Links for Keyword: Aggression

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Judith Ohikuare In 2005, James Fallon's life started to resemble the plot of a well-honed joke or big-screen thriller: A neuroscientist is working in his laboratory one day when he thinks he has stumbled upon a big mistake. He is researching Alzheimer's and using his healthy family members' brain scans as a control, while simultaneously reviewing the fMRIs of murderous psychopaths for a side project. It appears, though, that one of the killers' scans has been shuffled into the wrong batch. The scans are anonymously labeled, so the researcher has a technician break the code to identify the individual in his family, and place his or her scan in its proper place. When he sees the results, however, Fallon immediately orders the technician to double check the code. But no mistake has been made: The brain scan that mirrors those of the psychopaths is his own. After discovering that he had the brain of a psychopath, Fallon delved into his family tree and spoke with experts, colleagues, relatives, and friends to see if his behavior matched up with the imaging in front of him. He not only learned that few people were surprised at the outcome, but that the boundary separating him from dangerous criminals was less determinate than he presumed. Fallon wrote about his research and findings in the book The Psychopath Inside: A Neuroscientist's Personal Journey Into the Dark Side of the Brain, and we spoke about the idea of nature versus nurture, and what—if anything—can be done for people whose biology might betray their behavior. © 2017 by The Atlantic Monthly Group.

Related chapters from BP7e: Chapter 15: Emotions, Aggression, and Stress
Related chapters from MM:Chapter 11: Emotions, Aggression, and Stress
Link ID: 23707 - Posted: 06.05.2017

By Elizabeth Pennisi When, 6 years ago, divers captured on video a cuckolding attempt among squidlike animals called cuttlefish, experts were stunned. “The violence was beyond anything we had ever seen in the laboratory,” says Roger Hanlon, an ecologist at the Marine Biological Laboratory in Woods Hole, Massachusetts, who had been studying captive cuttlefish for years. Now, by carefully analyzing the behavior of the two males involved, he and his colleagues suggest the stepwise escalation of their fight likely required more brainpower than many researchers thought invertebrates had, they report this week in American Naturalist. The video (above) first shows a common European male cuttlefish (Sepia officinalis) mating with a female. While he escorts her to where she will lay her eggs, a second male suddenly appears and chases him away. But the first male doesn’t give up, and as his rival starts to get fresh with the female, the scuffle gets ever more intense. The rivals squirt ink at each other and jet about. Then, their dark markings turn even darker, and they engage in a quick battle of biting, grappling, and cork-screwing that soon sends the intruder scurrying off. Now that the scientists know how such explosive situations come about, they hope to recreate those circumstances in the lab to study male rivalries more systematically. © 2017 American Association for the Advancement of Science. A

Related chapters from BP7e: Chapter 15: Emotions, Aggression, and Stress; Chapter 12: Sex: Evolutionary, Hormonal, and Neural Bases
Related chapters from MM:Chapter 11: Emotions, Aggression, and Stress; Chapter 8: Hormones and Sex
Link ID: 23564 - Posted: 05.04.2017

By Gareth Cook The carnivore needs no introduction: fearsome, cold and brutal. But G. A. Bradshaw, known for her psychological work with elephants, asks readers to reconsider. In “Carnivore Minds,” she argues that predators are none of these things. She uses the orca for a case study in the evolution of morals; to explore emotional intelligence, her main example is the crocodile. Through “trans-species psychology,” Bradshaw asks us to consider the many ways that the animals we fear are far more similar to us than we might like to think. She answered questions from Mind Matters editor Gareth Cook. What first lead you to explore the minds of carnivores? Carnivores are a natural counterpoint to the herbivorous elephant, the subject of my previous book, Elephants on the Edge. There certainly are differences between white sharks and elephants, but the similarities are much greater. We know this because of what neuroscience has discovered — mammals, birds, fish, and reptiles (and now, it appears, invertebrates like bees and octopi) share common brain structures and processes that govern thinking and feeling. The scientific model used to explore human minds applies to other animals. This trans-species psychology allows us to see, even experience, the worlds of carnivores as they might — from the inside-out. White sharks, coyotes, and wolves not only have comparable mental and emotional capacities as humans, they are equally vulnerable to psychological trauma. This is what I discovered with the diagnosis of post-traumatic stress disorder (PTSD) in wild elephants. When elephants lose their homes and families, are subjected to mass killing, and are captured and incarcerated in zoos, they breakdown mentally and culturally and exhibit symptoms found in human prisoners and victims of genocide. As a result of hunting and persecution, pumas are showing symptoms of complex PTSD. © 2017 Scientific American

