Abby Olena Researchers have shown previously that excessive proliferation of the cells of the brain, which can cause macrocephaly, or large head size, is associated with autism. Now, the authors of a study published in Cell Stem Cell last week (January 30) have connected that overgrowth with replication stress, subsequent DNA damage, and dysfunction in neural progenitor cells derived from induced pluripotent stem cells from patients with autism spectrum disorder. “It is striking,” Bjoern Schwer, a molecular biologist at the University of California, San Francisco, who studies DNA repair and genomic stability in neural cells and did not participate in the study, writes in an email to The Scientist. “These are fascinating findings with many implications for autism spectrum disorder—and potentially for other neurodevelopmental disorders too.” In 2016, a group led by Schwer and Frederick Alt of Boston Children’s Hospital showed that mice have clusters of double-strand DNA breaks in the genomes of their neural progenitor cells. These hotspots are concentrated in neural-specific genes, which tend to be longer than genes expressed in other cell types and have also been associated with neurological diseases. Rusty Gage, a neuroscientist at the Salk institute, Meiyan Wang, a graduate student in the Gage lab, and their colleagues collaborated with Alt to explore whether or not these same damaged clusters would show up in the genomes of human neural progenitor cells. Wang went to the Alt lab to learn how to map genome-wide double-strand breaks. Then, she used the technique on several neural progenitor cell lines that had been previously derived in the Gage lab: three from patients with macrocephalic autism spectrum disorder and three from neurotypical controls. © 1986–2020 The Scientist

Keyword: Autism; Genes & Behavior
Link ID: 27025 - Posted: 02.07.2020

By Bernardo Kastrup At least since the Enlightenment, in the 18th century, one of the most central questions of human existence has been whether we have free will. In the late 20th century, some thought neuroscience had settled the question. However, as it has recently become clear, such was not the case. The elusive answer is nonetheless foundational to our moral codes, criminal justice system, religions and even to the very meaning of life itself—for if every event of life is merely the predictable outcome of mechanical laws, one may question the point of it all. But before we ask ourselves whether we have free will, we must understand what exactly we mean by it. A common and straightforward view is that, if our choices are predetermined, then we don’t have free will; otherwise we do. Yet, upon more careful reflection, this view proves surprisingly inappropriate. To see why, notice first that the prefix “pre” in “predetermined choice” is entirely redundant. Not only are all predetermined choices determined by definition, all determined choices can be regarded as predetermined as well: they always result from dispositions or necessities that precede them. Therefore, what we are really asking is simply whether our choices are determined. In this context, a free-willed choice would be an undetermined one. But what is an undetermined choice? It can only be a random one, for anything that isn’t fundamentally random reflects some underlying disposition or necessity that determines it. There is no semantic space between determinism and randomness that could accommodate choices that are neither. This is a simple but important point, for we often think—incoherently—of free-willed choices as neither determined nor random. © 2020 Scientific American

Keyword: Consciousness
Link ID: 27024 - Posted: 02.07.2020

Sarah O’Meara Xiaoming Zhou is a neurobiologist at East China Normal University in Shanghai. Here he speaks to Nature about his research into age-related hearing loss, and explains why he hopes that brain training could help to lessen declines in sensory perception generally, and so ward off neurodegenerative diseases. What is your current research focus? We want to better understand the neural basis for why a person’s hearing function declines as they grow older. For example, we have performed research to see whether we can reverse age-related changes to the auditory systems of rodents. We gave the animals a set of tasks, such as learning to discriminate between sounds of different frequencies or intensities. These exercises caused the rodents’ hearing to improve, and also promoted changes to the hippocampus, a part of the brain structure closely associated with learning and memory. The relationship with the hippocampus suggests that new kinds of brain training might help to attenuate our declines in perception and other brain functions, such as learning and memory, as we grow older — and so have the potential to stave off neurodegenerative diseases. How is ageing-related science developing in China? As has happened in the rest of the world, a rapidly ageing population has brought significant concern to policymakers. However, as far as I know, only a few neuroscience laboratories in China are specifically focused on learning more about the underlying mechanisms that cause changes in brain function as we age. This is despite the fact that such research could have a considerable impact on the welfare of older people in the future. © 2020 Springer Nature Limited

