By Calli McMurray Daniel Heinz clicked through each folder in the file drive, searching for the answers that had evaded him and his lab mates for years. Heinz, a graduate student in Brenda Bloodgood’s lab at the University of California, San Diego (UCSD), was working on a Ph.D. project, part of which built on the work of a postdoctoral researcher who had left the lab and started his own a few years prior. The former postdoc studied how various types of electrical activity in the mouse hippocampus induce a gene called NPAS4 in different ways. One of his discoveries was that, in some situations, NPAS4 was induced in the far-reaching dendrites of neurons. The postdoc’s work resulted in a paper in Cell, landed him more than $1.4 million in grants and an assistant professor position at the University of Utah, and spawned several follow-up projects in the lab. In other words, it was a slam dunk. But no one else in the lab—including Heinz—could replicate the NPAS4 data. Other lab members always had a technical explanation for why the replication experiments failed, so for years the problem was passed from one trainee to another. Which explains why, on this day in early April 2023, Heinz was poking around the postdoc’s raw data. What he eventually found would lead to a retraction, a resignation and a reckoning, but in the moment, Heinz says, he was not thinking about any of those possibilities. In fact, he had told no one he was doing this. He just wanted to figure out why his experiments weren’t working. To visualize the location of NPAS4, the lab used immunohistochemistry, which tags a gene product with a tailored fluorescent antibody. Any part of the cell that expresses the gene should glow. In his replication attempts, Heinz says he struggled to see any expression, and when he saw indications of it, the signal was faint and noisy. So he wanted to compare his own images to the postdoc’s raw results rather than the processed images included in the 2019 Cell paper. © 2024 Simons Foundation

Keyword: Learning & Memory
Link ID: 29504 - Posted: 10.05.2024

By Miryam Naddaf Neurons in the hippocampus help to pick out patterns in the flood of information pouring through the brain.Credit: Arthur Chien/Science Photo Library The human brain is constantly picking up patterns in everyday experiences — and can do so without conscious thought, finds a study1 of neuronal activity in people who had electrodes implanted in their brain tissue for medical reasons. The study shows that neurons in key brain regions combine information on what occurs and when, allowing the brain to pick out the patterns in events as they unfold over time. That helps the brain to predict coming events, the authors say. The work was published today in Nature. “The brain does a lot of things that we are not consciously aware of,” says Edvard Moser, a neuroscientist at the Norwegian University of Science and Technology in Trondheim. “This is no exception.” To make sense of the world around us, the brain must process an onslaught of information on what happens, where it happens and when it happens. The study’s authors wanted to explore how the brain organizes this information over time — a crucial step in learning and memory. The team studied 17 people who had epilepsy and had electrodes implanted in their brains in preparation for surgical treatment. These electrodes allowed the authors to directly capture the activity of individual neurons in multiple brain regions. Among those regions were the hippocampus and entorhinal cortex, which are involved in memory and navigation. These areas contain time and place cells that act as the body’s internal clock and GPS system, encoding time and locations. “All the external world coming into our brain has to be filtered through that system,” says study co-author Itzhak Fried, a neurosurgeon and neuroscientist at the University of California, Los Angeles. © 2024 Springer Nature Limited

Keyword: Attention; Learning & Memory
Link ID: 29497 - Posted: 09.28.2024

Jon Hamilton Aging and Alzheimer's leave the brain starved of energy. Now scientists think they've found a way to aid the brain's metabolism — in mice. PM Images/Getty Images The brain needs a lot of energy — far more than any other organ in the body — to work properly. And aging and Alzheimer’s disease both seem to leave the brain underpowered. But an experimental cancer drug appeared to re-energize the brains of mice that had a form of Alzheimer’s — and even restore their ability to learn and remember. The finding, published in the journal Science, suggests that it may eventually be possible to reverse some symptoms of Alzheimer’s in people, using drugs that boost brain metabolism. The results also offer an approach to treatment that’s unlike anything on the market today. Current drugs for treating Alzheimer’s, such as lecanemab and donanemab, target the sticky amyloid plaques that build up in a patient’s brain. These drugs can remove plaques and slow the disease process, but do not improve memory or thinking. The result should help “change how we think about targeting this disease,” says Shannon Macauley, an associate professor at the University of Kentucky who was not involved in the study. The new research was prompted by a lab experiment that didn’t go as planned. A team at Stanford was studying an enzyme called IDO1 that plays a key role in keeping a cell’s metabolism running properly. They suspected that in Alzheimer’s disease, IDO1 was malfunctioning in a way that limited the brain’s ability to turn nutrients into energy. © 2024 npr

