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By Joanna Thompson People often think they know what causes chronic depression. Surveys indicate that more than 80% of the public blames a “chemical imbalance” in the brain. That idea is widespread in pop psychology and cited in research papers and medical textbooks. Listening to Prozac, a book that describes the life-changing value of treating depression with medications that aim to correct this imbalance, spent months on the New York Times bestseller list. The unbalanced brain chemical in question is serotonin, an important neurotransmitter with fabled “feel-good” effects. Serotonin helps regulate systems in the brain that control everything from body temperature and sleep to sex drive and hunger. For decades, it has also been touted as the pharmaceutical MVP for fighting depression. Widely prescribed medications like Prozac (fluoxetine) are designed to treat chronic depression by raising serotonin levels. Yet the causes of depression go far beyond serotonin deficiency. Clinical studies have repeatedly concluded that the role of serotonin in depression has been overstated. Indeed, the entire premise of the chemical-imbalance theory may be wrong, despite the relief that Prozac seems to bring to many patients. If you were still of the opinion that it was simply a chemical imbalance of serotonin, then yeah, it’s pretty damning. A literature review that appeared in Molecular Psychiatry in July was the latest and perhaps loudest death knell for the serotonin hypothesis, at least in its simplest form. An international team of scientists led by Joanna Moncrieff of University College London screened 361 papers from six areas of research and carefully evaluated 17 of them. They found no convincing evidence that lower levels of serotonin caused or were even associated with depression. People with depression didn’t reliably seem to have less serotonin activity than people without the disorder. Experiments in which researchers artificially lowered the serotonin levels of volunteers didn’t consistently cause depression. Genetic studies also seemed to rule out any connection between genes affecting serotonin levels and depression, even when the researchers tried to consider stress as a possible cofactor. All Rights Reserved © 2023

Keyword: Depression; Stress
Link ID: 28647 - Posted: 01.27.2023

By Dana G. Smith Do you: Cut the tags out of your clothes? Relive (and regret) past conversations? Have episodes of burnout and fatigue? Zone out while someone is talking? Become hyper-focused while working on a project? Take on dozens of hobbies? Daydream? Forget things? According to TikTok, you might have attention deficit hyperactivity disorder. Videos about the psychiatric condition are all over the social media app, with the #adhd hashtag receiving more than 17 billion views to date. Many feature young people describing their specific (and sometimes surprising) symptoms, like sensitivity to small sensory annoyances (such as clothing tags) or A.D.H.D. paralysis, a type of extreme procrastination. After viewing these videos, many people who were not diagnosed with A.D.H.D. as children may question whether they would qualify as adults. As with most psychiatric conditions, A.D.H.D. symptoms can range in type and severity. And many of them “are behaviors everyone experiences at some point or another,” said Joel Nigg, a professor of psychiatry at Oregon Health & Science University. The key to diagnosing the condition, however, requires “determining that it’s serious, it’s extreme” and it’s interfering with people’s lives, he said. It’s also critical that the symptoms have been present since childhood. Those nuances can be lost on social media, experts say. In fact, one study published earlier this year found that more than half of the A.D.H.D. videos on TikTok were misleading. If a video (or article) has you thinking you may have undiagnosed A.D.H.D., here’s what to consider. Approximately 4 percent of adults in the United States have enough symptoms to qualify for A.D.H.D., but only an estimated one in 10 of them is diagnosed and treated. For comparison, roughly 9 percent of children in the United States have been diagnosed with the condition, and three-quarters have received medication or behavioral therapy for it. One reason for the lack of diagnoses in adults is that when people think of A.D.H.D., they often imagine a boy who can’t sit still and is disruptive in class, said Dr. Deepti Anbarasan, a clinical associate professor of psychiatry at the NYU Grossman School of Medicine. But those stereotypical hyperactive symptoms are present in just 5 percent of adult cases, she said. © 2023 The New York Times Company

