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Few genes have made the headlines as much as FOXP2. The first gene associated with language disorders , it was later implicated in the evolution of human speech. Girls make more of the FOXP2 protein, which may help explain their precociousness in learning to talk. Now, neuroscientists have figured out how one of its molecular partners helps Foxp2 exert its effects.
The findings may eventually lead to new therapies for inherited speech disorders, says Richard Huganir, the neurobiologist at Johns Hopkins University School of Medicine in Baltimore, Maryland, who led the work. Foxp2 controls the activity of a gene called Srpx2, he notes, which helps some of the brain's nerve cells beef up their connections to other nerve cells. By establishing what SRPX2 does, researchers can look for defective copies of it in people suffering from problems talking or learning to talk.
Until 2001, scientists were not sure how genes influenced language. Then Simon Fisher, a neurogeneticist now at the Max Planck Institute for Psycholinguistics in Nijmegen, the Netherlands, and his colleagues fingered FOXP2 as the culprit in a family with several members who had trouble with pronunciation, putting words together, and understanding speech. These people cannot move their tongue and lips precisely enough to talk clearly, so even family members often can?t figure out what they are saying. It “opened a molecular window on the neural basis of speech and language,” Fisher says.
Photo credit: Yoichi Araki, Ph.D.
By Michael Price The titular detective of the BBC television series Sherlock possesses a “mind palace”—a highly organized mental catalog of nearly every memory he’s ever had. We mere mortals can’t match Holmes’s remarkable recollection, but when we store and recall memories, our brain activity probably looks a lot like his, according to a new study. The findings might help us find early warning signs of memory loss in diseases like Alzheimer’s. Previous research has found that when people perceive an event for the first time and when they are asked to remember it later, the same brain regions are activated. But whether different people encode the same memory in the same way has been a topic of debate. So scientists turned to Sherlock Holmes for answers. A group led by Janice Chen, a postdoc in the psychology department at Princeton University, and Yuan Chang Leong, a graduate student studying psychology at Stanford University in Palo Alto, California, strapped 22 study participants into a functional magnetic resonance imaging (fMRI) machine, which traces blood flow in the brain to measure brain activity. The scientists then showed them a 48-minute segment of BBC’s Sherlock. (Roughly the first half of the series’s first episode, “A Study in Pink,” for the curious superfans.) Immediately afterward, Chen asked the volunteers to tell her as much about the episode as they could. © 2016 American Association for the Advancement of Science.
Keyword: Learning & Memory
Link ID: 22956 - Posted: 12.06.2016
By CHRISTOPHER MELE Have you called your daughter by your wife’s name or your son by his brother’s name? Have you misplaced your car keys or forgotten where you parked at the mall? If you worry these might be signs of significant memory loss or the early stages of Alzheimer’s disease, which causes a slow deterioration in memory and reasoning skills, fear not, experts said. By the age of 45, the average person experiences a decline in memory, Dr. Gary W. Small, a professor of psychiatry and biobehavioral sciences at the David Geffen School of Medicine at the University of California, Los Angeles, said in an email. Forgetting facts or events over time, absent-mindedness and incorrectly recalling a detail are among six “normal” memory problems that should not cause concern, according to the Center for Brain-Mind Medicine at Brigham and Women’s Hospital in Boston. When people do experience normal memory decline related to aging, 85 percent of their complaints involve recalling people’s names, Dr. Small said. You can blame multitasking for overloading your mind. Think about the ways we are driven to distraction with smartphones and social media, for instance. “Whenever our brains are taxed by multiple demands, cognitive ‘slips’ or errors are more likely to occur due to a concept called memory ‘interference,’ ” Carrington Wendell, a neuropsychology specialist at the Anne Arundel Medical Group in Annapolis, Md., said in an email. Name mix-ups are also more likely to occur when the two names share the same beginning, middle or ending, such as Bob and Ben or Dave and Jake, and are the same sex and similar age, she added. © 2016 The New York Times Company
