Chapter 15. Brain Asymmetry, Spatial Cognition, and Language

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By Aylin Woodward Not in my backyard. Territorial songbirds in New Zealand reacted more aggressively towards males encroaching on their territory if those rivals sang more complicated songs. The tui birds perceived these snappy singers as greater territorial threats than their simpler singing counterparts. Birdsong has two main functions: defending a territory and attracting a mate, says Samuel Hill at Massey University in Auckland, New Zealand. For tui (Prosthemadera novaeseelandiae), territory defence is a key concern. “There are flowering and fruiting trees year round in New Zealand, so the tui always have resources to defend,” says Hill. This explains why “they natter all year round”. Warbling away takes lots of energy, so males may be showing off their physical endurance to females. Long and complicated songs may also be a sign of skill, as to sing them birds must use superfast vocal muscles to control rapid acoustic changes. In other songbirds, like zebra finches, females prefer males that sing harder songs. This hasn’t been tested in tui, but Hill says the complexity of a male’s song is probably a proxy for more relevant measures of his quality, like body condition and cognitive ability. If that is so, Hill reasoned, breeding male tui would take umbrage at potential rivals singing at the edge of their territory, particularly if their songs were complex and they were therefore strong competitors. © Copyright New Scientist Ltd.

Keyword: Sexual Behavior; Animal Communication
Link ID: 24227 - Posted: 10.21.2017

Aimee Cunningham To guard against the dangers of concussions, by 2014, all 50 states and the District of Columbia had enacted laws to protect young athletes. More than 2½ years after these laws went on the books, repeat concussions began to decline among high school athletes, researchers report online October 19 in the American Journal of Public Health. Researchers reviewed concussion data from 2005 to 2016 collected in an online system for sports injuries from a nationally representative sample of U.S. high schools. An estimated nearly 2.7 million reported concussions occurred during that time — an annual average of 39.8 concussions per 100,000 times a player hit the field for practice or games — among athletes in nine sports: football, basketball, soccer, baseball or wrestling for boys, and basketball, soccer, softball and volleyball for girls. Overall, the rate of new and recurrent concussions was climbing before the implementation of traumatic brain injury laws and continued to rise immediately after. But then, 2.6 years after the laws went into effect, the rate of recurrent concussions dropped roughly 10 percent, the authors say. New concussions showed a slight downturn beginning 3.8 years post-law. Most of the new laws require education on symptoms and signs of concussions for athletes, coaches and parents. So greater awareness of symptoms rather than an actual uptick in injuries may be behind the initial increase in reported concussions in the post-statute period. And the drop in recurrent concussions may be due to the laws’ provisions that take athletes off the field after a concussion and keep them off until approved by a medical provider. While the trends suggest that laws are having an impact, the researchers say, measures that focus on preventing concussions — not only taking steps after they happen — are needed. |© Society for Science & the Public 2000 - 2017.

Keyword: Brain Injury/Concussion
Link ID: 24220 - Posted: 10.20.2017

By GRETCHEN REYNOLDS Here’s yet another reason to protect young athletes from head trauma: A large-scale new study found that concussions in adolescents can increase the risk of later developing multiple sclerosis. The risk of multiple sclerosis, or M.S., an autoimmune nervous system disorder with an unknown cause, was especially high if there were more than one head injury. The overall chances that a young athlete who has had one or more head injuries will develop multiple sclerosis still remain low, the study’s authors point out. But the risk is significantly higher than if a young person never experiences a serious blow to the head. The drumbeat of worrying news about concussions and their consequences has been rising in recent years, as most of us know, especially if we have children who play contact sports. Much of this concern has centered on possible links between repeated concussions and chronic traumatic encephalopathy, a serious, degenerative brain disease that affects the ability to think. But there have been hints that head trauma might also be linked to the development of other conditions, including multiple sclerosis. Past studies with animals have shown that trauma to the central nervous system, including the brain, may jump-start the kind of autoimmune reactions that underlie multiple sclerosis. (In the disease, the body’s immune system begins to attack the fatty sheaths that enwrap and protect nerve fibers, leaving them vulnerable to damage and scarring.) © 2017 The New York Times Company

