Links for Keyword: Aggression

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By John Bohannon If you had the choice between hurting yourself or someone else in exchange for money, how altruistic do you think you’d be? In one infamous experiment, people were quite willing to deliver painful shocks to anonymous victims when asked by a scientist. But a new study that forced people into the dilemma of choosing between pain and profit finds that participants cared more about other people’s well-being than their own. It is hailed as the first hard evidence of altruism for the young field of behavioral economics. Human behavior toward others is hard to predict. On the one hand, we stand out in the animal world for our altruism, often making significant sacrifices to help out a stranger in need. And all but the most antisocial people experience psychological distress at witnessing, let alone causing, pain in others. Yet study after study in the field of behavioral economics has demonstrated that we tend to value our own needs and desires above those of others. For example, researchers have found that just thinking about money makes people behave more selfishly. To try to reconcile the angels and devils of our nature, a team led by Molly Crockett, a psychologist at the University of Oxford in the United Kingdom, combined the classic psychological and economics tools for probing altruism: pain and money. Everyone has their own pain threshold, so the first task was a pain calibration. Researchers administered electric shocks with electrodes attached to the wrists of 160 subjects, starting at an almost imperceptible level and amping up until the subject described the pain as intolerable. (For most people, that threshold for pain is similar to holding your wrist under a stream of 50°C water.) © 2014 American Association for the Advancement of Science.

Related chapters from BP7e: Chapter 15: Emotions, Aggression, and Stress
Related chapters from MM:Chapter 11: Emotions, Aggression, and Stress
Link ID: 20320 - Posted: 11.18.2014

By Melissa Hogenboom Science reporter, BBC News A genetic analysis of almost 900 offenders in Finland has revealed two genes associated with violent crime. Those with the genes were 13 times more likely to have a history of repeated violent behaviour. The authors of the study, published in the journal Molecular Psychiatry, said at least 4-10% of all violent crime in Finland could be attributed to individuals with these genotypes. But they stressed the genes could not be used to screen criminals. Many more genes may be involved in violent behaviour and environmental factors are also known to have a fundamental role. Even if an individual has a "high-risk combination" of these genes the majority will never commit a crime, the lead author of the work Jari Tiihonen of the Karolinska Institutet in Sweden said. "Committing a severe, violent crime is extremely rare in the general population. So even though the relative risk would be increased, the absolute risk is very low," he told the BBC. The study, which involved analysis of almost 900 criminals, is the first to have looked at the genetic make-up of so many violent criminals in this way. Warrior gene Each criminal was given a profile based on their offences, categorising them into violent or non-violent. The association between genes and previous behaviour was strongest for the 78 who fitted the "extremely violent offender" profile. This group had committed a total of 1,154 murders, manslaughters, attempted homicides or batteries. A replication group of 114 criminals had all committed at least one murder. BBC © 2014

Related chapters from BP7e: Chapter 15: Emotions, Aggression, and Stress
Related chapters from MM:Chapter 11: Emotions, Aggression, and Stress
Link ID: 20252 - Posted: 10.28.2014

By Linda Carroll The debate over whether violent movies contribute to real-world mayhem may have just developed a wrinkle: New research suggests they might enhance aggression only in those already prone to it. Using PET scanners to peer into the brains of volunteers watching especially bloody movie scenes, researchers determined that the way a viewer’s brain circuitry responds to violent video depends upon whether the individual is aggressive by nature. The study was published Wednesday in PLOS One. “Just as beauty is in the eye of the beholder, environmental stimuli are in the brain of the beholder,” said Nelly Alia-Klein, the study’s lead author and an associate professor at the Friedman Brain Institute and the Icahn School of Medicine at Mount Sinai Hospital in New York City. To test the importance of personality, Alia-Klein and her colleagues rounded up 54 healthy men, some of whom had a history of getting into physical fights, while the others had no history of aggression. The researchers scanned the volunteers three times: doing nothing, watching emotionally charged video and viewing a violent movie. “It wasn’t the whole [violent] movie,” Alia-Klein said, “just the violent scenes, one after another after another.” Along with the brain scans, the researchers monitored blood pressure and asked about the viewers’ moods every 15 minutes.

