Chapter 15. Brain Asymmetry, Spatial Cognition, and Language

Follow us on Facebook and Twitter, or subscribe to our mailing list, to receive news updates. Learn more.


Links 41 - 60 of 2290

By CLAY ROUTLEDGE Are Americans becoming less religious? It depends on what you mean by “religious.” Polls certainly indicate a decline in religious affiliation, practice and belief. Just a couple of decades ago, about 95 percent of Americans reported belonging to a religious group. This number is now around 75 percent. And far fewer are actively religious: The percentage of regular churchgoers may be as low as 15 to 20 percent. As for religious belief, the Pew Research Center found that from 2007 to 2014 the percentage of Americans who reported being absolutely confident God exists dropped from 71 percent to 63 percent. Nonetheless, there is reason to doubt the death of religion, or at least the death of what you might call the “religious mind” — our concern with existential questions and our search for meaning. A growing body of research suggests that the evidence for a decline in traditional religious belief, identity and practice does not reflect a decline in this underlying spiritual inclination. Ask yourself: Why are people religious to begin with? One view is that religion is an ancient way of understanding and organizing the world that persists largely because societies pass it down from generation to generation. This view is related to the idea that the rise of science entails the fall of religion. It also assumes that the strength of religion is best measured by how much doctrine people accept and how observant they are. This view, however, does not capture the fundamental nature of the religious mind — our awareness of, and need to reckon with, the transience and fragility of our existence, and how small and unimportant we seem to be in the grand scheme of things. In short: our quest for significance. © 2017 The New York Times Company

Keyword: Attention; Emotions
Link ID: 23868 - Posted: 07.24.2017

Jon Hamilton Professional fighter Gina Mazany practices during a training session at Xtreme Couture Mixed Martial Arts in Las Vegas. She well remembers her first concussion — which came in her first fight. "I was throwing up that night, Mazany says. Bridget Bennett for NPR Gina Mazany grew up in Anchorage, Alaska. And that's where she had her first fight. "It was right after I turned 18," she recalls. A local bar had a boxing ring, and Mazany decided to give it a shot. Her opponent was an older woman with a "mom haircut." "She beat the crap out of me," Mazany says. "Like she didn't knock me out, she didn't finish me. But she just knocked me around for three rounds. And I remember, later that night I was very, very nauseous. I was throwing up that night." It was her first concussion. Concussions are just part of her sport, Mazany figures, but says she tries to protect herself, and to not give anyone else a head injury--at least in training. Bridget Bennett for NPR Thanks to research on boxers and football players, both athletes and the public are becoming more aware of the dangers of sports-related head injuries. Yet there is little data on participants like Mazany. That's because, unlike the vast majority of athletes studied, she is a woman. "We classically have always known the male response to brain injury," says Mark Burns, at Georgetown University. But there have been remarkably few studies of females. The bias runs throughout the scientific literature, even in studies of mice. © 2017 npr

Keyword: Brain Injury/Concussion
Link ID: 23865 - Posted: 07.24.2017

By Ryan Cross Whether caused by a car accident that slams your head into the dashboard or repeated blows to your cranium from high-contact sports, traumatic brain injury can be permanent. There are no drugs to reverse the cognitive decline and memory loss, and any surgical interventions must be carried out within hours to be effective, according to the current medical wisdom. But a compound previously used to enhance memory in mice may offer hope: Rodents who took it up to a month after a concussion had memory capabilities similar to those that had never been injured. The study “offers a glimmer of hope for our traumatic brain injury patients,” says Cesario Borlongan, a neuroscientist who studies brain aging and repair at the University of South Florida in Tampa. Borlongan, who reviewed the new paper, notes that its findings are especially important in the clinic, where most rehabilitation focuses on improving motor—not cognitive—function. Traumatic brain injuries, which cause cell death and inflammation in the brain, affect 2 million Americans each year. But the condition is difficult to study, in part because every fall, concussion, or blow to the head is different. Some result in bleeding and swelling, which must be treated immediately by drilling into the skull to relieve pressure. But under the microscope, even less severe cases appear to trigger an “integrated stress response,” which throws protein synthesis in neurons out of whack and may make long-term memory formation difficult. © 2017 American Association for the Advancement of Science.

