Chapter 11. Emotions, Aggression, and Stress
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By Richard Stone The wind picks up dust from the unpaved road one afternoon in December as Jack van Honk turns into a ramshackle neighborhood in Lambert’s Bay, on the west coast of South Africa. A stocky woman in a red patterned sundress steps out of a small home painted palest sea green, her ochre-dirt yard crowded with potted plants, many medicinal. She smiles broadly, deep wrinkles creasing a face that is cherubic and yet careworn beyond her 47 years. “Doctor! I missed you,” she beams, her husky voice barely more than a hoarse whisper. Maria carries a rare genetic mutation that is almost unknown outside of southern Africa. Its effects have been to calcify a part of the brain called the basolateral amygdala, and to thicken and scar the vocal cords. A friend of Maria with the same condition lives several hours inland, and sometimes they meet when van Honk brings them to Cape Town for brain scans and other tests. “It helps to know I’m not alone,” Maria says. By every measure of daily life — holding down a job, keeping a household running, raising two teenage sons — Maria is competent and engaged. “You talk to her, and you don’t see anything wrong,” says van Honk, a social neuroscientist at the University of Cape Town. She and others he knows with her condition, Urbach-Wiethe disease, “are kind, sweet people by nature.” In an interview in her kitchen, Maria struggles to recollect even a fleeting moment of unhappiness — before mentioning that she kicked out her partner some years ago because of his drinking. Photograph of a woman in a red dress standing in her yard. Maria lives with a rare genetic disorder that damages part of the amygdala — a brain region increasingly linked not just to fear, but to how humans weigh the needs of others.
Keyword: Emotions
Link ID: 30246 - Posted: 05.16.2026
By Hannah Thomasy For nearly a decade, Vincent Bombail has been tickling rats. It’s been a standard technique used in the study of animal happiness. But not all rats particularly enjoy the experience, data show. Female rats prefer gentler, more playful tickling than males, Bombail and his colleagues report April 15 in Biology Letters. The findings suggest that the same physical experience evokes a different emotional response in different individuals, potentially influencing the results of studies on animal happiness. “This research helps us understand these animals as playful but also rich and complex and having opinions,” says Daniel Weary, an animal welfare scientist at the University of British Columbia who was not involved in the study. “Understanding the affective lives of animals is actually one of the coolest and most difficult questions there is in science,” he says. As early as the 1930s, researchers deliberately exposed rats to standardized negative experiences to study the physical effects of stress. Figuring out how to study positive experiences took longer. It wasn’t until the 1990s that researchers developed the standard tickling protocol, where a researcher flips a rat over, pins it on its back and tickles its belly. The protocol is intended to mimic the rough-and-tumble play of young male rats. © Society for Science & the Public 2000–2026.
Keyword: Emotions; Evolution
Link ID: 30242 - Posted: 05.16.2026
By Alonso Daboub Brain cells that help make us human are also uniquely vulnerable to multiple sclerosis. A newfound cellular repair kit can’t keep up with the disease’s damage, leading to the cell death that’s a hallmark of progressive MS, researchers report April 1 in two papers in Nature. The discovery uncovers an important and underexplored mechanism behind how the condition progressively shrinks the brain. By better understanding how MS kills brain cells, scientists can design treatments aimed at preventing cognitive decline, says David Rowitch, a developmental neuroscientist at the University of Cambridge. Each year, 10,000 people in the United States are diagnosed with MS. The body’s immune system attacks neurons in the brain, causing inflammation and unpredictable flare-ups of muscle weakness, tingling and pain. Research has primarily focused on the way the disease causes nerve fibers to lose myelin, the fatty insulation that helps them send messages. But in a second, progressive phase, neurons in the brain begin to die. Patients experience sharper declines in their cognitive ability, leading to difficulties in memory and reasoning as their brains shrink. “There’s no treatment really for that part,” says Steve Fancy, a neuroscientist at the University of California, San Francisco Previous research identified a specific group of neurons in the human cortex, the brain’s wrinkly outermost layer, that are particularly vulnerable to degeneration in progressive MS. Called CUX2 neurons, these brain cells help make up two layers of the cortex thought to play an important role in things like cognition and computation. These layers in the brain are “really very important for making us human,” Fancy says. © Society for Science & the Public 2000–2026.
