By Shaena Montanari Just as romantic partners exhibit more similar brain waves than do strangers when, say, drawing on an Etch A Sketch toy together, animal pairs also show neural synchrony during social interactions and cooperation tasks. “Neural synchrony is something that happens in these minute-to-minute engagements that you have with another individual,” says Zoe Donaldson, associate professor of behavioral neuroscience at the University of Colorado Boulder. But over time, too, pairs in a relationship learn to infer what their partner is going to do, she adds. In prairie voles, at least, that learning process may unfold at the molecular level in the form of “transcriptional synchrony,” according to a preprint Donaldson and her colleagues posted on bioRxiv in November. Prairie voles are socially monogamous, and after two of them bond, gene-expression patterns in their nucleus accumbens—a forebrain region linked to reward and social interaction—start to align. It remains unclear whether this transcriptional synchrony causes pair bonding or only correlates with it, she adds, but in the meantime, it offers researchers a new place to hunt for the basis of these strong social ties. This new study “pushes the limits of what’s possible” technically, says Robert Froemke, professor in New York University’s Neuroscience Institute and otolaryngology department, who was not involved in the study. Though the existence of neural synchrony logically suggests that there may also be shared patterns of gene expression, “it’s still remarkable to actually have it documented,” he says. The new preprint offers the first evidence of transcriptional synchrony in prairie voles, Donaldson says, but a 2020 study revealed that fighting pairs of Betta splendens fish show a strong correlation of gene expression after 60 minutes of fighting, and only a weak correlation after 20 minutes. © 2025 Simons Foundation

Keyword: Sexual Behavior
Link ID: 29630 - Posted: 01.15.2025

By Giorgia Guglielmi Amid the rising buzz around Ozempic and similar weight-loss drugs, a group of 58 researchers is challenging the way obesity is defined and diagnosed, arguing that current methods fail to capture the complexity of the condition. They offer a more nuanced approach. The group’s revised definition, published in The Lancet Diabetes & Endocrinology1 on 14 January, focuses on how excess body fat, a measure called adiposity, affects the body, rather than relying only on body mass index (BMI), which links a person’s weight to their height. They propose two categories: preclinical obesity, when a person has extra body fat but their organs work normally, and clinical obesity, when excess fat harms the body’s organs and tissues. This shift could improve clinical care, public-health policies and societal attitudes toward obesity, says Elisabeth van Rossum, an endocrinologist at the Erasmus University Medical Center Rotterdam in the Netherlands. “Now the idea is, eat less, move more, and you’ll lose weight,” says van Rossum, who wasn’t involved in the work. Although a healthy lifestyle is important, she adds, “if it would be so simple, we wouldn’t have an epidemic, and this paper is an excellent contribution to the discussion about the complexity of obesity”. Global problem More than 1 billion people worldwide live with obesity, and the condition is linked to about 5 million deaths every year2 from disorders such as diabetes and cardiovascular disease. Because it is easy to measure and compare, BMI has long been used as a tool to diagnose obesity. But it doesn’t offer a full picture of a person’s health, because it doesn’t account for differences in body composition, such as muscle versus fat. © 2025 Springer Nature Limited