Keyword: Alzheimers; Learning & Memory
Link ID: 29462 - Posted: 09.04.2024

By Rebecca Dzombak Birds can be picky building their nests. They experiment with materials, waffle over which twig to use, take them apart and start again. It’s a complex, fiddly process that can seem to reflect careful thought. “It’s so fascinating,” Maria Tello-Ramos, a behavioral ecologist at the University of St. Andrews in Scotland, said. “But it hasn’t been studied much at all.” New research led by Dr. Tello-Ramos, published on Thursday in the journal Science, provides the first evidence that groups of birds that build their homes together learn to follow consistent architectural styles, distinct from groups just a few dozen feet away. The finding upends longstanding assumptions that nest building is an innate behavior based on the birds’ environment and adds to a growing list of behaviors that make up bird culture. As important for survival as nest building is, scientists know relatively little about it. Most of what is known about bird nests has come from studying their role in reproductive success, focusing on their usefulness in protecting birds and eggs from cold, wind and predators. “The focus has been on the structure, not the behavior that built it,” Dr. Tello-Ramos said. She said she found that surprising because nest building is one of the rare behaviors that has a tangible product, something that can be measured and provide insight into why birds behave the way they do. Part of the reason nest-building behaviors haven’t been researched much, Dr. Tello-Ramos said, boils down to one cliché: bird brain. Nest building is such a complex behavior that, for decades, scientists thought “the little brains of birds couldn’t possibly deal with such a large amount of information, so it must be innate,” she said. Recent work has shown birds repeating others’ nest building, but those studies were often limited to individuals or small groups in labs. © 2024 The New York Times Company

Keyword: Learning & Memory; Evolution
Link ID: 29457 - Posted: 08.31.2024

By Shaena Montanari Mammalian brains famously come with a built-in GPS system: “place cells” in the hippocampus that selectively activate when an animal enters a specific location and power spatial cognition. A comparable navigation system had not been described in fish—until now. As it turns out, zebrafish larvae, too, possess place cells that integrate multiple sources of information and generate new cognitive maps when the animal’s environment changes, according to a study out today in Nature. The search for these cells in fish became “kind of like a myth, almost,” says the study’s co-lead investigator Jennifer Li, research group leader at the Max Planck Institute for Biological Cybernetics. She and her team were hesitant to look for place cells in fish at first, Li says, “because we figured if nobody’s seeing them after all this time,” they might not exist. But Li and her colleagues had already custom-built a microscope that tracks calcium signaling in the brains of zebrafish larvae as they swim freely. The device helped them pinpoint the place cells in the larvae’s telencephalon region. “I think this work is definitely extremely interesting, because it demonstrates that, at least in some fish, you can find place cells,” says Ronen Segev, professor of life sciences at Ben-Gurion University of the Negev, who was not involved in the study. The finding also suggests that spatial cognition has origins deep in the vertebrate evolutionary tree, Li says. There is an idea that the “hippocampus and cortex are these structures that evolved at some point to enable flexible behavior,” but evolutionarily, “it was never clear when that happened.” © 2024 Simons Foundation

