Chapter 16. None

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By MIKE IVES HONG KONG — President Rodrigo Duterte of the Philippines was elected in May after pledging to kill 100,000 criminals in his first six months in office, vowing that fish in Manila, the capital, would grow fat from eating the bodies of drug dealers and other “do nothings.” In Mr. Duterte’s first three months as president, his bloody campaign led to the killing of about 1,400 drug suspects by the police and hundreds of others by extrajudicial means, according to official estimates. He has also publicly accused thousands of government officials of being involved in the drug trade, in some cases offering no evidence. The campaign has taken particular aim at people who use or sell shabu, a cheap form of methamphetamine that has caused grave health and social problems across the country. Mr. Duterte has likened shabu addicts to zombies and claimed — absent evidence — that many are “no longer viable for rehabilitation” because abusing the drug shrinks their brains. What is methamphetamine? Methamphetamine is an addictive stimulant that can be made from ephedrine and other readily available chemicals. It typically comes in either tablets, called yaba in parts of Asia, or crystalline form. The first variety is common in mainland Southeast Asia, and the second — known as shabu, ice or crystal meth, among other names — is more popular in the Philippines and many other countries. It also tends to be more potent and more deeply intertwined with international drug manufacturing and smuggling networks, according to a report by the United Nations Office on Drugs and Crime. How does the drug affect people who use it? Smoking, snorting, ingesting or injecting methamphetamine can cause aggression, memory loss and a range of other health complications, including heart attack or sudden death. Links between methamphetamine abuse and crime, disease transmission and other social problems have also been documented. A study by the RAND Corporation found that the effects of methamphetamine abuse, including the burden of addiction and treatment, cost the United States $23.4 billion in 2005. © 2016 The New York Times Company

Keyword: Drug Abuse
Link ID: 22751 - Posted: 10.13.2016

By peering into the eyes of mice and tracking their ocular movements, researchers made an unexpected discovery: the visual cortex — a region of the brain known to process sensory information — plays a key role in promoting the plasticity of innate, spontaneous eye movements. The study, published in Nature, was led by researchers at the University of California, San Diego (UCSD) and the University of California, San Francisco (UCSF) and funded by the National Eye Institute (NEI), part of the National Institutes of Health. “This study elegantly shows how analysis of eye movement sheds more light on brain plasticity — an ability that is at the core of the brain’s capacity to adapt and function. More specifically, it shows how the visual cortex continues to surprise and to awe,” said Houmam Araj, Ph.D., a program director at NEI. Without our being aware of it, our eyes are in constant motion. As we rotate our heads and as the world around us moves, two ocular reflexes kick in to offset this movement and stabilize images projected onto our retinas, the light-sensitive tissue at the back of our eyes. The optokinetic reflex causes eyes to drift horizontally from side-to-side — for example, as we watch the scenery through a window of a moving train. The vestibulo-ocular reflex adjusts our eye position to offset head movements. Both reflexes are crucial to survival. These mechanisms allow us to see traffic while driving down a bumpy road, or a hawk in flight to see a mouse scurrying for cover.

Keyword: Vision
Link ID: 22750 - Posted: 10.13.2016

By Elizabeth Pennisi Although it has a face—and body—that only a mother could love, the naked mole rat has a lot to offer biomedical science. It lives 10 times longer than a mouse, almost never gets cancer, and doesn’t feel pain from injury and inflammation. Now, researchers say they’ve figured out how the rodents keep this pain away. “It’s an amazing result,” says Harold Zakon, an evolutionary neurobiologist at the University of Texas, Austin, who was not involved with the work. “This study points us to important areas … that might be targeted to reduce this type of pain.” Naked mole rats are just plain weird. They live almost totally underground in colonies structured like honey bee hives, with hundreds of workers servicing a single queen and her few consorts. To survive, they dig kilometers of tunnels in search of large underground tubers for food. It’s such a tough life that—to conserve energy—this member of the rodent family gave up regulating its temperature, and they are able to thrive in a low-oxygen, high–carbon dioxide environment that would suffocate or be very painful to humans. “They might as well be from another planet,” says Thomas Park, a neuroscientist at the University of Illinois, Chicago. Gary Lewin, a neuroscientist at the Max Delbrück Center for Molecular Medicine in the Helmholtz Association in Berlin, began working with naked mole rats because a friend in Chicago was finding that the rodent's pain fibers were not the same as other mammals'. In 2008, the studies led to the finding that naked mole rats didn’t feel pain when they came into contact with acid and didn’t get more sensitive to heat or touch when injured, like we and other mammals do. Lewin was hooked and has been raising the rodents in his lab ever since. They are a little more challenging than rats or mice, he notes, because with just one female per colony producing young, he never really has quite enough individuals for his studies. © 2016 American Association for the Advancement of Science

