By Jennie Erin Smith A few years ago, scientists saw something surprising in the brain tissue of people who died with Alzheimer’s disease: white blood cells that multiply in response to foreign threats and are seldom seen inside healthy brains. Whether these so-called CD8+ killer T cells, which normally target infected cells in the body, were there to harm or help was unclear. An answer began to emerge in 2023, when a team led by neuroscientist David Holtzman showed that in mice bred to overexpress tau—a toxic protein that builds up in the neurons of people with Alzheimer’s and several other neurodegenerative diseases—getting rid of the T cells stemmed tissue loss and preserved the mice’s cognition, even as tau kept building up. Now, the same group has explored what prompts these cells to wreak havoc in the brain. In a mouse study published last week in Nature Neuroscience, Holtzman and immunology researcher Hao Hu, both at Washington University in St. Louis, report that immune cells in the lymph nodes of the neck instruct the T cells to clone themselves before they enter the brain. Without them, the mice had far fewer cloned T cells inside their brains and experienced less neurodegeneration. The study is “beautiful work,” says neuroscientist Kenneth Kosik of the University of California, Santa Barbara, who studies tau but was not involved in the research. It also suggests that existing drugs, developed for other conditions, might work in Alzheimer’s by shielding the brain from the destructive cells. The new study homes in on a type of dendritic cells, immune cells that, in effect, give the killer T cells their orders. After cutting up the invader’s proteins, the dendritic cells present the antigens as bite-size pieces that T cells can recognize. T cells with compatible receptors can then become activated, which causes the cells to start to clone themselves, attack cells bearing the antigen, and cause inflammation. © 2026 American Association for the Advancement of Science.

Keyword: Neuroimmunology; Alzheimers
Link ID: 30401 - Posted: 09.09.2026

By Emily Baumgaertner Nunn Are you naturally anxious? Highly adventurous? More argumentative than you’d like to admit? Those tendencies are often measured through what psychologists call the “Big Five” dimensions of personality: extroversion, agreeableness, conscientiousness, neuroticism and openness to experience. Each trait exists on a continuum and tends to remain fairly stable throughout adult life. But what determines where you land on those spectra? Scientists have long known that personality is influenced by a host of factors — including DNA. The challenge has been deciphering the specific pathways through which a genetic blueprint nudges the direction of a person’s life. To map this sprawling architecture, a group of experts formed a research consortium and analyzed more than one million genomes, searching for variants associated with personality. The researchers also compared the genes of thousands of siblings and parent-child pairs to rule out other factors that could be at play. With data from 46 different study cohorts, they found a symphony of 1,260 genetic markers tied to personality, nearly two-thirds of them identified for the first time. The findings, published on Wednesday in the journal Nature, reaffirmed scientists’ understanding that temperament and disposition are shaped not by a few particular genes, but by thousands of tiny variants that can be expressed in different circumstances. The sheer scale of the project also brought new statistical power to the study of personality genetics, giving researchers a tool kit to investigate the biological mechanisms behind how we think, feel and behave. “I view the 1,260 variants as kind of a testament to the fact that we’ve now got the power to answer all of these other questions that we couldn’t answer before,” said Elliot Tucker-Drob, a professor of psychology at the University of Texas at Austin and a leader of the study. © 2026 The New York Times Company

