Chapter 19. Language and Hemispheric Asymmetry

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By Denise D. Cummins Looking directly at the camera, NPR's Skunk Bear host Adam Cole laments, "It's pretty clear that I'll never be able to have a real human-style conversation with an ape.” In his short and very entertaining video, Cole summarizes decades of research aimed at teaching apes human language, all of which, we are to understand, came to naught. But what the video actually shows us is how little the average person (and many scientists) understands about language. At one point, Cole tells his dog to sit, and the dog sits. This, he tells us, is not evidence that the dog knows English. But actually, it is. The dog's behavior shows us that he is capable of understanding the simple concept of sitting, that he is capable of distinguishing the verbal signal "sit" from other verbal signals, and that he is capable of connecting the two. This isn't rocket science, it isn't magic, and it isn't anthropomorphizing. It is just the way word learning works. In studies conducted at the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, a border collie named Rico was taught the meanings of 200 words. He could even use theprocess of elimination to figure out unfamiliar words: If he already knew the word "ball,” and his trainer showed him a ball and a stick and told him to get the "stick,” he would bring the stick. He could remember new words even after a month of not hearing them. © 2017 Scientific American,

Keyword: Animal Communication; Language
Link ID: 23977 - Posted: 08.19.2017

By NICHOLAS BAKALAR The incidence of stroke has declined in recent years, but only in men. Researchers studied stroke incidence in four periods from 1993 to 2010 in five counties in Ohio and Kentucky. There were 7,710 strokes all together, 57.2 percent of them in women. After adjusting for age and race, they found that stroke incidence in men had decreased to 192 per hundred thousand men in 2010, down from 263 in 1993–94. But for women the incidence was 198 per hundred thousand in 2010, down from 217 in 1993–94, a statistically insignificant change. The study is in Neurology. Most of the difference was in ischemic stroke, the most common cause, resulting from a blocked blood vessel supplying blood to the brain. No one knows why there has been no improvement in women, but the lead author, Dr. Tracy E. Madsen, an assistant professor of emergency medicine at Brown, said that some risk factors have a stronger effect in women than in men. Risk factors for stroke include high blood pressure, heart disease, diabetes and smoking. “Maybe we’re not controlling risk factors to the same extent in women. Or maybe there’s a biological difference in the way these risk factors cause strokes in men versus women.” In any case, Dr. Madsen said, “It’s important for women to know they are at risk. Stroke has been considered a male disease, but we know that it is very prevalent in women and has a high risk of disability and death.” © 2017 The New York Times Company

Keyword: Stroke; Sexual Behavior
Link ID: 23939 - Posted: 08.10.2017

By Daniel Barron Conrad was 17 months old when Dave, his grandfather, was babysitting him at their home in Temple, Texas. The two had been playing in the pool and went inside for a break. Dave set to unloading dishes in the dishwasher, unaware that Conrad had snuck back outside. As he finished the dishes, Dave looked out the window and noticed something odd. There was what looked like a floating bundle of clothes in the swimming pool. It was his grandson. Fortunately, Conrad responded to cardiopulmonary resuscitation (CPR), but it’s unclear how long his lungs—and his brain—went without oxygen. Drowning is the second most common cause of accidental death in children to age four. As in Conrad’s case, CPR is fortunately very successful, with 66 percent of nearly drowned children surviving. But even when resuscitated, the seconds and minutes that the brain is deprived of oxygen come at a great cost. This type of damage is known as anoxic brain injury. Anoxic brain injury is a clinical term that indicates damage to the brain that occurs due to lack of oxygen. There is a spectrum of injury ranging from complete recovery to minor to widespread brain damage. Within this spectrum lies what is known as the disorders of consciousness, with the extent of damage being proportional to the loss of consciousness. In the case of nearly drowned children, the injury is frequently thought to be widespread. Nearly drowned children are labeled “minimally conscious” or even in a “persistent vegetative state” (with no consciousness) and the prevailing medical prognosis is grim: treatment and recovery is difficult if not impossible. © 2017 Scientific American,