Keyword: Obesity
Link ID: 29629 - Posted: 01.15.2025

By Jennifer Kahn Here’s a strange story: One day two summers ago, I woke up because my arms — both of them — hurt. Not the way they do when you’ve slept in a funny position, but as if the tendons in my forearms and hands were moving through mud. What felt like sharp electric shocks kept sparking in my fingers and sometimes up the inside of my biceps and across my chest. Holding anything was excruciating: a cup, a toothbrush, my phone. Even doing nothing was miserable. It hurt when I sat with my hands in my lap, when I stood, when I lay flat on the bed or on my side. The slightest pressure — a bedsheet, a watch band, a bra strap — was intolerable. It was August, and every doctor seemed to be away on vacation. The ones I did manage to see were politely stumped. It wasn’t carpal tunnel, tennis elbow or any other injury they could identify. I did nothing unusual the day before: an hour of work on my laptop, followed by a visit with a friend. We sat in her backyard and talked. For the first few weeks, I could barely sleep. Over the following months, I lost weight — almost a pound a week. I couldn’t drive, or cook, or use my laptop for work, or even hold a book or a pen. I would have been bored, except the pain was so tiring that I could barely function. I spent the days shuffling around the house listening to audiobooks and doing voice-to-text searches for “nerve pain arms” with my phone flat on the table, then carefully, painfully, scrolling through the results. I think we’re past the point where I have to explain that chronic pain is not the result of imbalanced humors or a wandering uterus or possession by demons. But for more modern skeptics, this is where I should add that chronic pain also isn’t just “all in your head” or “not really that bad” — or any of the other ways in which people who suffer from it are still regularly gaslit and dismissed. Personally, I never had to contend with not being believed, almost certainly because I’m an otherwise healthy, reasonably well-off white woman with a clean medical history and no significant record of anxiety or depression. Instead, I was taken seriously. A whole gamut of tests was run. My wrists were X-rayed. I had an M.R.I. on my cervical spine. Each new doctor ordered new blood tests: some for vitamin deficiencies, others for autoimmune diseases like rheumatoid arthritis. © 2025 The New York Times Company

Keyword: Pain & Touch
Link ID: 29628 - Posted: 01.15.2025

By Meghan Rosen Baby Boomers may drive a bigger-than-expected boom in dementia cases. By 2060, 1 million U.S. adults per year will develop dementia, scientists predict January 13 in Nature Medicine. Dementia is a broad term encompassing many symptoms, including memory, reasoning and language difficulties that interfere with people’s daily lives. Researchers estimate that it currently affects more than 6 million people in the United States. “This is a huge problem,” says Josef Coresh, an epidemiologist at New York University’s Grossman School of Medicine. A rise in the projected number of dementia cases is not surprising, given the aging U.S. population ­­— but the extent of the rise stands out, he says. His team predicts that 42 percent of people in the United States who are over 55 years old will develop dementia sometime during their lifetime. That’s about double the percentage estimated by previous researchers. Coresh’s new estimate is based on a study population that’s larger — more than 15,000 people — and more diverse than earlier work. His team followed participants for years, in some cases decades, using several methods to identify dementia cases. They pored over hospital and death records, evaluated participants in person and screened them by phone. For the last decade, the researchers have been calling participants twice a year, Coresh says. That gave the team a window into people’s lives, revealing dementia cases that might otherwise have gone unreported. Though the team focused on dementia in people over age 55, risk doesn’t typically start ticking up for decades. And some populations were at greater risk than others, including women, Black people and those with a particular gene variant linked to Alzheimer’s disease. © Society for Science & the Public 2000–2025.

Keyword: Alzheimers
Link ID: 29627 - Posted: 01.15.2025

By Mitch Leslie Scientists think sleep is the brain’s rinse cycle, when fluid percolating through the organ flushes out chemical waste that accumulated while we were awake. But what propels this circulation has been uncertain. A study of mice, reported today in Cell, suggests regular contractions of blood vessels in the brain, stimulated by the periodic release of a chemical cousin of adrenaline, push the fluid along. “This is excellent science,” says neuroscientist Suzana Herculano-Houzel of Vanderbilt University, who wasn’t connected to the study. “They put a number of pieces of evidence together that tell a pretty compelling story.” The scientists also found that the sleep drug zolpidem, better known as Ambien, impedes the blood vessel oscillations and the fluid flow they promote, implying it could hamper cleansing. The finding could help researchers create new sleep aids that preserve this brain-scrubbing function. The brain lacks the lymphatic vessels that collect and move fluid in other parts of the body. But in 2012, neuroscientist Maiken Nedergaard of the University of Rochester Medical Center and colleagues identified an alternative drainage system in which cerebrospinal fluid, the liquid bathing the brain, seeps through the organ via tiny passages alongside blood vessels, sweeping away metabolic refuse and other unwanted molecules. Fluid flow through this so-called glymphatic system ramps up during sleep, they also reported. Studies from 
Nedergaard’s group and others suggest vigorous glymphatic clearance is beneficial: Circulation falters in Alzheimer’s disease and other neurodegenerative illnesses. Some researchers have challenged parts of this picture, however; a 2024 study, for example, suggested waste clearance is actually faster during waking than during sleep. In the new research, Nedergaard and her team wanted to pin down what keeps cerebrospinal fluid moving through the brain. But studying the mouse glymphatic system often involves anesthetizing the rodents, she says, which is very different from natural sleep. To avoid this problem, the scientists surgically implanted mice with electrodes and fiber optic filaments. Although the rodents are tethered to a set of cables, they can fall asleep normally while researchers track blood volume, electrical activity, and chemical levels and use light transmitted through the fiber optic lines to activate certain groups of neurons.