People who consistently smoked an average of less than one cigarette per day over their lifetime had a 64 percent higher risk of earlier death than never smokers, and those who smoked between one and 10 cigarettes a day had an 87 percent higher risk of earlier death than never smokers, according to a new study from researchers at the National Cancer Institute (NCI). Risks were lower among former low-intensity smokers compared to those who were still smokers, and risk fell with earlier age at quitting. The results of the study were reported Dec. 5, 2016, in JAMA Internal Medicine. NCI is part of the National Institutes of Health. When researchers looked at specific causes of death among study participants, a particularly strong association was observed for lung cancer mortality. Those who consistently averaged less than one cigarette per day over their lifetime had nine times the risk of dying from lung cancer than never smokers. Among people who smoked between one and 10 cigarettes per day, the risk of dying from lung cancer was nearly 12 times higher than that of never smokers. The researchers looked at risk of death from respiratory disease, such as emphysema, as well as the risk of death from cardiovascular disease. People who smoked between one and 10 cigarettes a day had over six times the risk of dying from respiratory diseases than never smokers and about one and half times the risk of dying of cardiovascular disease than never smokers. Smoking has many harmful effects on health, which have been detailed in numerous studies since the U.S. Surgeon General’s 1964 report linking smoking to lung cancer. The health effects of consistent low-intensity smoking, however, have not been well studied and many smokers believe that low-intensity smoking does not affect their health.
Keyword: Drug Abuse
Link ID: 22954 - Posted: 12.06.2016
By CATHERINE SAINT LOUIS These days, even 3-year-olds wear headphones, and as the holidays approach, retailers are well stocked with brands that claim to be “safe for young ears” or to deliver “100 percent safe listening.” The devices limit the volume at which sound can be played; parents rely on them to prevent children from blasting, say, Rihanna at hazardous levels that could lead to hearing loss. But a new analysis by The Wirecutter, a product recommendations website owned by The New York Times, has found that half of 30 sets of children’s headphones tested did not restrict volume to the promised limit. The worst headphones produced sound so loud that it could be hazardous to ears in minutes. “These are terribly important findings,” said Cory Portnuff, a pediatric audiologist at the University of Colorado Hospital, who was not involved in the analysis. “Manufacturers are making claims that aren’t accurate.” The new analysis should be a wake-up call to parents who thought volume-limiting technology offered adequate protection, said Dr. Blake Papsin, the chief otolaryngologist at the Hospital for Sick Children in Toronto. “Headphone manufacturers aren’t interested in the health of your child’s ears,” he said. “They are interested in selling products, and some of them are not good for you.” Half of 8- to 12-year-olds listen to music daily, and nearly two-thirds of teenagers do, according to a 2015 report with more than 2,600 participants. Safe listening is a function of both volume and duration: The louder a sound, the less time you should listen to it. It’s not a linear relationship. Eighty decibels is twice as loud as 70 decibels, and 90 decibels is four times louder. Exposure to 100 decibels, about the volume of noise caused by a power lawn mower, is safe for just 15 minutes; noise at 108 decibels, however, is safe for less than three minutes. © 2016 The New York Times Company
Link ID: 22953 - Posted: 12.06.2016
Emily Conover A bird in laser goggles has helped scientists discover a new phenomenon in the physics of flight. Swirling vortices appear in the flow of air that follows a bird’s wingbeat. But for slowly flying birds, these vortices were unexpectedly short-lived, researchers from Stanford University report December 6 in Bioinspiration and Biomimetics. The results could help scientists better understand how animals fly, and could be important for designing flying robots (SN: 2/7/15, p. 18). To study the complex air currents produced by birds’ flapping wings, the researchers trained a Pacific parrotlet, a small species of parrot, to fly through laser light — with the appropriate eye protection, of course. Study coauthor Eric Gutierrez, who recently graduated from Stanford, built tiny, 3-D‒printed laser goggles for the bird, named Obi. Gutierrez and colleagues tracked the air currents left in Obi’s wake by spraying a fine liquid mist in the air, and illuminating it with a laser spread out into a two-dimensional sheet. High-speed cameras recorded the action at 1,000 frames per second. The vortex produced by the bird “explosively breaks up,” says mechanical engineer David Lentink, a coauthor of the study. “The flow becomes very complex, much more turbulent.” Comparing three standard methods for calculating the lift produced by flapping wings showed that predictions didn’t match reality, thanks to the unexpected vortex breakup. |© Society for Science & the Public 2000 - 20
