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By Jake Buehler A light crackling sound floats above a field in northern Switzerland in late summer. Its source is invisible, tucked inside a dead, dried plant stem: a dozen larval mason bees striking the inner walls of their herbaceous nest. While adult bees and wasps make plenty of buzzy noises, their young have generally been considered silent. But the babies of at least one bee species make themselves heard, playing percussion instruments growing out of their faces and rear ends, researchers report February 25 in the Journal of Hymenoptera Research. The larvae’s chorus of tapping and rasping may be a clever strategy to befuddle predatory wasps. Unlike honeybees, the mason bee (Hoplitis tridentata) lives a solitary life. Females chew into dead plant stems and lay their eggs inside, often in a single row of chambers lined up along its length. After hatching, the larvae feed on a provision of pollen left by the mom, spin a cocoon and overwinter as a pupa inside the stem. Andreas Müller, an entomologist at the nature conservation research agency Natur Umwelt Wissen GmbH in Zurich, has been studying bees in the Osmiini tribe, which includes mason bees and their close relatives, for about 20 years. Noticing that H. tridentata populations have been declining in northern Switzerland, he and colleague Martin Obrist tried to help the bees. “We offered the bees bundles of dry plant stems as nesting sites, and when we checked the bundles we heard the larval sounds for the first time,” says Müller. “This is a new phenomenon not only in the osmiine bees, but in bees in general.” He and Obrist, a biologist at the Swiss Federal Institute for Forest, Snow and Landscape Research in Birmensdorf, gathered stem nests from the field and subjected them to various types of physical disturbance, trying to determine what kinds of pestering triggers the bee larvae to drum. In some nests, the duo cut windows into the stems to observe larvae through the translucent cocoon walls, unveiling the secret of how the insects were creating the noises. © Society for Science & the Public 2000–2021.

Keyword: Animal Communication; Language
Link ID: 27737 - Posted: 03.17.2021

By Christa Lesté-Lasserre If you’ve ever counted to three before jumping into the pool with a friend, you’ve got something in common with dolphins. The sleek marine mammals use coordinated clicks and whistles to tell each other the precise moment to perform a backflip or push a button, according to new research. That makes them the only animals besides humans known to cooperate with vocal cues. The new work is “fascinating,” says Richard Connor, a cetacean biologist at the University of Massachusetts, Dartmouth, who was not involved with the research. “We just see so much cooperation and synchrony [among dolphins] in the wild. This helps us understand how they accomplish that.” Free-roaming dolphins are often in sync. They hunt in large groups and drive away rivals with coordinated displays. They can even match others’ movements down to their breathing patterns. But how do they achieve such synchronicity? Scientists have long suspected the cetaceans coordinate their actions through vocal cues. Underwater microphones, called hydrophones, have been picking up their whistles and clicks for decades. But dolphins don’t open their mouths when they “talk,” and tracking underwater sound has long been a technical challenge. So scientists have been developing ways to capture those sounds. In France, researchers recently combined five hydrophones to set up a star-shaped pattern that can pinpoint which dolphin in a group is “speaking,” says ethologist Juliana Lopez-Marulanda of Paris-Saclay University who co-developed the approach. © 2021 American Association for the Advancement of Science.

