Chapter 19. Language and Lateralization

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By Pam Belluck He has not been able to speak since 2003, when he was paralyzed at age 20 by a severe stroke after a terrible car crash. Now, in a scientific milestone, researchers have tapped into the speech areas of his brain — allowing him to produce comprehensible words and sentences simply by trying to say them. When the man, known by his nickname, Pancho, tries to speak, electrodes implanted in his brain transmit signals to a computer that displays his intended words on the screen. His first recognizable sentence, researchers said, was, “My family is outside.” The achievement, published on Wednesday in the New England Journal of Medicine, could eventually help many patients with conditions that steal their ability to talk. “This is farther than we’ve ever imagined we could go,” said Melanie Fried-Oken, a professor of neurology and pediatrics at Oregon Health & Science University, who was not involved in the project. Three years ago, when Pancho, now 38, agreed to work with neuroscience researchers, they were unsure if his brain had even retained the mechanisms for speech. “That part of his brain might have been dormant, and we just didn’t know if it would ever really wake up in order for him to speak again,” said Dr. Edward Chang, chairman of neurological surgery at University of California, San Francisco, who led the research. The team implanted a rectangular sheet of 128 electrodes, designed to detect signals from speech-related sensory and motor processes linked to the mouth, lips, jaw, tongue and larynx. In 50 sessions over 81 weeks, they connected the implant to a computer by a cable attached to a port in Pancho’s head, and asked him to try to say words from a list of 50 common ones he helped suggest, including “hungry,” “music” and “computer.” As he did, electrodes transmitted signals through a form of artificial intelligence that tried to recognize the intended words. © 2021 The New York Times Company

Keyword: Brain imaging; Language
Link ID: 27913 - Posted: 07.17.2021

By Melissa J. Coleman, Eric Fortune A fundamental feature of vocal communication is taking turns: when one person says something, the other person listens and then responds. Turn-taking requires precise coordination of the timing of signals between individuals. We have all found over the past year communicating over Zoom that disruptions of the timing of auditory cues—like those annoying delays caused by poor connections—make effective communication difficult and frustrating. How do the brains of two individuals synchronize their activity patterns for rapid turn-taking during vocal communication? We addressed this question in a recently published paper by studying turn-taking in a specialist, the plain-tailed wren (Pheugopedius euophrys), which sings precisely timed duets. Our findings demonstrate the ability to coordinate relies on sensory cues from one partner that temporarily inhibit vocalizations in the other. These birds sing duets in which females and males alternate their vocalizations, called syllables, so rapidly it sounds as if a single bird is singing. These wrens live in dense bamboo on the slopes of the Andes. To study the neural basis of duet singing, we flew to Ecuador where we loaded up a truck with equipment and drove to a remote field-site called the Yanayacu Biological Field Station and Center for Creative Studies. Much of our equipment required electricity, so we had to bring car batteries for backup and used a six-meter copper rod that we drove into the soft mountain earth for our electrical ground. Our “lab bench” was a door that we placed on two Pelican suitcases. First, we had to catch pairs of wrens, so we hacked through bamboo with machetes and set up mist nets. We then attracted pairs to the nets by playing the duets of wrens. To see how neurons responded during duets, we surgically implanted very small wires into a specific region of the brain, called HVC. Neurons in this region are responsible for producing the song—that is, they are premotor—and they also respond to auditory signals. To transmit the neural signals (i.e., action potentials) to a computer, a small wireless digital transmitter was then connected to the wires. We then had to wait for the birds to sing their remarkable duets. © 2021 Scientific American,

