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By Emily Anthes My cat is a bona fide chatterbox. Momo will meow when she is hungry and when she is full, when she wants to be picked up and when she wants to be put down, when I leave the room or when I enter it, or sometimes for what appears to be no real reason at all. But because she is a cat, she is also uncooperative. So the moment I downloaded MeowTalk Cat Translator, a mobile app that promised to convert Momo’s meows into plain English, she clammed right up. For two days I tried, and failed, to solicit a sound. On Day 3, out of desperation, I decided to pick her up while she was wolfing down her dinner, an interruption guaranteed to elicit a howl of protest. Right on cue, Momo wailed. The app processed the sound, then played an advertisement for Sara Lee, then rendered a translation: “I’m happy!” I was dubious. But MeowTalk provided a more plausible translation about a week later, when I returned from a four-day trip. Upon seeing me, Momo meowed and then purred. “Nice to see you,” the app translated. Then: “Let me rest.” (The ads disappeared after I upgraded to a premium account.) The urge to converse with animals is age-old, long predating the time when smartphones became our best friends. Scientists have taught sign language to great apes, chatted with grey parrots and even tried to teach English to bottlenose dolphins. Pets — with which we share our homes but not a common language — are particularly tempting targets. My TikTok feed brims with videos of Bunny, a sheepadoodle who has learned to press sound buttons that play prerecorded phrases like “outside,” “scritches” and “love you.” MeowTalk is the product of a growing interest in enlisting additional intelligences — machine-learning algorithms — to decode animal communication. The idea is not as far-fetched as it may seem. For example, machine-learning systems, which are able to extract patterns from large data sets, can distinguish between the squeaks that rodents make when they are happy and those that they emit when they are in distress. Applying the same advances to our creature companions has obvious appeal. “We’re trying to understand what cats are saying and give them a voice” Javier Sanchez, a founder of MeowTalk, said. “We want to use this to help people build better and stronger relationships with their cats,” he added. © 2022 The New York Times Company

Keyword: Animal Communication; Learning & Memory
Link ID: 28458 - Posted: 08.31.2022

Sofia Quaglia Dolphins form decade-long social bonds, and cooperate among and between cliques, to help one another find mates and fight off competitors, new research has found – behaviour not previously confirmed among animals. “These dolphins have long-term stable alliances, and they have intergroup alliances. Alliances of alliances of alliances, really,” said Dr Richard Connor, a behavioural ecologist at the University of Massachusetts Dartmouth and one of the lead authors of the paper. “But before our study, it had been thought that cooperative alliances between groups were unique to humans.” The findings, published on Monday in the journal Proceedings of the National Academy of Sciences, appear to support the “social brain” hypothesis: that mammals’ brains evolved to be larger in size for animals that keep track of their social interactions and networks. Humans and dolphins are the two animals with the largest brains relative to body size. “It’s not a coincidence,” Connor said. Connor’s team of researchers collected data between 2001 and 2006 by conducting intensive boat-based surveys in Shark Bay, Western Australia. The researchers tracked the dolphins by watching and listening to them, using their unique identifying whistles to tell them apart. They observed 202 Indo-Pacific bottlenose dolphins (Tursiops aduncus), including during the peak mating season between September and November. Back in the lab, they pored over data focusing on 121 of these adult male dolphins to observe patterns in their social networks. And for the next decade they continued to analyse the animals’ alliances. Dolphins’ social structures are fluid and complex. The researchers found alliances among two or three male dolphins – like best friends. Then the groups expanded to up to 14 members. Together, they helped each other find females to herd and mate with, and they help steal females from other dolphins as well as defend against any “theft” attempts from rivals. © 2022 Guardian News & Media Limited