Keyword: ADHD
Link ID: 28646 - Posted: 01.27.2023

Liam Drew The emergence of disease-causing bacteria that are resistant to antibiotics is often attributed to the overuse of antibiotics in people and livestock. But researchers have homed in on another potential driver of resistance: antidepressants. By studying bacteria grown in the laboratory, a team has now tracked how antidepressants can trigger drug resistance1. “Even after a few days exposure, bacteria develop drug resistance, not only against one but multiple antibiotics,” says senior author Jianhua Guo, who works at the Australian Centre for Water and Environmental Biotechnology at the University of Queensland in Brisbane. This is both interesting and scary, he says. Globally, antibiotic resistance is a significant public-health threat. An estimated 1.2 million people died as a direct result of it in 20192, and that number is predicted to climb. Early clues Guo became interested in the possible contributions of non-antibiotic drugs to antibiotic resistance in 2014, after work by his lab found more antibiotic-resistance genes circulating in domestic wastewater samples than in samples of wastewater from hospitals, where antibiotic use is higher. Guo’s group and other teams also observed that antidepressants — which are among the most widely prescribed medicines in the world — killed or stunted the growth of certain bacteria. They provoke “an SOS response”, Guo explains, triggering cellular defence mechanisms that, in turn, make the bacteria better able to survive subsequent antibiotic treatment. © 2023 Springer Nature Limited

Keyword: Depression
Link ID: 28645 - Posted: 01.27.2023

By Annabelle Timsit A new study of more than 29,000 older adults has identified six habits — from eating a variety of foods to regularly reading or playing cards — that are linked with a lower risk of dementia and a slower rate of memory decline. Eating a balanced diet, exercising the mind and body regularly, having regular contact with others, and not drinking or smoking — these six “healthy lifestyle factors” were associated with better cognitive outcomes in older adults, in a large Chinese study conducted over a decade and published in the BMJ on Wednesday. While researchers have long known that there is a link between dementia and factors such as social isolation and obesity, the size and scope of the new study adds substantial evidence to a global body of research that suggests a healthy lifestyle may help brains age better. It also suggests that the effects of a healthy lifestyle are beneficial even for people who are genetically more susceptible to memory decline — a “very hope-giving” finding for the millions of individuals around the world who carry the APOEε4 gene, a major risk factor for Alzheimer’s disease, said Eef Hogervorst, chair of biological psychology at Loughborough University, who was not involved in the study. Memory naturally declines gradually as people age. Some older people may develop dementia, an umbrella term that can include Alzheimer’s, and generally describes a deterioration in cognitive function that goes beyond the normal effects of aging. But for many, “memory loss can merely be senescent forgetfulness,” write the authors of the BMJ study — like forgetting the name of that TV program you used to love, or that pesky fact you wanted to look up. Memory loss is no less damaging for being gradual, and age-related memory decline can in some cases be an early symptom of dementia. But the good news, the researchers say, is that it “can be reversed or become stable rather than progress to a pathological state.” How do you live to be 100? Good genes, getting outside and friends.

Keyword: Alzheimers
Link ID: 28644 - Posted: 01.27.2023

By Jennifer Szalai “‘R’s’ are hard,” John Hendrickson writes in his new memoir, “Life on Delay: Making Peace With a Stutter,” committing to paper a string of words that would have caused him trouble had he tried to say them out loud. In November 2019, Hendrickson, an editor at The Atlantic, published an article about then-presidential candidate Joe Biden, who talked frequently about “beating” his childhood stutter — a bit of hyperbole that the article finally laid to rest. Biden insisted on his redemptive narrative, even though Hendrickson, who has stuttered since he was 4, could tell when Biden repeated (“I-I-I-I-I”) or blocked (“…”) on certain sounds. The article went viral, putting Hendrickson in the position of being invited to go on television — a “nightmare,” he said on MSNBC at the time, though it did lead to a flood of letters from fellow stutterers, a number of whom he interviewed for this book. “Life on Delay” traces an arc from frustration and isolation to acceptance and community, recounting a lifetime of bullying and well-meaning but ineffectual interventions and what Hendrickson calls “hundreds of awful first impressions.” When he depicts scenes from his childhood it’s often in a real-time present tense, putting us in the room with the boy he was, more than two decades before. Hendrickson also interviews people: experts, therapists, stutterers, his own parents. He calls up his kindergarten teacher, his childhood best friend and the actress Emily Blunt. He reaches out to others who have published personal accounts of stuttering, including The New Yorker’s Nathan Heller and Katharine Preston, the author of a memoir titled “Out With It.” We learn that it’s only been since the turn of the millennium or so that stuttering has been understood as a neurological disorder; that for 75 percent of children who stutter, “the issue won’t follow them to adulthood”; that there’s still disagreement over whether “disfluency” is a matter of language or motor control, because “the research is still a bit of a mess.” © 2023 The New York Times Company