Keyword: Pain & Touch; Evolution
Link ID: 22749 - Posted: 10.12.2016

By Christian Jarrett It’s been said that men and women are so unlike each other, it’s as if they’re from different planets – a claim that continues to amuse and irritate. John Gray’s original mega-selling book Men are from Mars, Women are from Venus, first published in the early 1990s, has sold millions, spawning numerous parodies (such as Katherine Black and Finn Contini’s Women May Be from Venus, But Men are Really from Uranus) and even comedy stage shows, such as Men are from Mars, Women are from Venus, Live! currently playing off Broadway.) While our physical differences in size and anatomy are obvious, the question of psychological differences between the genders is a lot more complicated and controversial. There are issues around how to reliably measure the differences. And when psychologists find them, there are usually arguments over whether the causes are innate and biological, or social and cultural. Are men and women born different or does society shape them that way? These questions are particularly thorny when you consider our differences in personality. Most research suggests that men and women really do differ on some important traits. But are these differences the result of biology or cultural pressures? And just how meaningful are they in the real world? One possibility is that most differences are tiny in size but that combined they can have important consequences. One of the most influential studies in the field, published in 2001 by pioneering personality researchers Paul Costa, Robert McCrae and Antonio Terracciano, involved over 23,000 men and women from 26 cultures filling out personality questionnaires. © 2016 BBC.

Keyword: Sexual Behavior
Link ID: 22746 - Posted: 10.12.2016

By GRETCHEN REYNOLDS Exercise may aid in weight control and help to fend off diabetes by improving the ability of fat cells to burn calories, a new study reports. It may do this in part by boosting levels of a hormone called irisin, which is produced during exercise and which may help to turn ordinary white fat into much more metabolically active brown fat, the findings suggest. Irisin (named for the Greek goddess Iris) entered the scientific literature in 2012 after researchers from Harvard and other universities published a study in Nature that showed the previously unknown hormone was created in working muscles in mice. From there, it would enter the bloodstream and migrate to other tissues, particularly to fat, where it would jump-start a series of biochemical processes that caused some of the fat cells, normally white, to turn brown. Brown fat, which is actually brown in color, burns calories. It also is known to contribute to improved insulin and blood sugar control, lessening the risk for Type 2 diabetes. Most babies, including human infants, are plump with brown fat, but we humans lose most of our brown fat as we grow up. By the time we are adults, we usually retain very little brown fat. In the 2012 study, the researchers reported that if they injected irisin into living mice, it not only turned some white fat into brown fat, it apparently also prevented the rodents from becoming obese, even on a high-fat, high-calorie diet. But in the years since, some scientists have questioned whether irisin affects fat cells in people to the same extent as it seems to in mice — and even whether the hormone exists in people at all. A study published last year in Cell Metabolism by the same group of researchers who had conducted the first irisin study, however, does seem to have established that irisin is produced in humans. They found some irisin in sedentary people, but the levels were much higher in those who exercise often. © 2016 The New York Times Company