Keyword: Sexual Behavior; Evolution
Link ID: 28457 - Posted: 08.31.2022

By Carl Zimmer One of the most remarkable things about our species is how fast human culture can change. New words can spread from continent to continent, while technologies such as cellphones and drones change the way people live around the world. It turns out that humpback whales have their own long-range, high-speed cultural evolution, and they don’t need the internet or satellites to keep it running. In a study published on Tuesday, scientists found that humpback songs easily spread from one population to another across the Pacific Ocean. It can take just a couple of years for a song to move several thousand miles. Ellen Garland, a marine biologist at the University of St. Andrews in Scotland and an author of the study, said she was shocked to find whales in Australia passing their songs to others in French Polynesia, which in turn gave songs to whales in Ecuador. “Half the globe is now vocally connected for whales,” she said. “And that’s insane.” It’s even possible that the songs travel around the entire Southern Hemisphere. Preliminary studies by other scientists are revealing whales in the Atlantic Ocean picking up songs from whales the eastern Pacific. Each population of humpback whales spends the winter in the same breeding grounds. The males there sing loud underwater songs that can last up to half an hour. Males in the same breeding ground sing a nearly identical tune. And from one year to the next, the population’s song gradually evolves into a new melody. Dr. Garland and other researchers have uncovered a complex, language-like structure in these songs. The whales combine short sounds, which scientists call units, into phrases. They then combine the phrases into themes. And each song is made of several themes. © 2022 The New York Times Company

Keyword: Animal Communication; Language
Link ID: 28456 - Posted: 08.31.2022

Researchers have published two papers describing how they identified a potential new pathway for treating a sporadic form of amyotrophic lateral sclerosis (ALS). The studies were published as part of a cooperative research agreement between the National Institute of Neurological Disorders and Stroke (NINDS), part of the National Institutes of Health, and the Switzerland-based biotechnology company GeNeuro Inc. One unusual side effect of hundreds of thousands of years of evolution is that the human genome now contains DNA sequences from ancient retroviruses—referred to as human endogenous retroviruses (HERVs). Though most remain dormant, reactivation of HERVs have been implicated in several neurodegenerative diseases, including ALS. The first of these papers shows that a specific HERV produces a protein that can be found in the cerebrospinal fluid (CSF) of people with ALS. This protein, called HERV-K ENV, is toxic when added to neurons grown in laboratory dishes. In addition, a special kind of mouse genetically designed to create HERV-K ENV develops symptoms very similar to ALS. Adding the CSF from people with ALS to lab-grown neurons resulted in damage to the cells. When a synthetic antibody designed specifically to recognize HERV-K ENV was added as well to those neurons, the toxic effects were reduced. These findings together suggest that the improper activation of the HERV-K ENV gene could be the cause of the symptoms seen in certain cases of sporadic ALS. The discovery that a synthetic antibody to HERV-K ENV could be protective led the researchers to look at whether the immune system of people with ALS produced any antibodies, as well. In the second paper, the authors show that indeed higher levels of antibodies against HERV-K ENV were seen in the blood of a group of people with ALS as compared to healthy donors. The pattern of antibodies against this viral protein was also more complex in persons with ALS. In addition, there was also a correlation between higher antibody levels against HERV-K ENV and longer overall survival.

Keyword: ALS-Lou Gehrig's Disease
Link ID: 28455 - Posted: 08.31.2022

Steven Strogatz Dreams are so personal, subjective and fleeting, they might seem impossible to study directly and with scientific objectivity. But in recent decades, laboratories around the world have developed sophisticated techniques for getting into the minds of people while they are dreaming. In the process, they are learning more about why we need these strange nightly experiences and how our brains generate them. In this episode, Steven Strogatz speaks with sleep researcher Antonio Zadra of the University of Montreal about how new experimental methods have changed our understanding of dreams. Steven Strogatz (00:03): I’m Steve Strogatz, and this is The Joy of Why, a podcast from Quanta Magazine that takes you into some of the biggest unanswered questions in math and science today. (00:13) In this episode, we’re going to be talking about dreams. What are dreams exactly? What purpose do they serve? And why are they often so bizarre? We’ve all had this experience: You’re dreaming about something fantastical, some kind of crazy story with a narrative arc that didn’t actually happen, with people we don’t necessarily know, in places we may have never even been. Is this just the brain trying to make sense of random neural firing? Or is there some evolutionary reason for dreaming? Dreams are inherently hard to study. Even with all the advances in science and technology, we still haven’t really found a way to record what someone else is dreaming about. Plus, as we all know, it’s easy to forget our dreams as soon as we wake up, unless we’re really careful to write them down. But even with all these difficulties, little by little, dream researchers are making progress in figuring out how we dream and why we dream. (01:11) Joining me now to discuss all this is Dr. Antonio Zadra, a professor at the University of Montreal and a researcher at the Center for Advanced Research in Sleep Medicine. His specialties include the study of nightmares, recurrent dreams and lucid dreaming. He’s also the coauthor of the recent book When Brains Dream, exploring the science and mystery of sleep. Tony, thank you so much for joining us today. Strogatz (01:39): I’m very excited to talk to you about this. So let’s start with thinking about the science of dreams as you and your colleagues see it today. Why are dreams so hard to study? All Rights Reserved © 2022

