Chapter 15. Emotions, Aggression, and Stress

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By Virginia Morell When an adult striped dolphin emerged from the Mediterranean Sea in 2016 pushing, nudging, and circling the carcass of its dead female companion for more than an hour, a nearby boat of scientists fell silent. Afterward, the students aboard said they were certain the dolphin was grieving. But was this grief or some other response? In a new study, researchers are attempting to get to the bottom of a mystery that has plagued behavioral biologists for 50 years. Grief, in humans at least, is a reaction to the permanent severing of a strong social or family bond. Although chimpanzees, baboons, and elephants are thought to experience the complex emotion, scientists don’t yet know enough about it in other animals. There are dozens of photos and YouTube videos of grieflike behavior in dolphins: Some mothers have been seen carrying their dead infants in their mouths or on their backs for a week or longer, even as the body decomposes; a couple adult males have also been seen holding dead calves in their mouths. In the new study, cetacean biologist Giovanni Bearzi of Dolphin Biology and Conservation in Pordenone, Italy, and his colleagues at other institutions analyzed 78 scientific reports from 1970 to 2016 of these kinds of displays—which they labeled “postmortem-attentive behavior.” They found that just 20 of 88 cetacean (dolphin and whale) species engage in them. Of those, most were dolphins from the Sousa and Tursiops genera. Just one was a baleen whale—a humpback. © 2018 American Association for the Advancement of Science.

Keyword: Emotions; Evolution
Link ID: 25110 - Posted: 06.20.2018

By Elizabeth Bauer Ask a roomful of neuroscientists to define the term “emotion” and you will trigger a lively discussion. Some will argue that emotions involve conscious experiences that can be studied only in humans. Others might counter that insects and other invertebrates exhibit some of the emotion building blocks seen in mammals. Some will contend that different emotions correspond to anatomically distinct areas of the brain, whereas others argue that emotions are produced in a highly distributed manner. Still others will bring up the 19th-century psychologist William James’s argument that emotions are a consequence, not a cause, of behavior. In The Neuroscience of Emotion, Ralph Adolphs and David J. Anderson argue that before we can study it, we must first define what we mean by “emotion.” Only then, they maintain, can we form appropriate and testable hypotheses. Colleagues at Caltech, the authors bring different experimental backgrounds to the topic of emotion. Adolphs studies the neural basis of human social behavior. Anderson uses rodents and fruitflies as model organisms to investigate how internal states elicit emotional behaviors. Their book is less a catalog of recent neuroscientific discoveries and more a conceptual framework for investigating emotional behaviors both in humans and in other animals. Adolphs and Anderson begin by contending that emotions are biological phenomena that cause behavioral and physiological changes in the brain and body and—in some species—subjective feelings. If emotions are a class of internal brain states expressed in measurable ways, they argue, we can study the neurobiological implementation of these states separately from subjective conscious feelings, meaning both humans and other animals are potential subjects. They go on to define, in detail, the basic properties of an emotion, including valence, scalability, persistence, automaticity, and generalization. © 2017 American Association for the Advancement of Science.

Keyword: Emotions; Aggression
Link ID: 25109 - Posted: 06.20.2018

Ed Yong Peter, aged 3, was scared of rabbits. So Mary Cover Jones kept bringing him rabbits. At first, she’d take a caged rabbit up to Peter, while he ate some candy and played with other children. At first, Peter was terrified by the mere presence of a rabbit in the same room. But soon, he allowed the animal to get closer—12 feet, then four, then three. Eventually, Peter was happy for rabbits to nibble his fingers. “The case of Peter illustrates how a fear may be removed under laboratory conditions,” Cover Jones wrote in 1924. Cover Jones is now recognized as the "mother of behavioral therapy." Her observations laid the groundwork for what would become known as exposure therapy—the practice of getting people to overcome their fears by facing them in controlled settings. A century later, neuroscientists can watch how the act of facing one’s fears actually plays out inside the brain. Using gene-engineering tools, they can label the exact neurons in a mouse’s brain that store a specific fearful memory. Then, they can watch what happens when the rodent recalls those experiences. By doing this, Ossama Khalaf from the EPFL in Lausanne showed that the extinction of fear depends on reactivating the neurons that encode it. A mouse has to re-experience a deep-rooted fear if it is to lose it. When someone encounters a new experience—say, a terrifying rabbit—groups of neurons in their brain fire together, the connections between them become stronger, and molecules accumulate at the places where neurons meet. Many scientists believe that these preserved patterns of strengthened connections are the literal stuff of memories—the physical representations of the things we remember. These connected neuron groups are called engrams.

