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By Laura Sanders It’s a bit like seeing a world in a grain of sand. Except the view, in this case, is the exquisite detail inside a bit of human brain about half the size of a grain of rice. Held in that minuscule object is a complex collective of cells, blood vessels, intricate patterns and biological puzzles. Scientists had hints of these mysteries in earlier peeks at this bit of brain (SN: 6/29/21). But now, those details have been brought into new focus by mapping the full landscape of some 57,000 cells, 150 million synapses and their accompanying 23 centimeters of blood vessels, researchers report in the May 10 Science. The full results, the scientists hope, may lead to greater insights into how the human brain works. “We’re going in and looking at every individual connection attached to every cell — a very high level of detail,” says Viren Jain, a computational neuroscientist at Google Research in Mountain View, Calif. The big-picture goal of brain mapping efforts, he says, is “to understand how human brains work and what goes wrong in various kinds of brain diseases.” The newly mapped brain sample was removed during a woman’s surgery for epilepsy, so that doctors could reach a deeper part of the brain. The bit, donated with the woman’s consent, was from the temporal lobe of the cortex, the outer part of the brain involved in complex mental feats like thinking, remembering and perceiving. This digital drawing of a person's head shows the brain inside. An arrow points to the bottom left side of the brain. After being fixed in a preservative, the brain bit was sliced into almost impossibly thin wisps, and then each slice was imaged with a high-powered microscope. Once these views were collected, researchers used computers to digitally reconstruct the three-dimensional objects embedded in the piece of brain. © Society for Science & the Public 2000–2024

Keyword: Brain imaging; Development of the Brain
Link ID: 29324 - Posted: 05.25.2024

By Jennifer Hassan More people in the United States say they are using marijuana daily or near daily, compared with people who say they are drinking alcohol that often, according to a new study. In 2022, about 17.7 million people reported daily or near-daily marijuana use, compared with 14.7 million people who reported drinking at the same frequency, said the report, which was based on more than four decades of data from the National Survey on Drug Use and Health. It was the first time the survey recorded more frequent users of cannabis than alcohol, the report added. The research was published Wednesday in the peer-reviewed journal Addiction. The research window spans the years 1979 to 2022, and the 27 surveys that were analyzed involved more than 1.6 million participants during that time frame. The study described the growth in daily or near-daily cannabis use as “striking.” While “far more people drink” than use marijuana, high-frequency drinking among Americans is less common, the report said. The 2022 survey found that the median drinker reported drinking on four to five days in a month, compared with 15 to 16 days in a month for cannabis. The study noted that changing trends in cannabis use “parallel corresponding changes in cannabis policy, with declines during periods of greater restriction and growth during periods of policy liberalization.” It stressed, however, that this did not mean there was a causal link, as “both could have been manifestations of changes in underlying culture and attitudes.” Thirty-eight states and D.C. have legalized medical marijuana programs, and 24 states have approved recreational cannabis use.

Keyword: Drug Abuse
Link ID: 29323 - Posted: 05.25.2024

By Yasemin Saplakoglu György Buzsáki first started tinkering with waves when he was in high school. In his childhood home in Hungary, he built a radio receiver, tuned it to various electromagnetic frequencies and used a radio transmitter to chat with strangers from the Faroe Islands to Jordan. He remembers some of these conversations from his “ham radio” days better than others, just as you remember only some experiences from your past. Now, as a professor of neuroscience at New York University, Buzsáki has moved on from radio waves to brain waves to ask: How does the brain decide what to remember? By studying electrical patterns in the brain, Buzsáki seeks to understand how our experiences are represented and saved as memories. New studies from his lab and others have suggested that the brain tags experiences worth remembering by repeatedly sending out sudden and powerful high-frequency brain waves. Known as “sharp wave ripples,” these waves, kicked up by the firing of many thousands of neurons within milliseconds of each other, are “like a fireworks show in the brain,” said Wannan Yang, a doctoral student in Buzsáki’s lab who led the new work, which was published in Science in March. They fire when the mammalian brain is at rest, whether during a break between tasks or during sleep. Sharp wave ripples were already known to be involved in consolidating memories or storing them. The new research shows that they’re also involved in selecting them — pointing to the importance of these waves throughout the process of long-term memory formation. It also provides neurological reasons why rest and sleep are important for retaining information. Resting and waking brains seem to run different programs: If you sleep all the time, you won’t form memories. If you’re awake all the time, you won’t form them either. “If you just run one algorithm, you will never learn anything,” Buzsáki said. “You have to have interruptions.” © 2024 the Simons Foundation.