Keyword: Language; Attention
Link ID: 28643 - Posted: 01.27.2023

By Diana Kwon Alan Alda was running for his life. The actor, best known for his role on the television series M*A*S*H, wasn’t on a set. This threat was real—or at least it felt that way. So when he saw a bag of potatoes in front of him, he grabbed it and threw it at his attacker. Suddenly, the scene shifted. He was in his bedroom, having lurched out of sleep, and the sack of potatoes was a pillow he’d just chucked at his wife. Acting out dreams marks a disorder that occurs during the rapid eye movement (REM) phase of sleep. Called RBD, for REM sleep behavior disorder, it affects an estimated 0.5 to 1.25 percent of the general population and is more commonly reported in older adults, particularly men. Apart from being hazardous to dreamers and their partners, RBD may foreshadow neurodegenerative disease, primarily synucleinopathies—conditions in which the protein α-synuclein (or alpha-synuclein) forms toxic clumps in the brain. Not all nocturnal behaviors are RBD. Sleepwalking and sleep talking, which occur more often during childhood and adolescence, take place during non-REM sleep. This difference is clearly distinguishable in a sleep laboratory, where clinicians can monitor stages of sleep to see when a person moves. Nor is RBD always associated with a synucleinopathy: it can also be triggered by certain drugs such as antidepressants or caused by other underlying conditions such as narcolepsy or a brain stem tumor. When RBD occurs in the absence of these alternative explanations, the chance of future disease is high. Some epidemiological studies suggest that enacted dreaming predicts a more than 80 percent chance of developing a neurodegenerative disease within the patient’s lifetime. It may also be the first sign of neurodegenerative disease, which on average shows up within 10 to 15 years after onset of the dream disorder. One of the most common RBD-linked ailments is Parkinson’s disease, characterized mainly by progressive loss of motor control. Another is Lewy body dementia, in which small clusters of α-synuclein called Lewy bodies build up in the brain, disrupting movement and cognition. A third type of synucleinopathy, multiple system atrophy, interferes with both movement and involuntary functions such as digestion. RBD is one of the strongest harbingers of future synucleinopathy, more predictive than other early markers such as chronic constipation and a diminished sense of smell.

Keyword: Parkinsons; Sleep
Link ID: 28642 - Posted: 01.25.2023

Hannah Devlin Science correspondent Widely used antidepressants cause “emotional blunting”, according to research that offers new insights into how the drugs may work and their possible side-effects. The study found that healthy volunteers became less responsive to positive and negative feedback after taking a selective serotonin reuptake inhibitor (SSRI) drug for three weeks. The “blunting” of negative emotions could be part of how the drugs help people recover from depression, but could also explain a common side-effect. The work’s senior author, Prof Barbara Sahakian of the University of Cambridge, said: “In a way, this may be in part how they work. They take away some of the emotional pain that people who experience depression feel, but unfortunately it seems that they also take away some of the enjoyment.” The findings could help patients make better informed choices about their medication, she said, but added “there is no doubt that antidepressants are beneficial” for many patients. According to the NHS more than 8.3 million patients in England received an antidepressant drug in 2021-22. SSRIs are among the most widely used, and are effective for the majority of, although not all, patients. Some people on the medication report feeling emotionally dull or no longer finding things as pleasurable, with one study suggesting this applied to 40-60% of people taking the drug. However, it has been unclear whether this symptom is a drug side-effect or a symptom of depression. The latest work suggests that the drug alone can produce emotional blunting. In the study, published in the journal Neuropsychopharmacology, 66 volunteers were given either the SSRI drug, escitalopram, or a placebo for at least 21 days before doing a set of cognitive tests. © 2023 Guardian News & Media Limited