Keyword: Emotions; Learning & Memory
Link ID: 25101 - Posted: 06.18.2018

By Diana Kwon In an ischemic stroke a clot blocks a blood vessel to the brain, depriving oxygen and nutrients to part of the crucial organ. Without immediate treatment this can cause irreversible tissue damage, leading to complications ranging from behavioral changes to paralysis. Stroke is the fifth-highest cause of death in the U.S., and the leading cause of long-term disability. Ischemic strokes are the most common type, accounting for more than 80 percent of all cases. Until recently the only treatment available for ischemic stroke was tissue plasminogen activator, or tPA, a protein that can dissolve blood clots if injected up to four and a half hours after stroke onset. Care has improved dramatically in the last few years as advances in thrombectomy—surgical clot removal—have allowed doctors to clear larger blockages and treat patients up to 24 hours after symptoms began. Even after successful clot removal, however, the rush of blood back into the brain and the dying tissue left behind can lead to additional complications such as inflammation. To address this problem, researchers have been searching for more than 30 years for drugs that could protect the brain from damage after an ischemic stroke. More than a thousand compounds have been investigated in animal studies, and many have made it to clinical trials in people—with little success. “It’s been very disappointing for me and hundreds of other investigators that everything seems to work in animals and nothing works in humans,” says Susan Fagan, a clinical pharmacologist at The University of Georgia. “Neuroprotection is a hard nut to crack.” © 2018 Scientific American

Keyword: Stroke; Neuroimmunology
Link ID: 25088 - Posted: 06.14.2018

Darby Saxbe Flinching as a gunshot whizzes past your window. Covering your ears when a police car races down your street, sirens blaring. Walking past a drug deal on your block or a beating at your school. For kids living in picket-fence suburbia, these experiences might be rare. But for their peers in urban poverty, they are all too commonplace. More than half of children and adolescents living in cities have experienced some form of community violence – acts of disturbance or crime, such as drug use, beatings, shootings, stabbings and break-ins, within their neighborhoods or schools. Researchers know from decades of work that exposure to community violence can lead to emotional, social and cognitive problems. Kids might have difficulty regulating emotions, paying attention or concentrating at school. Over time, kids living with the stress of community violence may become less engaged in school, withdraw from friends or show symptoms of post-traumatic stress, like irritability and intrusive thoughts. In short, living in an unsafe community can have a corrosive effect on child development. Few studies, though, have specifically looked at the toll community violence may take on the growing brain. Recently, I studied this question in collaboration with a team of researchers here at the University of Southern California. Our goal: to see whether individuals exposed to more community violence in their early teen years would show differences in the structure and function of their brains in late adolescence. © 2010–2018, The Conversation US, Inc.

Keyword: Aggression; Development of the Brain
Link ID: 25087 - Posted: 06.14.2018

Angus Chen Hunger can trigger cruel words from kind people. A starved dog lover might fantasize about punting the neighbor's Chihuahua that just will not shut up. A puckish but otherwise nice person might snap at a friend, "Bring me the freaking cheesesteak before I flip this TABLE!" They are, in a word, "hangry" or irrationally irritable, upset or angry because of hunger. But how hunger turns into hangriness is a mystery, says Jennifer MacCormack, a doctoral candidate at the University of North Carolina, Chapel Hill in psychology and neuroscience, who wanted to understand the phenomenon. "The mechanism isn't clear on how [hunger] affects your emotions or the exact emotional processes," she says. To find out, she designed some provocative experiments to rile up hungry people. In one of them, MacCormack had 118 undergraduates fast for five hours or more and 118 others eat a meal before coming to her lab. "Psych 101 students, bless their heart," she says. "They didn't know this was a study about feeling hangry." Unfortunately for them, MacCormack concocted an experiment to annoy them and to see how they responded. First, she had half the people in both groups write an essay about emotions to direct their attention to how they're feeling. The other half wrote an essay about a neutral, unemotional day. "We wanted to see if [self-awareness] halts creating this hangry emotions and behaviors," MacCormack says. Next, she had all of them go through a long, arduous computer exercise. "I designed this fake task with colored circles. The colors are really glaring and bright and hard to look at, and it's a hard task with a hundred trials," she says. © 2018 npr

