Links for Keyword: Laterality

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By Julie Hecht I’m right handed. Utensils, pens, pencils, and of course my toothbrush are all operated by my right hand. Like roughly 90% of people, my left hand simply isn’t cut out for much on its own. Dogs, outfitted with paws not hands, also appear to prefer one paw over the other. In dogs, paw laterality — or paw preference — is explored not with forks or pencils, but with more dog-appropriate motor tasks. Studies have asked which paw dogs use to reach toward food or which paw they use to remove something from their body, like a blanket. Researchers have even checked which paw dogs first lift to walk down a step and which paw they “give” when asked to “give” paw. To date, it has been assumed that, like us, dogs have a “hand” preference. But Deborah Wells, a longtime laterality researcher, wondered if something was missing. Studies of paw preference typically use only one test to investigate paw preference. As a result, it is unclear whether “dogs harbour consistent paw preferences” or, on the other hand (ha!), whether paw preference instead might be task-specific. Maybe a dog consistently reaches for food with the right paw, but is more likely to lift the left front paw to walk down a step. Wells and colleagues at the Animal Behaviour Center, Queen’s University, Belfast, took the natural next step (ha again!). They tested 32 pet dogs on four different paw preference tests to see whether dog paw preference was consistent across tests. To check preferences over time, a subset was tested 6 months later. This research was recently published in Behavioural Processes. © 2018 Scientific American

Related chapters from BN8e: Chapter 19: Language and Lateralization
Related chapters from MM:Chapter 15: Brain Asymmetry, Spatial Cognition, and Language
Link ID: 24837 - Posted: 04.09.2018

Laurel Hamers AUSTIN, Texas — Babies’ stroke-damaged brains can pull a mirror trick to recover. A stroke on the left side of the brain often damages important language-processing areas. But people who have this stroke just before or after birth recover their language abilities in the mirror image spot on the right side, a study of teens and young adults shows. Those patients all had normal language skills, even though as much as half of their brain had withered away, researchers reported February 17 at the annual meeting of the American Association for the Advancement of Science. Researchers so far have recruited 12 people ages 12 to 25 who had each experienced a stroke to the same region of their brain’s left hemisphere just before or after birth. People who have this type of stroke as adults often lose their ability to use and understand language, said study coauthor Elissa Newport, a neurology researcher at Georgetown University Medical Center in Washington, D.C. MRI scans of healthy siblings of the stroke patients showed activity in language centers in the left hemisphere of the brain when the participants heard speech. The stroke patients showed activity in the exact same areas — just on the opposite side of the brain. It’s well established that if an area of the brain gets damaged, other brain areas will sometimes compensate. But the new finding suggests that while young brains have an extraordinary capacity to recover, there might be limits on which areas can pinch-hit. |© Society for Science & the Public 2000 - 2018.

Related chapters from BN8e: Chapter 7: Life-Span Development of the Brain and Behavior; Chapter 19: Language and Lateralization
Related chapters from MM:Chapter 13: Memory, Learning, and Development; Chapter 15: Brain Asymmetry, Spatial Cognition, and Language
Link ID: 24678 - Posted: 02.19.2018

Menaka Wilhelm Karen Byrne's left hand sometimes operates on its own terms. It has unbuttoned shirts and stubbed out cigarettes, without her permission. Oh, and a few times, her own hand has slapped her across the face. This is a documented medical occurrence, not a premise for a Jim Carrey movie. The condition's name? Alien hand syndrome. Invisibilia featured Byrne and her alien hand last summer, and Giant Ant Studios recently created an otherworldly animation of Byrne's story. Byrne says she's gotten used to her left hand's new attitude, but alien hand syndrome is a pesky, strange condition. Imagine, as another patient has reported, sitting down to play the piano, only to have one hand levitate far above the piano keys as you try to practice. It's not that you've changed your mind; your goal is still to play a sonata. But that hand — still yours, and now also not yours — is obeying new directions, and you didn't come up with them consciously. For the pianist and Byrne, and many other cases, alien hand symptoms appears rooted in disruption of communication through the corpus callosum. That's the set of fibers that connects the right and left sides of the brain. The pianist's corpus callosum showed missing connections on an MRI, and Byrne's left hand developed its disobedience after a surgeon severed her corpus callosum in an operation to treat epileptic seizures. © 2018 npr