Keyword: Multiple Sclerosis
Link ID: 30238 - Posted: 05.09.2026
By Kristen French What is a cat, and how do we know when we’ve encountered one? This question may be harder to answer than it seems. Neuroscientists Lisa Feldman Barrett and Earl Miller say people typically think about categories such as cat and apple backward—bottom-up instead of top-down. In reality, you don’t hear a meow, and see whiskers and paws and then conclude, “Cat!” Before any of this happens, your brain has sent signals about a “cat hypothesis”—and a plan for how to respond to a cat—to your body, based on past experience, Barrett and Miller say. This cat hypothesis, in turn, actively orchestrates what signals your body processes and how. In other words, the brain constructs classifications on the fly, and we’re not even conscious this is happening until after the fact. Barrett, a renowned Harvard neuroscientist and psychologist who has written for Nautilus and is best known for her theory of constructed emotion, teamed up with Miller to review “converging” evidence from a wide range of disciplines: neuroanatomy, electrophysiology, brain imaging, and cognitive science. The pair published their results recently in Nature Reviews: Neuroscience. Their new theory of categories has a lot in common with Barrett’s theory of how emotions work. She argues that emotions aren’t hardwired universal reactions, but are instead predictions constructed rapidly and in the moment from internal bodily sensations, past experiences, and cultural context. While her work on emotions has been highly influential, it remains an active subject of debate in the field of psychology. I spoke with Barrett and Miller about what they call “folk psychology,” and how their theory of categorization relates to so-called beginner’s mind, human bias, and objectivity and mental illness. We also talked about Nobel Laureate Daniel Kahneman’s modes of thinking fast and slow. © Copyright 2026
Keyword: Attention; Emotions
Link ID: 30226 - Posted: 05.02.2026
By Ellen Barry Edna Foa, an Israeli American psychologist who pressed her field — and her patients — to more directly confront fear and anxiety, revolutionizing the treatment of post-traumatic stress disorder, died on March 24 at a hospital in Philadelphia. She was 88. Her death, from complications of pneumonia, was confirmed by her daughter Yael Foa. Dr. Foa completed her training in the late 1960s, when clinicians tended to treat people with severe anxiety disorders cautiously and gradually. One of her first patients, a woman with an intense fear of objects related to death, had been prescribed a course of “systematic desensitization.” Dr. Foa was instructed to visit her every day carrying a small stone from a cemetery, bringing the stone a little closer each time until at long last the patient would be able to hold it. “We started to feel that she will never get better at that rate,” Dr. Foa recalled in a 2018 podcast interview. Dr. Foa decided to move faster, driving the patient to a funeral home and bringing her inside so that the woman was forced to deal with her distress. Avoiding those feelings, Dr. Foa posited, was actually holding the patient back. This theory culminated, about a decade later, in Dr. Foa’s landmark innovation. In the 1980s, she developed prolonged exposure therapy, a structured protocol of eight to 12 90-minute sessions in which the patient recounts a traumatic event in the present tense, lingering on the most vivid and upsetting elements. Then the patient undertakes real life exposure to reminders of the event. These sessions could be uncomfortable, Dr. Foa acknowledged. But they served to ease the patient’s sensitivity and correct flawed thinking, demonstrating that there was no harm in confronting the feared object, place or event. Over the years that followed, a series of studies supported the approach’s effectiveness. © 2026 The New York Times Company
Keyword: Stress
Link ID: 30203 - Posted: 04.18.2026
