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

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

By Lauren Schneider Microglia may be a key mediator between maternal immune activation and a pup’s memory of contextual fear conditioning in early infancy, a new mouse study reports. The findings sharpen the picture of memory formation in early life, but the study’s approach to microglia has raised questions. That scrutiny comes as scientists reevaluate concepts such as synaptic pruning, through which microglia may shape neuronal circuits in early life and beyond. Humans and rodents are unable to recall some of the earliest memories formed after birth. This period of infantile amnesia offers researchers a window to test conditions that may alter the survival of engrams, the changes in the brain tied to memory formation. “Development is an experiment that nature does for you,” says study investigator Tomás Ryan, professor in neuroscience at Trinity College Dublin. Activation of the immune system during pregnancy in mice leads to autism-like behaviors in their pups and reduces infantile amnesia, according to a previous study by Ryan’s team. Blocking microglial activity allows some infantile memories to persist in mice, Ryan and his colleagues report in the new paper, published 20 January in PLOS Biology. Administering minocycline in water daily starting one day before foot-shock conditioning at postnatal day 17 led to greater fear memory at postnatal day 25, after the typical onset of infantile amnesia. This recall was accompanied by a reactivation of associated engrams in the basolateral amygdala and central amygdalar nucleus. © 2026 Simons Foundation

Keyword: Glia; Development of the Brain
Link ID: 30122 - Posted: 02.14.2026

Rachael Seidler Tianyi (Erik) Wang Going to space is harsh on the human body, and as a new study from our research team finds, the brain shifts upward and backward and deforms inside the skull after spaceflight. The extent of these changes was greater for those who spent longer in space. As NASA plans longer space missions, and space travel expands beyond professional astronauts, these findings will become more relevant. Why it matters On Earth, gravity constantly pulls fluids in your body and your brain toward the center of the Earth. In space, that force disappears. Body fluids shift toward the head, which gives astronauts a puffy face. Under normal gravity, the brain, cerebrospinal fluid and surrounding tissues reach a stable balance. In microgravity, that balance changes. Without gravity pulling downward, the brain floats in the skull and experiences various forces from the surrounding soft tissues and the skull itself. Earlier studies showed that the brain appears higher in the skull after spaceflight. But most of those studies focused on average or whole brain measures, which can hide important effects within different areas of the brain. Our goal was to look more closely. Astronauts need to exercise and take care of their bodies while in space. We analyzed brain MRI scans from 26 astronauts who spent different lengths of time in space, from a few weeks to over a year. To focus on the brain’s movement, we aligned each person’s skull across scans taken before and after spaceflight. One great story in your inbox every afternoon © 2010–2026, The Conversation US, Inc.

Keyword: Biomechanics
Link ID: 30119 - Posted: 02.14.2026

By Amber Dance Real estate agents will tell you that a home’s most important feature is “location, location, location.” It’s similar in neuroscience: “Location is everything in the brain,” said Bosiljka Tasic (opens a new tab), a self-described “biological cartographer.” Brain injury in one spot could knock out memory; damage in another could interfere with personality. Neuroscientists and doctors are lost without a good map. Researchers have been mapping the brain for more than a century. By tracing cellular patterns that are visible under a microscope, they’ve created colorful charts and models that delineate regions and have been able to associate them with functions. In recent years, they’ve added vastly greater detail: They can now go cell by cell and define each one by its internal genetic activity. But no matter how carefully they slice and how deeply they analyze, their maps of the brain seem incomplete, muddled, inconsistent. For example, some large brain regions have been linked to many different tasks; scientists suspect that they should be subdivided into smaller regions, each with its own job. So far, mapping these cellular neighborhoods from enormous genetic datasets has been both a challenge and a chore. Recently, Tasic, a neuroscientist and genomicist at the Allen Institute for Brain Science, and her collaborators recruited artificial intelligence for the sorting and mapmaking effort. They fed genetic data from five mouse brains — 10.4 million individual cells with hundreds of genes per cell — into a custom machine learning algorithm. The program delivered maps that are a neuro-realtor’s dream, with known and novel subdivisions within larger brain regions. Humans couldn’t delineate such borders in several lifetimes, but the algorithm did it in hours. The authors published their methods (opens a new tab) in Nature Communications in October. © 2026 Simons Foundation

Keyword: Brain imaging; Development of the Brain
Link ID: 30117 - Posted: 02.11.2026

