By Allison Parshall Until half a billion years ago, life on Earth was slow. The seas were home to single-celled microbes and largely stationary soft-bodied creatures. But at the dawn of the Cambrian era, some 540 million years ago, everything exploded. Bodies diversified in all directions, and many organisms developed appendages that let them move quickly around their environment. These ecosystems became competitive places full of predators and prey. And our branch of the tree of life evolved an incredible structure to navigate it all: the brain. We don’t know whether this was the moment when consciousness first arose on Earth. But it might have been when living creatures began to really need something like it to combine a barrage of sensory information into one unified experience that could guide their actions. It’s because of this ability to experience that, eventually, we began to feel pain and pleasure. Eventually, we became guided not just by base needs but by curiosity, emotions and introspection. Over time we became aware of ourselves. This last step is what we have to thank for most of art, science and philosophy—and the millennia-long quest to understand consciousness itself. This state of awareness of ourselves and our environment comes with many mysteries. Why does being awake and alive, being yourself, feel like anything at all, and where does this singular sense of awareness come from in the brain? These questions may have objective answers, but because they are about private, subjective experiences that can’t be directly measured, they exist at the very boundaries of what the scientific method can reveal. Still, in the past 30 years neuroscientists scouring the brain for the so-called neural correlates of consciousness have learned a lot. Their search has revealed constellations of brain networks whose connections help to explain what happens when we lose consciousness. We now have troves of data and working theories, some with mind-bending implications. We have tools to help us detect consciousness in people with brain injuries. But we still don’t have easy answers—researchers can’t even agree on what consciousness is, let alone how best to reveal its secrets. The past few years have seen accusations of pseudoscience, results that challenge leading theories, and the uneasy feeling of a field at a crossroads. © 2025 SCIENTIFIC AMERICAN,

Keyword: Consciousness; Brain imaging
Link ID: 30090 - Posted: 01.21.2026

By Pria Anand I loved literature before I loved medicine, and as a medical student, I often found that my textbooks left me cold, their medical jargon somehow missing the point of profound diseases able to rewrite a person’s life and identity. I was born, I decided, a century too late: I found the stories I craved, not in contemporary textbooks, but in outdated case reports, 18th- and 19-century descriptions of how the diseases I was studying might shape the life of a single patient. These reports were alive with vivid details: how someone’s vision loss affected their golf game or their smoking habit, their work or their love life. They were all tragedies: Each ended with an autopsy, a patient’s brain dissected to discover where, exactly, the problem lay, to inch closer to an understanding of the geography of the soul. To write these case studies, neurologists awaited the deaths and brains of living patients, robbing their subjects of the ability to choose what would become of their own bodies—the ability to write the endings of their own stories—after they had already been sapped of agency by their illnesses. Among these case reports was one from a forbidding state hospital in the north of Moscow: the story of a 19th-century Russian journalist referred to simply as “a learned man.” The journalist suffered a type of alcoholic dementia because of the brandy he often drank to cure his writer’s block and he developed a profound amnesia. He could not remember where he was or why. He could win a game of checkers but would forget that he had even played the minute the game ended. In the place of these lost memories, the journalist’s imagination spun elaborate narratives; he believed he had written an article when in fact he had barely begun to conceive it before he became sick, would describe the prior day’s visit to a far-off place when in actuality he had been too weak to get out of bed, and maintained that some of his possessions—kept in a hospital safe—had been taken from him as part of an elaborate heist. Sacks’ journals suggest he injected his own experiences into the stories of his patients. © 2026 NautilusNext Inc.,