Keyword: Development of the Brain; Brain Injury/Concussion
Link ID: 23926 - Posted: 08.08.2017

Jean M. Twenge One day last summer, around noon, I called Athena, a 13-year-old who lives in Houston, Texas. She answered her phone—she’s had an iPhone since she was 11—sounding as if she’d just woken up. We chatted about her favorite songs and TV shows, and I asked her what she likes to do with her friends. “We go to the mall,” she said. “Do your parents drop you off?,” I asked, recalling my own middle-school days, in the 1980s, when I’d enjoy a few parent-free hours shopping with my friends. “No—I go with my family,” she replied. “We’ll go with my mom and brothers and walk a little behind them. I just have to tell my mom where we’re going. I have to check in every hour or every 30 minutes.” Those mall trips are infrequent—about once a month. More often, Athena and her friends spend time together on their phones, unchaperoned. Unlike the teens of my generation, who might have spent an evening tying up the family landline with gossip, they talk on Snapchat, the smartphone app that allows users to send pictures and videos that quickly disappear. They make sure to keep up their Snapstreaks, which show how many days in a row they have Snapchatted with each other. Sometimes they save screenshots of particularly ridiculous pictures of friends. “It’s good blackmail,” Athena said. (Because she’s a minor, I’m not using her real name.) She told me she’d spent most of the summer hanging out alone in her room with her phone. That’s just the way her generation is, she said. “We didn’t have a choice to know any life without iPads or iPhones. I think we like our phones more than we like actual people.” Copyright (c) 2017 by The Atlantic Monthly Group.

Keyword: Depression
Link ID: 23925 - Posted: 08.08.2017

By Erin Blakemore Do you talk to yourself? Don’t sweat it: Scientists say you’re not alone. And the ways in which you chatter to yourself, both in your head and out loud, are changing what neuroscientists know about the human brain. Writing in Scientific American, psychologist Charles Fernyhough reveals why we’re our best conversational partners. Scientists have only recently learned how to study self-talk — and it’s opening up exciting new avenues of research. It turns out there are two ways of chatting yourself up. In “inner speech,” you speak to yourself without making sound. With “private speech,” you do the same thing, just out loud. This chatter serves varied purposes: It can help people control themselves and relate to others. But it’s notoriously hard to study. So Fernyhough and colleagues figured out some inventive ways to prompt people to talk to themselves as they lay inside a functional magnetic resonance imaging, or fMRI, scanner. When they studied the brains of people who talked to themselves internally, the team noticed that spontaneous inner speech activates a different part of the brain than words that the participants were asked to say aloud. And people whose self-talk takes the form of a monologue seem to activate different brain areas than those who carry on a dialogue in their heads. © 1996-2017 The Washington Post

Keyword: Consciousness; Language
Link ID: 23924 - Posted: 08.07.2017

By Mo Costandi The controversy began about 10 years ago, when it emerged that the National Football League had first tried to cover up evidence linking repetitive head injuries in players to chronic traumatic encephalopathy (CTE), a progressive neurodegenerative disorder, and then to discredit the scientists doing the work. Since then evidence supporting this link has grown as an increasing number of players have come forward to report that they are suffering from depression, and some have committed suicide. And yet, exactly how repetitive head injuries are linked to CTE development and the psychiatric symptoms associated with it is still a matter of debate. The largest-ever study of its kind has now given the most compelling evidence yet linking repetitive head impacts in football players to CTE. The study, published recently in JAMA The Journal of the American Medical Association, has notable limitations, however. It has also sparked calls for more research to measure the impact of head blows on players over the course of a lifetime. The new work builds on findings from 2013: neuropathologist Ann McKee of Boston University and her colleagues published a postmortem report of 68 male athletes and military veterans with CTE, in which they described a spectrum of pathological signatures associated with the condition. McKee and colleagues observed two distinct sets of clinical symptoms: one involving disturbances in mood and behavior, which was seen in the younger subjects, and the other including cognitive impairments, which developed at an older age. © 2017 Scientific American