Keyword: Learning & Memory
Link ID: 29322 - Posted: 05.23.2024

By Amanda Heidt For the first time, a brain implant has helped a bilingual person who is unable to articulate words to communicate in both of his languages. An artificial-intelligence (AI) system coupled to the brain implant decodes, in real time, what the individual is trying to say in either Spanish or English. The findings1, published on 20 May in Nature Biomedical Engineering, provide insights into how our brains process language, and could one day lead to long-lasting devices capable of restoring multilingual speech to people who can’t communicate verbally. “This new study is an important contribution for the emerging field of speech-restoration neuroprostheses,” says Sergey Stavisky, a neuroscientist at the University of California, Davis, who was not involved in the study. Even though the study included only one participant and more work remains to be done, “there’s every reason to think that this strategy will work with higher accuracy in the future when combined with other recent advances”, Stavisky says. The person at the heart of the study, who goes by the nickname Pancho, had a stroke at age 20 that paralysed much of his body. As a result, he can moan and grunt but cannot speak clearly. In his thirties, Pancho partnered with Edward Chang, a neurosurgeon at the University of California, San Francisco, to investigate the stroke’s lasting effects on his brain. In a groundbreaking study published in 20212, Chang’s team surgically implanted electrodes on Pancho’s cortex to record neural activity, which was translated into words on a screen. Pancho’s first sentence — ‘My family is outside’ — was interpreted in English. But Pancho is a native Spanish speaker who learnt English only after his stroke. It’s Spanish that still evokes in him feelings of familiarity and belonging. “What languages someone speaks are actually very linked to their identity,” Chang says. “And so our long-term goal has never been just about replacing words, but about restoring connection for people.” © 2024 Springer Nature Limited

Keyword: Language; Robotics
Link ID: 29321 - Posted: 05.23.2024

By Christina Jewett Just four months ago, Noland Arbaugh had a circle of bone removed from his skull and hair-thin sensor tentacles slipped into his brain. A computer about the size of a small stack of quarters was placed on top and the hole was sealed. Paralyzed below the neck, Mr. Arbaugh is the first patient to take part in the clinical trial of humans testing Elon Musk’s Neuralink device, and his early progress was greeted with excitement. Working with engineers, Mr. Arbaugh, 30, trained computer programs to translate the firing of neurons in his brain into the act of moving a cursor up, down and around. His command of the cursor was soon so agile that he could challenge his stepfather at Mario Kart and play an empire-building video game late into the night. But as weeks passed, about 85 percent of the device’s tendrils slipped out of his brain. Neuralink’s staff had to retool the system to allow him to regain command of the cursor. Though he needed to learn a new method to click on something, he can still skate the cursor across the screen. Neuralink advised him against a surgery to replace the threads, he said, adding that the situation had stabilized. The setback became public earlier this month. And although the diminished activity was initially difficult and disappointing, Mr. Arbaugh said it had been worth it for Neuralink to move forward in a tech-medical field aimed at helping people regain their speech, sight or movement. “I just want to bring everyone along this journey with me,” he said. “I want to show everyone how amazing this is. And it’s just been so rewarding. So I’m really excited to keep going.” From a small desert town in Arizona, Mr. Arbaugh has emerged as an enthusiastic spokesman for Neuralink, one of at least five companies leveraging decades of academic research to engineer a device that can help restore function in people with disabilities or degenerative diseases. © 2024 The New York Times Company