Keyword: Attention; Learning & Memory
Link ID: 30089 - Posted: 01.21.2026

By Erin Garcia de Jesús A deck brush can be a good tool for the right task. Just ask Veronika, the Brown Swiss cow. Veronika uses both ends of a deck brush to scratch various parts of her body, researchers report January 19 in Current Biology. It’s the first reported tool use in a cow, a species that is often “cognitively underestimated,” the researchers say. Cows usually rub against trees, rocks or wooden planks to scratch, but Veronika’s handy tool allows her to reach parts of her body that she couldn’t otherwise, says Antonio Osuna-Mascaró, a cognitive biologist at the Messerli Research Institute of the University of Veterinary Medicine, Vienna. It’s unclear how the cow figured it out, but “somehow Veronika learned to use tools, and she’s doing something that other cows simply can’t.” Veronika, a pet cow that lives in a pasture on a small Austrian farm, picks up the brush by its handle with her tongue and twists her neck to place the brush where she needs it. Setting the brush in front of her in different orientations showed that she uses the hard, bristled end to target most areas, including the tough, thick skin on her back. She also uses the nonbristled end, slowly moving the handle over softer body parts such as her belly button and udder. Veronika uses different parts of a deck brush to reach various parts of her body. She uses the brush end to scratch large areas such as her thigh (top left) and back (top right). She uses the handle to scratch more delicate areas such as her navel flap (bottom left) and anus (bottom right). © Society for Science & the Public 2000–2026.

Keyword: Learning & Memory; Evolution
Link ID: 30088 - Posted: 01.21.2026

By Ellen Barry and Pam Belluck Emily Sliwinski got home from the hospital after giving birth to her first child three years ago, and almost immediately began spiraling. Her thoughts raced; she was unable to sleep; she began hallucinating that her dog was speaking to her. She became obsessed with solving the national shortage of infant formula, covering a corkboard with notes and ideas. About a week later, Ms. Sliwinski, of Greensboro, N.C., went to a hospital emergency room, thinking she would be given medication to help her sleep, she said. She had no history of mental health issues. When doctors decided to commit her for inpatient psychiatric treatment, she became so agitated and fearful that she slapped her mother and her husband. She spent 11 days in the psychiatric hospital, but it didn’t help. “Every day I was trying to figure out where I was and what was happening,” Ms. Sliwinski, 33, recalled. Doctors there did not connect her symptoms to childbirth, she said, and diagnosed her with schizophrenia. It was only when her family got her transferred to a specialized perinatal psychiatric unit at the University of North Carolina at Chapel Hill that doctors zeroed in on the right diagnosis: postpartum psychosis. Ms. Sliwinski’s delayed diagnosis reflects an issue simmering in the highest echelons of American psychiatry. For more than five years, a group of women’s health specialists have been pushing for postpartum psychosis to be listed as a distinct diagnosis in the Diagnostic and Statistical Manual of Mental Disorders, the thousand-page guidebook that influences research funding, medical training and clinical care. But two committees at the apex of the D.S.M. have been split over whether to add it. “Psychiatry’s Bible,” as it is sometimes known, has raised the evidentiary bar for including new diagnoses — only one, prolonged grief syndrome, has been added since 2013. © 2026 The New York Times Company

Keyword: Depression; Hormones & Behavior
Link ID: 30087 - Posted: 01.21.2026

By Kristen French In 1998, neuroscientist Christof Koch bet philosopher David Chalmers that within 25 years, scientists would discover the neural correlates of consciousness. He was certain that we were on the cusp of solving the so-called hard problem: how the physical flesh of the brain gives way to the everyday streams of feelings, sensations, and thoughts that make up our waking experience. Nautilus Members enjoy an ad-free experience. Log in or Join now . That bet didn’t go well for Koch: A couple of years ago, he paid up, delivering a case of fine wine to his opponent on a conference stage in New York City. But many scientists still believe that the scientific keys to the kingdom of consciousness are within reach. Lately, some are focusing their attention on a new technology called transcranial focused ultrasound, in which acoustic waves are transmitted through the skull deep into the interior tissues. These waves can be used to stimulate specific target areas as small as a few millimeters in size and to monitor the changes that result. Now, two researchers from MIT have mapped out specific ways to use the technology to chip away at the hard problem. Because transcranial focused ultrasound offers a powerful and noninvasive way to alter brain activity, it will allow scientists to track cause-and-effect for the first time, they argue. In a new paper, published in Neuroscience and Biobehavioral Reviews, they plot out a series of experiments that will aim to answer how consciousness arises in the brain—and where. “Transcranial focused ultrasound will let you stimulate different parts of the brain in healthy subjects, in ways you just couldn’t before,” Daniel Freeman, an MIT researcher and co-author of the paper, explained in a statement. “This is a tool that’s not just useful for medicine or even basic science, but could also help address the hard problem of consciousness. It can probe where in the brain are the neural circuits that generate a sense of pain, a sense of vision, or even something as complex as human thought.” © 2026 NautilusNext Inc.,

