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 1 - 20 of 2502

By Knvul Sheikh Shortly after the birth of her first son, Monika Jones learned that he had a rare neurological condition that made one side of his brain abnormally large. Her son, Henry, endured hundreds of seizures a day. Despite receiving high doses of medication, his little body seemed like a rag doll as one episode blended into another. He required several surgeries, starting when he was 3 1/2 months old, eventually leading to a complete anatomical hemispherectomy, or the removal of half of his brain, when he turned 3. The procedure was first developed in the 1920s to treat malignant brain tumors. But its success in children who have brain malformations, intractable seizures or diseases where damage is confined to half the brain, has astonished even seasoned scientists. After the procedure, many of the children are able to walk, talk, read and do everyday tasks. Roughly 20 percent of patients who have the procedure go on to find gainful employment as adults. Now, research published Tuesday in the journal Cell Reports suggests that some individuals recover so well from the surgery because of a reorganization in the remaining half of the brain. Scientists identified the variety of networks that pick up the slack for the removed tissue, with some of the brain’s specialists learning to operate like generalists. “The brain is remarkably plastic,” said Dorit Kliemann, a cognitive neuroscientist at the California Institute of Technology, and the first author of the study. “It can compensate for dramatic loss of brain structure, and in some cases the remaining networks can support almost typical cognition.” The study was partially funded by a nonprofit organization that Mrs. Jones and her husband set up to advocate for others who need surgery to stop seizures. The study’s findings could provide encouragement for those seeking hemispherectomies beyond early childhood. © 2019 The New York Times Company

Keyword: Development of the Brain; Laterality
Link ID: 26837 - Posted: 11.20.2019

By Robert Martone We humans have evolved a rich repertoire of communication, from gesture to sophisticated languages. All of these forms of communication link otherwise separate individuals in such a way that they can share and express their singular experiences and work together collaboratively. In a new study, technology replaces language as a means of communicating by directly linking the activity of human brains. Electrical activity from the brains of a pair of human subjects was transmitted to the brain of a third individual in the form of magnetic signals, which conveyed an instruction to perform a task in a particular manner. This study opens the door to extraordinary new means of human collaboration while, at the same time, blurring fundamental notions about individual identity and autonomy in disconcerting ways. Direct brain-to-brain communication has been a subject of intense interest for many years, driven by motives as diverse as futurist enthusiasm and military exigency. In his book Beyond Boundaries one of the leaders in the field, Miguel Nicolelis, described the merging of human brain activity as the future of humanity, the next stage in our species’ evolution. (Nicolelis serves on Scientific American’s board of advisers.) He has already conducted a study in which he linked together the brains of several rats using complex implanted electrodes known as brain-to-brain interfaces. Nicolelis and his co-authors described this achievement as the first “organic computer” with living brains tethered together as if they were so many microprocessors. The animals in this network learned to synchronize the electrical activity of their nerve cells to the same extent as those in a single brain. The networked brains were tested for things such as their ability to discriminate between two different patterns of electrical stimuli, and they routinely outperformed individual animals. © 2019 Scientific American

Keyword: Robotics; Language
Link ID: 26770 - Posted: 10.30.2019

By Owain Clarke BBC Wales health correspondent World-leading research is helping scientists find new ways of trying to help younger people who have had a stroke get back to work. The study led by Manchester Metropolitan University found the speed a patient can walk is a major factor in determining how likely they are able to return to the workplace. Researchers have been working with physiotherapists and patients in Wales. It includes moving rehabilitation outdoors, including the Brecon Beacons. It is hoped it could lead to new rehabilitation methods being developed to target younger stroke patients. The average age to have a stroke in the UK is 72 for men and 78 for women. But there has been a 40% worldwide rise in people under 65 who have strokes in the last decade, according to the researchers. Image copyright Manchester Metropolitan University Image caption Researchers are studying the skeletons of stroke patients to see how joints perform when they walk What does the science say? It looked at 46 patients across Wales who had a stroke when younger than 65 years old and only 23% were able to return to work It found walking speed was a key predictor of whether a younger adult who has had a stroke could return to work They calculated a walking speed threshold of 0.93m/s (3ft a second) was a good benchmark for the likelihood of returning to work - and as a result this could be a goal set during rehabilitation As well as looking at the best environment for younger patients to recover in, it is now looking at using CGI technology to study joints to find out how stroke patients walk Nikki Tomkinson had a stroke at 53. "The world started shifting" while she was out driving in Cardiff. © 2019 BBC