Keyword: Emotions
Link ID: 25076 - Posted: 06.11.2018

Emine Saner One of the fun parts of being a disgustologist – as researchers who study the emotion of disgust sometimes call themselves – must be coming up with revolting scenarios. Repulsive enough to test a theory, but not quite so stomach-turning as to repel the people who have volunteered to take the test. In a recent study led by Prof Val Curtis, director of the environmental health group at the London School of Hygiene and Tropical Medicine, the vignettes were admirably imaginative. People were asked to rate their levels of disgust at more than 70 scenarios. These included imagining a hairless old cat rubbing up against one’s leg, stepping on a slug in bare feet, shaking hands with someone with “scabby fingers”, finding out a friend eats roadkill, finding out another attempted to have sex with a piece of fruit, and seeing “pus come from a genital sore”. And, my personal favourite, for warped imagination alone: learning your neighbour defecates in his back garden. The findings, published this week in the Royal Society’s Philosophical Transactions B journal, reveal six categories of disgust: poor hygiene, animals that are vectors of disease (such as rats or cockroaches), sexual behaviours, atypical appearance, lesions and visible signs of infection, and food that shows signs of decay. “The fact we’ve found there is an architecture of disgust that has six components to it tells us something about the way in which emotions work,” says Curtis. “It tells us that emotions are for doing particular behaviours. The emotion of disgust is about doing certain things that avoid disease – they’re about not eating spoiled food, not sticking your fingers in somebody’s weeping sore, not having sex with somebody you know is having sex with lots of other people, not picking up cockroaches and kissing them. It confirms the hypothesis that disgust really is about avoiding infection.” © 2018 Guardian News and Media Limited

Keyword: Emotions
Link ID: 25060 - Posted: 06.06.2018

By The Editorial Board When President Trump mused that the mass shooting at a high school in Parkland, Fla., in February might have been prevented if the United States had more mental institutions, he revived a not-quite-dormant debate: Should the country bring back asylums? Psychiatric facilities are unlikely to prevent crimes similar to the Parkland shooting because people are typically not committed until after a serious incident. Still, a string of news articles, editorials and policy forums have noted that plenty of mental health experts agree with the president’s broader point. The question of whether to open mental institutions tends to divide the people who provide, use and support mental health services — let’s call them the mental health community — into two camps. There are just 14 or so psychiatric beds per every 100,000 people in the United States, a 95 percent decline from the 1950s. One camp says this profound shortage is a chief reason that so many people suffering from mental health conditions have ended up in jail, on the streets or worse. The other argues that large psychiatric institutions are morally repugnant, and that the problem is not the lack of such facilities but how little has been done to fill the void since they were shut down. Neither side wants to return to the era of “insane asylums,” the warehouselike hospitals that closed en masse between the 1960s and 1980s. Nor does anyone disagree that the “system” that replaced them is a colossal failure. Nearly 10 times as many people suffering from serious mental illnesses are being kept in jails and prisons as are receiving treatment in psychiatric hospitals. What’s more, both sides broadly agree that mental institutions alone would not be the solution. “Bring back the asylums” sounds catchy, but here are some more useful slogans to help steer the conversation: © 2018 The New York Times Company