Keyword: Alzheimers
Link ID: 27023 - Posted: 02.07.2020

By Laura Sanders Injecting a swarm of nanoparticles into the blood of someone who has suffered a brain injury may one day help to limit the damage — if experimental results in mice can be translated to humans. In mice, these nanoparticles seemed to reduce dangerous swelling by distracting immune cells from rushing to an injured brain. The results, described online January 10 in the Annals of Neurology, hint that the inflammation-fighting nanoparticles might someday make powerful medicine, says John Kessler, a neurologist at Northwestern Medicine in Chicago. “All the data we have now suggest that they’re going to be safe, and they’re likely to work” for people, Kessler says. “But we don’t know that yet.” After an injury, tissue often swells as immune cells flock to the damage. Swelling of the brain can be dangerous because the brain is contained within the skull and “there’s no place to go,” Kessler says. The resulting pressure can be deadly. But nanoparticles might serve as an immune-cell distraction, the results in mice suggest. Two to three hours after a head injury, mice received injections of tiny biodegradable particles made of an FDA-approved polymer — the same sort that’s used in some dissolving sutures. Instead of rushing toward the brain, a certain type of immune cell called monocytes began turning their sights on these invaders. These monocytes engulfed the nanoparticles, and the cells and their cargo got packed off to the spleen for elimination, the researchers found. Because these nanoparticles are quickly taken out of circulation, the researchers injected the mice again one and two days later, in an effort to ease inflammation that might crop back up in the days after the injury. © Society for Science & the Public 2000–2020

Keyword: Brain Injury/Concussion
Link ID: 27022 - Posted: 02.05.2020

By Charles Zanor We all know people who say they have “no sense of direction,” and our tendency is almost always to minimize such claims rather than take them at full force. Yet for some people that description is literally true, and true in all circumstances: If they take a single wrong turn on an established route they often become totally lost. This happens even when they are just a few miles from where they live. Ellen Rose had been a patient of mine for years before I realized that she had this life-long learning disability. Advertisement I was made aware of it not long after I moved my psychology office from Agawam, Massachusetts to Suffield, Connecticut, just five miles away. I gave Ellen a fresh set of directions from the Springfield, Massachusetts area that took her south on Interstate 91 to Exit 47W, then across the Connecticut River to Rte 159 in Suffield. I thought it would pose no problem at all for her. A few minutes past her scheduled appointment time she called to say that she was lost. She had come south on Route 91 and had taken the correct exit, but she got confused and almost immediately hooked a right onto a road going directly north, bringing her back over the Massachusetts line to the town of Longmeadow. She knew this was wrong but did not know how to correct it, so I repeated the directions to get on 91 South and so on. Minutes passed, and then more minutes passed, and she called again to say that somehow she had driven by the exit she was supposed to take and was in Windsor, Connecticut. I kept her on the phone and guided her turn by turn to my office. Advertisement When I asked her why she hadn’t taken Exit 47W, she said that she saw it but it came up sooner than she expected so she kept going. This condition—developmental topographic disorientation—didn’t even have a formal name until 2009, when Giuseppe Iaria reported his first case in the journal Neuropsychologia. To understand DTD it is best to begin by saying that there are two main ways that successful travelers use to navigate their environment. © 2020 Scientific American,

Keyword: Learning & Memory; Development of the Brain
Link ID: 27021 - Posted: 02.05.2020

By Kelly Servick Since its launch in 2013, the Brain Research through Advancing Innovative Neurotechnologies (BRAIN) Initiative has doled out about $1.3 billion in grants to develop tools that map and manipulate the brain. Until now, it has operated with no formal director. But last week, the National Institutes of Health (NIH), which manages the initiative and is a key funder, announced that neurobiologist John Ngai would take the helm starting in March. Ngai, whose lab at the University of California, Berkeley, focuses on the neural underpinnings of the sense of smell, has helped lead BRAIN-funded efforts to classify the brain’s dizzying array of cell types with RNA sequencing. Ngai told ScienceInsider about how the initiative is evolving and how he hopes to influence it. The interview has been edited for clarity and brevity. Q: Why is the BRAIN Initiative getting a director now? A: The initiative has been run day to day by a terrific team of senior program directors and staff with oversight from the 10 NIH institutes and centers that are involved in BRAIN. Walter Koroshetz [director of the National Institute of Neurological Disorders and Stroke] and Josh Gordon [director of the National Institute of Mental Health] have been overseeing the activities of BRAIN … kind of in addition to their “day jobs.” I think as enterprises emerge from their startup phase, which is typically the first 5 years, the question is how do you translate this into a sustainable enterprise, and yet maintain this cutting-edge innovation? … How do we leverage all the accomplishments that have been made, not just within BRAIN, but in molecular biology, in engineering, in chemistry and computer science, in data science. The initiative really will benefit from somebody thinking about this 24/7. © 2019 American Association for the Advancement of Science.