Keyword: Stroke
Link ID: 26759 - Posted: 10.28.2019

By Sofie Bates Make some noise for the white bellbirds of the Brazilian Amazon, now the bird species with the loudest known mating call. The birds (Procnias albus) reach about 125 decibels on average at the loudest point in one of their songs, researchers report October 21 in Current Biology. Calls of the previous record-holder — another Amazonian bird called the screaming piha (Lipaugus vociferans) — maxed out around 116 decibels on average. This difference means that bellbirds can generate a soundwave with triple the pressure of that made by pihas, says Jeff Podos, a behavioral ecologist at the University of Massachusetts Amherst, who did the research along with ornithologist Mario Cohn-Haft, of the National Institute of Amazon Research in Manaus, Brazil. The team measured sound intensity from three pihas and eight bellbirds. Each sounded off at different distances from the scientists. So to make an accurate comparison, the researchers used rangefinder binoculars, with lasers to measure distance, to determine how far away each bird was. Then, they calculated how loud the sound would be a meter from each bird to crown a winner. The small white bellbird, which weighs less than 250 grams, appears to be built for creating loud sounds, with thick abdominal muscles and a beak that opens extra wide. “Having this really wide beak helps their anatomy be like a musical instrument,” Podos says. Being the loudest may come with a cost: White bellbirds can’t hold a note for long because they run out of air in their lungs. Their loudest call sounds like two staccato beats of an air horn while the calls of screaming pihas gradually build to the highest point. © Society for Science & the Public 2000–2019

Keyword: Sexual Behavior; Hearing
Link ID: 26733 - Posted: 10.22.2019

/ By Nechama Moring The first time my then-partner threw me against a wall, I blamed myself. I was late coming home from work, and I hadn’t even greeted him when I walked through our door. I immediately started complaining about the unwashed dishes and food scraps littering our kitchen. He was angry, shouting at me, and then I felt his arms around me, lifting me slightly. I blacked out when the back of my head hit the kitchen wall. The nature of abuse is that it escalates, and soon my partner was routinely injuring my head, having learned that my hair would effectively hide any bruises or evidence. Over the course of the last year of our relationship, I probably sustained at least three concussions, though none were formally diagnosed. My previously infrequent migraines became almost daily realities, and my work performance tanked, along with my concentration. Simple tasks became overwhelming. Thoughts slipped from my head before I was able to act on them. I lost my ability to form coherent sentences, and I struggled to find words for even mundane items: train, telephone, exit. Exit. I couldn’t plan for shit. I am part of what Eve Valera calls an “invisible public health epidemic” of untreated traumatic brain injuries among survivors of intimate partner violence. Valera, an assistant professor in psychiatry at Harvard Medical School who runs a brain-imaging research lab at Massachusetts General Hospital, estimates that millions of women and people of marginalized genders have suffered from both intimate partner violence and untreated concussions. Yet concussions — a form of traumatic brain injury — are generally viewed as a sports-related problem. Concussion research has focused primarily on the relatively tiny population of men who play professional football. Copyright 2019 Undark

Keyword: Brain Injury/Concussion
Link ID: 26720 - Posted: 10.18.2019

Nicoletta Lanese Cell transplantation therapy offers a promising route to recovery after stroke, but the grafted cells face a harsh environment, with elevated levels of free radicals and proinflammatory cytokines, compromised blood supply, and degraded neural connectivity, says Shan Ping Yu, a neurology researcher at Emory University School of Medicine. He and his colleagues aimed to build a new tool to help stem cells integrate with host neural circuitry after implantation. Scientists have long known that stimulating transplanted neural stem cells encourages them to differentiate into neurons and connect with nearby host cells. Many researchers turn to optogenetics to excite grafted stem cells, but because light travels poorly through dense tissue, the technique requires researchers to stick a laser into their subjects’ brains. So Yu and his coauthors turned instead to a type of enzyme that grants fireflies and jellyfish their glow: luciferase. “These proteins carry their own light, so they do not need a light source,” says Yu. The researchers injected neural progenitor cells that had been derived from induced pluripotent stem cells (iPSCs) into the brains of mouse models of stroke. The cells were genetically engineered to express a fusion protein called luminopsin 3 (LMO3), crafted from the bioluminescent enzyme Gaussia luciferase and the light-sensitive protein VChR1. LMO3 activates in response to either physical light or a molecule called CTZ, which can be delivered noninvasively through the nose into the brain tissue. The fusion protein can be hooked up to either excitatory or inhibitory channels in the neurons to either stimulate or tamp down the cells’ function. Yu and his colleagues dubbed the new technique “optochemogenetics.” © 1986–2019 The Scientist.