Keyword: Depression; Emotions
Link ID: 28641 - Posted: 01.25.2023

By Darren Incorvaia The great apes do not have spoken language, but they share many gestures. Can humans like you understand those gestures too? Watch this short video and test your ability to read chimpanzee body language. What is this chimpanzee (the one scratching its arm) asking the other one to do? © 2023 The New York Times Company

Keyword: Animal Communication; Evolution
Link ID: 28640 - Posted: 01.25.2023

Niyazi Arslan Cochlear implants are among the most successful neural prostheses on the market. These artificial ears have allowed nearly 1 million people globally with severe to profound hearing loss to either regain access to the sounds around them or experience the sense of hearing for the first time. However, the effectiveness of cochlear implants varies greatly across users because of a range of factors, such as hearing loss duration and age at implantation. Children who receive implants at a younger age may may be able to acquire auditory skills similar to their peers with natural hearing. I am a researcher studying pitch perception with cochlear implants. Understanding the mechanics of this technology and its limitations can help lead to potential new developments and improvements in the future. In fully-functional hearing, sound waves enter the ear canal and are converted into neural impulses as they move through hairlike sensory cells in the cochlea, or inner ear. These neural signals then travel through the auditory nerve behind the cochlea to the central auditory areas of the brain, resulting in a perception of sound. Analysis of the world, from experts People with severe to profound hearing loss often have damaged or missing sensory cells and are unable to convert sound waves into electrical signals. Cochlear implants bypass these hairlike cells by directly stimulating the auditory nerve with electrical pulses. Cochlear implants consist of an external part wrapped behind the ear and an internal part implanted under the skin. © 2010–2023, The Conversation US, Inc.

Keyword: Hearing; Robotics
Link ID: 28639 - Posted: 01.25.2023

ByMeredith Wadman A massive data mining study has found numerous associations between common viruses like the flu and devastating neurodegenerative disorders such as Parkinson’s disease, Alzheimer’s disease, and amyotrophic lateral sclerosis (ALS, also known as Lou Gehrig’s disease). The findings expand on previous research linking individual viruses to neurological diseases. But experts caution that the study, which relied on electronic medical records rather than biological samples, merely describes correlations and doesn’t prove causation. Still, it’s “really exciting,” says Kristen Funk, a neuroimmunologist who studies Alzheimer’s at the University of North Carolina, Charlotte. Rather than homing in on, say, the relationship between herpes simplex infections and Alzheimer’s—a recent focus in her own field—“this research broadens that scope to look at different viruses and more neurodegenerative diseases.” Scientists have found connections between viruses and neurodegenerative diseases before. Previous studies uncovered ties between the influenza virus and Parkinson’s, for example, and between genital warts (caused by human papillomavirus) and dementia. A landmark project published in Science last year cemented another connection: Epidemiologists who analyzed 2 decades of data from the blood tests of 10 million U.S. soldiers reported that it’s nearly impossible to develop multiple sclerosis without first being infected with the Epstein-Barr virus—a ubiquitous pathogen long suspected of causing MS. Inspired by that paper, National Institutes of Health (NIH) researchers wondered whether they could mine other large databases to tease out more associations. They focused on viral links to six neurodegenerative diseases: Alzheimer’s, Parkinson’s, dementia, ALS, MS, and vascular dementia. (Some scientists dispute that MS and vascular dementia are neurodegenerative diseases.)