Keyword: Learning & Memory; Brain Injury/Concussion
Link ID: 23825 - Posted: 07.11.2017

Nicola Davis People who drink coffee have a lower risk of dying from a host of causes, including heart disease, stroke and liver disease, research suggests – but experts say it’s unclear whether the health boost is down to the brew itself. The connection, revealed in two large studies, was found to hold regardless of whether the coffee was caffeinated or not, with the effect higher among those who drank more cups of coffee a day. But scientists say that the link might just be down to coffee-drinkers having healthier behaviours. “It is plausible that there is something else behind this that is causing this relationship,” said Marc Gunter, a co-author of one of the studies, from the International Agency for Research on Cancer. But, he added, based on the consistency of the results he would be surprised if coffee itself didn’t play a role in reducing the risk of death. About 2.25bn cups of coffee are consumed worldwide every day. While previous studies have suggested coffee might have health benefits, the latest research involves large and diverse cohorts of participants. The first study looked at coffee consumption among more than 185,000 white and non-white participants, recruited in the early 1990s and followed up for an average of over 16 years. The results revealed that drinking one cup of coffee a day was linked to a 12% lower risk of death at any age, from any cause while those drinking two or three cups a day had an 18% lower risk, with the association not linked to ethnicity. © 2017 Guardian News and Media Limited

Keyword: Drug Abuse; Stroke
Link ID: 23823 - Posted: 07.11.2017

By Linda Geddes BILLIONS of dollars have been spent in search of treatments for psychiatric conditions and brain disorders, when a cheap and effective drug may have been right under our noses: light. Now hospitals are turning to light to treat depression, strokes and Parkinson’s disease, using it to hit the reset button on our internal clocks. From green light soothing the pain of migraine, to blue light reducing organ damage during surgery, recent small studies have uncovered some intriguing effects of this therapy. But apart from easing seasonal affective disorder, we’ve been slow to embrace light as a serious contender for treating neurological conditions. We’ve known for 15 years that a special kind of receptor in our eyes transmits information directly to the body’s master clock, as well as other brain areas that control mood and alertness. These cells are particularly responsive to bluish light, including sunlight. These receptors enable light to act as a powerful reset switch, keeping the clock in our brain synced to the outside world. But this clock can fall out of sync or weaken as part of ageing or a range of disorders – a problem doctors are now starting to treat with light. Most hospitals have small windows and 24-hour lighting, both of which might exacerbate health problems. To tackle this, several hospitals in Europe and the US are installing dynamic “solid state” lighting, which changes like daylight over the course of a day. Such lights can, for example, shine bright whitish-blue in the morning, grow warmer and dimmer throughout the day, and turn orange or switch off at night. © Copyright New Scientist Ltd.

Keyword: Biological Rhythms; Stroke
Link ID: 23808 - Posted: 07.06.2017

By Sandrine Ceurstemont Bird or beast? A cuckoo seems to have learned how to mimic the sounds made by the pig-like peccaries it lives alongside, perhaps to ward off predators. The Neomorphus ground cuckoos live in forests in Central and South America, where they often follow herds of wild peccaries so they can feed on the invertebrates that the peccaries disturb as they plough through the leaf litter. Ecologists have noticed that when the cuckoos clap their beaks together they sound a lot like the tooth clacks the peccaries make to deter large predatory cats. To find out whether this is just coincidence or evidence of mimicry, Cibele Biondo at the Federal University of ABC in Brazil and her team analysed the cuckoo and peccary sounds, and compared them with the beak clapping sounds made by roadrunners – close relatives of the ground cuckoos. Logically, the cuckoos should sound most similar to roadrunners, given that the two are closely related. But the analysis suggested otherwise. “The acoustic characteristics are more similar to the teeth clacking of peccaries,” says Biondo. She suspects that cuckoos have something to gain by imitating the peccaries, particularly in the dark, dense forests where predators rely on hearing as much as vision. “Cuckoos may deceive predators by making it appear that peccaries are present when they are not,” says Biondo. © Copyright New Scientist Ltd.