By Michael S. Rosenwald Thomas S. Langner, a sociologist who helped lead a landmark study of New Yorkers that revealed striking insights about the social, cultural and economic forces that shape mental illness, died on March 16 at his home in Sandy Hook, Conn. He was 102. His wife, Susan Kassirer, confirmed the death. When “Mental Health in the Metropolis: The Midtown Manhattan Study” was published in 1962, headline writers had a field day with the top-line finding: that only 18.5 percent of Manhattan residents could be considered psychologically well adjusted, while 23 percent showed significant impairment in daily functioning. “City Gets Mental Test, Results Are Real Crazy,” Newsday declared. The Daytona Beach Morning Journal wondered: “New York Living for ‘Nuts’ Only?” The actual substance of the two-part study — the second installment appeared in 1963 — was the challenge it posed to the widely held view in psychiatry that biological and individual factors are the primary drivers of mental illness. Professor Langner, along with a team of psychiatrists, anthropologists and social workers at Cornell University Medical College (now Weill Cornell Medicine), spent more than a decade studying 1,660 people who lived on the East Side of Manhattan, between 59th and 96th Streets. The researchers concluded that developing mental illness didn’t simply come down to a genetic lottery. © 2026 The New York Times Company
Keyword: Stress; Schizophrenia
Link ID: 30198 - Posted: 04.15.2026
By Claudia López Lloreda A previously unrecognized population of fibroblasts seals off the base of the choroid plexus—the network of blood vessels and cerebrospinal-fluid-producing epithelial cells that line the ventricles—from the cerebrospinal fluid (CSF) and the rest of the brain, a new study in mice shows. The newly identified barrier provides an added layer of protection that is distinct from the well-known blood-brain barrier and the one that the epithelial cells form between the blood and the CSF. The findings help settle a long-standing debate about whether there was a blind spot in the choroid plexus that gave the periphery access into the brain, says Britta Engelhardt, professor of immunobiology at the University of Bern, who was not involved in the work. “Some [scientists] speculated that there is a leak, like an opening, a secret window into the brain, and others said, ‘No, there must be a barrier that we have overlooked.’ And it’s very obvious now.” Fibroblasts at the base of the choroid plexus, connected by adherens and tight junction proteins, cluster together around blood vessels and form a sealed barrier in mice, the researchers found. This structure represents a crucial component of compartmentalization in the choroid plexus, Engelhardt says. The cells were also present in human postmortem brain samples. Similar to other barriers, the seal becomes leaky in response to inflammation triggered by lipopolysaccharide, a component of the bacterial cell wall, and it may coordinate immune cell crossing from the blood into the brain, the study also showed. The work was published in February in Nature Neuroscience. © 2026 Simons Foundation
Keyword: Neuroimmunology; Drug Abuse
Link ID: 30190 - Posted: 04.04.2026
By Diana Kwon Human minds often wander. Whether we’re busy at work, doing chores or exercising, our thoughts frequently shift away from the task at hand. These spontaneous thoughts sometimes turn toward sensations in the body, such as our heartbeat or breath, and that could affect our immediate emotional state and long-term mental health, researchers report March 25 in Proceedings of the National Academy of Sciences. Many studies focus on thinking about memories, events and other people, what scientists consider the cognitive aspects of mind wandering, says Micah Allen, a neuroscientist at Aarhus University in Denmark. This research suggests that mind wandering plays an important role in planning, learning, creativity and other important mental processes. It has also been linked to negative emotions and some, such as obsessively ruminating on past mistakes, may contribute to depression, attention-deficit/hyperactivity disorder and other mental illnesses. Do you share our vision for a healthier, happier world through science? But how the mind might drift to bodily sensations, what some researchers call “body wandering,” and its effects have largely been overlooked, Allen says. He and colleagues had 536 people lie still in a magnetic resonance imaging scanner and then complete a questionnaire about what was on their minds during that time. In addition to the typical content of daydreams, such as memories, plans or social interactions, participants reported paying attention to sensations in their body, such as their breathing, heartbeats and bladder. The team also found evidence of this in the MRI scans: Body wandering appeared to have a distinct brain signature from that of “cognitive” mind wandering. © Society for Science & the Public 2000–2026.
