By Brandon Keim Should you meet a turtle basking on a log in the sun, you might reasonably conclude that the turtle is in a good mood. Granted, there has been little scientific evidence that reptiles experience such emotional richness — until now, at least. Researchers in England identified what they describe as “mood states” — emotional experiences that are more than momentary — in red-footed tortoises by administering cleverly designed tests that use responses to ambiguity as windows into the psyche. The results of the study, published in the journal Animal Cognition in June, could apply to many more reptiles and have profound implications for how people treat them. “There was an acceptance that reptiles could do these short-term emotions,” said Oliver Burman, who studies animal behavior at the University of Lincoln in England and is an author of the paper. “They could respond to positive things and unpleasant things. But the long-term mood states are really important.” As for why it took so long to show this in reptiles, Dr. Burman said, “maybe we just haven’t asked them correctly.” Reptiles have a longstanding reputation as being unintelligent. Writing in 1892, Charles Henry Turner, the pioneering comparative psychologist, described reptiles as “intellectual dwarfs.” Eight decades later, in 1973, prominent scientists were referring to them as “reflex machines” and (in a paper titled “The Evolutionary Advantages of Being Stupid”) as possessing “a very small brain which does not function vigorously. Dr. Burman is among the scientists responsible for what some have called a “reptilian renaissance.” An array of findings — tortoises learning from one another, snakes with social networks, crocodiles displaying complex communication — indicate that reptiles are no less brainy than mammals and birds. © 2025 The New York Times Company

Keyword: Emotions; Evolution
Link ID: 29938 - Posted: 09.20.2025

By Sara Kiley Watson Humans started brewing alcohol for consumption thousands of years ago, and researchers have suggested that our ability to break down booze in our bodies has evolutionary roots dating back millions of years. Alcohol, known to scientists as ethanol, occurs naturally throughout nature, when microbes like bacteria and yeast break down sugars. This process of fermentation, harnessed by humans since ancient times, has given us the gifts of cheese, pickles, and wine, among other delights.* Nautilus Members enjoy an ad-free experience. Log in or Join now . But humans are far from the only creatures that imbibe—aye ayes, a species of lemur, will seek out nectar with a higher alcohol content, and spider monkey urine has been found to contain secondary metabolites of alcohol. Wild chimps, with whom humans share over 95 percent of our DNA, were caught on film snacking on fermenting fruit with their buddies earlier this year. Now, for the first time, researchers have discovered just how much alcohol some chimps are getting out of their fermented fruit snacks. In a new paper published in Science Advances, a team of scientists from the United States and the Ivory Coast reported that, in the course of a day, the wild chimps in their study consumed about 14 grams of pure ethanol. That’s about the equivalent, adjusting for body mass, of a human imbibing more than one standard drink a day, says University of California, Berkeley graduate student and study author Aleksey Maro. “We can say, pretty officially, that animals are chronically ingesting ethanol, especially our chimpanzee relatives,” Maro says. Maro and his colleagues made their discovery by following around wild chimps at two national parks in Africa—Kibale in Uganda and Taï in Ivory Coast—and scooping up test samples of 20 species of ripe fruits that the chimps typically like to eat. What they found is that these fruits have an average alcohol content of around 0.26 percent by weight. That might not sound like much, but primatologists at these locations estimate that chimps eat a whopping 10 pounds—or some 7 to 14 percent of their body weight—of fruit a day. The apes tended to prefer a fig called the Ficus mucuso at Kibale and the plum-esque fruit from Parinari excelsa trees at Taï. These treats were among the fruits with the highest alcohol content. © 2025 NautilusNext Inc.,