Keyword: Brain Injury/Concussion
Link ID: 23920 - Posted: 08.05.2017

Emily Siner The Grand Ole Opry in Nashville, Tenn., is country music's Holy Land. It's home to the weekly radio show that put country music on the national map in 1925. And it's where this summer, 30 people with Williams syndrome eagerly arrived backstage. Williams syndrome is a rare genetic disorder that can cause developmental disabilities. People with the condition are often known for their outgoing personalities and their profound love of music. Scientists are still trying to figure out where this musical affinity comes from and how it can help them overcome their challenges. That's why 12 years ago, researchers at Vanderbilt University set up a summer camp for people with Williams syndrome. For a week every summer, campers come to Nashville to immerse themselves in country music and participate in cutting-edge research. This isn't the only summer camp for people with Williams syndrome, but it is unique in its distinctive country flair. It's organized by the Vanderbilt Kennedy Center, whose faculty and staff focus on developmental disabilities. Eight years ago, the Academy of Country Music's philanthropic arm, ACM Lifting Lives, started funding the program. Campers spend the week meeting musicians and visiting recording studios, even writing an original song. This year, they teamed up with one of country's hottest stars, Dierks Bentley, on that. And they get a backstage tour of the Grand Ole Opry led by Clancey Hopper, who has Williams syndrome herself and attended the Nashville camp for eight years before applying for a job at the Opry. © 2017 npr

Keyword: Language; Development of the Brain
Link ID: 23904 - Posted: 08.01.2017

By Giorgia Guglielmi Tits amazing are birds Japanese. If you didn’t get that, you wouldn’t be alone: Humans figure out the meaning of sentences like this using grammatical rules such as word order. It turns out that Japanese tits, social birds that live in Japan and the Russian Far East, do it too. These wild birds respond to calls they’ve never heard before only if the chirps are in the right order, researchers report today in Current Biology. When a predator threatens the flock, Japanese tits produce something called a “mobbing call,” with the sequence ABC-D. By itself, the ABC part of the call means “danger.” But the D part of the call—similar to the “recruitment call” of a close relative, the willow tit—attracts flock members when there’s something to share, such as food. When the two parts are produced together, Japanese tits flock together to mob the intruder. To find out if the order of the calls mattered, researchers created a song that Japanese tits had never heard before—an artificial sequence made up of the Japanese tit’s ABC alert, followed by the willow tit’s recruitment call, tӓӓ. (You can listen to them, above.) They then played it from a loudspeaker for a flock of nearby tits. When Japanese tits heard the ABC- tӓӓ call, they turned their heads, looking for a predator, as they approached the loudspeaker. But when the artificial sequence was reversed (tӓӓ-ABC), the birds didn’t react. © 2017 American Association for the Advancement of Science.

