Chapter 15. Language and Our Divided Brain
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Tom Bawden The mystery behind the nightingale’s beautiful song has been revealed, with scientists finding that male birds sing complex notes to prove to females that they would be a good father to their children. Nightingales use their songs to advertise their family values, according to new research which discovers that the better the singer, the more support they are likely to offer their young family by feeding and defending them from predators. But while the beauty comes from the complexity of the song, the effect it has on the females is based on something far more mundane – the amount of effort the singer has put into his performance. Researchers at the Freie Universitat Berlin found that complicated choral arrangements are much harder to sing, especially when they include frequent appearances of long buzzing sounds and require the bird to be in good physical condition. “We don’t think the female is concerned with the beauty of the song but rather the information encoded in the song that tells her about the singer’s characteristics – his age, where he was raised, the strength of his immune system and how motivated he is to contribute to bringing up the young,” Professor Silke Kipper, one of the report’s authors, told The Independent. “The songs can also be a good indication of the bird’s ability to learn, which is another important characteristic of a good parent.” © independent.co.uk
by Meghan Rosen When we brought Baby S home from the hospital six months ago, his big sister, B, was instantly smitten. She leaned her curly head over his car seat, tickled his toes and cooed like a pro — in a voice squeakier than Mickey Mouse’s. B’s voice — already a happy toddler squeal — sounded as if she'd sucked in some helium. My husband and I wondered about her higher pitch. Are humans hardwired to chitchat squeakily to babies, or did B pick up vocal cues from us? (I don’t sound like that, do I?) If I’m like other mothers, I probably do. American English-speaking moms dial up their pitch drastically when talking to their children. But dads’ voices tend to stay steady, researchers reported May 19 in Pittsburgh at the 169th Meeting of the Acoustical Society of America. “Dads talk to kids like they talk to adults,” says study coauthor Mark VanDam, a speech scientist at Washington State University. But that doesn’t mean fathers are doing anything wrong, he says. Rather, they may be doing something right: offering their kids a kind of conversational bridge to the outside world. Scientists have studied infant- or child-directed speech (often called “motherese” or “parentese”) for decades. In American English, this type of babytalk typically uses high pitch, short utterances, repetition, loud volume and slowed-down speech. Mothers who speak German Japanese, French, and other languages also tweak their pitch and pace when talking to children. But no one had really studied dads, VanDam says. © Society for Science & the Public 2000 - 2015.
The virtual reality arm appears to move faster and more accurately than the real arm Virtual reality could help stroke patients recover by "tricking" them into thinking their affected limb is more accurate than it really is. Researchers in Spain found that making the affected limb appear more effective on screen increased the chance the patient would use it in real life. This is important because stroke victims often underuse their affected limbs, making them even weaker. A stroke charity welcomed the study and called for more research. In the study of 20 stroke patients, researchers sometimes enhanced the virtual representation of the patient's affected limb, making it seem faster and more accurate, but without the patient's knowledge. After the episodes in which the limbs were made to seem more effective, the patients then went on to use them more, according to lead researcher Belen Rubio. "Surprisingly, only 10 minutes of enhancement was enough to induce significant changes in the amount of spontaneous use of the affected limb," said Mrs Rubio from the Laboratory of Synthetic, Perceptive, Emotive and Cognitive Systems at Pompeu Fabra University in Spain. "This therapy could create a virtuous circle of recovery, in which positive feedback, spontaneous arm use and motor performance can reinforce each other. Engaging patients in this ongoing cycle of spontaneous arm use, training and learning could produce a remarkable impact on their recovery process," she said. © 2015 BBC
Link ID: 21030 - Posted: 06.09.2015
By Lisa Sanders On Thursday, we challenged Well readers to figure out why a previously healthy 31-year-old woman suddenly began having strokes. I thought this was a particularly tough case – all the more so since I had never heard of the disease she was ultimately diagnosed with. Apparently I was not alone. Only a few dozen of the 400 plus readers who wrote in were able to make this difficult diagnosis. The correct diagnosis is: Susac’s syndrome The first person to identify this rare neurological disorder was Errol Levine, a retired radiologist from South Africa, now living in Santa Fe, N.M. The location of the stroke shown — in a part of the brain known as the corpus callosum — was a subtle clue, and Dr. Levine recalled reading of an autoimmune disease characterized by strokes in this unusual area of the brain. This is Dr. Levine’s second win. Well done, sir! Susac’s syndrome is a rare disorder first described in 1979 by Dr. John Susac, a neurologist in Winter Haven, Fla. Dr. Susac described two women, one 26 years old, the other 40, who he encountered within weeks of one another. Both had the same unusual triad of psychiatric symptoms suggestive of some type of brain inflammation, hearing loss, and patchy vision loss caused by blockages of the tiniest vessels of the retina known as branch retinal arteries. A few years later, Dr. Susac encountered two more cases and presented one of these at a meeting as a mystery diagnosis. The doctor who figured it out called the disorder Susac’s syndrome, and the name stuck. Seen primarily in young women, Susac’s is thought to be an autoimmune disorder in which antibodies, the foot soldiers of the immune system, mistakenly attack tissues in some of the smallest arteries in the brain. The inflammation of these small vessels blocks the flow of blood, causing tiny strokes. © 2015 The New York Times Company