Keyword: Drug Abuse; Evolution
Link ID: 29937 - Posted: 09.20.2025

By Calli McMurray Studying animal behavior in the wild often gets hairy, with little experimental control and an abundance of extraneous data. And when multiple animals get together, the way they look, act and smell all influence one another, making it difficult to parse complex social interactions, says Andres Bendesky, associate professor of ecology, evolution and environmental biology at Columbia University. Robotic or animated partners, however, can simplify that equation. Studying animal-robot interaction gives researchers complete control over one partner during any tête-à-tête, Bendesky says. It makes it possible to present the same stimulus to an animal repeatedly or compare how different individuals react. And the method complements observation-based research: Scientists can use a robot- or animation-based paradigm to test ideas gleaned from studies that use artificial-intelligence tools to track behavior. Bendesky is part of a growing cohort of neuroscientists turning to robots to help them decode social interactions. The quirks are still being ironed out, but the approach is already helping several groups tackle questions about schooling, fighting and chatting behaviors. The rigor of the results depends on whether a critter believes what it sees, says Tim Landgraf, professor of artificial and collective intelligence at Freie Universität Berlin, who uses robots to study group behavior in guppies. That can be hard to gauge; there’s no handbook that describes what traits make a robot believable, he says. But researchers can compare how animals act toward a real peer versus a counterfeit one, says Steve Chang, associate professor of psychology and neuroscience at Yale University, who doesn’t work with robots but studies the social behavior of macaques and marmosets. © 2025 Simons Foundation

Keyword: Robotics; Sexual Behavior
Link ID: 29936 - Posted: 09.20.2025

By Catherine Offord As the National Football League’s (NFL’s) latest season gets underway, so, too, does the conversation about the risk of serious brain damage to its athletes. Multiple well-publicized studies in recent years have linked repetitive head impacts typical in football and other contact sports to an increased likelihood of chronic traumatic encephalopathy (CTE), a neurodegenerative condition characterized by a buildup of misfolded proteins in the brain. Now, a leading CTE research group reports evidence that regular sports-related impacts could cause brain damage before the condition’s hallmark features appear. An analysis of postmortem brain tissue from athletes and nonathletes who died before their early 50s, published today in Nature, identifies multiple cellular differences between the groups, regardless of whether CTE was present. The findings support the idea that contact sports are associated with specific cellular changes in the brain. The study also “helps us understand, or at least ask new questions about, the mechanisms that bridge that acute exposure to later neurodegeneration,” says Gil Rabinovici, a neurologist and researcher at the University of California San Francisco who was not involved in the work. But not many brains were examined—fewer than 30 for most analyses. And the study doesn’t show that the neuron loss and other brain changes affect a person’s cognitive or mental health, cautions Colin Smith, a neuropathologist at the University of Edinburgh. “What does this mean clinically? … That is still the big question hanging here.” CTE recently hit the headlines again after a shooter killed four people and himself in the New York City building housing NFL’s headquarters this summer. In a note found by police, the former high school football player reportedly said he thought he had CTE, and asked that his brain be studied.

Keyword: Brain Injury/Concussion
Link ID: 29935 - Posted: 09.20.2025

Chris Simms A wearable device could make saying ‘Alexa, what time is it?’ aloud a thing of the past. An artificial intelligence (AI) neural interface called AlterEgo promises to allow users to silently communicate just by internally articulating words. Sitting over the ear, the device facilitates daily life through live communication with the Internet. “It gives you the power of telepathy but only for the thoughts you want to share,” says AlterEgo’s chief executive Arnav Kapur, based in Cambridge, Massachusetts. Kapur unveiled the device on 8 September. The device does not read brain activity, but predicts what a wearer wants to say from signals in muscles used to speak, then sends audio information back into their ear. The researchers say that their non-invasive technology could help people with motor neuron disease (amyotrophic lateral sclerosis; ALS) and multiple sclerosis (MS) who have trouble speaking, but also want to make the devices commercially available for general use. In a promotional video on the AlterEgo website, Kapur says that “it’s a revolutionary breakthrough with the potential to change the way we interact with our technology, with one another and with the world around us”. “The big question about this is ‘how likely is that potential to be realized?,” says Howard Chizeck, an electrical and computer engineer at the University of Washington in Seattle. Chizeck says that the technology seems workable and is less of a privacy risk than listening devices such as Amazon’s Alexa are, but isn’t convinced that the device will catch on for commercial use. © 2025 Springer Nature Limited

