By Brianne Kane, Fonda Mwangi, Alex Sugiura, Kylie Murphy, Jeffery DelViscio & Kendra Pierre-Louis In this episode of Science Quickly, journalist Michael Pollan joins Scientific American’s Bri Kane to unpack why consciousness is so hard to define in a discussion that explores what brain science, artificial intelligence experiments and even psychedelics might reveal about how awareness works. Bri Kane: Just to get us going on something really easy I wanted to ask you, Michael Pollan: Are you conscious, do you know if I’m conscious, and are you 100 percent certain that this microphone is not conscious? Michael Pollan: I can’t be sure you’re conscious. I have to infer that from the evidence: that you’re the same species as me, and our species can be conscious, and we have something called philosophy of mind, which is an imaginative faculty that allows us to imagine what other people are thinking. I know I’m conscious, I think. That’s actually the thing we know with the greatest certainty. I mean, [René] Descartes told us that 400 years ago: The only thing we can be sure of is the fact that we exist, and we are conscious. Everything else is an inference. So I’m inferring you’re conscious, and I’m gonna operate on that basis, if it’s okay. And then the microphone, the microphone hasn’t shown me any evidence of consciousness. Kane: So I mean, like you’re saying, there’s only so much evidence to point to for consciousness; some of it is kind of just your gut understanding. And our February cover issue this year was about these 29 different theories of consciousness, which you’ve covered is further evidence that science is really floundering on finding some solid ground on: What is consciousness, and how can we provide evidence to prove this, to tackle this subject with science? But your work seems to really discuss when science and philosophy start rubbing up against each other, which I think is why you get into some really interesting questions in this book. So I wanted to ask you: What theory, out of those 29, do you find yourself leaning towards that seems like the most probable understanding of consciousness? © 2025 SCIENTIFIC AMERICAN,

Keyword: Consciousness
Link ID: 30153 - Posted: 03.07.2026

Rachel Fieldhouse A group of specialized cells play a crucial part in clearing toxic proteins from inside the brain1. But in people with Alzheimer’s disease, these cells malfunction, leading to the build up of tau proteins — a hallmark of the disease. Tanycytes, specialized cells that line the third ventricle of the brain, are unique because they are in direct contact with both the bloodstream and the cerebrospinal fluid (CSF). This means that they can circumvent the blood–brain barrier to allow molecules into and out of the brain. “Tanycytes are highways for the brain,” says Vincent Prévot, a neuroendocrinologist based in Paris at Inserm, the French National Institute of Health and Medical Research. Although it was known that tanycytes transport molecules into the CSF, Prévot and his colleagues are the first to show that tanycytes also transport molecules out of the CSF. In particular, they move tau proteins from the CSF surrounding the brain into the bloodstream. The findings are fascinating, says Amy Brodtmann, a cognitive neurologist and researcher at Monash University in Melbourne, Australia. “No one has looked at these cells before” in relation to Alzheimer’s disease, she adds. The works shows a potential explanation for how abnormal tau proteins accumulate in the brain, she adds. Tau proteins usually help to support the internal structure of cells and make them stronger, including cells in the brain. But in people with Alzheimer’s disease, the protein stops working properly. Brodtmann says tau then becomes “sticky”, forming clumps in the cells and causing them to die. These tau tangles tend to accumulate in regions of the brain that are involved in memory. © 2026 Springer Nature Limited