Keyword: Stroke
Link ID: 26712 - Posted: 10.17.2019

Using advanced imaging, researchers have uncovered new information regarding traumatic microbleeds, which appear as small, dark lesions on MRI scans after head injury but are typically too small to be detected on CT scans. The findings published in Brain suggest that traumatic microbleeds are a form of injury to brain blood vessels and may predict worse outcomes. The study was conducted in part by scientists at the National Institute of Neurological Disorders and Stroke (NINDS), part of the National Institutes of Health. “Traumatic microbleeds may represent injury to blood vessels that occur following even minor head injury,” said Lawrence Latour, Ph.D., NINDS researcher and senior author of the study. “While we know that damage to brain cells can be devastating, the exact impact of this vascular injury following head trauma is uncertain and requires further study.” This study, which involved researchers from Cold Spring Harbor Laboratory in New York and the Uniformed Services University of the Health Sciences in Bethesda, Maryland, included 439 adults who experienced head injury and were treated in the emergency department. The subjects underwent MRI scans within 48 hours of injury, and again during four subsequent visits. Participants also completed behavioral and outcome questionnaires. The results showed that 31% of all study participants had evidence of microbleeds on their brain scans. More than half (58%) of participants with severe head injury showed microbleeds as did 27% of mild cases. The microbleeds appeared as either linear streaks or dotted, also referred to as punctate, lesions. The majority of patients who exhibited microbleeds had both types. The findings also revealed that the frontal lobes were the brain region most likely to show microbleeds.

Keyword: Brain Injury/Concussion; Stroke
Link ID: 26705 - Posted: 10.16.2019

Nicola Davis A cheap and widely available drug could reduce the risk of death from common head injuries and save tens of thousands of lives each year, researchers say. Tranexamic acid slows down the breakdown of blood clots, and is already used to control heavy bleeding in people who have experienced trauma elsewhere in the body – for example from being shot or stabbed. While some of these patients might also have head injuries, it has remained unclear whether tranexamic acid would help people with head injuries alone. Now scientists say it can – at least in those with mild to moderate traumatic brain injuries – suggesting the drug should be rapidly administered to such patients. “Previous to this research, patients with isolated head injuries were an exception in the policy of giving tranexamic acid to trauma patients as soon as possible,” said Prof Ian Roberts of the London School of Hygiene and Tropical Medicine, who co-led the study. “Now that exception can be removed.” Roberts says the study could have a dramatic impact. “Worldwide it has got the potential to save tens of thousands of lives – this is such a mass problem,” he said. It is estimated that there are about 70m new traumatic brain injuries worldwide every year – a situation commonly caused by motor vehicle crashes, assault or falls. The vast majority are mild or moderate injuries – but these can still prove deadly. The study, which was published in the Lancet medical journal, spanned 29 countries, with the analysis focusing on more than 9,000 patients who were treated within three hours of injury and were randomly allocated to receiving the drug, or a placebo, intravenously. The cost of the total dose of tranexamic acid used in the trial was about £6.20 per person. © 2019 Guardian News & Media Limited

Keyword: Brain Injury/Concussion; Stroke
Link ID: 26704 - Posted: 10.15.2019

By Natalia Sylvester My parents refused to let my sister and me forget how to speak Spanish by pretending they didn’t understand when we spoke English. Spanish was the only language we were allowed to speak in our one-bedroom apartment in Miami in the late 1980s. We both graduated from English as a second language lessons in record time as kindergartners and first graders, and we longed to play and talk and live in English as if it were a shiny new toy. “No te entiendo,” my mother would say, shaking her head and shrugging in feigned confusion anytime we slipped into English. My sister and I would let out exasperated sighs at having to repeat ourselves in Spanish, only to be interrupted by a correction of our grammar and vocabulary after every other word. One day you’ll thank me, my mother retorted. That day has come to pass 30 years later in ordinary places like Goodwill, a Walmart parking lot, a Costco Tire Center. I’m most thankful that I can speak Spanish because it has allowed me to help others. There was the young mother who wanted to know whether she could leave a cumbersome diaper bin aside at the register at Goodwill while she shopped. The cashier shook her head dismissively and said she didn’t understand. It wasn’t difficult to read the woman’s gestures — she was struggling to push her baby’s carriage while lugging the large box around the store. Even after I told the cashier what the woman was saying, her irritation was palpable. The air of judgment is one I’ve come to recognize: How dare this woman not speak English, how dare this other woman speak both English and Spanish. It was a small moment, but it speaks to how easy it would have been for the cashier to ignore a young Latina mother struggling to care for her child had there not been someone around to interpret. “I don’t understand,” she kept saying, though the mother’s gestures transcended language. I choose not to understand is what she really meant. © 2019 The New York Times Company