Link ID: 22952 - Posted: 12.06.2016
By PETER GODFREY-SMITH Around 2008, while snorkeling and scuba diving in my free time, I began watching the unusual group of animals known as cephalopods, the group that includes octopuses, cuttlefish and squid. The first ones I encountered were giant cuttlefish, large animals whose skin changes color so quickly and completely that swimming after them can be like following an aquatic, multi-armed television. Then I began watching octopuses. Despite being mollusks, like clams and oysters, these animals have very large brains and exhibit a curious, enigmatic intelligence. I followed them through the sea, and also began reading about them, and one of the first things I learned came as a shock: They have extremely short lives — just one or two years. I was already puzzled by the evolution of large brains in cephalopods, and this discovery made the questions more acute. What is the point of building a complex brain like that if your life is over in a year or two? Why invest in a process of learning about the world if there is no time to put that information to use? An octopus’s or cuttlefish’s life is rich in experience, but it is incredibly compressed. The particular puzzle of octopus life span opens up a more general one. Why do animals age? And why do they age so differently? A scruffy-looking fish that inhabits the same patch of sea as my cephalopods has relatives who live to 200 years of age. This seems extraordinarily unfair: A dull-looking fish lives for centuries while the cuttlefish, in their chromatic splendor, and the octopuses, in their inquisitive intelligence, are dead before they are 2? There are monkeys the size of a mouse that can live for 15 years, and hummingbirds that can live for over 10. Nautiluses (who are also cephalopods) can live for 20 years. A recent Nature paper reported that despite continuing medical advances, humans appear to have reached a rough plateau at around 115 years, though a few people will edge beyond it. The life spans of animals seem to lack all rhyme or reason. © 2016 The New York Times Company
By Israel Robledo As has often been said, with great power comes great responsibility. As we saw in the recent election, social media is a great example of a powerful medium that can change minds and change lives but can also give credibility to false or misguiding information. As someone diagnosed with Parkinson’s disease (PD) nine years ago, I’ve thrilled at seeing social media’s growing power as an agent for good. As our advocacy community has grown, social media has allowed for more information to be circulated in the PD community than ever before, and has become a vital link through which we share experiences, raise awareness about quality of life issues, point people to clinical trials, spread knowledge about cutting-edge research—and importantly, raise critical dollars to fund it. Connecting our community more tightly together has underscored the important role each of us can play in finding an eventual cure. A downside to the awesome power of this platform comes from not knowing or perhaps not caring about the source of information shared on social media. Just as “fake news” has flourished in an environment where speed, rather than accuracy, is what counts, patients—who are understandably vulnerable to hopeful reports about their disease—must recognize that not everything they read is equally credible. In my years of advocating for PD-related causes, hundreds of so-called “miracles” have been announced, all of which have proven to have disappointing results. © 2016 Scientific American
Link ID: 22950 - Posted: 12.05.2016