Keyword: Alzheimers; Glia
Link ID: 30152 - Posted: 03.07.2026

By Jake Currie Struggling to remember a forgotten memory is an all-too-common frustration—one that unfortunately becomes more common as we age. We realize that there’s something we can’t recall, but we simply can’t raise it from the depths of our brains. So where did it go? New research published in the Journal of Neuroscience suggests these memories are still lurking in our minds, even though we think they’re long gone. Subscribe to skip ads Featured Video Psychologists from the University of Nottingham led by Benjamin Griffiths strapped participants into a magnetoencephalography machine to measure the magnetic fields surrounding the electrical activity in their brains. Participants were asked to vividly associate a short video clip with a word, and when they were later shown that word, they were asked to recall the video clip while psychologists monitored the magnetic activity of their brains. They found that the brain reactivated memories whether they were consciously recalled or not, meaning the memories were there. When memories were successfully recalled, the reactivated memory signal fluctuated rhythmically in the alpha band. Alpha brain waves, research has shown, are associated with the memorization of visual information, but it was the rhythmicity of the waves that proved key to conscious recall. “What we showed is that even when the brain can reactivate the right memory, it doesn’t guarantee you’ll become aware of it,” Griffiths explained. “Instead, what seems to matter is that the memory rhythmically pulses so that it can be detected above and beyond other neural activity.”

Keyword: Learning & Memory; Brain imaging
Link ID: 30151 - Posted: 03.07.2026

Denis Campbell Weight loss drugs could help people avoid getting addicted to alcohol, tobacco and drugs such as cannabis and cocaine, a study has found. They could also reduce the risk of people already addicted to illicit substances having an overdose, ending up in hospital or dying, according to research published in the British Medical Journal. Glucagon-like peptide-1 receptor agonists used to treat type 2 diabetes and obesity, such as Mounjaro and Ozempic, are thought to work by influencing the brain’s reward pathways in order to cut cravings. They help people feel fuller by mimicking the natural substance released after eating. The US study analysed 606,434 US veterans with type 2 diabetes, who were monitored for up to three years. It found that GLP-1s reduced the risk of alcohol-related disorders in those with no history of substance use by 18% and of using cannabis (14%), cocaine (20%), nicotine (20%) and opioids (25%), compared with those on other sodium-glucose cotransporter-2 drugs also used to treat diabetes. Weight loss drugs also reduce the risk of people already using substances from overdosing (39%), needing emergency help in A&E (31%) or dying (50%). “This study adds to emerging research exploring whether GLP-1 medicines may influence brain pathways involved in reward and addiction”, said Prof Claire Anderson, the president of the Royal Pharmaceutical Society, which represents 35,500 UK pharmacists. She added: “As this was an observational study, it is important to be clear that it does not show these medicines prevent or treat addiction. Further research, including clinical trials, will be needed to understand whether GLP-1 medicines have a direct effect.” © 2026 Guardian News & Media Limited

Keyword: Drug Abuse; Obesity
Link ID: 30150 - Posted: 03.07.2026

By Helena Kudiabor Two neurobiologists who helped decipher how the somatosensory system detects touch and pain have won this year’s Brain Prize, the world’s largest award in neuroscience. Patrik Ernfors, professor of tissue biology at the Karolinska Institutet, and David Ginty, professor of neurobiology at Harvard University, will share the 10 million Danish kroner (about $1.6 million) prize. The award was announced today by the Lundbeck Foundation, which founded the Brain Prize in 2011. The honorees will be officially awarded at a ceremony in Copenhagen in May. Research by Ernfors and Ginty has “created a blueprint for understanding normal touch and for pinpointing where things go wrong in disorders such as chronic pain,” said Andreas Meyer-Lindenberg, chair of the Brain Prize selection committee, in a press release announcing the winners. Ernfors was honored for his contributions to classifying the neurons that make up the sensory nervous system in mice. Historically, neuroscientists differentiated among different somatosensory neurons based on a handful of functional features, such as conduction velocity, individual markers and cell morphology, Ernfors says. He and his colleagues have instead classified different types of neurons based on the constellation of genes they express. For example, in one of his most-cited analyses, Ernfors and his colleagues distinguished 622 mouse sensory neurons based on their gene expression patterns. “Now that we know what kinds of neurons there are, we can establish where they project peripherally, centrally, how they connect to each other and what makes them active or inactive,” Ernfors explains. © 2026 Simons Foundation