Keyword: Consciousness
Link ID: 30086 - Posted: 01.17.2026

By Azeen Ghorayshi A scientific review of 43 studies on acetaminophen use during pregnancy concluded that there was no evidence that the painkiller increased the risk of autism or other neurodevelopmental disorders. “We found no clinically important increase in the risk of autism, A.D.H.D. or intellectual disability,” Dr. Asma Khalil, a professor of obstetrics and maternal fetal medicine at St. George’s Hospital, University of London, and the lead author of the report, said at a news briefing. The study was published on Friday in the British medical journal The Lancet. Acetaminophen, the active ingredient in Tylenol, remains “the first-line treatment that we would recommend if the pregnant women have pain or fever in pregnancy,” Dr. Khalil said. Studies that have examined a possible link between acetaminophen in pregnancy and a risk of neurodevelopmental disorders have produced conflicting data, with some finding no connection and others finding small increases in risk. The new review comes after President Trump told pregnant women during a news conference in September to “tough it out” and “fight like hell” not to take Tylenol, because he said the painkiller could cause autism in children. The message was delivered as part of a broader campaign by Health Secretary Robert F. Kennedy Jr. to try to identify the causes behind rising autism rates among children in the United States, zeroing in on the unproven risks of acetaminophen and long-discredited theories that vaccines cause autism. Medical groups worldwide, including the American College of Obstetricians and Gynecologists, quickly disputed the president’s statements. They argued that doctors already advised their pregnant patients to use acetaminophen judiciously, and cautioned that untreated fevers during pregnancy could cause health problems for the mother and the baby © 2026 The New York Times Company

Keyword: Autism
Link ID: 30085 - Posted: 01.17.2026

By Angie Voyles Askham More than 200 published studies and at least seven ongoing clinical trials rely on potentially faulty brain network maps, according to a study published today in Nature Neuroscience. The findings cast doubt on a widely used method to generate brain network maps, says František Váša, senior lecturer in machine learning and computational neuroscience at King’s College London, who was not involved in the new study and has not used the approach in his own work. “I think it’s worth revisiting some of the literature critically,” he says. And for those who use the method or plan to, “proceed with caution,” he adds. The creators of the method, called lesion network mapping (LNM), say that the issues raised by the new study are not insurmountable. The study’s “results are often striking and tell an important cautionary point—that lesion network mapping can be prone to false-positive findings or nonspecific findings, and study designs need to be constructed carefully in a way that can account for this,” wrote LNM co-developer Aaron Boes, professor of pediatrics at the University of Iowa’s Carver College of Medicine, in an email to The Transmitter. Boes and his colleagues developed LNM in 2015 to identify the pattern of brain activity disrupted in a given neurological condition, whether obsessive-compulsive disorder, Parkinson’s disease or psychopathy. It spawned a new way to put functional MRI to practical use, offering a clear brain network to target for treatment, says Martijn van den Heuvel, professor of computational neuroimaging and brain systems at Vrije Universiteit Amsterdam and an investigator on the new study. © 2026 Simons Foundation

