Chapter 15. Emotions, Aggression, and Stress
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By Christian Jarrett Most of us like to think that we’re independent-minded — we tell ourselves we like Adele’s latest album because it suits our taste, not because millions of other people bought it, or that we vote Democrat because we’re so enlightened, not because all our friends vote that way. The reality, of course, is that humans are swayed in all sorts of different ways — some of them quite subtle — by other people’s beliefs and expectations. Our preferences don’t form in a vacuum, but rather in something of a social pressure-cooker. This has been demonstrated over and over, perhaps most famously in the classic Asch conformity studies from the ‘50s. In those experiments, many participants went along with a blatantly wrong majority judgment about the lengths of different lines — simply, it seems, to fit in. (Although the finding is frequently exaggerated, the basic point about the power of social influence holds true.) But that doesn’t mean all humans are susceptible to peer pressure in the same way. You only have to look at your own friends and family to know that some people always seem to roll with the crowd, while others are much more independent-minded. What accounts for these differences? A new study in Frontiers in Human Neuroscience led by Dr. Juan Dominguez of Monash University in Melbourne, Australia, offers the first hint that part of the answer may come down to certain neural mechanisms. In short, the study suggests that people have a network in their brains that is attuned to disagreement with other people. When this network is activated, it makes us feel uncomfortable (we experience “cognitive dissonance,” to use the psychological jargon) and it’s avoiding this state that motivates us to switch our views as much as possible. It appears the network is more sensitive in some people than in others, and that this might account for varying degrees of pushover-ness. © 2016, New York Media LLC.
Greg Miller The crime was brutal. On November 4, 1989, after a night of heavy drinking, David Scott Detrich and a male coworker picked up a woman walking along the side of the road in Tucson, Arizona. After scoring some cocaine, the trio went back to her place, where, according to court documents, Detrich slit the woman’s throat and stabbed her 40 times. Later, the two men dumped her body in the desert. A jury convicted Detrich of kidnapping and first-degree murder in 1995, and a judge sentenced him to death. Detrich is still on death row today as the appeals process drags on, but in 2010, his lawyers achieved a victory of sorts. They claimed that Detrich had received “ineffective assistance of counsel” at his trial, because his original legal team had failed to present evidence of neuropsychological abnormalities and brain damage that might have swayed the court to give him a lesser sentence. A federal appeals court agreed. The ruling said, in effect, that Detrich had been denied his Constitutional right to a fair trial because his lawyers hadn’t called an expert witness to talk about his brain. That judicial opinion is just one of nearly 1,600 examined in a recent study documenting the expanding use of brain science in the criminal-justice system. The study, by Nita Farahany at Duke University, found that the number of judicial opinions that mention neuroscientific evidence more than doubled between 2005 and 2012. “There are good reasons to believe that the increase in published opinions involving neurobiology are just the tip of the iceberg,” says Owen Jones, a law professor at Vanderbilt who directs the MacArthur Foundation Research Network on Law and Neuroscience.
Link ID: 21946 - Posted: 03.02.2016
By Nala Rogers Treatments that zap the brain with magnets or electricity are rising in popularity, and some evidence suggests they can help lift depression. But scientists are starting to wonder whether they could be hitting the wrong place in left-handed patients. Now, two small studies suggest this could very well be the case. “This is the kind of question that’s been desperately needed for many years,” says Jim Coan, a clinical psychologist at the University of Virginia in Charlottesville who was not involved in the project. “Most researchers in this area, including myself, have selected samples that are strongly right-handed, just in order to avoid mess in the data.” Past studies have suggested that the spots targeted by both kinds of stimulation—located in the left hemisphere—are likely to process “approach” emotions such as happiness, curiosity, and anger, which drive people to reach out and engage with the world. Some studies have also hinted that the brain’s right hemisphere is more involved in so-called “avoidance” emotions such as sorrow and fear. But the studies that support this separation of emotion into the two halves of the brain have relied almost exclusively on right-handed individuals. To figure out whether something else was happening with lefties, University of Chicago in Illinois neuroscientist Daniel Casasanto designed two studies: one to link personality to patterns of brain activity and another to measure the outcome of common brain stimulation treatments in right-handed and left-handed individuals. The brain stimulation treatments were originally designed to treat depression by boosting feelings of happiness and engagement, which motivate “approach” behaviors such as exploring the world and interacting with friends. © 2016 American Association for the Advancement of Science.