Keyword: Evolution; Animal Communication
Link ID: 23802 - Posted: 07.04.2017

By Dina Fine Maron Not all of Mitchell Elkind’s stroke patients are on social security. In recent years he has treated devastating attacks in people as young as 18. And he is not alone. A growing body of research indicates strokes among U.S. millennials—ages 18 to 34—have soared in recent years. But an analysis by Scientific American has revealed significant differences in where these strokes are occurring, depending both on region and whether people live in rural or urban settings. The investigation, which used data from the U.S. Department of Health and Human Services’ Agency for Healthcare Research and Quality (AHRQ), was reviewed by five stroke experts and found that the West and Midwest have seen especially worrisome increases among younger adults. Moreover, large cities appear to have seen bigger increases than rural areas. The analysis employed hospital discharge data from 2003 to 2012 from the AHRQ’s Healthcare Cost and Utilization Project (HCUP) database. The findings align with earlier studies that pointed to nationwide increases in strokes in this age group: In a study published earlier this year in JAMA Neurology, researchers at the U.S. Centers for Disease Control and Prevention concluded that in a nine-year span from 2003 to 2012 there was a 32 percent spike in strokes among 18- to 34-year-old women and a 15 percent increase for men in the same range. Scientific American’s analysis sought to dig deeper into the data by exploring whether the stroke trend differed by location. © 2017 Scientific American

Keyword: Stroke
Link ID: 23788 - Posted: 06.29.2017

Kerin Higa After surgery to treat her epilepsy severed the connection between the two halves of her brain, Karen's left hand took on a mind of its own, acting against her will to undress or even to slap her. Amazing, to be sure. But what may be even more amazing is that most people who have split-brain surgery don't notice anything different at all. But there's more to the story than that. In the 1960s, a young neuroscientist named Michael Gazzaniga began a series of experiments with split-brain patients that would change our understanding of the human brain forever. Working in the lab of Roger Sperry, who later won a Nobel Prize for his work, Gazzaniga discovered that the two halves of the brain experience the world quite differently. When Gazzaniga and his colleagues flashed a picture in front of a patient's right eye, the information was processed in the left side of the brain and the split-brain patient could easily describe the scene verbally. But when a picture was flashed in front of the left eye, which connects to the right side of the brain, the patient would report seeing nothing. If allowed to respond nonverbally, however, the right brain could adeptly point at or draw what was seen by the left eye. So the right brain knew what it was seeing; it just couldn't talk about it. These experiments showed for the first time that each brain hemisphere has specialized tasks. In this third episode of Invisibilia, hosts Alix Spiegel and Hanna Rosin talk to several people who are trying to change their other self, including a man who confronts his own biases and a woman who has a rare condition that causes one of her hands to take on a personality of its own. © 2017 npr

Keyword: Consciousness; Laterality
Link ID: 23749 - Posted: 06.17.2017

By JANE E. BRODY Hurray for the HotBlack Coffee cafe in Toronto for declining to offer Wi-Fi to its customers. There are other such cafes, to be sure, including seven of the eight New York City locations of Café Grumpy. But it’s HotBlack’s reason for the electronic blackout that is cause for hosannas. As its president, Jimson Bienenstock, explained, his aim is to get customers to talk with one another instead of being buried in their portable devices. “It’s about creating a social vibe,” he told a New York Times reporter. “We’re a vehicle for human interaction, otherwise it’s just a commodity.” What a novel idea! Perhaps Mr. Bienenstock instinctively knows what medical science has been increasingly demonstrating for decades: Social interaction is a critically important contributor to good health and longevity. Personally, I don’t need research-based evidence to appreciate the value of making and maintaining social connections. I experience it daily during my morning walk with up to three women, then before and after my swim in the locker room of the YMCA where the use of electronic devices is not allowed. The locker room experience has been surprisingly rewarding. I’ve made many new friends with whom I can share both joys and sorrows. The women help me solve problems big and small, providing a sounding board, advice and counsel and often a hearty laugh that brightens my day. © 2017 The New York Times Company