Keyword: Robotics
Link ID: 29320 - Posted: 05.23.2024

By Claudia López Lloreda Fentanyl’s powerful pull comes from both the potent, rapid euphoria people feel while on the drug and the devastating symptoms of withdrawal. Researchers have now zeroed in on brain circuits responsible for these two forces of fentanyl addiction. The study in mice, reported May 22 in Nature, suggests two distinct brain pathways are in play. “Addiction is not a simple disorder — it’s very complex and dynamic,” says Mary Kay Lobo, a neuroscientist at the University of Maryland School of Medicine in Baltimore who was not involved with the new research. She appreciates that the study looks not only at reward in the brain, but also at the withdrawal symptoms, which are “this dark side of addiction.” Fentanyl and other synthetic opioids are highly addictive (SN: 4/28/23). About one of every four fentanyl users becomes addicted. And in 2022 in the United States alone, there were more than 70,000 deaths from synthetic opioid overdoses, primarily fentanyl. Researchers have known that dopamine-releasing neurons in an area of the midbrain called the ventral tegmental area, or VTA, mediate feelings like euphoria. But the circuits driving withdrawal symptoms were less clear. Such symptoms include nausea, pain, irritability and an inability to feel pleasure. To find out more, neuroscientist Christian Lüscher of the University of Geneva and colleagues injected mice with fentanyl for three consecutive days then stopped, inducing withdrawal by giving the mice naloxone. © Society for Science & the Public 2000–2024.

Keyword: Drug Abuse
Link ID: 29319 - Posted: 05.23.2024

By Christina Caron Just before Katie Marsh dropped out of college, she began to worry that she might have attention deficit hyperactivity disorder. “Boredom was like a burning sensation inside of me,” said Ms. Marsh, who is now 30 and lives in Portland, Ore. “I barely went to class. And when I did, I felt like I had a lot of pent-up energy. Like I had to just move around all the time.” So she asked for an A.D.H.D. evaluation — but the results, she was surprised to learn, were inconclusive. She never did return to school. And only after seeking help again four years later was she diagnosed by an A.D.H.D. specialist. “It was pretty frustrating,” she said. A.D.H.D. is one of the most common psychiatric disorders in adults. Yet many health care providers have uneven training on how to evaluate it, and there are no U.S. clinical practice guidelines for diagnosing and treating patients beyond childhood. Without clear rules, some providers, while well-intentioned, are just “making it up as they go along,” said Dr. David W. Goodman, an assistant professor of psychiatry and behavioral sciences at the Johns Hopkins University School of Medicine. This lack of clarity leaves providers and adult patients in a bind. “We desperately need something to help guide the field,” said Dr. Wendi Waits, a psychiatrist with Talkiatry, an online mental health company. “When everyone’s practicing somewhat differently, it makes it hard to know how best to approach it.” Can A.D.H.D. symptoms emerge in adulthood? A.D.H.D. is defined as a neurodevelopmental disorder that begins in childhood and is typically characterized by inattention, disorganization, hyperactivity and impulsivity. Patients are generally categorized into three types: hyperactive and impulsive, inattentive, or a combination of the two. © 2024 The New York Times Company

Keyword: ADHD
Link ID: 29318 - Posted: 05.23.2024

By Ellen Barry The annual gathering of the American Psychiatric Association is a dignified and collegial affair, full of scholarly exchanges, polite laughter and polite applause. So it was a shock, for those who took their seats in Room 1E08 of the Jacob K. Javits Convention Center in Manhattan, to watch a powerfully built 32-year-old man choke back tears as he described being slammed to the floor and cuffed to a stretcher in a psychiatric unit. Because the man, Matthew Tuleja, had been a Division I football player, he had a certain way of describing the circle of bodies that closed around him, the grabbing and grappling and the sensation of being dominated, pinned and helpless. He was on the ground in a small room filled with pepper spray. Then his wrists and ankles were cuffed to the sides of a stretcher, and his pants were yanked down. They gave him injections of Haldol, an antipsychotic medication he had repeatedly tried to refuse, as he howled in protest. Forcible restraints are routine events in American hospitals. One recent study, using 2017 data from the Centers for Medicare and Medicaid Services, estimated the number of restraints per year at more than 44,000. But it is rare to hear a first-person account of the experience, because it tends to happen to people who do not have a platform. Researchers who surveyed patients about restraint and seclusion have found that a large portion, 25 to 47 percent , met criteria for post-traumatic stress disorder. Listening, rapt, to Mr. Tuleja was a roomful of psychiatrists. It was a younger crowd — people who had entered the field at the time of the Black Lives Matter protests. Many of them lined up to speak to him afterward. “I still can’t forget the first time I saw someone restrained,” one doctor told him. “You don’t forget that.” © 2024 The New York Times Company