Interview by Tim Adams Professor John Cacioppo has been studying the effects and causes of loneliness for 21 years. He is the director of the University of Chicago’s Center for Cognitive and Social Neuroscience. His book Loneliness: Human Nature and the Need for Social Connection examines the pathology and public health implications of the subject. You have been studying social connection and loneliness for more than two decades. How did you come to it as a subject? It was not biographical, I don’t think. Back in the early 90s I had outlined the new field called social neuroscience, the study of the neural mechanisms within a defined social species. Social species are those that create stable bonds, which have societies and cultures. And neuroscience hadn’t really studied those things. Was it something that neuroscientists, with their emphasis on individual brains and cells, resisted? When I proposed it in 1992, I anticipated some kickback from colleagues, so in the original papers I proposed that “social neuroscience isn’t an oxymoron”, and I explained why. That was all well and good, but I quickly realised that theoretical arguments were not going to be enough on their own. I needed to have a convincing demonstration of social neuroscience. And you chose loneliness for that? Well, I was originally interested in social connections. I argued we are defined by social connections, so what happens in the brain when you absent those? I took one other step. I said that the brain is the organ for creating, monitoring, nurturing and retaining these social connections, so it didn’t matter whether you actually had these connections, what was important was whether you felt that you had them. © 2016 Guardian News and Media Limited
Laura Sanders For some adults, Zika virus is a rashy, flulike nuisance. But in a handful of people, the virus may trigger a severe neurological disease. About one in 4,000 people infected by Zika in French Polynesia in 2013 and 2014 got a rare autoimmune disease called Guillain-Barré syndrome, researchers estimate in a study published online February 29 in the Lancet. Of 42 people diagnosed with Guillain-Barré in that outbreak, all had antibodies that signaled a Zika infection. Most also had recent symptoms of the infection. In a control group of hospital patients who did not have Guillain-Barré, researchers saw signs of Zika less frequently: Just 54 out of 98 patients tested showed signs of the virus. The message from this earlier Zika outbreak is that countries in the throes of Zika today “need to be prepared to have adequate intensive care beds capacity to manage patients with Guillain-Barré syndrome,” writes study coauthor Arnaud Fontanet of the Pasteur Institute in Paris and colleagues, some of whom are from French Polynesia. The study, says public health researcher Ernesto Marques of the University of Pittsburgh, “tells us what I think a lot of people already thought: that Zika can cause Guillain-Barré syndrome.” As with Zika and the birth defect microcephaly (SN: 2/20/16, p. 16), though, more work needs to be done to definitively prove the link. Several countries currently hard-hit by Zika have reported upticks in Guillain-Barré syndrome. Colombia, for instance, usually sees about 220 cases of the syndrome a year. But in just five weeks between mid-December 2015 to late January 2016, doctors diagnosed 86 cases, the World Health Organization reports. Other Zika-affected countries, including Brazil, El Salvador and Venezuela, have also reported unusually high numbers of cases. © Society for Science & the Public 2000 - 2016. All rights reserved.