Keyword: Animal Communication; Language
Link ID: 23889 - Posted: 07.28.2017

By Joe Ward, Josh Williams and Sam Manchester Dr. Ann McKee, a neuropathologist, has examined the brains of 202 deceased football players. A broad survey of her findings was published on Tuesday in The Journal of the American Medical Association. Of the 202 players, 111 of them played in the N.F.L. — and 110 of those were found to have chronic traumatic encephalopathy, or C.T.E., the degenerative disease believed to be caused by repeated blows to the head. C.T.E. causes myriad symptoms, including memory loss, confusion, depression and dementia. The problems can arise years after the blows to the head have stopped. The brains here are from players who died as young as 23 and as old as 89. And they are from every position on the field — quarterbacks, running backs and linebackers, and even a place-kicker and a punter. They are from players you have never heard of and players, like Ken Stabler, who are enshrined in the Hall of Fame. Some of the brains cannot be publicly identified, per the families’ wishes. The image above is from the brain of Ronnie Caveness, a linebacker for the Houston Oilers and Kansas City Chiefs. In college, he helped the Arkansas Razorbacks go undefeated in 1964. One of his teammates was Jerry Jones, now the owner of the Dallas Cowboys. Jones has rejected the belief that there is a link between football and C.T.E. The image above is from the brain of Ollie Matson, who played 14 seasons in the N.F.L. — after winning two medals on the track at the 1952 Helsinki Games. He died in 2011 at age 80 after being mostly bedridden with dementia, his nephew told The Associated Press, adding that Matson hadn’t spoken in four years. Dr. McKee, chief of neuropathology at the VA Boston Healthcare System and director of the CTE Center at Boston University, has amassed the largest C.T.E. brain bank in the world. But the brains of some other players found to have the disease — like Junior Seau, Mike Webster and Andre Waters — were examined elsewhere. © 2017 The New York Times Company

Keyword: Brain Injury/Concussion
Link ID: 23880 - Posted: 07.26.2017

Tom Goldman As the country starts to get back into its most popular professional team sport, there is a reminder of how dangerous football can be. An updated study published Tuesday by the Journal of the American Medical Association on football players and the degenerative brain disease chronic traumatic encephalopathy reveals a striking result among NFL players. The study examined the brains of deceased former football players (CTE can only be diagnosed after death) and found that 110 out of 111 brains of those who played in the NFL had CTE. CTE has been linked to repeated blows to the head — the 2015 movie Concussion chronicled the discovery of CTE's connection to football. In the study, researchers examined the brains of 202 deceased former football players at all levels. Nearly 88 percent of all the brains, 177, had CTE. Three of 14 who had played only in high school had CTE, 48 of 53 college players, 9 of 14 semiprofessional players, and 7 of 8 Canadian Football League players. CTE was not found in the brains of two who played football before high school. According to the study's senior author, Dr. Ann McKee, "this is by far the largest [study] of individuals who developed CTE that has ever been described. And it only includes individuals who are exposed to head trauma by participation in football." © 2017 npr

Keyword: Brain Injury/Concussion
Link ID: 23879 - Posted: 07.26.2017

By Virginia Morell Frogs, birds, monkeys, and humans make a variety of sounds expressing emotions. And because that ability is shared by every land-dwelling animal with a backbone, Charles Darwin argued that these cries have a common origin. Humans can recognize the emotions in the voices of other mammals, including cats and dogs. To find out whether we can also do this for nonmammals, scientists gathered recordings from nine species, including the hourglass tree frog (above), American alligator, common raven, Barbary macaque, and Tamil-speaking humans in two emotional states: highly and mildly aroused. They played the calls to 75 people—men and women who spoke English, German, or Mandarin—and asked them to judge whether the animal was very excited or subdued. You can try it yourself below: Participants easily passed the tests. Some 90% of listeners distinguished between the excited and calmer sounds of the tree frogs (which were calling for mates), and 87% scored the alligator calls correctly. Sixty-two percent were right about the ravens’ calls of alarm. © 2017 American Association for the Advancement of Science.

