Chapter 19. Language and Lateralization

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By Daniel Ackerman Repeatedly heading a soccer ball exacts a toll on an athlete’s brain. But this cost—measured by the volume of brain cells damaged—is five times greater for women than for men, new research suggests. The study provides a biological explanation for why women report more severe symptoms and longer recovery times than men following brain injuries in sports. Previously some researchers had dismissed female players’ complaints because there was little physiological evidence for the disparity, says Michael Lipton, a neuroscientist at the Albert Einstein College of Medicine and a co-author of the paper. Lipton’s team used magnetic resonance imaging to peer into the skulls of 98 adult amateur soccer players—half of them female and half male—who headed the ball with varying frequency during the prior year. For women, eight of the brain’s signal-carrying white matter regions showed structural deterioration, compared with just three such regions in men (damage increased with the number of reported headers). Furthermore, female athletes in the study suffered damage to an average of about 2,100 cubic millimeters of brain tissue, compared with an average of just 400 cubic millimeters in the male athletes. Lipton does not yet know the cause of these sex differences, but he notes two possibilities. Women may suffer stronger whiplash from a cranial blow because they generally have less muscle mass than men to stabilize the neck and skull. Alternatively, a dip in progesterone, a hormone that protects against swelling in the brain, could heighten women’s vulnerability to brain injury during certain phases of their menstrual cycle. © 2018 Scientific American

Keyword: Brain Injury/Concussion; Sexual Behavior
Link ID: 25556 - Posted: 10.10.2018

By Elizabeth Pennisi The melodious call of many birds comes from a mysterious organ buried deep within their chests: a one-of-a-kind voice box called a syrinx. Now, scientists have concluded that this voice box evolved only once, and that it represents a rare example of a true evolutionary novelty. “It’s something that comes out of nothing,” says Denis Dubuole, a geneticist at the University of Geneva in Switzerland who was not involved with the work. “There is nothing that looks like a syrinx in any related animal groups in vertebrates. This is very bizarre.” Reptiles, amphibians, and mammals all have a larynx, a voice box at the top of the throat that protects the airways. Folds of tissue there—the vocal cords—can also vibrate to enable humans to talk, pigs to grunt, and lions to roar. Birds have larynxes, too. But the organ they use to sing their tunes is lower down—where the windpipe splits to go into the two lungs. The syrinx, named in 1872 after a Greek nymph who was transformed into panpipes, has a similar structure: Both are tubes supported by cartilage with folds of tissue. The oldest known syrinx belongs to a bird fossil some 67 million years old; that’s about the same time all modern bird groups became established. To figure out where the bizarre organ came from, Julia Clarke, a paleontologist at the University of Texas in Austin, who made the syrinx discovery in 2013, assembled a team of developmental biologists, evolutionary biologists, and other researchers. © 2018 American Association for the Advancement of Science.

Keyword: Animal Communication; Evolution
Link ID: 25535 - Posted: 10.06.2018

By Sarah Mervosh A simple rule change in Ivy League football games has led to a significant drop in concussions, a study released this week found. After the Ivy League changed its kickoff rules in 2016, adjusting the kickoff and touchback lines by just five yards, the rate of concussions per 1,000 kickoff plays fell to two from 11, according to the study, which was published Monday in the Journal of the American Medical Association. Kickoffs, during which players sprint down the field and can knock into each other at full speed, had previously represented an outsize number of concussions. The study comes amid a broader push to adjust kickoff rules at all levels of football and offers a strong indication that touchbacks can help reduce the risk of head injury in a sport grappling with the competing priorities of entertaining its audience and keeping its players safe. “We see really compelling evidence that, indeed, introducing the experimental kickoff rule seems to be associated with a large reduction in concussions,” said Douglas Wiebe, the lead author of the study and the director of the Penn Injury Science Center at the University of Pennsylvania. In 2015, kickoffs during Ivy League games accounted for 6 percent of all plays, but 21 percent of concussions, the study said. So Ivy League football coaches decided to change the rules to encourage kicks into the end zone. Under the new system, teams kicked off from the 40-yard line, instead of the 35, and touchbacks started from the 20-yard line, rather than the 25. © 2018 The New York Times Company