By Roberto A. Ferdman Poverty has a way of rearing its ugly head, slipping into the cracks in people's lives when they're young and then re-emerging later in life. Sometimes it happens in ways that are easily observable—what poor babies are fed, for instance, has been shown to alter what they crave as adults, creating life-long affinities for foods that might be better left uneaten. But sometimes the influences are hidden, and all the more insidious as a result. A team of researchers, led by Sarah Hill, who teaches psychology at Texas Christian University, believe they have uncovered evidence of one such lingering effect. Specifically, Hill and her colleagues found that people who grow up poor seem to have a significantly harder time regulating their food intake, even when they aren't hungry. "We found that they eat comparably high amounts regardless of their need," said Hill. The researchers, interested in exploring why obesity is more prevalent in poorer populations, devised three separate experiments, which tested how people from different socioeconomic backgrounds behaved in front of food. In the first, they invited 31 female participants into their lab, who were asked how long it had been since they had eaten, and how hungry they were. They were then given snacks (cookies and pretzels), which they were free to eat or leave be, as they pleased. When they were finished, Hill and her team measured the number of calories each consumed. The discrepancy between how the participants ate was alarming.
By Ariana Eunjung Cha The Centers for Disease Control and Prevention just published their first national survey of sleep for all 50 states and the District of Columbia. In many respects, it's consistent with our image of ourselves as bleary-eyed insomniacs downing triple espresso shots and melatonin pills as we stare at our iPhones like zombies. The CDC found that more than a third of American adults are not getting the recommended amount of seven-plus hours of sleep on a regular basis. Here's a look at what sleep looks like across the United States, as broken down by marital status, geography, race/ethnicity and employment. The results aren't always what you might expect. 1. First, here's a breakdown of how much sleep Americans are getting overall. This is based on a random telephone survey of 444,306 respondents. Overall, about 65 percent reported a "healthy sleep duration" (seven or more hours of sleep on a regular basis) and about 35 percent reported they were getting less than that. 2. Being unable to work or being unemployed appears to affect sleep in a negative way. That's consistent with previous research on sleep quality and mental health issues like depression that can be related to unemployment. 3. People with college degrees or higher were more likely to get enough sleep. Maybe it's because they are more likely to know how important good sleep is to your health or maybe because they have jobs or income that allow them to get more sleep?
Alison Abbott. More than 50 years after a controversial psychologist shocked the world with studies that revealed people’s willingness to harm others on order, a team of cognitive scientists has carried out an updated version of the iconic ‘Milgram experiments’. Their findings may offer some explanation for Stanley Milgram's uncomfortable revelations: when following commands, they say, people genuinely feel less responsibility for their actions — whether they are told to do something evil or benign. “If others can replicate this, then it is giving us a big message,” says neuroethicist Walter Sinnot-Armstrong of Duke University in Durham, North Carolina, who was not involved in the work. “It may be the beginning of an insight into why people can harm others if coerced: they don’t see it as their own action.” The study may feed into a long-running legal debate about the balance of personal responsibility between someone acting under instruction and their instructor, says Patrick Haggard, a cognitive neuroscientist at University College London, who led the work, published on 18 February in Current Biology1. Milgram’s original experiments were motivated by the trial of Nazi Adolf Eichmann, who famously argued that he was ‘just following orders’ when he sent Jews to their deaths. The new findings don’t legitimize harmful actions, Haggard emphasizes, but they do suggest that the ‘only obeying orders’ excuse betrays a deeper truth about how a person feels when acting under command. © 2016 Nature Publishing Group
Leo Benedictus It seems so obvious when you hear it, yet it could have shaped society for centuries without our knowing. According to research presented by Dr Daniel Casasanto to the American Association for the Advancement of Science annual conference in Washington DC, people just prefer things that are in front of their favourite hand. It could be products on a shelf, or applicants for a job. “Righties would on average choose the person or product on the right; lefties, on average, the person or product on the left,” Dr Casasanto explained. And, from his research conducted at the University of Chicago, it is easy to see how this could have serious political implications. “We found in a large simulated election, that compared to lefties, righties will choose the candidate they see on the right of the ballot paper about 15% more,” Dr Casasanto said. His theory, in simple terms, is that because people go through life with a “fluent side” and a “clumsy side”, they develop a kind of unconscious favouritism, even for things that don’t require them to use their hands. “It seems blindingly obvious that you will have a preference for that bit of space where you operate more frequently,” says Professor Philip Corr, a psychologist at City University, London. “You’ll feel more comfortable operating in that part of the world. Intuitively it makes sense to me.” Many papers have been published on the subject, but we still don’t really know why people don’t all use the same hand - or an even balance of the two, as do most primates.