Keyword: Brain imaging; Chemical Senses (Smell & Taste)
Link ID: 27020 - Posted: 02.05.2020

Jon Hamilton Scientists have found a clue to how autism spectrum disorder disrupts the brain's information highways. The problem involves cells that help keep the traffic of signals moving smoothly through brain circuits, a team reported Monday in the journal Nature Neuroscience. The team found that in both mouse and human brains affected by autism, there's an abnormality in cells that produce a substance called myelin. That's a problem because myelin provides the "insulation" for brain circuits, allowing them to quickly and reliably carry electrical signals from one area to another. And having either too little or too much of this myelin coating can result in a wide range of neurological problems. For example, multiple sclerosis occurs when the myelin around nerve fibers is damaged. The results, which vary from person to person, can affect not only the signals that control muscles, but also the ones involved in learning and thinking. The finding could help explain why autism spectrum disorders include such a wide range of social and behavioral features, says Brady Maher, a lead investigator at the Lieber Institute for Brain Development and an associate professor in the psychiatry department at Johns Hopkins School of Medicine. "Myelination could be a problem that ties all of these autism spectrum disorders together," Maher says. And if that's true, he says, it might be possible to prevent or even reverse the symptoms using drugs that affect myelination. © 2020 npr

Keyword: Autism; Glia
Link ID: 27019 - Posted: 02.04.2020

By Shola Lawal These are tough times for fireflies. Like a lot of other insects, they face increasing threats from habitat loss, pesticides and pollution. But they also have a problem that’s unique to luminous bugs: It’s getting harder for them to reproduce because light pollution is outshining their mating signals. Fireflies, it turns out, use their special glowing powers in courtship: Males light up to signal availability and females respond with patterned flashes to show that they’re in the mood. But bright light from billboards, streetlights and houses is interfering and blocking potential firefly couples from pairing up. The problem can reach far from big cities: Bright light gets diffused in the atmosphere and can be reflected into the wilderness. In addition to messing with mating signals, it also disrupts the feeding patterns of the females of some species that glow to attract and eat males. The finding was part of a study published Monday in the journal BioScience. The study, by researchers at Tufts University and the International Union for Conservation of Nature, warned that fireflies could eventually face extinction globally because of multiple threats, including light pollution and habitat loss and habitat degradation from insecticides and chemical pollution. Many insects are affected by habitat loss, but fireflies have it particularly bad, said Sara M. Lewis, a biology professor at Tufts and the lead researcher on the study. “Some fireflies get hit especially hard when their habitat disappears because they need special conditions to complete their life cycle,” she said. Fireflies are a type of beetle. There are more than 2,000 species of them, found mainly in wetlands. But mangrove forests and marshes around the world are increasingly vanishing to make way for cash crops like palm oil, according to the new study. © 2020 The New York Times Company

Keyword: Sexual Behavior; Biological Rhythms
Link ID: 27018 - Posted: 02.04.2020

By Sue Halpern During the 2016 Presidential primary, SPARK Neuro, a company that uses brain waves and other physiological signals to delve into the subliminal mind, decided to assess people’s reactions to the Democratic candidates. The company had not yet launched, but its C.E.O., Spencer Gerrol, was eager to refine its technology. In a test designed to uncover how people are actually feeling, as opposed to how they say they are feeling, SPARK Neuro observed, among other things, that the cadence of Bernie Sanders’s voice grabbed people’s attention, while Hillary Clinton’s measured tones were a bore. A few months later, Katz Media Group, a radio-and-television-ad representative firm, hired Gerrol’s group to study a cohort of undecided voters in Florida and Pennsylvania. The company’s chief marketing officer, Stacey Schulman, picked SPARK Neuro because its algorithm took into account an array of neurological and physiological signals. “Subconscious emotion underlies conscious decision-making, which is interesting for the marketing world but critically important in the political realm,” Schulman told me. “This measures how the body is responding, and it happens before you articulate it.” Neuromarketing—gauging consumers’ feelings and beliefs by observing and measuring spontaneous, unmediated physiological responses to an ad or a sales pitch—is not new. “For a while, using neuroscience to do marketing was something of a fad, but it has been applied to commerce for a good ten years now,” Schulman said. Nielsen, the storied media-insight company, has a neuromarketing division. Google has been promoting what it calls “emotion analytics” to advertisers. A company called Realeyes claims to have trained artificial intelligence to “read emotions” through Webcams; another called Affectiva says that it “provides deep insight into unfiltered and unbiased consumer emotional response to brand content” through what it calls “facial coding.” Similarly, ZimGo Polling, a South Korean company that operates in the United States, has paired facial-recognition technology with “automated emotion understanding” and natural language processing to give “insights into how people feel about real-time issues,” and “thereby enables a virtual 24/7 town hall meeting with citizens.” This is crucial, according to the C.E.O. of ZimGo’s parent company, because “people vote on emotion.” © 2020 Condé Nast

