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By Yasemin Saplakoglu On warm summer nights, green lacewings flutter around bright lanterns in backyards and at campsites. The insects, with their veil-like wings, are easily distracted from their natural preoccupation with sipping on flower nectar, avoiding predatory bats and reproducing. Small clutches of the eggs they lay hang from long stalks on the underside of leaves and sway like fairy lights in the wind. The dangling ensembles of eggs are beautiful but also practical: They keep the hatching larvae from immediately eating their unhatched siblings. With sickle-like jaws that pierce their prey and suck them dry, lacewing larvae are “vicious,” said James Truman, a professor emeritus of development, cell and molecular biology at the University of Washington. “It’s like ‘Beauty and the Beast’ in one animal.” This Jekyll-and-Hyde dichotomy is made possible by metamorphosis, the phenomenon best known for transforming caterpillars into butterflies. In its most extreme version, complete metamorphosis, the juvenile and adult forms look and act like totally different species. Metamorphosis is not an exception in the animal kingdom; it’s almost a rule. More than 80% of the known animal species today, mainly insects, amphibians and marine invertebrates, undergo some form of metamorphosis or have complex, multistage life cycles. The process of metamorphosis presents many mysteries, but some of the most deeply puzzling ones center on the nervous system. At the center of this phenomenon is the brain, which must code for not one but multiple different identities. After all, the life of a flying, mate-seeking insect is very different from the life of a hungry caterpillar. For the past half-century, researchers have probed the question of how a network of neurons that encodes one identity — that of a hungry caterpillar or a murderous lacewing larva — shifts to encode an adult identity that encompasses a completely different set of behaviors and needs. Truman and his team have now learned how much metamorphosis reshuffles parts of the brain. In a recent study published in the journal eLife, they traced dozens of neurons in the brains of fruit flies going through metamorphosis. They found that, unlike the tormented protagonist of Franz Kafka’s short story “The Metamorphosis,” who awakes one day as a monstrous insect, adult insects likely can’t remember much of their larval life. Although many of the larval neurons in the study endured, the part of the insect brain that Truman’s group examined was dramatically rewired. That overhaul of neural connections mirrored a similarly dramatic shift in the behavior of the insects as they changed from crawling, hungry larvae to flying, mate-seeking adults. All Rights Reserved © 2023

Keyword: Learning & Memory
Link ID: 28860 - Posted: 07.27.2023

Liam Drew Scientific advances are rapidly making science-fiction concepts such as mind-reading a reality — and raising thorny questions for ethicists, who are considering how to regulate brain-reading techniques to protect human rights such as privacy. On 13 July, neuroscientists, ethicists and government ministers discussed the topic at a Paris meeting organized by UNESCO, the United Nations scientific and cultural agency. Delegates plotted the next steps in governing such ‘neurotechnologies’ — techniques and devices that directly interact with the brain to monitor or change its activity. The technologies often use electrical or imaging techniques, and run the gamut from medically approved devices, such as brain implants for treating Parkinson’s disease, to commercial products such as wearables used in virtual reality (VR) to gather brain data or to allow users to control software. How to regulate neurotechnology “is not a technological discussion — it’s a societal one, it’s a legal one”, Gabriela Ramos, UNESCO’s assistant director-general for social and human sciences, told the meeting. Advances in neurotechnology include a neuroimaging technique that can decode the contents of people’s thoughts, and implanted brain–computer interfaces (BCIs) that can convert people’s thoughts of handwriting into text1. The field is growing fast — UNESCO’s latest report on neurotechnology, released at the meeting, showed that, worldwide, the number of neurotechnology-related patents filed annually doubled between 2015 and 2020. Investment rose 22-fold between 2010 and 2020, the report says, and neurotechnology is now a US$33-billion industry. One area in need of regulation is the potential for neurotechnologies to be used for profiling individuals and the Orwellian idea of manipulating people’s thoughts and behaviour. Mass-market brain-monitoring devices would be a powerful addition to a digital world in which corporate and political actors already use personal data for political or commercial gain, says Nita Farahany, an ethicist at Duke University in Durham, North Carolina, who attended the meeting. © 2023 Springer Nature Limited