Keyword: Learning & Memory; Evolution
Link ID: 29456 - Posted: 08.31.2024

By Greg Donahue In late 2018, after an otherwise-normal Christmas holiday, Laurie Beatty started acting strange. An 81-year-old retired contractor, he grew unnaturally quiet and began poring over old accounting logs from a construction business he sold decades earlier, convinced that he had been bilked in the deal. Listen to this article, read by Robert Petkoff Over the course of several days, Beatty slipped further into unreality. He told his wife the year was 1992 and wondered aloud why his hair had turned white. Then he started having seizures. His arms began to move in uncontrollable jerks and twitches. By the end of May, he was dead. Doctors at the Georges-L.-Dumont University Hospital Center in Moncton, the largest city in the province of New Brunswick, Canada, zeroed in on an exceedingly rare condition — Creutzfeldt-Jakob disease, caused by prions, misfolding proteins in the brain — as the most likely culprit. The doctors explained this to Beatty’s children, Tim and Jill, and said they would run additional tests to confirm the post-mortem diagnosis. Three months later, when the siblings returned to the office of their father’s neurologist, Dr. Alier Marrero, that’s what they were expecting to hear. Instead, Marrero told them that Laurie’s Creutzfeldt-Jakob test had come back negative. “We were all looking at one another,” Tim says, “because we were all very confused.” If Creutzfeldt-Jakob hadn’t killed their father, then what had? What Marrero said next was even more unsettling. “There’s something going on,” they recall him saying. “And I don’t know what it is.” It turned out that Laurie Beatty was just one of many local residents who had gone to Marrero’s office exhibiting similar, inexplicable symptoms of neurological decline — more than 20 in the previous four years. The first signs were often behavioral. One patient fell asleep for nearly 20 hours straight before a friend took her to the hospital; another found himself afraid to disturb the stranger who had sat down in his living room, only to realize hours later that the stranger was his wife. © 2024 The New York Times Company

Keyword: Alzheimers; Learning & Memory
Link ID: 29434 - Posted: 08.15.2024

Andrew Gregory Health editor Almost half of dementia cases worldwide could be prevented or delayed, a study has found, as experts named 14 risk factors. The number of people living with dementia globally is forecast to nearly triple to 153 million by 2050, and researchers warn this presents a rapidly growing threat to health and social care systems. Global health and social costs linked to dementia exceed $1tn (£780bn) a year, the research shows. However, in a seismic report published by the Lancet, 27 of the world’s leading dementia experts concluded that far more cases could be avoided or delayed than previously thought. Addressing 14 modifiable risk factors, starting in childhood and continuing throughout life, could prevent or delay 45% of dementia cases, even as people live longer, the Lancet commission on dementia said. The findings were presented at the Alzheimer’s Association international conference in the US. In an interview with the Guardian, the lead author of the research, Prof Gill Livingston, said it was increasingly clear that there was much more that millions of people could and should do to reduce the risk of dementia. Speaking from the conference in Philadelphia, Livingston said: “Many people around the world believe dementia is inevitable but it’s not. Our report concludes that you can hugely increase the chances of not developing dementia or pushing back its onset. “It’s also important to stress that while we now have stronger evidence that longer exposure to risk has a greater effect … it’s never too early or too late to take action.” © 2024 Guardian News & Media Limited