By Ingrid Wickelgren The human brain is a vast network of billions of neurons. By exchanging signals to depress or excite each other, they generate patterns that ripple across the brain up to 1,000 times per second. For more than a century, that dizzyingly complex neuronal code was thought to be the sole arbiter of perception, thought, emotion, and behavior, as well as related health conditions. If you wanted to understand the brain, you turned to the study of neurons: neuroscience. But a recent body of work from several labs, published as a trio of papers in Science in 2025, provides the strongest evidence yet that a narrow focus on neurons is woefully insufficient for understanding how the brain works. The experiments, in mice, zebra fish, and fruit flies, reveal that the large brain cells called astrocytes serve as supervisors. Once viewed as mere support cells for neurons, astrocytes are now thought to help tune brain circuits and thereby control overall brain state or mood — say, our level of alertness, anxiousness, or apathy. Astrocytes, which outnumber neurons in many brain regions, have complex and varied shapes, and sometimes tendrils, that can envelop hundreds of thousands or millions of synapses, the junctions where neurons exchange molecular signals. This anatomical arrangement perfectly positions astrocytes to affect information flow, though whether or how they alter activity at synapses has long been controversial, in part because the mechanisms of potential interactions weren’t fully understood. In revealing how astrocytes temper synaptic conversations, the new studies make astrocytes’ influence impossible to ignore. “We live in the age of connectomics, where everyone loves to say [that] if you understand the connections [between neurons], we can understand how the brain works. That’s not true,” said Marc Freeman (opens a new tab), the director of the Vollum Institute, an independent neuroscience research center at Oregon Health and Science University, who led one of the new studies. “You can get dramatic changes in firing patterns of neurons with zero changes in [neuronal] connectivity.” © 2026 Simons Foundation

Keyword: Glia; Learning & Memory
Link ID: 30103 - Posted: 01.31.2026

By Claudia López Lloreda The U.S. Brain Research through Advancing Innovative Neurotechnologies (BRAIN) Initiative is kicking off a new phase. In a road map published in November, it identified four research priorities for the next decade: integrating its databases, informing precision circuit therapies, understanding human neuroscience and advancing NeuroAI. The plan shows a thoughtful effort to “protect a very important initiative,” says J. Anthony Movshon, professor of neural science and psychology at New York University—at a time when its future seems unsettled. The BRAIN Initiative is co-led by the directors of the National Institute of Mental Health and the National Institute for Neurological Disorders and Stroke. But the NIMH has had an acting director since June 2024. Last month, the Trump administration terminated the initiative’s other co-director—Walter Koroshetz—from his role as director of the National Institute for Neurological Disorders and Stroke. And it is not clear whether the initiative will have sufficient funding or support to undertake this decade-long effort, says Joshua Sanes, professor emeritus of molecular and cellular biology at Harvard University and contributing editor for The Transmitter. “My guess is that if things continue politically the way they’re going now, [these goals] would not be accomplished in the United States in the next 10 years.” Even if the BRAIN Initiative receives the amount of funding it is expecting, many neuroscientists are too busy grappling with the fallout of grant cancellations, hiring freezes and the loss of training programs to think about the future, says Eve Marder, university professor of biology at Brandeis University. “I’m talking to all these people who are struggling to keep their labs open.” “You can have all the dreams in the universe,” but these big-picture speculations, which may require vast resources, are hard to reconcile with the erosion and destruction of academic science and training programs for young investigators, she adds. “It is difficult to look at a 10-year horizon, and [it] may be a waste of time and effort when we don’t know what is happening to science funding in the next year.” © 2026 Simons Foundation

Keyword: Brain imaging
Link ID: 30093 - Posted: 01.24.2026

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 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

Alison Abbott For decades, neuroscientists focused almost exclusively on only half of the cells in the brain. Neurons were the main players, they thought, and everything else was made up of uninteresting support systems. By the 2010s, memory researcher Inbal Goshen was beginning to question that assumption. She was inspired by innovative molecular tools that would allow her to investigate the contributions of another, more mysterious group of cells called astrocytes. What she discovered about their role in learning and memory excited her even more. At the beginning, she felt like an outsider, especially at conferences. She imagined colleagues thinking, “Oh, that’s the weird one who works on astrocytes,” says Goshen, whose laboratory is at the Hebrew University of Jerusalem. A lot of people were sceptical, she says. But not any more. A rush of studies from labs in many subfields are revealing just how important these cells are in shaping our behaviour, mood and memory. Long thought of as support cells, astrocytes are emerging as key players in health and disease. “Neurons and neural circuits are the main computing units of the brain, but it’s now clear just how much astrocytes shape that computation,” says neurobiologist Nicola Allen at the Salk Institute for Biological Studies in La Jolla, California, who has spent her career researching astrocytes and other non-neuronal cells, collectively called glial cells. “Glial meetings are now consistently oversubscribed.” As far back as the nineteenth century, scientists could see with their simple microscopes that mammalian brains included two major types of cell — neurons and glia — in roughly equal numbers. © 2025 Springer Nature Limited