Keyword: Brain Injury/Concussion; Multiple Sclerosis
Link ID: 24219 - Posted: 10.19.2017

By Rebecca Robbins, LAS VEGAS — It’s a study that probably couldn’t be conducted anywhere other than this hot spot for professional combatants, where marquee fights are about as common as Celine Dion concerts. Researchers have enrolled close to 700 mixed martial arts fighters and boxers, both active and retired, in the past six years. The ambitious goal: to learn to identify early signs of trauma-induced brain damage from subtle changes in blood chemistry, brain imaging, and performance tests — changes that may show up decades before visible symptoms such as cognitive impairment, depression, and impulsive behavior. Among the participants is 29-year-old Gina Mazany. She has a streak of pinkish-purple hair, a tattoo of a pterodactyl with a cheeseburger in its beak, and a reputation as a formidable MMA fighter worthy of her nickname, Gina Danger. Once a year, she undergoes a battery of medical tests here at the Lou Ruvo Center for Brain Health, an outpost of the Cleveland Clinic, to help suss out the toll of a career marked by concussions and blows to the head. “I’m one of their guinea pigs,” she said. Last month, researchers at Boston University made a splash when they identified high levels of a protein called CCL11 in the brain and spinal fluid of deceased football players with the degenerative brain disease known as chronic traumatic encephalopathy. Cleveland Clinic researchers are taking a different tack: They’re monitoring professional fighters while they’re still alive — and, most of the time, while they’re still fighting. By repeating a series of tests year after year, they hope to pick up on changes that might predict development of CTE. © 2017 Scientific American

Keyword: Brain Injury/Concussion
Link ID: 24209 - Posted: 10.18.2017

French scientists claim they may have found a physiological, and seemingly treatable, cause for dyslexia hidden in tiny light-receptor cells in the human eye. In people with the condition, the cells were arranged in matching patterns in both eyes, which may be to blame for confusing the brain by producing “mirror” images, the co-authors wrote in the journal Proceedings of the Royal Society B. In non-dyslexic people, the cells are arranged asymmetrically, allowing signals from the one eye to be overridden by the other to create a single image in the brain. “Our observations lead us to believe that we indeed found a potential cause of dyslexia,” said the study’s co-author, Guy Ropars, of the University of Rennes. It offers a “relatively simple” method of diagnosis, he added, by simply looking into a subject’s eyes. Furthermore, “the discovery of a delay (of about 10 thousandths of a second) between the primary image and the mirror image in the opposing hemispheres of the brain, allowed us to develop a method to erase the mirror image that is so confusing for dyslexic people” – using an LED lamp. Like being left- or right-handed, human beings also have a dominant eye. As most of us have two eyes, which record slightly different versions of the same image, the brain has to select one of the two, creating a “non-symmetry”. Many more people are right-eyed than left, and the dominant eye has more neural connections to the brain than the weaker one. Image signals are captured with rods and cones in the eye – the cones being responsible for colour. © 2017 Guardian News and Media Limited

Keyword: Dyslexia; Vision
Link ID: 24208 - Posted: 10.18.2017

By Diana Kwon Recovering from a concussion typically takes female athletes more than twice as long as males, according to a new study that tracked hundreds of teenagers active in sports. The finding adds to a growing body of evidence that vulnerability to this injury—and aspects of the healing process—may vary by sex. A handful of studies published since the mid-2000s have suggested that girls in high school and college may sustain a higher rate of these injuries on the playing field than boys do, and investigations over the last few years have indicated they may also take longer to recover. As a result, when sports medicine researchers and experts convened in Berlin last fall for the 5th International Consensus Conference on Concussion in Sport, their subsequent statement cited evidence girls were more likely to suffer concussions that required a more lengthy recovery period than their male counterparts did. “But there wasn’t enough data to [definitively] say that this was the case,” says John Neidecker, a sports medicine physician with the Orthopaedic Specialists of North Carolina. “We thought that we'd take a look back at the athletes that we saw over a three-year period and actually [provide] some objective data.” Neidecker and his colleagues analyzed the medical records of 212 middle and high school athletes who visited a sports medicine practice in southern New Jersey—110 boys and 102 girls—who had experienced their first concussion while playing an organized sport such as football, field hockey or wrestling. (Only initial head injuries were considered to rule out the possible effect of prior incidents.) Their analysis revealed the median recovery time for girls was 28 days—more than double that of boys, which was 11 days. The results appeared Monday inThe Journal of the © 2017 Scientific American