Related chapters from BN8e: Chapter 18: Attention and Higher Cognition; Chapter 19: Language and Lateralization
Related chapters from MM:Chapter 14: Attention and Consciousness; Chapter 15: Brain Asymmetry, Spatial Cognition, and Language
Link ID: 24643 - Posted: 02.10.2018

Nicola Davis Whether stalking down the stairs or tiptoeing into the litter box, cats have a preference for which paw they put forward, according to new research, with females favouring their right paw and males their left. Scientists say that while such preferences are a matter of individual inclination, males generally prefer stepping out with their left foot, while females typically favour their right. The team say understanding paw preference could offer insights into an animal’s vulnerability to stress. “Left-limbed animals, which rely more heavily on their right hemisphere for processing information, tend to show stronger fear responses, aggressive outbursts, and cope more poorly with stressful situations than animals that are right-limbed and rely more heavily on their left hemisphere for processing,” said Dr Deborah Wells, co-author of the research from Queen’s University, Belfast, adding that the right hemisphere is more responsible for processing of negative emotions. The study was conducted in owners’ homes and focused on spontaneous behaviour. In total, the team analysed data from 44 cats, 20 of which were female, collected by owners tracking which paw their cat used for taking the first step down stairs and stepping into the litter box, and which side their feline preferred to recline on. Over the course of three months owners recorded 50 instances of each behaviour. © 2018 Guardian News and Media Limited

Related chapters from BN8e: Chapter 19: Language and Lateralization; Chapter 12: Sex: Evolutionary, Hormonal, and Neural Bases
Related chapters from MM:Chapter 15: Brain Asymmetry, Spatial Cognition, and Language; Chapter 8: Hormones and Sex
Link ID: 24553 - Posted: 01.23.2018

By Katarina Zimmer Human mothers will usually cradle their infants on their left sides, such that they can gaze into each other’s left eyes, a position thought to favor processing in the brain’s right hemisphere. A new study in Biology Letters today (January 10) shows that walruses and flying foxes are no different, having such lateralized cuddling biases during maternal care, too. “Several decades ago, it was a popular belief that [this] brain asymmetry is only a human thing,” says the lead author of the study, Andrey Giljov, a zoologist at St. Petersburg University. But recent research has shown that in addition to humans, primate mothers tend to hold their infants to the left, and some of Giljov’s previous work demonstrated that several species of mammal infants like to keep their mothers in their left visual fields when approaching their parents from behind. A bias towards keeping a social partner on a certain side, the new study explains, reflects specialization of the brain’s right hemisphere for processing social information, as visual information is handled by an animal’s contralateral brain hemisphere. The work reveals that flying foxes and walruses not only have a left-biased cuddling preference, but also tend to rest face-to-face in the position that allows mother and young to keep each other within their left visual fields. © 1986-2018 The Scientist

Related chapters from BN8e: Chapter 19: Language and Lateralization; Chapter 12: Sex: Evolutionary, Hormonal, and Neural Bases
Related chapters from MM:Chapter 15: Brain Asymmetry, Spatial Cognition, and Language; Chapter 8: Hormones and Sex
Link ID: 24524 - Posted: 01.12.2018