Related chapters from BP7e: Chapter 15: Emotions, Aggression, and Stress
Related chapters from MM:Chapter 11: Emotions, Aggression, and Stress
Link ID: 23449 - Posted: 04.05.2017

Bruce Bower Chimps with little social status influence their comrades’ behavior to a surprising extent, a new study suggests. In groups of captive chimps, a method for snagging food from a box spread among many individuals who saw a low-ranking female peer demonstrate the technique, say primatologist Stuart Watson of the University of St. Andrews in Fife, Scotland, and colleagues. But in other groups where an alpha male introduced the same box-opening technique, relatively few chimps copied the behavior, the researchers report online February 7 in the American Journal of Primatology. “I suspect that even wild chimpanzees are motivated to copy obviously rewarding behaviors of low-ranking individuals, but the limited spread of rewarding behaviors demonstrated by alpha males was quite surprising,” Watson says. Previous research has found that chimps in captivity more often copy rewarding behaviors of dominant versus lower-ranking group mates. The researchers don’t understand why in this case the high-ranking individuals weren’t copied as much. The spread of new behaviors in groups of monkeys and apes depends on a variety of factors — including an innovator’s social status, age and sex — that can interact in unpredictable ways. “That’s why social learning in groups is so interesting to study,” says Elizabeth Lonsdorf, a primatologist at Franklin & Marshall College in Lancaster, Pa., who did not participate in the research. |© Society for Science & the Public 2000 - 2017.

Related chapters from BP7e: Chapter 15: Emotions, Aggression, and Stress; Chapter 19: Language and Hemispheric Asymmetry
Related chapters from MM:Chapter 11: Emotions, Aggression, and Stress; Chapter 15: Brain Asymmetry, Spatial Cognition, and Language
Link ID: 23269 - Posted: 02.22.2017

By Chelsea Whyte It was a gruesome scene. The body had severe wounds and was still bleeding despite having been lying for a few hours in the hot Senegalese savanna. The murder victim, a West African chimpanzee called Foudouko, had been beaten with rocks and sticks, stomped on and then cannibalised by his own community. This is one of just nine known cases where a group of chimpanzees has killed one of their own adult males, as opposed to killing a member of a neighbouring tribe. These intragroup killings are rare, but Michael Wilson at the University of Minnesota says they are a valuable insight into chimp behaviour such as male coalition building. “Why do these coalitions sometimes succeed, but not very often? It’s at the heart of this tension between conflict and cooperation, which is central to the lives of chimpanzees and even to our own,” he says. Chimps usually live in groups with more adult females than males, but in the group with the murder it was the other way round. “When you reverse that and have almost two males per every female — that really intensifies the competition for reproduction. That seems to be a key factor here,” says Wilson. Jill Pruetz at Iowa State University, who has been studying this group of chimpanzees in south-eastern Senegal since 2001, agrees. She suggests that human influence may have caused this skewed gender ratio that is likely to have been behind this attack. In Senegal, female chimpanzees are poached to provide infants for the pet trade. Fall from power Thirteen years ago, Foudouko reigned over one of the chimp clans at the Fongoli study site, part of the Fongoli Savanna Chimpanzee Project. As alpha male, he was “somewhat of a tyrant”, Pruetz says. © Copyright Reed Business Information Ltd.