Keyword: Sleep
Link ID: 29626 - Posted: 01.11.2025

By Roni Caryn Rabin Water fluoridation is widely seen as one of the great public health achievements of the 20th century, credited with substantially reducing tooth decay. But there has been growing controversy among scientists about whether fluoride may be linked to lower I.Q. scores in children. A comprehensive federal analysis of scores of previous studies, published this week in JAMA Pediatrics, has added to those concerns. It found a significant inverse relationship between exposure levels and cognitive function in children. Higher fluoride exposures were linked to lower I.Q. scores, concluded researchers working for the National Institute of Environmental Health Sciences. None of the studies included in the analysis were conducted in the United States, where recommended fluoridation levels in drinking water are very low. At those amounts, evidence was too limited to draw definitive conclusions. Observational studies cannot prove a cause-and-effect relationship. Yet in countries with much higher levels of fluoridation, the analysis also found evidence of what scientists call a dose-response relationship, with I.Q. scores falling in lock step with increasing fluoride exposure. Children are exposed to fluoride through many sources other than drinking water: toothpaste, dental treatments and some mouthwashes, as well as black tea, coffee and certain foods, such as shrimp and raisins. Some drugs and industrial emissions also contain fluoride. For every one part per million increase in fluoride in urinary samples, which reflect total exposures from water and other sources, I.Q. points in children decreased by 1.63, the analysis found. “There is concern that pregnant women and children are getting fluoride from many sources,” said Kyla Taylor, an epidemiologist at the institute and the report’s lead author, “and that their total fluoride exposure is too high and may affect fetal, infant and child neurodevelopment.” © 2025 The New York Times Company

Keyword: Intelligence; Development of the Brain
Link ID: 29625 - Posted: 01.11.2025

By Kristel Tjandra Close your eyes and picture an apple—what do you see? Most people will conjure up a vivid image of the fruit, but for the roughly one in 100 individuals with aphantasia, nothing will appear in the mind’s eye at all. Now, scientists have discovered that in people with this inability to form mental images, visual processing areas of the brain still light up when they try to do so. The study, published today in Current Biology, suggests aphantasia is not caused by a complete deficit in visual processing, as researchers have previously proposed. Visual brain areas are still active when aphantasic people are asked to imagine—but that activity doesn’t translate into conscious experience. The work offers new clues about the neurological differences underlying this little-explored condition. The study authors “take a very strong, mechanistic approach,” says Sarah Shomstein, a vision scientist at George Washington University who was not involved in the study. “It was asking the right questions and using the right methods.” Some scientists suspect aphantasia may be caused by a malfunction in the primary visual cortex, the first area in the brain to process images. “Typically, primary cortex is thought to be the engine of visual perception,” says Joel Pearson, a neuroscientist at the University of New South Wales Sydney who co-led the study. “If you don’t have activity there, you’re not going to have perceptual consciousness.” To see what was going on in this region in aphantasics, the team used functional magnetic resonance imaging to measure the brain activity of 14 people with aphantasia and 18 neurotypical controls as they repeatedly saw two simple patterns, made up of either green vertical lines or red horizontal lines. They then repeated the experiment, this time asking participants to simply imagine the two images.