Keyword: Schizophrenia; Aggression
Link ID: 25056 - Posted: 06.04.2018

Will Stone Hundreds of survivors of domestic violence have come through the doors of neurologist Glynnis Zieman's Phoenix clinic in the past three years. "The domestic violence patients are the next chapter of brain injury," she says. Zieman begins every new patient visit with a simple question: "What are the symptoms you hope I can help you with?" For most, it's the first time anyone has ever asked even how they may have been injured in the first place. "I actually heard one patient tell me the only person who ever asked her if someone did this to her was a paramedic, as she was being wheeled into an ambulance," Zieman says. "And the husband was at the foot of her stretcher." While many patients initially seek out the clinic because of physical symptoms, such as headaches, exhaustion, dizziness or problems sleeping, Zieman says her research shows anxiety, depression and PTSD usually end up being the most severe problems. Studies of traumatic brain injury have revealed links to dementia and memory loss in veterans and athletes. And TBI has also been linked to PTSD in current or former service members. Another group may be suffering, still largely in silence — survivors of domestic violence. About 70 percent of people seen in the ER for such abuse are never actually identified as survivors of domestic violence. It's a health crisis cloaked in secrecy and shame, one that Zieman is uncovering through her work at the Barrow Concussion and Brain Injury Center. © 2018 npr

Keyword: Brain Injury/Concussion; Aggression
Link ID: 25051 - Posted: 06.02.2018

Some human brains are nearly twice the size of others – but how might that matter? Researchers at the National Institute of Mental Health (NIMH) and their NIH grant-funded colleagues have discovered that these differences in size are related to the brain’s shape and the way it is organized. The bigger the brain, the more its additional area is accounted for by growth in thinking areas of the cortex, or outer mantle – at the expense of relatively slower growth in lower order emotional, sensory, and motor areas. This mirrors the pattern of brain changes seen in evolution and individual development – with higher-order areas showing greatest expansion. The researchers also found evidence linking the high-expanding regions to higher connectivity between neurons and higher energy consumption. “Just as different parts are required to scale-up a garden shed to the size of a mansion, it seems that big primate brains have to be built to different proportions,” explained Armin Raznahan, M.D., Ph.D., of the NIMH Intramural Research Program (IRP). “An extra investment has to be made in the part that integrates information – but that’s not to say that it’s better to have a bigger brain. Our findings speak more to the different organizational needs of larger vs. smaller brains.” Raznahan, P.K. Reardon, Jakob Seidlitz, and colleagues at more than six collaborating research centers report on their study incorporating brain scan data from more than 3,000 people in Science. Reardon and Seidlitz are students in the NIH Oxford-Cambridge Scholars Program.

Keyword: Attention; Evolution
Link ID: 25045 - Posted: 06.01.2018

Imagine having superhuman hearing. You’re at a noisy, cocktail party and yet your ears can detect normally inaudible sounds made by your friends’ muscles as they lean in to dish the latest gossip. But, unlike normal hearing, each of these sounds causes your ears to react in the same way. There is no difference between the quietest and loudest movements. To your superhuman ears, they all sound loud, like honking horns. According to a study funded by the National Institutes of Health, that may be how a shark’s electrosensing organ reacts when it detects teensy, tiny electrical fields emanating from nearby prey. “Sharks have this incredible ability to pick up nanoscopic currents while swimming through a blizzard of electric noise. Our results suggest that a shark’s electrosensing organ is tuned to react to any of these changes in a sudden, all-or-none manner, as if to say, ‘attack now,’” said David Julius, Ph.D., professor and chair of physiology at the University of California, San Francisco and senior author of the study published in Nature. His team studies the cells and molecules behind pain and other sensations. For instance, their results have helped scientists understand why chili peppers feel hot and menthol cool. Led by post-docs Nicholas W. Bellono, Ph.D. and Duncan B. Leitch, Ph.D., Dr. Julius’ team showed that the shark’s responses may be very different from the way the same organ reacts in skates, the flat, winged, evolutionary cousins of sharks and sting rays, and this may help explain why sharks appear to use electric fields strictly to locate prey while skates use them to find food, friends, and mates. They also showed how genes that encode for proteins called ion channels may control the shark’s unique “sixth sense.”