Keyword: Obesity
Link ID: 22744 - Posted: 10.12.2016

Allison Aubrey The World Health Organization has already urged us to cut back on sugar, limiting added sugars to no more than 10 percent of our daily calories. So, how might policymakers get people to follow this advice? In a new report, the WHO is urging governments around the world to tax soda and other sugary drinks. In its report, the World Health Organization points to systematic reviews of policies aimed at improving diet and preventing lifestyle diseases, such as obesity and diabetes. "The evidence was strongest and most consistent for the effectiveness of sugar-sweetened beverage taxes in the range of 20-50% in reducing consumption," the WHO's meta-review concludes. Dr. Douglas Bettcher, director of the WHO's Department for the Prevention of Noncommunicable Diseases, says that "consumption of free sugars, including products like sugary drinks, is a major factor in the global increase of people suffering from obesity and diabetes." "If governments tax products like sugary drinks, they can reduce suffering and save lives. They can also cut healthcare costs and increase revenues to invest in health services," Bettcher was quoted as saying in a WHO release on the report. The International Council of Beverages Associations, which represents soda companies and other beverage-makers around the globe, says it's disappointed with the new WHO report. "We strongly disagree with the committee's recommendation to tax beverages, as it is an unproven idea that has not been shown to improve public health based on global experiences to date," an ICBA release concludes. © 2016 npr

Keyword: Obesity
Link ID: 22743 - Posted: 10.12.2016

By JAN HOFFMAN Our daily tug of leash war goes like this. I tell Chico we’re taking a left. He yanks right, wet black nostrils burrowing in loamy leaf piles. Me versus a 15-pound Havanese, incensed by scent. Today, I let him win. That’s because I have fresh appreciation for his sniffing behavior, after reading a new book, “Being a Dog: Following the Dog into a World of Smell,” by Alexandra Horowitz, a professor of cognitive science who runs the Dog Cognition Lab at Barnard College. In it, she explains the elegant engineering of the dog’s olfactory system and how familiar canine behaviors — licking, sneezing, tail-wagging — have associations with smell. Dr. Horowitz also describes how she trained herself to enhance her inferior human sniffing ability. On a recent afternoon at Riverside Park in Manhattan, I met Dr. Horowitz and Finn (short for Finnegan), her affable, glossy black 9-year-old mixed breed. There she — and he — shared some sniffing insights that have since made my walks with Chico more intriguing and fun. “There are many ways to sniff, and the human method is not the best,” Dr. Horowitz said. Sniff researchers (yes, you read that correctly) have found we have about six million olfactory receptors; dogs have 300 million. Humans sniff once per second-and-a-half; dogs, five to 10 times a second. “They even exhale better than we do,” Dr. Horowitz continued, describing a sort of doggy yoga breath. Dogs exhale through the side slits of their nostrils, so they keep a continuous flow of inhaled air in their snout for smelling. “This gives them a continuous olfactory view of the world.” © 2016 The New York Times Company

Keyword: Chemical Senses (Smell & Taste)
Link ID: 22742 - Posted: 10.11.2016

By Daisy Yuhas About 350 million people around the world suffer from depression. Therapists can use many different techniques to help, but none has more rigorous scientific evidence behind it than cognitive-behavioral therapy (CBT). This “inside-out” technique focuses primarily on thought patterns, training patients to recognize and reframe problematic thinking. Now, however, mental health professionals have another option: mounting evidence shows that a technique called behavioral-activation (BA) therapy is just as effective as CBT. BA is an outside-in technique in which therapists focus on modifying actions rather than thoughts. “The idea is that what you do and how you feel are linked,” says David Richards, a health services researcher at the University of Exeter in England. If a patient values nature and family, for example, a therapist might encourage him to schedule a daily walk in the park with his grandchildren. Doing so could increase the rewards of engaging more with the outside world, which can be a struggle for depressed people, and could create an alternative to more negative pastimes such as ruminating on loss. BA has existed for decades, and some of its elements are used in CBT, yet until now it had never been tested with the scale and rigor needed to assess its relative strength as a stand-alone approach. In one of the largest studies of its kind, Richards led a collaboration of 18 researchers working at three mental health centers in the U.K. who put BA and CBT head-to-head. They assigned 440 people with depression to about 16 weeks of one of the two approaches, then followed the patients' progress at six, 12 and 18 months after treatment began. As revealed in a paper, published online in July in the Lancet, the team found the treatments to be equally effective. A year on, about two thirds of the patients in both groups reported at least a 50 percent reduction in their symptoms. © 2016 Scientific American