Keyword: Pain & Touch
Link ID: 30149 - Posted: 03.07.2026

By Christina Caron On the latest season of the HBO Max hospital drama “The Pitt,” a law student named Jackson arrived in the emergency room in a state of psychosis after he “flipped out in the library” and threw a chair at a campus security guard. The news that he might have a mental illness comes as a shock to Jackson’s family, but it soon becomes clear that his break with reality didn’t come out of nowhere. Jackson has been hearing voices for months, viewers learn: “They don’t want me to pass the bar,” he says. “That’s what they told me.” It’s often assumed that psychosis symptoms such as auditory hallucinations and paranoid delusions appear out of the blue. But in reality, most patients with a first episode of psychosis have experienced milder symptoms for months or even years. What’s important, experts say, is recognizing and addressing those symptoms early. “I always tell people if I broke my leg today and got it treated today, it would heal much better than if I waited 18 months,” said Nicholas J. K. Breitborde, director of the Early Psychosis Intervention Center at the Ohio State University Wexner Medical Center. Psychosis is a disruption of the mind’s thoughts and perceptions that causes someone to lose contact with reality. People with psychosis might hear voices, as Jackson did, or see things that other people don’t. They may also have difficulty thinking clearly and may harbor false beliefs, for example the idea that other people are trying to hurt them. Other symptoms include incoherent speech and inappropriate behavior © 2026 The New York Times Company

Keyword: Schizophrenia
Link ID: 30148 - Posted: 03.07.2026

Jon Hamilton A human brain consumes less power than a light bulb, while artificial intelligence systems guzzle electricity to do the same tasks. Now, scientists have created a highly efficient AI model that hints at how living brains are able to do so much with so little, a team reports in the journal Nature. Light enters the compound eye of the fly, causing the photoreceptors to send electrical signals through a complex neural network, enabling the fly to detect motion The model, which mimics a part of the brain's visual system, started out using 60 million variables. But the team was able to compress it into a version that performed nearly as well using just 10,000 variables. "That is incredibly small," says Ben Cowley, an author of the study and an assistant professor at Cold Spring Harbor Laboratory. "This is something we could send in a tweet or an email." The compact model also appears to work more like a living brain, which could help scientists study what goes wrong in diseases like Alzheimer's, Cowley says. More broadly, if the AI model really does replicate strategies found in nature, it could help scientists understand the inner workings of human brains, says Mitya Chklovskii, a group leader at the Simons Foundation's Flatiron Institute, who was not involved in the study. Compact, biology-inspired models of the brain could also lead to "more powerful and more humanlike artificial intelligence," says Chklovskii, who is also on the faculty at NYU. © 2026 npr

Keyword: Robotics; Vision
Link ID: 30147 - Posted: 03.04.2026

By Nick Hilden Since the start of the so-called psychedelic renaissance some 25 years ago, writers have tackled the subject from the vantages of science, politics, mental health, productivity, creativity, spirituality, how-to, and even cooking. With his new book On Drugs, Justin Smith-Ruiu explores these powerful drugs through a philosophical lens, analyzing their effects and implications via thinkers spanning Foucault to Freud, Spinoza to Sartre, and scores of others who over the past 2,000 years have sought to explain the mysteries of the human experience. While authors have applied philosophy to psychedelics before, they have typically done so through the framework of mental health or otherwise medicinal frameworks, while Smith-Ruiu is more interested in treating psychedelics as philosophical objects worthy of examination in and of themselves. At the same time, he follows the drugs down the rabbit hole, sizing up what psychedelics taught him on a personal level, and delving into questions surrounding the scientific prohibition of auto-experimentation, whether the hallucinations conjured by psychedelics are real or imagined, and what they have to teach us about the nature of reality. A professor of history and science, Smith-Ruiu has previously applied philosophical analysis to some of the most pressing issues of our day. In The Internet Is Not What You Think It Is, he explored how the internet arose from some of our deepest philosophical yearnings. In Irrationality, he asserted that human irritation is fundamental to the human experience rather than a contextual social aberration. And in Nature, Human Nature, and Human Difference, he argued that our contemporary conceptions of race are not innate but rather emerged from the modern scientific efforts to classify and systematize. (He also happens to have an asteroid named after him—it doesn’t get much “higher” than that.) © 2026 NautilusNext Inc.,