Keyword: Emotions; Genes & Behavior
Link ID: 30395 - Posted: 09.05.2026

By Meghan Rosen The mysterious pain disorder fibromyalgia may have some surprising genetic roots. An analysis of 2.5 million people suggests fibromyalgia is neurological in nature, scientists report July 28 in Nature Medicine. The genetics study is the latest — and largest — to try and get a grasp on a long-debated condition. The work establishes a biological basis for fibromyalgia, which was historically thought to be psychological. Evidence of the condition’s biological origins has been accumulating for years, says Michael Wainberg, a geneticist at the University of Toronto. “But now,” he says, “I think it’s absolutely indisputable.” Fibromyalgia is known for causing widespread pain and fatigue, though symptoms can look different among patients. They may also have anxiety, depression and sleep disruptions, says Jonathan Aebischer, a chronic pain researcher and clinician at Oregon Health & Science University in Portland who was not part of the new study. “I can’t say that I’ve ever seen two cases of fibromyalgia that are exactly alike,” he says. And though fibromyalgia has real, physical symptoms, they can appear to be invisible, says Kristal Kent, a patient advocate at the nonprofit organization Veteran Voices for Fibromyalgia, based in Cleveland. “One day, I can seem OK,” she says, “and the next day I could be crashed out in a flare-up.” For her, some of the biggest symptoms are chronic fatigue and brain fog. Fibromyalgia affects some 4 million adults in the United States, but the true number of people affected might be even higher, says Hanna Ollila, a genetic epidemiologist at the University of Helsinki. Besides the symptom variability, there are no blood tests to screen for fibromyalgia and it can be misdiagnosed as other diseases. © Society for Science & the Public 2000–2026.

Keyword: Genes & Behavior; Neuroimmunology
Link ID: 30394 - Posted: 09.05.2026

By Michele Patterson Ford When survivors of trauma recount their experiences, they are often questioned because of how they relay their stories. They may have problems remembering what happened, or their memories may be jumbled or even contradictory. People hearing those stories—attorneys, reporters, healthcare workers or friends—may expect a clearer, linear narrative. Those unaffected by trauma may also be surprised to hear how the person acted in the moment. It’s easy to assume that someone experiencing a traumatic event would have a “fight or flight” response, instinctively fighting off a perpetrator or fleeing the scene—but that might not be the case. Understanding the science of how trauma affects memory and behavior reveals why these responses can actually be expected and are not contradictory. In both my academic and clinical work as a psychologist, I have witnessed the impact trauma has on people’s memories and behaviors, especially when an event in their present life triggers something from their past. Research shows that taking a trauma-informed approach, which prioritizes understanding and curiosity about someone’s experience as opposed to judgment or critical evaluation, increases empathy for survivors’ thoughts, feelings and behaviors. According to the World Health Organization, approximately 70 percent of people worldwide report experiencing a traumatic event in their lifetime. The majority of these people do not develop PTSD, a clinical diagnosis of symptoms, such as having nightmares and flashbacks about the event, avoiding places that are reminders of it, and increased arousal that can make concentration and sleep difficult. Many survivors don’t meet criteria for PTSD but struggle with feeling distressed, depressed or anxious. © 2026 SCIENTIFIC AMERICAN INC.

Keyword: Learning & Memory; Stress
Link ID: 30383 - Posted: 08.22.2026

By Sarah Thau Sound the alarm! Activating a subset of neurons in the medulla promotes anxiety in mice, a study published in Neuron finds. Anxiety is typically thought of as a set of “complex, social, environmental, biological, neurobiological interactions” involving multiple regions across the brain, says Oliver Robinson, professor of neuroscience and mental health at University College London, who was not involved in this work. So he was “surprised that you can have such dramatic effects by just looking at a single cell type.” The role of medullary neurons in anxiety adds to a growing body of work on anxiety circuitry, says study investigator Carlos Fernández-Peña, assistant professor of neurological sciences at the University of Nebraska. “It was already complex. Now let’s add some more.” Two sets of neurons—C1 and A1—in the rostral ventrolateral medulla (RVLM) produce catecholamines that could drive anxiety, but only C1 neurons are activated when mice are stressed, Fernández-Peña says. The challenge, then, was to study only C1 neurons, which are intermingled with A1 neurons, in awake mice to uncover their role in anxiety-like behaviors, he says. He and his colleagues employed two different genetic recombination tools—one called INTRSECT and another called ConVERGD—for the first time, according to study investigator Lindsay Schwarz, associate member of the St. Jude Children’s Research Hospital faculty, who co-developed the latter tool. This pairing enabled them to make transgenic mice in which they could optogenetically modulate only the C1 neurons and not the A1 cells, using careful genetic logic. © 2026 Simons Foundation