Keyword: Attention; Vision
Link ID: 29624 - Posted: 01.11.2025

By Christina Caron Barrie Miskin was newly pregnant when she noticed her appearance was changing. Dark patches bloomed on her skin like watercolor ink. A “thicket” of hairs sprouted on her upper lip and chin. The outside world was changing, too: In her neighborhood of Astoria, Queens, bright lights enveloped objects in a halo, blurring her vision. Co-workers and even her doctors started to seem like “alien proxies” of themselves, Ms. Miskin, 46, said. “I felt like I was viewing the world through a pane of dirty glass,” she added. Yet Ms. Miskin knew it was all an illusion, so she sought help. Welcome to Psych 101, a new monthly column that explores mental health terms and trends that are worthy of a bigger conversation. If there is a subject you’d like to see covered, please drop us a line at Psych101@nytimes.com. It took more than a year of consulting with mental health specialists before Ms. Miskin finally found an explanation for her symptoms: She was diagnosed with a dissociative condition called depersonalization/derealization disorder, or D.D.D. Before her pregnancy, Ms. Miskin had stopped taking antidepressants. Her new psychiatrist said the symptoms could have been triggered by months of untreated depression that followed. While Ms. Miskin felt alone in her mystery illness, she wasn’t. Tens of thousands of posts on social media reference depersonalization or derealization, with some likening the condition to “living in a movie or a dream” or “observing the world through a fog.” People who experience depersonalization can feel as though they are detached from their mind or body. Derealization, on the other hand, refers to feeling detached from the environment, as though the people and things in the world are unreal. Those who are living with D.D.D. are “painfully aware” that something is amiss, said Elena Bezzubova, a psychoanalyst who specializes in treating the condition. It’s akin to seeing an apple and feeling that it is so strange it doesn’t seem real, even though you know that it is, she added. The disorder is thought to occur in about 1 to 2 percent of the population, but it’s possible for anyone to experience fleeting symptoms. © 2025 The New York Times Company

Keyword: Attention
Link ID: 29623 - Posted: 01.11.2025

By Laura Sanders Recovery from PTSD comes with key changes in the brain’s memory system, a new study finds. These differences were found in the brains of 19 people who developed post-traumatic stress disorder after the 2015 terrorist attacks in Paris — and then recovered over the following years. The results, published January 8 in Science Advances, point to the complexity of PTSD, but also to ways that brains can reshape themselves as they recover. With memory tasks and brain scans, the study provides a cohesive look at the recovering brain, says cognitive neuroscientist Vishnu Murty of the University of Oregon in Eugene. “It’s pulled together a lot of pieces that were floating around in the field.” On the night of November 13, 2015, terrorists attacked a crowded stadium, a theater and restaurants in Paris. In the years after, PTSD researchers were able to study some of the people who endured that trauma. Just over half the 100 people who volunteered for the study had PTSD initially. Of those, 34 still had the disorder two to three years later; 19 had recovered by two to three years. People who developed PTSD showed differences in how their brains handled intrusive memories, laboratory-based tests of memory revealed. Participants learned pairs of random words and pictures — a box of tissues with the word “work,” for example. PTSD involves pairs of associated stimuli too, though in much more complicated ways. A certain smell or sound, for instance, can be linked with the memory of trauma. © Society for Science & the Public 2000–2025.

