same way as it does verbal banter, researchers reported March 26 in San Francisco at the Cognitive Neuroscience Society’s annual meeting. Researchers measured brain electrical activity of college students reading sentences ending in various emojis. For example, the sentence “You are such a jerk” was followed by an emoji that matched the words’ meaning (a frowning face), contradicted the words (a smiling face) or implied sarcasm (a winking face). Then the participants assessed the veracity of the sentence—was the person actually a jerk? Some participants read the sentence literally no matter what, said Benjamin Weissman, a linguist at the University of Illinois at Urbana-Champaign. But people who said emojis influenced their interpretation showed different brain activity in response to sentences with a winking emoji than ones with other emojis. A spike in electrical activity occurred 200 milliseconds after reading winky-face sentences, followed by another spike at 600 milliseconds. A similar electrical pattern has been noted in previous studies in which people listened to sentences where intonation conveyed a sarcastic rather than literal interpretation of the words. That peak at 600 milliseconds has been linked to reassessment. It’s as if the brain reads the sentence one way, sees the emoji and then updates its interpretation to fit the new information, Weissman said. |© Society for Science & the Public 2000 - 2017
Link ID: 23417 - Posted: 03.29.2017
Laurel Hamers SAN FRANCISCO — When faced with simple math problems, people who get jittery about the subject may rely more heavily on certain brain circuitry than math-savvy people do. The different mental approach could help explain why people with math anxiety struggle on more complicated problems, researchers reported March 25 at the Cognitive Neuroscience Society’s annual meeting. While in fMRI machines, adults with and without math anxiety evaluated whether simple arithmetic problems, such as 9+2=11, were correct or incorrect. Both groups had similar response times and accuracy on the problems, but brain scans turned up differences. Specifically, in people who weren’t anxious about math, lower activation of the frontoparietal attention network was linked to better performance. That brain network is involved in working memory and problem solving. Math-anxious people showed no correlation between performance and frontoparietal network activity. People who used the circuit less were probably getting ahead by automating simple arithmetic, said Hyesang Chang, a cognitive neuroscientist at the University of Chicago. Because math-anxious people showed more variable brain activity overall, Chang speculated that they might instead be using a variety of computationally demanding strategies. This scattershot approach works fine for simple math, she said, but might get maxed out when the math is more challenging. Citations H. Chang et al. Simple arithmetic: Not so simple for highly math anxious individuals. Cognitive Neuroscience Society Annual Meeting, San Francisco, March 25, 2017. |© Society for Science & the Public 2000 - 2017.
If your parrot is feeling glum, it might be tweetable. Wild keas spontaneously burst into playful behaviour when exposed to the parrot equivalent of canned laughter – the first birds known to respond to laughter-like sounds. The parrots soared after one another in aerobatic loops, exchanged foot-kicking high fives in mid-air and tossed objects to each other, in what seems to be emotionally contagious behaviour. And when the recording stops, so does the party, and the birds go back to whatever they had been doing. We already knew that these half-metre-tall parrots engage in playful behaviour, especially when young. What’s new is that a special warbling call they make has been shown to trigger behaviour that seems to be an equivalent of spontaneous, contagious laughter in humans. Moreover, it’s not just the young ones that respond, adults of both sexes join in the fun too. Raoul Schwing of the University of Veterinary Medicine in Vienna, Austria, and his team played 5-minute recordings to gatherings of between two and a dozen wild keas on a mountainside of New Zealand’s Arthur’s Pass National Park, on the southern island. The group played recordings of the warble sound, or other sounds, including two other frequent kea sounds – a screech and a whistle – plus the alarm call of a local robin species and a bland tone. © Copyright Reed Business Information Lt