Keyword: Emotions
Link ID: 30376 - Posted: 08.19.2026

Elie Dolgin The video opens with a man in his 80s slumped in a hospital bed, his face hollow as he scrunches his eyes. A jump cut advances the scene three days: the man is alert now, words gathering as he identifies his son. Six months later, he is pictured sitting upright, engaged in conversation. His gaze is animated. At eight months, the man walks briskly down a hospital corridor. He recites a near-century-old Maoist military anthem from memory. He is practically unrecognizable from the withered figure in the opening frame. The footage records the recovery of a man who, in September 2020, became the first person in the world to undergo a surgery known as deep cervical lymphatic-venous anastomosis (dcLVA) to treat Alzheimer’s disease. The procedure involves connecting tiny lymphatic vessels in the neck — part of the drainage system that carries waste away from the brain — to nearby veins, creating a route that, in theory, allows fluid and waste proteins to flow more easily into the bloodstream. The treatment was first reported1 in 2022 in a Chinese-language journal by microsurgeon Qingping Xie, president of the Qiushi Hospital in Hangzhou, China. At the time, it drew little notice. But that changed the following year, when Wei Chen, a lymphatic microsurgeon at the Cleveland Clinic in Ohio, began showing the footage (with consent from Xie and the man’s family) at surgical meetings around the world. “A lot of jaws dropped,” recalls Chen. “It basically started a frenzy of this surgery being performed left and right.” Almost all of the surgeries took place in China, where hundreds of hospitals were soon offering the experimental procedure. Propelled by viral testimonial videos and aggressive marketing campaigns on social-media platforms such as Douyin and WeChat, it was sought out by thousands — with many people paying more than 200,000 yuan (US$30,000) for a chance of recovery. © 2026 Springer Nature Limited

Keyword: Alzheimers
Link ID: 30370 - Posted: 08.12.2026

By Meghan Rosen Dogs may be even more attuned to people’s feelings than we think. Man’s best friend has a knack for knowing what humans are thinking, reading signs as subtle as jangling keys or a dangling leash. But a new brain-imaging study suggests that dogs may even be able to distinguish between certain negative emotions without using clues like our body language, odor or words. Just looking at people’s faces may be enough, scientists report August 10 in iScience. The results offer a new peek at what’s going on in canine brains. That could help scientists better understand how dogs’ emotion-sensing abilities evolved, says Laura Cuaya, a neuroscientist at the University of Vienna in Austria. In the meantime, the work provides yet another reason to smile at any pup that crosses your path, she says — perhaps they’ll understand. Previous studies have revealed much about dogs’ perception of emotion. They can tell whether a human face is displaying positive or negative emotions, for example. And such emotions seem to arouse different areas of the brain. But many questions remained. Can dogs’ brains differentiate between two negative emotions, such as anger versus fear? Do the faces need to be familiar? Who’s a good boy? Odin and Kun-Kun (right) are two canine participants in a project that examined dogs’ brain activity. Researchers trained the pups to sit still inside an MRI machine while looking at images of human faces. The dogs’ brains lit up in different patterns depending on what emotions people’s faces displayed. © Society for Science & the Public 2000–2026