By Abigail Zuger, M.D. All human beings contain a frightening tangle of primal impulses struggling for dominance, and that’s true not only for the chaotic psyche, but also the sober, dependable, symmetric old hands. Even the ordinary act of reaching for a fork or throwing a ball is the product of immensely complex genetic and neurologic negotiation. In some ways we are not that much further along than we were when our ancestors linked left-handedness to the sinister and the gauche. For all its sophistication, modern science is still unable to explain exactly why some of us prefer to do these tasks with the left hand and some with the right. Many theories are proposed and debated; studies yield data invariably suggestive but never conclusive. Moreover, as Howard Kushner systematically outlines in his short but meaty survey of the science and sociology of handedness, in some ways we are not that much further along than we were back in the days when our ancestors linked left-handedness to the sinister and the gauche, among many other undesirable traits, and just left it at that. An emeritus professor at Emory University and San Diego State, as well as a visiting scholar at the University of California – San Diego, Kushner brings academic credentials in both neuroscience and the history of science to his overview. In addition, he himself is left-handed, as was his mother (who like many left-handed children of her era was forcibly retrained to use her right), and the residua of personal experience echo through the book. Copyright 2017 Undark

Related chapters from BN8e: Chapter 19: Language and Lateralization
Related chapters from MM:Chapter 15: Brain Asymmetry, Spatial Cognition, and Language
Link ID: 24470 - Posted: 12.30.2017

Richard Easterbrook The news that left-handers excel at some sports but not others confirmed my thoughts that the 10% of people that make up us southpaws are used to punching above our weight. A study published in the journal Biology Letters concludes that being left-handed is an advantage in sports where time pressures are particularly severe – such as table tennis, or cricket, or squash. I am the exception to the rule – I manage to be equally rubbish at any sport regardless of whether it be fast or slow. My PE teacher told me at least I had one good tennis shot in me, but I felt that was a backhanded compliment. But if we left-handers lead at sports such as cricket or tennis, it is yet to make up for the inequality we face in everyday life. I always held dear the fact I was born a left-hander. It felt like a little badge of honour, like having a little superpower. To this day, I find myself scanning the room to seek out kindred spirits and upon discovering a fellow left-hander, giving them a knowing wink and a smile. Conversely, I find I am unfairly judged by right-handed folk. “Oh, you’re a lefty,” they say in a tone that would normally be reserved for someone with a terminal illness. In fact, many right-handers still mistakenly believe that left-handed people die younger, a theory long since debunked, thankfully. Meeting people for the first time is difficult, especially those who offer a handshake at the earliest opportunity from their right side. You either have to accept it and lead with your weaker right hand and face being judged poorly for dispatching such a weedy handshake, or persist with offering the left hand which then forces your new acquaintance with having to put down whatever they are holding in their left hand in order to fulfil a frankly quirky social custom. Why can’t we bump chests and be done with it? © 2017 Guardian News and Media Limited

Related chapters from BN8e: Chapter 19: Language and Lateralization
Related chapters from MM:Chapter 15: Brain Asymmetry, Spatial Cognition, and Language
Link ID: 24372 - Posted: 11.28.2017

By STEPH YIN Violins, cameras, school desks, computer mouses, can openers — these are just a few items that demonstrate how routinely disadvantaged left-handers are in this world. One notable exception may be sports. Whether it’s Lou Gehrig in baseball, Wayne Gretzky in ice hockey, Martina Navratilova in tennis or Oscar De La Hoya in boxing, some of the best athletes in history have been portsiders. But even in this realm, the southpaw advantage may vary, being more pronounced in sports where a player has less time to react to an opponent, like table tennis, according to Florian Loffing, a sports scientist at the University of Oldenburg in Germany and author of a study published Wednesday in Biology Letters. In such games, he found a higher proportion of lefties than in those with longer intervals between players’ actions. Including an analysis of the pressures of time shows “that there is an additional effect” in left-sider sports dynamics, said Kirsten Legerlotz, a professor of sport sciences at the Humboldt University of Berlin who was not involved in the research. Dr. Loffing’s “conclusion appears convincing,” she added, although it would need to be examined in other sports and verified with lab experiments. Dr. Loffing chose to analyze baseball, cricket, table tennis, badminton, tennis and squash, because they lent themselves to a standardized measure of time pressure, he said. For baseball and cricket, this involved the average time that elapsed between ball release and bat-ball contact in professional games. For the racket sports, he considered the intervals between racket-ball contact made by players in professional matches. He then tallied the number of lefties among each sport’s top 100 players, or pitchers and bowlers in the case of baseball and cricket, from 2009 to 2014. Comparing all six sports against one another, he found the proportion of southpaws increased as the time available for players to act decreased. Nine percent of the top players were left-dominant in the slowest contest, squash, while 30 percent of the best pitchers were lefties in the fastest, baseball. Over all, left-handedness was 2.6 times more likely in the sports with higher time constraints (baseball, cricket and table tennis) than in ones with lower time pressure (badminton, tennis and squash). © 2017 The New York Times Company