Keyword: Language
Link ID: 26629 - Posted: 09.21.2019

By Jane E. Brody Late one morning in June, L.J.’s husband got a distressed call from one of his wife’s colleagues. “You’d better come here right away. Your wife is acting weird,” the colleague said. Ms. J., who had just returned from a doctor visit during which she underwent a minor painful procedure, kept asking her colleague for a password despite being told each time that there was none. Ms. J., a 61-year-old arts administrator in New York who did not want her full name used, seemed physically O.K., her colleague recalled. She knew who she was, she walked and talked properly, but what she said made no sense. Plus, Ms. J. could remember nothing that happened after she left the doctor’s office and made her way to work. When Ms. J. continued to behave oddly, the alarmed colleague called 911 and paramedics took her to Mount Sinai St. Luke’s Hospital. The next thing Ms. J. remembers is waking up hours later in a hospital bed and asking, “Where am I? Why am I here?” In the interim, Dr. Carolyn Brockington, a vascular surgeon and director of the hospital’s stroke unit, had examined her and ordered a CT scan and M.R.I. of her brain. All the results were normal. There was no physical weakness, no structural abnormality, no evidence of a stroke, seizure or transient ischemic attack. So, what had happened? A diagnosis of exclusion: Transient global amnesia, often called T.G.A. It is a temporary lapse in memory that can never be retrieved. “It’s as if the brain is on overload and takes a break to recharge,” Dr. Brockington said in an interview. She likened it to rebooting a computer to eradicate an unexplainable glitch. Those with T.G.A. do not experience any alteration in consciousness or abnormal movements. Only the ability to lay down memories is affected. All other parts of the brain appear to be working normally. © 2019 The New York Times Company

Keyword: Learning & Memory; Stroke
Link ID: 26616 - Posted: 09.16.2019

Ruth Williams Tau is a structural protein of brain cells that, in various neurodegenerative conditions and as a result of brain injury, can accumulate as tangled toxic deposits. Using a recently developed in vivo imaging technique, researchers have now examined such tau pathology in the brains of patients who, decades earlier, suffered a single head trauma. The results, presented in Science Translational Medicine last week (September 4), reveal not only that tau accumulation can remain unusually high in such patients, but also that tau abundance correlates with neuronal damage. “It’s an important paper that links a single traumatic brain injury that occurred many years ago to long-term neurodegeneration,” says neuropathologist Thor Stein of Boston University who was not involved in the research. It also “looks at important biomarkers that can be detected in life and that will hopefully, down the road, be useful in a clinical setting for earlier diagnosis.” “It’s a very good and scope-broadening research piece. No one has done a study like this,” adds neurologist Steven DeKosky of the University of Florida who also didn’t take part in the study. “It speaks to the longevity of the pathological changes that can occur to people [after an injury].” Tau tangles, a hallmark of Alzheimer’s disease and other forms of dementia and neurodegeneration, have been found in the brains of some people who have suffered repeated head traumas, such as boxers and NFL football players, as well as in some people who have suffered a single severe traumatic brain injury. © 1986–2019 The Scientist