Keyword: Emotions; Evolution
Link ID: 30369 - Posted: 08.12.2026

Lynne Peeples Every heartbeat is choreographed not just by the brain but also by a mysterious nervous system embedded in the heart itself. Now, scientists studying mice have started to unravel how this complex system works to keep the heart beating steadily even at times of extreme stress — findings that challenge the classic view that all cardiac neurons are alike. “The key is to keep the heart functional no matter what happens. Because if the pump function stops, you will die,” says Rui Chang, a neuroscientist at Yale University School of Medicine in New Haven, Connecticut, and co-author of the new paper. The findings, published today in Cell1, could inform better treatments for heart disease. Like the gut’s widely recognized ‘second brain’, the heart contains a mini-brain of its own — known, more formally, as the intrinsic cardiac nervous system. This network of neurons is embedded in the fat pad surrounding the heart. The system’s neurons exchange messages with the brain and with each other, and are the final players in a long chain of neurons that controls cardiac function. But because intrinsic cardiac neurons are exceedingly rare, making up only about 0.01% of the cells in a piece of heart tissue, their precise roles have been hard to pin down, says Chang. Damage from a heart attack comes from brain signals, mouse study suggests To fill that gap, his team genetically engineered mice to label all of the animals’ cardiac neurons. The scientists sequenced genes isolated from these neurons and identified markers for two neuronal subtypes. They then used techniques such as high-resolution imaging to identify the genetically distinct subtypes’ core functions and to map their locations. © 2026 Springer Nature Limited

Keyword: Emotions
Link ID: 30336 - Posted: 07.22.2026

BY Christie Wilcox Goats spend a lot of time bashing their heads into things. Winning a headbutting contest shows other members of the herd who’s boss—but bumping heads is also a way to play or explore new objects, so it’s often assumed goats must be protected against head injury by the shape of their skull and strong neck muscles. A new study challenges that assumption. Researchers have found early signs of neurodegeneration in headbutting goats at just 1 year old, they report in a preprint posted to bioRxiv this month. The findings, they say, suggest goats could be a useful animal model for studying the link between head injuries and neurodegeneration seen in humans. “I think the overall conclusions are pretty convincing,” says Ramon Diaz-Arrastia, a neurologist at the University of Pennsylvania who was not involved with the work. Traditionally, researchers have used rats and mice as animal models for studying brain injuries, and the field has become a “rodent monoculture,” he says. But rodent and human brains are very different, which could be partly to blame for the poor translation of preclinical findings to human trials, so it’s “really interesting to see this work in goats.” Nicole Ackermans, a neuroscientist at the University of Alabama, first identified signs of neurodegeneration in wild headbutting animals in 2022, finding that the brains of dead muskoxen contained an abnormal version of the protein tau. In humans, these tangled tau proteins are associated with neurodegenerative diseases such as Alzheimer’s, and can form after head injuries. “I thought, ‘OK, this is something really interesting to look at for modeling brain damage,’” she says. But tracking how damage accumulates over time in wild animals is not feasible. That’s where the goats came in. The team acquired three 6-month-old male goats—Alvin, Simon, and Theo—from farms and moved them to a nearby agricultural college where cameras recorded them for 6 months to track their headbutts. Each month, the researchers collected samples of blood, saliva, and brain fluid to look for biomarkers of brain injury and, at the start and end of the study, scanned the animals’ brains using positron emission tomography–MRI to spot any structural damage. © 2026 American Association for the Advancement of Science.

Keyword: Brain Injury/Concussion; Aggression
Link ID: 30335 - Posted: 07.22.2026

By Jake Currie Humans are social animals, so seeing a fellow human face triggers a cascade of activity in our brains. Information about the age, gender, familiarity, emotional state, and more get processed within milliseconds. Now, new research published in the journal Developmental Cognitive Neuroscience suggests how our brains respond to faces in our youth could impact our social lives later on. ​​“Faces contain a lot of social information, and perceptually or cognitively humans process that information really, really quickly,” study author Myles N. Arrington said in a statement. “That makes it great for neuroscience, because as soon as you show a face to a person it doesn’t take long for their brain to respond.” Arrington and his fellow neuroscientists at the University of California, Davis studied brain activity of almost 6,000 children between the ages of 8 and 11 from the Adolescent Brain Cognitive Development Study. The kids were shown pictures of faces displaying positive, negative, and neutral emotions (which contain loads of social information) and places (which contain none) while their brain activity was monitored on an fMRI machine. Combining the fMRI results with two-year follow-ups, they found that increased activity in the amygdala—the brain’s fight-or-flight center—in response to faces was correlated with changes in their social lives. Interestingly, boys and girls with heightened amygdala activity had much different results later in life. Girls with more active amygdalas tended to have more involvement with peers two years down the road, while boys showed less involvement. According to the researchers, this could be due to differences in how the two genders are socialized. For example, “boys may be socialized to withhold intimacy and distance themselves from their peers,” the team wrote. It’s possible that this socialization can impact how their developing young minds process the social information contained in faces. © Copyright 2026