Keyword: Brain Injury/Concussion
Link ID: 25519 - Posted: 10.02.2018

By Christine Hauser A New Jersey man died after being infected with Naegleria fowleri, also known as the “brain-eating amoeba,” a rare infection that is contracted through the nose in fresh water. The man, Fabrizio Stabile, 29, of Ventnor, N.J., was mowing his lawn on Sept. 16 when he felt ill from a headache, according to his obituary and GoFundMe page. His symptoms worsened and he was taken to the hospital after he became unable to speak coherently. A spinal tap revealed he was infected with the amoeba, and he died on Sept. 21. It is the first confirmed case of the infection in the United States since 2016, an epidemiologist for the Centers for Disease Control and Prevention, Dr. Jennifer Cope, said on Monday. Mr. Stabile fell ill after visiting the BSR Cable Park and Surf Resort, a surf and water park in Waco, Tex., said Kelly Craine, a spokeswoman for the Waco-McLennan County Public Health District. She said in a telephone interview on Monday that the C.D.C. sent epidemiologists to take samples from the park to test for the presence of the amoeba, and those results could come this week. There are no reports of other illnesses at the Waco park, the C.D.C. said. The amoeba is a single-celled organism that can cause a rare infection of the brain called primary amoebic meningoencephalitis, also known as PAM, which is usually fatal. It thrives in warm temperatures and is commonly found in warm bodies of fresh water, such as lakes, rivers and hot springs, the C.D.C. said, though it can also be present in soil. It enters the body through the nose, and it moves on to the brain. Infection typically occurs when people go swimming in lakes and rivers, according to the C.D.C. The amoeba got its nickname because it starts to destroy brain tissue once it reaches the brain, after it is forced up there in a rush of water. Before it enters the body, it happily feasts on the bacteria found in the water. “It turns to using the brain as a food source,” Dr. Cope said. “It is a scary name. It is not completely inaccurate.” © 2018 The New York Times Company

Keyword: Miscellaneous
Link ID: 25515 - Posted: 10.02.2018

By Sandra E. Garcia For years, parents of a Texas boy believed he was mostly nonverbal because of a brain aneurysm he had when he was 10 days old. The boy, Mason Motz, 6, of Katy, Tex., started going to speech therapy when he was 1. In addition to his difficulties speaking, he was given a diagnosis of Sotos syndrome, a disorder that can cause learning disabilities or delayed development, according to the National Institutes of Health. His parents, Dalan and Meredith Motz, became used to how their son communicated. “He could pronounce the beginning of the word but would utter the end of the word,” Ms. Motz said in an interview. “My husband and I were the only ones that could understand him.” That all changed in April 2017, when Dr. Amy Luedemann-Lazar, a pediatric dentist, was performing unrelated procedures on Mason’s teeth. She noticed that his lingual frenulum, the band of tissue under his tongue, was shorter than is typical and was attached close to the tip of his tongue, keeping him from moving it freely. Dr. Luedemann-Lazar ran out to the waiting room to ask the Motzes if she could untie Mason’s tongue using a laser. After a quick Google search, the parents gave her permission to do so. Dr. Luedemann-Lazar completed the procedure in 10 seconds, she said. After his surgery, Mason went home. He had not eaten all day. Ms. Motz heard him say: “I’m hungry. I’m thirsty. Can we watch a movie?” “We’re sitting here thinking, ‘Did he just say that?’” Ms. Motz said. “It sounded like words.” © 2018 The New York Times Company

Keyword: Language
Link ID: 25510 - Posted: 10.01.2018

By Katie Hafner NEW HAVEN, Conn. — By now, Sally and Bennett Shaywitz might have retired to a life of grandchild-doting and Mediterranean-cruising. Instead, the Shaywitzes — experts in dyslexia at Yale who have been married to each other for 55 years — remain as focused as ever on a research endeavor they began 35 years ago. Sally, 76, and Bennett, 79, both academic physicians, run the Yale Center for Dyslexia and Creativity. Their goal is not just to widen understanding of the scientific underpinnings of dyslexia, the most common learning disorder in the United States, but to push for public policies aligned with that knowledge. For years, dyslexia was largely misunderstood as a reading problem that caused children to reverse letters, and often was seen as a sign of laziness, stupidity or bad vision. The Shaywitzes’ work has shown there is no link between dyslexia and intelligence, and that dyslexia is not something one outgrows. Their research has found that it affects one in five people, yet even now many never receive a formal diagnosis. “There is an epidemic of reading failure that we have the scientific evidence to treat effectively and yet we are not acknowledging,” Sally said. Working from unprepossessing offices on the Yale School of Medicine campus, the Shaywitzes are now updating one of their signal achievements, a study they started in 1983 following 445 five-year-olds in Connecticut. It was the first study to examine reading continually from childhood through adulthood. The Connecticut Longitudinal Study, or C.L.S., has not only established the prevalence of dyslexia but also has demonstrated that it affects boys and girls in roughly equal numbers. The couple recently began a new phase of the study, administering reading tests to 375 of the participants, who are now in their 40s. They have no planned completion date. © 2018 The New York Times Company