Keyword: Animal Communication; Language
Link ID: 27736 - Posted: 03.17.2021

By Lisa Sanders, M.D. The 35-year-old man rose abruptly from the plastic chair in the waiting room at the Health Sciences Center Emergency Department in Winnipeg, Manitoba. He lurched toward the door, arms held stiffly before him as if warding off something only he could see. “I gotta get out of here,” he muttered. His eyes looked unfocused as he glanced at the family he didn’t seem to recognize. His mother hurried to his side. “It’s OK, Sean,” she murmured in his ear. “We’re here with you.” She took him over to his seat. And then, just as suddenly, he was back to normal, back to the man his family knew and loved. This was why Sean was in the E.D. that day. He had been completely healthy until the day before, when his brother-in-law found him wandering through the house, confused. He didn’t seem to know where he was, or even who he was. But by the time the ambulance reached the community hospital near their home, the confusion had cleared, and he seemed fine. The doctors in the E.D. ordered a few tests and, when they were unrevealing, sent him home. Only a few hours later, it happened again. That’s when they brought him here, to the biggest hospital in the city. By the time they arrived, the bizarre episode had subsided. A second attack in the waiting room lasted only a few minutes, so when the E.D. doctors saw him, he was fine. These doctors also wanted to send him home, but the mother was adamant. Her 30-year-old daughter, Andrea, was admitted to another hospital in the city just three months earlier. Andrea had episodes of confusion, too. And she died in that hospital 12 days later. No one understood what her daughter had or why she died, the mother told the doctors. She wasn’t about to let the same thing happen to her son. Re-enacting His Sister’s Symptoms? And so Sean was admitted for observation. Over the next two days, he had many of these strange episodes. He would try to leave the unit. He wouldn’t answer questions; he didn’t even seem to hear them. He looked afraid. And then it would be over. He was seen by specialists in internal medicine and neurology. He had an M.R.I., a spinal tap and many blood tests. When none of those tests provided an answer, the doctors worried that he had been so emotionally traumatized by his sister’s sudden death that he developed psychological symptoms, something known as conversion disorder. He was transferred to the psychiatric unit for further evaluation. © 2021 The New York Times Company

Keyword: Development of the Brain
Link ID: 27735 - Posted: 03.17.2021

Greg Rosalsky Last month, New Jersey Governor Phil Murphy signed three bills making it official: marijuana will soon be growing legally in the gardens of the Garden State for anyone over 21 to enjoy. The bills follow through on a marijuana legalization ballot initiative that New Jerseyans approved overwhelmingly last year. New Jersey is now one of a dozen states, plus the District of Columbia, which have let loose the magic dragon — and more states, like Virginia, may be on the way. It's been almost a decade since Colorado and Washington legalized marijuana. That's given economists and other researchers enough time to study the effects of the policy. Here are some of the most interesting findings: Legalization didn't seem to substantially affect crime rates — Proponents of legalizing weed claimed it would reduce violent crimes. Opponents said it would increase violent crimes. A study by the CATO Institute finds, "Overall, violent crime has neither soared nor plummeted in the wake of marijuana legalization." Legalization seems to have little or no effect on traffic accidents and fatalities — Opponents of marijuana legalization argued it would wreak havoc on the road. A few studies have found that's not the case. Economists Benjamin Hansen, Keaton S. Miller & Caroline Weber, for instance, found evidence suggesting it had no effect on trends in traffic fatalities in both Colorado and Washington. © 2021 npr

Keyword: Drug Abuse
Link ID: 27734 - Posted: 03.17.2021

By Penelope Green In 1999, Rosalind D. Cartwright, a renowned sleep researcher, testified for the defense in the murder trial of a man who arose from his bed early one night, gathered up tools to fix his pool’s filter pump, stabbed his beloved wife to death, rolled her into the pool and went back to bed. When he was awakened by the police, he said he had no memory of his actions. His lawyers argued that the man, who had no motive to kill his wife, had been sleepwalking and was therefore in an unconscious state and not responsible for his behavior. Dr. Cartwright, who had successfully served as a witness for the defense in a similar case a decade earlier (working pro bono in both trials), agreed. The jury did not, and the man was sentenced to life in prison. As Dr. Cartwright was leaving the courtroom, however, a bailiff asked for her business card. Abashedly, he told her, “I beat people up in my sleep.” Nicknamed the Queen of Dreams by her peers, Dr. Cartwright studied the role of dreaming in divorce-induced depression, worked with sleep apnea patients and their frustrated spouses, and helped open one of the first sleep disorder clinics. She died at 98 on Jan. 15 at her home in Chicago. Her daughter, Carolyn Cartwright, said the cause was a heart attack. The earlier sleepwalking murder case that hinged on Dr. Cartwright’s testimony was a notorious one, even inspiring a television movie, “The Sleepwalker Killing”: In 1987 a young Canadian man murdered his mother-in-law and brutally attacked his father-in-law after driving from his home to theirs in his pajamas. Like the pool man, he had no motive to kill them. © 2021 The New York Times Company