Keyword: Stress
Link ID: 23730 - Posted: 06.12.2017

By Amina Zafar, CBC News Senator Murray Sinclair suffered a mild stroke 10 years ago, while he was still serving as a justice in Manitoba. He got swift treatment, but says for weeks after even simple tasks left him exhausted. It's a hidden issue many stroke survivors experience, according to a new report. A stroke happens in about one in 10,000 adults under the age of 64, the group says. Sinclair, who experienced his stroke in 2007 at the age of 56, recalls waking up feeling dizzy and fuzzy headed. He had trouble getting into his robes for court and found he was bumping into a desk and doorway. Typing with his left hand was also difficult. Sinclair chalked it up to lack of sleep. After court, he called his family doctor in Winnipeg. The doctor performed a few co-ordination tests, immediately administered Aspirin and sent him to the emergency department where he was diagnosed, treated and released that night with medication and follow-up appointments arranged. "For several weeks thereafter whenever I would do something, if I would just go for a walk or if I would go outside and try to cut the grass, which I couldn't, I would just be too exhausted to finish a task. Or after I'd done a small task I'd just need to lay down or sit down," he recalled in an interview. "Even writing and reading were problematic for a while." ©2017 CBC/Radio-Canada.

Keyword: Stroke
Link ID: 23715 - Posted: 06.07.2017

Giuseppe Gangarossa Could it be possible to run a normal existence without social life? Indeed, sociability is an important aspect for individuals and social interaction builds our lives. In fact, social interaction enhances quality of life and improves the stability of communities. Impaired sociability is a classical symptom observed in many neuropsychiatric disorders including autism, schizophrenia, depression, anxiety and generalized fear. Interestingly, many studies have pointed to the medial prefrontal cortex (mPFC), a brain area located in the ventromedial part of the frontal lobe, as key region involved in the neural bases of sociability (Valk et al, 2015; Treadway et al., 2015; Frith et al., 2007). The prelimbic cortex (PL) and the infralimbic cortex (IL), two subregions of the mPFC, have been strongly suggested to play an important role in the neural mechanisms underlying sociability as isolation rearing in rats results in impaired social behavior and structural modifications in the PL and IL. Isolation rearing is a neurodevelopmental manipulation that produces neurochemical, structural, and behavioral alterations in rodents that in many ways are consistent with psychiatric disorders such as schizophrenia, anxiety and depression. In particular, it has been shown that isolation rearing can alter the volume of mPFC, the dendritic length and the spine density of pyramidal neurons. However, the detailed mechanisms involved in sociability disorders remain elusive and poorly understood. A recent article published in Plos ONE by Minami and colleagues aimed at measuring neural activity in the PL and IL of control and isolated rats during social interaction in order to determine whether there is neural activity related to social behavior in these areas.

Keyword: Attention
Link ID: 23688 - Posted: 06.01.2017

By LAWRENCE K. ALTMAN, M.D. Evidence continues to mount that professional athletes in a number of contact sports are suffering brain damage as a result of head impacts. But there is no reliable test to detect the injury, called chronic traumatic encephalopathy, in its earliest stages. Even if a doctor strongly suspects that an athlete’s confusion or memory loss is related to C.T.E., proof can only be obtained on autopsy. Now a small study of National Football League players suggests another possibility: that the signs of C.T.E. may be found with a low-cost, noninvasive test that tracks changes in conversational language years before symptoms appear. If it works, the linguistic test also would be valuable in assessing the effectiveness of treatments to prevent cognitive damage because of C.T.E. or to slow its progression. In the study, to be published this week in the journal Brain and Language, researchers at Arizona State University tracked a steeper decline in vocabulary size and other verbal skills in 10 players who spoke at news conferences over an eight-year period, compared with 18 coaches and executives who had never played professional football and who also spoke in news conferences during the same period. The players included seven quarterbacks, one nose tackle, one cornerback and one wide receiver. Although the small sample size and limited study period prevented reaching definitive conclusions, the findings underscored the need for larger, long-term studies of changes in spoken and written language that could be harbingers of severe brain damage later in life. And not just for injuries related to C.T.E. Development of a reliable linguistic tool could also help evaluate head injuries among military personnel and victims of domestic violence, said Dr. Javier Cardenas, who directs the Concussion and Brain Injury Center at the Barrow Neurological Institute in Phoenix. © 2017 The New York Times Company