Keyword: Animal Communication; Language
Link ID: 27908 - Posted: 07.14.2021

Andrew Anthony David Eagleman, 50, is an American neuroscientist, bestselling author and presenter of the BBC series The Brain, as well as co-founder and chief executive officer of Neosensory, which develops devices for sensory substitution. His area of speciality is brain plasticity, and that is the subject of his new book, Livewired, which examines how experience refashions the brain, and shows that it is a much more adaptable organ than previously thought. For the past half-century or more the brain has been spoken of in terms of a computer. What are the biggest flaws with that particular model? It’s a very seductive comparison. But in fact, what we’re looking at is three pounds of material in our skulls that is essentially a very alien kind of material to us. It doesn’t write down memories, the way we think of a computer doing it. And it is capable of figuring out its own culture and identity and making leaps into the unknown. I’m here in Silicon Valley. Everything we talk about is hardware and software. But what’s happening in the brain is what I call livewire, where you have 86bn neurons, each with 10,000 connections, and they are constantly reconfiguring every second of your life. Even by the time you get to the end of this paragraph, you’ll be a slightly different person than you were at the beginning. In what way does the working of the brain resemble drug dealers in Albuquerque? It’s that the brain can accomplish remarkable things without any top-down control. If a child has half their brain removed in surgery, the functions of the brain will rewire themselves on to the remaining real estate. And so I use this example of drug dealers to point out that if suddenly in Albuquerque, where I happened to grow up, there was a terrific earthquake, and half the territory was lost, the drug dealers would rearrange themselves to control the remaining territory. It’s because each one has competition with his neighbours and they fight over whatever territory exists, as opposed to a top-down council meeting where the territory is distributed. And that’s really the way to understand the brain. It’s made up of billions of neurons, each of which is competing for its own territory. © 2021 Guardian News & Media Limited

Keyword: Development of the Brain; Stroke
Link ID: 27855 - Posted: 06.16.2021

Vincent Acovino A young, red-handed tamarin monkey. Some of these monkeys are changing their vocal call to better communicate with another species of tamarin. Schellhorn/ullstein bild/Getty Images In the Brazilian Amazon, a species of monkey called the pied tamarin is fighting for survival, threatened by habitat loss and urban development. But the critically endangered primate faces another foe: the red-handed tamarin, a more resilient monkey that lives in the same region. They compete for the same resources, and the red-handed tamarin's habitat range is expanding into that of the pied tamarins'. Their clashes sometimes end in violent altercations. But in a recent study, scientists have discovered that the red-handed tamarin is altering its vocal calls to better communicate with the pied tamarin. Tainara Sobroza, an ecology Ph.D. student who worked on the study, says these "territorial calls" are used to warn other species that they are encroaching on their territory, or coming too close to a crucial survival resource. "When this happens, [the two species] usually engage in vocal battles," she says, which sometimes prevent the violent physical battles between the two species. Researchers likened the change in calls to speaking with an accent. "They might need to say 'tomahto' instead of 'tomayto' — that's the kind of nuance in the accent, so that they can really understand each other," Jacob Dunn, a professor of evolutionary biology who worked on the study, told The Guardian. Article continues after sponsor message When analyzing the vocal call of both species, the scientists discovered that the red-handed tamarins new call has a narrower bandwidth and an increased amplitude, making the sound clearer and the duration of the call longer. The result is a call that travels better through the dense forest. © 2021 npr

Keyword: Animal Communication; Language
Link ID: 27842 - Posted: 06.02.2021

By Sofia Moutinho Neotropical river otters spend most of their time alone, but that doesn’t stop them from being big chatterboxes. These animals—which live in Central and South America—make a variety of squeaks and growls to convey everything from surprise to playfulness, a new study has found. The discovery could help reveal how communication evolved in all otters—and perhaps help protect these endangered animals. “The study is an in-depth and insightful investigation into the vocal repertoire of this understudied otter species,” says Alexander Saliveros, a biologist and otter expert at the University of Exeter who was not part of the research. All otters make sounds like growls and squeaks to communicate. Some social species, such as the Amazon’s giant otter (Pteronura brasiliensis), use up to 22 different call types. Others, like the lonesome North American river otter (Lontra canadensis), only have four known calls. But the neotropical river otter (L. longicaudis) has largely remained a mystery. Solitary inhabitants of rivers and lakes, they come together only once a year to mate. That makes their communication especially hard to study, says Sabrina Bettoni, a bioacoustician at the University of Vienna. So Bettoni observed three pairs of playful neotropical river otters—orphans living in a shelter on the island of Santa Catarina, off the southern coast of Brazil. The animals were kept in female-male couples year-round at the Institute Ekko Brazil, a nonprofit focused on wildlife protection. Bettoni recorded every vocalization the animals made. Then, she and colleagues analyzed the sound waves to make sure they were distinct calls with unique properties. Bettoni also spent 3 months observing the animals to understand what calls they used in which situations. © 2021 American Association for the Advancement of Science.