Keyword: Brain imaging
Link ID: 30084 - Posted: 01.17.2026

By Darren Incorvaia Much like his ninja namesake, Naruto the white-lipped peccary was a bit of a loner. Named after the titular character from a popular manga and anime, Naruto was the youngest male and one of the least social in his group of 17 peccaries, all of whom were born and raised in captivity at the Laboratory of Applied Ethology at the State University of Santa Cruz in Ilhéus, Brazil. Destined for reintroduction into Brazil’s Estação Veracel Private Natural Heritage Reserve and the Pau-Brasil Ecological Station, the peccaries were each given a personality test of sorts by lab researchers. The piglike mammals were video recorded as they went about their daily lives, resulting in 17 hours’ worth of behavioral data. Their aggressive actions, friendly touches and moments of exploration were tallied so that the peccaries could be ranked in traits such as boldness and sociability. The goal was to determine whether an individual peccary’s behavioral traits influenced its survival when released into the wild. White-lipped peccaries (Tayassu pecari) are listed as vulnerable by the International Union for Conservation of Nature, or IUCN. In Brazil, the size of the species’ historical range had plunged by 60 percent by 2020, and past efforts to reintroduce them had met limited success. Around the globe, scientists are increasingly recognizing how a reintroduced animal’s personality can impact how both individuals and groups fare in the wild. Such work is part of a growing trend to infuse the study of personality, and how it affects behavior, into conservation. When working with wild animals and tight budgets, personality tests may not always be possible. But understanding animal personality could help conservationists choose which individuals stand the best chance of surviving — helping to restore populations threatened with extinction. © Society for Science & the Public 2000–2026.

Keyword: Emotions; Evolution
Link ID: 30083 - Posted: 01.17.2026

Andee Tagle He couldn't stop fixating on it. "I started getting into the frame of mind most people get sucked into. I worried, 'What's going on? Is there something wrong with me?'" he says. That fear of not being able to sleep is a phenomenon called "sleep anxiety," says Orma, who went on to become a specialist in insomnia treatment. Left untreated, that anxiety can prevent people from actually falling asleep. "The more you focus on it, the less chance you'll sleep, which then makes you more anxious. That's the cycle that spins," he says. One of the most powerful ways to overcome sleep anxiety is cognitive behavioral therapy for insomnia (CBT-I). It's well studied, doesn't rely on sleep drugs and has been shown to be effective for clinical insomnia. Orma used this treatment to heal his sleep, and it's now the main focus of his therapy practice. Typically, a CBT-I program lasts about six to eight weeks, and each week, you and a provider work on a strategy to reset sleep behaviors and restructure your thinking around rest. But you don't have to be in an official program to benefit from CBT-I. Whether you're dealing with some sleep stress or just the occasional off-night, these CBT-I practices can help. Wake up at the same time every day Having a consistent wake-up time helps your body know when it's time to get sleepy, says Aric Prather, a sleep scientist and the author of The Sleep Prescription: 7 Days to Unlocking Your Best Rest. The sleepy cues are managed by your circadian rhythm, or your body's internal clock. A set wake-up time keeps your internal clock ticking on time. © 2026 npr

Keyword: Sleep
Link ID: 30082 - Posted: 01.17.2026

By Andrew Jacobs In the billion-dollar race to commercialize psychedelic medicine, psilocybin, a naturally occurring hallucinogen better known as magic mushrooms, or “shrooms,” has decisively pulled ahead of the pack. The Food and Drug Administration in November said it would move up its review of a psilocybin treatment for severe depression by nine to 12 months, according to the applicant, Compass Pathways. It hopes to receive the agency’s approval for the therapy before the end of the year. The news is among the first concrete signs that the Trump administration is recognizing psychedelic medicine as a potential therapy tool. The moves have injected a fresh dose of optimism into a nascent field, which was rattled by the F.D.A.’s rejection in 2024 of MDMA-assisted therapy, the first psychedelic to reach a formal review by federal regulators. “Between research results and policy changes, it’s a watershed moment for psychedelic health care, and psilocybin is the star,” said Nate Howard, director of operations at InnerTrek, a psilocybin clinic in Portland, Ore. Mr. Howard was a driving force behind a successful ballot measure in 2023 that created Oregon’s psilocybin program. State lawmakers, however, are not waiting for regulators in the nation’s capital. Last year, New Mexico joined Colorado and Oregon in offering legal psilocybin therapy to adults. Lawmakers in a dozen states, including North Carolina, Maryland, Georgia and California, are considering easing restrictions on the drug using public funds to research the potential benefits of psilocybin therapy. © 2026 The New York Times Company

