Chapter 11. Emotions, Aggression, and Stress
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An Ontario researcher has discovered that common male crickets talk trash, dance and brag after winning a fight. The discovery has caught the attention of fellow researchers and National Geographic magazine. Lauren Fitzsimmons, a Natural Sciences and Engineering Research Council postdoctoral research fellow at the University of Windsor, discovered the brash behaviour. Fitzsimmons placed pairs of male crickets in a small, clear arena, which always led to fights. The arena included a viewing area for other crickets. She set up three audience situations: a male watching and listening to a fight, a female watching and listening to a fight, or no audience. The combatants bit, pushed and flipped each other around the ring. "After a series of these bouts, one male will kind of sulk away and not interact anymore, while the other will perform a song and dance," Fitzsimmons said. She said the winning cricket would "shake his body back and forth" and chirp in victory. "When we had a male audience watching, the male would produce more of these victory displays," Fitzsimmons said. "The speculation is they can tell there is another individual there, and they’re showing off. "We know females prefer dominant males and males who win fights." © CBC 2013
The lifetime rate of diagnosis of anxiety disorders is higher in women, with 33 percent experiencing an anxiety disorder in their lifetime, as compared with 22 percent of men. Experts believe this difference arises from a combination of hormonal fluctuations, brain chemistry and upbringing: women more often feel responsible for the happiness of others, such as their children or their spouse. © 2013 Scientific American
By JAN HOFFMAN From the shock of the cancer diagnosis onward, depression can take its well-documented toll on patients. Even patients who appear to pack away their fears during the grinding treatment journey to becoming cancer-free concede that when the regimen ends, they unspool emotionally. There has been less attention paid to the disease’s emotional impact on spouses. They, too, can become depressed. But with the roles of caregiver and cheerleader thrust upon them, they may feel constrained about expressing their darker feelings. Now a new analysis finds that within two years of a cancer diagnosis, the pervasiveness of depression in patients and their spouses tends to drop back to roughly the same levels as in the general population, only to be replaced by another mind-demon: anxiety, which can even intensify as time passes. 48 Were you a caretaker for someone with cancer? How did you take care of yourself while your partner was going through treatment? Join in the discussion below. The analysis, which looked at 43 studies involving 51,381 patients with a range of cancers, found that over all, nearly 18 percent of patients experienced serious anxiety two to 10 years after their diagnosis, compared with about 14 percent of the general population. But in a cluster of studies that looked at couples, anxiety levels in that time frame grew to as high as 28 percent in patients and 40 percent in their spouses. Copyright 2013 The New York Times Company
Link ID: 18372 - Posted: 07.13.2013
by Emily Underwood "Antibrain" antibodies that slip through the placenta from mother to fetus during pregnancy may account for roughly a quarter of autism cases, a new study suggests. Some scientists say the work could lead to a blood test that accurately predicts whether a mother will bear a child with this immune-triggered form of the disorder—a claim that's raising eyebrows among skeptics. Autism spectrum disorder (ASD), a range of communication and social deficits estimated to affect 1 in 88 children, is now largely thought to be a neurodevelopmental malady that begins in the womb. For years, many researchers have brushed aside the idea that an out-of-whack immune response could contribute to this, preferring to focus on genetic factors that could derail typical brain development, says immunologist Judy Van de Water. Over the past decade, however, she and her colleagues at the University of California (UC), Davis, as well as several other research groups, have been slowly building a case for the role of an immune disorder in a subset of autism cases. "We just didn't quit," she says. In 2008, Van de Water found that roughly a quarter of 61 women with autistic children carried in their blood an unusual group of antibodies—large, Y-shaped proteins with sticky ends that normally bind to and destroy foreign or potentially harmful microbes. Some of these, called autoantibodies, occasionally go rogue and attack the body's healthy cells, causing autoimmune diseases such as lupus and rheumatoid arthritis. The higher the level of autoantibodies in the mother's blood, the more severe the child's autistic symptoms, Van de Water observed. She hypothesized that these autoantibodies were attacking proteins necessary for fetal brain development. © 2010 American Association for the Advancement of Science