Keyword: Stress; Attention
Link ID: 30188 - Posted: 04.04.2026
By Ellen Barry When Cohen Miles-Rath walks into his father’s house, the history of his psychosis is right there in front of him. There is the place where he was standing when he received a cryptic message on his phone: The devil had entered his father’s body. There is the drawer where he spotted a knife whose handle was white — the color of God! There is the floor where, as they grappled over the knife, Cohen bit off part of his father’s earlobe, and blood spattered over both of them. There is the spot where, pinned to the floor, Cohen reached up with the knife and slashed wildly at his father’s throat. The violence lasted seconds but changed his whole life. With voices still racketing in his head, Cohen found himself in jail, facing charges of second-degree assault and criminal mischief, felonies punishable by up to 10 years in prison. Stunned and bleeding, his father had pressed charges, and taken out a restraining order against him. But Cohen hadn’t killed him. In the years that followed, he had the feeling that he had walked right up to the edge of a chasm. About 300 times a year in the United States, a child kills a parent, making up around 2 percent of all homicides. A large portion of these cases involve people like Cohen: young men with severe mental illness who are living at home. When mounting symptoms of psychosis make school or work impossible, parents are the support system of last resort. Paranoid delusions can cruelly invert that logic, turning people against the figure closest to them. © 2026 The New York Times Company
Keyword: Schizophrenia; Aggression
Link ID: 30186 - Posted: 04.01.2026
By Andrew Jacobs Over the past two years, Australia, a country long known for its strict drug laws, has been allowing psychiatrists to treat post-traumatic stress disorder with MDMA, the chemical compound better known as Ecstasy or molly. The early results have been striking, researchers say, with more than half of patients who received MDMA along with psychotherapy reporting significant relief from PTSD. Just as notably, Australian drug regulators have not recorded any serious adverse events among the nearly 200 patients who have been through the program, which includes up to three dosing sessions with MDMA, a synthetic stimulant that promotes empathy, emotional connection and feelings of euphoria. That data point is especially relevant given the contentious debate in the United States over the safety of MDMA — one that in 2024 helped sink the prospects for MDMA therapy at the Food and Drug Administration. “Compared to conventional treatments, the outcomes we’re seeing to date with MDMA-assisted therapy have been extraordinary,” said Dr. Ranil Gunewardene, a psychiatrist in Sydney who has treated more than 40 patients since the Australian regulators created a legal pathway for the drug. But Australia’s experiment with psychedelic medicine also highlights the limitations and constraints that the nascent field is likely to face as it gains wider attention from regulators and practitioners. Because Australia is the first country to legalize and regulate MDMA therapy, researchers have been especially eager for real-world data about a drug that has been pejoratively associated with rave culture. © 2026 The New York Times Company
Keyword: Stress; Drug Abuse
Link ID: 30177 - Posted: 03.25.2026
By Sarah Scoles When George W. Maschke applied to work for the FBI in 1994, he had already held a security clearance for over 11 years. The government had deemed him trustworthy through his career in the Army. But soon, a machine and a man would not come to the same conclusion. His application to be a special agent had passed initial muster. And so, in the spring of 1995, according to his account, he found himself sitting across from an FBI polygraph examiner, answering questions about his life and loyalties. He told the truth, he said in an interview with Undark. But in a blog post on his website, he recalled the examiner told him that the polygraph machine — which measured some of Maschke’s physiological responses — indicated that he was being deceptive about keeping classified information secret, and about his contacts with foreign intelligence agencies. After a failed polygraph exam in which he says he told the truth, George Maschke eventually co-founded the advocacy website AntiPolygraph.org. “My entire career prospects were basically shattered,” said Maschke. “How could I have told the truth and failed the polygraph?” He wanted an answer. And so soon after his failed exam, he said he went to the research library to try to learn more about what had transpired between his body, that machine, and the measuring man. Further spurred by another negative polygraph experience, the resulting deep dive on polygraphs and examination methods eventually led him to co-found the advocacy website AntiPolygraph.org. “When I had my polygraph experience, I had no one to talk to,” said Maschke, who went on to work as a legal translator in the Netherlands. He hoped his public-facing website meant others wouldn’t have that experience.
Keyword: Stress
Link ID: 30175 - Posted: 03.25.2026