Keyword: Schizophrenia; Aggression
Link ID: 29317 - Posted: 05.21.2024

By Meghan Willcoxon In the summer of 1991, the neuroscientist Vittorio Gallese was studying how movement is represented in the brain when he noticed something odd. He and his research adviser, Giacomo Rizzolatti, at the University of Parma were tracking which neurons became active when monkeys interacted with certain objects. As the scientists had observed before, the same neurons fired when the monkeys either noticed the objects or picked them up. But then the neurons did something the researchers didn’t expect. Before the formal start of the experiment, Gallese grasped the objects to show them to a monkey. At that moment, the activity spiked in the same neurons that had fired when the monkey grasped the objects. It was the first time anyone had observed neurons encode information for both an action and another individual performing that action. Those neurons reminded the researchers of a mirror: Actions the monkeys observed were reflected in their brains through these peculiar motor cells. In 1992, Gallese and Rizzolatti first described the cells in the journal Experimental Brain Research and then in 1996 named them “mirror neurons” in Brain. The researchers knew they had found something interesting, but nothing could have prepared them for how the rest of the world would respond. Within 10 years of the discovery, the idea of a mirror neuron had become the rare neuroscience concept to capture the public imagination. From 2002 to 2009, scientists across disciplines joined science popularizers in sensationalizing these cells, attributing more properties to them to explain such complex human behaviors as empathy, altruism, learning, imitation, autism, and speech. Then, nearly as quickly as mirror neurons caught on, scientific doubts about their explanatory power crept in. Within a few years, these celebrity cells were filed away in the drawer of over-promised, under-delivered discoveries. © 2024 NautilusNext Inc.,

Keyword: Attention; Vision
Link ID: 29316 - Posted: 05.21.2024

Ian Sample Science editor A device that stimulates the spinal nerves with electrical pulses appears to boost how well people recover from major spinal cord injuries, doctors say. An international trial found that patients who had lost some or all use of their hands and arms after a spinal cord injury regained strength, control and sensation when the stimulation was applied during standard rehabilitation exercises. The improvements were small but were described by doctors and patients as life-changing because of the impact they had on the patients’ daily routines and quality of life. “It actually makes it easier for people to move, including people who have complete loss of movement in their hands and arms,” said Prof Chet Moritz, in the department of rehabilitation medicine at the University of Washington in Seattle. “The benefits accumulate gradually over time as we pair this spinal stimulation with intensive therapy of the hands and arms, such that there are benefits even when the stimulator is turned off.” Rather than being implanted, the Arc-Ex device is worn externally and uses electrodes that are placed on the skin near the section of the spinal cord responsible for controlling a particular movement or function. The researchers believe that electrical stimulation helps nerves that remain intact after the injury to send signals and ultimately partially restore some communication between the brain and paralysed body part. More than half of patients who suffer spinal cord injuries still have some intact nerves that cross the injury site. © 2024 Guardian News & Media Limited