By Kate Wong In the July issue of Scientific American, anthropologist Barbara King of The College of William & Mary makes the case that animals ranging from ducks to dolphins may grieve when a relative or close companion dies. In so doing she departs from a long-standing tradition among animal behaviorists of assiduously avoiding projecting human emotions onto other animals. Not all animal responses to death qualify as mourning, however. King is careful to establish criteria for grief, noting that “researchers may strongly suspect grief only when certain conditions are met: First, two (or more) animals choose to spend time together beyond survival-oriented behaviors such as foraging or mating. Second, when one animal dies, the survivor alters his or her normal behavioral routine—perhaps reducing the amount of time devoted to eating or sleeping, adopting a body posture or facial expression indicative of depression or agitation, or generally failing to thrive.” Here King describes two recent, well-publicized examples of animal reactions to death that illustrate the challenges of interpreting such behaviors: “Occasionally the pull of anthropomorphism may overwhelm scientists’ normal caution in reporting animal responses to death. When Teresa Iglesias of the University of California at Davis and her colleagues published a paper in Animal Behaviour last year entitled ‘Western scrub jay funerals: cacophonous aggregations in response to dead conspecifics,’ the news media responded enthusiastically to the notion of a bird funeral. Yet nothing like a caretaking ritual around jay bodies actually had been observed. From a series of experiments, the scientists had discovered that scrub jays respond by vocalizing upon sighting the bodies of dead companions; they seem to be communicating information to their flock mates about potential risks in the environment. Iglesias told me last year, for my post about her paper at NPR.org’s 13.7 blog, that ‘funeral’ is an apt term ‘only to the extent that it is an animal paying attention to another dead animal’ (and excluding behaviors such as scavenging). Any of the animal examples discussed in this article would, on this definition, quality as a ‘funeral,’ a too-generous application of the term.” © 2013 Scientific American
A UC Berkeley study suggests that sleep deprivation triggers anxiety by inducing hyperactivity in brain regions that control emotions. The study, published in the Journal of Neuroscience, suggests that sleep therapy can help patients with anxiety disorders. Stress and anticipation bring anxiety that can sometimes be good; if under control, anxiety might help a person focus and be more efficient. But a patient with anxiety disorders, such as post-traumatic stress disorder (PTSD), generalized anxiety disorder (GAD), obsessive-compulsive disorder (OCD) or other disorders and phobias, cannot control it. The feeling of anxiety and nervousness is constant and has major negative impact on their everyday life. The socioeconomic impact is huge as about one in five adults in the U.S. are affected by such mental illnesses. What are the drivers of anxiety disorders? Why can some people control anxiety while others cannot? Research studies have shown over the years that causes can be genetics, personality, social environment and brain chemistry. Scientists have found a network of neurons in the brain that supports affective anticipation and anxiety. More precisely, those with anxiety disorders have hyperactivity in certain regions of the brain that process emotions, including the amygdala and anterior insula cortex. On top of that, sleep deprivation amplifies the symptoms, a setback for patients because it is very common for them to suffer from sleep abnormalities. Looking for more clues about the connection between sleep and anxiety management, Matthew P. Walker, professor of psychology and neuroscience at UC Berkeley, led a study that looked for differences in the activity of the amygdala and anterior insula cortex in the brains of healthy adults after sleep deprivation and after a good night’s sleep.