Related chapters from BP7e: Chapter 15: Emotions, Aggression, and Stress; Chapter 12: Sex: Evolutionary, Hormonal, and Neural Bases
Related chapters from MM:Chapter 11: Emotions, Aggression, and Stress; Chapter 8: Hormones and Sex
Link ID: 23174 - Posted: 02.01.2017

Jon Hamilton Mice that kill at the flip of a switch may reveal how hunting behavior evolved hundreds of millions of years ago. The mice became aggressive predators when two sets of neurons in the amygdala were activated with laser light, a team reported Thursday in the journal Cell. "The animals become very efficient in hunting," says Ivan de Araujo, an associate professor of psychiatry at Yale University and an associate fellow at The John B. Pierce Laboratory in New Haven. "They pursue the prey [a live cricket] faster and they are more capable of capturing and killing it." Activating the neurons even caused the mice to attack inanimate objects, including sticks, bottle caps and an insectlike toy. "The animals intensively bite the toy and use their forepaws in an attempt to kill it," De Araujo says. But the aggressive behavior is reserved for prey. Mice didn't attack each other, even when both sets of neurons were activated. The results hint at how the brain changed hundreds of millions of years ago when the first animals with jaws began to appear. This new ability to pursue and kill prey "must have influenced the way the brain is wired up in a major way," De Araujo says. Specifically, the brain needed to develop hunting circuits that would precisely coordinate the movements of a predator's jaw and neck. "This is a very complex and demanding task," De Araujo says. © 2017 npr

Related chapters from BP7e: Chapter 15: Emotions, Aggression, and Stress
Related chapters from MM:Chapter 11: Emotions, Aggression, and Stress
Link ID: 23099 - Posted: 01.13.2017

By Andy Coghlan Is the fabled “cuddle hormone” really a “warmone”? Oxytocin levels surge in troops of chimpanzees preparing for conflict with rival groups to defend or expand their territory. The finding is at odds with the prevailing image of oxytocin as something that helps strengthen bonds between parent and infant, or foster friendships. But given its capacity to strengthen loyalty, oxytocin could also be a warmonger hormone that helps chimps galvanise and cooperate against a common enemy. Catherine Crockford of the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, and her colleagues monitored two rival groups of chimpanzees in the Taï National Park in Ivory Coast, each containing five males and five females, for prolonged periods between October 2013 and May 2015. Thanks to trust built up between the team and the chimps, the team could safely track and video the groups – even during conflict, observing at close quarters what was happening. Crucially, the team was also able to pipette up fresh samples from soil when chimps urinated. The samples revealed that oxytocin levels surge in the mammals whenever the chimps on either side prepared for confrontation, or when either group took the risk of venturing near or into rival-held territories. These surges dwarfed the oxytocin levels seen during activities such as grooming, collaborative hunting for monkey prey or food sharing. © Copyright Reed Business Information Ltd.

Related chapters from BP7e: Chapter 5: Hormones and the Brain; Chapter 15: Emotions, Aggression, and Stress
Related chapters from MM:Chapter 8: Hormones and Sex; Chapter 11: Emotions, Aggression, and Stress
Link ID: 23065 - Posted: 01.07.2017

By Chloé Hecketsweiler Can brain science predict when someone will commit a crime, or tell whether a defendant knew right from wrong? In recent decades, scientists and criminal justice experts have been trying to answer tantalizing questions like these — with mixed success. The science of predicting crime using algorithms is still shaky, and while sophisticated tools such as neuroimaging are increasingly being used in courtrooms, they raise a host of tricky questions: What kind of brain defect or brain injury should count when assessing a defendant’s responsibility for a crime? Can brain imaging distinguish truth from falsehood? Can neuroscience predict human behavior? Judith Edersheim, an assistant professor of psychiatry at Harvard Medical School and also a lawyer who specializes in forensic evaluations, focuses her research on these gray areas. In 2009, she co-founded the Center for Law, Brain, and Behavior at Massachusetts General Hospital, with the goal of “translating neuroscience into the legal arena.” And on December 15, at an event at Brigham and Women’s Hospital in Boston, Edersheim will talk about the vulnerability of the aging brain, highlighting the case of a man affected by an undetected brain disease. For this installment of the Undark Five, we asked her what brain imaging can reveal about the “criminal brain,” how relationships between brain functioning and behavior can inform the courtroom, and what controversies this iconoclastic science may raise. Questions and answers have been edited for length and clarity, and Undark has supplied some additional links. UNDARK — Using brain imaging, scientists have identified correlations between certain brain abnormalities and criminal behaviors. Is there a signature for the “criminal brain”? JUDITH EDERSHEIM — There may be no criminal minds; there may be criminal moments. Copyright 2016 Undark