Keyword: Robotics; Movement Disorders
Link ID: 29315 - Posted: 05.21.2024

By Matt Richtel With weed these days, it’s a Willy Wonka world: chocolate bars, lollipops, exotic-flavored gummies — to say nothing of joints, vapes, drinks and the rest. Twenty-four states and the District of Columbia have now legalized the sale of marijuana for recreational use, prompting innovation, lowering prices and making the drug — more potent than ever — more widely available. The Biden administration this week recommended easing the federal regulations on cannabis. What does all of this mean for adolescents? Studies have demonstrated that marijuana use can harm the developing brain. Some new strains have been linked to psychosis. Many health experts have worried that relaxing the laws around cannabis will lead to more use of the drug among minors. But Rebekah Levine Coley, a developmental psychologist at Boston College, is less certain. In April, she and colleagues published a study in JAMA that examined drug use patterns among 900,000 high school students from 2011 to 2021, using self-reported data from the Youth Risk Behavior Survey. They found that fewer minors reported having used cannabis in the previous month in states where the drug had been legalized. But they also found that in the 18 states that had both legalized cannabis and allowed retail sales of the drug, some adolescents who were users of the drug used it more frequently. The net effect was a flat or slight decline in cannabis use among adolescents. Dr. Coley spoke to The New York Times about the study, and its implications for state and federal drug policy. This conversation has been edited and condensed for clarity. It seems sensible to assume that legalizing marijuana would lead to more use by young people. Yes, common sense might argue that as cannabis becomes legalized, it will be more accessible. There will be fewer potential legal repercussions, hence availability would increase and use would increase. © 2024 The New York Times Company

Keyword: Drug Abuse
Link ID: 29314 - Posted: 05.21.2024

By Laura Sanders Everyone knows that the brain influences the heart. Stressful thoughts can set the heart pounding, sometimes with such deep force that we worry people can hear it. Anxiety can trigger the irregular skittering of atrial fibrillation. In more extreme and rarer cases, emotional turmoil from a shock — the death of a loved one, a cancer diagnosis, an intense argument — can trigger a syndrome that mimics a heart attack. But not everyone knows that the heart talks back. Subscribe to Science News Powerful signals travel from the heart to the brain, affecting our perceptions, decisions and mental health. And the heart is not alone in talking back. Other organs also send mysterious signals to the brain in ways that scientists are just beginning to tease apart. A bodywide perspective that seeks to understand our biology and behavior is relatively new, leaving lots of big, basic questions. The complexities of brain-body interactions are “only matched by our ignorance of their organization,” says Peter Strick, a neuroscientist at the University of Pittsburgh. Exploring the relationships between the heart, other organs and the brain isn’t just fascinating anatomy. A deeper understanding of how we sense and use signals from inside our bodies — a growing field called interoception — may point to new treatments for disorders such as anxiety. “We have forgotten that interactions with the internal world are probably as important as interactions with the external world,” says cognitive neuroscientist Catherine Tallon-Baudry of École Normale Supérieure in Paris. © Society for Science & the Public 2000–2024.

Keyword: Emotions; Depression
Link ID: 29313 - Posted: 05.18.2024

By Angie Voyles Askham Some questions about neurons, such as how they give rise to behavior, are tricky to answer when those cells are embedded within their natural milieu. “Is residence in a nervous system sufficient to allow synapses to form?” says Kristin Baldwin, professor of genetics and development at Columbia University. “Are synapses that we can see sufficient to allow communication? And is synaptic communication sufficient to actually endow an animal with a set of behaviors that would be appropriate for it?” The best way to answer those questions is to put the cells in a new environment where their extrinsic and intrinsic influences can be teased apart, says Xin Jin, assistant professor of neuroscience at the Scripps Research Institute. For a long time, Jin says, that new environment was the unnatural setting of a petri dish. But two new studies that make use of chimeric mice—animals with both mouse and rat cells in their brain—point to another option: One demonstrates how rat stem cells can restore a mouse’s ability to smell, whereas the other shows how rat stem cells can give rise to a forebrain in mice that would otherwise lack one. The studies were published last month in Cell. Because rat brains are larger than mouse brains and develop at a different rate, the chimeras enable researchers to probe the competing forces of a cell’s intrinsic programming and its external environment. The work opens up doors for new research and the ability to explore the origins of species-specific cellular behaviors, says Jin, who was not involved in either study. “It’s sort of a fundamental ‘nature versus nurture,’” says Baldwin, who led one of the new studies. © 2024 Simons Foundation