Keyword: Robotics; Language
Link ID: 29934 - Posted: 09.20.2025

By Meghan Rosen Maybe you’ve seen an influencer make French fries out of almond flour. Or a sandwich recipe that swaps bread for fried cheese. They’re called keto meals, and they’re largely shared for one reason: to help people lose weight. In the ketogenic diet, fat is king, and carbs are public enemy number one. Going keto means restricting carbs to the bare minimum and replacing those lost calories with fat. It’s the antithesis of the low-fat diet craze of the 1990s. Losing fat on keto diets typically means eating fat — and lots of it. The idea may sound paradoxical. But without our typical go-to energy source (sugar), our bodies learn to rely on a different type of fuel. In keto dieters, the liver converts fat into molecules called ketone bodies, which the body can burn instead of sugar. That can lead to weight loss, despite an unusually high intake of fat. Such results may explain why so many Americans have tried the keto diet on for size. “I think a lot of people look at a ketogenic diet and think, ‘I’ll lose weight, I’ll be healthier,’” says Molly Gallop, a physiologist at Earlham College in Richmond, Ind. On the surface, they may be right. But staying on the diet long-term could carry some risks, a new study in mice suggests. Mice fed a ketogenic diet for up to about a year — decades in human time — experienced health problems including glucose intolerance and signs of liver and cardiovascular disease, Gallop and her colleagues report September 19 in Science Advances. The work uncovers some potential hidden costs to going keto, says physiologist Amandine Chaix, at the University of Utah in Salt Lake City. “It’s a cautionary tale,” she says. People sticking to this high-fat plan need to be careful, she says, “because this is not a magical dietary approach.” © Society for Science & the Public 2000–2025.

Keyword: Obesity
Link ID: 29933 - Posted: 09.20.2025

By Sujata Gupta Anne-Laure Le Cunff was something of a wild child. As a teenager, she repeatedly disabled the school fire alarm to sneak smoke breaks and helped launch a magazine filled with her teachers’ fictional love lives. Later, as a young adult studying neuroscience, Le Cunff would spend hours researching complex topics but struggled to complete simple administrative tasks. And she often obsessed over random projects before abruptly abandoning them. Then, three years ago, a colleague asked Le Cunff if she might have attention-deficit/hyperactivity disorder, or ADHD, a condition marked by distractibility, hyperactivity and impulsivity. Doctors confirmed her colleague’s suspicions. But fearing professional stigma, Le Cunff — by then by then a postdoctoral fellow in the ADHD Lab at King’s College London — kept her diagnosis secret until this year. Le Cunff knew all too well about the deficits associated with ADHD. But her research — and personal experience — hinted at an underappreciated upside. “I started seeing … breadcrumbs pointing at a potential association between curiosity and ADHD,” she says. People within the ADHD community have long recognized that the condition can be both harmful and helpful. Researchers, though, have largely focused on the harms. And those studying treatments tend to define success as a reduction in ADHD symptoms, with little regard to possible benefits. That’s starting to change. For instance, Norwegian researchers asked 50 individuals with ADHD to describe their positive experiences with the disorder as part of an effort to develop more holistic treatments. People cited their creativity, energy, adaptability, resilience and curiosity, researchers reported in BMJ Open in October 2023. © Society for Science & the Public 2000–2025.