Keyword: Drug Abuse; Consciousness
Link ID: 30146 - Posted: 03.04.2026

By Bethany Brookshire When solving a puzzle, the answer could lie in your dreams. In a study of lucid dreamers, playing soundtracks linked with unsolved puzzles helped the sleepers solve the problems the next day, researchers report February 5 in Neuroscience of Consciousness. Stories of brilliant insights after a nap or daydream abound, but scientists have struggled to successfully influence people’s dreams and rigorously test the idea. “This study provides one of the first experimentally grounded demonstrations of such a link,” says Giulio Bernardi, a cognitive neuroscientist at IMT School for Advanced Studies Lucca, in Italy, who was not involved with the work. Whether we remember our dreams or not, we have countless dreams in our sleep, according to Karen Konkoly, a cognitive neuroscientist who performed the study at Northwestern University in Evanston, Ill. “Your dreams are such a big part of your inner life,” she says. And in the right circumstances, manipulating those dreams could help people think of problems in new ways. While some scientists have shown that sleeping on a problem increases the odds of solving it the next day, others have shown no benefit. Of course, it might help only if you actually think about the problem in your sleep. Konkoly and her colleagues were especially interested in helping sleepers think about specific topics using targeted memory reactivation, or TMR. “It’s this research technique where you have a sensory stimuli that’s associated with a memory,” Konkoly says. “It could be a very soft sound or a smell that’s presented to a sleeper, and it functions to remind the sleeping brain of the full memory.” While people dream in every stage of sleep, the effects of TMR have been strongest in deep, slow-wave sleep, she says. Konkoly wanted to look at the effects of TMR at a different sleep stage — rapid eye movement sleep, which could be helpful for creative thinking. © Society for Science & the Public 2000–2026.

Keyword: Sleep; Learning & Memory
Link ID: 30145 - Posted: 03.04.2026

By Dana G. Smith Many people’s brains deteriorate as they age, becoming riddled with malfunctioning proteins that result in cell death and the loss of memory and cognition. But other people’s brains remain almost perfectly intact, their thinking as sharp at 80 as it was in their 50s. A paper published Wednesday in the journal Nature provides a new potential explanation for this discrepancy, and it taps into one of the hottest debates in neuroscience: whether human brains can grow new neurons in adulthood, a phenomenon called neurogenesis. The study found that so-called super-agers — people 80 and up who have the memory ability of someone 30 years younger — had roughly twice as many new neurons as older adults with normal memory for their age, and 2.5 times more than people with Alzheimer’s disease. The research focused on an area of the brain called the hippocampus, which is important for learning and memory and is thought to be the primary birthplace of new neurons. “This paper shows biological proof that the aging brain is plastic,” even into a person’s 80s, said Tamar Gefen, an associate professor of psychiatry and behavioral sciences at the Northwestern University Feinberg School of Medicine, who contributed to the research. To look for neurogenesis in older adults, the scientists first tried to detect signs of it in the autopsied brains of young adults, age 20 to 40, who died with normal cognition. They identified genetic markers for three key types of cells: neural stem cells, neuroblasts and immature neurons. © 2026 The New York Times Company