Keyword: Glia
Link ID: 30038 - Posted: 12.03.2025

By Jennie Erin Smith More than a decade ago, when researchers discovered a ghostly network of microscopic channels that push fluid through the brain, they began to wonder whether the brain’s plumbing, as they sometimes refer to it, might be implicated in neurodegenerative diseases such as Alzheimer’s. Now, they are testing a host of ways to improve it. At the Society for Neuroscience (SfN) meeting last month in San Diego, several teams reported early promise for drugs and other measures that improve fluid flow, showing they can remove toxic proteins from animal or human brains and reverse symptoms in mouse models of neurological disease. Plastic surgeons in China, meanwhile, have gone further, conducting experimental surgeries that they say help flush out disease-related proteins in people with Alzheimer’s. The trials have generated excitement but also concern over their bold claims of success. A group of academic surgeons in the United States is planning what they say will be a more rigorous clinical trial, also in Alzheimer’s patients, that could begin recruiting as early as next year. The surgical approach “sounds unbelievable,” says neuroscientist Jeffrey Iliff of the University of Washington. “But I’m not going to say I know it can’t work. Remember, 13 years ago we didn’t know any of this existed.” In 2012, Iliff, with pioneering Danish neuroscientist Maiken Nedergaard and colleagues, described a previously unrecognized set of fluid channels in the brain that they dubbed the glymphatic system. Three years later, other groups revealed a second, related system of fluid transport: a matrix of tiny lymphatic vessels in the meninges, or membranes covering the brain. © 2025 American Association for the Advancement of Science.

Keyword: Alzheimers
Link ID: 30037 - Posted: 12.03.2025

Hannah Devlin Science correspondent Scientists have identified five major “epochs” of human brain development in one of the most comprehensive studies to date of how neural wiring changes from infancy to old age. The study, based on the brain scans of nearly 4,000 people aged under one to 90, mapped neural connections and how they evolve during our lives. This revealed five broad phases, split up by four pivotal “turning points” in which brain organisation moves on to a different trajectory, at around the ages of nine, 32, 66 and 83 years. “Looking back, many of us feel our lives have been characterised by different phases. It turns out that brains also go through these eras,” said Prof Duncan Astle, a researcher in neuroinformatics at Cambridge University and senior author of the study. “Understanding that the brain’s structural journey is not a question of steady progression, but rather one of a few major turning points, will help us identify when and how its wiring is vulnerable to disruption.” The childhood period of development was found to occur between birth until the age of nine, when it transitions to the adolescent phase – an era that lasts up to the age of 32, on average. In a person’s early 30s the brain’s neural wiring shifts into adult mode – the longest era, lasting more than three decades. A third turning point around the age of 66 marks the start of an “early ageing” phase of brain architecture. Finally, the “late ageing” brain takes shape at around 83 years old. The scientists quantified brain organisation using 12 different measures, including the efficiency of the wiring, how compartmentalised it is and whether the brain relies heavily on central hubs or has a more diffuse connectivity network. From infancy through childhood, our brains are defined by “network consolidation”, as the wealth of synapses – the connectors between neurons – in a baby’s brain are whittled down, with the more active ones surviving. During this period, the study found, the efficiency of the brain’s wiring decreases. © 2025 Guardian News & Media Limited

Keyword: Development of the Brain; Brain imaging
Link ID: 30027 - Posted: 11.26.2025

By Meghan Rosen It sounds like something from a horror movie: A disease that eats through bone, dissolving the fused plates of the skull like bubbling acid. But a type of brain cancer called glioblastoma actually does something similar, triggering the erosion of living skull tissue, researchers report October 3 in Nature Neuroscience. The work shows in gory detail that brain cancer can erode bone, a harmful effect that wasn’t previously known, says Jinan Behnan, a brain tumor immunologist at Albert Einstein College of Medicine in Bronx, New York. Behnan’s findings uncover a creepy new facet of glioblastoma, an enigmatic cancer still cloaked in scientific questions. “We really still don’t understand exactly what this disease is,” she says. Glioblastoma is an aggressive form of brain cancer that’s particularly lethal and nearly impossible to cure. In the United States, doctors diagnose more than 12,000 new cases every year. Five years after diagnosis, only about five percent of patients over 40 years old survive. © Society for Science & the Public 2000–2025