Keyword: Alzheimers; Learning & Memory
Link ID: 29420 - Posted: 08.03.2024

By Liam Drew In November 2008, neuroscientist Susana Carmona — then a postdoc studying attention deficit hyperactivity disorder — was driving two colleagues to a party when one of them revealed that she was thinking about having a child. The trio became so engulfed in conversation about how pregnancy might change her brain that they diverted from the party and headed to their laboratory to search the literature. They found numerous studies in rodents, but in humans, “there was basically nothing at all”, says Carmona. Shocked by this gap in research, Carmona and her colleagues convinced their mentor at the Autonomous University of Barcelona, Spain, Oscar Vilarroya, to let them run a study using magnetic resonance imaging (MRI) to measure the neuroanatomy of women before they became pregnant, and then again after they gave birth. Squeezed in alongside their main projects, the investigation took eight years and included dozens of participants. The results, published in 2016, were revelatory1. Two to three months after giving birth, multiple regions of the cerebral cortex were, on average, 2% smaller than before conception. And most of them remained smaller two years later. Although shrinkage might evoke the idea of a deficit, the team showed that the degree of cortical reduction predicted the strength of a mother’s attachment to her infant, and proposed that pregnancy prepares the brain for parenthood. Today, Carmona, now at the Gregorio Marañón Health Research Institute in Madrid, is one of several scientists uncovering how pregnancy and parenthood transform the brain. Elseline Hoekzema, one of Carmona’s passengers that evening in 2008, is another. In 2022, Hoekzema, who is now at the Amsterdam University Medical Centre in the Netherlands, confirmed that the cortical regions that shrink during pregnancy also function differently for at least a year after giving birth2. These studies and others, say researchers, highlight a transformational life event that has long been neglected by neuroscience — one that around 140 million women experience annually.

Keyword: Sexual Behavior; Hormones & Behavior
Link ID: 29418 - Posted: 08.02.2024

Jon Hamilton A key protein that helps assemble the brain early in life also appears to protect the organ from Alzheimer’s and other diseases of aging. A trio of studies published in the past year all suggest that the protein Reelin helps maintain thinking and memory in ailing brains, though precisely how it does this remains uncertain. The studies also show that when Reelin levels fall, neurons become more vulnerable. There’s growing evidence that Reelin acts as a “protective factor” in the brain, says Li-Huei Tsai, a professor at MIT and director of the Picower Institute for Learning and Memory. “I think we’re on to something important for Alzheimer’s,” Tsai says. Various pieces of colorful trash, such as plastic bottle caps and plastics forks, are arranged in the shape of a human brain, on a light blue background. The research has inspired efforts to develop a drug that boosts Reelin or helps it function better, as a way to stave off cognitive decline. “You don't have to be a genius to be like, ‘More Reelin, that’s the solution,’” says Dr. Joseph Arboleda-Velasquez of Harvard Medical School and Massachusetts Eye and Ear. “And now we have the tools to do that.” From Colombia, a very special brain Reelin became something of a scientific celebrity in 2023, thanks to a study of a Colombian man who should have developed Alzheimer’s in middle age but didn’t. The man, who worked as a mechanic, was part of a large family that carries a very rare gene variant known as Paisa, a reference to the area around Medellin where it was discovered. Family members who inherit this variant are all but certain to develop Alzheimer’s in middle age. © 2024 npr

Keyword: Alzheimers; Development of the Brain
Link ID: 29413 - Posted: 07.31.2024

By Katie Moisse Monkeys can memorize a sequence of images and then toggle between them in their minds, a new study has found. Each mental move is associated with a tiny burst of brain activity that could be the neural representation of a thought, the study authors say. The study is the first to find evidence that an animal creates cognitive maps based on experience and later uses them exclusively, without any sensory input, to navigate a new task. It also marks one of the first times researchers have registered brain activity tied to an ongoing, complex thought process. “It’s a very fluid process—the process of thinking. And we have no way in animals to know what they’re thinking and therefore map what we record in the brain to what’s happening in the mind,” says study investigator Mehrdad Jazayeri, professor and director of education, brain and cognitive sciences at MIT’s McGovern Institute and a Howard Hughes Medical Institute investigator. In the new study, however, Jazayeri and his team designed a task that requires the animal to imagine a specific scenario at a specific time. “Imagination: There’s no magic to it; it’s a pattern of activity in the brain,” he says. Previous studies suggest rodents use cognitive maps to recreate the past and predict future possibilities. The new study, published last month in Nature, suggests monkeys also engage in such mental simulation and do so in the present—imagining states of the world that they just can’t see. “It’s a little bit like an animal navigating in the dark, where they’re using an internal map of where they are and where they’re going to update their sense of how close they are to their goal,” says Loren Frank, professor of physiology at the University of California, San Francisco, School of Medicine and a Howard Hughes Medical Institute investigator, who was not involved in the work. “Our brains do this all the time. But this study gives us a sense of how they do it and shows there’s an identifiable underlying process. It’s a really nice step forward.” Research image of the activity of a single neuron in a monkey brain. © 2024 Simons Foundation