Related chapters from BP7e: Chapter 15: Emotions, Aggression, and Stress; Chapter 2: Functional Neuroanatomy: The Nervous System and Behavior
Related chapters from MM:Chapter 11: Emotions, Aggression, and Stress; Chapter 2: Cells and Structures: The Anatomy of the Nervous System
Link ID: 22978 - Posted: 12.12.2016

By Brian Owens Cooperation makes it happen. Sailfish that work together in groups to hunt sardines can catch more fish than if they hunt alone, even without a real coordinated strategy. To catch their sardine dinner, a group of sailfish circle a school of sardines – known as a baitball – and break off a small section, driving it to the surface. They then take turns attacking these sardines, slashing at them with their long sword-like bills, which account for a quarter of their total length of up to 3.5 metres. Knocking their prey off-balance makes them easier to grab. These attacks only result in a catch about 25 per cent of the time, but they almost always injure several sardines. As the number of injured fish increases, it becomes ever easier for everyone to snag a meal. “There’s no coordination, no strict turn-taking or specific hunting roles, it’s opportunistic,” says James Herbert-Read, from Uppsala University in Sweden. But Herbert-Reads computer models now show that even this rudimentary form of cooperation is better than going it alone. Sailfish that work in groups capture more sardines than a lone fish would get in the same amount of time. © Copyright Reed Business Information Ltd

Related chapters from BP7e: Chapter 15: Emotions, Aggression, and Stress; Chapter 6: Evolution of the Brain and Behavior
Related chapters from MM:Chapter 11: Emotions, Aggression, and Stress
Link ID: 22819 - Posted: 11.02.2016

By Andy Coghlan More men inevitably means more testosterone-fuelled violence, right? Wrong, according to a comprehensive analysis exploring how a surplus of men or women affect crime rates across the US. In areas where men outnumber women, there were lower rates of murders and assaults as well as fewer sex-related crimes, such as rapes, sex offences and prostitution. Conversely, higher rates of these crimes occurred in areas where there were more women than men. Ryan Schacht of the University of Utah in Salt Lake City and his colleagues analysed sex ratio data from all 3082 US counties, provided by the US Census Bureau in 2010. They compared this with crime data for the same year, issued by the US Federal Bureau of Investigation. They only included information about women and men of reproductive age. For all five types of offence analysed, rising proportions of men in a county correlated with fewer crimes– even when accounting for other potential contributing factors such as poverty. The results suggest that current policies aimed at defusing violence and crime by reducing the amount of men in male-dominated areas may backfire. According to Schacht, when women are in short supply, men must be more dutiful to win and retain a partner. With an abundance of women, men are spoilt for choice and adopt more promiscuous behaviour that brings them into conflict with other men, and more likely to commit sex-related offences. © Copyright Reed Business Information Ltd.

Related chapters from BP7e: Chapter 15: Emotions, Aggression, and Stress; Chapter 12: Sex: Evolutionary, Hormonal, and Neural Bases
Related chapters from MM:Chapter 11: Emotions, Aggression, and Stress; Chapter 8: Hormones and Sex
Link ID: 22731 - Posted: 10.08.2016

Rebecca Hersher A new study of violent behavior in more than 1,000 mammal species found the meerkat is the mammal most likely to be murdered by one of its own kind. The study, led by José María Gómez of the University of Grenada in Spain and published Wednesday in the journal Nature, analyzed more than 4 million deaths among 1,024 mammal species and compared them with findings in 600 studies of violence among humans from ancient times until today. The findings tell us two things: Some amount of violence between humans is attributable to our place on the evolutionary tree. Meerkats are surprisingly murderous. To be clear, the study's authors did not set out to prove (or disprove) a theory of meerkat violence; they were investigating what mammalian data might tell us about humans. But Ed Yong at The Atlantic organized the study's exhaustive list of mammals to make this helpful chart ranking animals by their murderousness. Some of the animals with reputations for docility are actually more dangerous to each other than creatures known for their aggression. Chinchillas kill each other more often than brown bears turn on their own kind. New Zealand sea lions are more murderous than actual lions. And, as you can see, about 20 percent of meerkat deaths are murders. Their violence has been documented; a 2006 study described in National Geographic documented meerkat mothers killing the offspring of other females to maintain dominance. © 2016 npr