Keyword: Alzheimers; Parkinsons
Link ID: 28638 - Posted: 01.25.2023

By Chris Gorski At first glance, saliva seems like pretty boring stuff, merely a convenient way to moisten our food. But the reality is quite different, as scientists are beginning to understand. The fluid interacts with everything that enters the mouth, and even though it is 99 percent water, it has a profound influence on the flavors — and our enjoyment — of what we eat and drink. “It is a liquid, but it’s not just a liquid,” says oral biologist Guy Carpenter of King’s College London. Scientists have long understood some of saliva’s functions: It protects the teeth, makes speech easier and establishes a welcoming environment for foods to enter the mouth. But researchers are now finding that saliva is also a mediator and a translator, influencing how food moves through the mouth and how it sparks our senses. Emerging evidence suggests that interactions between saliva and food may even help to shape which foods we like to eat. The substance is not very salty, which allows people to taste the saltiness of a potato chip. It’s not very acidic, which is why a spritz of lemon can be so stimulating. The fluid’s water and salivary proteins lubricate each mouthful of food, and its enzymes such as amylase and lipase kickstart the process of digestion. This wetting also dissolves the chemical components of taste, or tastants, into saliva so they can travel to and interact with the taste buds. Through saliva, says Jianshe Chen, a food scientist at Zhejiang Gongshang University in Hangzhou, China, “we detect chemical information of food: the flavor, the taste.” © 2023 Annual Reviews

Keyword: Chemical Senses (Smell & Taste)
Link ID: 28637 - Posted: 01.25.2023

By Brandon Keim When Lauren Strohacker received her second Covid-19 vaccine dose in the spring of 2021, she rejoiced. It meant she could see her friends again, go to concerts and live with far less fear that an infection might leave her physically or financially devastated. But it became a bittersweet memory. Not long after Ms. Strohacker, an artist based in Knox County, Tenn., returned home from the vaccination site, she read an article about monkeys used in testing Covid vaccines. “I thought, I’m afraid of a stupid needle,” she said. “And these animals have to deal with this all the time.” She reflected on how her newfound freedom, and quite possibly her health, came at the expense of animals suffering or dying to develop the vaccines. Merely being grateful for those animals seemed insufficient; Ms. Strohacker wanted to give something tangible in return. A little online research returned the National Anti-Vivisection Society’s sanctuary fund, which supports the care of retired lab animals. She made a small donation. “To give thanks was the very least I could do,” Ms. Strohacker said. Her gesture embodies a voice that is not often heard in debates about the use of animals in biomedical research. These tend to be polarized between opponents of the research, who claim that it is unethical and the benefits are overstated, and proponents who argue that the benefits are enormous and justify the harms to animals. The advancement of animal-free methods for developing drugs and testing product safety does raise the possibility that, at least in some cases, the use of animals can be avoided. But it will take years for that to happen, and few researchers think the use of animals will cease altogether. So long as animals are used, then, the question remains: What do people owe them? © 2023 The New York Times Company

Keyword: Animal Rights
Link ID: 28636 - Posted: 01.25.2023

By Alessandra Buccella, Tomáš Dominik  Imagine you are shopping online for a new pair of headphones. There is an array of colors, brands and features to look at. You feel that you can pick any model that you like and are in complete control of your decision. When you finally click the “add to shopping cart” button, you believe that you are doing so out of your own free will. But what if we told you that while you thought that you were still browsing, your brain activity had already highlighted the headphones you would pick? That idea may not be so far-fetched. Though neuroscientists likely could not predict your choice with 100 percent accuracy, research has demonstrated that some information about your upcoming action is present in brain activity several seconds before you even become conscious of your decision. As early as the 1960s, studies found that when people perform a simple, spontaneous movement, their brain exhibits a buildup in neural activity—what neuroscientists call a “readiness potential”—before they move. In the 1980s, neuroscientist Benjamin Libet reported this readiness potential even preceded a person’s reported intention to move, not just their movement. In 2008 a group of researchers found that some information about an upcoming decision is present in the brain up to 10 seconds in advance, long before people reported making the decision of when or how to act. Advertisement These studies have sparked questions and debates. To many observers, these findings debunked the intuitive concept of free will. After all, if neuroscientists can infer the timing or choice of your movements long before you are consciously aware of your decision, perhaps people are merely puppets, pushed around by neural processes unfolding below the threshold of consciousness. But as researchers who study volition from both a neuroscientific and philosophical perspective, we believe that there’s still much more to this story. We work with a collaboration of philosophers and scientists to provide more nuanced interpretations—including a better understanding of the readiness potential—and a more fruitful theoretical framework in which to place them. The conclusions suggest “free will” remains a useful concept, although people may need to reexamine how they define it. © 2023 Scientific American