Keyword: Dyslexia; Development of the Brain
Link ID: 25480 - Posted: 09.22.2018

By Douglas Quenqua For solitary animals, giant pandas have an awful lot to say to one another. Their vocal repertoire comprises more than a dozen distinct grunts, barks and squeaks, most of which amount to some version of “leave me alone.” But when mating season rolls around, both male and female giant pandas turn to their preferred come-hither call: a husky, rapid vibrato that’s commonly known as the bleat. The bleat not only alerts other pandas to the presence of an available mate, it contains important information about the vocalist’s size and identity. Given the dense bamboo thicket that limits visual contact in most panda habitats and the brevity of panda mating season — females ovulate just once a year and can conceive for only a few days — the pandas’ ability to perceive the bleat is critical to reproduction among this once-endangered species. Now, researchers have determined that the bleat works best as a local call. A panda can discern aspects of a caller’s identity. like its size, from a bleat within about 65 feet, but the caller’s gender is only perceptible within about 33 feet, according to a study published Thursday in Scientific Reports. Megan Owen, a conservation ecologist at the San Diego Zoo Institute for Conservation Research and an author of the study, offered a human analogy for how this ability works. “If you’re walking into a crowded room and someone calls out your name, there’s a certain point where you can identify who that is, or maybe you can identify that it’s a male or female that is calling your name,” she said. “There’s information that’s encoded in that call, but that information degrades over distance.” To conduct the study, Dr. Owen and her colleagues — including Ben Charlton, another San Diego institute researcher who has studied panda bleats — obtained recordings of giant pandas from Chengdu, China, during breeding season. They then played those recordings through a speaker in a section of the San Diego Zoo Safari Park that contains bamboo similar in type and density to a typical panda habitat. By placing recording devices throughout the bamboo, the researchers were able to capture and analyze the bleats from various distances. © 2018 The New York Times Company

Keyword: Sexual Behavior; Animal Communication
Link ID: 25475 - Posted: 09.21.2018

By Perri Klass, M.D. The Centers for Disease Control and Prevention released a major new guideline on diagnosing and managing head injuries in children on Sept. 4, the product of years of work and extensive evidence review by a large working group of specialists in fields ranging from emergency medicine and epidemiology to sports injuries to neurology and neurosurgery. The guideline, which is the first from the C.D.C. that is specific to mild brain injury in children, advises against the long recovery period, isolated in a dark, quiet room, that has sometimes been used in treatment. “The brain is a somewhat gelatinous, even trembling organ which houses our consciousness,” said Dr. Angela Lumba-Brown, a pediatric emergency medicine specialist who is the co-director of the Stanford Concussion and Brain Performance Center, and the first author of the guideline. “It does have resilience, but there are periods in life when it is particularly vulnerable.” Having a truly evidence-based guideline should help clinicians personalize the care that children receive and the ways they gradually reintegrate into activities and sports, she said, rather than applying rigid rules — and should generally encourage an earlier return to non-risky activity. The guideline focuses specifically on what is called mTBI, for “mild traumatic brain injury,” which might otherwise be called concussion. There are studies which show that the way that people think about these head injuries — the kids, the parents, the coaches, the doctors — can actually be affected by which term is used, so that what is called a concussion may not be taken as seriously as what is called a mild traumatic brain injury. Some of these injuries are related to sports, but many involve falls from playground equipment, or in the home, as young children explore their developing physical abilities. © 2018 The New York Times Company

Keyword: Brain Injury/Concussion; Development of the Brain
Link ID: 25459 - Posted: 09.17.2018