Keyword: Neurogenesis; Alzheimers
Link ID: 30144 - Posted: 02.28.2026

Mariana Lenharo Adults whose brains still have strong neuron production seem to have better memory and cognitive function than do those in whom the ability wanes, finds a study published today in Nature1. The authors examined brain samples from deceased donors ranging from young adults to ‘super agers’ — people older than 80 with exceptional memory. She lived to 117: what her genes and lifestyle tell us about longevity They found that young and old adults with healthy cognition generated neurons, a process called neurogenesis, at high levels for their age. The team estimated that the new neurons made up only a small fraction — 0.01% — of those in the hippocampus, a brain region that’s essential for memory. By contrast, in people experiencing cognitive decline, including individuals with Alzheimer’s disease, neurogenesis seems to falter: the researchers spotted fewer developing, or immature, neurons in those brain samples. Surprisingly, a group of ‘super agers’ had an even higher number of immature neurons than did other groups, and significantly more than did those with Alzheimer’s. However, the group sizes were small, so the findings were not all statistically significant. Maura Boldrini Dupont, a neuroscientist and psychiatrist at Columbia University in New York City, says that the small size of the groups — each had ten or fewer individuals — is a reason to take the results with a grain of salt. Understanding the tools that the brain uses to generate neurons and maintain cognitive function in old age could help researchers to develop drugs that induce neurogenesis in people with cognitive decline, says co-author Orly Lazarov, a neuroscientist at the University of Illinois Chicago. © 2026 Springer Nature Limited

Keyword: Neurogenesis; Alzheimers
Link ID: 30143 - Posted: 02.28.2026

By Tim Vernimmen Steve Fleming’s research is definitely “meta” — a Greek prefix indicating self-reference. He’s a cognitive neuroscientist at University College London who studies metacognition: what we know about what we know, think about what we think, believe about what we believe. While this may seem quite philosophical and well-nigh impossible to study in the lab, he has made it his mission to measure and model it and understand where in the brain it manifests itself. Fleming explored these issues in his 2021 book, Know Thyself: The Science of Self-Awareness. In the 2024 Annual Review of Psychology, he further examined the link between metacognition and confidence: our sense of whether we have made the right decision, whether we are successful at the tasks presented to us, and whether our worldview is likely correct. Fleming’s work is casting new light on why some people seem chronically underconfident even when they’re doing just fine, and why others are entirely convinced they’re right about everything, even when there is overwhelming evidence to the contrary. In the following discussion, which has been edited for length and clarity, Fleming shared his thoughts on some of the questions that inevitably come up when our brains assess their own activity. Metacognition is quite an uncommon research topic. How did you end up studying this? I studied experimental psychology in Oxford, where I had the opportunity to work with psychologist Paul Azzopardi. He studies blindsight, a condition where, due to certain types of brain damage, people are subjectively blind but still able to perform various tasks using visual information. This presents a fascinating dissociation between conscious experience and actual functionality.

Keyword: Consciousness; Attention
Link ID: 30142 - Posted: 02.28.2026

By Nora Belblidia To the naked eye, Annie Kathuria’s experiments look a bit like tiny tufts of cotton floating in pink Petri dishes. These unassuming orbs are clusters of millions of human brain cells called brain organoids — brainstem organoids in this case — cultured in a lab in East Baltimore. Roughly a month old, the tufts are each around a millimeter wide, smaller than a coarse grain of salt. “We have about maybe 500 to 600 organoids growing,” said Kathuria, an assistant professor of biomedical engineering and neurosurgery at Johns Hopkins University. In addition to the brainstem organoids, her lab is also growing other types that correspond to different parts of the nervous system: cortical organoids, which mimic a brain’s developing cortex, and spinal cord organoids, to model the spinal nerve tissue that connects to the brain. Each of these clumps of neural tissue functions similarly to specific regions of the human brain. That similarity has led to some media coverage referring to them as “mini-brains” or “brains in a dish” — now irksome terms to many researchers in the field, some of whom also prefer the term neural organoids to brain organoids. Annie Kathuria, assistant professor of biomedical engineering and neurosurgery, in her lab at Johns Hopkins University in Baltimore. Visual: Nora Belblidia for Undark “Whatever else they are, they aren’t brains. They aren’t organized like brains. They aren’t big enough,” said Hank Greely, a Stanford University professor and expert in law and biosciences who works with researchers in the field. “But more importantly, they don’t have the right architecture.” By that he means organoids are basic parts of a whole, similar to how a broom closet or stairwell would never be considered a skyscraper.