By Gretchen Reynolds The benefits of mindfulness meditation, increasingly popular in recent years, are supposed to be many: reduced stress and risk for various diseases, improved well-being, a rewired brain. But the experimental bases to support these claims have been few. Supporters of the practice have relied on very small samples of unrepresentative subjects, like isolated Buddhist monks who spend hours meditating every day, or on studies that generally were not randomized and did not include placebo control groups. This month, however, a study published in Biological Psychiatry brings scientific thoroughness to mindfulness meditation and for the first time shows that, unlike a placebo, it can change the brains of ordinary people and potentially improve their health. To meditate mindfully demands ‘‘an open and receptive, nonjudgmental awareness of your present-moment experience,’’ says J. David Creswell, who led the study and is an associate professor of psychology and the director of the Health and Human Performance Laboratory at Carnegie Mellon University. One difficulty of investigating meditation has been the placebo problem. In rigorous studies, some participants receive treatment while others get a placebo: They believe they are getting the same treatment when they are not. But people can usually tell if they are meditating. Dr. Creswell, working with scientists from a number of other universities, managed to fake mindfulness. First they recruited 35 unemployed men and women who were seeking work and experiencing considerable stress. Blood was drawn and brain scans were given. Half the subjects were then taught formal mindfulness meditation at a residential retreat center; the rest completed a kind of sham mindfulness meditation that was focused on relaxation and distracting oneself from worries and stress. © 2016 The New York Times Company
Link ID: 21907 - Posted: 02.18.2016
Sidharth Gupta always dazzled people with his intelligence. “Everybody used to praise my brother’s brain,” says Isha Gupta , two years his junior. “Everybody. Like, ‘Oh Sidharth, he’s very smart. He’s got a very sharp brain.’ That’s something that I’ve heard all my life. And his brain is what gave up on him.” Two years ago, “Sid” was the picture of exuberance and ambition. Having established his own marketing and event planning business in his native India, he moved to Toronto in 2011 to work as an account executive at Canada’s largest advertising agency, MacLaren McCann. According to Isha, Sid had big dreams. The event management company in India was just the beginning; he was planning to grow it into a worldwide marketing business. Thirty years old at the time, Sid was smart, savvy, on the ball — and always up for fun. He had “insane energy,” says colleague Zain Ali . “He could work all day and then party late and then get back to work the next day.” “Sid was very happy-go-lucky,” says another work friend, Rishi Gupta (no relation). “He had that same smile on his face all the time. He wanted to be part of the party, to have a good time.” That was Sid’s frame of mind on Feb. 20, 2014, as he geared up for a marketing launch at the Canadian International Auto Show in Toronto. After he and Zain put in 12 hours setting up an interactive display for the new Camaro Z28, Sid joined a few friends to celebrate Rishi’s birthday. ©2016 CBC/Radio-Canada.