Keyword: Sleep
Link ID: 27733 - Posted: 03.17.2021

Alexandra Jones In the summer of 1981, when he was 13, Grant crashed a trail motorbike into a wall at his parents’ house in Cambridgeshire. He’d been hiding it in the shed, but “it was far too powerful for me, and on my very first time starting it in the garden, I smashed it into a wall”. His mother came outside to find the skinny teenager in a heap next to the crumpled motorbike. “I was in a lot of trouble.” Grant hadn’t given this childhood memory much thought in the intervening years, but one hot August day in 2019, it came back to him with such clarity that, at 53, now a stocky father of two, he suddenly understood it as a clue to his dangerously unhealthy relationship with alcohol. The day before, a team of specialists at the Royal Devon and Exeter hospital had given him an intravenous infusion of ketamine, a dissociative hallucinogen, in common use as an anaesthetic since the 1970s, and more recently one of a group of psychedelic drugs being hailed as a silver bullet in the fight to save our ailing mental health. To date, more than 100 patients with conditions as diverse as depression, PTSD and addiction have been treated in research settings across the UK, using a radical new intervention that combines psychedelic drugs with talking therapy. What was once a fringe research interest has become the foundation of a new kind of healthcare, one that, for the first time in modern psychiatric history, purports to not only treat but actually cure mental ill health. And if advocates are to be believed, that cure will be available on the NHS within the next five years. © 2021 Guardian News & Media Limited

Keyword: Depression; Drug Abuse
Link ID: 27732 - Posted: 03.13.2021

By Rachel Nuwer The ability to link language to the world around us is a crowning feature of our species. For very young infants, it is not yet about learning the meaning of words like “cat” or “dog.” Rather, the acoustic signals in speech help foster infants' fundamental cognitive capacities, including the formation of categories of objects, such as cats or dogs. The sounds that activate this key step in development can come not just from human language but also from vocalizations made by nonhuman primates. A new study shows that babies do not use just any natural sound to build cognition, however. While primate calls and human language pass the test, birdsongs do not. “By tracing the link from language to cognition and how it’s built up with babies’ experiences with objects in the world, we get to see what are the components of this quintessential human ability to go beyond the here and now,” says Sandra Waxman, a developmental scientist at Northwestern University and senior author of the findings, which were published today in PLOS ONE. “Asking how broad that earliest link is helps to answer questions about our evolutionary legacy.” By three or four months of age, infants can categorize objects—from toys and food to pets and people—based on commonalities those objects share. This ability is boosted if the objects are presented while the infants are listening to language. The new findings build on previous work Waxman and her colleagues conducted about which sounds outside of the realm of human speech support infants’ ability to categorize objects. In past studies, they found that sequences of pure tones and backward speech do not help infants under six months of age to categorize objects, whereas listening to vocalizations from nonhuman primates—specifically, lemurs—does..” © 2021 Scientific American,