By GRETCHEN REYNOLDS In an eye-opening demonstration of nature’s ingenuity, researchers at Princeton University recently discovered that exercise creates vibrant new brain cells — and then shuts them down when they shouldn’t be in action. For some time, scientists studying exercise have been puzzled by physical activity’s two seemingly incompatible effects on the brain. On the one hand, exercise is known to prompt the creation of new and very excitable brain cells. At the same time, exercise can induce an overall pattern of calm in certain parts of the brain. Most of us probably don’t realize that neurons are born with certain predispositions. Some, often the younger ones, are by nature easily excited. They fire with almost any provocation, which is laudable if you wish to speed thinking and memory formation. But that feature is less desirable during times of everyday stress. If a stressor does not involve a life-or-death decision and require immediate physical action, then having lots of excitable neurons firing all at once can be counterproductive, inducing anxiety. Studies in animals have shown that physical exercise creates excitable neurons in abundance, especially in the hippocampus, a portion of the brain known to be involved in thinking and emotional responses. But exercise also has been found to reduce anxiety in both people and animals. How can an activity simultaneously create ideal neurological conditions for anxiety and leave practitioners with a deep-rooted calm, the Princeton researchers wondered? So they gathered adult mice, injected them with a substance that marks newborn cells in the brain, and for six weeks, allowed half of them to run at will on little wheels, while the others sat quietly in their cages. Copyright 2013 The New York Times Company
By Cristy Gelling Lemur species that live in large groups can tell when to steal food from a competitor in a lab experiment, researchers report June 26 in PLOS ONE. The finding supports the idea that brainpower in primates evolved to fit their complex social lives. Because the sneakier lemurs don't have bigger brains than less sneaky ones living in smaller groups, researchers suggest that social smarts don’t always depend on brain size. Much of the evidence for sociality’s role in the evolution of intelligence comes from indirect measures such as brain size, says study coauthor Evan MacLean of Duke University. But brain size does not always correspond to brainpower, so MacLean uses behavioral tests. He and his colleagues tested the social intelligence of six species of lemur, primates from Madagascar distantly related to monkeys and apes. Each of the species lives in social groups ranging from families of just three, mongoose lemurs’ preferred posse, to gangs of about 16, a typical size for a group of ring-tailed lemurs. The researchers trained lemurs to view humans as competitors for food, then presented the animals with a choice between pilfering treats from one of two people: one facing the animals or another with his or her back turned. Species that live in small groups reached for the food under a competitor’s nose as often as they did behind people’s backs. But the ring-tailed lemurs were much more likely to choose the unguarded food. © Society for Science & the Public 2000 - 2013
Male twin Vietnam veterans with post-traumatic stress disorder (PTSD) were more than twice as likely as those without PTSD to develop heart disease during a 13-year period, according to a study supported by the National Institutes of Health. This is the first long-term study to measure the association between PTSD and heart disease using objective clinical diagnoses combined with cardiac imaging techniques. “This study provides further evidence that PTSD may affect physical health,” said Gary H. Gibbons, M.D., director of the NIH's National Heart, Lung, and Blood Institute (NHLBI), which partially funded the study. “Future research to clarify the mechanisms underlying the link between PTSD and heart disease in Vietnam veterans and other groups will help to guide the development of effective prevention and treatment strategies for people with these serious conditions.” The findings appear online today in the Journal of the American College of Cardiology and in the September 10 print issue. Researchers from the Emory University Rollins School of Public Health in Atlanta, along with colleagues from other institutions, assessed the presence of heart disease in 562 middle-aged twins (340 identical and 222 fraternal) from the Vietnam Era Twin Registry. The incidence of heart disease was 22.6 percent in twins with PTSD (177 individuals) and 8.9 percent in those without PTSD (425 individuals). Heart disease was defined as having a heart attack, having an overnight hospitalization for heart-related symptoms, or having undergone a heart procedure. Nuclear scans, used to photograph blood flow to the heart, showed that individuals with PTSD had almost twice as many areas of reduced blood flow to the heart as individuals without PTSD.