by Clare Wilson A new study has discredited the theory that dyslexia is caused by visual problems. So what does cause the condition and how can it be treated? What kind of visual problems are claimed to cause dyslexia? A huge variety. They include difficulties in merging information from both eyes, problems with glare from white pages or the text blurring or "dancing" on the page. A host of products claim to relieve this so-called visual stress, especially products that change the background colour of the page, such as tinted glasses and coloured overlays. Others advise eye exercises that supposedly help people with dyslexia track words on the page. Despite lack of evidence that these approaches work, some people with dyslexia say they help – more than half of university students with dyslexia have used such products. What are the new findings? That there's no evidence visual stress is linked with dyslexia. Nearly 6000 UK children aged between 7 and 9 had their reading abilities tested as well as performing a battery of visual tests. About 3 per cent of them had serious dyslexia, in line with the national average. But in the visual tests, the differences between the students with and without dyslexia were minimal. In two of the 11 tests, about 16 per cent of the children with dyslexia scored poorly, compared with 10 per cent for children with normal reading abilities. But that small difference could be caused by the fact that they read less, says author Alexandra Creavin of the University of Bristol, UK. And more importantly, the 16 per cent figure is so low, it can't be the main explanation for dyslexia. © Copyright Reed Business Information Ltd.
By Jason G. Goldman In 1970 child welfare authorities in Los Angeles discovered that a 14-year-old girl referred to as “Genie” had been living in nearly total social isolation from birth. An unfortunate participant in an unintended experiment, Genie proved interesting to psychologists and linguists, who wondered whether she could still acquire language despite her lack of exposure to it. Genie did help researchers better define the critical period for learning speech—she quickly acquired a vocabulary but did not gain proficiency with grammar—but thankfully, that kind of case study comes along rarely. So scientists have turned to surrogates for isolation experiments. The approach is used extensively with parrots, songbirds and hummingbirds, which, like us, learn how to verbally communicate over time; those abilities are not innate. Studying most vocal-learning mammals—for example, elephants, whales, sea lions—is not practical, so Tel Aviv University zoologists Yosef Prat, Mor Taub and Yossi Yovel turned to the Egyptian fruit bat, a vocal-learning species that babbles before mastering communication, as a child does. The results of their study, the first to raise bats in a vocal vacuum, were published this spring in the journal Science Advances. Five bat pups were reared by their respective mothers in isolation, so the pups heard no adult conversations. After weaning, the juveniles were grouped together and exposed to adult bat chatter through a speaker. A second group of five bats was raised in a colony, hearing their species' vocal interactions from birth. Whereas the group-raised bats eventually swapped early babbling for adult communication, the isolated bats stuck with their immature vocalizations well into adolescence. © 2015 Scientific American
By Meeri Kim The dangers of concussions, caused by traumatic stretching and damage to nerve cells in the brain that lead to dizziness, nausea and headache, has been well documented. But ear damage that is sometimes caused by a head injury has symptoms so similar to the signs of a concussion that doctors may misdiagnose it and administer the wrong treatment. A perilymph fistula is a tear or defect in the small, thin membranes that normally separate the air-filled middle ear from the inner ear, which is filled with a fluid called perilymph. When a fistula forms, tiny amounts of this fluid leak out of the inner ear, an organ crucial not only for hearing but also for balance. Losing even a few small drops of perilymph leaves people disoriented, nauseous and often with a splitting headache, vertigo and memory loss. While most people with a concussion recover within a few days, a perilymph fistula can leave a person disabled for months. There is some controversy around perilymph fistula due to its difficulty of diagnosis — the leak is not directly observable, but rather identified by its symptoms. However, it is generally accepted as a real condition by otolaryngologists and sports physicians, and typically known to follow a traumatic event. But concussions — as well as post-concussion syndrome, which is marked by dizziness, headache and other symptoms that can last even a year after the initial blow — also occur as the result of such an injury.