Related chapters from BN8e: Chapter 19: Language and Lateralization
Related chapters from MM:Chapter 15: Brain Asymmetry, Spatial Cognition, and Language
Link ID: 24346 - Posted: 11.22.2017

By Alice Klein Mothers hold their children more on the left and wild mammals seem to keep their young more on that so too, at least when fleeing predators. Now it seems many mammal babies prefer to approach their mother from one side too – and the explanation may lie in the contrasting talents of each half of the brain. In mammals, the brain’s right hemisphere is responsible for processing social cues and building relationships. It is also the half of the brain that receives signals from the left eye. Some researchers think this explains why human and ape mothers tend to cradle their babies on the left: it is so they can better monitor their facial expressions with their left eye. Now, Janeane Ingram at the University of Tasmania, Australia, and her colleagues have looked at whether animal infants also prefer to observe their mum from one side. The team studied 11 wild mammals from around the world: horses, reindeer, antelopes, oxen, sheep, walruses, three species of whale and two species of kangaroo. Whenever an infant approached its mother from behind, the researchers noted whether it positioned itself on its mum’s left or right side. They recorded almost 11,000 position choices for 175 infant-mother pairs. Infants of all species were more likely to position themselves so that their mother was on their left. This happened about three-quarters of the time. © Copyright Reed Business Information Ltd.

Related chapters from BN8e: Chapter 19: Language and Lateralization; Chapter 12: Sex: Evolutionary, Hormonal, and Neural Bases
Related chapters from MM:Chapter 15: Brain Asymmetry, Spatial Cognition, and Language; Chapter 8: Hormones and Sex
Link ID: 23076 - Posted: 01.10.2017

By Nala Rogers Treatments that zap the brain with magnets or electricity are rising in popularity, and some evidence suggests they can help lift depression. But scientists are starting to wonder whether they could be hitting the wrong place in left-handed patients. Now, two small studies suggest this could very well be the case. “This is the kind of question that’s been desperately needed for many years,” says Jim Coan, a clinical psychologist at the University of Virginia in Charlottesville who was not involved in the project. “Most researchers in this area, including myself, have selected samples that are strongly right-handed, just in order to avoid mess in the data.” Past studies have suggested that the spots targeted by both kinds of stimulation—located in the left hemisphere—are likely to process “approach” emotions such as happiness, curiosity, and anger, which drive people to reach out and engage with the world. Some studies have also hinted that the brain’s right hemisphere is more involved in so-called “avoidance” emotions such as sorrow and fear. But the studies that support this separation of emotion into the two halves of the brain have relied almost exclusively on right-handed individuals. To figure out whether something else was happening with lefties, University of Chicago in Illinois neuroscientist Daniel Casasanto designed two studies: one to link personality to patterns of brain activity and another to measure the outcome of common brain stimulation treatments in right-handed and left-handed individuals. The brain stimulation treatments were originally designed to treat depression by boosting feelings of happiness and engagement, which motivate “approach” behaviors such as exploring the world and interacting with friends. © 2016 American Association for the Advancement of Science.