Keyword: Brain Injury/Concussion; Alzheimers
Link ID: 26600 - Posted: 09.11.2019

By Gregg Easterbrook Sunday marks the opening weekend of the 100th season of the National Football League. Many can’t get enough professional football. During the 2018-19 prime-time TV schedule, three of the four top-rated shows among adults ages 18 to 49 were pro football games. Only “Game of Thrones” bested pigskin in the ratings, and that series concluded, while the N.F.L. goes on. Still, many people presume the sport is in an irreversible tailspin. They think that mounting evidence of brain trauma from concussions, along with the sort of routine brutality that led to last month’s surprise retirement of the 29-year-old quarterback Andrew Luck, will result in football losing its mass appeal. It is also assumed that parents of young athletes will refuse to allow their children to play football at the youth and high school levels, depleting the talent pool. But the future of football looks much brighter than that. It’s true that the game faces multiple challenges involving player safety, especially at the youth and high school levels. But recent reforms in pro, college and high school football appear to be reducing the harm caused by the sport. With a handful of additional reforms at all levels of play, none of which would threaten the fundamental character of the game, the N.F.L.’s second century could look as good as its first. Andrew Luck’s retirement should not be taken as an omen. Generally, N.F.L. longevity is improving. Peyton Manning won the Super Bowl in 2016 at age 39; in February, Tom Brady hoisted the trophy at age 41. The 40-year-old quarterback Drew Brees is likely to be in the Super Bowl mix again this season. Football brought Mr. Luck wealth and celebrity, then he quit while he was ahead. Good for him! Mr. Luck’s injuries were similar in severity to those suffered by the cyclist Alessandro de Marchi during the Tour de France, which often has bicycle crashes, and by the skiing star Lindsey Vonn in many incidents. Athletics cannot be made free of danger of bodily harm. A more significant omen is that N.F.L. neurological damage is not getting worse but rather is in decline. Concussions are down. Numerous rules changes led to the N.F.L. reporting 214 concussions last season, versus 281 the season before. Over the five prior seasons, the average was 243 concussions. © 2019 The New York Times Company

Keyword: Brain Injury/Concussion
Link ID: 26588 - Posted: 09.09.2019

By: Michael L. Lipton, M.D., Ph.D., F.A.C.R. I n December 1960, President-elect John F. Kennedy (JFK) penned The Soft American for Sports Illustrated, in which he described the importance of physical fitness to brain health: “Physical fitness is not only one of the most important keys to a healthy body; it is the basis of dynamic and creative intellectual activity.” As with many of JFK’s public statements, these prescient words remain spot-on today. Neuroscientists continue to uncover the remarkable connection between physical well-being and brain health on many levels: cognitive, behavioral, social, emotional, and more. Boxing, JFK noted, was one of the sports the ancient Greek states pursued to enhance national fitness. But the idea that boxing could promote “dynamic and creative intellectual activity” certainly runs counter to current sensibilities, much like the advertisement for Marlboro cigarettes that graced the back cover of Sports Illustrated at the time. While JFK did not name other collision sports, it seems reasonable to assume that American football would have also qualified as a rung on his ladder to physical fitness and mental well-being. From a 2019 vantage point, it seems shocking that JFK was touting the benefits of sport for brain health while ignoring risks of sport-related brain injury. In 1960, however, when he proposed a comprehensive national program to improve physical fitness, the adverse impact of sport-related head trauma on brain development and function was not on anyone’s radar. Even forty-five years later, when “ Iron Mike ” Webster ’s chronic traumatic encephalopathy (CTE) was reported in the journal Neurosurgery, adverse effects of sport-related head trauma were largely unknown to the general public and, at best, widely under-recognized among the medical community. It is worth noting that Mike Webster himself had never been diagnosed with a concussion or other form of brain injury during his time on the gridiron. Attitudes have changed dramatically since, but in what way has our understanding of head trauma and its adverse effects actually evolved? And most importantly, how can our expanding knowledge inform a viable path forward? © 2019 The Dana Foundation.

Keyword: Brain Injury/Concussion; Development of the Brain
Link ID: 26585 - Posted: 09.07.2019

By Catherine Matacic Italians are some of the fastest speakers on the planet, chattering at up to nine syllables per second. Many Germans, on the other hand, are slow enunciators, delivering five to six syllables in the same amount of time. Yet in any given minute, Italians and Germans convey roughly the same amount of information, according to a new study. Indeed, no matter how fast or slowly languages are spoken, they tend to transmit information at about the same rate: 39 bits per second, about twice the speed of Morse code. “This is pretty solid stuff,” says Bart de Boer, an evolutionary linguist who studies speech production at the Free University of Brussels, but was not involved in the work. Language lovers have long suspected that information-heavy languages—those that pack more information about tense, gender, and speaker into smaller units, for example—move slowly to make up for their density of information, he says, whereas information-light languages such as Italian can gallop along at a much faster pace. But until now, no one had the data to prove it. Scientists started with written texts from 17 languages, including English, Italian, Japanese, and Vietnamese. They calculated the information density of each language in bits—the same unit that describes how quickly your cellphone, laptop, or computer modem transmits information. They found that Japanese, which has only 643 syllables, had an information density of about 5 bits per syllable, whereas English, with its 6949 syllables, had a density of just over 7 bits per syllable. Vietnamese, with its complex system of six tones (each of which can further differentiate a syllable), topped the charts at 8 bits per syllable. © 2019 American Association for the Advancement of Science