Keyword: Animal Communication; Emotions
Link ID: 23877 - Posted: 07.26.2017

Ryan Kellman The modern Planet of the Apes reboot begins with a research chimpanzee being raised in an American home. It's a pretty plausible premise — that exact scenario has played out in the real world many times. On June 26, 1931, for example, Luella and Winthrop Kellogg pulled a baby female chimpanzee away from her mother and brought her to live in their home in Orange Park, Fla. The Kelloggs were comparative psychologists. Their plan was to raise the chimpanzee, Gua, alongside their own infant son, Donald, and see if she picked up human language. According to the book they wrote about the experiment, Luella wasn't initially on board: ... the enthusiasm of one of us met with so much resistance from the other that it appeared likely we could never come to an agreement upon whether or not we should even attempt such an undertaking. But attempt it they did. The Kelloggs performed a slew of tests on Donald and Gua. How good were their reflexes? How many words did they recognize? How did they react to the sound of a gunshot? What sound did each infant's skull make when tapped by a spoon? (Donald's produced "a dull thud" while Gua's made the sound of a "mallet upon a wooden croquet ball.") Chimpanzees develop faster than humans, so Gua outshone Donald when it came to most tasks. She even learned to respond to English phrases like "Don't touch!" and "Get down!" But unlike the apes in the movies, Gua never learned to speak. © 2017 npr

Keyword: Language; Evolution
Link ID: 23871 - Posted: 07.25.2017

By CLAY ROUTLEDGE Are Americans becoming less religious? It depends on what you mean by “religious.” Polls certainly indicate a decline in religious affiliation, practice and belief. Just a couple of decades ago, about 95 percent of Americans reported belonging to a religious group. This number is now around 75 percent. And far fewer are actively religious: The percentage of regular churchgoers may be as low as 15 to 20 percent. As for religious belief, the Pew Research Center found that from 2007 to 2014 the percentage of Americans who reported being absolutely confident God exists dropped from 71 percent to 63 percent. Nonetheless, there is reason to doubt the death of religion, or at least the death of what you might call the “religious mind” — our concern with existential questions and our search for meaning. A growing body of research suggests that the evidence for a decline in traditional religious belief, identity and practice does not reflect a decline in this underlying spiritual inclination. Ask yourself: Why are people religious to begin with? One view is that religion is an ancient way of understanding and organizing the world that persists largely because societies pass it down from generation to generation. This view is related to the idea that the rise of science entails the fall of religion. It also assumes that the strength of religion is best measured by how much doctrine people accept and how observant they are. This view, however, does not capture the fundamental nature of the religious mind — our awareness of, and need to reckon with, the transience and fragility of our existence, and how small and unimportant we seem to be in the grand scheme of things. In short: our quest for significance. © 2017 The New York Times Company

Keyword: Attention; Emotions
Link ID: 23868 - Posted: 07.24.2017

Jon Hamilton Professional fighter Gina Mazany practices during a training session at Xtreme Couture Mixed Martial Arts in Las Vegas. She well remembers her first concussion — which came in her first fight. "I was throwing up that night, Mazany says. Bridget Bennett for NPR Gina Mazany grew up in Anchorage, Alaska. And that's where she had her first fight. "It was right after I turned 18," she recalls. A local bar had a boxing ring, and Mazany decided to give it a shot. Her opponent was an older woman with a "mom haircut." "She beat the crap out of me," Mazany says. "Like she didn't knock me out, she didn't finish me. But she just knocked me around for three rounds. And I remember, later that night I was very, very nauseous. I was throwing up that night." It was her first concussion. Concussions are just part of her sport, Mazany figures, but says she tries to protect herself, and to not give anyone else a head injury--at least in training. Bridget Bennett for NPR Thanks to research on boxers and football players, both athletes and the public are becoming more aware of the dangers of sports-related head injuries. Yet there is little data on participants like Mazany. That's because, unlike the vast majority of athletes studied, she is a woman. "We classically have always known the male response to brain injury," says Mark Burns, at Georgetown University. But there have been remarkably few studies of females. The bias runs throughout the scientific literature, even in studies of mice. © 2017 npr