By Holly Barker Astrocytes—but not neurons—in the amygdala encode anxiety-like states in mice, according to a paper published today in Neuron. The findings suggest that the cells—which are altered in people with some neuropsychiatric conditions, including autism—contribute to mental health difficulties documented in such groups. “In a very sophisticated way, the [study] shows that astrocytes are these core computational cells for highly complicated behaviors,” says Michael Wheeler, assistant professor of neurology at Harvard University, who did not contribute to the new work. “Astrocytes are understanding and signaling computations in these circuits.” Violent movies and other stressful stimuli activate the amygdala, human imaging studies have shown. And in mice, neurons in the basolateral amygdala are active when the animals are placed in exposed environments, which they find aversive, previous research has found. But that neuronal activity appears to mark shifts between defensive and exploratory behaviors rather than tracking anxiety-related ones, according to a later study. The new findings suggest that astrocytes not only help neurons to regulate anxiety—as previous studies have shown—but “instruct local neurons from the top down,” says study investigator Ciaran Murphy-Royal, associate professor of neuroscience at the University of Montreal. The cells’ activity appears to function as a “safety signal,” that relays danger to other brain regions, he says. Murphy-Royal and his colleagues used calcium imaging to measure astrocytic activity in the mouse basolateral amygdala. Calcium release tracked with freezing, hesitancy and other behaviors reminiscent of anxiety as mice investigated various environments, the team found. In the elevated plus maze, for example, astrocyte activity rose when the rodents explored an open arm of the maze and surged whenever mice peeked over the edge of the suspended setup. © 2026 Simons Foundation
By Simon Makin A brain repair kit that helps yaks and other animals naturally cope with low oxygen levels at high altitudes may point to a new way to treat brain diseases such as multiple sclerosis. In mice with brain damage that mimics MS, the kit’s tools lessened signs of damage in young mice exposed to low oxygen and improved symptoms of MS in adult mice, researchers report March 13 in Neuron. Previous research found that animals living on the Tibetan Plateau, such as yaks and antelopes, carry a mutation in a gene called Retsat. Their lowland counterparts lack the mutation, leading scientists to suspect that it helps protect the brain in low-oxygen environments. “People usually think it’s because of better lung capability, but I wondered whether evolutionary adaptation changes the brain,” says Liang Zhang, a neuroscientist at Shanghai Jiao Tong University. In particular, he was intrigued that these animals have normal white matter in their brains. White matter makes up about half the brain; it consists of bundles of nerve fibers that allow different brain regions to communicate. This neural wiring is wrapped in myelin, a fatty substance that ensures nerve fibers conduct signals efficiently. In MS, the immune system attacks myelin, leading to neurological symptoms and problems with balance and coordination. Myelin production requires a lot of energy, which the brain gets from oxygen. Low oxygen levels, known as hypoxia, can therefore disrupt myelination. During gestation, such disruption can lead to conditions such as cerebral palsy in newborns. © Society for Science & the Public 2000–2026.
Keyword: Multiple Sclerosis; Neuroimmunology
Link ID: 30160 - Posted: 03.14.2026
By Viviane Callier The difference between a doting dad and a deadbeat one may come down to a molecular switch in the brain — at least in African striped mice. Boosting activity of a particular gene in part of the brain known for regulating maternal care turned nurturing males into standoffish ones and even, in some cases, into mouse pup killers, researchers report February 18 in Nature. The findings reveal how social context can alter gene activity in the brain and thereby shape male caregiving. Male caregiving is prevalent in fish and amphibians, suggesting that it is a very ancient behavior in vertebrates. Among mammals, however, fewer than 5 percent of species have fathers that stick around to raise their young. Male African striped mice (Rhabdomys pumilio) are one of the exceptions to the rule, though they vary a lot in their nurturing tendencies, making them an ideal species in which to study the factors that influence this behavior. Some look after the young and groom them; others ignore the pups or even attack them. The same male could become aggressive or doting. To understand that behavior, comparative neurobiologist Forrest Rogers and his colleagues observed the mice’s social environment. In laboratory settings, group-housed males tended to be aggressive toward mouse pups when introduced to them. But surprisingly, when these males were moved to be housed alone, they became very paternal. “I thought clearly something must be wrong, because all the work we know of in mice and rats is that if you socially isolate them, they become very anxious and often not the most caring of individuals,” says Rogers, of Princeton University. But the lone African striped male mice didn’t seem anxious at all. © Society for Science & the Public 2000–2026.