Keyword: Development of the Brain
Link ID: 29312 - Posted: 05.18.2024

By Meghan Rosen An experimental weight loss procedure cranks up the heat to dial down hunger. Blasting a patch of patients’ stomach lining with thermal energy curbed hunger and cut pounds, researchers reported in a small pilot study to be presented at the annual Digestive Disease Week meeting on May 19 in Washington, D.C. Called gastric fundus mucosal ablation, the procedure relies on an endoscope, a thin tube that can be threaded down the throat. It takes less than an hour and doesn’t require hospitalization. “The advantage of this is that it’s a relatively straightforward procedure,” says Cleveland Clinic surgical endoscopist Matthew Kroh, who was not involved with the work. Side effects, which included mild nausea and cramping, are minimal, one study author said in a news conference on May 8. That’s a big difference from bariatric surgery, considered the gold standard treatment for obesity, which includes many techniques to restrict stomach size or affect food absorption. Patients can be hospitalized for days and take weeks to recover. Obese people often avoid these treatments because they don’t want to endure surgery, Kroh says. The new procedure could one day offer an easier option — if the results hold up in larger groups of patients. “There’s potential,” Kroh says, “but I think we have to be cautious.” The trial included 10 women, so the method is still at the proof-of-concept stage. On average, the women lost nearly 8 percent of their body weight, some 19 pounds, over six months. That’s less than patients typically see from bariatric surgery or pharmaceutical treatments like the anti-obesity drug Wegovy (SN 12/13/23). © Society for Science & the Public 2000–2024.

Keyword: Obesity; Hormones & Behavior
Link ID: 29311 - Posted: 05.18.2024

By Jordan Pearson Engineers and scientists have an enduring fascination with spider silk. Similar to typical worm silk that makes for comfy bedsheets, but much tougher, the material has inspired the invention of lighter and more breathable body armor and materials that could make airplane components stronger without adding weight. Researchers are even using examples drawn from spider webs to design sensitive microphones that can one day be used to treat hearing loss and deafness and to improve other listening devices. Spiders use their webs like enormous external eardrums. A team of scientists from Binghamton University and Cornell University reported in 2022 that webs allow arachnids to detect sound from 10 feet away. When you hear a sound through your ear, what you’re really experiencing are changes in air pressure that cause your eardrum to vibrate. This is how microphones work: by mimicking the human ear and vibrating in response to pressure. Instead of vibrating when hit by a wave of pressure like a stick hitting a drumhead, they move with the flow of the air being displaced. Air is a fluid medium “like honey,” said Ronald Miles, a professor of mechanical engineering at Binghamton. Humans navigate this environment without noticing much resistance, but silk fibers are buffeted about by the velocity of the viscous forces in air. Dr. Miles couldn’t help but wonder if this principle could lead to a new kind of microphone. “Humans are kind of arrogant animals,” he said. “They make devices that work like they do.” But he wondered about building a device to be more like a spider and sense “sound with the motion of the air.” © 2024 The New York Times Company

Keyword: Hearing
Link ID: 29310 - Posted: 05.18.2024

By Kermit Pattison Since the Stone Age, hunters have brought down big game with spears, atlatls, and bows and arrows. Now, a new study reveals traditional societies around the globe also relied on another deadly but often-overlooked weapon: our legs. According to a report published today in Nature Human Behaviour, running down big game such as antelope, moose, and even kangaroos was far more widespread than previously recognized. Researchers documented nearly 400 cases of endurance pursuits—a technique in which prey are chased to exhaustion—by Indigenous peoples around the globe between the 16th and 21st centuries. And in some cases, they suggest, it can be more efficient than stealthy stalking. The findings bolster the idea that humans evolved to be hunting harriers, says Daniel Lieberman, an evolutionary biologist at Harvard University. “Nobody else has come up with any other explanation for why humans evolved to run long distances,” says Lieberman, who adds that he’s impressed with the paper’s “depth of scholarship.” For decades, some anthropologists have argued that endurance running was among the first hunting techniques employed by early hominins in Africa. Advocates suggest subsequent millennia spent chasing down prey shaped many unique human features, including our springy arched feet, slow-twitch muscle fibers optimized for efficiency, heat-shedding bare skin, and prodigious ability to sweat. The “born to run” idea has become something of an origin story among many endurance athletes. But a pack of skeptics has dogged the theory. Critics cited the higher energetic costs of running over walking and noted that accounts of persistence hunting among modern foragers are rare. Yet hints of such pursuits kept popping up as Eugène Morin, an archaeologist at Trent University and co-author of the new paper, scoured the literature for a book he was writing on hunting among traditional societies. As he pored over early accounts by missionaries, travelers, and explorers, he repeatedly found descriptions of long-distance running and tracking. © 2024 American Association for the Advancement of Science.