Keyword: Learning & Memory; Stress
Link ID: 29622 - Posted: 01.11.2025

By Apoorva Mandavilli The snake struck 11-year-old Beatrice Ndanu Munyoki as she sat on a small stone, which lay atop a larger one, watching the family’s eight goats. She was idly running her fingers through the dirt when she saw a red head dart from between the stones and felt a sharp sting on her right index finger. Never a crier, she ran to her father, David Mutunga, who was building a fence. He cut the cloth belt on her dress into strips with a machete, tied her arm in three places and rushed her to a hospital 30 minutes away on a motorcycle taxi. As the day stretched on, her finger grew darker, but the hospital in Mwingi, a small town in Kenya, had no antidote for that kind of venom. Finally that evening in November 2023, she was taken by ambulance to another hospital and injected with antivenom. When the finger blistered, swelled and turned black despite a second dose the next day, “I understood that they will now remove that part,” Mr. Mutunga said with tears in his eyes. Beatrice’s finger was amputated. In Kenya, India, Brazil and dozens of other countries, snakes vie for the same land, water and sometimes food as people, with devastating consequences. Deforestation, human sprawl and climate change are exacerbating the problem. According to official estimates, about five million people are bitten by snakes each year. About 120,000 die, and some 400,000 lose limbs to amputation. The real toll is almost certainly much higher. Estimates are generally based on hospital records, but most snakebites occur in rural areas, far from dispensaries that stock antivenom and among people too poor to afford treatment. “We don’t actually know the burden of snakebite for most countries of the world,” said Nicholas Casewell, a snake researcher at the Liverpool School of Tropical Medicine. © 2025 The New York Times Company

Keyword: Neurotoxins
Link ID: 29621 - Posted: 01.08.2025

By Angie Voyles Askham Old age is the best predictor of Alzheimer’s disease, Parkinson’s disease and many other neurodegenerative conditions. And yet, as deeply studied as those conditions are, the process of healthy brain aging is not well understood. Without that knowledge, “how can we possibly fix something that goes wrong because of it?” asks Courtney Glavis-Bloom, senior staff scientist at the Salk Institute for Biological Sciences. “We don’t have the basics. It’s like running before we walk.” That said, mounting evidence suggests that aging takes a particular toll on non-neuronal and white-matter cells in mice. For example, white-matter cells display more differentially expressed genes in aged mice than in younger ones, according to a 2023 single-cell analysis of the frontal cortex and striatum. And glia present in white matter show accelerated aging when compared with cells in the cortex across 15 different brain regions, another 2023 mouse study revealed. “Different brain regions show totally different trajectories regarding aging,” says Andreas Keller, head of the Department of Clinical Bioinformatics at the Helmholtz Institute for Pharmaceutical Research Saarland, who worked on the latter study. Some of the cell types with the most extensive aging-related changes in gene expression occur in a small region of the hypothalamus, according to a new single-cell mouse atlas, the largest and broadest to date. Rare neuronal and non-neuronal cell populations within this “hot spot” are particularly vulnerable to the aging process, says Hongkui Zeng, executive vice president and director of the Allen Institute for Brain Science, who led the work. “This demonstrates the power of using the cell-type-specific approach that will identify highly susceptible, rare populations of interest in the brain,” she says. © 2025 Simons Foundation

Keyword: Alzheimers
Link ID: 29620 - Posted: 01.08.2025

Kat Lay Global health correspondent Pills that prevent Alzheimer’s disease or blunt its effects are on the horizon, as the fight against dementia enters a “new era”, experts have said. Scientific advances were on the cusp of producing medicines that could be used even in the most remote and under-resourced parts of the world, thereby “democratising” care, said Jeff Cummings, professor of brain science and health at the University of Nevada. An estimated 50 million people live with dementia globally, more than two-thirds of them in low- and middle-income countries. In 2024, the first drugs that can change the course of Alzheimer’s disease entered the market. Eisai and Biogen’s lecanemab and Eli Lilly’s donanemab were approved by medicine watchdogs in many western countries, including the UK and US. “I’m just so excited about this,” said Cummings. “We are truly in a new era. We have opened the door to understanding and manipulating the biology of Alzheimer’s disease for the benefit of our patients.” Cummings conceded that high prices, complicated administration techniques and requirements for advanced technology to monitor patients meant that those newly approved drugs were “not going to be made widely available in the world”. Neither is yet available on the NHS in the UK because of the high cost – about £20,000 to £25,000 a year for each patient. They require additional tests and scans that would probably double that figure. But Cummings said they offered evidence of how to target dementia and “this learning is going to open the door to new therapies of many types, and those drugs can be exported around the world”. There are currently 127 drugs in trials for Alzheimer’s disease. © 2025 Guardian News & Media Limited