Keyword: Development of the Brain; Language
Link ID: 27731 - Posted: 03.13.2021

Neuroskeptic A new paper published in Nature Medicine reveals the wide variety of emotional experiences that can be triggered by electrical stimulation of the brain. Authors Katherine W. Scangos and colleagues tell how they implanted a single patient with 10 electrodes in different parts of the limbic system. The patient, a 36-year-old woman, had a history of severe depression, and was currently suffering a depressive episode which had not responded to any treatments. So, she agreed to undergo experimental deep brain stimulation (DBS). Over the course of 10 days, Scangos et al. tried many different stimulation parameters across the 10 electrodes, while the patient reported what she felt. Here's the full map of the emotional responses: Stimulation could evoke a gamut of emotions, from joy and relaxation to fear and darkness. For instance, stimulation of the left amygdala produced "a good feeling, more alert", but when it came to the right amygdala, stimulation instead caused feelings of "doom and gloom, very scary". The patient reported a feeling of "apathy" leading her to comment that "a lot of idiots must live like this", following right orbitofrontal cortex (OFC) stimulation. Interestingly, stimulation of certain sites could be either pleasant or unpleasant, depending on the patient's mood at the time. For example, OFC stimulation was "positive and calming if delivered during a high/neutral arousal state, but worsened mood if delivered during a low arousal state, causing the patient to feel excessively drowsy." © 2021 Kalmbach Media Co.

Keyword: Emotions; Attention
Link ID: 27730 - Posted: 03.13.2021

Kayla Hounsell · CBC News · Sarah White has always been a 'picky eater' but says the pandemic exacerbated her difficult relationship with food. It ultimately led to a diagnosis of avoidant restrictive food intake disorder. (Eric Woolliscroft/CBC) Sarah White sets a timer to remind herself to eat. She sets it six times a day so that she eats three meals and three snacks. White says she's always been a "picky eater." But when she started working from home, her routine was interrupted and her already difficult relationship with food became dangerous. It ultimately led to an eating disorder diagnosis during the pandemic. "I had all of the time in the world to eat, but I was finding I wasn't eating nearly as much as I should have been," White, 33, said during a physically distanced interview at her Halifax apartment. "It started to feel a lot more serious than it had in the past." There's been an alarming spike in the number of people seeking help for eating disorders. The National Eating Disorder Information Centre says the volume of inquiries to its help line and online chat service has been up 100 per cent during the pandemic. "There's been literature coming out across the world really suggesting that the numbers are skyrocketing and we're trying to understand why that is," said Dr. Jennifer Couturier, principal investigator for the Canadian Consensus Panel for In May, the panel, which consists of clinicians, policymakers, parents and youth, received a $50,000 federal grant to determine how best to treat eating disorders during a pandemic, particularly in children and young adults under 25. Couturier says she feels this age group hasn't received a lot of attention when it comes to research generally. ©2021 CBC/Radio-Canada.

Keyword: Anorexia & Bulimia
Link ID: 27729 - Posted: 03.13.2021

Ariana Remmel A gene-silencing technique based on CRISPR can relieve pain in mice, according to a study1. Although the therapy is still a long way from being used in humans, scientists say it is a promising approach for squelching chronic pain that lasts for months or years. Chronic pain is typically treated with opioids such as morphine, which can lead to addiction. “It’s a real challenge that the best drugs we have to treat pain give us another disease,” says Margarita Calvo, a pain physician at the Pontifical Catholic University of Chile, in Santiago, who wasn’t involved in the research. That’s why the CRISPR-based technique is exciting, she says. Scientists are already evaluating CRISPR therapies that edit a person’s genome as treatments for blood diseases and some forms of hereditary blindness. The new version of CRISPR doesn’t edit genes directly — it stops them from being expressed — and so shouldn’t cause permanent changes, although it’s unclear how long its effects last for. Some studies estimate that a large proportion of the population in Europe and the United States — as high as 50% — experiences chronic pain2,3. This pain can become debilitating over time by limiting a person’s activity and having a negative effect on their mental health. Despite the prevalence of the condition, few options exist for providing long-term relief without side effects. Even so, doctors have been moving away from prescribing opioids owing to addiction risk, and that has pared down their options even further.