Related chapters from BP7e: Chapter 15: Emotions, Aggression, and Stress
Related chapters from MM:Chapter 11: Emotions, Aggression, and Stress
Link ID: 20132 - Posted: 09.30.2014

By JAMES GORMAN Are chimpanzees naturally violent to one another, or has the intrusion of humans into their environment made them aggressive? A study published Wednesday in Nature is setting off a new round of debate on the issue. The study’s authors argue that a review of all known cases of when chimpanzees or bonobos in Africa killed members of their own species shows that violence is a natural part of chimpanzee behavior and not a result of actions by humans that push chimpanzee aggression to lethal attacks. The researchers say their analysis supports the idea that warlike violence in chimpanzees is a natural behavior that evolved because it could provide more resources or territory to the killers, at little risk. But critics say the data shows no such thing, largely because the measures of human impact on chimpanzees are inadequate. While the study is about chimpanzees, it is also the latest salvo in a long argument about the nature of violence in people. In studying chimpanzee violence, “we’re trying to make inferences about human evolution,” said Michael L. Wilson, an anthropologist at the University of Minnesota and a study organizer. There is no disagreement about whether chimpanzees kill one another, or about some of the claims that Dr. Wilson and his 29 co-authors make. The argument is about why chimpanzees kill. Dr. Wilson and the other authors, who contributed data on killings from groups at their study sites, say the evidence shows no connection between human impact on the chimpanzee sites and the number of killings. He said the Ngogo group of chimpanzees in Uganda “turned out to be the most violent group of chimpanzees there is,” even though the site was little disturbed by humans. They have a pristine habitat, he said, and “they go around and kill their neighbors.” © 2014 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: 20094 - Posted: 09.19.2014

By John Horgan On this blog, in my book The End of War and elsewhere (see Further Reading and Viewing), I have knocked the deep roots theory of war, which holds that war stems from an instinct deeply embedded in the genes of our male ancestors. Inter-community killings are rare among chimpanzees and non-existent among bonobos, according to a new report in Nature, undercutting the theory that the roots of war extend back to the common ancestor of humans and chimps. Proponents of this theory—notably primatologist Richard Wrangham—claim it is supported by observations of inter-community killings by chimpanzees, Pan troglodytes, our closest genetic relatives. Skeptics, including anthropologists Robert Sussman and Brian Ferguson, have pointed out that chimpanzee violence might be not an adaptation but a response to environmental circumstances, such as human encroachment. This “human impacts” hypothesis is rejected in a new report in Nature by a coalition of 30 primatologists, including Wrangham and lead author Michael Wilson. In “Lethal aggression in Pan is better explained by adaptive strategies than human impacts,” Wilson et al. analyze 152 killings in 18 chimpanzee communities and find “little correlation with human impacts.” Given that the primary interest in chimp violence is its alleged support of the deep-roots theory, it might seem odd, at first, that Wilson et al. do not mention human warfare. Actually, this omission is wise, because the Nature report undermines the deep-roots theory of war, and establishes that the “human impact” issue is a red herring. © 2014 Scientific American,

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: 20092 - Posted: 09.18.2014

by Bethany Brookshire When a laboratory mouse and a house mouse come nose to nose for the first time, each one is encountering something it has never seen before. They are both Mus musculus. But the wild mouse is facing a larger, fatter, calmer and less aggressive version of itself that’s the result of brother-to-sister inbreeding for generations, resulting in mice that are almost completely genetically identical. Laboratory mice are incredibly valuable tools for research into diseases from Alzheimer’s to Zellweger syndrome. Scientists have a deep understanding of lab mouse DNA, and can use that knowledge to study how specific genes may control certain behaviors and underlie disease. But with all the inbreeding comes some traits that, while desirable in a lab mouse, may not reflect the behavior of an animal in the wild. So for some questions, and some behaviors, scientists might need something a bit wilder. A new study takes lab mice back to their roots and along the way uncovers a new gene function. Lea Chalfin and colleagues at the Weizmann Institute of Science in Rohovot, Israel, bred laboratory mice with wild mice for 10 generations. The result was a mouse with wild mouse genes and wild mouse behavior — with a few important lab mouse genes mixed in. The technique allows scientists to place specific mutations in a wild mouse. The results have interesting implications for studying the mouse species, and might provide some new ways to study human disease as well. Chalfin and her colleagues were especially interested in behaviors linked to female aggression. © Society for Science & the Public 2000 - 2013

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: 19980 - Posted: 08.20.2014

