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Yahoo
a day ago
- Science
- Yahoo
Scientists say this trick can help bring back fading memories
When you buy through links on our articles, Future and its syndication partners may earn a commission. Half-forgotten memories can be resurrected using "mental time travel," a new study suggests. The research, published Monday (July 28) in the journal PNAS, showed that a person can rejuvenate their fading memories by recalling the emotions and thoughts they had when they first stored that memory. In fact, the researchers found that the refurbished memories were then almost as retrievable as newly formed memories. The study specifically focused on memories of learned information, as opposed to memories of events, for instance. When we learn something, that new memory teeters on a forgetting curve, like a boulder perched atop a tall mountain. As that boulder rolls downhill, we lose some details of the memory. But as it approaches the base of the memory mountain, where the incline is less steep, the rate of forgetting slows down. There are processes that "make the memories more and more stable and less sensitive to any type of forgetting processes," said study co-author Karl-Heinz Bäuml, a psychologist at the University of Regensburg in Germany. Some details remain etched into your memory, while others fade with time. But this forgetting might not be inevitable, Bäuml argued. "You can reduce this type of forgetting if you mentally travel back in time to the context of encoding," meaning when you made the memory. In the new study, Bäuml and colleagues explored how this mental time travel affected memory retrieval. The team recruited over 1,200 volunteers. Half were tasked with studying a short passage, while the other half studied lists of unrelated nouns. Each group was then split into four subgroups, which were asked to remember the material in different ways. Related: Memories aren't static in the brain — they 'drift' over time One group, which served as a point of comparison, was asked to recall the information they had just learned several times over the next hour, without performing any extra steps. The three other groups had a gap of four hours, 24 hours or seven days between learning the material and having their memories tested. Upon being tested, these three groups were asked to mentally time travel, either by recalling the thoughts and feelings they had during their first session in the lab or by looking at a subset of the information they'd learned, as a kind of primer to remember the rest. The comparison group was also retested at these later time points, and their recall, sans time travel, was used as a benchmark. Both types of mental time travel helped restore the participants' recollections, rolling their memories up the mountain to some degree. At the four-hour and 24-hour marks, these tricks improved recall by "reactivating" the memories. Remembering emotions from the earlier encoding restored about 70% of the targeted memories after four hours and 59% after 24 hours, while selective priming restored about 84% and 68% of the target memories at these time points. However, after a week, the effect of mental time travel had waned. Remembering emotions didn't restore any memories, while priming restored only 31% of the target memories. Deniz Vatansever, a cognitive neuroscientist at Fudan University in China who was not involved in the study, said the new work refines our understanding of memory. "Memory is not just linearly decaying, but actually we're able to reset it almost into its original form," he said. However, he said the real test would be to see how these findings generalize to life outside the lab. "Autobiographical memories or other experiences that we have in daily life — they're rich in emotional content; they're rich in sensory modalities," he noted. By comparison, memories of short passages and word lists lack these features. RELATED STORIES —Can your brain run out of memory? —The brain stores at least 3 copies of every memory —Sherlock Holmes' famous memory trick really works Bäuml agreed that the degree of memory rejuvenation will vary with factors not explored in the current study, such as the richness of the experiences being remembered. But for now, he said the evidence suggests that, if you're aiming to ace an exam, it might be best to schedule revision sessions with only short intervals in between. "The best way would be to distribute your mental reinstatement a little bit and do it not only after seven days, but do it after three days, six days and so forth," he said. This would "create recurring rejuvenation cycles, which keep the memories all in all at a higher level," he suggested. While this study found that single instances of mental time travel might nudge memories back up the mountain, other research has suggested that repeated practice might make it harder for the memory to roll down in the first place, said Justin Hulbert, a neuroscientist at Bates College who was not involved in the study. This might mean that memories need to be refreshed regularly at first — after an hour or two — but that later refreshes could wait longer, maybe months or years, Hulbert said. "That might mean that you have to push the boulder up the mountain fewer times to still preserve that memory over long periods," he said.
Miami Herald
5 days ago
- Health
- Miami Herald
Massive sleep study reveals surprising cost of going to bed late
As an avid Oura user, I'm no stranger to *slightly* obsessing over sleep data. I've tracked my deep sleep, REM cycles, HRV, and recovery scores like a mini scientist in a silk sleep mask. I've timed workouts based on my readiness score. When it comes to the link between sleep and performance, I'm not new here. But even with all that tracking and optimization, this new study got my attention. Researchers looked at millions of nights of sleep-over 6 million to be exact-and what they found was something most of us (myself included) tend to overlook. It's not just about how much you sleep. Related: FDA eliminates 52 food standards in sweeping deregulation move It's about when. And more specifically: what happens when you go to bed later than usual. The impact? Subtle at first. But if you're trying to be consistent with your workouts, boost your energy, or just feel better, those late nights might be holding you back. Even if you're still getting 7 to 8 hours of sleep. That's what makes this study different. Because this time, we're not just talking about sleep duration. We're talking about timing-and how it can affect your body and behavior the very next day. The study, published in PNAS, looked at over 6 million nights of sleep data from nearly 26,000 adults using wearable fitness trackers. Specifically, over 19,000 WHOOP users and nearly 6,000 Fitbit device users. Here's what they found: people who went to bed earlier were more likely to exercise the next day. And the difference? Bigger than you'd think. For example, compared to those who went to sleep around 1 a.m., people who consistently went to bed at 9 p.m. logged 28 more minutes of moderate-to-vigorous physical activity (MVPA) the next day. Even more surprising? People who slept less overall, but went to bed