Keyword: Depression
Link ID: 22741 - Posted: 10.11.2016

By Clare Wilson Glug glug glug. I’m drinking a big glass of ice water after getting thirsty, and it’s flowing easily down my throat like a river. But a study of thirsty and well hydrated people suggests this isn’t always the case. We rarely pay attention to the business of swallowing, but it may play a subtle role in controlling our fluid intake, on top of our conscious feelings of thirst. If we are dehydrated, swallowing is effortless; if we are overhydrated, swallowing feels more difficult, putting us off drinking, according to a study by Michael Farrell at Monash University in Melbourne, Australia, and his team. “Normally it’s something we are not really conscious of – away it goes,” says Farrell. But when his team asked volunteers to rate the sensation of taking a small sip of water, they found that people who had recently drunk a lot of water said it took much more effort to swallow than those who were mildly hydrated – their difficult ratings rose from one out of ten to nearly five. Is eight really great? When people were overhydrated, brain scans showed that swallowing was linked with more activity in certain regions of the brain, including the prefrontal cortex, which is responsible for conscious thought processes. “It suggests a mechanism for inhibition of drinking that we don’t usually think about,” says Zachary Knight at the University of California, San Francisco. © Copyright Reed Business Information Ltd.

Keyword: Miscellaneous
Link ID: 22739 - Posted: 10.11.2016

Dean Burnett Throughout history, people have always worried about new technologies. The fear that the human brain cannot cope with the onslaught of information made possible by the latest development was first voiced in response to the printing press, back in the sixteenth century. Swap “printing press” for “internet” and you have the exact same concerns today, regularly voiced in the mainstream media, and usually focused on children. But is there any legitimacy to these claims? Or are they just needless scaremongering? There are several things to bear in mind when considering how our brains deal with the internet. The human brain is always dealing with a constant stream of rich information - that’s what the real world is First, don’t forget that “the internet” is a very vague term, given that it contains so many things across so many formats. You could, for instance, develop a gambling addiction via online casinos or poker sites. This is an example of someone’s brain being negatively affected via the internet, but it would be difficult to argue that the internet is the main culprit, any more than a gambling addiction obtained via a real world casino can be blamed on “buildings”; it’s just the context in which the problem occurred. However, the internet does give us a far more direct, constant and wide ranging access to information than pretty much anything else in human history. So how could, or does, this affect us and our brains? © 2016 Guardian News and Media Limited

Keyword: Learning & Memory
Link ID: 22736 - Posted: 10.10.2016

By Anna Azvolinsky _The human cerebral cortex experiences a burst of growth late in fetal development thanks to the expansion and migration of progenitor cells that ultimately form excitatory neurons. For a fully functional brain, in addition to excitatory neurons, inhibitory ones (called interneurons) are also necessary. Yet scientists have not been able to account for the increase in inhibitory neurons that occurs after birth. Now, in a paper published today (October 6) in Science, researchers from the University of California, San Francisco (UCSF), have shown that there is a reserve of young neurons that continue to migrate and integrate into the frontal lobes of infants. “It was thought previously that addition of new neurons to the human cortex [mostly] happens only during fetal development. This new study shows that young neurons continue to migrate on a large scale into the cerebral cortex of infants,” Benedikt Berninger, who studies brain development at the Johannes Gutenberg University of Mainz, Germany, and was not involved in the work, wrote in an email to The Scientist. “This implies that experience during the first few months could affect this migration and thereby contribute to brain plasticity.” Aside from the migration of neurons into the olfactory bulb in infants, “this is the first time anyone has been able to catch neurons in the act of moving into the cortex,” said New York University neuroscientist Gord Fishell who penned an accompanying editorial but was not involved in the work. “We kept expecting these interneurons to be new cells but, in fact, they are immature ones hanging around and taking the long road from the bottom of the brain to the cortex.” © 1986-2016 The Scientist