By NATALIE ANGIER SOUTH LUANGWA NATIONAL PARK, ZAMBIA — We saw the impala first, a young buck with a proud set of ridged and twisted horns, like helical rebar, bounding across the open plain at full, desperate gallop. But why? A moment later somebody in our vehicle gasped, and the answer became clear. Rising up behind the antelope, as though conjured on movie cue from the aubergine glow of the late afternoon, were six African wild dogs, running in single file. They moved with military grace and precision, their steps synchronized, their radio-dish ears cocked forward, their long, puppet-stick legs barely skimming the ground. Still, the impala had such a jump on them that the dogs couldn’t possibly catch up — could they? We gunned the engine and followed. The pace quickened. The dogs’ discipline held steady. They were closing the gap and oh, no, did I really want to watch the kill? To my embarrassed relief, the violence was taken off-screen, when prey and predators suddenly dashed up a hill and into obscuring bushes. By the time we reached the site, the dogs were well into their communal feast, their dark muzzles glazed with bright red blood, their white-tipped tails wagging in furious joy. “They are the most enthusiastic animals,” said Rosie Woodroffe of the Institute of Zoology in London, who has studied wild dogs for the last 20 years. “Other predators may be bigger and fiercer, but I would argue that there is nothing so enthusiastic as a wild dog,” she said. “They live the life domestic dogs wish they could live.” In 1997, while devising an action plan to help save the wild dog species, Lycaon pictus, Dr. Woodroffe felt anything but exuberant. Wild dogs were considered among the most endangered of Africa’s mammals; Dr. Woodroffe had yet to see one in the wild, and she feared she never would. © 2014 The New York Times Company

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: Language and Our Divided Brain
Link ID: 19941 - Posted: 08.12.2014

From David Beckham’s infamous kick at France '98 to Luis Suárez chomping Giorgio Chiellini's shoulder in Brazil last week, the history of the World Cup is littered with moments of impulsive aggression that appear to defy all rational explanation. The story of human impulsivity stretches back deep into our evolutionary past. By nature, we are all prone to making quick, rash decisions that may lead to regret, and in some cases a four-month ban from international football. Impulsivity is actually a survival mechanism and was essential in the African savanna where our species evolved around a million and a half years ago. For our ancestors, the ability to make split-second decisions could make the difference between life and death. All of us have deep primal instincts but over the several hundred million years of evolution separating our reptilian ancestors from the first mammals, and eventually primates, the cognitive ability to exercise self-restraint has increased. While most living things make this decision purely as a trade-off between risk and reward, only humans can decide to exercise self-restraint on the basis of how they think they will be perceived by others – an ability that emerged some time in the past 100,000 years or so. “We evolved to be very social animals, living in large groups, and so we have developed inhibitory mechanisms in the more recently evolved parts of the prefrontal cortex,” explains Michael Price of the School of Social Sciences at the University of Brunel. “This is the social centre of the brain. Our big reason not to be impulsive is because of your reputation and how other people are going to judge you and perhaps ostracise you as we saw with Beckham in the aftermath of France ’98.” © 2014 Guardian News and Media Limited

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: Language and Our Divided Brain
Link ID: 19784 - Posted: 07.03.2014

By Jonathan Webb Science reporter, BBC News A new theory suggests that our male ancestors evolved beefy facial features as a defence against fist fights. The bones most commonly broken in human punch-ups also gained the most strength in early "hominin" evolution. They are also the bones that show most divergence between males and females. The paper, in the journal Biological Reviews, argues that the reinforcements evolved amid fighting over females and resources, suggesting that violence drove key evolutionary changes. For many years, this extra strength was seen as an adaptation to a tough diet including nuts, seeds and grasses. But more recent findings, examining the wear pattern and carbon isotopes in australopith teeth, have cast some doubt on this "feeding hypothesis". "In fact, [the australopith] boisei, the 'nutcracker man', was probably eating fruit," said Prof David Carrier, the new theory's lead author and an evolutionary biologist at the University of Utah. Masculine armour Instead of diet, Prof Carrier and his co-author, physician Dr Michael Morgan, propose that violent competition demanded the development of these facial fortifications: what they call the "protective buttressing hypothesis". In support of their proposal, Carrier and Morgan offer data from modern humans fighting. Several studies from hospital emergency wards, including one from the Bristol Royal Infirmary, show that faces are particularly vulnerable to violent injuries. BBC © 2014

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: 19710 - Posted: 06.09.2014