/ By Katie Rose Quandt One afternoon in 2013, after swimming and playing outside, 9-year-old Taylor Johnson, from outside Atlanta, began sneezing incessantly. The fit lasted days before stopping abruptly, only to return months later. For a year, her violent sneezing fits came and went, to the bewilderment of a series of doctors. For families, the diagnosis can seem like an answer to their prayers. But there’s a catch: Most doctors won’t treat the diseases — and many don’t believe they even exist. “She was making this noise with her mouth at times 140 to 150 times a minute,” said her mother, Lori Johnson. “She was frantic, she couldn’t eat, she couldn’t sleep.” And “when she wasn’t sneezing, she was very depressed… She lost all interest in anything. Her whole personality just dissolved into nothing.” Then an otolaryngologist (an ear, nose, and throat doctor) realized Taylor wasn’t sneezing at all — the behavior was a repetitive, sneeze-like tic. That prompted a round of visits to neurologists, psychologists, and other specialists, until an allergist finally suggested a set of diagnoses unfamiliar to the Johnsons: PANS and PANDAS. These disorders, a specialist told them, can arise in certain predisposed children when the immune system responds to an infection like strep throat by attacking the brain. The resulting inflammation can lead to violent body tics and OCD-like symptoms. Copyright 2017 Undark
By JULIE REHMEYER and DAVID TULLER What are some of the treatment regimens that sufferers of chronic fatigue syndrome should follow? Many major medical organizations cite two: psychotherapy and a steady increase in exercise. There’s just one problem. The main study that has been cited as proof that patients can recover with those treatments overstated some of its results. In reality, the claim that patients can recover from these treatments is not justified by the data. That’s the finding of a peer-reviewed preliminary re-analysis of previously unpublished data from the clinical trial, the largest ever for chronic fatigue syndrome. Nicknamed the PACE trial, the core findings of the British study appeared in The Lancet in 2011 and Psychological Medicine in 2013. Patients battled for years to obtain the underlying data, and last spring, a legal tribunal in Britain, the General Regulatory Chamber, directed the release of some of the study’s information. The impact of the trial on treatment options for the estimated one million chronic fatigue patients in the United States has been profound. The Mayo Clinic, Kaiser Permanente, WebMD, the American Academy of Family Physicians and others recommend psychotherapy and a steady increase in exercise. But this approach can be harmful. According to a 2015 report from the Institute of Medicine, now the National Academy of Medicine, even minimal activity can cause patients prolonged exhaustion, muscle pain, cognitive problems and more. In severe cases, a short conversation or a trip to the bathroom can deplete patients for hours, days or more. In surveys, patients routinely report deterioration after a program of graded exercise. The psychotherapeutic intervention also encourages patients to increase their activity levels. Many patients (including one of us) have remained ill for years or decades with chronic fatigue syndrome, also known as myalgic encephalomyelitis, or ME/CFS. It can be triggered by a viral infection, resulting in continuing or recurring immunological and neurological dysfunction. The Institute of Medicine dismissed any notion that it is a psychiatric illness. © 2017 The New York Times Company
By Nicole Mortillaro, CBC News Have you ever been witness to an event with a friend only to conclude you both had different accounts about what had occurred? This is known as perception bias. Our views and beliefs can cloud the way we perceive things — and perception bias can take on many forms. New research published in the Journal of Personality and Social Psychology found that people tend to perceive young black men as larger, stronger and more threatening than white men of the same size. This, the authors say, could place them at risk in situations with police. The research was prompted by recent police shootings against black men in the United States — particularly those involving descriptions of men that didn't correspond with reality. Take, for example, the case of Dontre Hamilton. In 2014, the unarmed Hamilton was shot 14 times and killed by police in Milkwaukee. The officer involved testified that he believed he would have been easily overpowered by Hamilton, who he described as having a muscular build. But the autopsy report found that Hamilton was just five foot seven and weighed 169 pounds. Looking at the Hamilton case, as well as many other examples, the researchers sought to determine whether or not there were psychologically driven preconceived notions about black men over white men. ©2017 CBC/Radio-Canada.