Keyword: Miscellaneous
Link ID: 29982 - Posted: 10.25.2025

By Catherine Offord Neuroscientists have been studying synapses, the fundamental junctions that allow rapid communication between neurons, for well over a century. But now, a research team has identified a different set of neuronal connections in the brain—one that might bypass synapses altogether, the group reports today in Science. Using high-resolution images of mouse and human brains, the researchers documented a network of tubes, each about 3 micrometers long and just a few hundred nanometers thick, connecting neurons to one another. In mouse cells, the team found evidence of neuron-to-neuron transfer of electrical signals via these nanotubes, and even the passage of proteins linked to Alzheimer’s disease. “We’ve been looking at the brain forever now, and every once in a while, a surprise comes along,” says Lary Walker, a neuroscientist and professor emeritus at Emory University who was not involved in the work. Although there’s still a lot to pin down about these nanotubes’ basic biology, he suggests the discovery could have wide implications for scientists’ understanding of neuronal communication and disease. Researchers already knew some cells form nanotubes. In a 2004 Science paper, a team in Germany described tiny channels that emerged spontaneously between rat kidney cells in a dish and allowed the transfer of organelles. Studies since then have documented these so-called tunneling nanotubes (TNT) in a variety of cell and tissue types, and have linked their presence to processes including organ development, tissue repair, and the spread of viruses within the body. Recent research has identified TNTs forming between neurons and microglia, the brain’s immune cells, and hinted that they have important functions in brain health and disease. But scientists have struggled to find such conduits connecting neurons to one another in the mammalian brain. The search is particularly tricky because neurons’ branching ends, or dendrites, form a tangled mass with one another, and because researchers lack molecular markers distinguishing nanotubes from other cell structures. © 2025 American Association for the Advancement of Science.

Keyword: Development of the Brain; Brain imaging
Link ID: 29957 - Posted: 10.04.2025

By Calli McMurray The authors behind a contentious 2022 Science paper that purported to measure neuronal activity using functional MRI (fMRI) retracted the work today. The retraction marks the end of the road for the method, called “direct imaging of neuronal activity,” or DIANA, says Noam Shemesh, principal investigator at the Champalimaud Centre for the Unknown, who was not involved in the now-retracted work. But many neuroimaging researchers still hope to one day use fMRI to capture neuronal activity. “MRI is such a rich modality. It has such rich physics, and not all of it has been exploited in the functional sense,” Shemesh says. DIANA collected fMRI data in a way that enabled the researchers to measure signal changes on the order of tens of milliseconds. The team, led by Jang-Yeon Park at Sungkyunkwan University, captured a signal peak in the somatosensory cortex of mice 25 milliseconds after shocking their whisker pads. Despite an initial flurry of excitement from the field, other labs could not replicate the results. As a result, the paper received an editorial expression of concern in August 2023 because “the methods described in the paper are inadequate to allow reproduction of the results and … the results may have been biased by subjective data selection,” the notice states. Following the editorial expression of concern, “we reanalyzed the data. Unfortunately, the additional results revealed unexpected MR signal characteristics and did not robustly support the original conclusions. We are therefore retracting the paper,” the retraction notice states. Science did not have any additional comment beyond what is outlined in the expression of concern and retraction notice. © 2025 Simons Foundation

Keyword: Brain imaging
Link ID: 29943 - Posted: 09.27.2025

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

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

By Claudia López Lloreda The process of making a decision engages neurons across the entire brain, according to a new mouse dataset created by an international collaboration. “Many, many areas are recruited even for what are arguably rather simple decisions,” says Anne Churchland, professor of neurobiology at University of California, Los Angeles and one of the founding members of the collaboration, called the International Brain Laboratory (IBL). The canonical model suggests that the activity underlying vision-dependent decisions goes from the visual thalamus to the primary visual cortex and association areas, and then possibly to the frontal cortex, Churchland says. But the new findings suggest that “maybe there’s more parallel processing and less of a straightforward circuit than we thought.” Churchland and other scientists established the IBL in 2017 out of frustration with small-scale studies of decision-making that analyzed only one or two brain regions at a time. The IBL aimed to study how the brain integrates information and makes a decision at scale. “We came together as a large group with the realization that a large team effort could be transformative in these questions that had been kind of stymieing all of us,” Churchland says. After years of standardizing their methods and instrumentation across the 12 participating labs, the IBL team constructed a brain-wide map of neural activity in mice as they complete a decision-making task. That map, published today in Nature, reveals that the activity associated with choices and motor actions shows up widely across the brain. The same is true for the activity underlying decisions based on prior knowledge, according to a companion paper by the same team, also published today in Nature. © 2025 Simons Foundation