Gabrielle Emanuel Megan Lordos, a middle school teacher, says she was not allowed to use the word "dyslexia." She's not alone. Parents and teachers across the country have raised concerns about some schools hesitating, or completely refusing, to say the word. As the most common learning disability in the U.S., dyslexia affects somewhere between 5 and 17 percent of the population. That means millions of school children around the country struggle with it. Under the Individuals with Disabilities Education Act (IDEA), schools are required to provide special services to help these students — things like reading tutors and books on tape. But those special services can be expensive, and many schools don't have the resources to provide these accommodations. That has led some parents and advocates to worry that some schools are making a careful calculation: If they don't acknowledge the issue — or don't use the word "dyslexia" — then they are not obligated to provide services. Last year, when Lordos was teaching English at a public school in Arlington, Va., she recalls a parent-teacher meeting in the conference room. Things started smoothly. Lordos says two parents had come in to talk with teachers and administrators about their son – Lordos' student, an eighth-grader – who was struggling to read. Partway through the meeting, Lordos says she suggested that the student might have orthographic dyslexia. Two of Lordos' own children have dyslexia and, she says, she noticed her student had similar challenges to the ones she'd seen at home. © 2016 npr
Link ID: 22949 - Posted: 12.05.2016
By Alice Klein It’s something all whale-watchers yearn to see. The sight of whales breaking the surface and slapping their fins on the water is a true spectacle – but the animals don’t do it just for show. Instead, it appears that all that splashing is about messaging other whales, and the big splashes are for long-distance calls. Ailbhe Kavanagh at the University of Queensland in Gatton, Australia, and her colleagues studied 94 different groups of humpback whales migrating south along the Queensland coast in 2010 and 2011. Humpback whales regularly leap out of the water and twist on to their backs – an action known as breaching – and slap their tails and fins in a repetitive fashion. The resulting sounds travel underwater and could possibly communicate messages to other whales. Drowning in sound: The sad case of the baby beluga whales The team found evidence for this idea. The animals were significantly more likely to breach when the nearest other whale group was more than 4 kilometres away, suggesting that the body-slapping sound of breaching was used to signal to distant groups. In contrast, repetitive tail and pectoral-fin slapping appeared to be for close-range communication. There was a sudden increase in this behaviour just before new whales joined or the group split up. © Copyright Reed Business Information Ltd.
By Jessica Boddy Memory researchers have shone light into a cognitive limbo. A new memory—the name of someone you've just met, for example—is held for seconds in so-called working memory, as your brain's neurons continue to fire. If the person is important to you, the name will over a few days enter your long-term memory, preserved by permanently altered neural connections. But where does it go during the in-between hours, when it has left your standard working memory and is not yet embedded in long-term memory? In Science, a research team shows that memories can be resurrected from this limbo. Their observations point to a new form of working memory, which they dub prioritized long-term memory, that exists without elevated neural activity. Consistent with other recent work, the study suggests that information can somehow be held among the synapses that connect neurons, even after conventional working memory has faded. "This is a really fundamental find—it's like the dark matter of memory," says Geoffrey Woodman, a cognitive neuroscientist at Vanderbilt University in Nashville who was not involved with the work. "It's hard to really see it or measure it in any clear way, but it has to be out there. Otherwise, things would fly apart." Cognitive neuroscientist Nathan Rose and colleagues at the University of Wisconsin (UW) in Madison initially had subjects watch a series of slides showing faces, words, or dots moving in one direction. They tracked the resulting neural activity using functional magnetic resonance imaging (fMRI) and, with the help of a machine learning algorithm, showed they could classify the brain activity associated with each item. Then the subjects viewed the items in combination—a word and face, for example—but were cued to focus on just one item. At first, the brain signatures of both items showed up, as measured in this round with electroencephalography (EEG). But neural activity for the uncued item quickly dropped to baseline, as if it had been forgotten, whereas the EEG signature of the cued item remained, a sign that it was still in working memory. Yet subjects could still quickly recall the uncued item when prompted to remember it a few seconds later. © 2016 American Association for the Advancement of Science.