Keyword: Brain Injury/Concussion
Link ID: 23865 - Posted: 07.24.2017

By Ryan Cross Whether caused by a car accident that slams your head into the dashboard or repeated blows to your cranium from high-contact sports, traumatic brain injury can be permanent. There are no drugs to reverse the cognitive decline and memory loss, and any surgical interventions must be carried out within hours to be effective, according to the current medical wisdom. But a compound previously used to enhance memory in mice may offer hope: Rodents who took it up to a month after a concussion had memory capabilities similar to those that had never been injured. The study “offers a glimmer of hope for our traumatic brain injury patients,” says Cesario Borlongan, a neuroscientist who studies brain aging and repair at the University of South Florida in Tampa. Borlongan, who reviewed the new paper, notes that its findings are especially important in the clinic, where most rehabilitation focuses on improving motor—not cognitive—function. Traumatic brain injuries, which cause cell death and inflammation in the brain, affect 2 million Americans each year. But the condition is difficult to study, in part because every fall, concussion, or blow to the head is different. Some result in bleeding and swelling, which must be treated immediately by drilling into the skull to relieve pressure. But under the microscope, even less severe cases appear to trigger an “integrated stress response,” which throws protein synthesis in neurons out of whack and may make long-term memory formation difficult. © 2017 American Association for the Advancement of Science.

Keyword: Learning & Memory; Brain Injury/Concussion
Link ID: 23825 - Posted: 07.11.2017

Nicola Davis People who drink coffee have a lower risk of dying from a host of causes, including heart disease, stroke and liver disease, research suggests – but experts say it’s unclear whether the health boost is down to the brew itself. The connection, revealed in two large studies, was found to hold regardless of whether the coffee was caffeinated or not, with the effect higher among those who drank more cups of coffee a day. But scientists say that the link might just be down to coffee-drinkers having healthier behaviours. “It is plausible that there is something else behind this that is causing this relationship,” said Marc Gunter, a co-author of one of the studies, from the International Agency for Research on Cancer. But, he added, based on the consistency of the results he would be surprised if coffee itself didn’t play a role in reducing the risk of death. About 2.25bn cups of coffee are consumed worldwide every day. While previous studies have suggested coffee might have health benefits, the latest research involves large and diverse cohorts of participants. The first study looked at coffee consumption among more than 185,000 white and non-white participants, recruited in the early 1990s and followed up for an average of over 16 years. The results revealed that drinking one cup of coffee a day was linked to a 12% lower risk of death at any age, from any cause while those drinking two or three cups a day had an 18% lower risk, with the association not linked to ethnicity. © 2017 Guardian News and Media Limited

Keyword: Drug Abuse; Stroke
Link ID: 23823 - Posted: 07.11.2017

By Linda Geddes BILLIONS of dollars have been spent in search of treatments for psychiatric conditions and brain disorders, when a cheap and effective drug may have been right under our noses: light. Now hospitals are turning to light to treat depression, strokes and Parkinson’s disease, using it to hit the reset button on our internal clocks. From green light soothing the pain of migraine, to blue light reducing organ damage during surgery, recent small studies have uncovered some intriguing effects of this therapy. But apart from easing seasonal affective disorder, we’ve been slow to embrace light as a serious contender for treating neurological conditions. We’ve known for 15 years that a special kind of receptor in our eyes transmits information directly to the body’s master clock, as well as other brain areas that control mood and alertness. These cells are particularly responsive to bluish light, including sunlight. These receptors enable light to act as a powerful reset switch, keeping the clock in our brain synced to the outside world. But this clock can fall out of sync or weaken as part of ageing or a range of disorders – a problem doctors are now starting to treat with light. Most hospitals have small windows and 24-hour lighting, both of which might exacerbate health problems. To tackle this, several hospitals in Europe and the US are installing dynamic “solid state” lighting, which changes like daylight over the course of a day. Such lights can, for example, shine bright whitish-blue in the morning, grow warmer and dimmer throughout the day, and turn orange or switch off at night. © Copyright New Scientist Ltd.