Keyword: Depression; Drug Abuse
Link ID: 30081 - Posted: 01.14.2026

Nicola Davis Science correspondent Same-sex sexual behaviour among non-human primates may arise as a way to reinforce bonds and keep societies together in the face of environmental or social challenges, researchers have suggested. Prof Vincent Savolainen, a co-author of the paper from Imperial College London, added that while the work focused on our living evolutionary cousins, early human species probably experienced similar challenges, raising the likelihood they, too, showed such behaviour. “There were many different species that unfortunately [are] all gone, that must have done this same thing as we see in apes, for example,” he said. Writing in the journal Nature Ecology & Evolution, Savolainen and colleagues reported how they analysed accounts of same-sex sexual behaviour in non-human primates, finding it to be widespread in most major groups, with reports in 59 species including chimpanzees, Barbary macaques and mountain gorillas. That, they added, either suggested an evolutionary origin far back in the primate family tree, or the independent evolution of the behaviour multiple times. While some studies have previously highlighted the possibility such behaviour could help reduce tensions in groups or aid bonding, the new study looked across different species to explore its possible drivers. The results reveal it to be more likely in species living in drier environments, where resources are scarce, and where there is greater risk from predators. “Previous research has shown there is a heritable element to [same-sex sexual behaviour], however, there is also environmental influence which is often overlooked,” said Chloe Coxshall, the first author of the study. © 2026 Guardian News & Media Limited

Keyword: Sexual Behavior; Evolution
Link ID: 30080 - Posted: 01.14.2026

Lynne Peeples Sometimes the hardest part of doing an unpleasant task is simply getting started — typing the first word of a long report, lifting a dirty dish on the top of an overfilled sink or removing clothes from an unused exercise machine. The obstacle isn’t necessarily a lack of interest in completing a task, but the brain’s resistance to taking the first step. Now, scientists might have identified the neural circuit behind this resistance, and a way to ease it. In a study1 published today in Current Biology, researchers describe a pathway in the brain that seems to act as a ‘motivation brake’, dampening the drive to begin a task. When the team selectively suppressed this circuit in macaque monkeys, goal-directed behaviour rebounded. “The change after this modulation was dramatic,” says study co-author Ken-ichi Amemori, a neuroscientist at Kyoto University in Japan. The motivation brake, which can be particularly stubborn for people with certain psychiatric conditions, such as schizophrenia and major depressive disorder, is distinct from the avoidance of tasks driven by risk aversion in anxiety disorders. Pearl Chiu, a computational psychiatrist at Virginia Tech in Roanoke, who was not involved in the study, says that understanding this difference is essential for developing new treatments and refining current ones. “Being able to restore motivation, that’s especially exciting,” she says. Motivated macaques Previous work on task initiation has implicated a neural circuit connecting two parts of the brain known as the ventral striatum and ventral pallidum, both of which are involved in processing motivation and reward2,3,4. But attempts to isolate the circuit’s role have fallen short. Electrical stimulation, for example, inadvertently activates downstream regions, affecting motivation, but also anxiety. © 2026 Springer Nature Limited