Keyword: Pain & Touch; Genes & Behavior
Link ID: 27728 - Posted: 03.13.2021

By Annie Roth A few years ago, Sayaka Mitoh, a Ph.D. candidate at Nara Women’s University in Japan, was perusing her lab’s vast collection of sea slugs when she stumbled upon a gruesome sight. One of the lab’s captive-raised sea slugs, an Elysia marginata, had somehow been decapitated. When Ms. Mitoh peered into its tank to get a better look, she noticed something even more shocking: The severed head of the creature was moving around the tank, munching algae as if there was nothing unusual about being a bodiless slug. Ms. Mitoh also saw signs that the sea slug’s wound was self-inflicted: It was as if the sea slug had dissolved the tissue around its neck and ripped its own head off. Self-amputation, known as autotomy, isn’t uncommon in the animal kingdom. Having the ability to jettison a body part, such as a tail, helps many animals avoid predation. However, no animal had ever been observed ditching its entire body. “I was really surprised and shocked to see the head moving,” said Ms. Mitoh, who studies the life history traits of sea slugs. She added that she expected the slug “would die quickly without a heart and other important organs.” But it not only continued to live, it also regenerated the entirety of its lost body within three weeks. This prompted Ms. Mitoh and her colleagues to conduct a series of experiments aimed at figuring out how and why some sea slugs guillotine themselves. The results of their experiments, published Monday in Current Biology, provide evidence that Elysia marginata, and a closely related species, Elysia atroviridis, purposefully decapitate themselves in order to facilitate the growth of a new body. Although more research is needed, the researchers suspect these sea slugs ditch their bodies when they become infected with internal parasites. © 2021 The New York Times Company

Keyword: Evolution; Development of the Brain
Link ID: 27727 - Posted: 03.11.2021

By Kelly Servick Swallowing an oxycodone pill might quiet nerves and blunt pain, but the drug makes other unwanted visits in the brain—to centers that can drive addiction and suppress breathing. Now, a study in mice shows certain types of pain can be prevented or reversed without apparent side effects by silencing a gene involved in pain signaling. If the approach weathers further testing, it could give chronic pain patients a safer and longer lasting option than opioids. “It’s a beautiful piece of work,” says Rajesh Khanna, a neuroscientist who studies pain mechanisms and potential treatments at the University of Arizona. Despite successes of gene therapy against rare and life-threatening disorders, few teams have explored genetic approaches to treating pain, he says. That’s in part because of reluctance to permanently change the genome to address conditions that, although disabling, aren’t always permanent or fatal. But the new approach doesn’t alter the DNA sequence itself and is theoretically reversible, Khanna notes. “I think this study is going to be our benchmark.” A prick of the finger or a punch in the gut causes pain because nerves branching through our bodies reach into the spinal cord to relay messages to the brain. Those messages can persist even after the initial injury has healed, causing chronic pain. To fire their electrical signals, pain-sensing nerves rely on the flow of ions across protein channels in their membranes. One such channel, called Nav1.7, stands out for the remarkable pain disorders that arise when it malfunctions. People with genetic mutations that make Nav1.7 overactive are prone to attacks of burning pain. Those with mutations that deactivate Nav1.7 feel no pain at all. © 2021 American Association for the Advancement of Science.

Keyword: Pain & Touch
Link ID: 27726 - Posted: 03.11.2021

By Branko van Hulst, Sander Werkhoven, Sarah Dursto “A rose by any other name would smell as sweet.” It is an often-used quote, and for good reason. Juliet tragically underestimated the impact of the Montague surname. She was not the first, nor the last, to underestimate the power of the names we give. In psychiatry, handbooks determine which names (or classifications) we give to the difficulties that people face. We use them so that when we say ADHD, schizophrenia or depression, people have a more or less consistent idea of what we mean. Moreover, it enables us to study groups of people with the same classification and learn about treatments and prognostics. However, a severe and often overlooked side effect of this practice is that these names implicitly suggest causality. The classificatory terms we use all refer to disorders that cause symptoms, and therefore suggest that we understand the causes of the problems. Which we do not. At the very least, the term disorder suggests a common causal structure, which goes against all our current knowledge on causal heterogeneity in psychiatry. Moreover, these classifications are applied to individuals and therefore suggest that causes lie mainly with the affected individual. The most common psychiatric handbooks (DSM-5 and ICD-11) are clear on the status of their classifications: they are purely descriptive and are not based on underlying causes. Still, in practice, we say things like “he is inattentive at school because he has ADHD.” It is a circular statement: a child is inattentive because of his inattentiveness. When we say that someone has an attention deficit, we are inclined to look for the cause of the problem. But when we say someone has an attention deficit disorder, we might wrongly assume we have already found the cause. Or, in a milder version, assume the cause to be located somewhere in the (brain of the) individual. © 2021 Scientific American,