Keyword: Brain Injury/Concussion; Language
Link ID: 23679 - Posted: 05.30.2017

By Julie Hecht I have been scaring dog lovers for nearly a decade, and Tamas Farago—lead researcher behind a new study on dog growls and cross-species communication—is mostly to blame. I met Farago in 2010 when visiting his research group—the Family Dog Project at Eotvos Lorand University—to conduct my Masters research. By then, Farago was already immersed in the study of dog vocalizations—particularly their barks and growls—so when my study concluded and it was time to leave Budapest, I departed with not only a deep appreciation for paprika and palinka, but also a few audio clips of dogs growling, courtesy of Farago. Since then, whenever I give a talk about canine science, audience members are sure to chuckle, their faces brightening, as recordings of a dog’s breathy, garbled, fast-paced, play growls take over the room. But when I play the low, elongated aggressive growls corresponding to a dog being approached by a threatening stranger or a dog guarding food, even my hair will often stand up. These growls mean business. If a dog happens to be attending the talk—not that I hold lectures for dogs, but if a human brought their dog—I take note before playing the growls. This is because a 2010 study by Farago and colleagues found that dogs not only listen to growls, but extract meaningful information from them. Here’s how they figured this out: In the study, dogs entered a room where they came across a bone. Fine. Normal so far. Just a bone sitting all alone. But unbeknownst to the dogs, a speaker was concealed in a covered crate sitting just behind the bone, and as the dogs approached, one of three growls was played from the speaker (food guarding, threatening stranger, or play). Excellent work sneaky researchers! © 2017 Scientific American

Keyword: Animal Communication; Language
Link ID: 23672 - Posted: 05.29.2017

By Virginia Morell Baby marmosets learn to make their calls by trying to repeat their parents’ vocalizations, scientists report today in Current Biology. Humans were thought to be the only primate with vocal learning—the ability to hear a sound and repeat it, considered essential for speech. When our infants babble, they make apparently random sounds, which adults respond to with words or other sounds; the more this happens, the faster the baby learns to talk. To find out whether marmosets (Callithrix jacchus, pictured) do something similar, scientists played recordings of parental calls during a daily 30-minute session to three sets of newborn marmoset twins until they were 2 months old (roughly equivalent to a 2-year-old human). Baby marmosets make noisy guttural cries; adults respond with soft “phee” contact calls (listen to their calls below). The baby that consistently heard its parents respond to its cries learned to make the adult “phee” sound much faster than did its twin, the team found. It’s not yet known if this ability is limited to the marmosets; if so, the difference may be due to the highly social lives of these animals, where, like us, multiple relatives help care for babies. © 2017 American Association for the Advancement of Science

Keyword: Language; Animal Communication
Link ID: 23662 - Posted: 05.26.2017

Gary Stix Illiterate women in northern Indian learned how to read and write in Hindi for six months after which they had reached a level comparable to a first-grader. Credit: Max Planck Institute for Human Cognitive and Brain Sciences The brain did not evolve to read. It uses the neural muscle of pre-existing visual and language processing areas to enable us to take in works by Tolstoy and Tom Clancy. Reading, of course, begins in the first years of schooling, a time when these brain regions are still in development. What happens, though, when an adult starts learning after the age of 30? A study published May 24 in Science Advances turned up a few unexpected findings. In the report, a broad-ranging group of researchers—from universities in Germany, India and the Netherlands—taught reading to 21 women, all about 30 years of age from near the city of Lucknow in northern India, comparing them to a placebo group of nine women. The majority of those who learned to read could not recognize a word of Hindi at the beginning of the study. After six months, the group had reached a first-grade proficiency level. When the researchers conducted brain scans—using functional magnetic resonance imaging—they were startled. Areas deep below the wrinkled surface, the cortex, in the brains of the new learners had changed. Their results surprised them because most reading-related brain activity was thought to involve the cortex. The new research may overturn this presumption and may pertain pertain to child learners as well. After being filtered through the eyes, visual information may move first to evolutionarily ancient brain regions before being relayed to the visual and language areas of the cortex typically associated with reading. © 2017 Scientific American