Related chapters from BP7e: Chapter 15: Emotions, Aggression, and Stress
Related chapters from MM:Chapter 11: Emotions, Aggression, and Stress
Link ID: 22707 - Posted: 09.29.2016

By NATALIE ANGIER The female bonobo apes of the Wamba forest in the Democratic Republic of Congo had just finished breakfast and were preparing for a brief nap in the treetops, bending and crisscrossing leafy branches into comfortable day beds. But one of the females was in estrus, her rump exceptionally pink and swollen, and four males in the group were too excited to sleep. They took turns wildly swinging and jumping around the fertile female and her bunkmates, shaking the branches, appearing to display their erections and perforating the air with high-pitched screams and hoots. Suddenly, three older, high-ranking female bonobos bolted up from below, a furious blur of black fur and swinging limbs and, together with the female in estrus, flew straight for the offending males. The males scattered. The females pursued them. Tree boughs bounced and cracked. Screams on all sides grew deafening. Three of the males escaped, but the females cornered and grabbed the fourth one — the resident alpha male. He was healthy, muscular and about 18 pounds heavier than any of his captors. But no matter. The females bit into him as he howled and struggled to pull free. Finally, “he dropped from the tree and ran away, and he didn’t appear again for about three weeks,” said Nahoko Tokuyama, of the Primate Research Institute at Kyoto University in Japan, who witnessed the encounter. When the male returned, he kept to himself. Dr. Tokuyama noticed that the tip of one of his toes was gone. “Being hated by females,” she said in an email interview, “is a big matter for male bonobos.” The toe-trimming incident was extreme but not unique. Describing results from their long-term field work in the September issue of Animal Behaviour, Dr. Tokuyama and her colleague Takeshi Furuichi reported that the female bonobos of Wamba often banded together to fend off male aggression, and in patterns that defied the standard primate rule book. © 2016 The New York Times Company

Related chapters from BP7e: Chapter 15: Emotions, Aggression, and Stress; Chapter 12: Sex: Evolutionary, Hormonal, and Neural Bases
Related chapters from MM:Chapter 11: Emotions, Aggression, and Stress; Chapter 8: Hormones and Sex
Link ID: 22641 - Posted: 09.10.2016

By Virginia Morell Infanticide—the killing of offspring—is generally rare among birds. And when it happens, it’s usually because of outsiders that want the nesting site or territory. But what happens among birds, such as the greater ani (Crotophaga major, pictured), which have a more socialist approach to nesting? Two to four pairs of the Central and South American cuckoos (which are usually unrelated) build a single nest, and then work together to raise their chicks, which generally hatch at the same time. Intriguingly, the adults cannot recognize either their own eggs or chicks, so they care for all of them. To find out why—and if the simultaneous hatching protects the chicks from infanticide—a scientist analyzed data on nestling mortality gathered at 104 communal greater ani nests from 2006 to 2015. Of the 741 nestlings, 321 (43%) fledged and 420 (57%) died. Most of the deaths (78.5%) were due to predation. But another 13.8%, or 58 nestlings, died from infanticide, the scientist reports online today in Evolution. The remaining 32 (7.7%) died from starvation. At most of the nests, the chicks hatched within 1 day of each other. Those that first emerged from their eggs were the most likely to be dispatched by one of the nest founders, not an outsider. Chicks that hatched last were also unlucky; weaker than their older and larger nest-mates, they weren’t able to compete for food and starved. Those two pressures—infanticide and food competition—end up favoring the chicks in the middle and those that hatch on the same day, the researcher reports. © 2016 American Association for the Advancement of Science