Keyword: Attention; Emotions
Link ID: 27017 - Posted: 02.04.2020

Alison Abbott Researchers studying the biological basis of mental illness have conducted the first genomic analysis of schizophrenia in an African population, and have identified multiple rare mutations that occur more frequently in people with the condition. The mutations are mainly in genes that are important for brain development and the brain’s synapses, tiny structures that coordinate communication between neurons. The genes match those identified in other similar studies of schizophrenia — but nearly all previous research has been conducted in European or Asian populations. The latest work was published1 in Science on 31 January. This research is particularly important because Africa has represented a big gap in the populations that geneticists have studied, says psychiatric geneticist Andreas Meyer-Lindenberg, director of the Central Institute of Mental Health in Mannheim, Germany. He says that the work lends support to current hypotheses about the biological origins of schizophrenia, which can cause a range of symptoms including hallucinations, delusions and disordered thinking. Researchers think that each mutation might contribute a small amount to the overall risk of developing the condition, and that disruption to synapses could be crucial to the disease’s development. Over the past decade, as studies that use genome sequencing to identify the genetic basis of diseases have flourished, geneticists have come under increasing fire for failing to sample diverse populations, largely neglecting African people. Around 80% of participants in genetic studies are of European descent, and less than 3% are of African descent. © 2020 Springer Nature Limited

Keyword: Schizophrenia; Genes & Behavior
Link ID: 27016 - Posted: 02.04.2020

By Nicholas Bakalar Flavonols, a large class of compounds found in most fruits and vegetables, may be associated with a reduced risk for Alzheimer’s disease. Flavonols are known to have antioxidant and anti-inflammatory effects, and animal studies have suggested they may improve memory and learning. A study in Neurology involved 921 men and women, average age 81 and free of dementia, who reported their diet using well-validated food questionnaires. During an average follow-up of six years, 220 developed Alzheimer’s disease. People with the highest levels of flavonol intake tended to have higher levels of education and were more physically active. But after controlling for these factors plus age, sex, the Apo E4 gene (which increases the risk for dementia) and late-life cognitive activity, the scientists found that compared with those in the lowest one-fifth for flavonol intake, those in the highest one-fifth had a 48 percent reduced risk for Alzheimer’s disease. The study covered four types of flavonols: kaempferol, quercetin, isorhamnetin and myricetin. All except quercetin showed a strong association with Alzheimer’s risk reduction. These flavonols are available as supplements, but the lead author, Dr. Thomas M. Holland, a professor of medicine at Rush Medical College in Chicago, said that foods are a better source. “You get a broader intake of vitamins, minerals and bioactives in food than in the supplements,” he said. © 2020 The New York Times Company