Keyword: Sleep; Evolution
Link ID: 28454 - Posted: 08.27.2022

Yuta Senzai Massimo Scanziani Does rapid eye movement during sleep reveal where you’re looking at in the scenery of dreams, or are they simply the result of random jerks of our eye muscles? Since the discovery of REM sleep in the early 1950s, the significance of these rapid eye movements has intrigued and fascinated scores of scientists, psychologists and philosophers. REM sleep, as the name implies, is a period of sleep when your eyes move under your closed eyelids. It’s also the period when you experience vivid dreams. We are researchers who study how the brain processes sensory information during wakefulness and sleep. In our recently published study, we found that the eye movements you make while you sleep may reflect where you’re looking in your dreams. Past studies have attempted to address this question by monitoring the eye movements of people as they slept and waking them up to ask what they were dreaming. The goal was to find a possible connection between the content of a dream just before waking up (say, a car coming in from the left) and the direction the eyes moved at that moment. Unfortunately, these studies have led to contradictory results. It could be that some participants inaccurately reported dreams, and it’s technically difficult to match a given eye movement to a specific moment in a self-reported dream. We decided to bypass the problem of dream self-reporting. Instead, we used a more objective way to measure dreams: the electrical activity of a sleeping mouse brain. Mice, like humans and many other animals, also experience REM sleep. Additionally, they have a sort of internal compass in their brains that gives them a sense of head direction. When the mouse is awake and running around, the electrical activity of this internal compass precisely reports its head direction, or “heading,” as it moves in its environment. © 2010–2022, The Conversation US, Inc.

Keyword: Sleep; Vision
Link ID: 28453 - Posted: 08.27.2022

Sascha Pare Homer Simpson may not be the only one with a region of the brain dedicated to doughnuts: researchers have found that images of food appear to trigger a specific set of neurons. Previous research found that similar regions of the brain are highly specialised to identify and remember faces, places, bodies and words. The team, based at the Massachusetts Institute of Technology (MIT), say they stumbled upon the food-sensitive neurons by accident – and they could have evolved due to the evolutionary and cultural importance of food for humans. “Our most novel result is the discovery of a new neural response that has not been reported previously for the ventral visual pathway and that is highly selective for images of food,” the scientists wrote in the journal Current Biology. The researchers examined brain scans of eight participants taken as they viewed 10,000 images. Pictures of food appeared to trigger a population of neurons in the ventral visual cortex, which processes visual information. “We were quite puzzled by this because food is not a visually homogenous category,” said Meenakshi Khosla, one of the lead authors of the study. “Things like apples and corn and pasta all look so unlike each other, yet we found a single population that responds similarly to all these diverse food items.” Cooked meals such as a cheesy slice of pizza provoked a slightly stronger reactions than raw fruit and vegetables, the researchers noted. To test whether this was due to warmer colours in prepared food, they compared participants’ reactions with cool-toned images of food and richly coloured non-food objects. They found food caused a sharper signal. © 2022 Guardian News & Media Limited