Keyword: Learning & Memory; Emotions
Link ID: 30079 - Posted: 01.14.2026

By Sujata Gupta Chimps ages 2 to 5 are more likely than older chimps to free-fall from tree limbs in the forest canopies or leap wildly from branch to branch, researchers report January 7 in iScience. Past age 5, those dangerous canopy behaviors decrease by roughly 3 percent each year. Among humans, teens are the real daredevils. They are, for instance, more likely than other children to break bones and die from injuries. But human toddlers might behave as recklessly as chimp toddlers were it not for parents and caregivers putting the kibosh on all the fun — and broken bones, says biologist Lauren Sarringhaus of James Madison University in Harrisonburg, Va. “If humans scaled back their oversight, our kids would be way more daredevilish.” Humans and chimpanzees show markedly different caregiving patterns, say Sarringhaus and others. Chimp moms largely parent alone. Dads don’t help. Nor, typically, do grandmothers, older siblings or other group members. Chimpanzees cling to their moms for the first five years of life, but by age 2 or so, they begin to explore more independently. Moms can’t readily help kids swinging high up in the air. By comparison, the presence of alloparents, or caregivers beyond the parents, are a defining feature of human groups, Sarringhaus says. In modern times, alloparents have come to include teachers and coaches for a plethora of supervised after-school activities. Nowadays, many developmental experts in the Western world have been decrying the rise of intensive or helicopter parenting in which kids spend less time unsupervised and playing outside than those in generations past. “It’s a really exciting avenue of research of how caregiving influences risk-taking behavior. There’s not a lot of research out there addressing this point,” says Lou Haux, a psychologist and primatologist at the Max Planck Institute for Human Development in Berlin, who was not involved with the study. © Society for Science & the Public 2000–2026

Keyword: Development of the Brain; Evolution
Link ID: 30078 - Posted: 01.14.2026

Allison Aubrey If you feel a lift after exercise, you're in good company. Movement can boost mood, and according to the results of a new study, it can also help relieve symptoms of depression. As part of a review of evidence by the Cochrane collaboration — an independent network of researchers — scientists evaluated 73 randomized controlled trials that included about 5,000 people with depression, many of whom also tried antidepressant medication. "We found that exercise was as effective as pharmacological treatments or psychological therapies as well," says Andrew Clegg, a professor at the University of Lancashire in the U.K. The findings are not a surprise to psychiatrist Dr. Stephen Mateka, medical director of psychiatry at Inspira Health. "This new Cochrane review reinforces the evidence that exercise is one of the most evidence-based tools for improving mood," says Mateka. He explains how it mirrors some of the effects of medication. "Exercise can help improve neurotransmitter function, like serotonin as well as dopamine and endorphins. So there is certainly overlap between exercise and how antidepressants offer relief," Mateka says. And there's another powerful effect too. Exercise can trigger the release of brain growth factors, explains Dr. Nicholas Fabiano of the University of Ottawa. He says depression can decrease neuroplasticity, making it harder for the brain to adapt and change. "The brain in depression is thought to be less plastic. So there's less what we call neurotrophic factors, or BDNF," Fabiano explains. He calls it the Miracle-Gro for the brain. "And we know that exercise can also boost it. So I think exercise is a fundamental pillar we really need to counsel patients on," he says. © 2026 npr

Keyword: Depression
Link ID: 30077 - Posted: 01.14.2026

By Azeen Ghorayshi Academic research labs across the country are working to find biological markers that can predict whether a child is at risk of developing autism. And companies are rushing to turn the findings into commercial tests, despite limited evidence to back their validity, raising concerns that their results could mislead desperate parents. They include one test that examines a strand of hair to rule out an autism diagnosis in babies as young as one month old. Two other tests just entered the market. One promises to predict autism risk based on skin cells collected as early as days after birth. Another looks for the presence of certain antibodies in a mother’s blood to determine whether her children, or babies that she might have in the future, are at risk of developing autism. For decades, clinicians and parents have hoped for a biological test that could help determine if a child has autism. The push to commercialize investigators’ early research has accelerated as Health Secretary Robert F. Kennedy Jr. has elevated the neurodevelopmental disorder into a national political priority, creating new funding for autism research and reviving long-discredited theories about autism and vaccines. But the new tests, largely aimed as a screening tool for the general population, are not yet reliable enough to be offered commercially, outside scientists familiar with the tests say, especially in a landscape where families are already inundated with incorrect or unverified information about autism. None of the tests has gone through large experimental trials or had its validity evaluated by a regulatory agency. “All of these tests are interesting hypotheses,” said Joseph Buxbaum, a neuroscientist at the Icahn School of Medicine at Mount Sinai who studies the genetics of autism. But they are “absolutely not at a point for any kind of clinical use,” he said. © 2026 The New York Times Company