Keyword: Brain imaging
Link ID: 28859 - Posted: 07.27.2023

By Tanvi Dutta Gupta The Arctic Ocean is a noisy place. Creatures of the deep have learned to live with the cacophony of creaking ice sheets and breaking icebergs, but humanmade sources of noise from ships and oil and gas infrastructure are altering that natural submarine soundscape. Now, a research team has found that even subtle underwater noise pollution can cause narwhals to make shallower dives and cut their hunts short. The research, published today in Science Advances, uncovers “some really great information on a species we know very little about,” says Ari Friedlaender, an ocean ecologist at the University of California, Santa Cruz, not involved in the study. Knowing how the whales react to these noises could help conservationists “act proactively” to protect the animals in their Arctic home where warming waters already threaten their lifestyles. Narwhals—with their long, unicornlike horns extending from their faces—live in one of the most extreme environments in the world, explains Outi Tervo, an ecologist at the Greenland Institute of Natural Resources and the study’s first author. Each narwhal returns in summer to the same small fjord where it was born in order to feed on fish, squid, and shrimp. As humans increasingly encroach on Arctic waters, though, scientists, conservationists, and Inuit communities have worried about how development and ship traffic will affect the whales. Many of Greenland’s Inuit communities rely on the narwhals as a culturally important food source. When Greenland’s government started to auction new permits for offshore oil exploration in 2011, Tervo and colleagues decided to examine whether the noise pollution associated with such development affected narwhals. For instance, boats exploring the sea floor tow instruments called airguns, which blast air a few meters below the vessels to sonically suss out the presence of cavities that may contain oil and gas. Those pulses can be the “loudest sound put in the ocean by humans,” says study co-author Susanna Blackwell, a biologist with Greeneridge Sciences.

Keyword: Animal Communication; Hearing
Link ID: 28858 - Posted: 07.27.2023

by Giorgia Guglielmi Mice with a mutation that boosts the activity of the autism-linked protein UBE3A show an array of behaviors reminiscent of the condition, a new study finds. The behaviors differ depending on whether the animals inherit the mutation from their mother or their father, the work also reveals. The results add to mounting evidence that hyperactive UBE3A leads to autism. Duplications of the chromosomal region that includes UBE3A have been associated with autism, whereas deletions and mutations that destroy the gene’s function are known to cause Angelman syndrome, which is characterized by developmental delay, seizures, lack of speech, a cheerful demeanor and, often, autism. “UBE3A is on a lot of clinicians’ radar because it is well known to be causative for Angelman syndrome when mutated or deleted,” says lead investigator Mark Zylka, professor of cell biology and physiology at the University of North Carolina at Chapel Hill. “What our study shows is that just because you have a mutation in UBE3A, it doesn’t mean that it’s going to be Angelman syndrome.” In the cell, UBE3A is involved in the degradation of proteins, and “gain-of-function” mutations — which send the UBE3A protein into overdrive — result in enhanced degradation of its targets, including UBE3A itself. Studying the effects of these mutations could provide insight into how they affect brain development and suggest targets for therapies, says study investigator Jason Yi, assistant professor of neuroscience at Washington University in St. Louis, Missouri. Gain-of-function mutations in UBE3A can disrupt early brain development and may contribute to neurodevelopmental conditions that are distinct from Angelman syndrome, Yi and Zylka have shown in previous studies. One of the mutations they analyzed had been found in an autistic child, so the team used CRISPR to create mice with this mutation. © 2023 Simons Foundation

Keyword: Autism
Link ID: 28857 - Posted: 07.27.2023

Lilly Tozer A study that followed thousands of people over 25 years has identified proteins linked to the development of dementia if their levels are unbalanced during middle age. The findings, published in Science Translational Medicine on 19 July1, could contribute to the development of new diagnostic tests, or even treatments, for dementia-causing diseases. Most of the proteins have functions unrelated to the brain. “We’re seeing so much involvement of the peripheral biology decades before the typical onset of dementia,” says study author Keenan Walker, a neuroscientist at the US National Institute on Aging in Bethesda, Maryland. Equipped with blood samples from more than 10,000 participants, Walker and his colleagues questioned whether they could find predictors of dementia years before its onset by looking at a person’s proteome — the collection of all the proteins expressed throughout the body. They searched for any signs of dysregulation — when proteins are at levels much higher or lower than normal. The samples were collected as part of an ongoing study that began in 1987. Participants returned for examination six times over three decades, and during this time, around 1 in 5 of them developed dementia. The researchers found 32 proteins that, if dysregulated in people aged 45 to 60, were strongly associated with an elevated chance of developing dementia in later life. It is unclear how exactly these proteins might be involved in the disease, but the link is “highly unlikely to be due to just chance alone”, says Walker © 2023 Springer Nature Limited