Related chapters from BN8e: Chapter 19: Language and Lateralization; Chapter 15: Emotions, Aggression, and Stress
Related chapters from MM:Chapter 15: Brain Asymmetry, Spatial Cognition, and Language; Chapter 11: Emotions, Aggression, and Stress
Link ID: 21942 - Posted: 03.01.2016

Leo Benedictus It seems so obvious when you hear it, yet it could have shaped society for centuries without our knowing. According to research presented by Dr Daniel Casasanto to the American Association for the Advancement of Science annual conference in Washington DC, people just prefer things that are in front of their favourite hand. It could be products on a shelf, or applicants for a job. “Righties would on average choose the person or product on the right; lefties, on average, the person or product on the left,” Dr Casasanto explained. And, from his research conducted at the University of Chicago, it is easy to see how this could have serious political implications. “We found in a large simulated election, that compared to lefties, righties will choose the candidate they see on the right of the ballot paper about 15% more,” Dr Casasanto said. His theory, in simple terms, is that because people go through life with a “fluent side” and a “clumsy side”, they develop a kind of unconscious favouritism, even for things that don’t require them to use their hands. “It seems blindingly obvious that you will have a preference for that bit of space where you operate more frequently,” says Professor Philip Corr, a psychologist at City University, London. “You’ll feel more comfortable operating in that part of the world. Intuitively it makes sense to me.” Many papers have been published on the subject, but we still don’t really know why people don’t all use the same hand - or an even balance of the two, as do most primates.

Related chapters from BN8e: Chapter 19: Language and Lateralization; Chapter 15: Emotions, Aggression, and Stress
Related chapters from MM:Chapter 15: Brain Asymmetry, Spatial Cognition, and Language; Chapter 11: Emotions, Aggression, and Stress
Link ID: 21914 - Posted: 02.19.2016

by Sarah Zielinski Last year in Australia, I visited Featherdale Wildlife Park where, in a couple of areas, kangaroos and wallabies hop amongst the tourists. For a dollar, you can buy an ice cream cone full of grass for the marsupials to eat. But if you’re not careful, an animal will quickly grab the cone out of your hand and feed itself. Now I’m wishing that I had paid more attention to that grabbing motion. Kangaroos are lefties, scientists report June 18 in Current Biology. And the preference for one hand over the other may be linked to the ability to walk on two legs. Humans show a definite preference for one hand over the other, usually the right. This handedness had been considered a distinctly human trait. But scientists have found more and more evidence that other species have such preferences as well. Female domestic cats, for instance, tend to use their right paws and males their left. Andrey Giljov of Saint Petersburg State University in Russia and colleagues were curious about the evolution of handedness and looked to marsupials, since these animals are an early offshoot of the mammal lineage. They observed four species in the wild — red kangaroos, eastern gray kangaroos, red-necked wallabies and Goodfellow’s tree kangaroos — performing tasks such as grooming and feeding. © Society for Science & the Public 2000 - 2015.

Related chapters from BN8e: Chapter 19: Language and Lateralization
Related chapters from MM:Chapter 15: Brain Asymmetry, Spatial Cognition, and Language
Link ID: 21075 - Posted: 06.20.2015

Jason G Goldman We humans don’t typically agree on all that much, but there is at least one thing that an impressive amount of us accept: which hand is easiest to control. If you use one hand for writing, you probably use the same one for eating as well, and most of us – around 85% of our species – prefer our right hands. In fact, "there has never been any report of a human population in which left-handed individuals predominate", according to archaeologist Natalie Uomini at the University of Liverpool in the UK. Lateralisation of limb use – that is, a bias towards one side or the other – usually begins in the brain. We know that some tasks are largely controlled by brain activity in the left hemisphere, while the right hemisphere governs other tasks. Confusingly, there is some crossing of nerves between the body and the brain, which means it’s actually the left side of the brain that has more control over the right side of the body and vice versa. In other words, the brain’s left hemisphere helps control the operation of the right hand, eye, leg and so on. Some argue that this division of neurological labour has been a feature of animals for half a billion years. Perhaps it evolved because it is more efficient to allow the two hemispheres to carry out different computations at the same time. The left side of the brain, for instance, might have evolved to carry out routine operations – things like foraging for food – while the right side was kept free to detect and react rapidly to unexpected challenges in the environment – an approaching predator, for instance. This can be seen in various fish, toads and birds, which are all more likely to attack prey seen in the right eye. © 2014 BBC.