Keyword: ADHD; Attention
Link ID: 29932 - Posted: 09.17.2025

Rachel Fieldhouse Deep in the rainforests of the Democratic Republic of the Congo, Mélissa Berthet found bonobos doing something thought to be uniquely human. During the six months that Berthet observed the primates, they combined calls in several ways to make complex phrases1. In one example, bonobos (Pan paniscus) that were building nests together added a yelp, meaning ‘let’s do this’, to a grunt that says ‘look at me’. “It’s really a way to say: ‘Look at what I’m doing, and let’s do this all together’,” says Berthet, who studies primates and linguistics at the University of Rennes, France. In another case, a peep that means ‘I would like to do this’ was followed by a whistle signalling ‘let’s stay together’. The bonobos combine the two calls in sensitive social contexts, says Berthet. “I think it’s to bring peace.” The study, reported in April, is one of several examples from the past few years that highlight just how sophisticated vocal communication in non-human animals can be. In some species of primate, whale2 and bird, researchers have identified features and patterns of vocalization that have long been considered defining characteristics of human language. These results challenge ideas about what makes human language special — and even how ‘language’ should be defined. Perhaps unsurprisingly, many scientists turn to artificial intelligence (AI) tools to speed up the detection and interpretation of animal sounds, and to probe aspects of communication that human listeners might miss. “It’s doing something that just wasn’t possible through traditional means,” says David Robinson, an AI researcher at the Earth Species Project, a non-profit organization based in Berkeley, California, that is developing AI systems to decode communication across the animal kingdom. As the research advances, there is increasing interest in using AI tools not only to listen in on animal speech, but also to potentially talk back. © 2025 Springer Nature Limited

Keyword: Animal Communication; Language
Link ID: 29931 - Posted: 09.17.2025

Andrew Gregory Health editor A daily pill for weight loss can help people reduce their body weight by as much as a fifth, according to a trial that could pave the way for millions more people to shed pounds. The drug, called orforglipron, is manufactured by Eli Lilly and targets the same GLP-1 receptors as weight loss injections such as Mounjaro and Wegovy. In a trial of 3,127 adults, one in five people who took the once-a-day tablet for 72 weeks lost 20% or more of their body weight. Weight loss jabs have been transformative but pill versions are seen as a holy grail because they are easier to store, distribute and administer and are also expected to be cheaper, offering fresh hope for the millions of people trying to lose weight. Orforglipron is a GLP-1 agonist, a type of medication that helps lower blood sugar levels, slows the digestion of food and can reduce appetite. The weight loss seen among people taking the tablet is not as stark as that among patients taking tirzepatide (Mounjaro), which is also made by Eli Lilly, but experts believe the tablet will be more accessible and convenient compared with injections. Orforglipron is not yet approved by the US Food and Drug Administration (FDA) or regulators in other countries. Eli Lilly has said it expects substantial demand when the new pill is launched. The company published a snapshot of the results in August and the full paper detailing the findings has now been published in the New England Journal of Medicine and presented to the annual meeting of the European Association for the Study of Diabetes in Vienna, Austria. © 2025 Guardian News & Media Limited

Keyword: Obesity
Link ID: 29930 - Posted: 09.17.2025

Nic Fleming In the early 2000s, Brazilian nutrition researcher Carlos Monteiro made a puzzling discovery that led to an epiphany. While trawling survey data on household spending to try to understand why rates of obesity and type 2 diabetes were rising so rapidly in his home country, he was surprised to note that people were buying smaller quantities of sugar, salt and other ingredients generally associated with these conditions than they had in previous decades. Only when Monteiro and his colleagues dug deeper did they find the culprit. People were buying less sugar to prepare cakes and desserts, but eating more of it in pre-made pastries and breakfast cereal. They were buying less salt, but consuming more of it in frozen pizzas, chicken nuggets and dehydrated packet soups. “We realized the problem was our traditional dietary patterns were being replaced by foods that are processed so many times that they can no longer be recognized in the final products. We called them ultra-processed foods.” Monteiro, a nutrition and public-health researcher at the University of São Paulo, first used the term ultra-processed food (UPF) in a paper in 2009, arguing that people interested in promoting healthy diets should focus more on the degree, extent and purpose of processing than on nutrient profiles1. It was a radical idea that caught the attention of other researchers, who, over the next decade or so, published dozens of papers linking UPFs with obesity and a range of other health problems. Governments took notice, too. In 2014, Brazil began advising people to avoid UPFs. Other countries, including France, Belgium and Israel, followed suit. Robert F. Kennedy Jr, secretary of the US Department of Health and Human Services (HHS), has been a critic of UPFs, saying in January that they are “poisoning the American people”. In May, the US government announced plans for a research agenda to support nutrition policy and improve people’s diets, in part by improving understanding of the impacts of UPFs on health. © 2025 Springer Nature Limited