Keyword: Alzheimers
Link ID: 28856 - Posted: 07.22.2023

By Robert Kolker Barb was the youngest in her large Irish Catholic family — a surprise baby, the ninth child, born 10 years after the eighth. Living in the suburbs of Pittsburgh, her family followed the football schedule: high school games on Friday night, college games on Saturday, the Steelers on Sunday. Dad was an engineer, mom was a homemaker and Barb was the family mascot, blond and adorable, watching her brothers and sisters finish school and go on to their careers. Barb was the only child left at home in the 1980s to witness the seams of her parents’ marriage come apart. Her father all but left, and her mother turned inward, sitting quietly in front of the television, always smoking, often with a cocktail. Something had overtaken her, though it wasn’t clear what. Barb observed it all with a measure of detachment; her parents had been older than most, and her sisters and brothers supplied more than enough parental energy to make up the difference. And so in 1990, when Barb was 14 and her mother learned she had breast cancer and died within months at the age of 62, Barb was shattered and bewildered but also protected. Her siblings had already stepped in, three of them living back home. Together they arrived at a shared understanding of the tragedy. Their mother could have lived longer if she had cut back on her drinking sooner or gone to see a doctor or hadn’t smoked. Six years later, Barb was 20 and in college when someone else in the family needed help. Her sister Christy was the second-born, 24 years older than Barb and the star of the family in many ways. She had traveled extensively as a pharmaceutical-company executive while raising two children with her husband in a nice house in a New Jersey suburb. But where once Christy was capable and professionally ambitious and socially conscious, now, at 44, she was alone, her clothes unkempt and ripped, her hair unwashed, her marriage over. Again, the family came together: Susan, the third-born, volunteered to take care of Christy full time, and Jenny, the eighth, searched for a specialist (the family members asked to be identified by their first names to protect their privacy). Depression was the first suspected diagnosis, then schizophrenia, though neither seemed quite right. Christy wasn’t sad or delusional; she wasn’t even upset. It was more as if she were reverting to a childlike state, losing her knack for self-regulation. Her personality was diluting — on its way out, with seemingly nothing to replace it. © 2023 The New York Times Company

Keyword: Alzheimers; Genes & Behavior
Link ID: 28855 - Posted: 07.22.2023

Geneva Abdul The so-called “brain fog” symptom associated with long Covid is comparable to ageing 10 years, researchers have suggested. In a study by King’s College London, researchers investigated the impact of Covid-19 on memory and found cognitive impairment highest in individuals who had tested positive and had more than three months of symptoms. The study, published on Friday in a clinical journal published by The Lancet, also found the symptoms in affected individuals stretched to almost two years since initial infection. “The fact remains that two years on from their first infection, some people don’t feel fully recovered and their lives continue to be impacted by the long-term effects of the coronavirus,” said Claire Steves, a professor of ageing and health at King’s College. “We need more work to understand why this is the case and what can be done to help.” An estimated two million people living in the UK were experiencing self-reported long Covid – symptoms continuing for more than four weeks since infection – as of January 2023, according to the 2023 government census. Commonly reported symptoms included fatigue, difficulty concentrating, shortness of breath and muscle aches. The study included more than 5,100 participants from the Covid Symptom Study Biobank, recruited through a smartphone app. Through 12 cognitive tests measuring speed and accuracy, researchers examined working memory, attention, reasoning and motor controls between two periods of 2021 and 2022. © 2023 Guardian News & Media Limited or