Related chapters from BP7e: Chapter 6: Evolution of the Brain and Behavior; Chapter 15: Emotions, Aggression, and Stress
Related chapters from MM:Chapter 11: Emotions, Aggression, and Stress
Link ID: 22435 - Posted: 07.14.2016

By Gary Stix Bullies often like being bullies—and an entire line of research links aggressive behaviors to brain areas tied to sensations of reward—sites deep below the organ’s surface with names like the ventromedial hypothalamus and the extended amygdala. One lingering puzzle is what precedes the aggressive act. What makes a person—or, in this case, a mouse—lash out? A new study, published June 29 in Nature, shows that the thought of being the aggressor simply feels good to certain animals. I had a fascinating talk this week with Scott Russo from the Icahn School of Medicine at Mount Sinai, the paper’s senior author, who described the significance of these findings. What did your study find? We discovered a brain circuit—connecting the basal forebrain and lateral habenula—that appears to control the motivation of a male mouse to be aggressive and subordinate another male mouse. The significance of these findings is that the circuit seems to be telling an animal that subordinating, or “bullying,” another animal is a rewarding behavior. To test this, we adapted a conditioned place preference protocol—often used to measure the rewarding properties of addictive drugs, whereby mice were allowed to attack an intruder mouse within one of two environmental contexts: When asked which of the two environmental contexts they preferred, aggressive mice chose the environment in which they were allowed to attack the intruder mouse over the environment in which they had no access to the intruder mouse. Interestingly, the basal forebrain and lateral habenula have been previously shown to support conditioned place preference to drugs of abuse, such as nicotine and cocaine, suggesting that similar neural processes mediate rewarding aspects of aggression and addictive substances. © 2016 Scientific American

Related chapters from BP7e: Chapter 15: Emotions, Aggression, and Stress
Related chapters from MM:Chapter 11: Emotions, Aggression, and Stress
Link ID: 22380 - Posted: 06.30.2016

By Perri Klass, M.D. In the 1990s, in my first month in practice as a pediatrician, I asked the mother of a 4-year-old about discipline and she told me that her son was often out of line and wild, and spanking was the only thing that worked, though she was sure I was going to tell her not to, just as her previous pediatrician had done. Around the same time, my colleague in the same clinic walked into an exam room to find a cranky toddler who was acting out, and a frustrated father who was taking off his belt and threatening punishment. In each case, and in many others, we had to decide how to talk to the parents, and whether to bring up the issue of child abuse — which is definitely an issue when a child is being struck, or threatened, with a belt. Corporal punishment, also known as “physical discipline,” has become illegal in recent decades in many countries, starting with Sweden in 1979. The United States is not one of those countries, and pediatricians regularly find ourselves talking with parents about why hitting children is a bad idea. The American Academy of Pediatrics officially recommends against physical discipline, saying that evidence shows it is ineffective and puts children at risk for abuse; pediatricians are mandated reporters, responsible for notifying the authorities if we think there is a possibility of abuse, though the boundaries are not clearly defined by law. But many parents continue to spank, even when they don’t think it does much good. In a recent report by the nonprofit organization Zero to Three of a national sample of 2,200 parents of children birth to age 5, parents were asked which discipline strategies they used a few times a week or more. Twenty-six percent said they “pop or swat” their child, 21 percent spank, and 17 percent reported hitting with an object like a belt or a wooden spoon. (Parents could respond that they used more than one strategy.) Zero to Three reported that even those who used these strategies frequently did not rate them as effective, and 30 percent agreed with the statement, “I spank even though I don’t feel O.K. about it.” © 2016 The New York Times Company

Related chapters from BP7e: Chapter 15: Emotions, Aggression, and Stress; Chapter 7: Life-Span Development of the Brain and Behavior
Related chapters from MM:Chapter 11: Emotions, Aggression, and Stress; Chapter 13: Memory, Learning, and Development
Link ID: 22362 - Posted: 06.27.2016