Bullying casts a long shadow. Children who are bullied are more prone to depression and suicidal tendencies even when they grow up; they're also more likely to get sick and have headaches and stomach troubles, researchers have discovered. A new study may have found the underlying cause: A specific indicator of illness, called C-reactive protein (CRP), is higher than normal in bullying victims, even when they get older. In contrast, the bullies, by the same gauge, seem to be healthier. The researchers focused on CRP because it's a common, easily tested marker of inflammation, the runaway immune system activity that's a feature of many chronic illnesses including cardiovascular disease, diabetes, chronic pain, and depression, explains lead author William Copeland, a psychologist and epidemiologist at Duke University Medical Center in Durham, North Carolina. To link inflammation to bullying, the researchers asked 1420 youngsters between the ages of 9 and 16 whether, and how often, they had been bullied or had bullied others. Interviewers asked participants whether they felt more teased, bullied, or treated meanly by siblings, friends, and peers than other children—and whether they had upset or hurt other people on purpose, tried to get others in trouble, or forced people to do something by threatening or hurting them. The researchers took finger stick blood tests at each assessment. Interviews took place once a year until the participants turned 16, and again when they were 19 and 21. The children interviewed were participants in the larger Great Smoky Mountains Study, in which some 12,000 children in North Carolina were assessed to track the development of psychiatric conditions. In the short term, the effect of bullying on the victims was immediate. CRP levels increased along with the number of reported bullying instances, and more than doubled in those who said they'd been bullied three times or more in the previous year, compared with kids who had never been bullied. No change was seen in bullies, or in kids who hadn't been involved with bullying one way or the other, the researchers report online today in the Proceedings of the National Academy of Sciences. © 2014 American Association for the Advancement of Science.

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: 19610 - Posted: 05.13.2014

by Colin Barras PICTURE the scene: a weak leader is struggling to hold onto power as ambitious upstarts plot to take over. As tensions rise, the community splits and the killing begins. The war will last for years. No, this isn't the storyline of an HBO fantasy drama, but real events involving chimps in Tanzania's Gombe Stream National Park. A look at the social fragmentation that led to a four-year war in the 1970s now reveals similarities between the ways chimpanzee and human societies break down. Jane Goodall has been studying the chimpanzees of Gombe for over 50 years. During the early 1970s the group appeared to split in two, and friendliness was replaced by fighting. So extreme and sustained was the aggression that Goodall dubbed it a war. Joseph Feldblum at Duke University in Durham, North Carolina, and colleagues have re-examined Goodall's field notes from the chimp feeding station she established at Gombe to work out what led to the conflict. In the past, researchers have estimated the strength of social ties based on the amount of time two chimps spent together at the station. But the notes are so detailed that Feldblum could get a better idea of each chimp's social ties, for instance, by considering if the chimps arrived at the same time and from the same direction. His team then plugged this data into software that can describe the chimps' social network. They did this for several periods between 1968 and 1972, revealing when the nature of the network changed. © 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: 19591 - Posted: 05.10.2014

By JAMES GORMAN Males’ aggression toward each other is an old story throughout the animal kingdom. It’s not that females aren’t aggressive, but in many species, male-on-male battles are more common. Take fruit flies. “The males are more aggressive than females,” said David J. Anderson, a California Institute of Technology neuroscientist who knows their tussles well. Dr. Anderson runs a kind of fight club for fruit flies in his lab at Caltech, with the goal of understanding the deep evolutionary roots of very fundamental behaviors. Dr. Anderson, Kenta Asahina and a group of their colleagues recently identified one gene and a tiny group of neurons, sometimes as few as three, present only in the brains of male fruit flies, that can control aggression. The gene is also found in mammals, and has also been associated with aggression in some mammalian species, perhaps even in humans, although that is not clear. The discovery, reported in the journal Cell last month, does not tell the whole story of fly aggression. Some fighting is inextricably linked to food and mating, while the mechanism the scientists found is not. But it is a striking indication of how brain structure and chemistry work together, as well as a reminder that as different as humans and flies are, they are not always very far apart. The painstaking process of discovery, recounted step by step in the paper, gives a glimpse of modern brain research and the lengths to which scientists must go if they want to get down to the level of how neurons control behavior. “They did a huge amount of experiments,” said Ulrike Heberlein at the Janelia Farm research campus of the Howard Hughes Medical Institute. Dr. Heberlein also studies fly behavior and recently demonstrated another human-fly connection, showing that jilted male flies will turn to drink. © 2014 The New York Times Company