Traci Watson When it comes to friendship it may be quantity, not quality, that matters — at least for Barbary macaques in a crisis. Scientists have long known that sociable humans live longer than their solitary peers, but is the same true for animals? A harsh natural experiment may offer some answers. It also raises intriguing questions about the type of social ties that matter. Endangered Barbary macaques (Macaca sylvanus) in the mountains of Morocco are accustomed to cold, but the 2008–09 winter was devastatingly hard for them. Snow covered the ground for almost four months instead of the usual one, and the monkeys, which eat seeds and grasses on the ground, began to starve. Richard McFarland, a behavioural ecologist at the University of the Witwatersrand in Johannesburg, South Africa, and his colleagues were studying the animals as part of a wider project on the monkeys' social lives launched in January 2008. When they went looking for the macaques in January 2009, they found corpses, says McFarland. Of the 47 adults in two troops that the team studied, only 17 survived, making for a 64% mortality rate, McFarland and his colleague Bonaventura Majolo of the University of Lincoln, UK, report today in Biology Letters1. Analysis showed that the more friends a monkey had, the more likely it was to have survived. Individuals with whom a monkey had exchanged grooming or had had bodily contact with at least once during observation sessions were deemed as social contacts. Perhaps the animals with more buddies had more partners with whom to huddle against the cold, the researchers suggest. Monkeys with large social networks may also have been able to look for food with fewer interruptions from hostile group members. © 2013 Nature Publishing Group
By Melissa Hogenboom Science reporter, BBC News The social brain theory - that animals in large social groups have bigger brains - has now been supported by a computer model. For animals in smaller social groups, the cost of having a large brain outweighs the benefits. Scientists used a simulation modelling technique to confirm that large social groups are only possible through sophisticated communication. The study is published in Proceedings of the Royal Society B. The human brain is a very costly organ which consumes a lot of energy. Animals that live in small social groups could therefore be at a disadvantage if they had large brains taking up processing power that could better be used elsewhere. A team at Oxford University has now looked at the cognitive demands of making social decisions using a method called agent-based modelling, which models simplified representations of reality. As expected, they found that more complex social decisions take up more 'brain' power. The cognitive complexity of language evolved as social groups became larger and more complex, said lead author of the study Tamas David-Barrett from the University of Oxford. He explained that a group of five is an ideal number to coordinate an event such as a hunt, but as the group size increases, the coordination involved would become increasingly complex. BBC © 2013
The paralyzing syndrome Guillain-Barré syndrome isn't linked to receiving common vaccines, according to a U.S. study. Concerns about the association of Guillain-Barré syndrome with vaccines have "flourished" since there was a hint of an increased risk after the 1976 swine flu vaccine campaign. It hasn’t been clearly linked since then. The syndrome is an acute inflammatory disease that results in destruction of a nerve’s myelin sheath and some nerves, which in severe cases can progress to complete paralysis and even death. Researchers from the U.S. Centers for Disease Control and Prevention and Kaiser Permanente Vaccine Study Center in Oakland, Calif. looked back at cases of GBS over 13 years in the state that were confirmed by a neurologist who reviewed the medical records. In the 13-year study period 415 patients were confirmed with GBS only 25 had received a vaccine within six weeks before onset of the disease. "In summary, this study did not find any association between influenza vaccine or any other vaccine and development of GBS within six weeks following vaccination," Dr. Roger Baxter, co-director of the Kaiser Permanente Vaccine Study Center and his co-authors concluded in Monday's online issue of Clinical Infectious Diseases. © CBC 2013
Maggie Fox, NBC News Researchers have figured out how to read your mind and tell whether you are feeling sad, angry or disgusted – all by looking at a brain scan. The experiment, using 10 acting students, showed people have remarkably similar brain activity when experiencing the same emotions. And a computer could predict how someone was feeling just by looking at the scan. The findings could be used to help treat patients with various mental health conditions, and even provide a hard, medical diagnosis for emotional disorders. It might also be used to get a window into the minds of people with developmental disorders such as autism, the researchers at Carnegie Mellon University in Pittsburgh say. And one big, immediate application – testing advertisements. “What emotion do you want to evoke with your ad for the latest BMW?” said psychology professor Marcel Just, who helped oversee the study. "This research introduces a new method with potential to identify emotions without relying on people's ability to self-report," added Karim Kassam, assistant professor of social and decision sciences at CMU, who led the study. "It could be used to assess an individual's emotional response to almost any kind of stimulus, for example, a flag, a brand name or a political candidate."