Keyword: Development of the Brain
Link ID: 30141 - Posted: 02.28.2026

By Justin O’Hare For decades, two complementary but often siloed approaches have guided neuroscience: cellular neuroscience, which seeks to understand how individual neurons work; and systems neuroscience, which aims to uncover how networks of neurons coordinate to produce thoughts, movements and behaviors. One studies the tree; the other studies the forest. Each approach has produced tremendous advances. For instance, cellular neuroscientists have revealed how ion channels shape the electrical language of the brain, how synapses strengthen or weaken with experience and how gene expression governs neuronal function. Meanwhile, systems neuroscientists have mapped entire circuits, recorded the activity of tens of thousands of neurons during behavior and identified patterns of activity that correlate with memory, decision-making and emotion. But for all these advances, a question lingers: Are we actually any closer to understanding how the brain works? The jaw-dropping datasets produced by systems-level studies are seldom reconciled with biology, and the exquisite detail uncovered by cellular-level studies is rarely extrapolated from circuits to behavior. These disconnects don’t reflect failures of either approach. Rather, they reflect the vast intellectual and material resources that each requires. Nevertheless, the brain is a multiscale organ. It is organized across multiple hierarchical levels operating in concert, not in parallel. To unravel the brain’s deepest complexities, we need to bridge cellular and systems neuroscience. Because of recent technological advances in high-density electrical probes, genetically encoded fluorescent sensors, multiphoton imaging and high-performance computing, we are better suited to do this now than ever before. © 2026 Simons Foundation

Keyword: Learning & Memory; Brain imaging
Link ID: 30140 - Posted: 02.28.2026

Rachel Fieldhouse Alzheimer’s disease is about to become a big problem for China. Nearly 30% of all people with the condition or related forms of dementia already live in the country. And with its ageing population and falling birth rate, the burden on health and social welfare is expected to multiply dramatically in the coming decades. The Chinese government has responded with programmes and funding that are aimed at improving screening, diagnosis and treatment of Alzheimer’s disease by 2030. And the research has started to take off. Scientists have been working on new drugs and innovative — if controversial — surgical techniques. The government has also encouraged the development of drugs derived from traditional Chinese medicine. And researchers are accelerating the search for biological markers that precede the onset of Alzheimer’s disease, including genetic contributors, which could explain how the condition develops and reveal the best way to identify it early. Although the investments don’t yet match the level of funding in the United States, the improving quality and quickening pace of clinical and preclinical research has attracted attention from researchers around the world. “Maybe China is the next place that will take the lead,” says John Hardy, a neurogeneticist at the UK Dementia Research Institute in London, who is also affiliated with the Hong Kong Center for Neurodegenerative Diseases. Treating the root of the problem Nearly 17 million people in China had Alzheimer’s disease and related dementias in 2021 — about 9 in 1,000, according to a report published last year1. Projections suggest that this number could reach as high as 66 million by 2050 (see ‘Dementia’s rise’) or even exceed 100 million by then2,3. The problem is compounded by China’s low fertility rate, which means that there will be fewer people of working age to support the growing population of older individuals with debilitating conditions. © 2026 Springer Nature Limited