Ian Sample Science editor Brain scans have highlighted “striking” differences between the brains of young men with antisocial behavioural problems and those of their better-behaved peers. The structural changes, seen as variations in the thickness of the brain’s cortex or outer layer of neural tissue, may result from abnormal development in early life, scientists at Cambridge University claim. But while the images show how the two groups of brains differ on average, the scans cannot be used to identify individuals with behavioural issues, nor pinpoint specific developmental glitches that underpin antisocial behaviour. Led by Luca Passamonti, a neurologist at Cambridge, the researchers scanned the brains of 58 young men aged 16 to 21 who had been diagnosed with conduct disorder, defined by persistent problems that ranged from aggressive and destructive behaviour, to lying and stealing, carrying weapons or staying out all night. When compared with brain scans from 25 healthy men of the same age, the scientists noticed clear differences. Those diagnosed with conduct disorder before the age of 10 had similar variations in the thickness of the brain’s cortex. “It may be that problems they experience in childhood affect and delay the way the cortex is developing,” said Passamonti. But the brains of men diagnosed with behavioural problems in adolescence differed in another way. Scans on them showed fewer similarities in cortical thickness than were seen in the healthy men. That, Passamonti speculates, may arise when normal brain maturation, such as the “pruning” of neurons and the connections between them, goes awry. © 2016 Guardian News and Media Limited

Related chapters from BP7e: Chapter 15: Emotions, Aggression, and Stress; Chapter 7: Life-Span Development of the Brain and Behavior
Related chapters from MM:Chapter 11: Emotions, Aggression, and Stress; Chapter 13: Memory, Learning, and Development
Link ID: 22329 - Posted: 06.16.2016

By JAMES GORMAN This summer’s science horror blockbuster is a remake: Return of the Leaping Electric Eel! If you have any kind of phobia of slimy, snakelike creatures that can rise from the water and use their bodies like Tasers, this story — and the accompanying video — may not be for you. The original tale (there was, alas, no video) dates to 1800 when the great explorer Alexander von Humboldt was in South America and enlisted local fishermen to catch some of these eels for the new (at the time) study of electricity. He wrote that the men herded horses and mules into a shallow pond and let the eels attack by pressing themselves against the horses. The horses and mules tried to escape, but the fishermen kept them in the water until the eels used up their power. Two horses died, probably from falling and drowning. Or so Humboldt said. Though the story was widely retold, no other report of this kind of fishing-with-horses phenomenon surfaced for more than 200 years, according to Kenneth Catania, a scientist with a passion for studying the eel species in question, electrophorus electricus. In 2014, he reported on how the eels freeze their prey. They use rapid pulses of more than 600 volts generated by modified muscle cells and sent through the water. These volleys of shocks cause the muscles of prey to tense at once, stopping all movement. The eels’ bodies function like Tasers, Dr. Catania wrote. But they can also project high-voltage pulses in the water in isolated couplets rather than full volleys for a different effect. The pairs of shocks don’t freeze the prey, but cause their bodies to twitch. That movement reveals the prey’s location, and then the eels send out a rapid volley to immobilize then swallow it. Dr. Catania noticed another kind of behavior, however. He was using a metal-handled net — wearing rubber gloves — while working with eels in an aquarium, and the eels would fling themselves up the handle of the net, pressing themselves to the metal and generating rapid electric shocks. © 2016 The New York Times Company

Related chapters from BP7e: Chapter 15: Emotions, Aggression, and Stress; Chapter 3: Neurophysiology: The Generation, Transmission, and Integration of Neural Signals
Related chapters from MM:Chapter 11: Emotions, Aggression, and Stress; Chapter 3: Neurophysiology: The Generation, Transmission, and Integration of Neural Signals
Link ID: 22295 - Posted: 06.07.2016

Philip Ball James Frazer’s classic anthropological study The Golden Bough1 contains a harrowing chapter on human sacrifice in rituals of crop fertility and harvest among historical cultures around the world. Frazer describes sacrificial victims being crushed under huge toppling stones, slow-roasted over fires and dismembered alive. Frazer’s methods of analysis wouldn't all pass muster among anthropologists today (his work was first published in 1890), but it is hard not to conclude from his descriptions that what industrialized societies today would regard as the most extreme psychopathy has in the past been seen as normal — and indeed sacred — behaviour. In almost all societies, killing within a tribe or clan has been strongly taboo; exemption is granted only to those with great authority. Anthropologists have suspected that ritual human sacrifice serves to cement power structures — that is, it signifies who sits at the top of the social hierarchy. The idea makes intuitive sense, but until now there has been no clear evidence to support it. In a study published in Nature2, Joseph Watts, a specialist in cultural evolution at the University of Auckland in New Zealand, and his colleagues have analysed 93 traditional cultures in Austronesia (the region that loosely embraces the many small and island states in the Pacific and Indonesia) as they were before they were influenced by colonization and major world religions (generally in the late 19th and early 20th centuries). © 2016 Nature Publishing Group