Keyword: Emotions; Sexual Behavior
Link ID: 30324 - Posted: 07.15.2026

Stephanie Dorais You slide your hand into your coat pocket and find an old, folded $100 bill. In the other pocket, you find a coin. Now, here’s the gamble: flip the coin. Heads, you win another $300. Tails, you hand over your $100 bill. Do you take the risk? Mathematically, you should. One coin flip gives you two equally likely futures: in one, heads, you gain $300; in the other, tails, you lose $100. Because each future has a 50 per cent chance of happening, you count half of each outcome: half of $300 is $150, and half of $100 is $50. Balance those against each other, and taking the gamble puts you $100 ahead on average. Decision scientists call this positive expected value. Even when someone grasps the mathematics, however, it’s hard to take the risk. Why? About 50 years ago, the psychologists Amos Tversky and Daniel Kahneman showed that this hesitation is not random. People depart from logic in patterned ways. One of the most durable patterns is loss aversion: our tendency to feel the pain of losing more sharply than the pleasure of an equivalent, or even greater, gain. This is where mindfulness becomes interesting. Mindfulness is usually defined as paying attention to the present moment, on purpose, without immediately judging what is happening. In practice, that can mean noticing a thought before believing it, feeling an emotion before acting on it, or returning attention to the body, the breath, or the world around you. At its simplest, mindfulness creates a pause between what arises in the mind and what we do next. That pause helps because many of our choices are made before we have fully examined them. We may think we are deliberating over the coin toss, but often the body has moved first: recoiling from loss or preserving a decision simply because we have already invested in it. These mental shortcuts are called cognitive biases, and the study of this kind of human misjudgment is central to decision science. © Aeon Media Group Ltd. 2012-2026.

Keyword: Attention; Emotions
Link ID: 30319 - Posted: 07.11.2026

By Natalia Mesa If a longtime friend suddenly becomes a foe, like Brutus to Caesar or Iago to Othello, the brain must update the person’s feelings about the betrayer without altering memories of who that companion is. The hippocampus may sometimes store both pieces of information, but when it comes to updating feelings, it keeps identity and emotional valence separate, according to a mouse study published today in Science. “We found the neural mechanisms that underlie emotion toward others,” says study investigator Teruhiro Okuyama, professor at the Institute of Quantitative Biosciences at the University of Tokyo: Memory-storing neurons in the hippocampus remain relatively stable, but the strength of their connections to the basolateral amygdala neurons shift, the study shows. Okuyama and his colleagues used chemogenetics to induce aggression in previously docile mice and optogenetics to trace how hippocampal circuits change in the animal’s cagemate. They found that they could both “write and erase social memories” by targeting specific neuron populations. “It’s truly unbelievable how much they did in this paper,” says Robert Malenka, professor of psychiatry and behavioral sciences at Stanford University, who was not involved in the work. “They did a beautiful job of taking three brain areas and defining the connectivity and the cell-type-specific connections that are responsible for the phenomenon they’re studying.” Neurons in the hippocampus store social memories and segregate positive and negative ones, previous work shows. But most past work has studied how negative run-ins with unfamiliar animals affect behavior. © 2026 Simons Foundation