Keyword: Development of the Brain; Neurogenesis
Link ID: 22734 - Posted: 10.08.2016

Bruce Bower Apes understand what others believe to be true. What’s more, they realize that those beliefs can be wrong, researchers say. To make this discovery, researchers devised experiments involving a concealed, gorilla-suited person or a squirreled-away rock that had been moved from their original hiding places — something the apes knew, but a person looking for King Kong or the stone didn’t. “Apes anticipated that an individual would search for an object where he last saw it, even though the apes knew that the object was no longer there,” says evolutionary anthropologist Christopher Krupenye. If this first-of-its-kind finding holds up, it means that chimpanzees, bonobos and orangutans can understand that others’ actions sometimes reflect mistaken assumptions about reality. Apes’ grasp of others’ false beliefs roughly equals that of human 2-year-olds tested in much the same way, say Krupenye of the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, and his colleagues. Considering their targeted gazes during brief experiments, apes must rapidly assess others’ beliefs about the world in wild and captive communities, the researchers propose in the October 7 Science. Understanding the concept of false beliefs helps wild and captive chimps deceive their comrades, such as hiding food from those who don’t share, Krupenye suggests. |© Society for Science & the Public 2000 - 2016.

Keyword: Intelligence; Evolution
Link ID: 22733 - Posted: 10.08.2016

In his memoir Do No Harm, Henry Marsh confesses to the uncertainties he's dealt with as a surgeon and reflects on the enigmas of the brain and consciousness. Originally broadcast May 26, 2015. DAVE DAVIES, HOST: This is FRESH AIR. I'm Dave Davies, sitting in for Terry Gross. Our guest has opened heads and cut into brains, performing delicate and risky surgery on the part of the body that controls everything - breathing, movement, memory, and consciousness. In his work as a neurosurgeon, Dr. Henry Marsh has fixed aneurysms and spinal problems and spent many years operating on brain tumors. In his memoir, Dr. Marsh discusses some of his most challenging cases, triumphs and failures and confesses to the fears and uncertainties he's dealt with. He explains the surgical instruments he uses and how procedures have changed since he started practicing. And he reflects on the state of his profession and the mysteries of the brain and consciousness. Last year, he retired as the senior consulting neurosurgeon at St. George's Hospital in London, where he practiced for 28 years. He was the subject of the Emmy Award-winning 2007 documentary "The English Surgeon," which followed him in Ukraine, trying to help patients and improve conditions at a rundown hospital. Marsh's book, "Do No Harm," is now out in paperback. Terry spoke to him when it was published in hardback. © 2016 npr

Keyword: Consciousness
Link ID: 22732 - Posted: 10.08.2016

Emily Badger One of the newest chew toys in the presidential campaign is “implicit bias,” a term Mike Pence repeatedly took exception to in the vice-presidential debate on Tuesday. Police officers hear all this badmouthing, said Mr. Pence, Donald J. Trump’s running mate, in response to a question about whether society demands too much of law enforcement. They hear politicians painting them with one broad brush, with disdain, with automatic cries of implicit bias. He criticized Hillary Clinton for saying, in the first presidential debate, that everyone experiences implicit bias. He suggested a black police officer who shoots a black civilian could not logically experience such bias. “Senator, please,” Mr. Pence said, addressing his Democratic opponent, Tim Kaine, “enough of this seeking every opportunity to demean law enforcement broadly by making the accusation of implicit bias every time tragedy occurs.” The concept, in his words, came across as an insult, a put-down on par with branding police as racists. Many Americans may hear it as academic code for “racist.” But that connotation does not line up with scientific research on what implicit bias is and how it really operates. Researchers in this growing field say it isn’t just white police officers, but all of us, who have biases that are subconscious, hidden even to ourselves. Implicit bias is the mind’s way of making uncontrolled and automatic associations between two concepts very quickly. In many forms, implicit bias is a healthy human adaptation — it’s among the mental tools that help you mindlessly navigate your commute each morning. It crops up in contexts far beyond policing and race (if you make the rote assumption that fruit stands have fresher produce, that’s implicit bias). But the same process can also take the form of unconsciously associating certain identities, like African-American, with undesirable attributes, like violence. © 2016 The New York Times Company