Keyword: Sexual Behavior; Aggression
Link ID: 30159 - Posted: 03.14.2026
By Robert Draper The hallucinations began the moment I lay back onto the mat and pulled the mask over my eyes. Oh, I instantly thought, this is not at all what I expected. The first images were assembled like a film strip, a sharply focused Technicolor row of strong, grim-faced men who appeared to be some sort of tribal chiefs. Within seconds, a green tint covered their faces, which then dissolved, replaced by images of conflict. Bodies strewed across a battlefield. Starving children. They, too, dissolved. A pile of rocks took shape. From the pile, several long, dark snakes slithered out. This could be unpleasant, I thought. A crackling sensation coursed through my entire body, as if all my neurons were firing — not in any way painful, but also inescapable. I could feel my hands sweating. My ears buzzed, and it wasn’t long before I heard the murmuring voices of people who weren’t there, followed by the sound of puking from people who were. There were 11 of us in the treatment room, in a basement in a cottage that overlooked the Pacific Ocean just south of Tijuana, Mexico, where ibogaine — a Schedule I drug in the United States — is legal. It was the night before Thanksgiving. We all had our reasons for coming to the treatment clinic called Ambio Life Sciences. Several in the group were veterans suffering from PTSD, traumatic brain injury, substance abuse or some combination of those. A sex-crimes detective had been in a terrible car accident and lost much of her short-term memory. A Marine veteran and blueberry farmer in Georgia was quietly drinking his life away. And there was Erin, a Texas-based corporate consultant who had suffered trauma that began in childhood and continued in the workplace. Erin’s mat was next to mine at the far end of the treatment room. Because we were the only two in the group not to throw up during the 10-hour experience, we later referred to ours as the Quiet Corner. The drug is derived from the Tabernanthe iboga plant, found mainly in Gabon in central Africa. The powerful hallucinogen has long been used there in the initiation ritual that is part of the Bwiti spiritual tradition, involving an intense all-night group ceremony of dance and music and fire-keeping that culminates in a trancelike state. © 2026 The New York Times Company
Keyword: Stress; Drug Abuse
Link ID: 30156 - Posted: 03.11.2026
By Natalia Mesa Most male mammals do not dote on their young and may even attack them, but some African striped mice actively feed, groom and nuzzle their own and even others’ pups. These profound behavioral differences come down to a single gene: agouti. This gene controls pigment production in the hair or skin of many animals. But in African striped mice, it also acts as a volume knob to silence caregiving circuits in the brain, according to a study published today in Nature. “It’s remarkable that this one gene is able to lead to a dramatic change in behavior,” says Robert Froemke, professor of genetics, neuroscience and otolaryngology at New York University, who was not involved in the work. Male African striped mice that live in isolation for roughly 2 months after weaning tend to nurture pups later in life, even those that are not their own, whereas their peers that live with other mice tend to be indifferent fathers or even infanticidal, the study found. The fatherly mice express lower levels of agouti in the brain compared with their more aggressive counterparts, the study shows. “Agouti, we think, is a molecular integrator of environmental experience,” says study author Ricardo Mallarino, associate professor of molecular biology at Princeton University. Despite the fact that only about 5 percent of mammalian species show fatherly behavior, parental care may be the default mode in striped mice, the research suggests. Both males and females use the same brain circuitry to care for their young, but enhanced agouti expression in the brain suppresses these instincts in the former. © 2026 Simons Foundation
Keyword: Sexual Behavior; Aggression
Link ID: 30133 - Posted: 02.21.2026
By Meghan Rosen Ozempic’s key ingredient may act directly on cartilage to repair creaky joints. In mice and people, semaglutide can ease symptoms of the joint disease osteoarthritis and thicken the cartilage pillowed between bones, researchers report February 9 in Cell Metabolism. Thicker cartilage suggests the tissue is being rebuilt, says Di Chen, a physician and biologist at Shenzhen University of Advanced Technology in China. “That’s a good thing,” he says. “That’s the key thing.” More cartilage means more cushion, which means less bone-on-bone grinding and less pain. Osteoarthritis is the most common form of arthritis, affecting more than 500 million people worldwide. The disease can affect the hands, knees, hips and other joints, causing severe pain as cartilage wears away and tissues inflame. There’s no cure, and no medications that prevent it from becoming worse. Doctors can only help patients try to manage pain, Chen says. Scientists think weight loss can help alleviate symptoms by reducing the load on joints. That’s why semaglutide, the smash weight loss drug in Ozempic and Wegovy, is considered a contender for osteoarthritis treatment. And indeed, in 2024, a clinical trial in people with obesity reported that the drug improved joint pain and function. Doctors assumed those benefits were due to weight loss, Chen says. His team wasn’t so sure. The researchers conducted a similar study in mice with a form of osteoarthritis. One group received semaglutide, the other did not. In the drug-free mice, Chen’s team restricted food intake to match that of the semaglutide group. Both groups shed weight, but only the treated mice saw joint-based benefits. These mice had less pain, less broken-down cartilage and more cartilage growth, the team found. The results suggest that weight loss isn’t driving semaglutide’s benefits. © Society for Science & the Public 2000–2026.