Keyword: Alzheimers
Link ID: 27015 - Posted: 02.04.2020

Joanna McKittrick, Jae-Young Jung Slamming a beak against the trunk of a tree would seem like an activity that would cause headaches, jaw aches and serious neck and brain injuries. Yet woodpeckers can do this 20 times per second and suffer no ill effects. Woodpeckers are found in forested areas worldwide, except in Australia. These birds have the unusual ability to use their beaks to hammer into the trunks of trees to make holes to extract insects and sap. Even more impressive they do this without hurting themselves. We are materials scientists who study biological substances like bones, skins, feathers and shells found in nature. We are interested in the skull and tongue bone structure of woodpeckers, because we think their unusual anatomy could yield insights that could help researchers develop better protective head gear for humans. Concussions in people Woodpeckers endure many high impact shocks to their heads as they peck. They have strong tail feathers and claws that help them keep their balance as their head moves toward the tree trunk at 7 meters – 23 feet – per second. Then, when their beak strikes, their heads slow down at about 1,200 times the force of gravity (g). All of this occurs without the woodpecker sustaining concussions or brain damage. A concussion is a form of traumatic brain injury caused by repeated blows to the head. It is a common occurrence and happens frequently during contact sports like football or hockey. Repeated traumatic brain injury eventually causes a progressive brain disorder, chronic traumatic encephalopathy (CTE), which is irreversible and results in symptoms such as memory loss, depression, impulsivity, aggressiveness and suicidal behavior. The National Football League says concussions in football players occur at 80 g. So how do woodpeckers survive repeated 1,200 g impacts without harming their brain? © 2010–2020, The Conversation US, Inc.

Keyword: Brain Injury/Concussion; Evolution
Link ID: 27014 - Posted: 02.01.2020

Timothy Bella The headaches had become so splitting for Gerardo Moctezuma that the pain caused him to vomit violently. The drowsiness that came with it had intensified for months. But it wasn’t until Moctezuma, 40, fainted without explanation at a soccer match in Central Texas last year that he decided to figure out what was going on. When Jordan Amadio looked down at his MRI results, the neurosurgeon recognized — but almost couldn’t believe — what looked to be lodged in Moctezuma’s brain. As he opened up Moctezuma’s skull during an emergency surgery in May 2019, he was able to confirm what it was that had uncomfortably set up shop next to the man’s brain stem: a tapeworm measuring about an inch-and-a-half. “It’s very intense, very strong, because it made me sweat too, sweat from the pain,” Moctezuma said to KXAN. The clear and white parasite came from tapeworm larva that Amadio believes Moctezuma, who moved from Mexico to the U.S. 14 years before his diagnosis, might have had in his brain for more than a decade undetected. His neurological symptoms had intensified due to his neurocysticercosis, which was the direct result of the tapeworm living in his brain. The cyst would trigger hydrocephalus, an accumulation of cerebrospinal fluid that increased pressure to the skull to the point that the blockage and pain had become life-threatening. “It’s a remarkable case where a patient came in and, if he had not been treated urgently, he would have died from tremendous pressure in the brain,” Amadio, attending neurosurgeon at the Ascension Seton Brain and Spine Institute in Austin, told The Washington Post on Thursday night.

Keyword: Development of the Brain
Link ID: 27013 - Posted: 02.01.2020

By Elizabeth Pennisi It’s been a bad couple of weeks for behavioral ecologist Jonathan Pruitt—the holder of one of the prestigious Canada 150 Research Chairs—and it may get a lot worse. What began with questions about data in one of Pruitt’s papers has flared into a social media–fueled scandal in the small field of animal personality research, with dozens of papers on spiders and other invertebrates being scrutinized by scores of students, postdocs, and other co-authors for problematic data. Already, two papers co-authored by Pruitt, now at McMaster University, have been retracted for data anomalies; Biology Letters is expected to expunge a third within days. And the more Pruitt’s co-authors look, the more potential data problems they find. All papers using data collected or curated by Pruitt, a highly productive researcher who specialized in social spiders, are coming under scrutiny and those in his field predict there will be many retractions. The furor has even earned a Twitter hashtag—#PruittData. Yet even one of the researchers who initially probed Pruitt’s data cautions that what has happened remains unclear. “There is no hard evidence that [Pruitt’s] data are fabricated,” says behavioral ecologists Niels Dingemanse of Ludwig Maximilian University of Munich (LMU). © 2019 American Association for the Advancement of Science.