By Sarah Kaplan and Joel Achenbach A series of attacks with a microwave weapon is the latest theory for what could have sickened or distressed roughly two dozen people associated with the U.S. Embassy in Cuba over the past two years. The alleged attacks dominated a House Foreign Affairs subcommittee hearing on Cuba policy Thursday afternoon. But a panel of State Department officials said there is still no explanation for the reported injuries. “We’re seeing a unique syndrome. I can’t even call it a syndrome. It’s a unique constellation of symptoms and findings, but with no obvious cause,” testified Charles Rosenfarb, the State Department’s medical director. Despite the buzz over microwaves, advanced in news reports in recent days, experts warn that caution is in order. There’s an old scientific aphorism that extraordinary claims require extraordinary evidence. “And they’re not giving the extraordinary evidence. They’re not giving any evidence,” said physicist Peter Zimmerman, an arms control expert and former scientific adviser to the State Department and Senate Foreign Relations Committee. No microwave weapon that affects the brain is known to exist. The FBI has investigated the Cuba cases and found no evidence of a plot. Searches of the U.S. Embassy and other locations in Havana have turned up no sign of a weapon. © 1996-2018 The Washington Post

Keyword: Brain Injury/Concussion
Link ID: 25424 - Posted: 09.08.2018

By William J. Broad During the Cold War, Washington feared that Moscow was seeking to turn microwave radiation into covert weapons of mind control. More recently, the American military itself sought to develop microwave arms that could invisibly beam painfully loud booms and even spoken words into people’s heads. The aims were to disable attackers and wage psychological warfare. Now, doctors and scientists say such unconventional weapons may have caused the baffling symptoms and ailments that, starting in late 2016, hit more than three dozen American diplomats and family members in Cuba and China. The Cuban incidents resulted in a diplomatic rupture between Havana and Washington. The medical team that examined 21 affected diplomats from Cuba made no mention of microwaves in its detailed report published in JAMA in March. But Douglas H. Smith, the study’s lead author and director of the Center for Brain Injury and Repair at the University of Pennsylvania, said in a recent interview that microwaves were now considered a main suspect and that the team was increasingly sure the diplomats had suffered brain injury. “Everybody was relatively skeptical at first,” he said, “and everyone now agrees there’s something there.” Dr. Smith remarked that the diplomats and doctors jokingly refer to the trauma as the immaculate concussion. Strikes with microwaves, some experts now argue, more plausibly explain reports of painful sounds, ills and traumas than do other possible culprits — sonic attacks, viral infections and contagious anxiety. In particular, a growing number of analysts cite an eerie phenomenon known as the Frey effect, named after Allan H. Frey, an American scientist. Long ago, he found that microwaves can trick the brain into perceiving what seem to be ordinary sounds. The false sensations, the experts say, may account for a defining symptom of the diplomatic incidents — the perception of loud noises, including ringing, buzzing and grinding. Initially, experts cited those symptoms as evidence of stealthy attacks with sonic weapons. © 2018 The New York Times Company

Keyword: Brain Injury/Concussion; Hearing
Link ID: 25410 - Posted: 09.01.2018

Ian Sample Science editor Claims that US diplomats suffered mysterious brain injuries after being targeted with a secret weapon in Cuba have been challenged by neurologists and other brain specialists. A medical report commissioned by the US government, published in March, found that staff at the US embassy in Havana suffered concussion-like brain damage after hearing strange noises in homes and hotels, but doctors from the US, the UK and Germany have contested the conclusions. In four separate letters to the Journal of the American Medical Association, which published the original medical study, groups of doctors specialising in neurology, neuropsychiatry and neuropsychology described what they believed were major flaws in the study. Among the criticisms, published on Tuesday, are that the University of Pennsylvania team which assessed the diplomats misinterpreted test results, overlooked common disorders that might have made the workers feel sick, or dismissed psychological explanations for their symptoms. Doctors at the University of Pennsylvania defended their report in a formal response in the journal, but the specialists told the Guardian they stood by their criticisms. The US withdrew more than half of its Havana diplomats last year and expelled 15 Cubans after 24 embassy staff and family reported a bizarre list of symptoms, ranging from headaches, dizziness and difficulties in sleeping, to problems with concentration, balance, vision and hearing. Many said their symptoms developed after they heard strange noises, described as cicada-like chirps, grinding, or the buffeting caused by an open window in the car. © 2018 Guardian News and Media Limited