Athletes who lose consciousness after concussions may be at greater risk for memory loss later in life, a small study of retired National Football League players suggests. Researchers compared memory tests and brain scans for former NFL players and a control group of people who didn't play college or pro football. After concussions that resulted in lost consciousness, the football players were more likely to have mild cognitive impairment and brain atrophy years later. "Our results do suggest that players with a history of concussion with a loss of consciousness may be at greater risk for cognitive problems later in life," senior study author Munro Cullum, chief of neuropsychology at the University of Texas Southwestern Medical Center in Dallas, said by email. "We are at the early stages of understanding who is actually at risk at the individual level." Cullum and colleagues recruited 28 retired NFL players living in Texas: eight who were diagnosed with mild cognitive impairment and 20 who didn't appear to have any memory problems. They ranged in age from 36 to 79, and were an average of about 58 years old. All but three former athletes experienced at least one concussion, and they typically had more than three. Researchers compared these men to 27 people who didn't play football but were similar in age, education, and mental capacity to the retired athletes, including six with cognitive impairment. These men were 41 to 77 years old, and about 59 on average. ©2015 CBC/Radio-Canada
by Bas den Hond Watch your language. Words mean different things to different people – so the brainwaves they provoke could be a way to identify you. Blair Armstrong of the Basque Center on Cognition, Brain, and Language in Spain and his team recorded the brain signals of 45 volunteers as they read a list of 75 acronyms – such as FBI or DVD – then used computer programs to spot differences between individuals. The participants' responses varied enough that the programs could identify the volunteers with about 94 per cent accuracy when the experiment was repeated. The results hint that such brainwaves could be a way for security systems to verify individuals' identity. While the 94 per cent accuracy seen in this experiment would not be secure enough to guard, for example, a room or computer full of secrets, Armstrong says it's a promising start. Techniques for identifying people based on the electrical signals in their brain have been developed before. A desirable advantage of such techniques is that they could be used to verify someone's identity continuously, whereas passwords or fingerprints only provide a tool for one-off identification. Continuous verification – by face or ear recognition, or perhaps by monitoring brain activity – could in theory allow someone to interact with many computer systems simultaneously, or even with a variety of intelligent objects, without having to repeatedly enter passwords for each device. © Copyright Reed Business Information Ltd
By Virginia Morell Like humans, dolphins, and a few other animals, North Atlantic right whales (Eubalaena glacialis) have distinctive voices. The usually docile cetaceans utter about half a dozen different calls, but the way in which each one does so is unique. To find out just how unique, researchers from Syracuse University in New York analyzed the “upcalls” of 13 whales whose vocalizations had been collected from suction cup sensors attached to their backs. An upcall is a contact vocalization that lasts about 1 to 2 seconds and rises in frequency, sounding somewhat like a deep-throated cow’s moo. Researchers think the whales use the calls to announce themselves and to “touch base” with others of their kind, they explained in a poster presented today at the Meeting of the Acoustical Society of America in Pittsburgh, Pennsylvania. After analyzing the duration and harmonic frequency of these upcalls, as well as the rate at which the frequencies changed, the scientists found that they could distinguish the voices of each of the 13 whales. They think their discovery will provide a new tool for tracking and monitoring the critically endangered whales, which number about 450 and range primarily from Florida to Newfoundland. © 2015 American Association for the Advancement of Science.