Keyword: Brain Injury/Concussion; Sexual Behavior
Link ID: 24142 - Posted: 10.03.2017

By PERRI KLASS, M.D. More than 30 years ago, my toddler stood up in his stroller, evading the various belts and restraints, and took a dramatic header down onto the pavement. He cried right away — a good thing, because it meant he didn’t lose consciousness, and by the time we got home, he seemed to be consoled, though he was already developing a major goose egg. I was a fourth-year medical student at the time and called the pediatric practice at University Health Services, and explained, somewhat frantically, that I was due to get on a flight to California with him in a couple of hours; I was going out for my all-important residency interviews. No problem, said the sympathetic doctor on call, all those years ago. You’re a medical student, you must have a penlight. Just take it along on the plane, and make sure you wake your son up every two hours and check that his pupils are equal, round and reactive to light. And he wished me good luck at my interviews. I hung up, much comforted. It was not until we were sitting on the airplane, me with my penlight in my pocket, that it occurred to me to wonder what I was supposed to do if somewhere over the Midwest, his pupils were not equal, round and reactive. We’ve gotten better, I hope, at some of the advice we give, but for pediatricians and for parents, head trauma in children is still an occasion for difficult decision making. Unlike broken limbs, usually detected because of pain and clearly diagnosed with X-rays, head injuries are tricky to diagnose and manage. In many cases where the concern is concussion, there is no medication or surgery that can make a difference — the primary treatment is rest. Public awareness over the ties between concussions and later problems for children, and publicity about chronic traumatic encephalopathy in athletes may be making parents even more anxious about treating head injuries. But with increasing concern in recent years about the radiation risk to children of CT scans, doing a head CT just to reassure a worried parent — or even a worried doctor — is generally seen as bad medicine; if you’re giving a child a significant dose of possibly dangerous radiation, you need to have some evidence that you may actually be doing something necessary for that child’s safety. © 2017 The New York Times Company

Keyword: Brain Injury/Concussion; Brain imaging
Link ID: 24135 - Posted: 10.02.2017

By GINA KOLATA Otto F. Warmbier, the college student imprisoned in North Korea and returned to the United States in a vegetative state, suffered extensive brain damage following interrupted blood flow and a lack of oxygen, according to the coroner who examined his body. But an external examination and “virtual autopsy” conducted by the coroner’s office in Hamilton County, Ohio, could not determine how his circulation had been cut off. “All we can do is theorize, and we hate to theorize without science backing us up,” Dr. Lakshmi Sammarco, the county coroner, said in an interview Thursday. Mr. Warmbier, 22, an undergraduate at the University of Virginia, was convicted in March 2016 of trying to steal a propaganda poster while on a trip to North Korea and sentenced to 15 years of hard labor. He was flown back to the United States in June in a vegetative state. North Korean officials said Mr. Warmbier’s condition was caused by sleeping pills and botulism, a diagnosis that medical experts doubted. He died six days later at the University of Cincinnati Medical Center. His parents requested that a full autopsy not be performed. On Tuesday, during an appearance on the television show “Fox & Friends,” Fred Warmbier said that his son had been “tortured” and described North Korean officials as “terrorists.” After the interview, President Trump said in a tweet that Mr. Warmbier “was tortured beyond belief by North Korea.” On Thursday, North Korea’s Foreign Ministry issued a statement denying again that Mr. Warmbier had been tortured and accusing the United States of “employing even a dead person” in a “conspiracy campaign” against North Korea. Dr. Sammarco’s examination, which was concluded earlier this month, did not find signs of torture but could not rule out the possibility. “There are a lot of horrible things you can do to a human body that don’t leave external signs behind,” Dr. Sammarco said. © 2017 The New York Times Company