Keyword: Consciousness
Link ID: 28635 - Posted: 01.18.2023

By Dennis Overbye If you could change the laws of nature, what would you change? Maybe it’s that pesky speed-of-light limit on cosmic travel — not to mention war, pestilence and the eventual asteroid that has Earth’s name on it. Maybe you would like the ability to go back in time — to tell your teenage self how to deal with your parents, or to buy Google stock. Couldn’t the universe use a few improvements? That was the question that David Anderson, a computer scientist, enthusiast of the Search for Extraterrestrial Intelligence (SETI), musician and mathematician at the University of California, Berkeley, recently asked his colleagues and friends. In recent years the idea that our universe, including ourselves and all of our innermost thoughts, is a computer simulation, running on a thinking machine of cosmic capacity, has permeated culture high and low. In an influential essay in 2003, Nick Bostrom, a philosopher at the University of Oxford and director of the Institute for the Future of Humanity, proposed the idea, adding that it was probably an easy accomplishment for “technologically mature” civilizations wanting to explore their histories or entertain their offspring. Elon Musk, who, for all we know, is the star of this simulation, seemed to echo this idea when he once declared that there was only a one-in-a-billion chance that we lived in “base reality.” It’s hard to prove, and not everyone agrees that such a drastic extrapolation of our computing power is possible or inevitable, or that civilization will last long enough to see it through. But we can’t disprove the idea either, so thinkers like Dr. Bostrom contend that we must take the possibility seriously. In some respects, the notion of a Great Simulator is redolent of a recent theory among cosmologists that the universe is a hologram, its margins lined with quantum codes that determine what is going on inside. A couple of years ago, pinned down by the coronavirus pandemic, Dr. Anderson began discussing the implications of this idea with his teenage son. If indeed everything was a simulation, then making improvements would simply be a matter of altering whatever software program was running everything. “Being a programmer, I thought about exactly what these changes might involve,” he said in an email. © 2023 The New York Times Company

Keyword: Consciousness
Link ID: 28634 - Posted: 01.18.2023

By Daryl Austin My three young daughters like to watch pets doing silly things. Almost daily, they ask to see animal video clips on my phone and are quickly entertained. But once my 7-year-old lets out a belly laugh, the laughter floodgates are opened and her two sisters double over as well. This is just what science would predict. “Laughter is a social phenomenon,” says Sophie Scott, a neuroscientist at University College London who has studied laughter and other human reactions for more than two decades. Scott co-wrote a study showing how the brain responds to the sound of laughter by preparing one’s facial muscles to join in, laying the foundation for laughs to spread from person to person. “Contagious laughter demonstrates affection and affiliation,” Scott says. “Even being in the presence of people you expect to be funny will prime laughter within you.” It’s like yawning Scientists have yet to definitively find a funny bone, but they are revealing nuances about the laugh impulse. Laughter’s positive psychological and physiological responses include lessening depression and anxiety symptoms, increasing feelings of relaxation, improving cardiovascular health, releasing endorphins that boost mood and even increasing tolerance for pain. Laughing has also been shown to lower stress levels. “Cortisol is a stress hormone that laughter lowers,” says Scott, adding that anticipation of laughter also “drops your adrenaline” and the body’s heightened fight-or-flight response. “All of these things contribute to you feeling better when you’ve been laughing,” she says. Because humans are wired to mirror one another, laughs spread around a room just like yawns, says Lauri Nummenmaa, a brain researcher and professor at Aalto University School of Science in Finland whose work appears in a recent special issue on laughter in the journal Royal Society.