Keyword: Animal Communication; Language
Link ID: 27829 - Posted: 05.27.2021

Ian Sample Science editor A man who was paralysed from the neck down in an accident more than a decade ago has written sentences using a computer system that turns imagined handwriting into words. It is the first time scientists have created sentences from brain activity linked to handwriting and paves the way for more sophisticated devices to help paralysed people communicate faster and more clearly. The man, known as T5, who is in his 60s and lost practically all movement below his neck after a spinal cord injury in 2007, was able to write 18 words a minute when connected to the system. On individual letters, his “mindwriting” was more than 94% accurate. Frank Willett, a research scientist on the project at Stanford University in California, said the approach opened the door to decoding other imagined actions, such as 10-finger touch typing and attempted speech for patients who had permanently lost their voices. “Instead of detecting letters, the algorithm would be detecting syllables, or rather phonemes, the fundamental unit of speech,” he said. Amy Orsborn, an expert in neural engineering at the University of Washington in Seattle, who was not involved in the work, called it “a remarkable advance” in the field. Scientists have developed numerous software packages and devices to help paralysed people communicate, ranging from speech recognition programs to the muscle-driven cursor system created for the late Cambridge cosmologist Stephen Hawking, who used a screen on which a cursor automatically moved over the letters of the alphabet. To select one, and to build up words, he simply tensed his cheek. © 2021 Guardian News & Media Limited

Keyword: Brain imaging; Robotics
Link ID: 27822 - Posted: 05.15.2021

By Virginia Morell Like members of a street gang, male dolphins summon their buddies when it comes time to raid and pillage—or, in their case, to capture and defend females in heat. A new study reveals they do this by learning the “names,” or signature whistles, of their closest allies—sometimes more than a dozen animals—and remembering who consistently cooperated with them in the past. The findings indicate dolphins have a concept of team membership—previously seen only in humans—and may help reveal how they maintain such intricate and tight-knit societies. “It is a ground-breaking study,” says Luke Rendell, a behavioral ecologist at the University of St. Andrews who was not involved with the research. The work adds evidence to the idea that dolphins evolved large brains to navigate their complex social environments. Male dolphins typically cooperate as a pair or trio, in what researchers call a “first-order alliance.” These small groups work together to find and corral a fertile female. Males also cooperate in second-order alliances comprised of as many as 14 dolphins; these defend against rival groups attempting to steal the female. Some second-order alliances join together in even larger third-order alliances, providing males in these groups with even better chances of having allies nearby should rivals attack. © 2021 American Association for the Advancement of Science

Keyword: Animal Communication; Language
Link ID: 27785 - Posted: 04.24.2021

By Nikk Ogasa Honey bees can’t speak, of course, but scientists have found that the insects combine teamwork and odor chemicals to relay the queen’s location to the rest of the colony, revealing an extraordinary means of long distance, mass communication. The research is “really nice, and really careful,” says Gordon Berman, a biologist at Emory University who was not involved in the study. It shows once again, he says, that insects are capable of “exquisite and complex behaviors.” Honey bees communicate with chemicals called pheromones, which they sense through their antennae. Like a monarch pressing a button, the queen emits pheromones to summon worker bees to fulfill her needs. But her pheromones only travel so far. Busy worker bees, however, roam around, and they, too, can call to each other by releasing a pheromone called Nasanov, through a gesticulation known as “scenting; they raise their abdomens to expose their pheromone glands and fan their wings to direct the smelly chemicals backward (seen in the video above, and close-up in the video below). Scientists have long known individual bees scented, but just how these individual signals work together to gather tens of thousands of bees around a queen, such as when the colony leaves the hive to swarm, has remained a mystery. © 2021 American Association for the Advancement of Science.

Keyword: Animal Communication; Evolution
Link ID: 27767 - Posted: 04.10.2021

By Jake Buehler Watch a group of lions yawn, and it may seem like nothing more than big, lazy cats acting sleepy, but new research suggests that these yawns may be subtly communicating some important social cues. Yawning is not only contagious among lions, but it appears to help the predators synchronize their movements, researchers report March 16 in Animal Behaviour. The discovery was partially made by chance, says Elisabetta Palagi, an ethologist at the University of Pisa in Italy. While studying play behavior in spotted hyenas in South Africa, she and colleagues often had the opportunity to watch lions (Panthera leo) at the same time. And she quickly noticed that lions yawn quite frequently, concentrating these yawns in short time periods. Yawning is ubiquitous among vertebrates, possibly boosting blood flow to the skull, cooling the brain and aiding alertness, especially when transitioning in and out of rest (SN: 9/8/15). Fish and reptiles will yawn, but more social vertebrates such as birds and mammals appear to have co-opted the behavior for purposes conducive to group living. In many species — like humans, monkeys, and even parakeets (SN: 6/1/15) — yawners can infect onlookers with their “yawn contagion,” leading onlookers to yawn shortly afterwards. Seeing the lions yawn reminded Palagi of her own work on contagious yawning in primates. Curious if the lions’ prodigious yawning was socially linked, Palagi and her team started recording videos of the big cats, analyzing when they were yawning and any behaviors around those times. © Society for Science & the Public 2000–2021