Keyword: Aggression; Sexual Behavior
Link ID: 30318 - Posted: 07.11.2026

By Libby Riddle A bear might seem like the scariest thing you could run into in a national park. But a new study suggests maybe you should be more worried about elk. Out of nearly 3,000 wildlife incidents in Canadian national parks, more than half involved an elk, researchers report July 2 in Frontiers in Conservation Science. But the risk of tangling with a given species also depended on what people were doing, say Holly Landles and conservation biologist Shashank Balakrishna of the University of York in England. Camping out? Be wary of elk grazing near your campsite. Quietly hiking or wildlife watching? Watch out for bears using the same trails. “By identifying situations where a potential conflict scenario is more likely, we can help visitors make informed decisions that improve safety whilst also reducing unnecessary disturbance to wildlife,” says Landles, who conducted this research as an undergraduate at York. Landles and Balakrishna analyzed 2,878 aggressive wildlife incidents from 2010 to 2023 involving five animals: black bears, grizzly bears, elk, coyotes and mule deer. Aggressive behaviors included chasing, attacking or bluffing a charge. The analysis identified which animal–human activity combinations were especially risky. Elk topped the list, involved in 62 percent of all the incidents. One of the riskiest combos was elk and camping — the animals turned up in 84 percent of campground incidents. This may be because Canada’s peak camping season aligns with when the animals mate and give birth — times of heightened aggression for the species. “Elk are herbivorous herd animals that don’t immediately inspire fear like a carnivore does,” Balakrishna says. Visitors may underestimate how aggressive they can be. © Society for Science & the Public 2000–2026.

Keyword: Aggression
Link ID: 30308 - Posted: 07.04.2026

By Emily Anthes Humor is deeply personal. A punchline or a pratfall that leaves one person doubled over in delight might elicit blank stares from another. But laughter is universal, an innate instinct shared by humans everywhere. And not just humans. Chimps chuckle, gorillas guffaw, bonobos bust a gut. All the planet’s great apes laugh, and they often do so in the same kind of regular, repeating rhythm that humans do, scientists found in a small new study. The research sheds light on how laughter evolved with and among great apes, becoming faster and more variable in humans than in these other primate species. While nonhuman apes appeared to laugh in ways that were largely fixed, humans were more flexible in their expressions of mirth, changing up the tempo of their chuckles depending on the circumstance, the scientists found. “I think we can say we are the masters of laughter,” said Chiara De Gregorio, a research fellow at the University of Warwick in Britain and an author of the study. “We can have a small, polite laugh in front of the Queen of England, and then we are in the pub with our friends, and we laugh so much in a different way. We can even laugh in a way that communicates to the other person that we actually didn’t find the joke they said funny.” This wide-ranging repertoire requires significant vocal flexibility and control — the same skills that humans would have needed for spoken language. The study demonstrates the “uniqueness of human laughter,” said Greg Bryant, a cognitive scientist at the University of California, Los Angeles, who was not involved in the new research. “It provides a window into human vocal evolution.” In the new study, which was published on Thursday in the journal Communications Biology, the researchers analyzed the recorded laughter of four children and 13 young, captive apes: four orangutans, two gorillas, three bonobos and four chimpanzees. Some of the recordings featured laughter produced during play, while others captured laughter elicited by tickling. © 2026 The New York Times Company

Keyword: Emotions; Evolution
Link ID: 30298 - Posted: 06.27.2026

A San Francisco startup with ties to Elon Musk’s Neuralink has started testing its brain implant to detect and treat cancer in humans. Coherence Neuro says it temporarily placed its coin-sized implant in the brains of three people undergoing surgery to have brain tumors removed at the Royal Melbourne Hospital in Australia. The implant was in place for roughly 30 minutes before being removed, providing an important safety check before the device can be implanted long-term in patients with brain cancer. Known as a brain-computer interface, the Coherence Neuro device is designed to sense the unique electrical signals of tumors and deliver mild electrical stimulation to prevent their growth. In the time the implant was in the patients’ brains, the company was able to see how it performed for a short period. (The patients had consented prior to surgery.) Matthew MacDougall, Neuralink’s head neurosurgeon, is an adviser and investor in Coherence. Rory Murphy, a neurosurgeon at the Barrow Neurological Institute in Arizona who is an investigator in one of Neuralink’s trials, is also slated to be involved in future trials of the Coherence device. The idea behind treating brain tumors with electrical stimulation comes from the long-held observation that cancerous tissue has distinctive electrical properties. “These are electrical conditions, just like epilepsy, just like depression. This is a network problem in the brain,” says Ben Woodington, chief executive officer and cofounder of Coherence. © 2026 Condé Nast.