Keyword: Autism
Link ID: 30076 - Posted: 01.10.2026

Nell Greenfieldboyce If you've ever had to spell out words like W-A-L-K or T-R-E-A-T around a dog, you know that some dogs listen in to humans' chitchat and can pick out certain key words. Well, it turns out that some genius dogs can learn a brand new word, like the name of an unfamiliar toy, by just overhearing brief interactions between two people. Your dog is a good boy, but that's not necessarily because of its breed Animals Your dog is a good boy, but that's not necessarily because of its breed What's more, these "gifted" dogs can learn the name of a new toy even if they first hear this word when the toy is out of sight — as long as their favorite human is looking at the spot where the toy is hidden. That's according to a new study in the journal Science. "What we found in this study is that the dogs are using social communication. They're using these social cues to understand what the owners are talking about," says cognitive scientist Shany Dror of Eötvös Loránd University and the University of Veterinary Medicine, Vienna. Sponsor Message "This tells us that the ability to use social information is actually something that humans probably had before they had language," she says, "and language was kind of hitchhiking on these social abilities." Fetch the ball — or the frisbee? © 2026 npr

Keyword: Language; Evolution
Link ID: 30075 - Posted: 01.10.2026

Ian Sample Science editor New therapies for Alzheimer’s disease should target a particular gene linked to the condition, according to researchers who said most cases would never arise if its harmful effects were neutralised. The call to action follows the arrival of the first wave of drugs that aim to treat Alzheimer’s patients by removing toxic proteins from the brain. While the drugs slow the disease down, the benefits are minor, and they have been rejected for widespread use by the UK’s National Institute for Health and Care Excellence (Nice). In searching for alternative therapies, scientists at UCL say drug developers should focus on two risk-raising variants of a gene named Apoe. Therapies designed to block the variants’ impact have “vast potential” for preventing the disease, they claim. Dr Dylan Williams, a genetic epidemiologist at UCL, said: “Most Alzheimer’s disease cases would not arise without the contribution of just this single gene: Apoe. We need to think about it as a direct target. Almost all potential Alzheimer’s cases could benefit from Apoe-related interventions.” More than half a million people in the UK, and more than 40 million worldwide, are living with Alzheimer’s disease, the most common form of dementia. Several genes contribute to Alzheimer’s risk and lifestyle is important too: smoking, obesity, diabetes, high blood pressure and cholesterol all make the disease more likely. Williams and his colleagues analysed medical records from more than 450,000 people of European ancestry to calculate how much Alzheimer’s disease arose due to different variants of the Apoe gene. People inherit two copies of the gene – one from each parent – and there are three main variants: Apoe2, 3 and 4. © 2026 Guardian News & Media Limited

Keyword: Alzheimers; Genes & Behavior
Link ID: 30074 - Posted: 01.10.2026

By Natalia Mesa Nestled in the ventromedial nucleus of the hypothalamus lies a cluster of neurons that can make otherwise mild-mannered mice fly into a rage. Stimulating these neurons, as if flipping a switch, prompts male mice to attack their cagemates. The optogenetic manipulation of these and other specialized hypothalamic neurons, starting in the early 2010s, supported the long-standing idea that distinct cell types act as an “on” switch for different innate behaviors. But it has proved challenging to disentangle the neural signals that underlie those innate behaviors from ones that drive an animal’s internal state—such as anger, hunger or sexual arousal. Mounting evidence suggests that the hypothalamus also gives rise to these internal states, which can shape innate perceptions and behaviors. Rather than triggering an innate behavior, a specific pattern of population activity encodes the intensity and duration of anger and sexual arousal, according to four studies published within the past three years. This work is “revolutionary for the hypothalamus community,” says Tatiana Engel, associate professor of computational neuroscience at the Princeton Neuroscience Institute, who was not involved in the studies. It upends the notion that the neurons in the hypothalamus merely act as a simple switchboard, Engel says. Instead, local computations in the hypothalamus keep track of the animal’s internal state and influence its behavior, the studies suggest. The hypothalamic signals that encode the intensity and duration of aggression and sexual arousal can be represented by a mathematical model called a line attractor, the four studies show. © 2026 Simons Foundation