Keyword: Alzheimers
Link ID: 30139 - Posted: 02.25.2026

By Carl Zimmer Look at just about any vertebrate and you’ll see two eyes looking back at you. Falcons circling overhead have two eyes, just like hammerhead sharks roving through the ocean. Scientists have long puzzled over how the vertebrate eye first evolved. A pair of new studies suggest a strange beginning: Our invertebrate ancestors 560 million years ago were cyclopes, with a single eye at the top of their head, scientists now propose, that only later split in two. Charles Darwin fretted a lot about the exquisite complexity and sophistication of the vertebrate eye as he developed his theory of evolution. “The eye to this day gives me a cold shudder,” he confided to his friend, the American botanist Asa Gray, in 1860. Somehow evolution had produced the eye from many parts, such as the lens and retina, through tiny changes through the generations. Darwin couldn’t say for sure what that sequence of changes was. But he was encouraged by the diversity of simpler eyes among invertebrates. Some are mere lumps of pigment that detect light; others are simple cups lacking lenses. “When I think of the fine known gradations,” Darwin wrote to Gray, “my reason tells me I ought to conquer the cold shudder.” Yet opponents of evolution continued to cast doubt on the idea that eyes could evolve. Even in the 1990s, creationists claimed that natural selection would need many billions of years to produce an eye — far more time than life has existed on Earth. Dan-E. Nilsson, a neurobiologist at Lund University in Sweden, grew so annoyed by these claims that he estimated how long it would actually take for a patch of light-sensitive cells to evolve into an image-forming eye. “I thought, Heck, that’s an easy calculation, let’s do that,” Dr. Nilsson recalled. In 1994 he and Susanne Pelger, a colleague at Lund, concluded that an image-forming eye could evolve in just a few hundred thousand years. “It’s not precise in any way at all, but it goes to show that there is plenty of time for eyes to evolve,” Dr. Nilsson said. © 2026 The New York Times Company

Keyword: Evolution
Link ID: 30138 - Posted: 02.25.2026

By Hannah Thomasy In 1774, British physician-scientist Charles Blagden received an unusual invitation from a fellow physician: to spend time in a small room that was hotter, he wrote, “than it was formerly thought any living creature could bear.” Many people may have been appalled by this offer, but Blagden was delighted by the opportunity for self-experimentation. He marveled as his own temperature remained at 98 degrees Fahrenheit (approximately 37 degrees Celsius), even as the temperature of the room approached 200°F (about 93°C). Today, this ability to maintain a stable body temperature — called homeothermy — is known to exist among myriad species of mammals and birds. But there are also some notable exceptions. The body temperature of the fat-tailed dwarf lemur, for example, can fluctuate by nearly 45°F (25°C) over a single day. In fact, a growing body of research suggests that many more animals than scientists once appreciated employ this flexible approach — heterothermy — varying their body temperature for minutes, hours or weeks at a time. This may help the animals to persist through all sorts of dangers. “Because we’re homeotherms, we assume all mammals work the way we do,” says Danielle Levesque, a mammalian ecophysiologist at the University of Maine. But in recent years, as improvements in technology allowed researchers to more easily track small animals and their metabolisms in the wild, “we’re starting to find a lot more weirdness,” she says. The most extreme — and well-known — form of heterothermy is classic hibernation, which has been most extensively studied in critters who use it to save energy and so survive the long, cold winters of the Northern Hemisphere. These animals enter long periods of what scientists call deep torpor, when metabolism slows to a crawl and body temperature can drop to just above freezing.

Keyword: Evolution
Link ID: 30137 - Posted: 02.25.2026

By Emma Gometz Caribou, large deer that are native to the northernmost parts of the world (and sometimes called reindeer), are the only deer whose females grow antlers. In a study published today, researchers observed behavior that might explain why: female caribou appear to gnaw on shed antlers as a kind of postbirthing supplement. Caribou migrate huge distances every year between the places where they graze during the winter and the grounds where they calve in the spring. They can walk thousands of miles per year and likely have the longest terrestrial migration of any animal. Caribou mothers complete these extremely long migrations with antlers on their head and a calf in their womb. The period is very nutritionally demanding for them but culminates with a reserve stock of supplements when they need it the most. The researchers behind the new study figured this out when they observed bite marks in more than 80 percent of the 1,500 caribou antlers that littered the part of the Arctic National Wildlife Refuge in northeastern Alaska where the deer give birth. “[Caribou] are just really going after the antlers. They are highly selective,” says study co-author Joshua Miller, a paleoecologist at the University of Cincinnati. Female caribou shed their antlers just days before giving birth. Miller and co-author Madison Gaetano, a conservation paleobiologist, say that the findings suggest that female caribou are essentially banking nutrients in the form of antlers before they give birth and then gnawing on their freshly shed antlers to get a boost of protein, calcium and phosphorus they need to make up for having less time to graze as they nurse their calves. © 2025 SCIENTIFIC AMERICAN,