Keyword: Attention
Link ID: 22730 - Posted: 10.08.2016

/ By Seth Mnookin When Henry Molaison died at a Connecticut nursing home in 2008, at the age of 82, a front-page obituary in The New York Times called him “the most important patient in the history of brain science.” It was no exaggeration: Much of what we know about how memory works is derived from experiments on Molaison, a patient with severe epilepsy who in 1953 had undergone an operation that left him without medial temporal lobes and the ability to form new memories. The operation didn’t completely stop Molaison’s seizures — the surgeon, William Beecher Scoville, had done little more than guess at the locus of his affliction — but by chance, it rendered him a near-perfect research subject. Not only could postoperative changes in his behavior be attributed to the precise area of his brain that had been removed, but the fact that he couldn’t remember what had happened 30 seconds earlier made him endlessly patient and eternally willing to endure all manner of experiments. It didn’t take long for those experiments to upend our understanding of the human brain. By the mid-1950s, studies on Molaison (known until his death only as Patient H.M.) had shown that, contrary to popular belief, memories were created not in the brain as a whole, but in specific regions — and that different types of memories were formed in different ways. Molaison remained a research subject until his death, and for the last 41 years of his life, the person who controlled access to him, and was involved in virtually all the research on him, was an MIT neuroscientist named Suzanne Corkin. Copyright 2016 Undark

Keyword: Learning & Memory
Link ID: 22729 - Posted: 10.05.2016

Jon Hamilton Want to be smarter? More focused? Free of memory problems as you age? If so, don't count on brain games to help you. That's the conclusion of an exhaustive evaluation of the scientific literature on brain training games and programs. It was published Monday in the journal Psychological Science in the Public Interest. "It's disappointing that the evidence isn't stronger," says Daniel Simons, an author of the article and a psychology professor at the University of Illinois at Urbana-Champaign. "It would be really nice if you could play some games and have it radically change your cognitive abilities," Simons says. "But the studies don't show that on objectively measured real-world outcomes." The evaluation, done by a team of seven scientists, is a response to a very public disagreement about the effectiveness of brain games, Simons says. In October 2014, more than 70 scientists published an open letter objecting to marketing claims made by brain training companies. Pretty soon, another group, with more than 100 scientists, published a rebuttal saying brain training has a solid scientific base. "So you had two consensus statements, each signed by many, many people, that came to essentially opposite conclusions," Simons says. © 2016 npr

Keyword: Learning & Memory
Link ID: 22727 - Posted: 10.05.2016

Joe Palca Most of us have been tempted at one time or another by the lure of sugar. Think of all the cakes and cookies you consume between Thanksgiving and Christmastime! But why are some people unable to resist that second cupcake or slice of pie? That's the question driving the research of Monica Dus, a molecular biologist at the University of Michigan. She wants to understand how excess sugar leads to obesity by understanding the effect of sugar on the brain. Dus's interest in how animals control the amount they eat started with a curious incident involving her two Bichon Frise dogs. One day, Cupcake and Sprinkles got into a bag of dog treats when Dus wasn't around. The dogs overdid it. "I couldn't believe that these two tiny, 15-pound animals had huge bellies for three days and they couldn't stop themselves from eating," she recalls. Dus was already an expert in fruit fly genetics, so she decided to study flies to see if she could unravel the puzzle of how the brain controls eating behavior. Her lab has a working hypothesis. Dus believes a diet high in sugar actually changes the brain, so it no longer does a good job of knowing how many calories the body is taking in. She thinks there are persistent molecular changes in the brain over time – changes that pave the way for excessive eating and eventually, obesity. Monica Dus is a researcher at the University of Michigan. She just won a $1.5 million Young Innovator grant from the National Institutes of Health to study how a high-sugar diet may lead to obesity by changing brain chemistry. © 2016 npr