Haroon Siddique Long-term depression in people over 50 could more than double their risk of suffering a stroke, with the risk remaining significantly higher even after the depression allays, research suggests. The US study of more than 16,000 people, which documented 1,192 strokes, found that onset of recent depression was not associated with higher stroke risk, suggesting the damage is done by depressive symptoms accumulating over time. The study’s lead author, Paola Gilsanz, from Harvard University’s TH Chan School of Public Health, said: “Our findings suggest that depression may increase stroke risk over the long term. Looking at how changes in depressive symptoms over time may be associated with strokes allowed us to see if the risk of stroke increases after elevated depressive symptoms start or if risk goes away when depressive symptoms do. We were surprised that changes in depressive symptoms seem to take more than two years to protect against or elevate stroke risk.” The research, published on Wednesday in the Journal of the American Heart Association, used data from between 1998 and 2010 from the Health and Retirement Study, which interviews a panel of representative Americans aged over 50 every two years, on their depressive symptoms, history of stroke, and stroke risk factors. Gilsanz, with colleagues from universities in Washington, California and Minnesota, and Bronx Partners for Healthy Communities, found that people with high depressive symptoms at two consecutive interviews had a 114% higher risk of suffering a first stroke, compared with people without depression at either interview. Those who had depressive symptoms at one interview but not at the next had a 66% higher risk. © 2015 Guardian News and Media Limited
By Smitha Mundasad Health reporter There has been a worrying rise in the number of working-age men and women having strokes, a charity has warned. In England in 2014 there were 6,221 hospital admissions for men aged 40-54 - a rise of 1,961 on 14 years earlier, a Stroke Association study shows. Experts said unhealthy lifestyles were partly to blame for the rise, though the growing population and changes to hospital practice also played a part. Overall the rate of strokes is going down in the UK, however. Researchers say based on their findings strokes should not be considered as a disease of the old. Strokes are caused by blood clots or bleeds to the brain and can lead to long-lasting disability. The majority occur in people aged over 65, and though rates are decreasing in this group, this report suggests growing numbers of younger people are at risk. Experts analysed national hospital admission data spanning 2000 to 2014. Trends for people in their 40s and early 50s appeared to be getting worse. In women aged 40-54, there were an extra 1,075 strokes recorded in 2014, compared with 2000. Experts said growing obesity levels, sedentary lives and unhealthy diets - which raise the risks of dangerous blood clots - all played a part. And they argued strokes among this age group had long-lasting personal and financial impacts on individuals and their families, as well as on the economy. Recovering patients can find it difficult to return to work and should have more support from employers, the report suggests. Jon Barrick, of the Stroke Association, said: "These figures show stroke can no longer be seen as a disease of older people. "There is an alarming increase in the numbers of people having a stroke in working age. © 2015 BBC.
Link ID: 20912 - Posted: 05.12.2015
by Jessica Hamzelou GOO, bah, waahhhh! Crying is an obvious sign something is up with your little darling but beyond that, their feelings are tricky to interpret – except at playtime. Trying to decipher the meaning behind the various cries, squeaks and babbles a baby utters will have consumed many a parent. Some researchers reckon babies are simply practising to learn to speak, while others think these noises have some underlying meaning. "Babies probably aren't aware of wanting to tell us something," says Jitka Lindová, an evolutionary psychologist at Charles University in Prague, Czech Republic. Instead, she says, infants are conveying their emotions. But can adults pick up on what those emotions are? Lindová and her colleagues put 333 adults to the test. First they made 20-second recordings of five- to 10-month-old babies while they were experiencing a range of emotions. For example, noises that meant a baby was experiencing pain were recorded while they received their standard vaccinations. The team also collected recordings when infants were hungry, separated from a parent, reunited, just fed, and while they were playing. The volunteers had to listen to a selection of the recordings then guess which situation each related to. The adults could almost always tell whether a baby was distressed in some way. This makes sense – a baby's survival may depend on an adult being able to tell whether a baby is unwell, in pain or in danger. © Copyright Reed Business Information Ltd.