Keyword: Obesity; Brain imaging
Link ID: 28452 - Posted: 08.27.2022

By Anil Oza Sitting alone in the cockpit of a small biplane, Martin Wikelski listens for the pings of a machine by his side. The sonic beacons help the ecologist stalk death’s-head hawkmoths (Acherontia atropos) fluttering across the dark skies above Konstanz, Germany — about 80 kilometers north of the Swiss Alps. The moths, nicknamed for the skull-and-crossbones pattern on their backs, migrate thousands of kilometers between northern Africa and the Alps during the spring and fall. Many migratory insects go where the wind takes them, says Ring Carde, an entomologist at the University of California, Riverside who is not a member of Wikelski’s team. Death’s-head hawkmoths appear to be anything but typical. “When I follow them with a plane, I use very little gas,” says Wikelski, of the Max Planck Institute of Animal Behavior in Munich. “That shows me that they are supposedly choosing directions or areas that are probably supported by a little bit of updraft.” A new analysis of data collected from 14 death’s-head hawkmoths suggest that these insects indeed pilot themselves, possibly relying in part on an internal compass attuned to Earth’s magnetic field. The moths not only fly along a straight path, they also stay the course even when winds change, Wikelski and colleagues report August 11 in Science. The findings could help predict how the moths’ flight paths might shift as the globe continues warming, Wikelski says. Like many animals, death’s-head hawkmoths will probably move north in search of cooler temperatures, he suspects. To keep tabs on the moths, Wikelski’s team glued radio transmitters to their backs, which is easier to do than one might expect. “Death’s-head hawkmoths are totally cool,” Wikelski says. They’re also huge. Weighing as much as three jellybeans, the moths are the largest in Europe. That makes attaching the tiny tags a cinch, though the moths don’t like it very much. “They talk to you, they shout at you a little bit,” he says. © Society for Science & the Public 2000–2022.

Keyword: Animal Migration
Link ID: 28451 - Posted: 08.27.2022

By Matt Richtel This article examines the increase in anxiety, depression, self harm and suicide among U.S. adolescents. Parents and teenagers dealing with these issues can find resources here. One morning in the fall of 2017, Renae Smith, a high school freshman on Long Island, N.Y., could not get out of bed, overwhelmed at the prospect of going to school. In the following days, her anxiety mounted into despair. “I should have been happy,” she later wrote. “But I cried, screamed and begged the universe or whatever godly power to take away the pain of a thousand men that was trapped inside my head.” Intervention for her depression and anxiety came not from the divine but from the pharmaceutical industry. The following spring, a psychiatrist prescribed Prozac. The medication offered a reprieve from her suffering, but the effect dissipated, so she was prescribed an additional antidepressant, Effexor. A medication cascade had begun. During 2021, the year she graduated, she was prescribed seven drugs. These included one for seizures and migraines — she experienced neither, but the drug can be also used to stabilize mood — and another to dull the side effects of the other medications, although it is used mainly for schizophrenia. She felt better some days but deeply sad on others. Her senior yearbook photo shows her smiling broadly, “but I felt terrible that day,” said Ms. Smith, who is now 19 and attends a local community college. “I’ve gotten good at wearing a mask.” She had come to exemplify a medical practice common among her generation: the simultaneous use of multiple heavy-duty psychiatric drugs. Psychiatrists and other clinicians emphasize that psychiatric drugs, properly prescribed, can be vital in stabilizing adolescents and saving the lives of suicidal teens. But, these experts caution, such medications are too readily doled out, often as an easy alternative to therapy that families cannot afford or find, or aren’t interested in. © 2022 The New York Times Company

Keyword: Drug Abuse; Depression
Link ID: 28450 - Posted: 08.27.2022

By Kurt Kleiner The human brain is an amazing computing machine. Weighing only three pounds or so, it can process information a thousand times faster than the fastest supercomputer, store a thousand times more information than a powerful laptop, and do it all using no more energy than a 20-watt lightbulb. Researchers are trying to replicate this success using soft, flexible organic materials that can operate like biological neurons and someday might even be able to interconnect with them. Eventually, soft “neuromorphic” computer chips could be implanted directly into the brain, allowing people to control an artificial arm or a computer monitor simply by thinking about it. Like real neurons — but unlike conventional computer chips — these new devices can send and receive both chemical and electrical signals. “Your brain works with chemicals, with neurotransmitters like dopamine and serotonin. Our materials are able to interact electrochemically with them,” says Alberto Salleo, a materials scientist at Stanford University who wrote about the potential for organic neuromorphic devices in the 2021 Annual Review of Materials Research. Salleo and other researchers have created electronic devices using these soft organic materials that can act like transistors (which amplify and switch electrical signals) and memory cells (which store information) and other basic electronic components. The work grows out of an increasing interest in neuromorphic computer circuits that mimic how human neural connections, or synapses, work. These circuits, whether made of silicon, metal or organic materials, work less like those in digital computers and more like the networks of neurons in the human brain. © 2022 Annual Reviews