Keyword: Learning & Memory
Link ID: 22947 - Posted: 12.03.2016
Rosie Mestel The 2016 US election was a powerful reminder that beliefs tend to come in packages: socialized medicine is bad, gun ownership is a fundamental right, and climate change is a myth — or the other way around. Stances that may seem unrelated can cluster because they have become powerful symbols of membership of a group, says Dan Kahan, who teaches law and psychology at Yale Law School in New Haven, Connecticut. And the need to keep believing can further distort people’s perceptions and their evaluation of evidence. Here, Kahan tells Nature about the real-world consequences of group affinity and cognitive bias, and about research that may point to remedies. This interview has been edited for length and clarity. One measure is how individualistic or communitarian people are, and how egalitarian or hierarchical. Hierarchical and individualistic people tend to have confidence in markets and industry: those represent human ingenuity and power. People who are egalitarian and communitarian are suspicious of markets and industry. They see them as responsible for social disparity. It’s natural to see things you consider honourable as good for society, and things that are base, as bad. Such associations will motivate people’s assessment of evidence. Can you give an example? In a study, we showed people data from gun-control experiments and varied the results1. People who were high in numeracy always saw when a study supported their view. If it didn’t support their view, they didn’t notice — or argued their way out of it. © 2016 Macmillan Publishers Limited
Maanvi Singh "I lost more than 80 percent of my university friends," recalls Jagannath Lamichhane. After silently struggling with depression for two decades, Lamichhane published an essay in Nepal Times about his mental illness. "I could have hid my problem — like millions of people around the world," he says, but "if we hide our mental health, it may remain a problem forever." Many of his friends and family didn't agree with that logic. In Nepal — as in most parts of the world — there's quite a lot of stigma around mental illness. That was eight years ago. Now 35-year-old Lamichhane is a mental health advocate, working to challenge the stigma around depression. "People believe that depression is the result of personal weaknesses and the result of bad karma in a past life," he says. Even worse, they don't believe they can be helped, he says — so they don't seek treatment. The problem isn't unique to Lamichhane's community. An estimated 350 million people are affected by depression, and the vast majority of them don't get treatment for their condition either due to stigma or a lack of knowledge, according to a study of more than 50,000 people in 21 countries. The study was led by Graham Thornicroft, a professor of psychiatry at King's College London. He and his team of researchers from King's College London, Harvard Medical School and the World Health Organization found that in the poorest countries, one in 27 people with depression received minimally adequate care for their condition. Even in the richest countries, only one in five people with depression sought care. The data was published Thursday in The British Journal of Psychiatry. © 2016 npr
Link ID: 22945 - Posted: 12.03.2016
By Alison Howell What could once only be imagined in science fiction is now increasingly coming to fruition: Drones can be flown by human brains' thoughts. Pharmaceuticals can help soldiers forget traumatic experiences or produce feelings of trust to encourage confession in interrogation. DARPA-funded research is working on everything from implanting brain chips to "neural dust" in an effort to alleviate the effects of traumatic experience in war. Invisible microwave beams produced by military contractors and tested on U.S. prisoners can produce the sensation of burning at a distance. What all these techniques and technologies have in common is that they're recent neuroscientific breakthroughs propelled by military research within a broader context of rapid neuroscientific development, driven by massive government-funded projects in both America and the European Union. Even while much about the brain remains mysterious, this research has contributed to the rapid and startling development of neuroscientific technology. And while we might marvel at these developments, it is also undeniably true that this state of affairs raises significant ethical questions. What is the proper role – if any – of neuroscience in national defense or war efforts? My research addresses these questions in the broader context of looking at how international relations, and specifically warfare, are shaped by scientific and medical expertise and technology. 2016 © U.S. News & World Report L.P.