Keyword: Obesity
Link ID: 29929 - Posted: 09.17.2025

By Claudia López Lloreda Mouse pups, like other infants across the animal kingdom, cry to get their mother’s attention. The oxytocin system drives this communication and shapes how baby mice interact when reunited with their mothers, according to a study out today in Science. Oxytocin, known colloquially as the “love” or “cuddle” hormone, stimulates milk release during nursing and promotes maternal care behaviors. But most oxytocin research thus far has focused solely on the mother, overlooking the neuropeptide’s potential effects on an infant’s brain and behavior. This new study shows “the other half of the equation to what we already knew,” says Zoe Donaldson, associate professor of behavioral neuroscience at the University of Colorado Boulder, who was not involved with the study. Oxytocin is “this social signal that ultimately reinforces relationships,” she says. The work employed a novel optogenetic tool that enabled the team to turn off neurons deep in the hypothalamus of mouse pups. After being separated from their mothers for three hours, the pups vocalized more using distinct patterns when reunited with their mothers than did pups that had not been separated, a process controlled by oxytocin neurons in the pups’ hypothalamus, the team found. “It would make sense if oxytocin is on both sides of this: making moms want to take care of their pups that are calling, and making pups call in a manner that makes mom want to take care of them,” Donaldson says. “Then we have this sort of convergence where oxytocin is once again doing everything.” © 2025 Simons Foundation

Keyword: Sexual Behavior; Animal Communication
Link ID: 29928 - Posted: 09.13.2025

By Andrea Thompson A school-aged child in Los Angeles County has died from a rare but always fatal complication from a measles infection they acquired when they were an infant who was too young to be vaccinated. The first dose of the vaccine is typically not administered until one year of age. Experts say the death underscores the need for high levels of vaccination in a population to protect the most vulnerable against the disease, as well as from side effects that can occur long after the initial illness has passed. “This case is a painful reminder of how dangerous measles can be, especially for our most vulnerable community members,” said Los Angeles County Health Officer Muntu Davis in a recent statement. The child who died suffered from subacute sclerosing panencephalitis (SSPE), a progressive brain disorder that usually develops two to 10 years after a measles infection. The measles virus appears to mutate into a form that avoids detection by the immune system, allowing it to hide in the brain and eventually destroy neurons. “It’s just a virus that goes unchecked and destroys brain tissue, and we have no therapy for it,” said Walter Orenstein, an epidemiologist and professor emeritus at Emory University, to Scientific American earlier this year. People with SSPE experience a gradual, worsening loss of neurological function and usually die within one to three years after diagnosis, according to the Los Angeles County Health Department. The disorder affects only about one in every 10,000 people who contract measles. But the risk may be as high as about one in 600 for those who are infected as infants. “There is no treatment for this. Children who suffer from this will always die,” said Paul Offit, director of the Vaccine Education Center and an attending physician in the Division of Infectious Diseases at Children’s Hospital of Philadelphia, in a previous interview with Scientific American. © 2025 SCIENTIFIC AMERICAN,