Keyword: Brain Injury/Concussion
Link ID: 24122 - Posted: 09.29.2017

Greta Jochem Concussions have gotten a lot of attention in recent years, especially as professional football players' brains have shown signs of degenerative brain disease linked with repeated blows to the head. Now, a new analysis confirms what many doctors fear — that concussions start showing up at a high rate in teens who are active in contact sports. About 20 percent of teens said they have been diagnosed with at least one concussion. And nearly 6 percent said they've been diagnosed with more than one, according to a research letter published Tuesday in the Journal of the American Medical Association. The Centers for Disease Control and Prevention says concussions can result in headaches, nausea and irritability. While most people do not suffer from long-term impacts from a concussion, between 10 percent and 20 percent may experience symptoms like depression, headaches or difficulty concentrating. Some people experience sleep problems, and multiple concussions are one way to cause chronic traumatic encephalopathy, a degenerative brain disease notably found in some NFL players. The letter's authors looked at 13,000 questionnaire responses from the 2016 version of Monitoring the Future. Each year since 1975, the study, run by the University of Michigan Survey Research Center, has surveyed high school students all over the country about their behaviors and attitudes. According to Philip Veliz, an author of the JAMA letter and an assistant research professor at the University of Michigan's Institute for Research on Women & Gender, in 2016, the survey added a question asking whether students had ever had a concussion. © 2017 npr

Keyword: Brain Injury/Concussion; Development of the Brain
Link ID: 24117 - Posted: 09.28.2017

By BENEDICT CAREY The brain damage was so severe that scientists all but gasped. Aaron Hernandez, the former New England Patriots tight end, was convicted of murder and killed himself in prison last April at age 27. An autopsy revealed that he had brain injuries akin to that seen in afflicted former players in their 60s, researchers announced on Thursday. The sheer extent of the damage turns on its head the usual question about violence and so-called chronic traumatic encephalopathy. If accumulated head trauma can cause such damage, might the injuries in turn lead to murder and suicide? It’s a natural presumption to make, given the tragic suicides of Junior Seau, Dave Duerson and other former football players diagnosed post-mortem with C.T.E. And it’s a question that the courts will have to wrestle with. On Friday, the National Football League vowed to defend itself against a lawsuit filed on behalf of Mr. Hernandez’s daughter and fiancée, who claims that his injuries and death were a direct result of his participation in football. The science itself — like most attempts to link brain biology to behavior — is murkier. In recent decades, researchers have made extraordinary strides in understanding the workings of brain cells, neural circuits and anatomy. Yet drawing a direct line from those basic findings to what people do out in the world is dicey, given the ineffable interplay between circumstance, relationships and personality. What scientists — from such diverse fields as psychiatry, neurology and substance use — can say is that the arrows seem to be pointing in the same direction. A number of brain states raise the risk of acting out violently, and the evidence so far, while incomplete, suggests that C.T.E. may be one of them. Dr. Samuel Gandy, director of the N.F.L. neurology program at Mount Sinai Medical Center, said that rage and irritability “are far and away the most prominent symptoms” among former players with likely C.T.E., in his research. His group has identified 10 of 24 former players who probably have C.T.E. © 2017 The New York Times Company

Keyword: Brain Injury/Concussion; Aggression
Link ID: 24104 - Posted: 09.23.2017

While immune cells called neutrophils are known to act as infantry in the body’s war on germs, a National Institutes of Health-funded study suggests they can act as medics as well. By studying rodents, researchers showed that instead of attacking germs, some neutrophils may help heal the brain after an intracerebral hemorrhage, a form of stroke caused by ruptured blood vessels. The study suggests that two neutrophil-related proteins may play critical roles in protecting the brain from stroke-induced damage and could be used as treatments for intracerebral hemorrhage. “Intracerebral hemorrhage is a damaging and often fatal form of stroke for which there are no effective medicines,” said Jaroslaw Aronowski, M.D., Ph.D., professor, department of neurology, at the University of Texas Health Science Center at Houston, and senior author of the study published in Nature Communications. “Our results are a hopeful first step towards developing a treatment for this devastating form of stroke.” Accounting for 10 to 15 percent of all strokes, intracerebral hemorrhages happen when blood vessels rupture and leak blood into the brain, often leading to death or long-term disability. Chronic high blood pressure is the leading risk factor for these types of strokes. The initial phase of damage appears to be caused by the pressure of blood leaking into the brain. Over time, further damage may be caused by the accumulation of toxic levels of blood products, infiltrating immune cells, and swelling. Decades of research suggest that neutrophils are some of the earliest immune cells to respond to a hemorrhage, and that they may both harm and heal the brain.