By HOWARD MEGDAL Ali Krieger has a lot on her plate this year. As a defender for the United States women’s national team, she is weeks away from the start of her second World Cup. And as one of the most prominent members of the National Women’s Soccer League, she is helping build an audience for her team and the fledgling league. On April 10, though, those roles were jeopardized when Krieger, playing for the Washington Spirit in an N.W.S.L. game at Houston, sustained a concussion after rising for a header. “Right when it happened, I had no idea why I was lying on the ground and why people were standing over me,” Krieger said by telephone last week. “And people were talking to me — I couldn’t really open my eyes at first. I was like, ‘Is this a dream?’ ” Krieger said that she lost consciousness before hitting the ground and that when she woke up, even as she lay on the grass, she quickly tried to diagnose the injury. Krieger said she believed the concussion was minor — certainly less serious than one she sustained in 2013 that took her a couple of months to recover from. But injuries like hers and the ones sustained by several other players in high-profile cases have troubled concussion activists. They say that despite clear progress in the recognition and treatment of head injuries in soccer, it is often up to the injured athlete or that athlete’s coach to determine when an injury requires removal from play. In the worst cases, the time remaining in a match and the score play a role in the decision. The ESPN analyst Taylor Twellman, a former striker whose playing career was ended by head injuries, has been a vocal advocate on television and social media for better treatment of head injuries. But given the pressure to succeed at the game’s top levels, he said in an email, “I’m scared of what I still hear in 2015.” © 2015 The New York Times Company
Keyword: Brain Injury/Concussion
Link ID: 20876 - Posted: 05.04.2015
// by Jennifer Viegas Male species of a West African monkey communicate using at least these six main sounds: boom-boom, krak, krak-oo, hok, hok-oo and wak-oo. Key to the communication by the male Campbell's monkey is the suffix "oo," according to a new study, which is published in the latest issue of the Proceedings of the Royal Society B. By adding that sound to the end of their calls, the male monkeys have created a surprisingly rich "vocabulary" that males and females of their own kind, as well as a related species of monkey, understand. The study confirms prior suspected translations of the calls. For example, "krak" means leopard, while "krak-oo" refers to other non-leopard threats, such as falling branches. "Boom-boom-krak-oo" can roughly translate to, "Watch out for that falling tree branch." "Several aspects of communication in Campbell's monkeys allow us to draw parallels with human language," lead author Camille Coye, a researcher at the University of St. Andrews, told Discovery News. For the study, she and her team broadcast actual and artificially modified male Campbell's monkey calls to 42 male and female members of a related species: Diana monkeys. The latter's vocal responses showed that they understood the calls and replied in predicted ways. They freaked out after hearing "krak," for example, and remained on alert as they do after seeing a leopard. © 2015 Discovery Communications, LLC.
By Sid Perkins Imagine having a different accent from someone else simply because your house was farther up the same hill. For at least one species of songbird, that appears to be the case. Researchers have found that the mating songs of male mountain chickadees (Poecile gambeli, shown) differ in their duration, loudness, and the frequency ranges of individual chirps, depending in part on the elevation of their habitat in the Sierra Nevada mountains of the western United States. The songs also differed from those at similar elevations on a nearby peak. Young males of this species learn their breeding songs by listening to adult males during their first year of life, the researchers note. And because these birds don’t migrate as the seasons change, and young birds don’t settle far from where they grew up, it’s likely that the differences persist in each local group—the ornithological equivalent of having Southern drawls and Boston accents. Females may use the differences in dialect to distinguish local males from outsiders that may not be as well adapted to the neighborhood they’re trying to invade, the team reports today in Royal Society Open Science. © 2015 American Association for the Advancement of Science
By Linda Carroll Women may have a harder time recovering from concussion, a new study suggests. Taiwanese researchers found women were more likely than men to continue to have memory deficits nearly three months after a mild traumatic brain injury, or mTBI, according to the study published in the journal Radiology. The findings provide "evidence that women may have greater risk for developing working memory impairment after mTBI and may have longer recovery time," said study coauthor Dr. Chi-Jen Chen, a professor at Taipei Medical University Shuang-Ho Hospital. "According to our preliminary results, more aggressive management should be initiated once mTBI is diagnosed in women, including close monitoring of symptoms, more aggressive pharmacological treatments, rehabilitation, as well as longer follow-up." Chen had noticed that almost twice as many women as men were showing up in her clinic after concussions. She wondered if there might be some kind of physical difference making concussions more severe in women. To determine whether there was a real effect, she and her colleagues rounded up 30 concussed patients and 30 non-brain-injured volunteers. Each group had equal numbers of men and women. The concussed patients were scanned shortly after doing a memory test with functional MRI twice: one month after their injury and again six weeks later. The volunteers were scanned once. All the study participants took neuropsychological tests designed to measure attention span, impulsivity, and deficits in working memory.