Keyword: Learning & Memory; Attention
Link ID: 28854 - Posted: 07.22.2023

Max Kozlov Dead in California but alive in New Jersey: that was the status of 13-year-old Jahi McMath after physicians in Oakland, California, declared her brain dead in 2013, after complications from a tonsillectomy. Unhappy with the care that their daughter received and unwilling to remove life support, McMath’s family moved with her to New Jersey, where the law allowed them to lodge a religious objection to the declaration of brain death and keep McMath connected to life-support systems for another four and a half years. Prompted by such legal discrepancies and a growing number of lawsuits around the United States, a group of neurologists, physicians, lawyers and bioethicists is attempting to harmonize state laws surrounding the determination of death. They say that imprecise language in existing laws — as well as research done since the laws were passed — threatens to undermine public confidence in how death is defined worldwide. “It doesn’t really make a lot of sense,” says Ariane Lewis, a neurocritical care clinician at NYU Langone Health in New York City. “Death is something that should be a set, finite thing. It shouldn’t be something that’s left up to interpretation.” Since 2021, a committee in the Uniform Law Commission (ULC), a non-profit organization in Chicago, Illinois, that drafts model legislation for states to adopt, has been revising its recommendation for the legal determination of death. The drafting committee hopes to clarify the definition of brain death, determine whether consent is required to test for it, specify how to handle family objections and provide guidance on how to incorporate future changes to medical standards. The broader membership of the ULC will offer feedback on the first draft of the revised law at a meeting on 26 July. After members vote on it, the text could be ready for state legislatures to consider by the middle of next year. But as the ULC revision process has progressed, clinicians who were once eager to address these issues have become increasingly worried. © 2023 Springer Nature Limited

Keyword: Consciousness
Link ID: 28853 - Posted: 07.22.2023

By Pam Belluck Treating Alzheimer’s patients as early as possible — when symptoms and brain pathology are mildest — provides a better chance of slowing cognitive decline, a large study of an experimental Alzheimer’s drug presented Monday suggests. The study of 1,736 patients reported that the drug, donanemab, made by Eli Lilly, can modestly slow the progression of memory and thinking problems in early stages of Alzheimer’s, and that the slowing was greatest for early-stage patients when they had less of a protein that creates tangles in the brain. For people at that earlier stage, donanemab appeared to slow decline in memory and thinking by about four and a half to seven and a half months over an 18-month period compared with those taking a placebo, according to the study, published in the journal JAMA. Among people with less of the protein, called tau, slowing was most pronounced in those younger than 75 and those who did not yet have Alzheimer’s but had a pre-Alzheimer’s condition called mild cognitive impairment, according to data presented Monday at the Alzheimer’s Association International Conference in Amsterdam. “The earlier you can get in there, the more you can impact it before they’ve already declined and they’re on this fast slope,” Dr. Daniel Skovronsky, Eli Lilly’s chief medical and scientific officer, said in an interview. “No matter how you cut the data — earlier, younger, milder, less pathology — every time, it just looks like early diagnosis and early intervention are the key to managing this disease,” he added. The findings and the recent approval of another drug that modestly slows decline in the early stages of Alzheimer’s, Leqembi, signal a potentially promising turn in the long, rocky path toward finding effective medications for Alzheimer’s, a brutal disease that plagues more than six million Americans. Donanemab is currently being considered for approval by the Food and Drug Administration. © 2023 The New York Times Company

Keyword: Alzheimers
Link ID: 28852 - Posted: 07.19.2023

Nicola Davis Science correspondent Taking part in activities such as chess, writing a journal, or educational classes in older age may help to reduce the risk of dementia, a study has suggested. According to the World Health Organization, more than 55 million people have the disease worldwide, most of them older people. However experts have long emphasised that dementia is not an inevitable part of ageing, with being active, eating well and avoiding smoking among the lifestyle choices that can reduce risk. Now researchers have revealed fresh evidence that challenging the brain could also be beneficial. Writing in the journal Jama Network Open, researchers in the US and Australia report how they used data from the Australian Aspree Longitudinal Study of Older Persons covering the period from 1 March 2010 to 30 November 2020. Participants in the study were over the age of 70, did not have a major cognitive impairment or cardiovascular disease when recruited between 2010 and 2014, and were assessed for dementia through regular study visits. In the first year, participants were asked about their social networks. They were also questioned on whether they undertook certain leisure activities or trips out to venues such as galleries or restaurants, and how frequently: never, rarely, sometimes, often or always. The team analysed data from 10,318 participants, taking into account factors such as age, sex, smoking status, education, socioeconomic status, and whether participants had other diseases such as diabetes. The results reveal that for activities such as writing letters or journals, taking educational classes or using a computer, increasing the frequency of participation by one category, for example from “sometimes” to “often”, was associated with an 11% drop in the risk of developing dementia over a 10-year period. Similarly, increased frequency of activities such as card games, chess or puzzle-solving was associated with a 9% reduction in dementia risk. © 2023 Guardian News & Media Limited