Keyword: Brain Injury/Concussion; Hearing
Link ID: 25334 - Posted: 08.15.2018

by Amy Ellis Nutt Traumatic brain injury is the leading cause of death and disability in young adults in the developed world. Suicide is the second leading cause of death for young people ages 15 to 24. Though the reasons for any particular suicide are often inscrutable, research published Tuesday in the Journal of the American Medical Association suggests that at least a fraction of the blame could be placed on traumatic brain injuries. Researchers found that of the nearly 7.5 million people who make up the population of Denmark, more than 34,500 deaths between 1980 and 2014 were by suicide. Approximately 10 percent of those who took their own lives had also suffered a medically documented traumatic brain injury. The statistical analysis was conducted using the Danish Cause of Death registry. “Individuals with mild TBI, with concussion, had an elevated suicide risk by 81 percent,” said Trine Madsen of the Danish Research Institute of Suicide Prevention, one of the authors of the study. “But individuals with severe TBI had a higher suicide risk that was more than double [the risk of someone with no TBI].” Three factors most strongly predicted the risk of suicide: the severity of the traumatic brain injury, a first incidence occurring in young adulthood and discharge from a hospital for a TBI in the previous six months. Seena Fazel, a forensic psychiatrist at the University of Oxford, has studied TBIs and health risks, including mental health issues, in large Scandinavian populations as well. “What is important in this study,” Fazel said, “is that we can say that these risks are also found when TBIs are sustained in childhood.” © 1996-2018 The Washington Post

Keyword: Brain Injury/Concussion; Depression
Link ID: 25330 - Posted: 08.15.2018

By Victoria Gill Science correspondent, BBC News Our primate cousins have surprised and impressed scientists in recent years, with revelations about monkeys' tool-using abilities and chimps' development of complex sign language. But researchers are still probing the question: why are we humans the only apes that can talk? That puzzle has now led to an insight into how different non-human primates' brains are "wired" for vocal ability. A new study has compared different primate species' brains. It revealed that primates with wider "vocal repertoires" had more of their brain dedicated to controlling their vocal apparatus. That suggests that our own speaking skills may have evolved as our brains gradually rewired to control that apparatus, rather than purely because we're smarter than non-human apes. Humans and other primates have very similar vocal anatomy - in terms of their tongues and larynx. That's the physical machinery in the throat which allows us to turn air into sound. So, as lead researcher Dr Jacob Dunn from Anglia Ruskin University in Cambridge explained, it remains a mystery that only human primates can actually talk. "That's likely due to differences in the brain," Dr Dunn told BBC News, "but there haven't been comparative studies across species." So how do our primate brains differ? That comparison is exactly what Dr Dunn and his colleague Prof Jeroen Smaers set out to do. They ranked 34 different primate species based on their vocal abilities - the number of distinct calls they are known to make in the wild. They then examined the brain of each species, using information from existing, preserved brains that had been kept for research. © 2018 BBC

Keyword: Language; Evolution
Link ID: 25314 - Posted: 08.10.2018

Laura Sanders A career of hard hits to the head doesn’t inevitably lead to brain decline, a small study of former football and hockey pros suggests. The results counter a specter raised by other studies on pro football players’ brains after death. The new findings come from extensive brain scans and behavioral tests of 21 retired athletes — football players from New York’s Buffalo Bills and hockey players from the Buffalo Sabres. In a series of papers published August 7 in the Journal of Head Trauma Rehabilitation, researchers report finding no signs among the athletes of early dementia or mental slipping. Those symptoms are early hallmarks of the brain disease chronic traumatic encephalopathy, or CTE, which can be diagnosed by a brain examination only after death. Such studies involving living subjects “are exactly what we really need,” says cognitive neuroscientist and psychologist Carrie Esopenko of Rutgers University in Newark, N.J. “They are really going to help us understand what’s going on in these lives, rather than what’s happening when they’re dead.” Using a battery of clinical tests, researchers at the University at Buffalo measured brain function and mental health, while also investigating other aspects of the ex-players’ health, such as diet, body mass index and history of drug and alcohol use. The team then compared the results with the same measures taken for 21 noncontact athletes, including runners and cyclists. Participating football players and hockey players expected bad news. They “were pretty much their own worst critics,” believing themselves to be impaired, says coauthor and psychiatrist Barry Willer. |© Society for Science & the Public 2000 - 2018.