Keyword: Obesity
Link ID: 22725 - Posted: 10.05.2016

Urine could potentially be used for a quick and simple way to test for CJD or "human mad cow disease", say scientists in the journal JAMA Neurology. The Medical Research Council team say their prototype test still needs honing before it could be used routinely. Currently there is no easy test available for this rare but fatal brain condition. Instead, doctors have to take a sample of spinal fluid or brain tissue, or wait for a post-mortem after death. What they look for is tell-tale deposits of abnormal proteins called prions, which cause the brain damage. Building on earlier US work, Dr Graham Jackson and colleagues, from University College London, have now found it is also possible to detect prions in urine. This might offer a way to diagnose CJD rapidly and earlier, they say, although there is no cure. Creutzfeldt-Jakob disease (CJD): CJD is a rare, but fatal degenerative brain disorder caused by abnormal proteins called prions that damage brain cells. There are several forms of the disease: sporadic, which occurs naturally in the human population, and accounts for 85% of all CJD cases variant CJD, linked to eating beef infected by bovine spongiform encephalopathy (BSE) iatrogenic infection, caused by contamination during medical or surgical treatment In the 1990s it became clear that a brain disease could be passed from cows to humans. The British government introduced a ban on beef on the bone. Since then, officials have kept a close check on how many people have become sick or died from CJD. © 2016 BBC

Keyword: Prions
Link ID: 22724 - Posted: 10.05.2016

By Emily Underwood When you let forth a big, embarrassing yawn during a boring lecture or concert, you succumb to a reflex so universal among animals that Charles Darwin mentioned it in his field notes. “Seeing a dog & horse & man yawn, makes me feel how much all animals are built on one structure,” he wrote in 1838. Scientists, however, still don’t agree on why we yawn or where it came from. So in a new study, researchers watched YouTube videos of 29 different yawning mammals, including mice, kittens, foxes, hedgehogs, walruses, elephants, and humans. (Here is a particularly cute montage used in the study.) They discovered a pattern: Small-brained animals with fewer neurons in the wrinkly outer layer of the brain, called the cortex, had shorter yawns than large-brained animals with more cortical neurons, the scientists report today in Biology Letters. Primates tended to yawn longer than nonprimates, and humans, with about 12,000 million cortical neurons, had the longest average yawn, lasting a little more than 6 seconds. African elephants, whose brains are close to the same weight as humans’ and have a similar number of cortical neurons, lasted about 6 seconds. The yawns of tiny-brained mice, in contrast, were less than 1.5 seconds in duration. The study lends support to a long-held hypothesis that yawning has an important physiological effect, such as increasing blood flood to the brain and cooling it down, the scientists say. © 2016 American Association for the Advancement of Science.

Keyword: Evolution; Emotions
Link ID: 22723 - Posted: 10.05.2016

By Rebecca Robbins, In the months before his death, Robin Williams was besieged by paranoia and so confused he couldn’t remember his lines while filming a movie, as his brain was ambushed by what doctors later identified as an unusually severe case of Lewy body dementia. “Robin was losing his mind and he was aware of it. Can you imagine the pain he felt as he experienced himself disintegrating?” the actor’s widow, Susan Schneider Williams, wrote in a wrenching editorial published this week in the journal Neurology. The title of her piece: “The terrorist inside my husband’s brain.” Susan Williams addressed the editorial to neurologists, writing that she hoped husband’s story would “help you understand your patients along with their spouses and caregivers a little more.” Susan Williams has previously blamed Lewy body dementia for her husband’s death by suicide in 2014. About 1.3 million Americans have the disease, which is caused by protein deposits in the brain. Williams was diagnosed with Parkinson’s disease a few months before he died; the telltale signs of Lewy body dementia in his brain were not discovered until an autopsy. The editorial chronicles Williams’s desperation as he sought to understand a bewildering array of symptoms that started with insomnia, constipation, and an impaired sense of smell and soon spiraled into extreme anxiety, tremors, and difficulty reasoning. © 2016 Scientific American,

Keyword: Alzheimers
Link ID: 22721 - Posted: 10.02.2016