Keyword: Language
Link ID: 23661 - Posted: 05.25.2017

By Bret Stetka For many hours a day they pluck dirt, debris and bugs from each other’s fur. Between grooming sessions they travel in troops to search for food. When ignored by mom, they throw tantrums; when not ignored by zoo-goers, they throw feces. Through these behaviors, monkeys demonstrate they understand the meaning of social interactions with other monkeys. They recognize when their peers are grooming one another and infer social rank from seeing such actions within their group. But it has long been unclear how the brains of our close evolutionary relatives actually process what they observe of these social situations. New findings published Thursday in Science offer a clue. A team of researchers from The Rockefeller University have identified a network in the monkey brain dedicated exclusively to analyzing social interactions. And they believe this network could be akin to human brains’ social circuitry. In the new work—led by Winrich Freiwald, an associate professor of neurosciences and behavior—four rhesus macaques viewed videos of various social and physical interactions while undergoing functional magnetic resonance imaging. (Monkeys love watching TV, so they paid attention.) They were shown clips of monkeys interacting, as well as performing tasks on their own. They also watched videos of various physical interactions among inanimate objects. © 2017 Scientific American

Keyword: Attention; Evolution
Link ID: 23637 - Posted: 05.19.2017

By GRETCHEN REYNOLDS When young athletes sustain concussions, they are typically told to rest until all symptoms disappear. That means no physical activity, reading, screen time, or friends, and little light exposure, for multiple days and, in severe cases, weeks. Restricting all forms of activity after a concussion is known as “cocooning.” But now new guidelines, written by an international panel of concussion experts and published this month in the British Journal of Sports Medicine, question that practice. Instead of cocooning, the new guidelines suggest that most young athletes should be encouraged to start being physically active with a day or two after the injury. “The brain benefits from movement and exercise, including after a concussion,” says Dr. John Leddy, a professor of orthopedics at the Jacobs School of Medicine and Biomedical Sciences at the University at Buffalo, and one of the co-authors of the new guidelines. There has long been controversy, of course, about the best ways to identify and treat sports-related concussions. Twenty years ago, athletes who banged their heads during play were allowed to remain in the practice or game, even if they stumbled, seemed disoriented, or were “seeing stars.” Little was known then about any possible immediate or long-term consequences from head trauma during sports or about the best responses on the sidelines and afterward. Since then, mounting evidence has indicated that sports-related concussions are not benign and require appropriate treatment. The question has been what these appropriate treatments should be. In the early 2000s, dozens of the world’s premier experts on sports-related concussions started meeting to review studies about concussions, with plans to issue a consensus set of guidelines on how best to identify and deal with the condition. © 2017 The New York Times Company

Keyword: Brain Injury/Concussion
Link ID: 23633 - Posted: 05.18.2017

By DAVE PHILIPPS Three-fifths of troops discharged from the military for misconduct in recent years had a diagnosis of post-traumatic stress disorder, traumatic brain injury or another associated condition, according to a report released Tuesday by the Government Accountability Office. The report, mandated by Congress, for the first time combined military medical and staffing data, as well as data from the Department of Veterans Affairs, to show that tens of thousands of wounded troops were kicked out of the armed forces and severed from benefits designed to ease their transition from service in war. “It is everything many of us believed for years” said Kristopher Goldsmith, a veteran who served in Iraq and was discharged for misconduct after a suicide attempt. He is now an assistant director for policy at Vietnam Veterans of America, a veterans advocacy group based in Washington. “Many people didn’t believe that the problem could be this big. Now I hope Congress will direct the resources to making it right.” From 2011 to 2015, according to the report, nearly 92,000 troops were discharged for misconduct — the military equivalent of being fired. Troops can be discharged for reasons like testing positive for drugs or repeatedly showing up late. And in recent years, as the military was downsized, misconduct discharges surged. Of those discharged, 57,000 had a diagnosis of PTSD, traumatic brain injury (known as T.B.I.) or a related condition. About 9,000 were found to have PTSD or T.B.I. But a majority had a personality disorder or an adjustment disorder — diagnoses that count as pre-existing conditions, not war wounds. Critics of the military’s handling of mental health have long accused the military of using such diagnoses to sidestep safeguards put in place for troops with PTSD. © 2017 The New York Times Company