Keyword: Robotics; Learning & Memory
Link ID: 28449 - Posted: 08.27.2022

By Andrew Jacobs A small study on the therapeutic effects of using psychedelics to treat alcohol use disorder found that just two doses of psilocybin magic mushrooms paired with psychotherapy led to an 83 percent decline in heavy drinking among the participants. Those given a placebo reduced their alcohol intake by 51 percent. By the end of the eight-month trial, nearly half of those who received psilocybin had stopped drinking entirely compared with about a quarter of those given the placebo, according to the researchers. The study, published Wednesday in JAMA Psychiatry, is the latest in a cascade of new research exploring the benefits of mind-altering compounds to treat a range of mental health problems, from depression, anxiety and post-traumatic stress disorder to the existential dread experienced by the terminally ill. Although most psychedelics remain illegal under federal law, the Food and Drug Administration is weighing potential therapeutic uses for compounds like psilocybin, LSD and MDMA, the drug better known as Ecstasy. Dr. Michael Bogenschutz, director at NYU Langone Center for Psychedelic Medicine and the study’s lead investigator, said the findings offered hope for the nearly 15 million Americans who struggle with excessive drinking — roughly 5 percent of all adults. Excessive alcohol use kills an estimated 140,000 people each year. “These are exciting results,” Dr. Bogenschutz said. “Alcohol use disorder is a serious public health problem, and the effects of currently available treatments and medications tend to be small.” The double-blind randomized trial followed 93 participants for 32 weeks and divided them into two groups: One received psilocybin and the other a placebo in the form of antihistamine pills. The participants, all of whom struggled with excessive drinking, also took part in 12 therapy sessions that began several weeks before they received their first doses and continued for a month after the final dose. The psilocybin dosage was determined according to participants’ weight, and their heart rate and blood pressure were monitored during the eight-hour sessions. © 2022 The New York Times Company

Keyword: Drug Abuse; Depression
Link ID: 28448 - Posted: 08.27.2022

By Betsy Mason 08.05.2022 What is special about humans that sets us apart from other animals? Less than some of us would like to believe. As scientists peer more deeply into the lives of other animals, they’re finding that our fellow creatures are far more emotionally, socially, and cognitively complex than we typically give them credit for. A deluge of innovative research is revealing that behavior we would call intelligent if humans did it can be found in virtually every corner of the animal kingdom. Already this year scientists have shown that Goffin’s cockatoos can use multiple tools at once to solve a problem, Australian Magpies will cooperate to remove tracking devices harnessed to them by scientists, and a small brown songbird can sometimes keep time better than the average professional musician — and that’s just among birds. This pileup of fascinating findings may be at least partly responsible for an increase in people’s interest in the lives of other animals — a trend that’s reflected in an apparent uptick in books and television shows on the topic, as well as in legislation concerning other species. Public sentiment in part pushed the National Institutes of Health to stop supporting biomedical research on chimpanzees in 2015. In Canada, an outcry led to a ban in 2019 on keeping cetaceans like dolphins and orcas in captivity. And earlier this year, the United Kingdom passed an animal welfare bill that officially recognizes that many animals are sentient beings capable of suffering, including invertebrates like octopuses and lobsters. Many of these efforts are motivated by human empathy for animals we’ve come to see as intelligent, feeling beings like us, such as chimpanzees and dolphins. But how can we extend that concern to the millions of other species that share the planet with us?

Keyword: Vision; Hearing
Link ID: 28447 - Posted: 08.27.2022

By Fionna M. D. Samuels, Liz Tormes Experiencing art, whether through melody or oil paint, elicits in us a range of emotions. This speaks to the innate entanglement of art and the brain: Mirror neurons can make people feel like they are physically experiencing a painting. And listening to music can change their brain chemistry. For the past 11 years, the Netherlands Institute for Neuroscience in Amsterdam has hosted the annual Art of Neuroscience Competition and explored this intersection. This year’s competition received more than 100 submissions, some created by artists inspired by neuroscience and others by neuroscientists inspired by art. The top picks explore a breadth of ideas—from the experience of losing consciousness to the importance of animal models in research—but all of them tie back to our uniquely human brain. In the moment between wakefulness and sleep, we may feel like we are losing ourself to the void of unconsciousness. This is the moment Daniela de Paulis explores with her interdisciplinary project Mare Incognito. “I always had a fascination for the moment of falling asleep,” she says. “Since I was a very small child, I always found this moment as quite transformative, also quite frightening in a way.” The winning Art of Neuroscience submission is the culmination of her project: a film that recorded de Paulis falling asleep among the silver, treelike antennas of the Square Kilometer Array at the Mullard Radio Observatory in Cambridge, England, while her brain activity was converted into radio waves and transmitted directly into space. “We combined the scientific interest with my poetic fascination in this idea of losing consciousness,” she says. In the clip above, Tristan Bekinschtein, a neuroscientist at the University of Cambridge, explains the massive change humans and their brain experience when they drift from consciousness into sleep. As someone falls asleep, their brain activity slows down in stages until they are fully out. Then bursts of activity light up their gray matter as their brain switches over to rapid eye movement (REM) sleep, and they begin to dream. © 2022 Scientific American,