Related chapters from BP7e: Chapter 15: Emotions, Aggression, and Stress
Related chapters from MM:Chapter 11: Emotions, Aggression, and Stress
Link ID: 19203 - Posted: 02.04.2014

|By Meredith Knight When most of us imagine someone in pain, we feel uncomfortable and want to help. Psychopaths do not: a callousness toward others' suffering is the central feature of a psychopathic personality. Now an imaging study finds that psychopathic inmates have deficits in a key empathy circuit in the brain, pointing to a potential therapeutic target. Jean Decety, a psychologist at the University of Chicago, and his colleagues used functional MRI to scan the brains of 121 male prison inmates while they looked at photos of a painful moment, such as a foot stepping on a nail or a finger being smashed in a drawer. The inmates were instructed to imagine the scenario happening to themselves or to another person, a perspective-switching technique that easily elicits empathy in most people. Inmates who scored the highest on a standard psychopathy test showed a normal response in pain perception and brain centers for emotion when imagining the pain for themselves. Yet when asked to imagine the scenario happening to others, their brains did not show typical connectivity between the amygdala, an area important for fear and emotional processing, and the ventromedial prefrontal cortex, a region vital for emotion regulation, empathy and morality. Some results even indicated that pleasure regions might have become active instead. The brain areas that are undercommunicating in psychopathy “are key for experiencing empathetic concern and caring for one another, which is what empathy is all about and what individuals who score high on psychopathy do not have,” Decety says. © 2014 Scientific American

Related chapters from BP7e: Chapter 15: Emotions, Aggression, and Stress
Related chapters from MM:Chapter 11: Emotions, Aggression, and Stress
Link ID: 19162 - Posted: 01.25.2014

Tim Phillips, GlobalPost As we begin 2014, we still haven’t engaged in a conversation about gun control that brings both sides together. Polls indicate a country more or less divided over how to prevent another school shooting. And while legislation has been proposed to reign in the gun lobby, sales of guns have soared. This debate is not a new one in the United States, and while it intensifies with each tragic mass shooting, the conversation rarely advances. Frustration sets in as each new action causes the other side to dig in their heels even further. We wonder: Is there another way to frame this issue? For the last 20 years I have led an international organization that works in war torn countries to negotiate an end to conflict. In places like Northern Ireland, El Salvador, South Africa and the Balkans, groups once driven to violence to defend their beliefs have put down their weapons, sat down at a table, overcome their differences and negotiated. Moving beyond conflict is, indeed, possible. One dynamic I have observed present in all successful negotiations — which is missing from our current debate over gun control — is a recognition of the role of sacred values. Social scientists define sacred values as a set of values or principles that individuals and communities hold dear to their idea of right and wrong, that define who they are and help guide their daily lives. We first came to see the critical role played by sacred values in the 1990s in dealing with the bloody conflict in Northern Ireland in which thousands of people were killed. No one used the term sacred values back then, but we could see clearly that one of the reasons negotiations to end sectarian conflict between Catholics and Protestants in Ireland were failing was because they were not recognizing or respecting the deep differences in values, cultures and identities that each side held. © 2014 Salon Media Group, Inc.

Related chapters from BP7e: Chapter 15: Emotions, Aggression, and Stress
Related chapters from MM:Chapter 11: Emotions, Aggression, and Stress
Link ID: 19119 - Posted: 01.11.2014

By MICHAEL LUO and MIKE McINTIRE Last April, workers at Middlesex Hospital in Connecticut called the police to report that a psychiatric patient named Mark Russo had threatened to shoot his mother if officers tried to take the 18 rifles and shotguns he kept at her house. Mr. Russo, who was off his medication for paranoid schizophrenia, also talked about the recent elementary school massacre in Newtown and told a nurse that he “could take a chair and kill you or bash your head in between the eyes,” court records show. The police seized the firearms, as well as seven high-capacity magazines, but Mr. Russo, 55, was eventually allowed to return to the trailer in Middletown where he lives alone. In an interview there recently, he denied that he had schizophrenia but said he was taking his medication now — though only “the smallest dose,” because he is forced to. His hospitalization, he explained, stemmed from a misunderstanding: Seeking a message from God on whether to dissociate himself from his family, he had stabbed a basketball and waited for it to reinflate itself. When it did, he told relatives they would not be seeing him again, prompting them to call the police. As for his guns, Mr. Russo is scheduled to get them back in the spring, as mandated by Connecticut law. “I don’t think they ever should have been taken out of my house,” he said. “I plan to get all my guns and ammo and knives back in April.” The Russo case highlights a central, unresolved issue in the debate over balancing public safety and the Second Amendment right to bear arms: just how powerless law enforcement can be when it comes to keeping firearms out of the hands of people who are mentally ill. Connecticut’s law giving the police broad leeway to seize and hold guns for up to a year is actually relatively strict. Most states simply adhere to the federal standard, banning gun possession only after someone is involuntarily committed to a psychiatric facility or designated as mentally ill or incompetent after a court proceeding or other formal legal process. Relatively few with mental health issues, even serious ones, reach this point. © 2013 The New York Times Company