Keyword: Alzheimers; Learning & Memory
Link ID: 28851 - Posted: 07.19.2023

by Holly Barker By bloating brain samples and imaging them with a powerful microscope, researchers can reconstruct neurons across the entire mouse brain, according to a new preprint. The technique could help scientists uncover the neural circuits responsible for complex behaviors, as well as the pathways that are altered in neurological conditions. Tracking axons can help scientists understand how individual neurons and brain areas communicate over long distances. But tracing their path through the brain is tricky, says study investigator Adam Glaser, senior scientist at the Allen Institute for Neural Dynamics in Seattle, Washington. Axons, which are capable of spanning the entire brain, can be less than a micrometer in diameter, so mapping their route requires detailed imaging, he says. One existing approach involves a microscope that slices off an ultra-thin section of the brain and then scans it, repeating the process about 20,000 times to capture the entire mouse brain. Scientists then blend the images together to form a 3D reconstruction of neuronal pathways. But the process takes several days and is therefore more prone to complications — bubbles forming on the lens, say — than faster techniques, Glaser says. And slicing can distort the edges of the image, making it “challenging or impossible” to stitch them back together, says Paul Tillberg, principal scientist at the Howard Hughes Medical Institute’s Janelia Research Campus in Ashburn, Virginia, who was not involved in the study. “This is particularly an issue when reconstructing brain-wide axonal projections, where a single point of confusion can misalign an entire axonal arbor to the wrong neuron,” he says. © 2023 Simons Foundation

Keyword: Brain imaging
Link ID: 28850 - Posted: 07.19.2023

By Alejandra Manjarrez Rafael Jiménez Medina learned how to hunt elusive Iberian moles in the fields of southern Spain in the 1980s, when he was a young PhD student in genetics at the University of Granada. A local hunter of the moles (Talpa occidentalis) taught him how to capture these solitary, aggressive and territorial animals. The moles dig subterranean galleries and labyrinths in the meadows of the Iberian Peninsula, especially those with soft soils rich in earthworms, their favorite food. Such activity can benefit the soil — by aerating or mixing it — but the moles’ presence and constant movement in cultivated land raise the ire of farmers, who pay hunters to get rid of them. Jiménez Medina had a different motivation for hunting these subterranean mammals. His doctoral project was to visualize and analyze their chromosomes, which meant collecting, preparing and examining samples from the testes of males. His lab analyses led to a curious finding: Some of the moles he had identified as males were in fact genetically females — that is, their sex chromosomes were XX (female) and not XY (male). The confusion, we now know, stems from the unusual composition of the reproductive organs of female moles. In contrast to most female mammals, which have only ovaries, female Iberian moles also have testicular tissue. This tissue anatomically resembles male testicles but differs in that it produces testosterone but no sperm. The female mole’s organs are composed of both an ovarian and a testicular portion and are known as ovotestes. In addition, female moles have a clitoris covered with a foreskin and with an elongated appearance that resembles a penis; they urinate through this structure. Another unique anatomical feature is that during these females’ juvenile stage, the vaginal orifice remains closed. © 2023 Annual Reviews