Keyword: Stroke; Neuroimmunology
Link ID: 24090 - Posted: 09.21.2017

By Deborah Tuerkheimer Controversy surrounding “shaken baby syndrome” (SBS) is taking centre stage again. The American Academy of Pediatrics (AAP) meets today with a session underscoring the message that most paediatricians – child abuse specialists among them – say it remains a “valid” diagnosis. In other words, the paediatric community continues to believe that shaking can bring about one or more of the classic triad of neurological symptoms: bleeding beneath the outer layer of membranes surrounding the brain, bleeding in the retina, and brain swelling. This is likely to prompt vigorous opposition from those within the medical community who challenge the scientific underpinnings of SBS. It is also likely to resonate with the public, many of whom assume that this diagnosis alone amounts to proof beyond a reasonable doubt that a caregiver or parent injured or killed a baby by violent shaking. It does not. Yet for decades such prosecutions did rest on the testimony of medical experts regarding the triad. Doctors came to court and explained that vigorous shaking – not an accidental jostle or an effort to revive an unconscious child – was the only possible explanation for those symptoms. The triad was even used to identify a perpetrator – whoever was last with the lucid baby. SBS could, in essence, be a medical diagnosis of murder. Beginning in the 1990s, triad-only prosecutions became increasingly commonplace, sending many caregivers to prison. © Copyright New Scientist Ltd.=

Keyword: Brain Injury/Concussion; Development of the Brain
Link ID: 24082 - Posted: 09.20.2017

By Jessica Hamzelou People who are blind use parts of their brain that normally handle for vision to process language, as well as sounds – highlighting the brain’s extraordinary ability to requisition unused real estate for new functions. Neurons in the part of the brain normally responsible for vision synchronise their activity to the sounds of speech in blind people, says Olivier Collignon at the Catholic University of Louvain (UCL) in Belgium. “It’s a strong argument that the organisation of the language system… is not constrained by our genetic blueprint alone,” he says. The finding builds on previous research showing that the parts of the brain responsible for vision can learn to process other kinds of information, including touch and sound, in people who are blind. Collignon and his colleagues made the discovery using magnetoencephalography (MEG), which measures electrical activity in the brain. Read more: How some blind people are able to echolocate like bats While they were being scanned, groups of sighted and blind volunteers were played three clips from an audio book. One recording was clear and easy to understand; another was distorted but still intelligible; and the third was modified so as to be completely incomprehensible. Both groups showed activity in the brain’s auditory cortex, a region that processes sounds, while listening to the clips. But the volunteers who were blind showed activity in the visual cortex, too. © Copyright New Scientist Ltd.

Keyword: Vision; Language
Link ID: 24075 - Posted: 09.19.2017

By NATALIE ANGIER A normal human baby, according to psychologists, will cry about two hours over the course of a day. A notorious human crybaby, according to her older siblings, parents and the building superintendent, will cry for two hours every two hours, refusing to acknowledge any distinction between crying and other basic infant activities, like “being awake” or “breathing.” Current and former whine enthusiasts, take heart. It turns out that infant crying is not only as natural and justifiable as breathing: The two acts are physically, neurologically, primally intertwined. Scientists have discovered that the small cluster of brain cells in charge of fast, active respiration also grant a baby animal the power to cry. Reporting in the Proceedings of the National Academy of Sciences, Carmen Birchmeier and Luis Hernandez-Miranda, of the Max Delbruck Center for Molecular Medicine in Berlin, and their colleagues showed that infant mice stripped of this key node — a mere 17,000 neurons, located in the evolutionarily ancient hindbrain — can breathe slowly and passively, but not vigorously or animatedly. When they open their mouths to cry, nothing comes out. As a result, their mothers ignore them, and the poorly breathing pups quickly die. “This was an astonishing finding,” Dr. Birchmeier said. “The mother could see the pups and smell the pups, but if they didn’t vocalize, it was as though they didn’t exist.” The new study is just one in a series of recent reports that reveal the centrality of crying to infant survival, and how a baby’s bawl punches through a cluttered acoustic landscape to demand immediate adult attention. The sound of an infant’s cry arouses a far quicker and stronger response in action-oriented parts of the adult brain than do similarly loud or emotionally laden noises, like a dog barking or a neighbor weeping. © 2017 The New York Times Company