Keyword: Biomechanics
Link ID: 30296 - Posted: 06.24.2026

By Victoria Clayton About 14 years ago, Chrissi Kelly lost her sense of smell. She had traveled to the Czech Republic to visit family and caught some virus. Months later, when she still couldn’t smell, she made the rounds to doctors, including her general practitioner and an ear, nose and throat specialist, trying to find answers. She was diagnosed with anosmia (smell loss), and like many patients with her condition, was told she’d have to learn to live with it. But for her, the loss was catastrophic. “After about six months of complete loss, I was just climbing the walls, and I did not feel like myself anymore,” she says. Researchers estimate that up to 22 percent of the population lives with smell impairments, like hyposmia (partial smell loss) or anosmia (complete smell loss). And many others live with smell disorders like phantosmia, in which a person picks up phantom smells, or parosmia, where typically pleasant scents like coffee or shampoo begin to register as highly unpleasant (think feces or vomit). Yet the conditions have been poorly understood, underdiagnosed and often minimized by clinicians. Photos of shampoo, coffee, trees and logs. A world without scents or with warped ones can feel deeply unfamiliar. When our sense of smell goes awry, normally pleasant scents such as shampoo or coffee may be perceived as disgusting, or strong, unmistakable odors such as pine trees in a forest or fresh-cut lumber may fail to be registered at all. The pandemic changed that. Covid brought unprecedented attention — and research interest — to the sense of smell. There have been 780 million reported cases of Covid-19 since December 2019 (and many more unreported), according to the World Health Organization, and smell loss is a well-known symptom. In one 2023 survey published in the journal Laryngoscope, 60 percent of individuals with Covid experienced smell loss, most temporarily, but some over the longer term.

Keyword: Chemical Senses (Smell & Taste); Emotions
Link ID: 30289 - Posted: 06.20.2026

By Elizabeth Preston To our human eyes, a mouse’s furred face doesn’t betray much emotion. But if you watch the body language of a mouse who’s reunited with one of her sisters after five days in a cage alone, you might suspect you know what she’s feeling. The formerly isolated mouse chatters in squeaks too high for a human to hear. She follows her sister, crawling beneath the other mouse’s body as if trying to get a hug. She looks like she’s feeling what you or I feel when meeting a long-lost friend or a family member — maybe with more sniffing. Loneliness isn’t just for humans, and neither are its harms. Over the past decade or so, some researchers have come to believe that an animal’s craving for the company of others isn’t just a preference, but a basic, deeply held need. When we don’t socialize enough, we feel the lack like hunger or thirst, they say. When we’ve had our fill of togetherness, we feel satisfied or quenched. The amount of socializing a creature needs may be particular to that species, and even to that individual. Scientists have found within-species social differences in birds, monkeys, fish and even cockroaches. Among humans, “you can feel lonely at a party, or you can feel fine alone in your office,” says Kay Tye, a neuroscientist at the Salk Institute for Biological Studies in California. Whatever the ideal degree of togetherness, Tye and others think that an animal’s need to balance time alone and time with others represents a kind of homeostasis: an equilibrium that’s critical for survival. Today, they are on a hunt to find where, in the brain, this equilibrium is controlled — and hoping their work will hold dividends for lonely humans.