Keyword: Sexual Behavior; Evolution
Link ID: 28849 - Posted: 07.19.2023

By David Ovalle The evolving overdose crisis in the United States is making another lethal turn, federal disease trackers reported Wednesday: Increasingly, people dying from opioids are also using stimulants such as cocaine and methamphetamine. An analysis by the Centers for Disease Control and Prevention shows that between 2011 and 2021, the age-adjusted rate of overdose deaths involving opioids and cocaine nearly quintupled, far outpacing the rate of deaths involving only cocaine. In 2021 alone, nearly 80 percent of the 24,486 cocaine overdose deaths recorded in the United States also involved an opioid. Experts say it represents the latest wave of the nation’s drug epidemic. For many users injecting or smoking fentanyl for some time, “adding a stimulant makes the drug feel like it did in the beginning,” said Daniel Ciccarone, a professor of addiction medicine at the University of California at San Francisco who has been studying the simultaneous use of stimulants and opioids. The federal analysis adds clarity to the staggering number of drug poisonings, largely driven by fentanyl, which can be up to 50 times more powerful than heroin. The CDC estimates that in 2022, more than 110,000 people succumbed to overdoses, edging past the previous year but representing a plateau from earlier spikes. Preliminary CDC data also suggest a slight increase in deaths in 2022 involving opioids taken with cocaine and psychostimulants such as meth. “These aren’t mutually exclusive categories. Someone can die of more than one drug,” said CDC researcher Merianne Rose Spencer, who led the analysis. The international cocaine market has thrived despite shutdowns associated with the coronavirus pandemic, according to the U.N.’s Global Report on Cocaine 2023, with record production in Latin America, new trafficking hubs in Africa and increased seizures.

Keyword: Drug Abuse
Link ID: 28848 - Posted: 07.19.2023

Lilly Tozer Injecting ageing monkeys with a ‘longevity factor’ protein can improve their cognitive function, a study reveals. The findings, published on 3 July in Nature Aging1, could lead to new treatments for neurodegenerative diseases. It is the first time that restoring levels of klotho — a naturally occurring protein that declines in our bodies with age — has been shown to improve cognition in a primate. Previous research on mice had shown that injections of klotho can extend the animals’ lives and increases synaptic plasticity2 — the capacity to control communication between neurons, at junctions called synapses. “Given the close genetic and physiological parallels between primates and humans, this could suggest potential applications for treating human cognitive disorders,” says Marc Busche, a neurologist at the UK Dementia Research Institute group at University College London. The protein is named after the Greek goddess Clotho, one of the Fates, who spins the thread of life. The study involved testing the cognitive abilities of old rhesus macaques (Macaca mulatta), aged around 22 years on average, before and after a single injection of klotho. To do this, researchers used a behavioural experiment to test for spatial memory: the monkeys had to remember the location of an edible treat, placed in one of several wells by the investigator, after it was hidden from them. Study co-author Dena Dubal, a physician-researcher at the University of California, San Francisco, compares the test to recalling where you left your car in a car park, or remembering a sequence of numbers a couple of minutes after hearing it. Such tasks become harder with age. The monkeys performed significantly better in these tests after receiving klotho — before the injections they identified the correct wells around 45% of the time, compared with around 60% of the time after injection. The improvement was sustained for at least two weeks. Unlike in previous studies involving mice, relatively low doses of klotho were effective. This adds an element of complexity to the findings, which suggests a more nuanced mode of actions than was previously thought, Busche says. © 2023 Springer Nature Limited

Keyword: Learning & Memory; Development of the Brain
Link ID: 28847 - Posted: 07.06.2023

Jon Hamilton Dr. Josef Parvizi remembers meeting a man with epilepsy whose seizures were causing some very unusual symptoms. "He came to my clinic and said, 'My sense of self is changing,'" says Parvizi, a professor of neurology at Stanford University. The man told Parvizi that he felt "like an observer to conversations that are happening in my mind" and that "I just feel like I'm floating in space." Parvizi and a team of researchers would eventually trace the man's symptoms to a "sausage-looking piece of brain" called the anterior precuneus. This area, nestled between the brain's two hemispheres, appears critical to a person's sense of inhabiting their own body, or bodily self, the team recently reported in the journal Neuron. The finding could help researchers develop forms of anesthesia that use electrical stimulation instead of drugs. It could also help explain the antidepressant effects of mind-altering drugs like ketamine. It took Parvizi's team years of research to discover the importance of this obscure bit of brain tissue. In 2019, when the man first came to Stanford's Comprehensive Epilepsy Program, Parvizi thought his symptoms were caused by seizures in the posteromedial cortex, an area toward the back of the brain. This area includes a brain network involved in the narrative self, a sort of internal autobiography that helps us define who we are. Parvizi's team figured that the same network must be responsible for the bodily self too. "Everybody thought, 'Well, maybe all kinds of selves are being decoded by the same system,'" he says. © 2023 npr