Colombia says three people have died after contracting the Zika virus and developing a rare nerve disorder. Health Minister Alejandro Gaviria said there was a "causal connection" between Zika, the Guillain-Barre disorder and the three deaths. Earlier, Brazilian scientists said they had detected for the first time active samples of Zika in urine and saliva. However, it is not clear whether the virus can be transmitted through bodily fluids. Zika, a mosquito-borne disease, has been linked to cases of babies born in Brazil with microcephaly - underdeveloped brains. "We have confirmed and attributed three deaths to Zika," said the head of Colombia's National Health Institute, Martha Lucia Ospina. "In this case, the three deaths were preceded by Guillain-Barre syndrome." Guillain-Barre is a rare disorder in which the body's immune system attacks part of the nervous system. It isn't normally fatal. Ms Ospina said another six deaths were being investigated for possible links to Zika. "Other cases (of deaths linked to Zika) are going to emerge," she said. "The world is realising that Zika can be deadly. The mortality rate is not very high, but it can be deadly." Mr Gaviria said one of the fatalities took place in San Andres and the other two in Turbo, in Antioquia department. UK virologist Prof Jonathan Ball, of the University of Nottingham, told the BBC: "We have been saying Zika has been associated with Guillain-Barre. One of the complications of that could be respiratory failure. But it is still probably a very rare event." Although Zika usually causes mild, flu-like symptoms, it has been linked to thousands of suspected birth defects. However, it has not yet been proved that Zika causes either microcephaly or Guillain-Barre. © 2016 BBC
Could a painkiller turn people away from suicide? A preliminary trial of an opioid called buprenorphine shows that the drug can reduce suicidal thoughts after just one week. If validated in larger studies, it could become the first fast-acting anti-suicide drug. Such a drug is sorely needed. The US Centers for Disease Control and Prevention (CDC) estimates that more than 9 million adults in the country reported having suicidal thoughts in 2013. Over a million went on to attempt suicide. “Around 400,000 suicidal people are coming to emergency rooms every year,” says Elizabeth Ballard at the National Institute of Mental Health. “Pharmacologically, nothing has been approved for acute treatment of suicidal ideation so anything that can help them is greatly needed.” When people seek help, they may be offered behavioural therapy or drugs such as antidepressants. But neither of these is guaranteed to alleviate feelings, and both can take six weeks or more to kick in. Ketamine, a drug being considered as an immediate treatment, can cause hallucinations and its effects wear off quickly. “Having something you could use on your own outside of a hospital would be beneficial,” says Ballard. Jaak Panksepp at Washington State University and his colleagues decided to see whether an opioid can counter suicidal feelings. Opioids are one of the brain’s natural feel-good chemicals. They are released to relieve pain when we hurt ourselves, and are involved when we deal with mental pain, such as that caused by social rejection, a common trigger for suicidal thoughts. © Copyright Reed Business Information Ltd.
By Laurel Hamers As one person at the dinner table leans back, stretches, and opens their mouth in a gaping yawn, others will soon follow suit. Catching a yawn is more likely to occur between relatives than strangers, and scientists believe it’s sign of empathy. Plus, other social primates like chimps and bonobos do it, too. A new study suggests that women (traditionally branded the more empathetic sex) might be more susceptible to copycat yawning than men. Researchers surreptitiously analyzed more than 4000 real-world yawns on planes and trains, in restaurants, and in offices. They noted when someone yawned, and then whether a nearby acquaintance or friend did the same within a 3-minute period. Men and women spontaneously yawned with about the same frequency. But when someone else yawned first, women were more likely than men to follow suit. Women picked up yawns about 55% of the time, whereas men only did so 40% of the time. Women tend to score higher than men on tests of empathy, and traditional female social roles (like child-rearing) place a higher emphasis on those traits. That might make women more attuned to others’ yawns, the researchers suggest. Gender roles aren’t as rigid in our modern society—but the yawning gap appears to linger. © 2016 American Association for the Advancement of Science