Keyword: Development of the Brain
Link ID: 29927 - Posted: 09.13.2025

By Jake Buehler All eight arms of an octopus can be used for whatever their cephalopod owner wishes, but some arms are favored for certain tasks. A new, detailed analysis of how octopuses wield their famously flexible appendages suggests that all eight arms share a skill set, but the front four spend more time on exploration and the back four on movement. The findings, published September 11 in Scientific Reports, provide a comprehensive accounting of how subtle arm movements coordinate the clever invertebrates’ repertoire of behaviors. Octopuses live their lives through their sucker-lined arms, which make up the bulk of their body mass and contain most of their nervous system. Marine biologist Chelsea Bennice wanted to understand how octopuses use the extreme flexibility of their boneless limbs to move, hunt and investigate their environment. Her colleagues had examined some of these behaviors in laboratory settings, but not in the wild. Bennice and her colleagues watched 25 videos, filmed from 2007 to 2015, of multiple species of wild octopuses in Spain and the Caribbean, cataloging their behaviors and arm movements. In all, the researchers logged nearly 4,000 arm actions, which could be broken down into 12 types, including raising, reaching and grasping. The arms could deform in four distinct ways: elongating, shortening, bending and twisting. The team found that the octopuses were exceptionally ambidextrous. “Octopuses are ultimate multitaskers,” says Bennice, of Florida Atlantic University in Boca Raton. “All arms are capable of all arm behaviors and all arm deformations. They can even use multiple arm actions on a single arm and on several arms at the same time.” © Society for Science & the Public 2000–2025.

Keyword: Laterality; Evolution
Link ID: 29926 - Posted: 09.13.2025

By Kenneth Chang After decades of brain research, scientists still aren’t sure whether most people see the same way, more or less — especially with colors. Is what I call red also red for you? Or could my red be your blue? Or maybe neon pink? If it were possible to project what I see directly into your mind, would the view be the same, or would it instead resemble a crazy-hued Andy Warhol painting? “That’s an age-old question, isn’t it?” said Andreas Bartels, a professor of visual neuroscience at the University of Tübingen in Germany. But scientists do have a good understanding of which parts of the brain handle vision. They have even figured out where various vision-processing tasks are performed, like recognizing what is moving, identifying colors and adjusting to different lighting conditions. Amazingly, it is even possible to deduce what you’re seeing by looking at an M.R.I. scan showing which parts of your brain are lighting up. “That comes out of the world of science fiction, or one would think, right?” Dr. Bartels said. “It’s amazing that this is possible, but this always has happened in individual brains.” That is, researchers pulled off this sleight of science with individuals. They would first show a subject lying in the M.R.I. machine a series of images, mapping out how that person’s brain responded. After that initial training, the researchers could randomly show one of the images and, based on just the brain activity, make a good guess at what the image was. In new research, Dr. Bartels and Michael Bannert, a postdoctoral researcher in Dr. Bartels’ laboratory, used that technique to provide a partial answer to the question of whether most of us have a shared sense of colors. They put 15 people, all with standard color vision, in an M.R.I. machine. The volunteers viewed expanding concentric rings that were red, green or yellow. © 2025 The New York Times Company

Keyword: Vision; Consciousness
Link ID: 29925 - Posted: 09.10.2025

Ian Sample Science editor The cry of a distressed baby triggers a rapid emotional response in both men and women that is enough to make them physically hotter, researchers say. Thermal imaging revealed that people experienced a rush of blood to the face that raised the temperature of their skin when they were played recordings of babies wailing. The effect was stronger and more synchronised when babies were more distressed, leading them to produce more chaotic and disharmonious cries. The work suggests that humans respond automatically to specific features in cries that ramp up when babies are in pain. “The emotional response to cries depends on their ‘acoustic roughness’,” said Prof Nicolas Mathevon at the University of Saint-Etienne in France. “We are emotionally sensitive to the acoustic parameters that encode the level of pain in a baby’s cry.” Evolution equipped baby humans with a hard-to-ignore wail to boost their odds of getting the care they need. But not all infant cries are the same. When a baby is in real distress, they forcefully contract their rib cage, producing higher pressure air that causes chaotic vibrations in the vocal cords. This produces “acoustic roughness”, or more technically, disharmonious sounds called nonlinear phenomena (NLP). To see how men and women responded to infants’ cries, scientists played recordings to volunteers with little or no experience with babies. While listening, the participants were filmed with a thermal camera that captured subtle changes in their facial temperature. © 2025 Guardian News & Media Limited