Keyword: Learning & Memory; Evolution
Link ID: 29412 - Posted: 07.31.2024

By Vivian La Great Basin was burning the midnight oil on a chilly fall evening in 2016 when he made his move. Slinking out of the shadows in Laramie, Wyoming, the raccoon approached what looked like a metal filing cabinet lying on its side. He could smell a mix of dog kibble and sardines within, but 12 latched narrow doors blocked his entry. Making matters worse, a fellow raccoon had beaten him there. So Great Basin jumped on top of the cabinet and began to fiddle with the latches upside down. He quickly opened one of the doors, securing the treats and filling his belly. Humans have long regarded raccoons—renowned for their ability to jimmy their way into locked garbage cans and enter seemingly impassable attics—with a mixture of awe and scorn. But outside of the lab, researchers have little scientific sense of how clever these “trash pandas” really are. A study published today in the Proceedings of the Royal Society B: Biological Sciences may change that. The work was led by Lauren Stanton, a cognitive ecologist at the University of California, Berkeley who has studied raccoons for 10 years. She says she’s drawn by their quirky personalities and quick ability to adapt to environments such as urban areas. “I think it’s fascinating to think about how raccoons perceive the world.” Despite their reputation for cleverness, Stanton says raccoons generally are understudied because they can be “a menace in the lab,” gnawing on cages and biting scientists. Research on wild raccoons is even more scarce. © 2024 American Association for the Advancement of Science.

Keyword: Learning & Memory; Evolution
Link ID: 29406 - Posted: 07.27.2024

By Bianca Nogrady The ability to remember and recognize a musical theme does not seem to be affected by age, unlike many other forms of memory. “You’ll hear anecdotes all the time of how people with severe Alzheimer’s can’t speak, can’t recognize people, but will sing the songs of their childhood or play the piano,” says Sarah Sauvé, a feminist music scientist now at the University of Lincoln in the United Kingdom. Past research has shown that many aspects of memory are affected by ageing, such as recall tasks that require real-time processing, whereas recognition tasks that rely on well-known information and automatic processes are not. The effect of age on the ability to recall music has also been investigated, but Sauvé was interested in exploring this effect in a real-world setting such as a concert. In her study1, published today in PLoS ONE, she tested how well a group of roughly 90 healthy adults, ranging in age from 18 to 86 years, were able to recognize familiar and unfamiliar musical themes at a live concert. Participants were recruited at a performance of the Newfoundland Symphony Orchestra in St John’s, Canada. Another 31 people watched a recording of the concert in a laboratory. The study focused on three pieces of music played at the concert: Eine kleine Nachtmusik by Mozart, which the researchers assumed most participants were familiar with, and two specially commissioned experimental pieces. One of these was tonal and easy to listen to; the other was more atonal and didn’t conform to the typical melodic norms of Western classical music. A short melodic phrase from each of the three pieces was played three times at the beginning of that piece, and participants then logged whenever they recognized that theme in the piece. © 2024 Springer Nature Limited