Related chapters from BN8e: Chapter 19: Language and Lateralization; Chapter 6: Evolution of the Brain and Behavior
Related chapters from MM:Chapter 15: Brain Asymmetry, Spatial Cognition, and Language
Link ID: 20426 - Posted: 12.18.2014

|By Sam Kean It is possible to take the idea of left/right differences within the brain too far: it’s not like one side of the brain talks or emotes or recognizes faces all by itself while the other one just sits there twiddling its neurons. But the left and right hemispheres of the human brain do show striking differences in some areas, especially with regard to language, the trait that best defines us as human beings. Scientists suspect that left-right specialization first evolved many millions of years ago, since many other animals show subtle hemispheric differences: they prefer to use one claw or paw to eat, for instance, or they strike at prey more often in one direction than another. Before this time, the left brain and right brain probably monitored sensory data and recorded details about the world to an equal degree. But there’s no good reason for both hemispheres to do the same basic job, not if the corpus callosum—a huge bundle of fibers that connects the left and right brain—can transmit data between them. So the brain eliminated the redundancy, and the left brain took on new tasks. This process accelerated in human beings, and we humans show far greater left/right differences than any other animal. In the course of its evolution the left brain also took on the crucial role of master interpreter. Neuroscientists have long debated whether certain people have two independent minds running in parallel inside their skulls. That sounds spooky, but some evidence suggests yes. For example, there are split-brain patients, who had their corpus callosums surgically severed to help control epilepsy and whose left and right brain cannot communicate as a result. Split-brain patients have little trouble drawing two different geometric figures at the same time, one with each hand. Normal people bomb this test. (Try it, and you’ll see how mind-bendingly hard it is.) Some neuroscientists scoff at these anecdotes, saying the claims for two separate minds are exaggerated. But one thing is certain: two minds or no, split-brain people feel mentally unified; they never feel the two hemispheres fighting for control, or feel their consciousness flipping back and forth. That’s because one hemisphere, usually the left, takes charge. And many neuroscientists argue that the same thing happens in normal brains. One hemisphere probably always dominates the mind, a role that neuroscientist Michael Gazzaniga called the interpreter. (Per George W. Bush, you could also call it “the decider.”) © 2014 Scientific American

Related chapters from BN8e: Chapter 19: Language and Lateralization
Related chapters from MM:Chapter 15: Brain Asymmetry, Spatial Cognition, and Language
Link ID: 19625 - Posted: 05.16.2014

by Anil Ananthaswamy Children born with split brains – whereby the two hemispheres of their brains are not connected – can develop new brain wiring that helps to connect the two halves, according to brain scans of people with the condition. Such circuitry is not present in normal brains, and explains how some people with split brains can still maintain normal function. It also suggests that the developing brain is even more adaptable than previously thought. Research into people with split brains goes back to the 1960s, when neuroscientists studied people who had undergone brain surgery to treat particularly severe epilepsy. The surgery involved cutting the corpus callosum, the thick bundle of neuronal fibres that connects the brain's two halves. This disconnection prevented epileptic seizures spreading from one brain hemisphere to the other. The recipients of such split-brain surgery showed a form of disconnection syndrome whereby the two halves of their brains could not exchange information. For instance, if a patient touched an object with their left hand without seeing the object, they would be unable to name it. That is because sensory-motor signals from the left hand are processed in the right hemisphere. To put a name to the object, the tactile information from the hand has to reach the brain's left hemisphere, the seat of language. With the central connection between hemispheres severed, the object's naming information cannot be retrieved. Conversely, if that person were to touch an object with their right hand without seeing it, the sensory-motor signals from that hand would go to the left hemisphere, which hosts the brain's language centres, making naming the object easy. However, children born without a corpus callosum – and therefore whose two brain hemispheres are separated – can often pass such tactile naming tests when they are old enough to take them. Their brain hemispheres are obviously communicating, but it wasn't clear how. © Copyright Reed Business Information Ltd