Keyword: Sexual Behavior; Emotions
Link ID: 29924 - Posted: 09.10.2025

By Viviane Callier All animals, from jellyfish to humans, need sleep. But how these wide-ranging organisms control that need has remained a mystery. It turns out that—in fruit flies, at least—sleep might be an “inescapable consequence” of aerobic metabolism, according to a new study. Mitochondria in Drosophila’s sleep-regulating neurons sense metabolic damage that accumulates during waking hours and trigger the pressure to sleep. “It’s a really beautiful contribution,” says Keith Hengen, associate professor of biology at Washington University in St. Louis, who was not involved in the work. The study explains how the brain integrates information from a metabolic thermostat to regulate sleep pressure, Hengen says. “That’s a really hard problem, and I think they’ve nailed it.” The regulators of sleep are distinct from the function of sleep, Hengen and other sleep researchers note. Just as fullness regulates food intake, but food intake doesn’t so much serve to fill the stomach as to get calories and nutrients, “we need to make this distinction between sensing of sleep pressure and the function of sleep,” says Giorgio Gilestro, associate professor of systems neurobiology at Imperial College London, who was not involved in the new study. And with respect to sleep pressure, he adds, there are two processes at play: a well-studied circadian clock mechanism that links sleep to daylight cycles, and a less-understood homeostatic process that fine-tunes the need for sleep based on other factors. © 2025 Simons Foundation

Keyword: Sleep; Evolution
Link ID: 29923 - Posted: 09.10.2025

By Sofia Caetano Avritzer When Canada legalized cannabis in 2018, its effects on human health were all over the news. Cyntia Duval, a women’s health researcher at the University of Toronto at the time, wondered how its consumption might affect female fertility. To her surprise, there was almost no information on the subject — though there was plenty of data on marijuana’s effects on pregnancy and male fertility. Chemicals in cannabis may push eggs to become ready for fertilization. But this may come at a cost: more eggs with the wrong number of chromosomes, Duval and colleagues now report in a study published September 9 in Nature Communications. Delta-9-tetrahydrocannabinol, or THC, is the main psychoactive chemical in marijuana. It binds to cannabinoid receptors in the brain. But these receptors are all over our bodies, including in our reproductive organs. The receptors usually bind endocannabinoids, molecules naturally produced by the body and essential for normal bodily functions like the production of eggs and sperm. Consuming THC can affect cannabinoid receptors in the reproductive system. Many studies report that using cannabis decreases sperm count and motility. Men are usually told to avoid cannabis for at least three months before trying to conceive, Duval says. But what about women? © Society for Science & the Public 2000–2025.

Keyword: Drug Abuse; Sexual Behavior
Link ID: 29922 - Posted: 09.10.2025

By Rachel E. Gross The first thing Debra McVean did when she woke up at the hospital in March 2024 was try to get to the bathroom. But her left arm wouldn’t move; neither would her left leg. She was paralyzed all along her left side. She had suffered a stroke, her doctor soon explained. A few nights before, a blood clot had lodged in an artery in her neck, choking off oxygen to her brain cells. Now an M.R.I. showed a dark spot in her brain, an eerie absence directly behind her right eye. What that meant for her prognosis, however, the doctor couldn’t say. “Something’s missing there, but you don’t know what,” Ms. McVean’s husband, Ian, recalled recently. “And you don’t know how that will affect her recovery. It’s that uncertainty, it eats away at you.” With a brain injury, unlike a broken bone, there is no clear road to recovery. Nor are there medical tools or therapies to help guide the brain toward healing. All doctors can do is encourage patients to work hard in rehab, and hope. That is why, for decades, the medical attitude toward survivors of brain injury has been largely one of neurological “nihilism,” said Dr. Fernando Testai, a neurologist at the University of Illinois, Chicago, and the editor in chief of the Journal of Stroke and Cerebrovascular Diseases. Stroke, he said, “was often seen as a disease of ‘diagnose and adios.’” That may be about to change. A few days after Ms. McVean woke up in the Foothills Medical Center in Calgary, she was told about a clinical trial for a pill that could help the brain recover from a stroke or traumatic injury, called Maraviroc. Given her level of physical disability, she was a good candidate for the study. She hesitated. The pills were large — horse pills, she called them. But she knew the study could help others, and there was a 50 percent chance that she would get a drug that could help her, too. © 2025 The New York Times Company