Keyword: Emotions; Evolution
Link ID: 30073 - Posted: 01.10.2026

By Sachin Rawat One can spend hours looking at a calm sunset or a clear night sky. These scenes are not only effortless on the eyes — they may also be easy on the brain. People tend to like visual stimuli that require little cognitive effort to process, researchers report in the December PNAS Nexus. The brain is the most energy-guzzling organ in the body, and visual processing alone accounts for nearly half of its energy use. Researchers have long studied how the visual system conserves energy. But the new study addresses the question from a different perspective. “Not only is the visual system optimized for efficiency, but we might have aesthetic preferences for stimuli that are efficient to process,” says Mick Bonner, a neuroscientist at Johns Hopkins University who was not involved in the study. Neuroscientist Dirk Bernhardt-Walther of the University of Toronto and his colleagues suspected that such preferences could have evolved as cognitive shortcuts, helping organisms avoid excessive effort as they navigate their environment. To probe the energy consumed in visual processing, the researchers turned to an existing functional MRI dataset, in which four individuals viewed 5,000 images while their brain activity was monitored. Measurements of oxygen consumption in different parts of the brain provided an indicator of metabolic activity. The team also ran these images through an artificial neural network trained on object and scene recognition, using the proportion of activated “neurons” as a proxy for metabolic expense. The researchers then compared these metabolic cost estimates — both human and artificial — to the images’ aesthetic ratings, gathered from more than 1,000 online survey respondents who scored each picture on a five-point scale. In both cases, the metabolic effort required to process the images was inversely proportional to their aesthetic ratings. © Society for Science & the Public 2000–2026.

Keyword: Vision; Emotions
Link ID: 30072 - Posted: 01.10.2026

By Carl Zimmer If you live in the United States, chances are you’re familiar with the game rock-paper-scissors. You put out your hand in one of three gestures: clenching it in a fist (rock), holding it out flat (paper) or holding up two fingers in a “V” (scissors). Rock beats scissors, scissors beat paper and paper beats rock. Americans by no means have a monopoly on the game. People play it around the world in many variations, and under many names. In Japan, where the game has existed for thousands of years, it’s known as janken. In Indonesia, it’s known as earwig-man-elephant: The elephant kills the man, the man kills the earwig and the earwig crawls up through the elephant’s trunk and eats its brain. The game is so common that it exists beyond our own species. Over millions of years, animals have evolved their own version of rock-paper-scissors. For them, winning the game means passing down their genes to future generations. A study published on Thursday in the journal Science reveals the hidden biology that makes the game possible — and shows how it may be an important source of nature’s diversity. The first clues that nature also played rock-paper-scissors emerged three decades ago in the dry hills outside Merced, Calif. Barry Sinervo, a biologist then at Indiana University, studied the common side-blotched lizard there. He would mark the lizards — named for the dark blue or black spot on their side, just behind the front leg — release them into the tall grass and catch the survivors to check up on them in later years. Dr. Sinervo, who later joined the faculty at the University of California, Santa Cruz, and who died in 2021, grew fascinated by the strange mating habits of the lizards. At the start of every breeding season, the males developed one of three colors on their throats: blue, orange or yellow. And depending on their color, the males behaved differently. © 2026 The New York Times Company

Keyword: Aggression; Animal Communication
Link ID: 30071 - Posted: 01.07.2026