Keyword: Vision; Brain imaging
Link ID: 28446 - Posted: 08.27.2022

Diana Kwon People’s ability to remember fades with age — but one day, researchers might be able to use a simple, drug-free method to buck this trend. In a study published on 22 August in Nature Neuroscience1, Robert Reinhart, a cognitive neuroscientist at Boston University in Massachusetts, and his colleagues demonstrate that zapping the brains of adults aged over 65 with weak electrical currents repeatedly over several days led to memory improvements that persisted for up to a month. Previous studies have suggested that long-term memory and ‘working’ memory, which allows the brain to store information temporarily, are controlled by distinct mechanisms and parts of the brain. Drawing on this research, the team showed that stimulating the dorsolateral prefrontal cortex — a region near the front of the brain — with high-frequency electrical currents improved long-term memory, whereas stimulating the inferior parietal lobe, which is further back in the brain, with low-frequency electrical currents boosted working memory. “Their results look very promising,” says Ines Violante, a neuroscientist at the University of Surrey in Guildford, UK. “They really took advantage of the cumulative knowledge within the field.” Using a non-invasive method of stimulating the brain known as transcranial alternating current stimulation (tACS), which delivers electrical currents through electrodes on the surface of the scalp, Reinhart’s team conducted a series of experiments on 150 people aged between 65 and 88. Participants carried out a memory task in which they were asked to recall lists of 20 words that were read aloud by an experimenter. The participants underwent tACS for the entire duration of the task, which took 20 minutes. © 2022 Springer Nature Limited

Keyword: Learning & Memory
Link ID: 28445 - Posted: 08.24.2022

By Sujata Gupta Lack of sleep has been linked to heart disease, poor mood and loneliness (SN: 11/15/16). Being tired could also make us less generous, researchers report August 23 in PLOS Biology. The hour of sleep lost in the switch over to Daylight Savings Time every spring appears to reduce people’s tendency to help others, the researchers found in one of three experiments testing the link between sleep loss and generosity. Specifically, they showed that average donations to one U.S.-based nonprofit organization dropped by around 10 percent in the workweek after the time switch compared with four weeks before and after the change. In Arizona and Hawaii, states that do not observe Daylight Savings Time, donations remained unchanged. With over half of the people living in parts of the developed world reporting that they rarely get enough sleep during the workweek, the finding has implications beyond the week we spring forward, the researchers say. “Lack of sleep shapes the social experiences we have [and] the kinds of societies we live in,” says neuroscientist Eti Ben Simon of the University of California, Berkeley. To test the link between sleep loss and generosity, Ben Simon and her team first brought 23 young adults into the lab for two nights. The participants slept through one night and stayed awake for another night. In the mornings, participants completed a standardized altruism questionnaire rating their likelihood of helping strangers or acquaintances in various scenarios. For instance, participants rated on a scale from 1 to 5, with 1 for least likely to help and 5 for most likely, whether they would give up their seat on a bus to a stranger or offer a ride to a coworker in need. Participants never read the same scenario more than once. Roughly 80 percent of participants showed less likelihood of helping others when sleep-deprived than when rested. © Society for Science & the Public 2000–2022.