Keyword: Learning & Memory; Alzheimers
Link ID: 29405 - Posted: 07.27.2024

By Elissa Welle One question long plagued memory researcher André Fenton: How can memories last for years when a protein essential to maintaining them, called memory protein kinase Mzeta (PKMzeta), lasts for just days? The answer, Fenton now says, may lie in PKMzeta’s interaction with another protein, called postsynaptic kidney and brain expressed adaptor protein (KIBRA). Complexes of the two molecules maintain memories in mice for at least one month, according to a new study co-led by Fenton, professor of neural science at New York University. The bond between the two proteins “protects each of them,” Fenton says, from normal degradation in the cell. KIBRA preferentially gloms onto potentiated synapses, the study shows. And it may help PKMzeta stick there, too, where the kinase acts as a “molecular switch” to help memories persist, Fenton says. “As Theseus’ Ship was sustained for generations by continually replacing worn planks with new timbers, long-term memory can be maintained by continual exchange of potentiating molecules at activated synapses,” Fenton and his colleagues write in their paper, which was published last month in Science Advances. Before this study, the PKMzeta mystery had two “missing puzzle pieces,” says Justin O’Hare, assistant professor of pharmacology at the University of Colorado Denver, who was not involved in the study. One was how PKMzeta identifies potentiated synapses, part of the cellular mechanism underlying memory formation. The second was how memories persist despite the short lifetime of each PKMzeta molecule. This study “essentially proposes KIBRA as a solution to both of those—and the experiments themselves are pretty convincing and thorough. They do everything multiple ways.” PKMzeta has been widely studied, but its role in memory has been shrouded in controversy for more than a decade, Fenton says. Although early work suggested that PKMzeta is necessary for memory formation, later studies found that they still form in mice missing the gene for PKMzeta. © 2024 Simons Foundation

Keyword: Learning & Memory
Link ID: 29396 - Posted: 07.18.2024

By Lara Lewington, It's long been known that our lifestyles can help to keep us healthier for longer. Now scientists are asking whether new technology can also help slow down the ageing process of our brains by keeping track of what happens to them as we get older. One sunny morning, 76-year-old Dutch-born Marijke and her husband Tom welcomed me in for breakfast at their home in Loma Linda, an hour east of Los Angeles. Oatmeal, chai seeds, berries, but no processed sugary cereal or coffee were served - a breakfast as pure as Loma Linda’s mission. Loma Linda has been identified as one of the world’s so-called Blue Zones, places where people have lengthier-than-average lifespans. In this case, it is the city’s Seventh-Day Adventist Church community who are living longer. They generally don’t drink alcohol or caffeine, stick to a vegetarian or even vegan diet and consider it a duty of their religion to look after their bodies as best they can. This is their “health message”, as they call it, and it has put them on the map - the city has been the subject of decades of research into why its residents live better for longer. Dr Gary Fraser from the University of Loma Linda told me members of the Seventh-Day Adventist community there can expect not only a longer lifespan, but an increased “healthspan” - that is, time spent in good health - of four to five years extra for women and seven years extra for men. Marijke and Tom had moved to the city later in life, but both were now firmly embedded in the community. Copyright 2024 BBC.

Keyword: Development of the Brain; Learning & Memory
Link ID: 29391 - Posted: 07.13.2024

Anna Bawden The idea that night owls who don’t go to bed until the early hours struggle to get anything done during the day may have to be revised. It turns out that staying up late could be good for our brain power as research suggests that people who identify as night owls could be sharper than those who go to bed early. Researchers led by academics at Imperial College London studied data from the UK Biobank study on more than 26,000 people who had completed intelligence, reasoning, reaction time and memory tests. They then examined how participants’ sleep duration, quality, and chronotype (which determines what time of day we feel most alert and productive) affected brain performance. They found that those who stay up late and those classed as “intermediate” had “superior cognitive function”, while morning larks had the lowest scores. Going to bed late is strongly associated with creative types. Artists, authors and musicians known to be night owls include Henri de Toulouse-Lautrec, James Joyce, Kanye West and Lady Gaga. But while politicians such as Margaret Thatcher, Winston Churchill and Barack Obama famously seemed to thrive on little sleep, the study found that sleep duration is important for brain function, with those getting between seven and nine hours of shut-eye each night performing best in cognitive tests. © 2024 Guardian News & Media Limited

Keyword: Biological Rhythms; Learning & Memory
Link ID: 29389 - Posted: 07.11.2024