Keyword: Brain Injury/Concussion; Stress
Link ID: 23626 - Posted: 05.17.2017

Nicola Davis Humans can determine a dog’s mood by the sound of its growl, scientists have found, with women showing greater ability than men. While previous studies have found that humans can unpick the context of barks, the latest study investigated whether the same was true of canine grumbles, with some previous research suggesting humans struggle to differentiate between playful and aggressive vocalisations. “It is an important thing that humans are capable [of recognising] the emotional state of another species just based on the vocal characteristics,” said Tamás Faragó, first author of the study from Eötvös Loránd University in Hungary. To tackle the conundrum, Faragó and colleagues used previously captured recordings of 18 dogs growling in three contexts: guarding food from other dogs, playing tug-of-war with humans, and being threatened by the approach of a stranger. The researchers monitored several features, including the length of each growl and its frequency. Two sets of the recordings, which included two growls from each context, were played to 40 adults. Each participant was asked to record their impression of the first set of growls on a sliding scale, rating their perception of the dog for five emotions: fear, aggression, despair, happiness and playfulness. © 2017 Guardian News and Media Limited

Keyword: Animal Communication; Sexual Behavior
Link ID: 23621 - Posted: 05.17.2017

By FERRIS JABR Con Slobodchikoff and I approached the mountain meadow slowly, obliquely, softening our footfalls and conversing in whispers. It didn’t make much difference. Once we were within 50 feet of the clearing’s edge, the alarm sounded: short, shrill notes in rapid sequence, like rounds of sonic bullets. We had just trespassed on a prairie-dog colony. A North American analogue to Africa’s meerkat, the prairie dog is trepidation incarnate. It lives in subterranean societies of neighboring burrows, surfacing to forage during the day and rarely venturing more than a few hundred feet from the center of town. The moment it detects a hawk, coyote, human or any other threat, it cries out to alert the cohort and takes appropriate evasive action. A prairie dog’s voice has about as much acoustic appeal as a chew toy. French explorers called the rodents petits chiens because they thought they sounded like incessantly yippy versions of their pets back home. On this searing summer morning, Slobodchikoff had taken us to a tract of well-trodden wilderness on the grounds of the Museum of Northern Arizona in Flagstaff. Distressed squeaks flew from the grass, but the vegetation itself remained still; most of the prairie dogs had retreated underground. We continued along a dirt path bisecting the meadow, startling a prairie dog that was peering out of a burrow to our immediate right. It chirped at us a few times, then stared silently. “Hello,” Slobodchikoff said, stooping a bit. A stout bald man with a scraggly white beard and wine-dark lips, Slobodchikoff speaks with a gentler and more lilting voice than you might expect. “Hi, guy. What do you think? Are we worth calling about? Hmm?” Slobodchikoff, an emeritus professor of biology at Northern Arizona University, has been analyzing the sounds of prairie dogs for more than 30 years. Not long after he started, he learned that prairie dogs had distinct alarm calls for different predators. Around the same time, separate researchers found that a few other species had similar vocabularies of danger. What Slobodchikoff claimed to discover in the following decades, however, was extraordinary: Beyond identifying the type of predator, prairie-dog calls also specified its size, shape, color and speed; the animals could even combine the structural elements of their calls in novel ways to describe something they had never seen before. No scientist had ever put forward such a thorough guide to the native tongue of a wild species or discovered one so intricate. Prairie-dog communication is so complex, Slobodchikoff says — so expressive and rich in information — that it constitutes nothing less than language.

Keyword: Language; Evolution
Link ID: 23606 - Posted: 05.12.2017