Related chapters from BP7e: Chapter 15: Emotions, Aggression, and Stress; Chapter 16: Psychopathology: Biological Basis of Behavior Disorders
Related chapters from MM:Chapter 11: Emotions, Aggression, and Stress; Chapter 12: Psychopathology: Biological Basis of Behavioral Disorders
Link ID: 19064 - Posted: 12.23.2013

By Greg Miller John McCluskey killed a vacationing couple in eastern New Mexico in 2010, set their camper trailer on fire with their bodies inside, and took off with their truck. In sentencing hearings held after his conviction, McCluskey’s lawyers argued that he should be spared the death penalty because abnormalities in his brain had made him impulsive and unable to control his behavior. Last week, a jury declared it had been unable to reach the unanimous decision required to sentence him to death. It’s not known if the brain scans and other scientific evidence played a role in McCluskey escaping the death penalty. And it’s not the first time such evidence has been introduced when the death penalty was on the line. In fact, neuroscience is making increasingly regular courtroom appearances. “It’s amazing the extent to which judges, attorneys, and juries are taking this in stride,” said Owen Jones, a legal scholar at Vanderbilt University who observed a few hours of testimony in McCluskey’s case. “Just a few generations ago, this was beyond the realm of science fiction,” Jones said. But now, “you watch the jurors and they reflect no outward manifestation of what an extraordinary thing it is to look inside another person’s brain.” ‘It’s amazing the extent to which judges, attorneys, and juries are taking this in stride.’ Nita Farahany, a bioethicist at Duke University has been tracking the rise of legal cases involving neuroscience evidence in the U.S. The number of judicial opinions mentioning neuroscience evidence tripled between 2005 and 2011, from roughly 100 to more than 300. “It’s more prevalent than my numbers show,” Farahany said. That’s because most cases involving neuroscience evidence do not result in a written judicial opinion, and those that don’t are exceedingly difficult to find. © 2013 Condé Nast.

Related chapters from BP7e: Chapter 15: Emotions, Aggression, and Stress; Chapter 18: Attention and Higher Cognition
Related chapters from MM:Chapter 11: Emotions, Aggression, and Stress; Chapter 14: Attention and Consciousness
Link ID: 19045 - Posted: 12.17.2013

by Chelsea Whyte For chameleons, war paint isn't just an accessory, it is a battle flag. The brightness of the colours these lizards display and how rapidly they change are good indicators of which animal will win in a fight. Chameleons are famous for changing colour to hide from predators by blending into their surroundings, but they also use colour for social communication. One of the most diversely coloured species is the veiled chameleon (Chamaeleo calyptratus), which lives in parts of Saudi Arabia and Yemen. "At their brightest, they have vertical yellow stripes, blue-green bellies, black speckles that provide contrast and make their stripes stand out, and orange around the corner of their mouths," says Russell Ligon, a behavioural ecologist at Arizona State University in Tempe. To see if individual variations in these colours and patterns influenced the outcome of a fight, Ligon and his colleague Kevin McGraw staged a round-robin tournament in which 10 male veiled chameleons were pitted against each other. Using a high-speed camera, they were able to capture the brightness and colour changes from 28 points on each animal, taking into account how the colours would look to a chameleon's eye – which sees both visible and ultraviolet light. They found that males with the brightest side stripes were more likely to instigate a fight, whereas those with brighter heads that changed colour most rapidly were more likely to win. This suggests that different colours and patterns may signal different aspects of competitive behaviour – how motivated the chameleon is versus its strength. © 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: 19023 - Posted: 12.11.2013