By Shaena Montanari Five years ago, while working to develop a tool to label neurons active during seizures in mice, Quynh Anh Nguyen noticed something she had not seen before. “There was a particular region in the brain that seemed to light up really prominently,” she says. Nguyen, assistant professor of pharmacology at Vanderbilt University, had induced seizures in the animals by injecting kainic acid into the hippocampus—a common strategy to model temporal lobe epilepsy. The condition often involves hyperactivity in the anterior and middle regions of the hippocampus, but Nguyen’s mice also showed the activation in a tiny posterior part of the hippocampus that she was not familiar with. Nguyen brought the data to her then-supervisor Ivan Soltesz, professor of neurosciences and neurosurgery at Stanford University. Together they realized that these neurons were in an area called the fasciola cinereum—a subregion of the hippocampus so understudied, Soltesz says, that when Nguyen first asked him what it was, he had “no idea.” Despite the subregion’s obscurity, it looks to be an important and previously overlooked contributor to epilepsy in people who do not respond to anti-seizure medications or tissue ablation in the hippocampus, Nguyen and her colleagues say. Fasciola cinereum neurons were active during seizures in six people with drug-resistant epilepsy, the team reported in April. © 2024 Simons Foundation

Keyword: Epilepsy
Link ID: 29360 - Posted: 06.15.2024

By Max Kozlov A crucial brain signal linked to long-term memory falters in rats when they are deprived of sleep — which might help to explain why poor sleep disrupts memory formation1. Even a night of normal slumber after a poor night’s sleep isn’t enough to fix the brain signal. These results, published today in Nature, suggest that there is a “critical window for memory processing”, says Loren Frank, a neuroscientist at the University of California, San Francisco, who was not involved with the study. “Once you’ve lost it, you’ve lost it.” In time, these findings could lead to targeted treatments to improve memory, says study co-author Kamran Diba, a computational neuroscientist at the University of Michigan Medical School in Ann Arbor. Neurons in the brain seldom act alone; they are highly interconnected and often fire together in a rhythmic or repetitive pattern. One such pattern is the sharp-wave ripple, in which a large group of neurons fire with extreme synchrony, then a second large group of neurons does the same and so on, one after the other at a particular tempo. These ripples occur in a brain area called the hippocampus, which is key to memory formation. The patterns are thought to facilitate communication with the neocortex, where long-term memories are later stored. One clue to their function is that some of these ripples are accelerated re-runs of brain-activity patterns that occurred during past events. For example, when an animal visits a particular spot in its cage, a specific group of neurons in the hippocampus fires in unison, creating a neural representation of that location. Later, these same neurons might participate in sharp-wave ripples — as if they were rapidly replaying snippets of that experience. © 2024 Springer Nature Limited

Keyword: Learning & Memory; Sleep
Link ID: 29358 - Posted: 06.13.2024

By Yasemin Saplakoglu György Buzsáki first started tinkering with waves when he was in high school. In his childhood home in Hungary, he built a radio receiver, tuned it to various electromagnetic frequencies and used a radio transmitter to chat with strangers from the Faroe Islands to Jordan. He remembers some of these conversations from his “ham radio” days better than others, just as you remember only some experiences from your past. Now, as a professor of neuroscience at New York University, Buzsáki has moved on from radio waves to brain waves to ask: How does the brain decide what to remember? By studying electrical patterns in the brain, Buzsáki seeks to understand how our experiences are represented and saved as memories. New studies from his lab and others have suggested that the brain tags experiences worth remembering by repeatedly sending out sudden and powerful high-frequency brain waves. Known as “sharp wave ripples,” these waves, kicked up by the firing of many thousands of neurons within milliseconds of each other, are “like a fireworks show in the brain,” said Wannan Yang, a doctoral student in Buzsáki’s lab who led the new work, which was published in Science in March. They fire when the mammalian brain is at rest, whether during a break between tasks or during sleep. Sharp wave ripples were already known to be involved in consolidating memories or storing them. The new research shows that they’re also involved in selecting them — pointing to the importance of these waves throughout the process of long-term memory formation. It also provides neurological reasons why rest and sleep are important for retaining information. Resting and waking brains seem to run different programs: If you sleep all the time, you won’t form memories. If you’re awake all the time, you won’t form them either. “If you just run one algorithm, you will never learn anything,” Buzsáki said. “You have to have interruptions.” © 2024 the Simons Foundation.