Keyword: Sleep; Emotions
Link ID: 28444 - Posted: 08.24.2022

By Andrew Jacobs Marijuana and hallucinogen use among young adults reached an all-time record last year after having leveled off during the first year of the coronavirus pandemic, according to federal survey data. The findings, part of the government’s annual survey of drug use among young Americans, also found that nicotine vaping and excessive alcohol consumption continued to climb in 2021 after a brief pause. Another worrying trend among young people, ages 19 to 30: mounting consumption of alcoholic beverages suffused with THC, the psychoactive ingredient in cannabis. But there were some bright spots in the survey. Cigarette smoking and opioid abuse among young adults dropped last year, a continuing trend that has heartened public health experts. Taken in its entirety, the report provides a mixed picture of substance use in the United States that experts say reflects a number of disparate trends affecting young Americans: the devastating mental health effects of the pandemic; the increased availability of legal marijuana; and the emerging therapeutic embrace of psychedelics to treat depression, post-traumatic stress disorder and other psychological problems. “Overall, the results are very concerning,” said Dr. Nora Volkow, director of the National Institute on Drug Abuse, which publishes the annual Monitoring the Future survey. “What they tell us is that the problem of substance abuse among young people has gotten worse in this country, and that the pandemic, with all its mental stressors and turmoil, has likely contributed to the rise.” The online survey of people ages 19 to 60 was conducted from April to October 2021. Substance use research experts said the mounting use of marijuana in young adults was especially notable. The survey found that 43 percent in the 19-30 age group had used cannabis 20 or more times over the previous month, up from 34 percent. In 2011, that figure was 29 percent. Daily marijuana consumption also jumped significantly, to 11 percent from 6 percent in 2011. © 2022 The New York Times Company

Keyword: Drug Abuse
Link ID: 28443 - Posted: 08.24.2022

By Diana Kwon During an embryo's development, a piece of the still-growing brain branches off to form the retina, a sliver of tissue in the back of the eye. This makes the retina, which is composed of several layers of neurons, a piece of the central nervous system. As evidence builds that changes in the brain can manifest in this region, scientists are turning to retinas as a potential screening target for early signs of Alzheimer's, an incurable neurodegenerative disease that affects an estimated six million people in the U.S. alone. Initially clinicians could diagnose Alzheimer's only through brain autopsies after patients died. Since the early 2000s, however, research advances have made it possible to pinpoint signs of the disease—and to begin to investigate treatment—years before symptoms first appear. Today positron emission tomography (PET) brain imaging and tests of cerebrospinal fluid (CSF), the clear liquid surrounding the brain and spinal cord, aid Alzheimer's diagnosis at its early stages. “There have been tremendous improvements in our ability to detect early disease,” says Peter J. Snyder, a neuropsychologist and neuroscientist at the University of Rhode Island. But these diagnostic methods are not always readily available, and they can be expensive and invasive. PET imaging requires injecting a radioactive tracer molecule into the bloodstream, and spinal fluid must be extracted with a needle inserted between vertebrae in the back. “We need ways of funneling the right high-risk individuals into the diagnostic process with low-cost screening tools that are noninvasive and simple to administer,” Snyder says. The retina is a particularly attractive target, he adds, because it is closely related to brain tissue and can be examined noninvasively through the pupil, including with methods routinely used to check for eye diseases. © 2022 Scientific American,

Keyword: Alzheimers; Vision
Link ID: 28442 - Posted: 08.24.2022

Jason Bruck Bottlenose dolphins’ signature whistles just passed an important test in animal psychology. A new study by my colleagues and me has shown that these animals may use their whistles as namelike concepts. By presenting urine and the sounds of signature whistles to dolphins, my colleagues Vincent Janik, Sam Walmsey and I recently showed that these whistles act as representations of the individuals who own them, similar to human names. For behavioral biologists like us, this is an incredibly exciting result. It is the first time this type of representational naming has been found in any other animal aside from humans. When you hear your friend’s name, you probably picture their face. Likewise, when you smell a friend’s perfume, that can also elicit an image of the friend. This is because humans build mental pictures of each other using more than just one sense. All of the different information from your senses that is associated with a person converges to form a mental representation of that individual - a name with a face, a smell and many other sensory characteristics. Within the first few months of life, dolphins invent their own specific identity calls – called signature whistles. Dolphins often announce their location to or greet other individuals in a pod by sending out their own signature whistles. But researchers have not known if, when a dolphin hears the signature whistle of a dolphin they are familiar with, they actively picture the calling individual. My colleagues and I were interested in determining if dolphin calls are representational in the same way human names invoke many thoughts of an individual. Because dolphins cannot smell, they rely principally on signature whistles to identify each other in the ocean. Dolphins can also copy another dolphin’s whistles as a way to address each other. My previous research showed that dolphins have great memory for each other’s whistles, but scientists argued that a dolphin might hear a whistle, know it sounds familiar, but not remember who the whistle belongs to. My colleagues and I wanted to determine if dolphins could associate signature whistles with the specific owner of that whistle. This would address whether or not dolphins remember and hold representations of other dolphins in their minds. © 2010–2022, The Conversation US, Inc.