Keyword: Animal Communication; Stress
Link ID: 27759 - Posted: 04.08.2021

By Jake Buehler A light crackling sound floats above a field in northern Switzerland in late summer. Its source is invisible, tucked inside a dead, dried plant stem: a dozen larval mason bees striking the inner walls of their herbaceous nest. While adult bees and wasps make plenty of buzzy noises, their young have generally been considered silent. But the babies of at least one bee species make themselves heard, playing percussion instruments growing out of their faces and rear ends, researchers report February 25 in the Journal of Hymenoptera Research. The larvae’s chorus of tapping and rasping may be a clever strategy to befuddle predatory wasps. Unlike honeybees, the mason bee (Hoplitis tridentata) lives a solitary life. Females chew into dead plant stems and lay their eggs inside, often in a single row of chambers lined up along its length. After hatching, the larvae feed on a provision of pollen left by the mom, spin a cocoon and overwinter as a pupa inside the stem. Andreas Müller, an entomologist at the nature conservation research agency Natur Umwelt Wissen GmbH in Zurich, has been studying bees in the Osmiini tribe, which includes mason bees and their close relatives, for about 20 years. Noticing that H. tridentata populations have been declining in northern Switzerland, he and colleague Martin Obrist tried to help the bees. “We offered the bees bundles of dry plant stems as nesting sites, and when we checked the bundles we heard the larval sounds for the first time,” says Müller. “This is a new phenomenon not only in the osmiine bees, but in bees in general.” He and Obrist, a biologist at the Swiss Federal Institute for Forest, Snow and Landscape Research in Birmensdorf, gathered stem nests from the field and subjected them to various types of physical disturbance, trying to determine what kinds of pestering triggers the bee larvae to drum. In some nests, the duo cut windows into the stems to observe larvae through the translucent cocoon walls, unveiling the secret of how the insects were creating the noises. © Society for Science & the Public 2000–2021.

Keyword: Animal Communication; Language
Link ID: 27737 - Posted: 03.17.2021

By Christa Lesté-Lasserre If you’ve ever counted to three before jumping into the pool with a friend, you’ve got something in common with dolphins. The sleek marine mammals use coordinated clicks and whistles to tell each other the precise moment to perform a backflip or push a button, according to new research. That makes them the only animals besides humans known to cooperate with vocal cues. The new work is “fascinating,” says Richard Connor, a cetacean biologist at the University of Massachusetts, Dartmouth, who was not involved with the research. “We just see so much cooperation and synchrony [among dolphins] in the wild. This helps us understand how they accomplish that.” Free-roaming dolphins are often in sync. They hunt in large groups and drive away rivals with coordinated displays. They can even match others’ movements down to their breathing patterns. But how do they achieve such synchronicity? Scientists have long suspected the cetaceans coordinate their actions through vocal cues. Underwater microphones, called hydrophones, have been picking up their whistles and clicks for decades. But dolphins don’t open their mouths when they “talk,” and tracking underwater sound has long been a technical challenge. So scientists have been developing ways to capture those sounds. In France, researchers recently combined five hydrophones to set up a star-shaped pattern that can pinpoint which dolphin in a group is “speaking,” says ethologist Juliana Lopez-Marulanda of Paris-Saclay University who co-developed the approach. © 2021 American Association for the Advancement of Science.