Keyword: ADHD; Development of the Brain
Link ID: 27725 - Posted: 03.11.2021

James Doubek By being able to wait for better food, cuttlefish — the squishy sea creatures similar to octopuses and squids — showed self-control that's linked to the higher intelligence of primates. It was part of an experiment by Alex Schnell from the University of Cambridge and colleagues. "What surprised me the most was that the level of self-control shown by our cuttlefish was quite advanced," she tells Lulu Garcia-Navarro on Weekend Edition. The experiment was essentially a take on the classic "marshmallow" experiment from the 1960s. In that experiment, young children were presented with one marshmallow and told that if they can resist eating it, unsupervised, for several minutes, they will get two marshmallows. But if they eat it that's all they get. The conventional wisdom has been that children who are able to delay gratification do better on tests and are more successful later in life. (There are of course many caveats when talking about the human experiments.) To adapt the experiment for cuttlefish, the researchers first figured out the cuttlefish's favorite food: live grass shrimp; and their second-favorite food: a piece of king prawn. Instead of choosing one or two marshmallows, the cuttlefish had to choose either their favorite food or second-favorite food. "Each of the food items were placed in clear chambers within their tank," Schnell says. "One chamber would open immediately, whereas the other chamber would only open after a delay." © 2021 npr

Keyword: Evolution; Learning & Memory
Link ID: 27724 - Posted: 03.11.2021

By Christa Lesté-Lasserre The famed stallion Black Beauty felt joy, excitement, and even heartbreak—or so he tells us in the 1877 novel that bears his name. Now, scientists say they’ve been able to detect feelings in living animals by getting them straight from the horse’s mouth—or in this case, its head. Researchers have devised a new, mobile headband that detects brain waves in horses, which could eventually be used with other species. “This is a real breakthrough,” says Katherine Houpt, a veterinary behaviorist at Cornell University who was not involved with the work. The device, she says, “gets into the animals’ minds” with objectivity and less guesswork. Ethologist Martine Hausberger had the idea while investigating whether stressed horses had a harder time learning to open a sliding door over a food box. (Spoiler alert: They do.) Hausberger, of the University of Rennes, noticed some of the animals—specifically, those living in cramped spaces—were paying less attention to the lessons. Were they depressed? An electroencephalogram (EEG) could theoretically pick up on such a mental state. Scientists have used the devices, which record waves of electrical impulses in the brain, since the early 1900s to study epilepsy and sleep patterns. More recently, they’ve discovered that certain EEG waves can signal depression, anxiety, and even contentedness in humans. EEG studies in rodents, farm animals, and pets, meanwhile, have revealed how they react to being touched by a human or undergoing anesthesia. But so far, no one had found a way to record brain waves in animals while they move around. © 2021 American Association for the Advancement of Science.