Related chapters from BN8e: Chapter 19: Language and Lateralization; Chapter 7: Life-Span Development of the Brain and Behavior
Related chapters from MM:Chapter 15: Brain Asymmetry, Spatial Cognition, and Language; Chapter 13: Memory, Learning, and Development
Link ID: 19609 - Posted: 05.13.2014

By Tina Hesman Saey About 10 percent of people prefer using their left hand. That ratio is found in every population in the world and scientists have long suspected that genetics controls hand preference. But finding the genes has been no simple task, says Chris McManus, a neuropsychologist at University College London who studies handedness but was not involved in the new research. “There’s no single gene for the direction of handedness. That’s clear,” McManus says. Dozens of genes are probably involved, he says, which means that one person’s left-handedness might be caused by a variant in one gene, while another lefty might carry variants in an entirely different gene. To find handedness genes, William Brandler, a geneticist at the University of Oxford, and colleagues conducted a statistical sweep of DNA from 3,394 people. Statistical searches such as this are known as genome-wide association studies; scientists often do such studies to uncover genes that contribute to complex diseases or traits such as diabetes and height. The people in this study had taken tests involving moving pegs on a board. The difference in the amount of time they took with one hand versus the other reflected how strongly left- or right-handed they were. A variant in a gene called PCSK6 was most tightly linked with strong hand preference, the researchers report in the Sept. 12 PLOS Genetics.. The gene has been implicated in handedness before, including in a 2011 study by the same research group. PCSK6 is involved in the asymmetrical positioning of internal organs in organisms from snails to vertebrates. © Society for Science & the Public 2000 - 2013

Related chapters from BN8e: Chapter 19: Language and Lateralization
Related chapters from MM:Chapter 15: Brain Asymmetry, Spatial Cognition, and Language
Link ID: 18647 - Posted: 09.14.2013

By Scott Barry Kaufman So yea, you know how the left brain is really realistic, analytical, practical, organized, and logical, and the right brain is so darn creative, passionate, sensual, tasteful, colorful, vivid, and poetic? No. Just no. Stop it. Please. Thoughtful cognitive neuroscientists such as Rex Jung, Darya Zabelina, Andreas Fink, John Kounios, Mark Beeman, Kalina Christoff, Oshin Vartanian, Jeremy Gray, Hikaru Takeuchi and others are on the forefront of investigating what actually happens in the brain during the creative process. And their findings are overturning conventional notions surrounding the neuroscience of creativity. The latest findings from the real neuroscience of creativity suggest that the right brain/left brain distinction is not the right one when it comes to understanding how creativity is implemented in the brain. Creativity does not involve a single brain region or single side of the brain. Instead, the entire creative process– from the initial burst of inspiration to the final polished product– consists of many interacting cognitive processes and emotions. Depending on the stage of the creative process, and what you’re actually attempting to create, different brain regions are recruited to handle the task. Importantly, many of these brain regions work as a team to get the job done, and many recruit structures from both the left and right side of the brain. In recent years, evidence has accumulated suggesting that “cognition results from the dynamic interactions of distributed brain areas operating in large-scale networks.” © 2013 Scientific American