Keyword: Brain Injury/Concussion
Link ID: 25308 - Posted: 08.08.2018

Sukanya Charuchandra R. Liu et al., “Perception of social interaction compresses subjective duration in an oxytocin-dependent manner,” eLife, 7:e32100, 2018. External stimuli can affect our perception of time. Researchers in China set out to test whether a person’s social skills and perception of social interactions alters their sense of time. Subjects viewed two motion sequences depicting two humans composed of dots of light. The first video clip showed sociable behavior between the figures, such as passing an object, while the second showed no interaction—the figures moved independently of each other. The subjects had to indicate which clip appeared to last longer. Overall, volunteers found the clips with communicative behavior to be shorter, even when that wasn’t true. This “temporal compression effect” was not as pronounced in less sociable test subjects, as measured by their Autism Spectrum Quotient, a questionnaire-based assessment that determines where people fall on the neurotypical or autistic scale. “It not only highlights the idiosyncrasy of subjective time but also demonstrates that our perception of the world (something as basic as time) is ingrained with our personality traits,” writes coauthor Wen Zhou of the Chinese Academy of Sciences’ Institute of Psychology in an email to The Scientist. © 1986 - 2018 The Scientist

Keyword: Hormones & Behavior; Autism
Link ID: 25306 - Posted: 08.08.2018

Tina Hesman Saey Humans’ gift of gab probably wasn’t the evolutionary boon that scientists once thought. There’s no evidence that FOXP2, sometimes called “the language gene,” gave humans such a big evolutionary advantage that it was quickly adopted across the species, what scientists call a selective sweep. That finding, reported online August 2 in Cell, follows years of debate about the role of FOXP2 in human evolution. In 2002, the gene became famous when researchers thought they had found evidence that a tweak in FOXP2 spread quickly to all humans — and only humans — about 200,000 years ago. That tweak swapped two amino acids in the human version of the gene for ones different than in other animals’ versions of the gene. FOXP2 is involved in vocal learning in songbirds, and people with mutations in the gene have speech and language problems. Many researchers initially thought that the amino acid swap was what enabled humans to speak. Speech would have given humans a leg up on competition from Neandertals and other ancient hominids. That view helped make FOXP2 a textbook example of selective sweeps. Some researchers even suggested that FOXP2 was the gene that defines humans, until it became clear that the gene did not allow humans to settle the world and replace other hominids, says archeaogeneticist Johannes Krause at the Max Planck Institute for the Science of Human History in Jena, Germany, who was not involved in the study. “It was not the one gene to rule them all.” |© Society for Science & the Public 2000 - 2018

Keyword: Language; Genes & Behavior
Link ID: 25293 - Posted: 08.04.2018

Matthew Warren The evolution of human language was once thought to have hinged on changes to a single gene that were so beneficial that they raced through ancient human populations. But an analysis now suggests that this gene, FOXP2, did not undergo changes in Homo sapiens’ recent history after all — and that previous findings might simply have been false signals. “The situation’s a lot more complicated than the very clean story that has been making it into textbooks all this time,” says Elizabeth Atkinson, a population geneticist at the Broad Institute of Harvard and MIT in Cambridge, Massachusetts, and a co-author of the paper, which was published on 2 August in Cell1. Originally discovered in a family who had a history of profound speech and language disorders, FOXP2 was the first gene found to be involved in language production2. Later research touted its importance to the evolution of human language. A key 2002 paper found that humans carry two mutations to FOXP2 not found in any other primates3. When the researchers looked at genetic variation surrounding these mutations, they found the signature of a ‘selective sweep’ — in which a beneficial mutation quickly becomes common across a population. This change to FOXP2 seemed to have happened in the past 200,000 years, the team reported in Nature. The paper has been cited hundreds of times in the scientific literature. © 2018 Springer Nature Limited.