Keyword: Language; Evolution
Link ID: 28441 - Posted: 08.24.2022

By Kate Golembiewski Humans spend about 35 minutes every day chewing. That adds up to more than a full week out of every year. But that’s nothing compared to the time spent masticating by our cousins: Chimps chew for 4.5 hours a day, and orangutans clock 6.6 hours. The differences between our chewing habits and those of our closest relatives offer insights into human evolution. A study published Wednesday in the journal Science Advances explores how much energy people use while chewing, and how that may have guided — or been guided by — our gradual transformation into modern humans. Chewing, in addition to keeping us from choking, makes the energy and nutrients in food accessible to the digestive system. But the very act of chewing requires us to expend energy. Adaptations to teeth, jaws and muscles all play a part in how efficiently humans chew. Adam van Casteren, an author of the new study and a research associate at the University of Manchester in England, says that scientists haven’t delved too deeply into the energetic costs of chewing partly because compared with other things we do, such as walking or running, it’s a thin slice of the energy-use pie. But even comparatively small advantages can play a big role in evolution, and he wanted to find out if that might be the case with chewing. To measure the energy that goes into chewing, Dr. van Casteren and his colleagues outfitted study participants in the Netherlands with plastic hoods that look like “an astronaut’s helmet,” he said. The hoods were connected to tubes to measure oxygen and carbon dioxide from breathing. Because metabolic processes are fueled by oxygen and produce carbon dioxide, gas exchange can be a useful measure for how much energy something takes. The researchers then gave the subjects gum. The participants didn’t get the sugary kind, though; the gum bases they chewed were flavorless and odorless. Digestive systems respond to flavors and scents, so the researchers wanted to make sure they were only measuring the energy associated with chewing and not the energy of a stomach gearing up for a tasty meal. The test subjects chewed two pieces of gum, one hard and one soft, for 15 minutes each. The results surprised researchers. The softer gum raised the participants’ metabolic rates about 10 percent higher than when they were resting; the harder gum caused a 15 percent increase. © 2022 The New York Times Company

Keyword: Evolution
Link ID: 28440 - Posted: 08.20.2022

By Erin Garcia de Jesús Some mosquitoes have a near-foolproof thirst for human blood. Previous attempts to prevent the insects from tracking people down by blocking part of mosquitoes’ ability to smell have failed. A new study hints it’s because the bloodsuckers have built-in workarounds to ensure they can always smell us. For most animals, individual nerve cells in the olfactory system can detect just one type of odor. But Aedes aegypti mosquitoes’ nerve cells can each detect many smells, researchers report August 18 in Cell. That means if a cell were to lose the ability to detect one human odor, it still can pick up on other scents. The study provides the most detailed map yet of a mosquito’s sense of smell and suggests that concealing human aromas from the insects could be more complicated than researchers thought. Repellents that block mosquitoes from detecting human-associated scents could be especially tricky to make. “Maybe instead of trying to mask them from finding us, it would be better to find odorants that mosquitoes don’t like to smell,” says Anandasankar Ray, a neuroscientist at the University of California, Riverside who was not involved in the work. Such repellents may confuse or irritate the bloodsuckers and send them flying away (SN: 9/21/11; SN: 3/4/21). Effective repellents are a key tool to prevent mosquitoes from transmitting disease-causing viruses such as dengue and Zika (SN: 7/11/22). “Mosquitoes are responsible for more human deaths than any other creature,” says Olivia Goldman, a neurobiologist at Rockefeller University in New York City. “The better we understand them, the better that we can have these interventions.” © Society for Science & the Public 2000–2022.

Keyword: Chemical Senses (Smell & Taste); Evolution
Link ID: 28439 - Posted: 08.20.2022