Related chapters from BN8e: Chapter 19: Language and Lateralization; Chapter 18: Attention and Higher Cognition
Related chapters from MM:Chapter 15: Brain Asymmetry, Spatial Cognition, and Language; Chapter 14: Attention and Consciousness
Link ID: 18528 - Posted: 08.20.2013

by Andrew Porterfield Honey bees may have only a fraction of our neurons—just under a million versus our tens of billions—but our brains aren't so different. Take sidedness. The human brain is divided into right and left sides—our right brain controls the left side of our body and vice versa. New research reveals that something similar happens in bees. When scientists removed the right or left antenna of honey bees, those insects with intact right antennae more quickly recognized bees from the same hive, stuck out their tongues (showing willingness to feed), and fended off invaders. Bees with just their left antennae took longer to recognize bees, didn't want to feed, and mistook familiar bees for foreign ones. This suggests, the team concludes today in Scientific Reports, that bee brains have a sidedness just like ours do. The researchers also think that right antennae might control other bee behavior, like their sophisticated, mysterious "waggle dance" to indicate food. But there's no buzz for the left-antennaed. © 2010 American Association for the Advancement of Science

Related chapters from BN8e: Chapter 19: Language and Lateralization; Chapter 6: Evolution of the Brain and Behavior
Related chapters from MM:Chapter 15: Brain Asymmetry, Spatial Cognition, and Language
Link ID: 18320 - Posted: 06.29.2013

By Felicity Muth I recently came across an article entitled ‘Advantages in exploring a new environment with the left eye in lizards’ and I couldn’t help but read more. In this study, conducted in Italy, scientists caught 44 wall lizards and glued eye patches on to them (using a paper glue that is harmless to the lizards as they can shed and renew their skin). Half the lizards had their left eye covered, and half had their right eye covered. The lizards were then let into a maze for 20 minutes to see how they fared with turning left and right. The ones that were allowed to use just their left eye were much faster than those that could just use their right eye at turning both left and right. In addition to this, they made fewer stops, seeming to be less hesitant and indecisive than the right-eyed individuals. However, this was only the case when the lizard had to make a choice between turning left or right, not when they only had the choice to turn one way. Why might this be the case? Well, like a lot of vertebrates, lizards have lateralized brains. This means that the brain is divided in two halves, and some functions are specialized to one half. The classic example of this in humans is Broca’s area (associated with speech), which is found in the left hemisphere of the brain in 95% of us. Similar to how humans on the whole prefer to use their right hand, it seems that lizards generally prefer to use their left eye. As with humans, lizard optic nerve fibres are crossed over, meaning that control of the left eye comes from the right hemisphere of the brain and vice versa. As these lizards predominantly use their left eye, this indicates that in this species, something in the right side of their brain is specialised in attending to spatial cues. © 2013 Scientific American

Related chapters from BN8e: Chapter 19: Language and Lateralization; Chapter 10: Vision: From Eye to Brain
Related chapters from MM:Chapter 15: Brain Asymmetry, Spatial Cognition, and Language; Chapter 7: Vision: From Eye to Brain
Link ID: 18261 - Posted: 06.12.2013

by Helen Thomson "I was sitting on the toilet. I suddenly felt an explosion in the left side of my head and ended up on the floor. I think the only thing that kept me conscious was that I didn't want to be found with my pants down. Then the other side of my head went bang! I woke up in hospital and looked out of the window to see the tree was sprouting numbers. 3, 6, 9. Then I started talking in rhyme…" Ten days after having a subarachnoid haemorrhage – a stroke caused by bleeding in and around the brain – Tommy McHugh, an ex-con who'd been in his fair share of scraps, became a new man, with a personality that nobody recognised. When he was a young man, Tommy did time in prison. But after his stroke at age 51, everything changed. "I could taste the femininity inside of myself," he said. "My head was full of rhymes and images and pictures." Not only did he feel a sudden urge to write poetry, but he also began to paint and draw obsessively for up to 19 hours a day. He was never artistic before – in fact, he joked that he'd never even been in an art gallery "except to maybe steal something". Desperate to find out what was going on, Tommy wrote to several neuroscientists and end up working closely with Alice Flaherty at Harvard Medical School and Mark Lythgoe at University College London. © Copyright Reed Business Information Ltd.

Related chapters from BN8e: Chapter 19: Language and Lateralization
Related chapters from MM:Chapter 15: Brain Asymmetry, Spatial Cognition, and Language
Link ID: 18142 - Posted: 05.11.2013