Keyword: Attention; Consciousness
Link ID: 28846 - Posted: 07.06.2023

By Anil Seth In 1870, Alfred Russell Wallace wagered £500—a huge sum in those days—that he could prove the flat-Earther John Hampden wrong. Wallace duly did so, but the aggrieved Hampden never paid up. Since then, a lively history of scientific wagers has ensued—many of them instigated by Stephen Hawking. Just last month in New York, the most famous recent wager was settled: a 25-year-old bet over one of the last great mysteries in science and philosophy. The bettors were neuroscientist Christof Koch and philosopher David Chalmers, both known for their pioneering work on the nature of consciousness. Chalmers won. Koch paid up. Back in the late 1990s, consciousness science was full of renewed promise. Koch—a natural optimist—believed that 25 years was more than enough time for scientists to uncover the neural correlates of consciousness: those patterns of brain activity that underlie each and every one of our conscious experiences. Chalmers, a philosopher and therefore something of a pessimist by profession, demurred. In 1998, the pair staked a crate of fine wine on the outcome. The bet was finally called at the annual meeting of the Association for the Scientific Study of Consciousness in New York a couple of weeks ago. Koch graciously handed Chalmers a bottle of Madeira on the conference stage. While much more is known about consciousness today than in the ’90s, its true neural correlates—and indeed a consensus theory of consciousness—still elude us. What helped resolve the wager was the outcome, or rather the lack of a decisive outcome, of an “adversarial collaboration” organized by a consortium called COGITATE. Adversarial collaborations encourage researchers from different theoretical camps to jointly design experiments that can distinguish between their theories. In this case, the theories in question were integrated information theory (IIT), the brainchild of Giulio Tononi, and the neuronal global workspace theory (GWT), championed by Stanislas Dehaene. The two scientists made predictions, based on their respective theories, about what kinds of brain activity would be recorded in an experiment in which participants looked at a series of images—but neither predicted outcome fully played out. © 2023 NautilusNext Inc.,

Keyword: Consciousness
Link ID: 28845 - Posted: 07.06.2023

By Tammy Worth In two decades as a pediatrician, Jason Reynolds has had no success treating patients with opioid use disorder by sending them to rehab. But five years ago, when his Massachusetts practice, Wareham Pediatric Associates PC, became the first in the state to offer medication therapy to adolescent patients, he saw dramatic results. The first patient he treated with medication, a young man named Nate, had overdosed on opioids twice in the 24-hour period before seeing Reynolds. But that patient has had no opioid relapses since starting drug therapy. Reynolds’ success received a lot of media attention, and one interviewer, he recalls, asked Nate if any of his friends would also consider starting the treatment. Reynolds is among a small minority of pediatricians using medication to treat opioid use disorder in adolescents. Fewer than 2 percent of all physicians prescribing the medications are pediatricians, and many youth rehabilitation facilities don’t offer them at all. Medication for opioid use disorder (MOUD) uses buprenorphine or methadone to reduce cravings and withdrawal symptoms, or naltrexone to block the high that users would otherwise get if they decided to use opioids. Though MOUD is often used to treat adults, several barriers have prevented it from being adopted more widely for youth. Reynolds and a handful of other practitioners across the country are now working to provide education and training to other health care providers, hoping to increase use of this life-saving treatment. Opioid use among US youth is on the rise nationally, with diagnoses increasing from 0.26 per 100,000 person-years in 2001 to 1.51 in 2014. Overdose deaths have also spiked, more than doubling among youth ages 14 to 18, from 492 in 2019 to 1,146 in 2021. © 2023 Annual Reviews

Keyword: Drug Abuse; Development of the Brain
Link ID: 28844 - Posted: 07.06.2023

By Stephanie Pappas Have you felt butterflies in your stomach or hunger pangs? Those “gut feelings” happen thanks to the vagus nerve, which is a superhighway that connects the brain and the gut. In recent years the vagus nerve has become an intriguing target for researchers looking to cure disorders of both the brain and the body. Vagus nerve stimulation—usually achieved with an electrode implanted in the neck to deliver electrical pulses directly to the nerve—is an approved treatment for epilepsy and some forms of depression. Scientists are now studying vagus nerve stimulation (VNS) for disorders such as rheumatoid arthritis and the inflammatory bowel disease Crohn’s. What gives this nerve such widespread impact? The vagus nerve is the longest of the cranial nerves, which emerge directly from the brain rather than traveling through the spinal cord. It begins at an opening at the base of the skull and runs down the neck and into the abdomen, where it collects signals from the viscera and helps regulate the automatic processes of the body, from digestion to sleep to inflammation. About 80 percent of its signals are sensory ones that travel from the inner organs up to the brain, while the other 20 percent travel from the brain to the body and regulate things such as intestinal contractions and heart rate. The vagus nerve is the key player in the parasympathetic nervous system, which is the “rest and digest” system that calms the body during times of low stress. “If you are relaxed, if you are sleeping, if you are in a restorative phase, it’s the vagus nerve dominating,” says Gregor Hasler, a psychiatrist at the University of Fribourg in Switzerland, who has written about the gut-brain connection.