Keyword: Learning & Memory
Link ID: 29322 - Posted: 05.23.2024

By Lee Alan Dugatkin 1 The complexity of animal social behavior is astonishing I have studied animal behavior for more than 35 years, so I’m rarely surprised at just how nuanced, subtle, and complex the social behavior of nonhuman animals can be. But, every once in a while, that “my goodness, how astonishing!” feeling—which I felt so often in graduate school—returns. That’s how I felt when I read Kevin Oh and Alexander Badyaev’s work on sexual selection and social networks in house finches (Haemorhous mexicanus). The house finches in question, I learned while researching my book, live on the campus of the University of Arizona, where, in 2003, Oh was doing his graduate work and Badyaev was a young assistant professor. Using data on thousands of finches they banded over six years, these two researchers were able to map the social network the birds relied on during breeding season. This network was composed of 25 “neighborhoods” with an average of 30 finches per group. Females rarely left their neighborhoods to interact with birds in other neighborhoods. But how much males moved around from one neighborhood to the next depended on their coloring. Those with plenty of red coloration—which females tend to prefer as mating partners—generally remained put, just like females. But drabber colored males were more likely to socialize across many neighborhoods. The question was why? The answer was what rekindled my own sense of awe in the power of natural selection to shape animal social behavior. When Oh and Bedyaev mapped reproductive success in their house finches, they found that the most colorful males did well no matter what neighborhood they were in. Drab males, however, had greater reproductive success if they tried their luck all around town—essentially, this allowed them to find just the spot where their relative coloration was greatest and therefore most likely to score them a mate. In other words, they learned to play the field, restructuring social networks in a way that served their purposes best. 2 Technology is radically changing how scientists study the behavior of animals © 2024 NautilusNext Inc.,

Keyword: Learning & Memory; Evolution
Link ID: 29305 - Posted: 05.14.2024

By Gayathri Vaidyanathan An orangutan in Sumatra surprised scientists when he was seen treating an open wound on his cheek with a poultice made from a medicinal plant. It’s the first scientific record of a wild animal healing a wound using a plant with known medicinal properties. The findings were published this week in Scientific Reports1. “It shows that orangutans and humans share knowledge. Since they live in the same habitat, I would say that’s quite obvious, but still intriguing to realize,” says Caroline Schuppli, a primatologist at the Max Planck Institute of Animal Behavior in Konstanz, Germany, and a co-author of the study. In 2009, Schuppli’s team was observing Sumatran orangutans (Pongo abelii) in the Gunung Leuser National Park in South Aceh, Indonesia, when a young male moved into the forest. He did not have a mature male’s big cheek pads, called flanges, and was probably around 20 years old, Schuppli says. He was named Rakus, or ‘greedy’ in Indonesian, after he ate all the flowers off a gardenia bush in one sitting. In 2021, Rakus underwent a growth spurt and became a mature flanged male. The researchers observed Rakus fighting with other flanged males to establish dominance and, in June 2022, a field assistant noted an open wound on his face, possibly made by the canines of another male, Schuppli says. Days later, Rakus was observed eating the stems and leaves of the creeper akar kuning (Fibraurea tinctoria), which local people use to treat diabetes, dysentery and malaria, among other conditions. Orangutans in the area rarely eat this plant. In addition to eating the leaves, Rakus chewed them without swallowing and used his fingers to smear the juice on his facial wound over seven minutes. Some flies settled on the wound, whereupon Rakus spread a poultice of leaf-mash on the wound. He ate the plant again the next day. Eight days after his injury, his wound was fully closed. © 2024 Springer Nature Limited

Keyword: Learning & Memory; Evolution
Link ID: 29290 - Posted: 05.03.2024