Keyword: Alzheimers
Link ID: 29619 - Posted: 01.08.2025

By Joshua Cohen For decades, scientists have been trying to develop therapeutics for people living with Alzheimer’s disease, a progressive neurodegenerative disease that is characterized by cognitive decline. Given the global rise in cases, the stakes are high. A study published in The Lancet Public Health reports that the number of adults living with dementia worldwide is expected to nearly triple, to 153 million in 2050. Alzheimer’s disease is a dominant form of dementia, representing 60 to 70 percent of cases. Recent approvals by the Food and Drug Administration have focused on medications that shrink the sticky brain deposits of a protein called amyloid beta. The errant growth of this protein is responsible for triggering an increase in tangled threads of another protein called tau and the development of Alzheimer’s disease — at least according to the dominant amyloid cascade hypothesis, which was first proposed in 1991. Over the past few years, however, data and drugs associated with the hypothesis have been mired in various controversies relating to data integrity, regulatory approval, and drug safety. Nevertheless, the hypothesis still dominates research and drug development. According to Science, in fiscal year 2021 to 2022, the National Institutes of Health spent some $1.6 billion on projects that mention amyloids, about 50 percent of the agency’s overall Alzheimer’s funding. And a close look at the data for recently approved drugs suggests the hypothesis is not wrong, so much as incomplete. A few years ago, Matthew Schrag, a neurologist at Vanderbilt University, discovered possible image tampering in papers that supported the hypothesis, including in an influential 2006 Nature study that was eventually retracted. At roughly the same time, the FDA had been greenlighting medications that target amyloid beta.

Keyword: Alzheimers
Link ID: 29618 - Posted: 01.08.2025

Jon Hamilton A single dose of the anesthetic ketamine can provide weeks of relief from severe depression. One reason may be that the drug causes long-term changes to a brain circuit involved in "giving up," a team reports in the journal Neuron. The team found that in zebrafish, ketamine alters this circuit in a way that causes the fish to persevere in the face of adversity rather than becoming passive. This resilience appears linked to brain cells called astrocytes, which play a central role in the "giving up" circuit. "Something happens within those cells that changes their response" to adversity, says Misha Ahrens, an author of the study and a senior group leader at HHMI's Janelia Research Campus. "We don't know what that is yet." But if scientists can figure it out, they might be able to develop more effective versions of ketamine and other psychiatric drugs, Ahrens says. The research involved the larval zebrafish, which is smaller than a grain of rice and looks like a tadpole. "It's transparent, so you can basically see what's going on in the entire brain all at once," says Alex Chen of Harvard University, another member of the team. For the experiment, the fish had to be kept stationary so scientists could monitor its brain. "But we still want it to feel like it's swimming through a virtual world," Chen says. The team did this by projecting images indicating forward movement when the animal swished its tail. Then they switched to images showing no progress, no matter what the fish did. © 2025 npr

Keyword: Depression
Link ID: 29617 - Posted: 01.08.2025

By McKenzie Prillaman A peek into living tissue from human hippocampi, a brain region crucial for memory and learning, revealed relatively few cell-to-cell connections for the vast number of nerve cells. But signals sent via those sparse connections proved extremely reliable and precise, researchers report December 11 in Cell. One seahorse-shaped hippocampus sits deep within each hemisphere of the mammalian brain. In each hippocampus’s CA3 area, humans have about 1.7 million nerve cells called pyramidal cells. This subregion is thought to be the most internally connected part of the brain in mammals. But much information about nerve cells in this structure has come from studies in mice, which have only 110,000 pyramidal cells in each CA3 subregion. Previously discovered differences between mouse and human hippocampi hinted that animals with more nerve cells may have fewer connections — or synapses — between them, says cellular neuroscientist Peter Jonas of the Institute of Science and Technology Austria in Klosterneuburg. To see if this held true, he and his colleagues examined tissue taken with consent from eight patients who underwent brain surgery to treat epilepsy. Recording electrical activity from human pyramidal cells in the CA3 area suggested that about 10 synapses existed for every 800 cell pairs tested. In mice, that concentration roughly tripled. Despite the relatively scant nerve cell connections in humans, those cells showed steady and robust activity when sending signals to one another — unlike mouse pyramidal cells. © Society for Science & the Public 2000–2025