Keyword: Animal Communication; Language
Link ID: 27736 - Posted: 03.17.2021

By Rachel Nuwer The ability to link language to the world around us is a crowning feature of our species. For very young infants, it is not yet about learning the meaning of words like “cat” or “dog.” Rather, the acoustic signals in speech help foster infants' fundamental cognitive capacities, including the formation of categories of objects, such as cats or dogs. The sounds that activate this key step in development can come not just from human language but also from vocalizations made by nonhuman primates. A new study shows that babies do not use just any natural sound to build cognition, however. While primate calls and human language pass the test, birdsongs do not. “By tracing the link from language to cognition and how it’s built up with babies’ experiences with objects in the world, we get to see what are the components of this quintessential human ability to go beyond the here and now,” says Sandra Waxman, a developmental scientist at Northwestern University and senior author of the findings, which were published today in PLOS ONE. “Asking how broad that earliest link is helps to answer questions about our evolutionary legacy.” By three or four months of age, infants can categorize objects—from toys and food to pets and people—based on commonalities those objects share. This ability is boosted if the objects are presented while the infants are listening to language. The new findings build on previous work Waxman and her colleagues conducted about which sounds outside of the realm of human speech support infants’ ability to categorize objects. In past studies, they found that sequences of pure tones and backward speech do not help infants under six months of age to categorize objects, whereas listening to vocalizations from nonhuman primates—specifically, lemurs—does..” © 2021 Scientific American,

Keyword: Development of the Brain; Language
Link ID: 27731 - Posted: 03.13.2021

By Linda Searing People who smoke even occasionally are more likely than nonsmokers to have a serious type of stroke caused by a ruptured blood vessel — 27 percent more likely if they smoke up to 20 packs a year, according to research published in the journal Stroke. The average American smoker, according to the Centers for Disease Control and Prevention, smokes 14 cigarettes daily, which means about 255 packs a year. The type of stroke examined by the researchers, known as a subarachnoid hemorrhage, occurs when a weakened blood vessel ruptures and bleeds into the space between a person’s brain and skull. Most often, this results from an aneurysm, an abnormal bulge in a blood vessel. A subarachnoid hemorrhage is not as common as an ischemic stroke, which is caused by a blood clot, but it also can lead to neurological problems or be life-threatening without immediate treatment to stop the bleeding. To focus on the effect that smoking may have on people’s risk for this type of stroke, the researchers analyzed data on 408,609 adults, about a third of whom smoked regularly. During the study period, 904 participants had a subarachnoid hemorrhage. The more people smoked, the greater their risk for this type of stroke, prompting the American Stroke Association to note that the findings “provide evidence for a causal link” between smoking and subarachnoid hemorrhage. washingtonpost.com © 1996-2021

Keyword: Drug Abuse; Stroke
Link ID: 27707 - Posted: 02.28.2021

By Alex Vadukul In the early 1970s, the field of neuroradiology was still in its formative years, and among its early practitioners was Dr. John Bentson, at UCLA Medical Center in Los Angeles. As he helped patients with the aid of new technology like the CT scan and computer imaging, he saw an opportunity for innovation. A subspecialty of radiology, neuroradiology involves diagnosing and treating ailments in the brain, spinal cord and nerves. One tool used in treatment is the combination of an angiographic guidewire and catheter, essentially a slender wire and tube. Inserted through the leg, it can aid with the injection of contrast dye for diagnostic brain imaging and the treatment of aneurysms. At the time, however, guidewires were rigid and at worst could injure a blood vessel. Dr. Bentson decided to design a better type. He conceived of a more supple guidewire that also featured a flexible tip, and after UCLA built an early prototype for him, other neuroradiologists started using his model. Cook Medical began manufacturing the device in 1973, and it’s still in use today, commonly known as a Bentson guidewire. Dr. Bentson died at 83 on Dec. 28 at a hospital in Los Angeles. The cause was complications of Covid-19, his daughter Dr. Erika Drazan said. “He liked to push boundaries if he thought he could help the patient,” she said. “He liked saying that the vessels in the body are just like a tree, and that he could get where he wanted through them by feel.” Thousands of patients have benefited from his innovation, The American Society of Neuroradiology said after his death. John Reinert Bentson was born on May 15, 1937, in Viroqua, Wis., to Carl and Stella (Hagen) Bentson, who were of Norwegian heritage. He was raised on his family’s dairy farm, going to school in the winter on wooden skis. His mother prepared Norwegian fare like lutefisk. © 2021 The New York Times Company