Keyword: Emotions; Evolution
Link ID: 27012 - Posted: 02.01.2020

Madeline Andrews, Aparna Bhaduri, Arnold Kriegstein What was going on with our brain organoids? As neuroscientists, we use these three-dimensional clusters of cells grown in petri dishes to learn more about how the human brain works. Researchers culture various kinds of organoids from stem cells – cells that have the potential to become one of many different cell types found throughout the body. We use chemical signals to direct stem cells to produce brain-like cells that together resemble certain structural aspects of a real brain. While they are not “brains in a dish” – organoids cannot function or think independently – the idea is that organoid models let scientists see developmental processes that may yield insights into how the human brain works. If researchers better understand normal development, we may be able to understand when and how things go wrong in diseases. When we recently compared our lab’s organoid cells to normal brain cells, we were surprised to find that they didn’t look as similar as we’d expected. Our brain organoids, each the size of a few millimeters, were stressed out. Our investigation into why has important implications for this popular new method since many labs are using it to study brain function and neurological disease. Without accurate models of the brain, scientists will not be able to work toward disease treatments. Our lab is particularly interested in the human cerebral cortex – the brain’s bumpy exterior – because it is so different in human beings than it is in any other species. The human cortex is proportionally bigger than in our closest living relatives, the great apes, containing more and different types of cells. It’s the source of many unique human abilities, including our cognitive capacity. © 2010–2020, The Conversation US, Inc.

Keyword: Development of the Brain
Link ID: 27011 - Posted: 01.31.2020

By Leah Shaffer Football’s concussion crisis has been part of the NFL for almost two decades. But the pros aren’t the only ones reevaluating their relationship with the game. Now, studies are finding that parents of younger children are increasingly concerned about the long-term impacts of playing football. A national survey from 2015 found that 25 percent of parents do not let their kids play contact sports due to fear of concussions, while an Aspen Institute report recently found that participation in tackle football declined by 12 percent among children ages 6 to 12 between 2016 and 2017. The research into the risks of youth football is still coming into shape, and there’s disagreement about just how universal and severe the risks are. Some researchers think football is dangerous for everybody; others are finding evidence that some kids might be more predisposed to health consequences than others. In the last two years, some researchers have shown that head hits in youth sports increase the risk of developing chronic traumatic encephalopathy, or CTE, an untreatable degenerative brain disease with symptoms ranging from memory loss to progressive dementia. Other studies have shown that the longer a person plays football, the higher the risk they have for developing symptoms associated with CTE. So, case closed, right? No — football is not the only risk factor in developing symptoms of CTE. The same study that found an association between repetitive head impact and dementia in CTE also found that cardiovascular disease and dementia in CTE were correlated. And a separate study of some 10,000 people found no association between participation in contact sports and later cognitive decline or increase in symptoms of depression. © 2020 ABC News Internet Ventures

Keyword: Brain Injury/Concussion; Development of the Brain
Link ID: 27010 - Posted: 01.31.2020

By Neuroskeptic A new neuroscience paper bears the remarkable title of Life without a brain. Although the title is somewhat misleading, this is still a rather interesting report about a unique rat who functioned extremely well despite having a highly abnormal brain. This case sheds new light on a number of famous examples of humans born with similar abnormalities. According to the authors of the new paper, Ferris et al., the rat in question was called R222 and it was discovered unexpectedly during testing as part of a batch of rats taking part in an experiment. R222 didn't actually have no brain, but it had a highly abnormal brain anatomy. Its brain was actually twice the size of a normal rat's, but much of it consisted of empty, fluid-filled space. The cerebral cortex was limited to a thin sheet surrounding the fluid spaces, although the total cortical volume was - surprisingly given the images shown above - only slightly less than normal - 575 μL vs. the normal ~615 μL. Despite the grossly abnormal appearance of R222's brain, the rat seemed to suffer no major impairments. Ferris et al. say that "R222’s general health, appearance and body weight were no different from the other rats in the cohort." The rodent's motor skills and memory function were within the normal range, although it did seem to be highly anxious. © 2020 Kalmbach Media Co.