Keyword: Attention; Brain imaging
Link ID: 29918 - Posted: 09.06.2025

By Claudia López Lloreda fMRI researchers have long faced a conundrum: Given finite resources and time to spend on scanning, is it better to scan lots of participants for a short time each, or a smaller number of people for a longer time? A new study quantifies this tradeoff for brain-wide association studies (BWAS), which aim to link brain differences to physical and cognitive traits. Using large-scale public fMRI datasets, the team found that their ability to accurately predict cognitive features from functional connectivity data increased with sample size and with scan length, up to 20 minutes. But accuracy began to plateau for longer scans, and beyond 30 minutes, the added length (and cost) provided diminishing returns. A half-hour seems to be the optimal scanning time, says Thomas Yeo, associate professor of electrical and computer engineering at the National University of Singapore and principal investigator of the study. Scan duration is “essentially providing a different knob for people to tune” to meet power requirements in their fMRI experiments, he says. Although the neuroimaging community already knew that scan time is important and five minutes is insufficient, “this is one of the first major studies in the past few years to really quantitatively map that out” for BWAS studies, says Brenden Tervo-Clemmens, assistant professor of psychiatry and behavioral sciences at the University of Minnesota, who was not involved with the study. Tervo-Clemmens and his colleagues had previously shown in a 2022 study the importance of sample size in BWAS, calculating that these analyses need thousands of participants to get meaningful associations. This new study adds another part of the equation, he says. Yeo’s team developed the Optimal Scan Time Calculator to help other neuroscientists design their own studies. “Democratizing these complex methodological issues into a usable package is really, really useful,” Tervo-Clemmens says. © 2025 Simons Foundation

Keyword: Brain imaging
Link ID: 29903 - Posted: 08.27.2025

By Lydia Denworth A remarkably bright pulsing dot has appeared on the monitor in front of us. We are watching, in real time, the brain activity of a graduate student named Nick, who is having an afternoon nap inside an imaging machine at the Massachusetts Institute of Technology, where Lewis has her laboratory. The bright spot first appears toward the bottom of the screen, about where Nick’s throat meets his jaw. It moves slowly upward, fades and then is followed by another bright dot. “It really comes and goes,” says Lewis, who is also affiliated with Massachusetts General Hospital. “It’s in waves.” This moving dot depicts something few people have ever seen: fresh cerebrospinal fluid flowing from the spinal cord into the brain, part of a process that researchers are now learning is vital for keeping us healthy. For decades biologists have pondered a basic problem. As human brains whir and wonder throughout the day, they generate waste—excess proteins and other molecules that can be toxic if not removed. Among those proteins are amyloid beta and tau, key drivers of Alzheimer’s disease. Until recently, it was entirely unclear how the brain takes out this potentially neurotoxic trash. In the rest of the body, garbage removal is handled initially by the lymphatic system. Excess fluid and the waste it carries move from tissue into the spleen, lymph nodes and other parts of the system, where certain particles are removed and put into the bloodstream to be excreted. It was long thought that the brain can’t use the same trick, because the so-called blood-brain barrier, a protective border that keeps infections from reaching critical neural circuitry, stops the transport of most everything in and out. © 2025 SCIENTIFIC AMERICAN,

Keyword: Sleep; Neuroimmunology
Link ID: 29895 - Posted: 08.20.2025

By Siddhant Pusdekar The food we eat, the air we breathe, and our daily activities all shape how our minds work. Yet most brain research focuses on a narrow slice of humanity: people in high-income countries in the Northern Hemisphere. That leaves a vast gap in our understanding of how neural activity varies across cultures, environments, and lifestyles. A team of researchers from Tanzania and India has taken a step toward closing that gap. In a study published this week in eNeuro, they describe a strategy for collecting data from the brains of diverse groups—from hunter-gatherers to urban dwellers—using electroencephalography (EEG). The technology relies on portable headsets, widely used in clinical settings, that record the brain’s electrical activity through electrodes placed on the scalp. The researchers trained trusted community members as “surveyors,” who visited participants where they live and work to gather EEG data and conduct surveys about their lifestyles and experiences. The initial effort, which involved nearly 8000 volunteers across Tanzania and India, shows that this kind of data collection in low- and middle-income countries is feasible and affordable, the researchers say. The work cost them $50 for each person studied, a fraction of equivalent, large-scale studies conducted in research labs. A: I think mental health is one of the defining health issues in India. When we survey 18- to 24-year-olds, 50% tell us that almost every other day of the month they don’t feel like going to work or college. India is a young country and is increasingly relying on its youth to grow its economy. If they can’t function in their daily activities, you can’t expect them to be productive and contribute to the economy.

Keyword: Brain imaging
Link ID: 29869 - Posted: 07.26.2025