By CHARLES SIEBERT Nearly 30 years ago, Lilly Love lost her way. She had just completed her five-year tour of duty as an Alaska-based Coast Guard helicopter rescue swimmer, one of an elite team of specialists who are lowered into rough, frigid seas to save foundering fishermen working in dangerous conditions. The day after she left active service, the helicopter she had flown in for the previous three years crashed in severe weather into the side of a mountain, killing six of her former crewmates. Devastated by the loss and overcome with guilt, Love chose as her penance to become one of the very fishermen she spent much of her time in the Coast Guard rescuing. In less than a year on the job, she nearly drowned twice after being dragged overboard in high seas by the hooks of heavy fishing lines. Love would not formally receive a diagnosis of severe post-traumatic stress disorder for another 15 years. In that time, she was married and divorced three times, came out as transgender and retreated periodically to Yelapa, Mexico, where she lived in an isolated cabin accessible only by water. She eventually ended up living on a boat in a Los Angeles marina, drinking heavily and taking an array of psychotropic drugs that doctors at the West Los Angeles Veterans Administration Medical Center began to prescribe with increasing frequency as Love proved resistant to traditional treatments like counseling and group therapy. One night, after her fifth stay in the center’s psych ward, she crashed her boat into a sea wall. Finally, in 2006, she was in the veterans’ garden and happened to catch sight of the parrots being housed in an unusual facility that opened a year earlier on the grounds of the center. ‘‘This place is why I’m still here,’’ Love, now 54, told me one day last summer as I watched her undergo one of her daily therapy sessions at the facility, known as Serenity Park, a name that would seem an utter anomaly to anyone who has ever been within 200 yards of the place. © 2016 The New York Times Company
Link ID: 21839 - Posted: 01.30.2016
by Helen Thompson Octopus emotions may run skin deep, researchers report January 28 in Current Biology. Changes in octopus skin color primarily function as camouflage, though some evidence points to other purposes. Biologists from Australia and the United States spied on shallow-water octopuses (Octopus tetricus, also known as the gloomy octopus) feeding in Jervis Bay, Australia. Sifting through 52 hours of footage, they saw that the animals adopted a darker hue, stood tall and spread their arms and web when being aggressive or intimidating. Other members of the same species either responded in kind and fought or turned a pale color before swimming away. Skin color changes appear to serve as a form of communication in these conflicts — the first evidence of such an octopus communication system at play in the wild, the researchers assert. The work also challenges the stereotype that octopuses are solitary and antisocial. In Jervis Bay, Australia, a gloomy octopus (Octopus tetricus) displays aggressive behaviors: dark skin color, elevated mantle and spread web. Another octopus approaches and reacts by changing its skin to a pale color before swimming away to avoid conflict. © Society for Science & the Public 2000 - 2016
Link ID: 21836 - Posted: 01.30.2016
By Jane E. Brody. About 15 years ago, I was invited to join a knitting group. My reluctant response — “When would I do that?” — was rejoined with “Monday afternoons at 4,” at a friend’s home not three minutes’ walk from my own. I agreed to give it a try. My mother had taught me to knit at 15, and I knitted in class throughout college and for a few years thereafter. Then decades passed without my touching a knitting needle. But within two Mondays in the group, I was hooked, not only on knitting but also on crocheting, and I was on my way to becoming a highly productive crafter. I’ve made countless afghans, baby blankets, sweaters, vests, shawls, scarves, hats, mittens, caps for newborns and two bedspreads. I take a yarn project with me everywhere, especially when I have to sit still and listen. As I’d discovered in college, when my hands are busy, my mind stays focused on the here and now. It seems, too, that I’m part of a national resurgence of interest in needle and other handicrafts, and not just among old grannies like me. The Craft Yarn Council reports that a third of women ages 25 to 35 now knit or crochet. Even men and schoolchildren are swelling the ranks, among them my friend’s three grandsons, ages 6, 7 and 9. Last April, the council created a “Stitch Away Stress” campaign in honor of National Stress Awareness Month. Dr. Herbert Benson, a pioneer in mind/body medicine and author of “The Relaxation Response,” says that the repetitive action of needlework can induce a relaxed state like that associated with meditation and yoga. Once you get beyond the initial learning curve, knitting and crocheting can lower heart rate and blood pressure and reduce harmful blood levels of the stress hormone cortisol. But unlike meditation, craft activities result in tangible and often useful products that can enhance self-esteem. I keep photos of my singular accomplishments on my cellphone to boost my spirits when needed. © 2016 The New York Times Company
Link ID: 21826 - Posted: 01.27.2016