.By JOANNA KLEIN A honey bee gathering pollen on a white flower. Dagmar Sporck/EyeEm, via Getty Images Set your meetings, phone calls and emails aside, at least for the next several minutes. That’s because today you’re a bee. It's time to leave your hive, or your underground burrow, and forage for pollen. Pollen is the stuff that flowers use to reproduce. But it’s also essential grub for you, other bees in your hive and your larvae. Once you’ve gathered pollen to take home, you or another bee will mix it with water and flower nectar that other bees have gathered and stored in the hive. But how do you decide which flowers to approach? What draws you in? In a review published last week in the journal Functional Ecology, researchers asked: What is a flower like from a bee’s perspective, and what does the pollinator experience as it gathers pollen? And that's why we're talking to you in the second person: to help you understand how bees like you, while hunting for pollen, use all of your senses — taste, touch, smell and more — to decide what to pick up and bring home. Maybe you're ready to go find some pollen. But do you even know where to look? © 2016 The New York Times Company
Barbara J. King Birdsong is music to human ears. It has inspired famous composers. For the rest of us, it may uplift the spirit and improve attention or simply be a source of delight, fun and learning. But have you ever wondered what birds themselves hear when they sing? After all, we know that other animals' perceptions don't always match ours. Anyone who lives with a dog has probably experienced their incredible acute hearing and smell. Psychologists Robert J. Dooling and Nora H. Prior think they've found an answer to that question — for, at least, some birds. In an article published online last month in the journal Animal Behaviour, they conclude that "there is an acoustic richness in bird vocalizations that is available to birds but likely out of reach for human listeners." Dooling and Prior explain that most scientific investigations of birdsong focus on things like pitch, tempo, complexity, structural organization and the presence of stereotypy. They instead focused on what's called temporal fine structure and its perception by zebra finches. Temporal fine structure, they write, "is generally defined as rapid variations in amplitude within the more slowly varying envelope of sound." Struggling to fully grasp that definition, I contacted Robert Dooling by email. In his response, he suggested that I think of temporal fine structure as "roughly the difference between voices when they are the same pitch and loudness." Temporal fine structure is akin, then, to timbre, sometimes defined as "tone color" or, in Dooling's words, the feature that's "left between two complex sounds when the pitch and level are equalized." © 2016 npr
By Torah Kachur, A dog's nose is an incredible scent detector. This ability has been used to train bomb-sniffing dogs, narcotics and contraband sniffers as well as tracking hounds. But even the best electronic scent-detection devices — which use the dog's nose as their gold standard — have never been able to quite live up to their canine competition. But new research — which took a plastic dog nose and strapped it to a bomb sniffing device — might change that. The shape and function of a dog's nose is being used to improve electronic scent detectors. (Flickr / montillon.a) Dogs have almost 300 million smell receptors in their noses, compared to the meagre six million us humans have: their sense of smell is more than 40 times better than ours. But those smell receptors are just part of the puzzle. Matthew Staymates, lead author on a new paper published Thursday, figured that the canine sniffing skill also has something to do with the anatomy of a dog's nose. A former roommate of his had done his PhD in dog nose anatomy and actually had a computer model of a dog's nose and entire head. So Staymates used a 3D printer, printed out a dog's nose, and attached it to an electronic detector. "Sure enough, a week or two later, I had a fully functioning, anatomically correct dog's nose that sniffs like a real dog." From that, he worked with something called a schlieren imager to watch air go in and out of a nose when the dog is snuffling around the ground. ©2016 CBC/Radio-Canada.
Sarah Boseley Health editor A single dose of psilocybin, the active ingredient of magic mushrooms, can lift the anxiety and depression experienced by people with advanced cancer for six months or even longer, two new studies show. Researchers involved in the two trials in the United States say the results are remarkable. The volunteers had “profoundly meaningful and spiritual experiences” which made most of them rethink life and death, ended their despair and brought about lasting improvement in the quality of their lives. The results of the research are published in the Journal of Psychopharmacology together with no less than ten commentaries from leading scientists in the fields of psychiatry and palliative care, who all back further research. While the effects of magic mushrooms have been of interest to psychiatry since the 1950s, the classification of all psychedelics in the US as schedule 1 drugs in the 1970s, in the wake of the Vietnam war and the rise of recreational drug use in the hippy counter-culture, has erected daunting legal and financial obstacles to running trials. “I think it is a big deal both in terms of the findings and in terms of the history and what it represents. It was part of psychiatry and vanished and now it’s been brought back,” said Dr Stephen Ross, director of addiction psychiatry at NYU Langone Medical Center and lead investigator of the study that was based there. © 2016 Guardian News and Media Limited