Keyword: Learning & Memory
Link ID: 29616 - Posted: 01.08.2025

By Traci Watson New clues have emerged in the mystery of how the brain avoids ‘catastrophic forgetting’ — the distortion and overwriting of previously established memories when new ones are created. A research team has found that, at least in mice, the brain processes new and old memories in separate phases of sleep, which might prevent mixing between the two. Assuming that the finding is confirmed in other animals, “I put all my money that this segregation will also occur in humans”, says György Buzsáki, a systems neuroscientist at New York University in New York City. That’s because memory is an evolutionarily ancient system, says Buzsáki, who was not part of the research team but once supervised the work of some of its members. The work was published on Wednesday in Nature1. Scientists have long known that, during sleep, the brain ‘replays’ recent experiences: the same neurons involved in an experience fire in the same order. This mechanism helps to solidify the experience as a memory and prepare it for long-term storage. To study brain function during sleep, the research team exploited a quirk of mice: their eyes are partially open during some stages of slumber. The team monitored one eye in each mouse as it slept. During a deep phase of sleep, the researchers observed the pupils shrink and then return to their original, larger size repeatedly, with each cycle lasting roughly one minute. Neuron recordings showed that most of the brain’s replay of experiences took place when the animals’ pupils were small. That led the scientists to wonder whether pupil size and memory processing are linked. To find out, they enlisted a technique called optogenetics, which uses light to either trigger or suppress the electrical activity of genetically engineered neurons in the brain. First, they trained engineered mice to find a sweet treat hidden on a platform. Immediately after these lessons, as the mice slept, the authors used optogenetics to reduce bursts of neuronal firing that have been linked to replay. They did so during both the small-pupil and large-pupil stages of sleep. © 2025 Springer Nature Limited

Keyword: Learning & Memory; Sleep
Link ID: 29615 - Posted: 01.04.2025

By Ellen Barry Kevin Lopez had just stepped out of his house, on his way to meet his girlfriend for Chinese food, when it happened: He began to hallucinate. It was just a flicker, really. He saw a leaf fall, or the shadow of a leaf, and thought it was the figure of a person running. For a moment, on a clear night last month, this fast-moving darkness seemed to hurtle in his direction and a current of fear ran through him. He climbed into the car, and the door shut and latched behind him with a reassuring thunk. “It’s nothing,” he said. “I don’t know why — I think there’s a person there.” Light had always caused problems for Kevin when symptoms of schizophrenia came on. He thought that the lights were watching him, like an eye or a camera, or that on the other side of the light, something menacing was crouched, ready to attack. But over time, he had found ways to manage these episodes; they passed, like a leg cramp or a migraine. That night, he focused on things that he knew were real, like the vinyl of the car seat and the chill of the winter air. He was dressed for a night out, with fat gemstones in his ears, and had taken a break from his graduate coursework in computer science at Boston University. A “big bearish, handsome nerd” is the way he styled himself at 24. For the past four years, Kevin has been part of a living experiment. Shortly after he began hallucinating, during his junior year at Syracuse University, his doctors recommended him for an intensive, government-funded program called OnTrackNY. It provided him with therapy, family counseling, vocational and educational assistance, medication management and a 24-hour hotline. © 2025 The New York Times Company