By Warren Cornwall The number of years someone spends behind bars can hinge on whether they were clearly aware that they were committing a crime. But how is a judge or jury to know for sure? A new study suggests brain scans can distinguish between hardcore criminal intent and simple reckless behavior, but the approach is far from being ready for the courtroom. The study is unusual because it looks directly at the brains of people while they are engaged in illicit activity, says Liane Young, a Boston College psychologist who was not involved in the work. Earlier research, including work by her, has instead generally looked at the brains of people only observing immoral activity. Researchers led by Read Montague, a neuroscientist at Virginia Tech Carilion Research Insitute in Roanoke and at University College London, used functional magnetic resonance imaging (fMRI), which can measure brain activity based on blood flow. They analyzed the brains of 40 people—a mix of men and women mostly in their 20s and 30s—as they went through scenarios that simulated trying to smuggle something through a security checkpoint. In some cases, the people knew for certain they had contraband in a suitcase. In other cases, they chose from between two and five suitcases, with only one containing contraband (and thus they weren’t sure they were carrying contraband). The risk of getting caught also varied based on how many of the 10 security checkpoints had a guard stationed there. The results showed distinctive patterns of brain activity for when the person knew for certain the suitcase had contraband and when they only knew there was a chance of it, the team reports today in the Proceedings of the National Academy of Sciences. But there was an unexpected twist. Those differing brain patterns only showed up when people were first shown how many security checkpoints were guarded, and then offered the suitcases. In that case, a computer analysis of the fMRI images correctly classified people as knowing or reckless between 71% and 80% of the time. © 2017 American Association for the Advancement of Science
By Diana Kwon Deep in the Amazon rainforests of Bolivia live the Tsimane’, a tribe that has remained relatively untouched by Western civilization. Tsimane’ people possess a unique characteristic: they do not cringe at musical tones that sound discordant to Western ears. The vast majority of Westerners prefer consonant chords to dissonant ones, based on the intervals between the musical notes that compose the chords. One particularly notable example of this is the Devil’s Interval, or flatted fifth, which received its name in the Middle Ages because the sound it produced was deemed so unpleasant that people associated it with sinister forces. The flatted fifth later became a staple of numerous jazz, blues, and rock-and-roll songs. Over the years, scientists have gathered compelling evidence to suggest that an aversion to dissonance is innate. In 1996, in a letter to Nature, Harvard psychologists, Marcel Zentner and Jerome Kagan, reported on a study suggesting that four-month-old infants preferred consonant intervals to dissonant ones. Researchers subsequently replicated these results: one lab discovered the same effect in two-month-olds and another in two-day-old infants of both deaf and hearing parents. Some scientists even found these preferences in certain animals, such as young chimpanzees and baby chickens. “Of course the ambiguity is [that] even young infants have quite a bit of exposure to typical Western music,” says Josh McDermott, a researcher who studies auditory cognition at MIT. “So the counter-argument is that they get early exposure, and that shapes their preference.” © 1986-2017 The Scientist
By Andy Coghlan Tiny particles secreted in response to head injury in the brains of mice could help explain how inflammation spreads and ultimately boosts the risk of developing dementia. Head injuries are increasingly being linked to cognitive problems and degenerative brain disease in later life. Mysterious particles a micrometre in diameter have previously been found in the spinal fluid of people with traumatic brain injury, but their function has remained unknown. Now Alan Faden at the University of Maryland School of Medicine in Baltimore and his colleagues have discovered that activated immune cells called microglia secrete such microparticles in response to brain injury, and they seem to spread inflammation well beyond the injury site itself. They can even cause brain inflammation when injected into uninjured animals. The particles have receptors that latch onto cells, and are packed with chemicals such as interleukins, which trigger inflammation, and fragments of RNA capable of switching whole suites of genes on or off. When Faden injured the brains of sedated mice, the microparticles spread well beyond the site of damage. Further experiments on cultured microglial cells revealed that the microparticles activate resting microglia, making them capable of triggering further inflammation themselves. © Copyright Reed Business Information Ltd.
By Agata Blaszczak-Boxe Recognizing when a friend or colleague feels sad, angry or surprised is key to getting along with others. But a new study suggests that a knack for eavesdropping on feelings may sometimes come with an extra dose of stress. This and other research challenge the prevailing view that emotional intelligence is uniformly beneficial to its bearer. In a study published in the September 2016 issue of Emotion, psychologists Myriam Bechtoldt and Vanessa Schneider of the Frankfurt School of Finance and Management in Germany asked 166 male university students a series of questions to measure their emotional smarts. For example, they showed the students photographs of people's faces and asked them to what extent feelings such as happiness or disgust were being expressed. The students then had to give job talks in front of judges displaying stern facial expressions. The scientists measured concentrations of the stress hormone cortisol in the students' saliva before and after the talk. In students who were rated more emotionally intelligent, the stress measures increased more during the experiment and took longer to go back to baseline. The findings suggest that some people may be too emotionally astute for their own good, says Hillary Anger Elfenbein, a professor of organizational behavior at Washington University in St. Louis, who was not involved in the study. “Sometimes you can be so good at something that it causes trouble,” she notes. Indeed, the study adds to previous research hinting at a dark side of emotional intelligence. A study published in 2002 in Personality and Individual Differences suggested that emotionally perceptive people might be particularly susceptible to feelings of depression and hopelessness. © 2017 Scientific American