By JAMES GORMAN Sometimes the scientists who study animal behavior solve puzzles and other times they uncover new ones. The war between mockingbirds and cowbirds is a case in point. Cowbirds are brood parasites, meaning they lay their eggs in the nests of other bird species, thus unloading the messy and demanding business of chick-rearing. They also peck holes in the eggs of the host birds, destroying as many as they can. Mockingbirds are a favorite target of this plan, and it seems to make perfect sense for them to viciously attack cowbirds when they catch them in the nest. But when Ros Gloag, then a doctoral student at Oxford, and her colleagues in Argentina looked closely at the war between chalk-browed mockingbirds and shiny cowbirds, they found something unexpected, as they reported in the November issue of Animal Behaviour. They stationed small video cameras near the nests of 40 pairs of chalk-browed mockingbirds. Over two breeding seasons they recorded more than 200 attacks on intruding cowbirds. They were surprised to find that these attacks, which their videos show to be quite vicious, did not stop the cowbirds from laying eggs. The cowbirds would hunker down and let the much large mockingbirds deliver hammer blows to the head, but in matter of seconds they would lay an egg and flee. How could such a failed strategy persist in evolution? © 2013 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: 19014 - Posted: 12.10.2013

Philip Ball Some animals, like some people, are more aggressive than others: it is just the way they are. But research suggests that for birds at least, it is not always easy to tell which is which. Some birds are inclined to give out exaggerated signs of their aggressiveness, others to underplay it. It is rather like the menacing biker who turns out to be a pussycat, or the geek who will break a bottle over your head. But the analogy with humans goes only so far, because many birds announce their aggression about mating and territory not by appearance but through song and gesture. For example, behavioural ecologist Michael Beecher and his colleagues at the University of Washington in Seattle have observed how the song sparrow (Melospiza melodia) indicates its intention to attack a dummy bird (see video above) or a loudspeaker playing bird songs by either vocalizing distinctive ‘soft songs’ or waving its wings (see video below), both of which are perceived as threatening1. Violent tendencies Both aggressive signalling and the ensuing violent behaviour vary from one bird to another, in a way that correlates with other personality traits such as boldness2. But these attributes also vary for a single individual at different times: birds can have particularly grouchy or placid days. Nonetheless, the degree of aggression implied by the precursory signals generally reflects the actual behaviour, in what evolutionary biologists call an honest signal. But it's not always honest. Earlier this year, Beecher's team showed1 that there is some variability in aggressive signalling that does not match behaviour: a bird might act stroppy but not follow through with an attack. © 2013 Nature Publishing Group

Related chapters from BP7e: Chapter 15: Emotions, Aggression, and Stress
Related chapters from MM:Chapter 11: Emotions, Aggression, and Stress
Link ID: 19002 - Posted: 12.05.2013

One afternoon in October 2005, neuroscientist James Fallon was looking at brain scans of serial killers. As part of a research project at UC Irvine, he was sifting through thousands of PET scans to find anatomical patterns in the brain that correlated with psychopathic tendencies in the real world. “I was looking at many scans, scans of murderers mixed in with schizophrenics, depressives and other, normal brains,” he says. “Out of serendipity, I was also doing a study on Alzheimer’s and as part of that, had brain scans from me and everyone in my family right on my desk.” “I got to the bottom of the stack, and saw this scan that was obviously pathological,” he says, noting that it showed low activity in certain areas of the frontal and temporal lobes linked to empathy, morality and self-control. Knowing that it belonged to a member of his family, Fallon checked his lab’s PET machine for an error (it was working perfectly fine) and then decided he simply had to break the blinding that prevented him from knowing whose brain was pictured. When he looked up the code, he was greeted by an unsettling revelation: the psychopathic brain pictured in the scan was his own. Many of us would hide this discovery and never tell a soul, out of fear or embarrassment of being labeled a psychopath. Perhaps because boldness and disinhibition are noted psychopathic tendencies, Fallon has gone all in towards the opposite direction, telling the world about his finding in a TED Talk, an NPR interview and now a new book published last month, The Psychopath Inside. In it, Fallon seeks to reconcile how he—a happily married family man—could demonstrate the same anatomical patterns that marked the minds of serial killers. “I’ve never killed anybody, or raped anyone,” he says. “So the first thing I thought was that maybe my hypothesis was wrong, and that these brain areas are not reflective of psychopathy or murderous behavior.”

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: 18964 - Posted: 11.25.2013