Keyword: Biological Rhythms; Stroke
Link ID: 23808 - Posted: 07.06.2017

By Sandrine Ceurstemont Bird or beast? A cuckoo seems to have learned how to mimic the sounds made by the pig-like peccaries it lives alongside, perhaps to ward off predators. The Neomorphus ground cuckoos live in forests in Central and South America, where they often follow herds of wild peccaries so they can feed on the invertebrates that the peccaries disturb as they plough through the leaf litter. Ecologists have noticed that when the cuckoos clap their beaks together they sound a lot like the tooth clacks the peccaries make to deter large predatory cats. To find out whether this is just coincidence or evidence of mimicry, Cibele Biondo at the Federal University of ABC in Brazil and her team analysed the cuckoo and peccary sounds, and compared them with the beak clapping sounds made by roadrunners – close relatives of the ground cuckoos. Logically, the cuckoos should sound most similar to roadrunners, given that the two are closely related. But the analysis suggested otherwise. “The acoustic characteristics are more similar to the teeth clacking of peccaries,” says Biondo. She suspects that cuckoos have something to gain by imitating the peccaries, particularly in the dark, dense forests where predators rely on hearing as much as vision. “Cuckoos may deceive predators by making it appear that peccaries are present when they are not,” says Biondo. © Copyright New Scientist Ltd.

Keyword: Evolution; Animal Communication
Link ID: 23802 - Posted: 07.04.2017

By Dina Fine Maron Not all of Mitchell Elkind’s stroke patients are on social security. In recent years he has treated devastating attacks in people as young as 18. And he is not alone. A growing body of research indicates strokes among U.S. millennials—ages 18 to 34—have soared in recent years. But an analysis by Scientific American has revealed significant differences in where these strokes are occurring, depending both on region and whether people live in rural or urban settings. The investigation, which used data from the U.S. Department of Health and Human Services’ Agency for Healthcare Research and Quality (AHRQ), was reviewed by five stroke experts and found that the West and Midwest have seen especially worrisome increases among younger adults. Moreover, large cities appear to have seen bigger increases than rural areas. The analysis employed hospital discharge data from 2003 to 2012 from the AHRQ’s Healthcare Cost and Utilization Project (HCUP) database. The findings align with earlier studies that pointed to nationwide increases in strokes in this age group: In a study published earlier this year in JAMA Neurology, researchers at the U.S. Centers for Disease Control and Prevention concluded that in a nine-year span from 2003 to 2012 there was a 32 percent spike in strokes among 18- to 34-year-old women and a 15 percent increase for men in the same range. Scientific American’s analysis sought to dig deeper into the data by exploring whether the stroke trend differed by location. © 2017 Scientific American

Keyword: Stroke
Link ID: 23788 - Posted: 06.29.2017

Kerin Higa After surgery to treat her epilepsy severed the connection between the two halves of her brain, Karen's left hand took on a mind of its own, acting against her will to undress or even to slap her. Amazing, to be sure. But what may be even more amazing is that most people who have split-brain surgery don't notice anything different at all. But there's more to the story than that. In the 1960s, a young neuroscientist named Michael Gazzaniga began a series of experiments with split-brain patients that would change our understanding of the human brain forever. Working in the lab of Roger Sperry, who later won a Nobel Prize for his work, Gazzaniga discovered that the two halves of the brain experience the world quite differently. When Gazzaniga and his colleagues flashed a picture in front of a patient's right eye, the information was processed in the left side of the brain and the split-brain patient could easily describe the scene verbally. But when a picture was flashed in front of the left eye, which connects to the right side of the brain, the patient would report seeing nothing. If allowed to respond nonverbally, however, the right brain could adeptly point at or draw what was seen by the left eye. So the right brain knew what it was seeing; it just couldn't talk about it. These experiments showed for the first time that each brain hemisphere has specialized tasks. In this third episode of Invisibilia, hosts Alix Spiegel and Hanna Rosin talk to several people who are trying to change their other self, including a man who confronts his own biases and a woman who has a rare condition that causes one of her hands to take on a personality of its own. © 2017 npr

Keyword: Consciousness; Laterality
Link ID: 23749 - Posted: 06.17.2017