By Arielle Duhaime-Ross Rats don't usually come out into daylight, especially not on a busy morning in New York City. But there it was, head awkwardly jutting out in front of its body, swinging from side to side. What injured the creature, I have no idea, but its hind legs could no longer support its weight. The rat dragged them like a kid drags a garbage bag that parents have asked be taken out–reluctantly. The muscles in the front legs rippled as they propelled the body forward along the sidewalk. The rodent was surprisingly quick considering the injury. But its aimlessness suggested distress. Two girls, no more than 15 years old, spotted the wounded rat from about 10 feet away. They held each other close, squealing and giggling, inching toward the animal theatrically. Staring them down, I scowled. How could they not appreciate this creature’s suffering or be touched by its desperation? I looked on, saying nothing. In The Last Child in the Woods, journalist Richard Louv talks about "nature deficit disorder," something we urbanites have picked up over the last hundred years or so. He says that city-dwellers have become so disconnected from nature that they cannot process the harsh realities of the natural world, like the sight of an injured animal. But if those young women were suffering from urban disconnection, then why didn’t I—a city slicker through and through—react that way as well? What made me respond with empathy instead of disgust? Evolutionary theorists believe that many of our behaviors are adaptive in some way. "Empathy probably started out as a mechanism to improve maternal care," says Frans de Waal, a primatologist at Emory University and author of The Age of Empathy. "Mammalian mothers who were attentive to their young’s needs were more likely to rear successful offspring." © 2013 Scientific American
By Scicurious When I am stressed (and I’m stressed a lot of the time, as I bet a lot of you are as well), I turn to coffee. Not just to keep me going through the time when I need to get things done, but also for relaxation. For me, the smell and taste of coffee brings me thoughts of relaxing conversations with friends and other fun times. But what if the memories weren’t all the relaxing the caffeine was doing for me? What if the chronic caffeine consumption was keeping my stressful life at bay? It’s time to look at adenosine 2A receptors in the hippocampus. Don’t worry, the coffee will be back. First let’s talk about stress. Specifically, childhood stress. In small doses, stress exposure can actually be good for you, but in large, or prolonged, doses, it’s definitely not. There are effects immediately after stress, as well as long term ones. when you suffer strong stressors in development, you can end up with changes all the way into adulthood, from cognitive deficits to predisposition to psychiatric disorders. Why is stress in development so important? During development, our brains are developing too, particularly our hippocampus. While the hippocampus is best known for its role in memory and spatial navigation, it’s also extremely important in emotional responses. Neuronal growth in the hippocampus can come from enriched environments or chronic antidepressants, and death of those neurons can come from chronic stress. Chronic stress also disrupts the hypothalamic-pituitary-adrenal axis (the HPA axis) And that’s just in adults! During development, animals are very susceptible to stress, and the hippocampus is still developing its connections. And we’re still figuring out what changes occur during early life stress and how they relate to behaviors in adulthood. © 2013 Scientific American
By James Gallagher Health and science reporter, BBC News An experimental treatment to stop the body attacking its own nervous system in patients with multiple sclerosis (MS) appears safe in trials. The sheath around nerves cells, made of myelin, is destroyed in MS, leaving the nerves struggling to pass on messages. A study on nine patients, reported in Science Translational Medicine, tried to train the immune system to cease its assault on myelin. The MS Society said the idea had "exciting potential". As nerves lose their ability to talk to each other, the disease results in problems moving and balancing and can affect vision. There are drugs that can reduce number and severity of attacks, but there is no cure. The disease is caused by the body's immune system thinking that myelin is a foreign body like a flu virus. Researchers at the Northwestern University Feinberg School of Medicine developed a technique to retrain the immune system. They took blood samples and coupled white blood cells, a part of the immune system, to fragments of myelin. This was injected back into the patients to make them tolerate myelin. BBC © 2013
By Piercarlo Valdesolo The posed stare-down is a staple of the pre-fight ritual. Two fighters, one day removed from attempting to beat the memories from each other, stand impossibly close, raise their clenched fists and fix their gaze on the other’s eyes as cameras click away. This has always seemed little more than a vehicle for media hype, but new research from psychologists at the University of Illinois suggests that there may be clues in this bit of theatre that predict the results of the fight to come. Specifically, the researchers hypothesized that there’s something about the fighters’ facial expressions in this standoff that reveal the competitive dynamics between them. A subtle, and perhaps unintentional, communication of submission from one fighter to the other. A recognition of the opponent’s power. The smile. Facial expressions have long been thought to be reliable indicators of a person’s true feelings. Indeed, in his book “The Expression of the Emotions in Man and Animals” Darwin suggested that such expressions have evolved precisely because they serve this important function. The smile has attracted much empirical attention and has generally been interpreted as a signal of an individuals’ immediate, as well as long-term, well-being. In a particularly interesting study, the frequency and “authenticity” of smiles in high school yearbook photos tended to predict higher levels of subjective well-being years later. But smiles can mean different things in different contexts. The researchers here were particularly interested in what a smile might mean when displayed between competitors. Instead of merely communicating a fighter’s good spirits, the researchers hypothesized that it would be a submissive signal that reveals a fighter’s reduced hostility and lower willingness to aggress towards the opponent. © 2013 Scientific American,