Keyword: Evolution
Link ID: 29309 - Posted: 05.16.2024

By Jake Buehler Sounding like a toxic moth might keep some beetles safe from hungry bats. When certain tiger beetles hear an echolocating bat draw near, they respond with extremely high-pitched clicks. This acoustic countermeasure is a dead ringer for the noises toxic moths make to signal their nasty taste to bats, researchers report May 15 in Biology Letters. Such sound-based mimicry may be widespread among groups of night-flying insects, the scientists say. At night, bats and bugs are locked in sonic warfare. At least seven major insect groups have ears sensitive to bat echolocation pitches, and many often flee in response. Some moths have sound-absorbent wings and fuzz that impart stealth against bat sonar (SN: 11/14/18). Others use their genitals to make ultrasonic trills — above the range of human hearing — that may startle bats or jam their sonar (SN: 7/3/13). Previous research suggested some tiger beetles — a family of fast-running, often strikingly colored predatory beetles with strong jaws — also make high-pitched clicks as a response to human-made imitations of bat ultrasound. So Harlan Gough, a conservation entomologist now at the U.S. Fish and Wildlife Service in Burbank, Wash., and his colleagues set out to answer why. The researchers collected 19 tiger beetle species from southern Arizona and brought them into the lab. They tethered the insects to a metal rod and prompted them to fly. The team then filmed and recorded audio to see how the beetles responded to playback of a bat clicking sequence that immediately precedes an attack. Right away, seven of these species — all nocturnal fliers — pulled their hard, case-like forewings into the path of their beating hindwings. The resulting collisions made high-pitched clicking noises. © Society for Science & the Public 2000–2024.

Keyword: Hearing; Evolution
Link ID: 29308 - Posted: 05.16.2024

By Asher Mullard With obesity drugs now helping people to slim down, researchers are working to capitalize on their popularity by bulking up the weight-loss drug pipeline. The latest contender takes a Trojan horse approach — hiding a small molecule in a gut-hormone-mimicking peptide already used in obesity drugs — to strike a double blow to the brain cells that control appetite. The new work, which demonstrated the effects of this drug candidate in mice and rats, was published today in Nature1. “It’s a strong paper,” says Daniel Drucker, an endocrinologist at Mount Sinai Hospital in Toronto, Canada, who helped to unravel the role of gut hormones such as GLP-1 (glucagon-like peptide-1) and GIP (glucose-dependent insulinotropic polypeptide) in obesity. The blockbuster weight-loss drugs semaglutide (Wegovy) and tirzepatide (Zepbound) act by mimicking these hormones, binding to their receptors on neurons in the brain that control hunger pangs. These drugs can help people to lose 15–20% of their body weight. And it could be possible to eke even more activity from these hormone mimics by fusing them to other drugs, the new study suggests. “Very high marks for the novelty” of the research, says Drucker, who was not involved and consults for the pharmaceutical industry. “Let’s hope that we’ll see some proof of concept in the clinic”, when the approach is tested in humans. Trojan therapeutics The drug contender takes aim at both the GLP-1 receptor and the NMDA receptor, an ion channel found on cells in the brain that was linked to obesity in 20152. At the time, small molecules that blocked the NMDA receptor seemed like a non-starter for obesity-drug developers, because this type of compound, which includes the party drug and antidepressant ketamine, is riddled with harmful side effects. But Christoffer Clemmensen, a metabolism specialist at the University of Copenhagen, saw a path forwards. He speculated that it might be possible to sidestep the safety risks by fusing an NMDA-receptor blocker to a gut-hormone mimic that acts only on the neurons that regulate appetite. © 2024 Springer Nature Limited