Keyword: Brain imaging
Link ID: 27723 - Posted: 03.11.2021

By Laura Sanders A century ago, science’s understanding of the brain was primitive, like astronomy before telescopes. Certain brain injuries were known to cause specific problems, like loss of speech or vision, but those findings offered a fuzzy view. Anatomists had identified nerve cells, or neurons, as key components of the brain and nervous system. But nobody knew how these cells collectively manage the brain’s sophisticated control of behavior, memory or emotions. And nobody knew how neurons communicate, or the intricacies of their connections. For that matter, the research field known as neuroscience — the science of the nervous system — did not exist, becoming known as such only in the 1960s. Over the last 100 years, brain scientists have built their telescopes. Powerful tools for peering inward have revealed cellular constellations. It’s likely that over 100 different kinds of brain cells communicate with dozens of distinct chemicals. A single neuron, scientists have discovered, can connect to tens of thousands of other cells. Yet neuroscience, though no longer in its infancy, is far from mature. Today, making sense of the brain’s vexing complexity is harder than ever. Advanced technologies and expanded computing capacity churn out torrents of information. “We have vastly more data … than we ever had before, period,” says Christof Koch, a neuroscientist at the Allen Institute in Seattle. Yet we still don’t have a satisfying explanation of how the brain operates. We may never understand brains in the way we understand rainbows, or black holes, or DNA. © Society for Science & the Public 2000–2021.

Keyword: Brain imaging; Learning & Memory
Link ID: 27722 - Posted: 03.06.2021

By Cathleen O’Grady People who take tiny amounts of LSD, “magic mushrooms,” and related drugs report a range of benefits, from more creativity to improved psychological well-being. But do these microdoses—typically less than 10% of the amount that causes a true psychedelic experience—actually benefit the mind? That’s been a hard question to answer. Placebo-controlled trials are tricky to pull off, because psychedelics are so tightly regulated. Now, researchers have come up with a creative workaround: They’ve enlisted microdosing enthusiasts to hide their drugs in gel capsules and mix them up with empty capsules. The upshot of this “self-blinding” study: Microdosing did lead to improvements in psychological well-being—but so did the placebo capsules. “The benefits are real,” says lead author Balázs Szigeti, a neuroscientist at Imperial College London. “But they are not caused by the pharmacological effects of microdosing.” The findings, however, are “the least interesting thing about this study,” says Noah Haber, a study design specialist at Stanford University. The “very, very clever” method of self-blinding pushes the boundaries of what can be investigated using randomized placebo controls, he says. Getting the new study off the ground wasn’t easy. Obtaining ethical approval to enroll psychedelic-taking volunteers was a “long and difficult process,” Szigeti says. And then he had to go out and find those volunteers, which he did by reaching out to microdosing communities, giving talks at psychedelic societies, and holding an “ask me anything” discussion on Reddit. Szigeti eventually garnered more than 1600 sign-ups, but once potential participants realized they’d have to procure their own psychedelics, interest ebbed, and only 246 ended up in the experiment. © 2021 American Association for the Advancement of Science.

Keyword: Depression; Drug Abuse
Link ID: 27721 - Posted: 03.06.2021

By Lisa Sanders, M.D. The voice on the phone was kind but firm: “You need to go to the emergency room. Now.” Her morning was going to be busy, replied the 68-year-old woman, and she didn’t feel well. Could she go later today or maybe tomorrow? No, said Dr. Benison Keung, her neurologist. She needed to go now; it was important. As she hung up the phone, tears blurred the woman’s already bad vision. She’d been worried for a while; now she was terrified. She was always healthy, until about four months earlier. It was a Saturday morning when she noticed that something seemed wrong with her right eye. She hurried to the bathroom mirror, where she saw that her right eyelid was drooping, covering the top half of the brown of her iris. On Monday morning, when she met her eye doctor, she was seeing double. Since then she’d had tests — so many tests — but received no answers. The woman walked to the bedroom where her 17-year-old granddaughter was still asleep. She woke her and asked for help getting dressed. Her hands were too weak for her to button her own clothes or tie her shoes. When she was completely dressed, she sent the girl to get her mother. She would need a ride to the hospital. She hadn’t been able to drive since she started seeing double. The events of the past few months had left the woman exhausted. First, she had seen her eye doctor. He took one look at her and told her that she had what’s called a third-nerve palsy. The muscles of the face and neck, he explained, are controlled by nerves that line up at the top of the spine. The nerve that controlled the eyelid, called the oculomotor nerve, was the third in this column. But he didn’t know what was affecting it or how to fix the problem. She needed to see a neuro-ophthalmologist, a doctor who specialized in the nerves that control the eyes. © 2021 The New York Times Company