Keyword: Development of the Brain
Link ID: 27009 - Posted: 01.31.2020

By Veronique Greenwood You might mistake jewel wings for their colorful cousins, dragonflies. New research shows that these two predators share something more profound than their appearance, however. In a paper published this month in Current Biology, Dr. Gonzalez-Bellido and colleagues reveal that the neural systems behind jewel wings’ vision are shared with dragonflies, with whom they have a common ancestor that lived before the dinosaurs. But over the eons, this brain wiring has adapted itself in different ways in each creature, enabling radically different hunting strategies. For flying creatures, instantaneous, highly accurate vision is crucial to survival. Recent research showed that birds of prey that fly faster also see changes in their field of vision more quickly, demonstrating the link between speed on the wing and speed in the brain. But the group of insects that includes jewel wings and dragonflies took to the air long before birds were even on the evolutionary horizon, and their vision is swifter than any vertebrate’s studied thus far, said Dr. Gonzalez-Bellido. Researchers looking to understand how their vision, flight and hunting abilities are connected are thus particularly interested in the neurons that send visual information to the wings. But recordings made in the lab by Dr. Gonzalez-Bellido and her colleagues confirmed that dragonflies rise up in a straight line to seize unsuspecting insects from below, almost like their prey had stepped on a land mine. This eerie climb may contribute to their startling success rate: Dragonflies snag their prey 97 percent of the time. The difference in hunting behavior may be linked to the placement of the insects’ eyes. Jewel wings’ eyes are on either side of the head, facing forward. The eyes of these dragonflies — the species Sympetrum vulgatum, also known as the vagrant darter — encase the top of the insect’s head in an iridescent dome, with a thin line running down the middle the only visible reminder that they may have once been separate. © 2020 The New York Times Company

Keyword: Vision; Evolution
Link ID: 27008 - Posted: 01.29.2020

Jordana Cepelewicz Part of the brain’s allure for scientists is that it is so deeply personal — arguably the core of who we are and what makes us human. But that fact also renders a large share of imaginable experiments on it monstrous, no matter how well intended. Neuroscientists have often had to swallow their frustration and settle for studying the brains of experimental animals or isolated human neurons kept alive in flat dishes — substitutes that come with their own ethical, practical and conceptual limitations. A new world of possibilities opened in 2008, however, when researchers learned how to create cerebral organoids — tiny blobs grown from human stem cells that self-organize into brainlike structures with electrically active neurons. Though no bigger than a pea, organoids hold enormous promise for improving our understanding of the brain: They can replicate aspects of human development and disease once thought impossible to observe in the laboratory. Scientists have already used organoids to make discoveries about schizophrenia, autism spectrum disorders and the microcephaly caused by the Zika virus. Yet the study of brain organoids can also be fraught with ethical dilemmas. “In order for it to be a good model, you want it to be as human as possible,” said Hank Greely, a law professor at Stanford University who specializes in ethical and legal issues in the biosciences. “But the more human it gets, the more you’re backing into the same sorts of ethics questions that are the reasons why you can’t just use living humans.” In the popular imagination, fueled by over-the-top descriptions of organoids as “mini-brains,” these questions often center on whether the tissue might become conscious and experience its unnatural existence as torture. The more immediate, realistic concerns that trouble experts are less sensational but still significant. It also doesn’t help that the study of organoids falls into an odd gap between other areas of research, complicating formal ethical oversight. Still, no one wants to see brain organoids’ potential discarded lightly. All Rights Reserved © 2020

Keyword: Development of the Brain
Link ID: 27007 - Posted: 01.29.2020

By Theodor Schaarschmidt A 51-year-old man I will call “Mr. Pinocchio” had a strange problem. When he tried to tell a lie, he often passed out and had convulsions. In essence, he became a kind of Pinocchio, the fictional puppet whose nose grew with every fib. For the patient, the consequences were all too real: he was a high-ranking official in the European Economic Community (since replaced by the European Union), and his negotiating partners could tell immediately when he was bending the truth. His condition, a symptom of a rare form of epilepsy, was not only dangerous, it was bad for his career. Doctors at the University Hospitals of Strasbourg in France discovered that the root of the problem was a tumor about the size of a walnut. The tumor was probably increasing the excitability of a brain region involved in emotions; when Mr. Pinocchio lied, this excitability caused a structure called the amygdala to trigger seizures. Once the tumor was removed, the fits stopped, and he was able to resume his duties. The doctors, who described the case in 1993, dubbed the condition the “Pinocchio syndrome.” Mr. Pinocchio’s plight demonstrates the far-reaching consequences of even minor changes in the structure of the brain. But perhaps just as important, it shows that lying is a major component of the human behavioral repertoire; without it, we would have a hard time coping. When people speak unvarnished truth all the time—as can happen when Parkinson’s disease or certain injuries to the brain’s frontal lobe disrupt people’s ability to lie—they tend to be judged tactless and hurtful. In everyday life, we tell little white lies all the time, if only out of politeness: Your homemade pie is awesome (it’s awful). No, Grandma, you’re not interrupting anything (she is). A little bit of pretense seems to smooth out human relationships without doing lasting harm. © 2020 Scientific American

Keyword: Emotions
Link ID: 27006 - Posted: 01.29.2020