Keyword: Neuroimmunology; Obesity
Link ID: 30129 - Posted: 02.21.2026
By Simon Makin Positive thinking may boost the body’s defenses against disease. Increasing activity in a brain region that controls motivation and expectation, specifically the brain’s reward system, is linked with making more antibodies after receiving a vaccine. The finding suggests these boosts were related to the placebo effect, researchers report January 19 in Nature Medicine. “Placebo is a self-help mechanism, and here we actually harness it,” says Talma Hendler, a neuroscientist at Tel Aviv University. “This suggests we could use the brain to help the body fight illness.” The work is important because it “is first-in-human evidence of a relationship between brain reward systems and immune function,” says Tor Wager, a neuroscientist at Dartmouth College in Hanover, N.H., who was not involved in the study. The study was not designed to test vaccine effectiveness. Larger studies, including more complete immune assessments, will be required to test this association as a medical intervention. Scientists have found many links between the brain and bodily health. Both negative and positive mental states can affect the immune system, and studies in rodents have suggested that the brain’s reward network is involved in these effects. To find out if the same circuitry was at play in humans, Hendler and colleagues trained healthy volunteers to regulate their brain activity using neurofeedback, a technique that uses brain imaging to show users the activity of the area they are trying to boost. The team randomly assigned 85 participants to receive training aimed at increasing activity in either their reward network or a different network, or to receive no training. © Society for Science & the Public 2000–2026.
Keyword: Neuroimmunology
Link ID: 30099 - Posted: 01.31.2026
By Alessio Cozzolino After a heart attack, the heart “talks” to the brain. And that conversation may make recovery worse. Shutting down nerve cells that send messages from injured heart cells to the brain boosted the heart’s ability to pump and decreased scarring, experiments in mice show. Targeting inflammation in a part of the nervous system where those “damage” messages wind up also improved heart function and tissue repair, scientists report January 27 in Cell. “This research is another great example highlighting that we cannot look at one organ and its disease in isolation,” says Wolfram Poller, an interventional cardiologist at Massachusetts General Hospital and Harvard Medical School who was not involved in the study. “And it opens the door to new therapeutic strategies and targets that go beyond the heart.” Someone in the United States has a heart attack about every 40 seconds, according to the U.S. Centers for Disease Control and Prevention. That adds up to about 805,000 people each year. A heart attack is a mechanical problem caused by the obstruction of a coronary artery, usually by a blood clot. If the blockage lasts long enough, the affected cells may start to die. Heart attacks can have long-term effects such as a weakened heart, a reduced ability to pump blood, irregular heart rhythms, and a higher risk of heart failure or another heart attack. Although experts knew from previous research that the nervous and immune systems could amplify inflammation and slow healing, the key players and pathways involved were unknown, says Vineet Augustine, a neurobiologist at the University of California, San Diego. © Society for Science & the Public 2000–2026
Keyword: Neuroimmunology
Link ID: 30098 - Posted: 01.28.2026
By Joshua P. Johansen Growing up in the 1980s in Santa Cruz, California, where redwood-covered mountains descend to the rocky edge of the Pacific, might sound idyllic. But in the dark wake of the drug-fueled ’70s, the beach town could also be frightening. There was a bully at my high school who once chased me down the street threatening to hurt me. Unsurprisingly, catching sight of him in the hallways or at the skate park filled me with dread. Just walking past his house would trigger a wave of anxiety. Yet if I saw him in class, with teachers present, I felt more at ease. How did my brain know to fear him only in specific circumstances? More broadly, how did I infer emotional significance from the world around me? The fact that I or anyone can make these judgments suggests that emotion arises from an internal model in the brain that supports inference, abstraction and flexible, context-dependent evaluations of threat or safety. These model-based emotion systems helped me infer danger from otherwise innocuous features of the environment, such as the bully’s house, or to downgrade my alarm, as I did when an adult was present. Understanding the neural basis of emotion is a central question in neuroscience, with profound implications for the treatment of anxiety, trauma and mood disorders. Yet the field remains divided over what emotions are and how they should be defined, limiting progress. On one side are neurobiologists focused on the neural underpinnings of simple learned and innate defensive behaviors. On the other are psychological theorists who view emotions as subjective experiences arising from complex conceptual brain models of the world that are unique to humans. This divide fuels persistent arguments over whether emotion should be defined primarily as a conscious state or not. Though subjective feelings are undeniably important, limiting our definitions to conscious phenomena prevents us from studying the underlying mechanisms in nonhuman species. To move forward, we need to identify the conserved neural processes that support higher-order, internal-model-based emotional experiences across species, regardless of whether they rise to consciousness. © 2026 Simons Foundation
Keyword: Emotions; Consciousness
Link ID: 30096 - Posted: 01.28.2026


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