Keyword: Sexual Behavior; Animal Communication
Link ID: 24037 - Posted: 09.05.2017

By SANDY SMOLAN I’ve long been interested in the capacity of storytelling and journalism to transport an audience. Shooting my first documentary in North Africa 35 years ago, I used multiple projectors and screens to create an immersive experience. The approach at the time was experimental and while I moved on to more traditional storytelling in features, television and documentaries, I always held on to the idea of using immersive environments to transport viewers and allow them to experience an expanded vision of the world. They surrounded the divers and started clicking — they seemed to be saying hello. Then last year I visited the virtual reality lab at Stanford, which is at the fore of contemporary immersive journalism. I realized that V.R. had the potential to become a powerful new form of storytelling, and the medium has been evolving faster than anyone had ever expected. After I read James Nestor’s book “Deep,” about free diving and the human connection to the ocean, I realized that the combination of stunning imagery and the way in which a team of researchers were studying the language of whales and dolphins by free diving with them would translate perfectly to V.R. I had never forgotten my first open water dive in the Caribbean with my father when I was 17 and the transcendent experience of being suspended 30 feet beneath the surface, midway between the boat above us and the white sand of the ocean floor below. Now my son has become a free diver and as I recently watched him dive silently, on a single breath, his body elongated with outsize fins, unencumbered by tanks, regulators and the noise of escaping bubbles, I saw what James so eloquently described in his book — a human being interacting with the ocean and marine life in a manner few people can ever experience. © 2017 The New York Times Company

Keyword: Animal Communication; Hearing
Link ID: 24032 - Posted: 09.04.2017

By Brian Levine, Carrie Esopenko There are two ways to go about studying a disease. Let’s call them the retrospective and prospective methods. In the retrospective method, scientists identify individuals with the disease and ask about the circumstances that led to the illness. In the prospective method, they start with a representative sample of people and track them over time to see who develops the disease. Both methods have yielded important discoveries, but the retrospective method is much more prone to distortion than the prospective method. Consider the following example. Using the retrospective method, 100 percent of alcoholics drink alcohol. Yet drinking alcohol does not necessarily lead to alcoholism, as can be determined by the prospective method in which it can be seen that the proportion of those who enjoy alcoholic drinks and become alcoholics is less than 100 percent. Boston University’s Chronic Traumatic Encephalopathy (CTE) Center recently reported that 99 percent of NFL alumni who made brain donations at the time of death have CTE (a similar finding was reported in 2013). While researchers acknowledge that those who make brain donations are not representative of retired NFL players (much less those with sports-related concussions in general) it is remarkably easy to make the same mistake as in the alcoholism example—that is, making the assumption that this finding generalizes to the broader population of athletes exposed to concussion. © 2017 Scientific America

Keyword: Brain Injury/Concussion
Link ID: 24025 - Posted: 09.02.2017

By Andy Coghlan How and when did we first become able to speak? A new analysis of our DNA reveals key evolutionary changes that reshaped our faces and larynxes, and which may have set the stage for complex speech. The alterations were not major mutations in our genes. Instead, they were tweaks in the activity of existing genes that we shared with our immediate ancestors. These changes in gene activity seem to have given us flat faces, by retracting the protruding chins of our ape ancestors. They also resculpted the larynx and moved it further down in the throat, allowing our ancestors to make sounds with greater subtleties. The study offers an unprecedented glimpse into how our faces and vocal tracts were altered at the genetic level, paving the way for the sophisticated speech we take for granted. However, other anthropologists say changes in the brain were at least equally important. It is also possible that earlier ancestors could speak, but in a more crude way, and that the facial changes simply took things up a notch. Liran Carmel of the Hebrew University of Jerusalem and his colleagues examined DNA from two modern-day people and four humans who lived within the last 50,000 years. They also looked at extinct hominins: two Neanderthals and a Denisovan. Finally, they looked at genetic material from six chimpanzees and data from public databases supplied by living people. © Copyright New Scientist Ltd.