By BENEDICT CAREY The same digital screens that have helped nurture a generation of insomniacs can also help restore regular sleep, researchers reported on Wednesday. In a new study, more than half of chronic insomniacs who used an automated online therapy program reported improvement within weeks and were sleeping normally a year later. The new report, published in the journal JAMA Psychiatry, is the most comprehensive to date suggesting that many garden-variety insomniacs could benefit from the gold standard treatment — cognitive behavior therapy — without ever having to talk to a therapist. At least one in 10 adults has diagnosable insomnia, which is defined as broken, irregular, inadequate slumber at least three nights a week for three months running or longer. “I’ve been an insomniac all my life, I’ve tried about everything,” said Dale Love-Callon, 70, a math tutor living in Rancho Palos Verdes, Calif., who recently used the software. “I don’t have it 100 percent conquered, but I’m sleeping much better now.” Previous studies have found that online sleep therapy can be effective, but most have been smaller, or focused on a particular sleep-related problem, like depression. The new trial tested the digital therapy in a broad, diverse group of longtime insomniacs whose main complaint was lack of sleep. Most had used medication or supplements over the years, and some still did. “These results suggest that there are a group of patients who can benefit without the need of a high-intensity intervention,” like face-to-face therapy, said Jack Edinger, a professor in the department of medicine at National Jewish Health in Denver, who was not a part of the study. “We don’t know yet exactly who they are — the people who volunteer for a study like this in first place are self-motivated — but they’re out there.” © 2016 The New York Times Company
Link ID: 22939 - Posted: 12.01.2016
By Clare Wilson WE HAVE been thinking about Parkinson’s disease all wrong. The condition may arise from damage to the gut, not the brain. If the idea is correct, it opens the door to new ways of treating the disease before symptoms occur. “That would be game-changing,” says David Burn at Newcastle University, UK. “There are lots of different mechanisms that could potentially stop the spread.” Parkinson’s disease involves the death of neurons deep within the brain, causing tremors, stiffness and difficulty moving. While there are drugs that ease these symptoms, they become less effective as the disease progresses. One of the hallmarks of the condition is deposits of insoluble fibres of a substance called synuclein. Normally found as small soluble molecules in healthy nerve cells, in people with Parkinson’s, something causes the synuclein molecules to warp into a different shape, making them clump together as fibres. The first clue that this transition may start outside the brain came about a decade ago, when pathologists reported seeing the distinctive synuclein fibres in nerves of the gut during autopsies – both in people with Parkinson’s and in those without symptoms but who had the fibres in their brain. They suggested the trigger was some unknown microbe or toxin. © Copyright Reed Business Information Ltd.
Link ID: 22938 - Posted: 12.01.2016
Amanda Gefter As we go about our daily lives, we tend to assume that our perceptions—sights, sounds, textures, tastes—are an accurate portrayal of the real world. Sure, when we stop and think about it—or when we find ourselves fooled by a perceptual illusion—we realize with a jolt that what we perceive is never the world directly, but rather our brain’s best guess at what that world is like, a kind of internal simulation of an external reality. Still, we bank on the fact that our simulation is a reasonably decent one. If it wasn’t, wouldn’t evolution have weeded us out by now? The true reality might be forever beyond our reach, but surely our senses give us at least an inkling of what it’s really like. Not so, says Donald D. Hoffman, a professor of cognitive science at the University of California, Irvine. Hoffman has spent the past three decades studying perception, artificial intelligence, evolutionary game theory and the brain, and his conclusion is a dramatic one: The world presented to us by our perceptions is nothing like reality. What’s more, he says, we have evolution itself to thank for this magnificent illusion, as it maximizes evolutionary fitness by driving truth to extinction. Getting at questions about the nature of reality, and disentangling the observer from the observed, is an endeavor that straddles the boundaries of neuroscience and fundamental physics. On one side you’ll find researchers scratching their chins raw trying to understand how a three-pound lump of gray matter obeying nothing more than the ordinary laws of physics can give rise to first-person conscious experience. This is the aptly named “hard problem.”
Link ID: 22937 - Posted: 12.01.2016