By KEN BELSON A federal district court judge on Wednesday gave her final approval to the settlement of a lawsuit brought by more than 5,000 former players who accused the N.F.L. of hiding from them the dangers of concussions, a major step toward ending one of the most contentious legal battles in league history. The settlement provides payments of up to $5 million to players who have one of a handful of severe neurological disorders, medical monitoring for all players to determine if they qualify for a payment and $10 million for education about concussions. The landmark deal, which many players criticized, was originally reached in August 2013, but Judge Anita B. Brody twice asked the two sides to revise their agreement, first to uncap the total amount of damages that could be paid for the conditions covered, and then to remove the limit on how much could be spent on medical monitoring. As part of the deal, the N.F.L. insisted that all retired players — not just the 5,000 or so who sued the league — be covered by the settlement as a way to fend off lawsuits in the future. But about 200 players, including Junior Seau, who committed suicide and was later found to have a degenerative brain disease, opted out of the settlement to preserve their right to continue fighting the league. Critics of the settlement said that even after the revisions, the number and variety of diseases covered by the deal were too small and that many players would receive only a small fraction of the multimillion-dollar payouts promised by the league after their age and years in the N.F.L. were considered. Critics also contended that the settlement needed to acknowledge more classes of plaintiffs, not only those with diagnosable diseases and those without them. © 2015 The New York Times Company
Keyword: Brain Injury/Concussion
Link ID: 20837 - Posted: 04.23.2015
by Clare Wilson I WAS prepared for the blood but the most shocking thing about watching brain surgery was seeing the surgical drapes being stapled to the patient's face. But surgeon Peter Hutchinson dismisses my concern that the tiny holes might bother the patient when she wakes up: "That's nothing compared with the massive hole we're about to make in her head." I am at Addenbrooke's Hospital in Cambridge, UK, to learn about craniectomy, a procedure that involves removing a large part of someone's skull, to relieve the pressure inside. There are no official tallies but it's thought that several hundred surgeries take place in the UK every year on people with head injuries or who have had a stroke. Once the brain is given room to swell, the pressure drops and the scalp is sewn back into place. The skull fragment can be stored in a freezer or kept sterile inside the patient's abdomen for weeks or months before it is reattached. The operation I'm witnessing is part of a randomised trial to compare the effectiveness of craniectomy with that of drugs alone to bring the pressure down. It will involve 400 people with head injuries, half of whom will get the surgery. This is needed as craniectomy has a long and chequered history. Human remains suggest it was done with stone tools in Peru a thousand years ago, a practise known as trepanning, perhaps for similar reasons as today. As a modern surgical procedure, though, it has fallen in and out of favour over the last few decades. Whether you would be sent for surgery today depends on how safe your surgeon thinks it is. © Copyright Reed Business Information Ltd.
Keyword: Brain Injury/Concussion
Link ID: 20836 - Posted: 04.23.2015
|By Rebecca Harrington It's best to treat the good with the bad, new medical insights into brain attacks suggest. Doctors are beginning to think the side of the brain opposite to a clot in stroke patients is just as important a target for treatment as the damaged tissue when it comes to a faster recovery. Only in the past few years have researchers discovered that the uninjured side of the brain becomes more active after a stroke to help its fallen neighbor. In some instances, it pumps out proteins that induce damaged neurons to begin repairs and others that trigger new blood vessels to form. It can even extend its own neurons across hemispheres to restore function. Current stroke treatments largely target the damaged tissue. “I think everyone thought, ‘The other side of the brain is working pretty well,’” says Stanford University neurologist Gary Steinberg. “‘Why don't we leave that alone?’” In light of the growing evidence that the healthy hemisphere provides aid naturally, however, doctors are now investigating how to boost its healing actions. One such drug, shepherded by Adviye Ergul of Georgia Regents University and Susan Fagan of the University of Georgia, activates receptors on uninjured tissue that trigger pathways to reduce harmful inflammation and support the growth of neurons and blood vessels on the side of the brain with the clot. The drug increases repair rates in rats that have experienced stroke—results described recently in the Journal of Hypertension—and Ergul and Fagan say the therapy could become available to humans in the next five years. © 2015 Scientific American
Link ID: 20835 - Posted: 04.23.2015