Keyword: Aggression; Pain & Touch
Link ID: 25038 - Posted: 05.31.2018

Alison Abbott Depression affects one in four people at some time in their lives. It is often difficult to treat, in part because its causes are still debated. Psychiatrist Edward Bullmore is an ardent proponent of a radical theory now gaining traction: that inflammation in the brain may underlie some instances. His succinct, broad-brush study, The Inflamed Mind, looks at the mounting evidence. The book outlines a persuasive case for the link between brain inflammation and depression. Bullmore pleads with the medical profession to open its collective mind, and the pharmaceutical industry to open its research budget, to the idea. He provides a current perspective on how the science of psychiatry is slowly emerging from a decades-long torpor. He sees the start of a shift in the Cartesian view that disorders of the body ‘belong’ to physicians, whereas those of the more ‘immaterial’ mind ‘belong’ to psychiatrists. Accepting that some cases of depression result from infections and other inflammation-causing disorders of the body could lead to much-needed new treatments, he argues. In 1989, during his clinical training at St Bartholomew’s Hospital in London, Bullmore encountered a patient whom he calls Mrs P, who had severe rheumatoid arthritis. She left an indelible impression. He examined her physically and probed her general state of mind. He reported to his senior physician, with a certain pride in his diagnostic skill, that Mrs P was both arthritic and depressed. Replied the experienced rheumatologist dismissively, given her painful, incurable physical condition, “You would be, wouldn’t you?” © 2018 Macmillan Publishers Limited,

Keyword: Depression; Neuroimmunology
Link ID: 25036 - Posted: 05.30.2018

By Kashmira Gander Scientists have turned off aggressive behavior in mice for weeks at a time by harnessing the power of a little-understood group of brain cells. In a new study, which sheds light on the potential biological cause of aggression, scientists tinkered with neurons in the brains of lab mice. To arrive at their findings, the researchers at the Karolinska Institutet in Sweden investigated the role of a set of neurons in the ventral premammillary nucleus (PMv) of the hypothalamus. Mice generally resort to aggression as a way to assert their dominance rather than cause harm, so the scientists tested their hypothesis using the so-called tube test. This involves pitting two mice against each other in a narrow corridor, in order to document their responses in this socially fraught situation. The study, published in the journal Nature Neuroscience, showed when male mice were confronted with a new male in their home cage, the animals responded aggressively, and showed activity in the PMv neurons. Using a technique where neurons are turned on and off using light, called optogenetics, the researchers were also able to trigger aggressive behavior in mice in scenarios where they were usually calm. In turn, they could stop a mouse mid-attack by turning off the light. What's more, when a generally submissive male was faced with a dominant male, blocking the PMv cells inverted their statuses. As well as aggression, PMv neurons also appeared to be associated with other parts of the brain—the part linked to rewards. © 2018 Newsweek LLC

Keyword: Aggression
Link ID: 25030 - Posted: 05.29.2018

By Victoria Gill Science correspondent, BBC News Scientists working with dolphins at a marine park near Paris have attempted to measure how the animals feel about aspects of their lives in captivity. In what researchers say is the first project to examine captivity "from the animals' perspective", the team assessed what activities dolphins looked forward to most. They found that the marine mammals most keenly anticipated interacting with a familiar human. The results, they say, show that "better human-animal bonds equals better welfare". The study, published in the journal Applied Animal Behaviour Science, was part of a three-year project to measure dolphin welfare in a captive setting. Lead researcher Dr Isabella Clegg worked at Parc Astérix, a theme park with one of France's largest dolphinariums. With colleagues at the University of Paris animal behaviour lab, she designed experiments to decode dolphin behaviour - essentially looking for physical postures that indicate how the animals were feeling. "We wanted to find out what activities in captivity they like most," Dr Clegg told the BBC. To work this out, she tested three activities: a trainer coming and playing with dolphins; adding toys to the pool; and a control, which meant leaving the dolphins to their own devices. "We found a really interesting result - all dolphins look forward most to interacting with a familiar human," Dr Clegg said. The animals showed this anticipation by "spy hopping", the action of peering above the surface and looking in the direction that trainers usually approached from. The dolphins would also increase their level of activity in the pool and spend more time at the edge. "We've seen this same thing in other zoo animals and in farm animals," said Dr Clegg, adding: "Better human-animal bonds equals better welfare." © 2018 BBC.