Keyword: Stroke; Regeneration
Link ID: 29921 - Posted: 09.06.2025

Rachel Fieldhouse An analysis of 56 million people has shown that exposure to air pollution increases the risk of developing a particular form of dementia, the third most common type after Alzheimer’s disease and vascular dementia. The study, published in Science on 4 September1, suggests that there is a clear link between long-term exposure to PM2.5 — airborne particles that are smaller than 2.5 micrometres in diameter — and the development of dementia in people with Lewy body dementia or Parkinson’s disease. The study found that PM2.5 exposure does not necessarily induce Lewy body dementia, but “accelerates the development,” in people who are already genetically predisposed to it, says Hui Chen, a clinician–neuroscientist at the University of Technology Sydney in Australia. PM2.5 exposure Lewy body dementia is an umbrella term for two different types of dementia: Parkinson’s disease with dementia, and dementia with Lewy bodies. In both cases, dementia is caused by the build-up of α-synuclein (αSyn) proteins into clumps, called Lewy bodies, in the brain’s nerve cells, which cause the cells to stop working and eventually die. Studies have suggested that long-term exposure to air pollution from car-exhaust, wildfires and factory fumes, is linked with increased risks of developing neurodegenerative illnesses, including Parkinson's disease with dementia2. Study co-author Xiaobo Mao, who researches neurodegenerative conditions at Johns Hopkins University in Baltimore, Maryland, says he and his colleagues wanted to determine if PM2.5 exposure also influenced the risk of developing Lewy body dementia. They analysed 2000–2014 hospital-admissions data from 56.5 million people with Lewy body dementia and Parkinson’s disease with or without dementia. The data served to identify people with severe neurological diseases. © 2025 Springer Nature Limited

Keyword: Alzheimers; Parkinsons
Link ID: 29920 - Posted: 09.06.2025

Ivana Drobnjak O'Brien An ultrasound “helmet” offers potential new ways for treating neurological conditions without surgery or other invasive procedures, a study has shown. The device can target brain regions 1,000 times smaller than ultrasound can, and could replace existing approaches such as deep brain stimulation (DBS) in treating Parkinson’s disease. It also holds potential for conditions such as depression, Tourette syndrome, chronic pain, Alzheimer’s and addiction. Unlike DBS, which requires a highly invasive procedure in which electrodes are implanted deep in the brain to deliver electrical pulses, using ultrasound sends mechanical pulses into the brain. But no one had managed to create an approach capable of delivering them precisely enough to make a meaningful impact until now. A study published in Nature Communications introduces a breakthrough system that can hit brain regions 30 times smaller than previous deep-brain ultrasound devices could. “It is a head helmet with 256 sources that fits inside an MRI scanner,” said the author and participant Ioana Grigoras, of Oxford University. “It is chunky and claustrophobic putting it on the head at first, but then you get comfortable.” Current DBS methods used on Parkinson’s patients use hard metal frames that are screwed into the head to hold them down. To test the system, the researchers applied it to seven volunteers, directing ultrasound waves to a tiny region the size of a grain of rice in the lateral geniculate nucleus (LGN), the key pathway for visual information that comes from the eyes to the brain. “The waves reached their target with remarkable accuracy,” the senior author Prof Charlotte Stagg of Oxford University said. “That alone was extraordinary, and no one has done it before.” Follow-up experiments showed that modulating the LGN produced lasting effects in the visual cortex, reducing its activity. “The equivalent in patients with Parkinson’s would be targeting a motor control region and seeing tremors disappear,” she added. © 2025 Guardian News & Media Limite

Keyword: Parkinsons; Brain imaging
Link ID: 29919 - Posted: 09.06.2025