Keyword: Emotions
Link ID: 28633 - Posted: 01.18.2023

Miryam Naddaf Researchers have made transgenic ants whose antennae glow green under a microscope, revealing how the insects’ brains process alarming smells. The findings identify three unique brain regions that respond to alarm signals. In these areas, called glomeruli, the ants’ nerve endings intersect. The work was posted on the bioRxiv preprint server on 29 December 20221 and has not yet been peer reviewed. “Ants are like little walking chemical factories,” says study co-author Daniel Kronauer, a biologist at the Rockefeller University in New York City. Previous research has focused on identifying the chemicals that ants release or analysing the insects’ behavioural responses to these odours, but “how ants can actually smell the pheromones is really only now becoming a little bit clearer”, says Kronauer. “This is the first time that, in a social insect, a particular glomerulus has been associated very strongly with a particular behaviour,” he adds. Smelly signals Ants are social animals that communicate with each other by releasing scented chemicals called pheromones. The clonal raider ants (Ooceraea biroi) that the researchers studied are blind. “They basically live in a world of smells,” says Kronauer. “So the vast amount of their social behaviour is regulated by these chemical compounds.” When an ant perceives danger, it releases alarm pheromones from a gland in its head to warn its nestmates. Other ants respond to this signal by picking up their larvae and evacuating the nest. “Instead of having dedicated brain areas for face recognition or language processing, ants have a massively expanded olfactory system,” says Kronauer. The researchers created transgenic clonal raider ants by injecting the insects’ eggs with a vector carrying a gene for a green fluorescent protein combined with one that expresses a molecule that indicates calcium activity in the brain. © 2023 Springer Nature Limited

Keyword: Chemical Senses (Smell & Taste)
Link ID: 28632 - Posted: 01.18.2023

Kaitlyn Radde Socially isolated older adults have a 27% higher chance of developing dementia than older adults who aren't, a new study by Johns Hopkins researchers found. "Social connections matter for our cognitive health, and it is potentially easily modifiable for older adults without the use of medication," Dr. Thomas Cudjoe, an assistant professor of medicine at Johns Hopkins and a senior author of the study, said in a news release. Published in the Journal of the American Geriatrics Society, the study tracked 5,022 dementia-free U.S. adults who were 65 or older – with an average age of 76 – and not living in a residential care facility. About 23% of participants were socially isolated. Social isolation is defined as having few relationships and few people to interact with regularly. The study measured this based on whether or not participants lived alone, talked about "important matters" with two or more people in the past year, attended religious services or participated in social events. Participants were assigned one point for each item, and those who scored a zero or one were classified as socially isolated. Over the course of nine years, researchers periodically administered cognitive tests. Overall, about 21% of the study participants developed dementia. But among those were who were socially isolated, about 26% developed dementia – compared to slightly less than 20% for those who were not socially isolated. The study did not find significant differences by race or ethnicity. However, more than 70% of the participants in the study were white – with particularly small sample sizes of Hispanic, Asian and Native participants – and the authors call for further research on the topic. © 2023 npr

Keyword: Alzheimers
Link ID: 28631 - Posted: 01.18.2023

By Jan Hoffman PHILADELPHIA — Over a matter of weeks, Tracey McCann watched in horror as the bruises she was accustomed to getting from injecting fentanyl began hardening into an armor of crusty, blackened tissue. Something must have gotten into the supply. Switching corner dealers didn’t help. People were saying that everyone’s dope was being cut with something that was causing gruesome, painful wounds. “I’d wake up in the morning crying because my arms were dying,” Ms. McCann, 39, said. In her shattered Philadelphia neighborhood, and increasingly in drug hot zones around the country, an animal tranquilizer called xylazine — known by street names like “tranq,” “tranq dope” and “zombie drug” — is being used to bulk up illicit fentanyl, making its impact even more devastating. Xylazine causes wounds that erupt with a scaly dead tissue called eschar; untreated, they can lead to amputation. It induces a blackout stupor for hours, rendering users vulnerable to rape and robbery. When people come to, the high from the fentanyl has long since faded and they immediately crave more. Because xylazine is a sedative and not an opioid, it resists standard opioid overdose reversal treatments. More than 90 percent of Philadelphia’s lab-tested dope samples were positive for xylazine, according to the most recent data. “It’s too late for Philly,” said Shawn Westfahl, an outreach worker with Prevention Point Philadelphia, a 30-year-old health services center in Kensington, the neighborhood at the epicenter of the city’s drug trade. “Philly’s supply is saturated. If other places around the country have a choice to avoid it, they need to hear our story.” A study published in June detected xylazine in the drug supply in 36 states and the District of Columbia. In New York City, xylazine has been found in 25 percent of drug samples, though health officials say the actual saturation is certainly greater. In November, the Food and Drug Administration issued a nationwide four-page xylazine alert to clinicians. © 2023 The New York Times Company