Keyword: Movement Disorders; Neuroimmunology
Link ID: 27720 - Posted: 03.06.2021

By Erin Garcia de Jesus A whiff of catnip can make mosquitoes buzz off, and now researchers know why. The active component of catnip (Nepeta cataria) repels insects by triggering a chemical receptor that spurs sensations such as pain or itch, researchers report March 4 in Current Biology. The sensor, dubbed TRPA1, is common in animals — from flatworms to people — and responds to environmental irritants such as cold, heat, wasabi and tear gas. When irritants come into contact with TRPA1, the reaction can make people cough or an insect flee. Catnip’s repellent effect on insects — and its euphoric effect on felines — has been documented for millennia. Studies have shown that catnip may be as effective as the widely used synthetic repellent diethyl-m-toluamide, or DEET (SN: 9/5/01). But it was unknown how the plant repelled insects. So researchers exposed mosquitoes and fruit flies to catnip and monitored the insects’ behavior. Fruit flies were less likely to lay eggs on the side of a petri dish that was treated with catnip or its active component, nepetalactone. Mosquitoes were also less likely to take blood from a human hand coated with catnip. Insects that had been genetically modified to lack TRPA1, however, had no aversion to the plant. That behavior — coupled with experiments in lab-grown cells that show catnip activates TRPA1 — suggests that insect TRPA1 senses catnip as an irritant. Puzzling out how the plant deters insects could help researchers design potent repellents that may be easier to obtain in developing countries hit hard by mosquito-borne diseases. “Oil extracted from the plant or the plant itself could be a great starting point,” says study coauthor Marco Gallio, a neuroscientist at Northwestern University in Evanston, Ill. © Society for Science & the Public 2000–2021

Keyword: Pain & Touch; Evolution
Link ID: 27719 - Posted: 03.06.2021

By Veronique Greenwood Sign up for Science Times: Get stories that capture the wonders of nature, the cosmos and the human body. In the warm, fetid environs of a compost heap, tiny roundworms feast on bacteria. But some of these microbes produce toxins, and the worms avoid them. In the lab, scientists curious about how the roundworms can tell what’s dinner and what’s dangerous often put them on top of mats of various bacteria to see if they wriggle away. One microbe species, Pseudomonas aeruginosa, reliably sends them scurrying. But how do the worms, common lab animals of the species Caenorhabditis elegans, know to do this? Dipon Ghosh, then a graduate student in cellular and molecular physiology at Yale University, wondered if it was because they could sense the toxins produced by the bacteria. Or might it have something to do with the fact that mats of P. aeruginosa are a brilliant shade of blue? Given that roundworms do not have eyes, cells that obviously detect light or even any of the known genes for light-sensitive proteins, this seemed a bit far-fetched. It wasn’t difficult to set up an experiment to test the hypothesis, though: Dr. Ghosh, who is now a postdoctoral researcher at the Massachusetts Institute of Technology, put some worms on patches of P. aeruginosa. Then he turned the lights off. To the surprise of his adviser, Michael Nitabach, the worms’ flight from the bacteria was significantly slower in the dark, as though not being able to see kept the roundworms from realizing they were in danger. “When he showed me the results of the first experiments, I was shocked,” said Dr. Nitabach, who studies the molecular basis of neural circuits that guide behavior at Yale School of Medicine. In a series of follow-up experiments detailed in a paper published Thursday in Science, Dr. Ghosh, Dr. Nitabach and their colleagues establish that some roundworms respond clearly to that distinctive pigment, perceiving it — and fleeing from it — without the benefit of any known visual system. © 2021 The New York Times Company

Keyword: Vision; Evolution
Link ID: 27718 - Posted: 03.06.2021