Keyword: Obesity
Link ID: 29307 - Posted: 05.16.2024

By Emily Anthes Half a century ago, one of the hottest questions in science was whether humans could teach animals to talk. Scientists tried using sign language to converse with apes and trained parrots to deploy growing English vocabularies. The work quickly attracted media attention — and controversy. The research lacked rigor, critics argued, and what seemed like animal communication could simply have been wishful thinking, with researchers unconsciously cuing their animals to respond in certain ways. In the late 1970s and early 1980s, the research fell out of favor. “The whole field completely disintegrated,” said Irene Pepperberg, a comparative cognition researcher at Boston University, who became known for her work with an African gray parrot named Alex. Today, advances in technology and a growing appreciation for the sophistication of animal minds have renewed interest in finding ways to bridge the species divide. Pet owners are teaching their dogs to press “talking buttons” and zoos are training their apes to use touch screens. In a cautious new paper, a team of scientists outlines a framework for evaluating whether such tools might give animals new ways to express themselves. The research is designed “to rise above some of the things that have been controversial in the past,” said Jennifer Cunha, a visiting research associate at Indiana University. The paper, which is being presented at a science conference on Tuesday, focuses on Ms. Cunha’s parrot, an 11-year-old Goffin’s cockatoo named Ellie. Since 2019, Ms. Cunha has been teaching Ellie to use an interactive “speech board,” a tablet-based app that contains more than 200 illustrated icons, corresponding to words and phrases including “sunflower seeds,” “happy” and “I feel hot.” When Ellie presses on an icon with her tongue, a computerized voice speaks the word or phrase aloud. In the new study, Ms. Cunha and her colleagues did not set out to determine whether Ellie’s use of the speech board amounted to communication. Instead, they used quantitative, computational methods to analyze Ellie’s icon presses to learn more about whether the speech board had what they called “expressive and enrichment potential.” © 2024 The New York Times Company

Keyword: Language; Epilepsy
Link ID: 29306 - Posted: 05.14.2024

By Lee Alan Dugatkin 1 The complexity of animal social behavior is astonishing I have studied animal behavior for more than 35 years, so I’m rarely surprised at just how nuanced, subtle, and complex the social behavior of nonhuman animals can be. But, every once in a while, that “my goodness, how astonishing!” feeling—which I felt so often in graduate school—returns. That’s how I felt when I read Kevin Oh and Alexander Badyaev’s work on sexual selection and social networks in house finches (Haemorhous mexicanus). The house finches in question, I learned while researching my book, live on the campus of the University of Arizona, where, in 2003, Oh was doing his graduate work and Badyaev was a young assistant professor. Using data on thousands of finches they banded over six years, these two researchers were able to map the social network the birds relied on during breeding season. This network was composed of 25 “neighborhoods” with an average of 30 finches per group. Females rarely left their neighborhoods to interact with birds in other neighborhoods. But how much males moved around from one neighborhood to the next depended on their coloring. Those with plenty of red coloration—which females tend to prefer as mating partners—generally remained put, just like females. But drabber colored males were more likely to socialize across many neighborhoods. The question was why? The answer was what rekindled my own sense of awe in the power of natural selection to shape animal social behavior. When Oh and Bedyaev mapped reproductive success in their house finches, they found that the most colorful males did well no matter what neighborhood they were in. Drab males, however, had greater reproductive success if they tried their luck all around town—essentially, this allowed them to find just the spot where their relative coloration was greatest and therefore most likely to score them a mate. In other words, they learned to play the field, restructuring social networks in a way that served their purposes best. 2 Technology is radically changing how scientists study the behavior of animals © 2024 NautilusNext Inc.,

Keyword: Learning & Memory; Evolution
Link ID: 29305 - Posted: 05.14.2024