Keyword: Depression; Epilepsy
Link ID: 28843 - Posted: 07.06.2023

By Darren Incorvaia When Ambika Kamath was a graduate student in evolutionary biology at Harvard University, she knew one thing for sure: She wasn’t going to research anoles, the lizards that her adviser, Jonathan Losos, specialized in. “I started out as one of those rebellious renegades,” Kamath says, determined to pursue her own research subject. So she went to India for a couple of years to study the poorly understood fan-throated lizards. But when she tried to map out their territories, she found chaos. “All of the lizards were moving everywhere,” she says. Losos encouraged her to work with anoles after all, because it was well established that males hold individual territories that they protect from other males, and females only mate with the male whose territory they reside in. That would make it more straightforward for Kamath to study how anole territoriality differed across habitat types, like forests and parks. So Kamath went to Florida, where she identified individual anoles and tracked their movements day in, day out. Kamath studied the anoles “in a larger area, in a longer period of time than anyone else had ever done,” says Losos, who is now at Washington University in St. Louis. But instead of revealing territorial differences, this massive dataset showed that the anoles weren’t actually territorial in the first place. Kamath looked into the historical record to see where the idea of anole territoriality originated. It started with a 1933 paper that described frequent sexual behavior between male lizards in the lab. The authors had concluded that this lab behavior must be “prevented by something” in the wild, Kamath says, which they inferred was the males protecting territories. “The very first conclusion,” she says, “was based on a homophobic response to observing male-male copulation.” That shaky conclusion caught on, and later researchers assumed it to be true. Introducing a feminist perspective © Society for Science & the Public 2000–2023.

Keyword: Sexual Behavior; Attention
Link ID: 28842 - Posted: 07.06.2023

By Sujata Gupta Teenagers in the United States are in crisis. That news got hammered home earlier this year following the release of a nationally representative survey showing that over half of high school girls reported persistent feelings of “sadness or hopelessness” — common words used to screen for depression. Almost a third of teenage boys reported those same feelings. “No one is doing well,” says psychologist Kathleen Ethier. She heads the U.S. Centers for Disease Control and Prevention’s Division of Adolescent and School Health, which has overseen this biennial Youth Risk Behavior Survey since 1991. During the latest round of data collection, in fall 2021, over 17,000 students from 31 states responded to roughly 100 questions related to mental health, suicidal thoughts and behaviors, sexual behavior, substance use and experiences of violence. One chart in particular garnered considerable media attention. From 2011 to 2021, persistent sadness or hopelessness in boys went up 8 percentage points, from 21 to 29 percent. In girls, it rose a whopping 21 percentage points, from 36 to 57 percent. Some of that disparity may arise from the fact that girls in the United States face unique stressors, researchers say. Compared with boys, girls seem more prone to experiencing mental distress from social media use, are more likely to experience sexual violence and are dealing with a political climate that is often hostile to women’s rights (SN: 7/16/22 & 7/30/22, p. 6). But the gap between boys and girls might not be as wide as the numbers indicate. Depression manifests differently in boys and men than in girls and women, mounting evidence suggests. Girls are more likely to internalize feelings, while boys are more likely to externalize them. Rather than crying when feeling down, for instance, boys may act irritated or lash out. Or they may engage in risky, impulsive or even violent acts. Inward-directed terms like “sadness” and “hopelessness” miss those more typically male tendencies. And masculine norms that equate sadness with weakness may make males who are experiencing those emotions less willing to admit it, even on an anonymous survey. © Society for Science & the Public 2000–2023

Keyword: Depression; Development of the Brain
Link ID: 28841 - Posted: 07.01.2023