Keyword: Language
Link ID: 26576 - Posted: 09.05.2019

By James Gallagher Health and science correspondent, BBC News Scientists have found the first genetic instructions hardwired into human DNA that are linked to being left-handed. The instructions also seem to be heavily involved in the structure and function of the brain - particularly the parts involved in language. The team at the University of Oxford say left-handed people may have better verbal skills as a result. But many mysteries remain regarding the connection between brain development and the dominant hand. What does this tell us? About one in 10 people is left handed. Studies on twins have already revealed genetics - the DNA inherited from parents - has some role to play. However, the specifics are only now being revealed. The research team turned to the UK Biobank - a study of about 400,000 people who had the full sequence of their genetic code, their DNA, recorded. Just over 38,000 were left-handed. And the scientists played a giant game of spot-the-difference to find the regions of their DNA that influenced left-handedness. The study, published in the journal Brain, found four hotspots. "It tells us for the first time that handedness has a genetic component," Prof Gwenaëlle Douaud, one of the researchers, told BBC News. But how does it work? The mutations were in instructions for the intricate "scaffolding" that organises the inside of the body's cells, called the cytoskeleton. Similar mutations that change the cytoskeleton in snails have been shown to lead to the molluscs having an anticlockwise or "lefty" shell. © 2019 BBC

Keyword: Laterality; Genes & Behavior
Link ID: 26575 - Posted: 09.05.2019

Nicola Davis Squirrels eavesdrop on the chatter of songbirds to work out whether the appearance of a predator is cause for alarm, researchers have found. Animals including squirrels have previously been found to tune in to cries of alarm from other creatures, while some take note of “all-clear” signals from another species with which they co-exist to assess danger. But the latest study suggests animals may also keep an ear out for everyday chitchat among other species as a way to gauge whether there is trouble afoot. “This study suggests that eavesdropping on public information about safety is more widespread and broader than we originally thought,” said Prof Keith Tarvin, co-author of the study from Oberlin College, Ohio. “It may not require tight ecological relationships that allow individuals to carefully learn the cues provided by other species,” he added, noting that the grey squirrels and songbirds in the study moved from place to place without regard for the other. Writing in the journal Plos One, Tarvin and colleagues reported on how they made their discovery by observing 67 grey squirrels as they pottered about different areas in the parks and residential regions of Oberlin. After 30 seconds of observing a squirrel, researchers played it a recording of the call of a red-tailed hawk, which lasted a couple of seconds – and their behaviour in the next 30 seconds was monitored. © 2019 Guardian News & Media Limited

Keyword: Animal Communication; Hearing
Link ID: 26573 - Posted: 09.05.2019

By Caroline Parkinson Health editor, BBC News website People who eat vegan and vegetarian diets have a lower risk of heart disease and a higher risk of stroke, a major study suggests. They had 10 fewer cases of heart disease and three more strokes per 1,000 people compared with the meat-eaters. The research, published in the British Medical Journal, looked at 48,000 people for up to 18 years. However, it cannot prove whether the effect is down to their diet or some other aspect of their lifestyle. Diet experts said, whatever people's dietary choice, eating a wide range of foods was best for their health. What does this study add? It analyses data from the EPIC-Oxford study, a major long-term research project looking at diet and health. Half of participants, recruited between 1993 and 2001, were meat-eaters, just over 16,000 vegetarian or vegan, with 7,500 who described themselves as pescatarian (fish-eating). They were asked about their diets, when they joined the study and again in 2010. Medical history, smoking and physical activity were taken into account, Altogether, there were 2,820 cases of coronary heart disease (CHD) and 1,072 cases of stroke - including 300 haemorrhagic strokes, which happen when a weakened blood vessel bursts and bleeds into the brain. The pescatarians were found to have a 13% lower risk of CHD than the meat-eaters, while the vegetarians and vegans had a 22% lower risk. But those on plant-based diets had a 20% higher risk of stroke. The researchers suggested this could be linked to low vitamin B12 levels but said more studies were needed to investigate the connection. It is also possible that the association may have nothing to do with people's diets and may just reflect other differences in the lives of people who do not eat meat. © 2019 BBC