Keyword: Schizophrenia; Stress
Link ID: 29614 - Posted: 01.04.2025

Nicola Davis Science correspondent Standing patiently on a small fluffy rug, Calisto the flat-coated retriever is being fitted with some hi-tech headwear. But this is not a new craze in canine fashion: she is about to have her brainwaves recorded. Calisto is one of about 40 pet dogs – from newfoundlands to Tibetan terriers – taking part in a study to explore whether their brainwaves synchronise with those of their owners when the pair interact, a phenomenon previously seen when two humans engage with each other. The researchers behind the work say such synchronisation would suggest person and pet are paying attention to the same things, and in certain circumstances interpreting moments in a similar way. In other words, owner and dog really are on the same wavelength. Dr Valdas Noreika of Queen Mary, University of London said he got the idea for the study after working on similar experiments with mothers and their babies, where such synchronisation has also been seen. “Owners modulate their language in a similar way as parents modulate when they speak to children,” he said. “There are lots of similarities. That could be one of the reasons why we get so attached to dogs – because we already have these cognitive functions and capacities to attach with someone who is smaller or requires help or attention.” Hints of an emotional bond between humans and their dogs stretch into the distant past: researchers have previously discovered the 14,000-year-old remains of a puppy buried in Germany alongside a man and a woman: the analysis suggested the young dog had been nursed through several periods of illness, despite having no particular use. © 2025 Guardian News & Media Limited o

Keyword: Brain imaging; Attention
Link ID: 29613 - Posted: 01.04.2025

By Roni Caryn Rabin Alcohol is a leading preventable cause of cancer, and alcoholic beverages should carry a warning label as packs of cigarettes do, the U.S. surgeon general said on Friday. It is the latest salvo in a fierce debate about the risks and benefits of moderate drinking as the influential U.S. Dietary Guidelines for Americans are about to be updated. For decades, moderate drinking was said to help prevent heart attacks and strokes. That perception has been embedded in the dietary advice given to Americans. But growing research has linked drinking, sometimes even within the recommended limits, to various types of cancer. Labels currently affixed to bottles and cans of alcoholic beverages warn about drinking while pregnant or before driving and operating other machinery, and about general “health risks.” But alcohol directly contributes to 100,000 cancer cases and 20,000 related deaths each year, the surgeon general, Dr. Vivek Murthy, said. He called for updating the labels to include a heightened risk of breast cancer, colon cancer and at least five other malignancies now linked by scientific studies to alcohol consumption. “Many people out there assume that as long as they’re drinking at the limits or below the limits of current guidelines of one a day for women and two for men, that there is no risk to their health or well-being,” Dr. Murthy said in an interview. “The data does not bear that out for cancer risk.” Only Congress can mandate new warning labels of the sort Dr. Murthy recommended, and it’s not clear that the incoming administration would support the change. © 2025 The New York Times Company

Keyword: Drug Abuse
Link ID: 29612 - Posted: 01.04.2025

By Carl Zimmer In our digital age, few things are more irritating than a slow internet connection. Your web browser starts to lag. On video calls, the faces of your friends turn to frozen masks. When the flow of information dries up, it can feel as if we are cut off from the world. Engineers measure this flow in bits per second. Streaming a high-definition video takes about 25 million bps. The download rate in a typical American home is about 262 million bps. Now researchers have estimated the speed of information flow in the human brain: just 10 bps. They titled their study, published this month in the journal Neuron, “The unbearable slowness of being.” “It’s a bit of a counterweight to the endless hyperbole about how incredibly complex and powerful the human brain is,” said Markus Meister, a neuroscientist at the California Institute of Technology and an author of the study. “If you actually try to put numbers to it, we are incredibly slow.” Dr. Meister got the idea for the study while teaching an introductory neuroscience class. He wanted to give his students some basic numbers about the brain. But no one had pinned down the rate at which information flows through the nervous system. Dr. Meister realized that he could estimate that flow by looking at how quickly people carry out certain tasks. To type, for example, we look at a word, recognize each letter and then sort out the sequence of keys to press. As we type, information flows into our eyes, through our brains and into the muscles of our fingers. The higher the flow rate, the faster we can type. In 2018, a team of researchers in Finland analyzed 136 million keystrokes made by 168,000 volunteers. They found that, on average, people typed 51 words a minute. A small fraction typed 120 words a minute or more. Dr. Meister and his graduate student, Jieyu Zheng, used a branch of mathematics known as information theory to estimate the flow of information required to type. At 120 words a minute, the flow is only 10 bits a second. © 2024 The New York Times Company

Keyword: Attention
Link ID: 29611 - Posted: 12.28.2024