Keyword: Drug Abuse
Link ID: 28630 - Posted: 01.14.2023

Holly Else An artificial-intelligence (AI) chatbot can write such convincing fake research-paper abstracts that scientists are often unable to spot them, according to a preprint posted on the bioRxiv server in late December1. Researchers are divided over the implications for science. “I am very worried,” says Sandra Wachter, who studies technology and regulation at the University of Oxford, UK, and was not involved in the research. “If we’re now in a situation where the experts are not able to determine what’s true or not, we lose the middleman that we desperately need to guide us through complicated topics,” she adds. The chatbot, ChatGPT, creates realistic and intelligent-sounding text in response to user prompts. It is a ‘large language model’, a system based on neural networks that learn to perform a task by digesting huge amounts of existing human-generated text. Software company OpenAI, based in San Francisco, California, released the tool on 30 November, and it is free to use. Since its release, researchers have been grappling with the ethical issues surrounding its use, because much of its output can be difficult to distinguish from human-written text. Scientists have published a preprint2 and an editorial3 written by ChatGPT. Now, a group led by Catherine Gao at Northwestern University in Chicago, Illinois, has used ChatGPT to generate artificial research-paper abstracts to test whether scientists can spot them. The researchers asked the chatbot to write 50 medical-research abstracts based on a selection published in JAMA, The New England Journal of Medicine, The BMJ, The Lancet and Nature Medicine. They then compared these with the original abstracts by running them through a plagiarism detector and an AI-output detector, and they asked a group of medical researchers to spot the fabricated abstracts. © 2023 Springer Nature Limited

Keyword: Language; Intelligence
Link ID: 28629 - Posted: 01.14.2023

By Carolyn Wilke Mammals in the ocean swim through a world of sound. But in recent decades, humans have been cranking up the volume, blasting waters with noise from shipping, oil and gas exploration and military operations. New research suggests that such anthropogenic noise may make it harder for dolphins to communicate and work together. When dolphins cooperated on a task in a noisy environment, the animals were not so different from city dwellers on land trying to be heard over a din of jackhammers and ambulance sirens. They yelled, calling louder and longer, researchers reported Thursday in the journal Current Biology. “Even then, there’s a dramatic increase in how often they fail to coordinate,” said Shane Gero, a whale biologist at Carleton University in Ottawa who wasn’t part of the work. The effect of increasing noise was “remarkably clear.” Scientists worked with a dolphin duo, males named Delta and Reese, at an experimental lagoon at the Dolphin Research Center in the Florida Keys. The pair were trained to swim to different spots in their enclosure and push a button within one second of each other. “They’ve always been the most motivated animals. They were really excited about doing the task,” said Pernille Sørensen, a biologist and Ph.D. candidate at the University of Bristol in England. The dolphins talked to each other using whistles and often whistled right before pressing the button, she said. Ms. Sørensen’s team piped in sounds using underwater speakers. Tags, stuck behind the animals’ blowholes, captured what the dolphins heard and called to each other as well as their movements. Through 200 trials with five different sound environments, the team observed how the dolphins changed their behavior to compensate for loud noise. The cetaceans turned their bodies toward each other and paid greater attention to each other’s location. At times, they nearly doubled the length of their calls and amplified their whistles, in a sense shouting, to be heard above cacophonies of white noise or a recording of a pressure washer. © 2023 The New York Times Company

Keyword: Animal Communication; Hearing
Link ID: 28628 - Posted: 01.14.2023