Keyword: Language; Genes & Behavior
Link ID: 25292 - Posted: 08.04.2018

By Michael Erard , Catherine Matacic If you want a no-fuss, no-muss pet, consider the Bengalese finch. Dubbed the society finch for its friendliness, breeders often use it to foster unrelated chicks. But put the piebald songbird next to its wild ancestor, the white-rumped munia, and you can both see and hear the differences: The aggressive munia tends to be darker and whistles a scratchy, off-kilter tune, whereas the pet finch warbles a melody so complex that even nonmusicians may wonder how this caged bird learned to sing. All this makes the domesticated and wild birds a perfect natural experiment to help explore an upstart proposal about human evolution: that the building blocks of language are a byproduct of brain alterations that arose when natural selection favored cooperation among early humans. According to this hypothesis, skills such as learning complex calls, combining vocalizations, and simply knowing when another creature wants to communicate all came about as a consequence of pro-social traits like kindness. If so, domesticated animals, which are bred to be good-natured, might exhibit such communication skills too. The idea is rooted in a much older one: that humans tamed themselves. This self-domestication hypothesis, which got its start with Charles Darwin, says that when early humans started to prefer cooperative friends and mates to aggressive ones, they essentially domesticated themselves. Along with tameness came evolutionary changes seen in other domesticated mammals—smoother brows, shorter faces, and more feminized features—thanks in part to lower levels of circulating androgens (such as testosterone) that tend to promote aggression. © 2018 American Association for the Advancement of Science.

Keyword: Language; Evolution
Link ID: 25289 - Posted: 08.03.2018

Laura Sanders Among amateur players who headed a similar number of balls, women had more signs of microscopic damage in their brains’ white matter than men, scientists report July 31 in Radiology. Female athletes are known to have worse symptoms after brain injuries than male athletes, but a clear head-to-head comparison of post-heading brains hadn’t been done until now. From 2013 to 2016, study coauthor Michael Lipton of Albert Einstein College of Medicine in Bronx, N.Y., and colleagues recruited 98 soccer players from amateur teams, including from colleges. The researchers then compared male and female players who headed the ball a similar number of times over the past year. For men, that median estimate was 487 headers. Women had an estimated median of 469 headers. Despite those similar numbers of head knocks, women’s brains had more spots that showed signs of microscopic damage. A type of magnetic resonance imaging scan called diffusion tensor imaging identified brain regions with changes in white matter, bundles of message-sending fibers. In some cases, those altered spots indicated possible damage to nerve cell axons and myelin, a protective coating that speeds neural signals along. In men, only three brain regions showed potential damage associated with heading frequency. In women, eight regions showed signs of damage with frequent heading. These brain changes weren’t enough to cause symptoms in the amateur soccer players. But repeated blows to the brain can contribute to memory loss and chronic traumatic encephalopathy, a disorder found in professional football players, soldiers and others whose brains suffer repetitive trauma (SN: 7/13/13, p. 18). |© Society for Science & the Public 2000 - 2018.

Keyword: Brain Injury/Concussion; Sexual Behavior
Link ID: 25281 - Posted: 08.01.2018

By Stephen T. Casper The case report is dead. At least, it seems all but so in the realm of evidence-based medicine. It is thus thoroughly refreshing to read Helen Thomson’s Unthinkable: An Extraordinary Journey Through the World’s Strangest Brains and Eric R. Kandel’s The Disordered Mind: What Unusual Brains Tell Us About Ourselves, two ambitious books that draw on clinical profiles to tell stories about our brains and minds. Thomson’s memoir aims to help us understand our brains through stories about exceptional others, who, she argues, may serve as proxies for ourselves. Kandel’s book argues from neuroscience research and individual illness experiences for a biologically informed account of mind and brain. Both authors are unapologetic in their focus on what might be dismissed as merely anecdotal. Each foregrounds neurological and psychiatric patient narratives and experiences and from these draws out larger philosophical and scientific lessons. By profiling and seeking meaning in individuals with curious neurological conditions, Thomson’s Unthinkable follows a well-worn literary path but revitalizes the genre with an original and subtle shift to the personal. Perfected by neurologist Oliver Sacks, Thomson’s technique was invented before the 19th century but most famously pioneered in the 20th century by such eminent neurologists as Morton Prince, Sigmund Freud, and Alexander Luria. Where those authors represented patients as medical mysteries or as object lessons in physiology and philosophy, Thomson finds a timelier focus that corresponds with the growing advocacy for, and social attention to, individual patients’ rights. Unlike her predecessors in the genre, Thomson enters her subject’s lives—their restaurants, homes, families, communities, and online selves. © 2017 American Association for the Advancement of Science

Keyword: Attention
Link ID: 25278 - Posted: 08.01.2018