By Felicity Muth If you grew up with brothers or sisters you will know that competition is a key part of childhood. Personally, I experienced competition for food resources (the last bar of chocolate), parental investment (attention) and other more unusual resources (the best colour of lego pieces). As we age, we continue competing, although what we compete for changes. We compete in sports, for partners and for jobs. Like humans, pretty much all other animals will compete in one way or another. Even if they live a solitary life they may be still competing indirectly with others. But, like humans, animals need to choose which battles are worth fighting, and how much effort to put into it. One obvious way of deciding when to bother competing with another is the absolute worth of the thing you’re fighting over. If you and a stranger stumbled across some money in the street, you might fight vigorously for a $100 note, but more half-heartedly for $5 (this is of course an example using some very money-driven and aggressive individuals). However, how much value an individual puts on an item’s worth is going to be somewhat subjective. If you’re poor and starving, you might invest more into fighting for $5 than someone who is not. Thus, most competitions will contain both objective and subjective aspects: the intrinsic worth of an object (large food items are better than small), and the individual’s state when they’re assessing that item. © 2013 Scientific American
Link ID: 18225 - Posted: 06.04.2013
By JENNA WORTHAM ON a recent family outing, my mother and sister got into a shouting match. But they weren’t mad at each other — they were yelling at the iPhone’s turn-by-turn navigation system. I interrupted to say that the phone didn’t understand — or care — that they were upset. “Honey, we know,” my mom replied. “But it should!” She had a point. After all, computers and technology are becoming only smarter, faster and more intuitive. Artificial intelligence is creeping into our lives at a steady pace. Devices and apps can anticipate what we need, sometimes even before we realize it ourselves. So why shouldn’t they understand our feelings? If emotional reactions were measured, they could be valuable data points for better design and development. Emotional artificial intelligence, also called affective computing, may be on its way. But should it be? After all, we’re already struggling to cope with the always-on nature of the devices in our lives. Yes, those gadgets would be more efficient if they could respond when we are frustrated, bored or too busy to be interrupted, yet they would also be intrusive in ways we can’t even fathom today. It sounds like a science-fiction movie, and in some ways it is. Much of this technology is still in its early stages, but it’s inching closer to reality. Companies like Affectiva, a start-up spun out of the M.I.T. Media Lab, are working on software that trains computers to recognize human emotions based on their facial expressions and physiological responses. A company called Beyond Verbal, which has just raised close to $3 million in venture financing, is working on a software tool that can analyze speech and, based on the tone of a person’s voice, determine whether it indicates qualities like arrogance or annoyance, or both. © 2013 The New York Times Company
by Paul Gabrielsen Take a whiff, men. A chemical component of other guys' sweat makes men more cooperative and generous, new research says. The study is the first to show that this pheromone, called androstadienone, influences other men's behavior and reinforces the developing finding that humans are susceptible and responsive to these chemical signals. Pheromones are everywhere in the animal world. Bugs in particular give off these chemicals to sound an alarm, identify a food source, or attract a mate. And smitten animals may indeed have "chemistry" together—pheromone signals are a subconscious part of their communication. Scientists didn't know if humans played that game as well. But in the last 30 years, they've identified both male and female putative pheromones that are linked to mood and reproductive cycles. Some fragrancemakers have even incorporated them into their products, hoping to add an extra emotional punch to colognes and perfumes. Real-life pheromones don't smell so nice, however: The specialized glands that produce these chemical compounds are located near the armpit, where they mix with sweat. Previous investigations focused on the chemicals as sexual attractants—studying a male pheromone's effect on female mood and behavior, for example. Turns out that women aren't the only ones susceptible to the power of male pheromones. Evolutionary biologist Markus Rantala of the University of Turku in Finland crafted an experiment in which 40 men in their mid-20s played a computer game in which two players decided how to share €10. One player offers a possible split, and the other decides whether to accept or reject it. Each participant took a turn making or deciding on offers. © 2010 American Association for the Advancement of Science