Richard A. Friedman WHO among us hasn’t wanted to let go of anxiety or forget about fear? Phobias, panic attacks and disorders like post-traumatic stress are extremely common: 29 percent of American adults will suffer from anxiety at some point in their lives. Sitting at the heart of much anxiety and fear is emotional memory — all the associations that you have between various stimuli and experiences and your emotional response to them. Whether it’s the fear of being embarrassed while talking to strangers (typical of social phobia) or the dread of being attacked while walking down a dark street after you’ve been assaulted (a symptom of PTSD), you have learned that a previously harmless situation predicts something dangerous. It has been an article of faith in neuroscience and psychiatry that, once formed, emotional memories are permanent. Afraid of heights or spiders? The best we could do was to get you to tolerate them, but we could never really rid you of your initial fear. Or so the thinking has gone. The current standard of treatment for such phobias revolves around exposure therapy. This involves repeatedly presenting the feared object or frightening memory in a safe setting, so that the patient acquires a new safe memory that resides in his brain alongside the bad memory. As long as the new memory has the upper hand, his fear is suppressed. But if he is re-traumatized or re-exposed with sufficient intensity to the original experience, his old fear will awaken with a vengeance. This is one of the limitations of exposure therapy, along with the fact that it generally works in only about half of the PTSD patients who try it. Many also find it upsetting or intolerable to relive memories of assaults and other traumatizing experiences. © 2016 The New York Times Company
Link ID: 21815 - Posted: 01.23.2016
By Melissa Dahl It’s the fifth inning and the Tampa Bay Rays are beating the Cleveland Indians 6–2 when Cleveland’s relief pitcher Nick Hagadone steps in. Alas, Hagadone does little to turn around the Indians’ luck that day, closing out the long inning with a score of 10–2. Hagadone, apparently frustrated by his own lackluster performance, heads to the clubhouse and, on the way there, punches a door with his left fist — the fist that is, unfortunately, connected to his pitching arm. That momentary impulse would cost him dearly. Hagadone required surgery and eight months’ recovery time — and, to add insult to a literal injury, his team also relegated him to the minor leagues, a move that shrank his annual salary by more than 80 percent. When asked about what could possibly explain an action like this in a usually easy-going guy, the Indians’ team psychologist, Charlie Maher, could only offer variations on this: “He just snapped.” Unless you are also a relief pitcher in the major leagues, you will likely never be in exactly this situation. But how many times have you reacted aggressively, even violently, in a way that felt almost out of your control? You hurl your smartphone across the room, or you unleash a stream of expletives in a manner that would seem to a calmer, rational mind to be disproportionate to the situation at hand. “I just snapped” is how we explain it to ourselves and others, and then we move on. The phrase has become such a cliché that it’s easy to forget that it doesn’t really explain much of anything. What’s behind this impulsive, immediately regrettable behavior? R. Douglas Fields, a senior investigator at the National Institutes of Health, sought out an explanation in his new book, Why We Snap: Understanding the Rage Circuit in Your Brain, which includes the Hagadone story recounted above. © 2016, New York Media LLC
By David Shultz It’s a familiar image: a group monkeys assembled in a line, picking carefully through each other’s hair, eating any treasures they might find. The grooming ritual so common in many primate species serves to both keep the monkeys healthy as well as reinforce social structures and bonds. But according to new research on vervet monkeys (Chlorocebus pygerythrus, seen above), the behavior may also improve a pelt’s insulation by fluffing it up like a duvet, scientists report in the American Journal of Primatology. To test the difference between groomed or ungroomed fur, the team manually combed vervet monkey pelts either with or against the grain for 50 strokes. The fluffed up “backcombed” pelts simulated a recently groomed monkey, whereas the flattened pelts simulated an ungroomed state. Using a spectrophotometer, the researchers then measured how much light was reflected by each pelt and calculated the pelt’s total insulation. They found that a thicker, fluffier coat could improve a monkey’s insulation by up to 50%, keeping the animal warmer in the cold and cooler in the heat. Thus, grooming may help the vervets maintain a constant body temperature with less effort, freeing up more energy for sex, foraging, and participating in monkey society. In the face of climate change, the authors note, such flexibility could soon become enormously important. © 2016 American Association for the Advancement of Science.