Keyword: Sexual Behavior
Link ID: 30136 - Posted: 02.25.2026

By Delthia Ricks Susan E. Leeman, who helped reshape scientific understanding of how the brain sends chemical signals throughout the body, did not hesitate to leave the laboratory when her research demanded it — even if it meant visiting slaughterhouses. In the late 1960s, while running a small lab at Brandeis University, she was trying to isolate a stress hormone and needed large quantities of the bovine hypothalamus, a cow’s version of the structure found deep in all mammalian brains. When supplies ran short at a local meatpacker in Boston, Dr. Leeman traveled to Chicago, home at the time to the sprawling Union Stock Yards, to secure fresh tissue. What ultimately emerged was not the hormone that she sought but an elusive chemical called Substance P. Discovered decades earlier but never fully understood, it was finally identified by Dr. Leeman in 1970 as a neuropeptide, released by cells in the brain or spinal cord in response to pain. Three years later, she identified another neuropeptide. The two discoveries established her as a leading figure in neuroendocrinology. Dr. Leeman died on Jan. 20 in Manhattan, at the home of her daughter Eve Leeman, where she had been living. She was 95. Her death was confirmed by another daughter, Jennifer Leeman. Although Substance P was identified in 1931 by Ulf von Euler and John Gaddum, researchers working in London, it was Dr. Leeman who discovered that it was a neuropeptide — a tiny, protein-like molecule released by neurons, or nerve cells in the brain and spinal cord, that transmits signals to target tissues. It was the first neuropeptide discovered in what would become a large class known as tachykinins. Dr. Leeman found that Substance P relays pain signals and amplifies the sensation of pain by triggering inflammation. It has since been linked to chronic pain syndromes, arthritis pain and migraines. © 2026 The New York Times Company

Keyword: Pain & Touch
Link ID: 30135 - Posted: 02.25.2026

By Katherine Ellison For most of her adult life, Katherine Sanders had what she calls a typical career for someone with attention deficit hyperactivity disorder. After finishing her doctoral thesis on Bronze Age Syrian mythology, she bounced between unrelated jobs. She tutored university students. She sewed Victorian corsets for bridal outfits. She designed stained glass and sold picture frames. She enjoyed the work, but none of it felt like a calling. Life got harder when she found herself juggling part-time work with caring for a spirited five-year-old. Sanders, who lives in Edinburgh, Scotland, burned meals on the stove and forgot to pick up her daughter from school. Finally, she decided to work with a coach to help her cope with her ADHD, a bedeviling condition whose hallmark symptoms are distraction, forgetfulness, restlessness and impulsivity. She began by enrolling in a digital course called Your ADHD Brain is A-OK. Like most ADHD coaches, Tracy Otsuka, the course producer, has herself been diagnosed with the disorder. Otsuka, based in Northern California, says she focuses on helping her clients shed shame as a prelude to finding their purpose and living more fulfilled lives. Participants in the self-paced course watch 26 videos and fill out worksheets designed to identify their values and strengths. Sanders says working with Otsuka led to a lightbulb moment for her. “This woman is very smart, she’s very savvy,” she says. “And she still did stuff like forget to pick her kid up from school.… She still does the same things as me.” The experience made Sanders realize that she, too, was smart but had a specific challenge she needed to learn to manage.

Keyword: ADHD
Link ID: 30134 - Posted: 02.21.2026