Keyword: Brain imaging; Stroke
Link ID: 27689 - Posted: 02.15.2021

By Carolyn Gramling The fin whale’s call is among the loudest in the ocean: It can even penetrate into Earth’s crust, a new study finds. Echoes in whale songs recorded by seismic instruments on the ocean floor reveal that the sound waves pass through layers of sediment and underlying rock. These songs can help probe the structure of the crust when more conventional survey methods are not available, researchers report in the Feb. 12 Science. Six songs, all from a single whale that sang as it swam, were analyzed by seismologists Václav Kuna of the Czech Academy of Sciences in Prague and John Nábělek of Oregon State University in Corvallis. They recorded the songs, lasting from 2.5 to 4.9 hours, in 2012 and 2013 with a network of 54 ocean-bottom seismometers in the northeast Pacific Ocean. The songs of fin whales (Balaenoptera physalus) can be up to 189 decibels, as noisy as a large ship. Seismic instruments detect the sound waves of the song, just like they pick up pulses from earthquakes or from air guns used for ship-based surveys. The underwater sounds can also produce seismic echoes: When sound waves traveling through the water meet the ground, some of the waves’ energy converts into a seismic wave (SN: 9/17/20). Those seismic waves can help scientists “see” underground: As the penetrating waves bounce off different rock layers, researchers can estimate the thickness of the layers. Changes in the waves’ speed can also reveal what types of rocks the waves traveled through. © Society for Science & the Public 2000–2021.

Keyword: Hearing; Animal Communication
Link ID: 27686 - Posted: 02.13.2021

By Gina Kolata Is it possible to predict who will develop Alzheimer’s disease simply by looking at writing patterns years before there are symptoms? According to a new study by IBM researchers, the answer is yes. And, they and others say that Alzheimer’s is just the beginning. People with a wide variety of neurological illnesses have distinctive language patterns that, investigators suspect, may serve as early warning signs of their diseases. For the Alzheimer’s study, the researchers looked at a group of 80 men and women in their 80s — half had Alzheimer’s and the others did not. But, seven and a half years earlier, all had been cognitively normal. The men and women were participants in the Framingham Heart Study, a long-running federal research effort that requires regular physical and cognitive tests. As part of it, they took a writing test before any of them had developed Alzheimer’s that asks subjects to describe a drawing of a boy standing on an unsteady stool and reaching for a cookie jar on a high shelf while a woman, her back to him, is oblivious to an overflowing sink. The researchers examined the subjects’ word usage with an artificial intelligence program that looked for subtle differences in language. It identified one group of subjects who were more repetitive in their word usage at that earlier time when all of them were cognitively normal. These subjects also made errors, such as spelling words wrongly or inappropriately capitalizing them, and they used telegraphic language, meaning language that has a simple grammatical structure and is missing subjects and words like “the,” “is” and “are.” The members of that group turned out to be the people who developed Alzheimer’s disease. The A.I. program predicted, with 75 percent accuracy, who would get Alzheimer’s disease, according to results published recently in The Lancet journal EClinicalMedicine. © 2021 The New York Times Company

Keyword: Alzheimers; Language
Link ID: 27677 - Posted: 02.03.2021

By Jonathan Lambert When one naked mole-rat encounters another, the accent of their chirps might reveal whether they’re friends or foes. These social rodents are famous for their wrinkly, hairless appearance. But hang around one of their colonies for a while, and you’ll notice something else — they’re a chatty bunch. Their underground burrows resound with near-constant chirps, grunts, squeaks and squeals. Now, computer algorithms have uncovered a hidden order within this cacophony, researchers report in the Jan. 29 Science. These distinctive chirps, which pups learn when they’re young, help the mostly blind, xenophobic rodents discern who belongs, strengthening the bonds that maintain cohesion in these highly cooperative groups. “Language is really important for extreme social behavior, in humans, dolphins, elephants or birds,” says Thomas Park, a biologist at the University of Illinois Chicago who wasn’t involved in the study. This work shows naked mole-rats (Heterocephalus glaber) belong in those ranks as well, Park says. Naked mole-rat groups seem more like ant or termite colonies than mammalian societies. Every colony has a single breeding queen who suppresses the reproduction of tens to hundreds of nonbreeding worker rats that dig elaborate subterranean tunnels in search of tubers in eastern Africa (SN: 10/18/04). Food is scarce, and the rodents vigorously attack intruders from other colonies. While researchers have long noted the rat’s raucous chatter, few actually studied it. “Naked mole-rats are incredibly cooperative and incredibly vocal, and no one has really looked into how these two features influence one another,” says Alison Barker, a neuroscientist at the Max Delbrück Center for Molecular Medicine in Berlin. © Society for Science & the Public 2000–2021.