Related chapters from BP7e: Chapter 15: Emotions, Aggression, and Stress; Chapter 6: Evolution of the Brain and Behavior
Related chapters from MM:Chapter 11: Emotions, Aggression, and Stress
Link ID: 22070 - Posted: 04.05.2016

Brendan Maher It took less than a minute of playing League of Legends for a homophobic slur to pop up on my screen. Actually, I hadn't even started playing. It was my first attempt to join what many agree to be the world's leading online game, and I was slow to pick a character. The messages started to pour in. “Pick one, kidd,” one nudged. Then, “Choose FA GO TT.” It was an unusual spelling, and the spaces may have been added to ease the word past the game's default vulgarity filter, but the message was clear. Online gamers have a reputation for hostility. In a largely consequence-free environment inhabited mostly by anonymous and competitive young men, the antics can be downright nasty. Players harass one another for not performing well and can cheat, sabotage games and do any number of things to intentionally ruin the experience for others — a practice that gamers refer to as griefing. Racist, sexist and homophobic language is rampant; aggressors often threaten violence or urge a player to commit suicide; and from time to time, the vitriol spills beyond the confines of the game. In the notorious 'gamergate' controversy that erupted in late 2014, several women involved in the gaming industry were subjected to a campaign of harassment, including invasions of privacy and threats of death and rape. League of Legends has 67 million players and grossed an estimated US$1.25 billion in revenue last year. But it also has a reputation for toxic in-game behaviour, which its parent company, Riot Games in Los Angeles, California, sees as an obstacle to attracting and retaining players. © 2016 Nature Publishing Group

Related chapters from BP7e: Chapter 15: Emotions, Aggression, and Stress; Chapter 17: Learning and Memory
Related chapters from MM:Chapter 11: Emotions, Aggression, and Stress; Chapter 13: Memory, Learning, and Development
Link ID: 22048 - Posted: 03.30.2016

Rich Stanton In 1976, the driving simulation Death Race was removed from an Illinois amusement park. There had, according to a news story at the time, been complaints that it encouraged players to run over pedestrians to score points. Through a series of subsequent newspaper reports, the US National Safety Council labelled the game “gross” and motoring groups demanded its removal from distribution. The first moral panic over video game violence had begun. This January, a group of four scholars published a paper analysing the links between playing violent video games at a young age and aggressive behaviour in later life. The titles mentioned in the report are around 15-years-old – one of several troubling ambiguities to be found in the research. Nevertheless, the quality and quantity of the data make this an uncommonly valuable study. Given that game violence remains a favoured bogeyman for politicians, press and pressure groups, it should be shocking that such a robust study of the phenomenon is rare. But it is, and it’s important to ask why. A history of violence With the arrival of Pong in 1973, video games became a commercial reality, but now, in 2016, they are still on the rocky path to mass acceptance that all new media must traverse. The truth is that the big targets of moral concern – Doom, Grand Theft Auto, Call of Duty – are undeniably about killing and they are undeniably popular among male teenagers. An industry report estimates that 80% of the audience for the Call of Duty series is male, and 21% is aged 10-14. Going by the 18 rating on the last three entries, that means at least a fifth of the game’s vast audience shouldn’t be playing. © 2016 Guardian News and Media Limited

Related chapters from BP7e: Chapter 15: Emotions, Aggression, and Stress; Chapter 7: Life-Span Development of the Brain and Behavior
Related chapters from MM:Chapter 11: Emotions, Aggression, and Stress; Chapter 13: Memory, Learning, and Development
Link ID: 21970 - Posted: 03.09.2016