Keyword: Animal Rights; Emotions
Link ID: 25028 - Posted: 05.29.2018

Hartmut Wekerle Some immunologists regard the central nervous system (CNS) as a no-man’s-land, avoided by immune cells and therefore uninteresting. But, in fact, the CNS has a vigorous immune potential that remains dormant in normal conditions but is awakened after injury. The switch that controls the brain’s immune microenvironment involves non-neuronal cells called glia — not only microglia, which are sometimes called the immune cells of the CNS, but also multifunctional cells called astrocytes1. In a paper in Nature, Rothhammer et al.2 describe how these two glial cell types communicate on a molecular level to influence inflammation in the CNS, and show that this interaction is controlled remotely by microbes that inhabit the gut. A decade ago, the group that performed the current study, along with another research group, discovered3,4 an unexpected immunoregulatory role for a ligand-activated transcription factor called the aryl hydrocarbon receptor (AHR), which at the time was best known as a receptor for environmental toxins5. The two groups showed that AHR modulates the progression of experimental autoimmune encephalomyelitis (EAE) — an autoimmune disease in mice in which the immune system becomes overactive and attacks the CNS. EAE is often used a model of multiple sclerosis (MS). Initially, the groups focused on how AHR might affect EAE by regulating pathogenic and protective subsets of immune cells outside the CNS. But it later emerged that AHR is also strongly expressed in the CNS, particularly in microglia and astrocytes6, raising the question of whether AHR in the CNS has a role in autoimmune diseases. © 2018 Macmillan Publishers Limited,

Keyword: Neuroimmunology; Obesity
Link ID: 25010 - Posted: 05.23.2018

Nicola Davis Many people complain they do not get enough sleep, and it seems they are right to be concerned. Researchers have found that adults under the age of 65 who get five or fewer hours of sleep for seven days a week have a higher risk of death than those who consistently get six or seven hours’ shut-eye. However the effect of short sleeps over a few days may be countered by a later lie-in. The research found that individuals who managed just a few hours’ sleep each day during the week but then had a long snooze at weekends had no raised mortality risk, compared with those who consistently stuck to six or seven hours a night. “Sleep duration is important for longevity,” said Torbjörn Åkerstedt, first author of the study, at the Stress Research Institute, Stockholm University, and Karolinska Institute, also in the Swedish capital. The study, published in the Journal of Sleep Research, is based on data from more than 38,000 adults, collected during a lifestyle and medical survey conducted throughout Sweden in 1997. The fate of participants was followed for up to 13 years, using a national death register. Åkerstedt said researchers had previously looked at links between sleep duration and mortality but had focused on sleep during the working week. “I suspected there might be some modification if you included also weekend sleep, or day-off sleep.” Once factors such as gender, body mass index, smoking, physical activity and shift work, were taken into account, the results revealed that those under the age of 65 who got five hours of sleep or under that amount seven days a week had a 65% higher mortality rate than those getting six or seven hours’ sleep every day. But there was no increased risk of death for those who slept five or fewer hours during the week but then managed eight or more hours’ sleep on weekend days. 'Western society is chronically sleep deprived': the importance of the body's clock © 2018 Guardian News and Media Limited

Keyword: Sleep; Neuroimmunology
Link ID: 25007 - Posted: 05.23.2018

By Abdul-Kareem Ahmed “Dad, hold still.” As we entered the hospital room that morning, our patient’s daughter was attempting to give him a shave. He was bed-bound after his operation and had grown a salt-and-pepper stubble. A week earlier, his wife had brought him to the emergency room . He was behaving oddly, mumbling nonsensical sentences and stumbling through the house. Sixty-two years old, male, Caucasian, new and profound neurological symptoms. An M.R.I. of his brain seemed redundant but confirmed the diagnosis: A four-centimeter malignant tumor was invading his right frontal cortex, the seat of his personality, where “Dad” lived. I’m drawn to the human brain, its unforgiving and protean nature. Just five minutes without oxygen, and the brain loses function. The occipital cortex processes visual information and allows us to see faces, trees, the stars. However, in a young child who becomes blind, as with Helen Keller, this same cortex can be repurposed for entirely distinct functions, like language processing. Early astronomers looked to the heavens for answers. But in the human brain, a three-pound ball of fat, there resides enough mystery and potential to have satisfied Galileo, Kepler and Brahe. And so I found myself, on what had now been a four-year foray toward a career in neurosurgery, helping care for this patient. I was the sub-intern at a hospital away from home for the month. It was my first week on the job. The resident and I stood around his bed in our cerulean scrubs and white coats and watched him smiling. His daughter looked toward me, the only other male in the room, and paused, razor in hand. © 2018 The New York Times Company