Keyword: Stroke
Link ID: 26572 - Posted: 09.05.2019

Cristina Robinson, Kate Snyder, Nicole Creanza Bonjour! Ni hao! Merhaba! If you move to a new country as an adult, you have to work much harder to get past that initial “hello” in the local language than if you’d moved as a child. Why does it take so much effort to learn a new language later in life? Our human ability to learn language slows down as we get older, but scientists are not sure how or why this happens. An unexpected way to understand this learning process might come from listening to birds sing. After all, songbirds have a lot to learn. They don’t hatch knowing what songs to sing, or how to sing them. Instead, they must learn their species’ song. Young birds listen to adult birds and then practice copying the adult’s song syllables until they sound right. If they fail to learn an appropriate song, male birds will have difficulty attracting mates or defending their territories. How do birds learn to sing? This process of vocal learning is remarkably similar to how humans learn language: Babies listen to their parents speaking and then practice making the same sounds by babbling. Because these processes are so similar, birds have long been used to study vocal learning. However, while these learning processes are similar, the functions of speech and song are quite different. Human speech is complex and made up of many sounds that we use to convey an infinite number of ideas to each other. Birds only need to announce their presence to mates and rivals, yet their song can also be made of a repertoire of hundreds or thousands of unique syllables. What benefit could these more elaborate songs offer males? © 2010–2019, The Conversation US, Inc.

Keyword: Animal Communication; Language
Link ID: 26570 - Posted: 09.04.2019

By Carolyn Wilke In learning to read, squiggles and lines transform into letters or characters that carry meaning and conjure sounds. A trio of cognitive neuroscientists has now mapped where that journey plays out inside the brain. As readers associate symbols with pronunciation and part of a word, a pecking order of brain areas processes the information, the researchers report August 19 in the Proceedings of the National Academy of Sciences. The finding unveils some of the mystery behind how the brain learns to tie visual cues with language (SN Online: 4/27/16). “We didn’t evolve to read,” says Jo Taylor, who is now at University College London but worked on the study while at Aston University in Birmingham, England. “So we don’t [start with] a bit of the brain that does reading.” Taylor — along with Kathy Rastle at Royal Holloway University of London in Egham and Matthew Davis at the University of Cambridge — zoomed in on a region at the back and bottom of the brain, called the ventral occipitotemporal cortex, that is associated with reading. Over two weeks, the scientists taught made-up words written in two unfamiliar, archaic scripts to 24 native English–speaking adults. The words were assigned the meanings of common nouns, such as lemon or truck. Then the researchers used functional MRI scans to track which tiny chunks of brain in that region became active when participants were shown the words learned in training. © Society for Science & the Public 2000–2019

Keyword: Language; Brain imaging
Link ID: 26548 - Posted: 08.27.2019

By Laura Sanders A honeybee that’s been promoted to forager has upgrades in her nerve cells, too. Vibration-sensing nerve cells, or neurons, are more specialized in bees tasked with finding food compared with younger, inexperienced adult bees, researchers report August 26 in eNeuro. This neural refinement may help forager bees better sense specific air vibrations produced by their fellow foragers during waggle dances — elaborate routines that share information about food location, distance and quality (SN Online: 1/24/14). Researchers compared certain neurons in adult bees that had emerged from their cells one to three days earlier to neurons of forager bees, which were older than 10 days. In the foragers, these neurons had more refined shapes, the team found. These vibration-detecting cells, called DL-INT-1 neurons, appear sparser in certain areas, with fewer message-receiving tendrils called dendrites. Refined dendrites may be a sign that these cells are more selective in their connections. And in foragers, these neurons also appear to handle information more efficiently than their counterparts in the young adult bees, experiments with electrodes reveal. These changes in shape and behavior suggest that in foragers, neurons become adept at decoding vibrations produced by other foragers’ waggle dances, say computational neuroscientist Ajayrama Kumaraswamy of the Ludwig-Maximilians-Universität München in Germany and colleagues. But it’s not clear whether foraging experience in the fields or the passage of time itself prompts these refinements. © Society for Science & the Public 2000–2019

Keyword: Learning & Memory; Animal Communication
Link ID: 26543 - Posted: 08.27.2019