Keyword: Language; Evolution
Link ID: 27673 - Posted: 01.30.2021

Bob McDonald Scientists used raw eggs to simulate the damaging effects on the brain from strikes to the head, with surprising results. If someone calls you an egghead, they are not too far off. Think about it: an egg has a hard outer shell; a liquid interior, which is the white of the egg; and liquid yolk surrounded by a membrane suspended in the centre. Your head also has a hard outer skull and liquid, called the cerebrospinal fluid, inside of it — which, among other things, acts as a shock absorber around the squishy brain. In a research paper in the journal Physics of Fluids, scientists from Villanova University in Pennsylvania conducted rather simple kitchen style experiments on raw eggs to simulate strikes to the head that could lead to concussion. They wanted to determine how much shock absorbing protection the egg white would provide the yolk and how much the yolk would be distorted out of shape during an impact. The results were not what they expected. Applying force to monitor yolk deformation In order to see the yolks in action, the egg material was placed in a clear plastic container that was mounted on springs and filmed with high speed cameras. First, they hit it in a straight line by dropping a 1.77 kg weight on it from a height of one metre. representing a direct blow to the head. To their surprise, the yolk remained suspended in the egg white and did not change shape or break as the container suddenly accelerated downwards. This could be because liquids cannot be compressed, and since the two liquids are almost the same density, both of them moved together as one unit. ©2021 CBC/Radio-Canada.

Keyword: Brain Injury/Concussion
Link ID: 27658 - Posted: 01.23.2021

Researchers from the National Institutes of Health have discovered Jekyll and Hyde immune cells in the brain that ultimately help with brain repair but early after injury can lead to fatal swelling, suggesting that timing may be critical when administering treatment. These dual-purpose cells, which are called myelomonocytic cells and which are carried to the brain by the blood, are just one type of brain immune cell that NIH researchers tracked, watching in real-time as the brain repaired itself after injury. The study, published in Nature Neuroscience, was supported by the National Institute of Neurological Disorders and Stroke (NINDS) Intramural Research Program at NIH. “Fixing the brain after injury is a highly orchestrated, coordinated process, and giving a treatment at the wrong time could end up doing more harm than good,” said Dorian McGavern, Ph.D., NINDS scientist and senior author of the study. Cerebrovascular injury, or damage to brain blood vessels, can occur following several conditions including traumatic brain injury or stroke. Dr. McGavern, along with Larry Latour, M.D., NINDS scientist, and their colleagues, observed that a subset of stroke patients developed bleeding and swelling in the brain after surgical removal of the blood vessel clot responsible for the stroke. The swelling, also known as edema, results in poor outcomes and can even be fatal as brain structures become compressed and further damaged. To understand how vessel injury can lead to swelling and to identify potential treatment strategies, Dr. McGavern and his team developed an animal model of cerebrovascular injury and used state-of-the-art microscopic imaging to watch how the brain responded to the damage in real-time.

Keyword: Brain Injury/Concussion
Link ID: 27653 - Posted: 01.20.2021

By Elizabeth Pennisi Hammer a nail into a tree, and it will get stuck. So why doesn’t the same thing happen to the sharp beaks of woodpeckers? Scientists say they finally have the answer. In a new study, researchers took high-speed videos of two black woodpeckers (Dryocopus martius) pecking away at hardwood trunks in zoos and analyzed them frame by frame to see how the head and beak moved throughout each peck. The bird’s secret: an ability to move its upper and lower beaks independently, the team reports this week at the virtual annual meeting of the Society for Integrative and Comparative Biology. Once the tip of the woodpecker’s bill hits the wood, the bird’s head rotates to the side ever so slightly, lifting the top part of the beak and twisting it a bit in the other direction, the videos reveal. This pull opens the bill a tiny amount and creates free space between the beak tip and the wood at the bottom of the punctured hole, so the bird can then easily retract its beak. Until now, scientists have thought woodpecker bills would need to be rigidly attached to the skull to successfully drill into the wood to find insect prey. But actually, the bill’s flexibility in these joints ensures that the bird’s signature “rat-a-tat-tat” doesn’t stop at “rat.” © 2021 American Association for the Advancement of Science.

Keyword: Brain Injury/Concussion; Evolution
Link ID: 27640 - Posted: 01.09.2021