Keyword: Emotions; Evolution
Link ID: 30269 - Posted: 06.06.2026

By Hannah Thomasy Prairie voles have a reputation as one of the most social rodents, but when Aubrey Kelly tried to use them to study the neurobiology of group dynamics, she discovered limits to their sociability. “Prairie voles are indeed super social with their pair-bond partner and with their offspring,” says Kelly, associate professor of psychology at Emory University. “But if an adult prairie vole encounters a stranger, they’re going to fight—oftentimes to the death.” She shifted her focus to paternal care in the voles but stayed on the lookout for a truly social rodent that lived in rich, complex communities. As a graduate student, she had studied the neural circuitry that contributes to such societies in zebra finches, and she hoped to make similar inroads in mammalian brains. “I got really into the idea of animal societies and how individuals can just get along in big groups, which is something that we do ourselves,” Kelly says. About four years later, a colleague introduced her to spiny mice. Despite their name, these animals are more closely related to gerbils than to laboratory mice. They live in large, flexible, mixed-sex groups and rarely brawl, the colleague told her. Kelly was intrigued—perhaps these groups were the miniature mammal societies she had been searching for. Her subsequent work has demonstrated that, indeed, these critters not only tolerate groups but actually prefer them: When given a choice between associating with two peers or eight peers, they spend the majority of their time with the larger group. Now Kelly is digging into the neural mechanisms underlying this communal lifestyle. Kelly spoke with The Transmitter about spiny mouse “friendships,” custom CRISPR tools and the neurobiology of coexistence. © 2026 Simons Foundation

Keyword: Aggression; Hormones & Behavior
Link ID: 30266 - Posted: 06.03.2026

By Elizabeth Pennisi Homing pigeons don’t rely on gut instinct to return to the roost. But a nearby organ — the liver — might point the way. White blood cells in the birds’ livers accumulate iron and act as an internal compass when clouds block the sun that normally helps them navigate, researchers report May 28 in Science. While scientists generally agree that some animals use Earth’s magnetic field to guide migrations, they had not pinned down how, and the new work offers a surprising explanation. For decades, researchers have fiercely debated first if and then how birds sense magnetic fields and use them for navigation. One prominent idea involves proteins in their eyes undergoing a reaction in magnetic fields. No one has been able to prove exactly how this so-called “quantum effect” is in play. Other animals that orient using Earth’s magnetism, such as bats and sharks, lack the proteins, so the debate languished unresolved. Ornithologist Martin Wikelski of the Max Planck Institute of Animal Behavior in Radolfzell, Germany, and immunologist Christian Kurts of the University of Bonn in Germany stumbled on another idea more than a decade ago at a conference coffee break. Kurts mentioned how frustrated he was that immune system cells called macrophages in mouse spleens would stick to magnetic columns in instruments used to separate different types of cells, ruining his experiments. The reason the macrophages were sticking, he discovered, was that they accumulated and recycled damaged red blood cells’ iron atoms, which aligned in magnetic fields. © Society for Science & the Public 2000–2026

Keyword: Animal Migration; Neuroimmunology
Link ID: 30264 - Posted: 05.30.2026

Simon Spichak Acute stress makes it difficult to link memories of past events with fresh information, a study1 suggests. The results help to explain why people struggle to show insight under pressure. The study, published today in Science Advances, combined brain imaging and psychological testing to show how stress disrupts people’s ability to tap into records of previous experiences and make deductions. The combination of behavioural testing and neural imaging “to actually see what’s going awry is really compelling”, says Brice Kuhl, a neuroscientist at the University of Oregon in Eugene, who was not involved in the study. Only connect The brain connects new and old information to make inferences through a cognitive process called integration. For example, if you have a memory of your friend wearing a bright green jacket, and you see a bright green jacket on a park bench, you might integrate your memory and the visual input to infer that your friend is at the park. This ability can be impaired in individuals with some mental-health conditions, such as anxiety disorders and psychosis. The brain area called the hippocampus is essential for integration. Since it is also particularly vulnerable to stress, Lars Schwabe, a cognitive psychologist at the University of Hamburg in Germany, and his colleagues decided to test how acute stress would affect the brain’s ability to integrate information and make inferences. Memory task On the experiment’s first day, 121 participants were asked to memorize a series of paired images, each containing one image of an animal and one image of either a face or a scene. © 2026 Springer Nature Limited

Keyword: Stress; Learning & Memory
Link ID: 30255 - Posted: 05.23.2026