Keyword: Language; Evolution
Link ID: 24004 - Posted: 08.28.2017

Jon Hamilton It's not just what you say that matters. It's how you say it. Take the phrase, "Here's Johnny." When Ed McMahon used it to introduce Johnny Carson on The Tonight Show, the words were an enthusiastic greeting. But in The Shining, Jack Nicholson used the same two words to convey murderous intent. Now scientists are reporting in the journal Science that they have identified specialized brain cells that help us understand what a speaker really means. These cells do this by keeping track of changes in the pitch of the voice. "We found that there were groups of neurons that were specialized and dedicated just for the processing of pitch," says Dr. Eddie Chang, a professor of neurological surgery at the University of California, San Francisco. Chang says these neurons allow the brain to detect "the melody of speech," or intonation, while other specialized brain cells identify vowels and consonants. "Intonation is about how we say things," Chang says. "It's important because we can change the meaning, even — without actually changing the words themselves." For example, by raising the pitch of our voice at the end of a sentence, a statement can become a question. The identification of neurons that detect changes in pitch was largely the work of Claire Tang, a graduate student in Chang's lab and the Science paper's lead author. Tang and a team of researchers studied the brains of 10 epilepsy patients awaiting surgery. The patients had electrodes placed temporarily on the surface of their brains to help surgeons identify the source of their seizures. © 2017 npr

Keyword: Language
Link ID: 23996 - Posted: 08.25.2017

By Sameer Deshpande, Raiden Hasegawa, Christina Master, Amanda Rabinowitz, Dylan Small American football is the largest participation sport in U.S. high schools. Recently, many have expressed concern about the sport’s safety with some even calling for banning youth and high school tackle football. We recently published a study in JAMA Neurology suggesting that, in general, men who played high school football in 1950s Wisconsin did not have a higher risk of poor cognitive or emotional health later in life than those who did not play. Recent concerns about football’s safety have been driven largely by reports of chronic traumatic encephalopathy (CTE) among retired professional players. CTE is a neurodegenerative disease thought to result from repetitive head trauma with symptoms including memory loss, aggression, confusion and depression. A recent study in JAMA reported evidence of CTE in 110 of 111 deceased retired NFL players who donated their brains for posthumous examination. This important study adds to a larger body of work linking repetitive sports-related concussion with neurodegenerative disease. However, such research, which depends on brains donated by families of players many of whom were symptomatic before death, is not designed to establish the base rate of neurodegeneration among the larger population of football players. A critical question remains: what is the risk of later-life cognitive and emotional dysfunction for American high school football players? © 2017 Scientific American

Keyword: Brain Injury/Concussion; Development of the Brain
Link ID: 23994 - Posted: 08.25.2017

By Jessica Hamzelou People who use methamphetamine are almost five times more likely to have a stroke caused by a bleed in the brain, many of which are fatal. “We can add stroke to the list of terrible and devastating things that methamphetamine does,” says Damian Zuloaga, of the University at Albany, New York. Beyond the signature tooth decay known as “meth mouth”, methamphetamine also increases heart rate and blood pressure, and can trigger heart attacks. The drug can lead to psychosis, and has been linked to anxiety disorders, depression, and problems with movement similar to those seen in Parkinson’s disease. A handful of studies have also linked methamphetamine use to strokes. To explore further, Julia Lappin and her colleagues at the Australian National Drug and Alcohol Research Centre in Sydney sifted through published research on the topic. The team specifically looked for research into people under the age of 45 – a group less likely to be affected by age-related causes of stroke. They assessed the results of 77 studies in total. Most of these studies were conducted in the US, where, in 2012, around 1.2 million people reported using methamphetamine in the past year. Several of the studies the team looked at reported that strokes are responsible for between one and five per cent of methamphetamine-related deaths. And other studies found that methamphetamine was to blame for between two and six per cent of all strokes caused by a blockage in the brain’s blood flow in under 45s. © Copyright New Scientist Ltd.

Keyword: Drug Abuse; Stroke
Link ID: 23988 - Posted: 08.24.2017