Keyword: Emotions
Link ID: 24985 - Posted: 05.17.2018

In a study of mice, National Institutes of Health-funded researchers describe a new circuit involved in fine-tuning the brain’s decision either to hide or confront threats. The study, published in Nature, was partially funded by the NIH’s Brain Research through Advancing Innovative Neurotechnologies (BRAIN) Initiative. “Being able to manipulate specific circuits can uncover surprising relationships between brain areas and provide great insight into how the sensory, emotional, and behavioral centers work together to drive reactions,” said Jim Gnadt, Ph.D., program director at the NIH’s National Institute of Neurological Disorders and Stroke (NINDS) and a team lead for the BRAIN Initiative. “The tools and technologies developed through the BRAIN Initiative have made studies such as this one possible.” A team of researchers led by Andrew Huberman, Ph.D., professor of neurobiology and of ophthalmology at Stanford University in California, investigated the role of the ventral midline thalamus (vMT) in determining how animals respond to visual threats. The thalamus is a brain region that acts as a relay station, taking in sensory information, such as what is seen and heard, and sorting out where in the brain to send that information. Dr. Huberman and his colleagues showed that the vMT was activated when mice were confronted with a threat, specifically a black circle that grew larger on top of their cage, mimicking the experience of something looming over them. When faced with the looming threat, the mice spent most of the time freezing or hiding and very little time rattling their tails, which is typically an aggressive response.

Keyword: Emotions; Aggression
Link ID: 24962 - Posted: 05.11.2018

Susan Milius Pick an animal. Choose wisely because in this fantasy you’ll transform into the creature and duel against one of your own. If you care about survival, go for the muscular, multispiked stag roaring at a rival. Never, ever pick the wingless male fig wasp. Way too dangerous. This advice sounds exactly wrong. But that’s because many stereotypes of animal conflict get the real biology backward. All-out fighting to the death is the rule only for certain specialized creatures. Whether a species is bigger than a breadbox has little to do with lethal ferocity. Many creatures that routinely kill their own kind would be terrifying, if they were larger than a jelly bean. Certain male fig wasps unable to leave the fruit they hatch in have become textbook examples, says Mark Briffa, who studies animal combat. Stranded for life in one fig, these males grow “big mouthparts like a pair of scissors,” he says, and “decapitate as many other males as they possibly can.” The last he-wasp crawling has no competition to mate with all the females in his own private fruit palace. In contrast, big mammals that inspire sports-team mascots mostly use antlers, horns and other outsize male weaponry for posing, feinting and strength testing. Duels to the death are rare. |© Society for Science & the Public 2000 - 2018.

Keyword: Aggression
Link ID: 24944 - Posted: 05.05.2018

Greg Chapman, research scientist, Boston University Twin Project Humans have succeeded as a species in large part because of our ability to cooperate and coordinate with each other. These skills are driven by a range of “moral emotions” such as guilt and empathy, which help us to navigate the nuance of social interactions appropriately. Those who lack moral emotions are classed as having “callous-unemotional” traits: persistent personality characteristics that make negotiating social situations difficult. The combination of callous-unemotional traits and antisocial behaviour in adolescents and adults is typically diagnosed as psychopathy. Moral emotions can be measured in children as young as three. Persistent personality traits aren’t measured in children this young, but recent research has begun to explore whether repeated callous-unemotional behaviours might be evident even in preschoolers. Such behaviours include parental observations that punishment doesn’t change behaviour, that the child shows little affection toward people and seems unresponsive to affection from others. At least half of children who exhibit callous-unemotional behaviours will naturally grow out of them. Only if they persist into adolescence do they become classified by psychiatrists as persistent personality traits. However, callous-unemotional behaviours in a young child in combination with other risk factors can be a warning sign for later social difficulties and behaviour disorders. For instance, callous-unemotional behaviours in early childhood have been shown to predict aggressive behaviours, attention deficit hyperactivity disorder and oppositional defiant disorder and are a risk factor for later psychopathy.

Keyword: Development of the Brain; Genes & Behavior
Link ID: 24939 - Posted: 05.05.2018