earlier, often exercised more than those who slept longer but went to bed later. In other words, timing beat out total sleep when it came to getting people moving. I spoke with Dr. Mark Czeisler, Resident Physician at Brigham and Women's Hospital and Clinical Fellow at Harvard Medical School, who co-authored the study led by Josh Leota, a Research Fellow at Monash University. Related: These clean food brands are rightfully challenging the FDA He explained why bedtime and not just sleep time matters: "People got the most intense exercise when they preserved their usual sleep amount, but went to bed earlier than they typically do," he said. "That suggests these health behaviors aren't competing with each other. They're best thought of as working in concert." Think about it: if you're staying up late to finish one more episode or scroll TikTok, you could be trading away the energy and motivation you'll need tomorrow. Dr. Czeisler also noted that early sleepers are more likely to get in their workouts before the day gets busy. Morning routines tend to be more reliable-and that consistency matters. While this study tracked people living their normal lives-not under lab conditions-it's truly a big moment for sleep and fitness tech. And it supports something companies like WHOOP, Fitbit, Apple Watch and Oura have been saying for years: when you sleep matters just as much as how much you sleep. The WHOOP data came from users who were already pretty active-averaging 90 minutes of MVPA daily. But the researchers confirmed the same trend in a broader group, using Fitbit data from the NIH's All of Us program. Even people who weren't exercising much still saw a difference. Earlier bedtimes meant more movement the next day. As Dr. Czeisler put it: "The way to guarantee exercise is really to protect the morning. And so going to bed earlier, you know, lends itself to doing that." So if you're trying to get consistent with your workouts, improve your energy, or just build better habits, maybe start by looking at the clock. Going to bed a little earlier might be the simplest, most powerful performance tool you're not using yet. Protect your mornings, people! I know I do... Related: Watch out Fitbit and Apple Watch, Amazon has entered the chat The Arena Media Brands, LLC THESTREET is a registered trademark of TheStreet, Inc.
The Hindu
24-07-2025
- Health
- The Hindu
Bacterial cell walls could hold clues to better human health, say CCMB scientists
Bacteria are enclosed by protective cell walls, made from a unique substance called peptidoglycan. This material is absent in other life forms, including humans, which is why many antibiotics target it. A team of scientists led by Manjula Reddy at CSIR-Centre for Cellular and Molecular Biology (CCMB), Hyderabad, has found that bacteria sometimes make mistakes while building this wall. Instead of using the correct amino acid L-alanine, they occasionally use a structurally similar one called glycine. This weakens the wall and makes bacteria more vulnerable to antibiotics. These findings have been published in the PNAS journal. Also Read | CCMB team uses E. coli to study bacterial cell wall development The bacterial cell wall is made of sugars and short chains of amino acids. Dr. Reddy's team discovered that bacteria have a special enzyme called PgeF (Peptidoglycan Editing Factor) to maintain the composition of the cell using a combination of genetics and high-resolution mass-spectrometry, according to the study's first author, Shambhavi Garde. Interestingly, a similar enzyme exists in humans. Called LACC1, it has been linked to several autoinflammatory diseases — conditions where the immune system is hyperactived, said Though LACC1's role isn't fully understood, this study suggests it might be involved in how the body responds to bacterial infections. 'By studying such vulnerabilities in cell wall synthesis, new ways of blocking bacterial growth can be designed,' the scientists said in a press release.
India Today
23-07-2025
- Science
- India Today
Not just humans, even ants follow caste. It defines their destiny
For ages, biologists have been fascinated by the world of ants, where destiny often depends on caste: queens grow large, sprout wings, and lay eggs, while their sisters remain small, wingless balance of genetics and environment in determining these roles has long been debated. Now, a study published in PNAS sheds new light on the intricate interplay between genes, body size, environment, and an ant's by Dr. Daniel Kronauer at The Rockefeller University, researchers set out to untangle whether environment or genetics is more important in shaping whether a developing ant becomes a queen or a worker. Using the clonal raider ant, Ooceraea biroi, which allows precise control of genetics and rearing conditions, the team found that size and caste are inextricably linked—but not by environment alone. The destiny is an interplay between genes, body size, environment. (Photo: Pixabay) Queens aren't just large workers; they possess wings, large ovaries, and special eyes, while workers lack these features. By manipulating food, temperature, and caregiver genotypes, the team found that these environmental factors influenced caste only by altering the ants' final body size, smaller ants remained workers, while those that grew big enough developed queen-like intriguing differences emerged when the team studied ants from different genetic lines under identical conditions. Some genetic lines produced ants that, even at small sizes, were more likely to develop queen-like traits."Genes don't just influence how big an ant grows," says Patrick Piekarski, co-author and postdoctoral researcher in Kronauer's lab, "they also set the body size threshold at which queen features appear."In other words, two ants of the same size but different genetics can have drastically different chances of becoming queens. Researchers set out to untangle whether environment or genetics is more important. (Photo: Getty) While environmental factors, like access to food, can increase or decrease overall size, only genetics determine how size translates to caste. The findings highlight that ant societies have evolved a robust, genetically controlled system for dividing roles, with genes both shaping growth and defining what that growth means to the the links between genes, size, and social roles isn't just about morphology, it's a window into the evolutionary logic behind insect societies and the roles individuals play within them.- EndsTrending Reel
Yahoo
22-07-2025
- Science
- Yahoo
Optimists Are Alike, but Pessimists Are Unique, Brain Scan Study Suggests
Optimists have similar patterns of brain activation when they think about the future—but pessimists are all different from one another, a brain scan study suggests 'All happy families are alike; each unhappy family is unhappy in its own way.' This is the first line of Leo Tolstoy's novel Anna Karenina, and it may hold a kernel of truth that goes beyond family dynamics. In a recent study of optimism, neuroscientists found an equivalent principle at play: optimists shared similar patterns of activity in a key brain region when they imagined future events, but each pessimist's brain patterns was unique. The results help neuroscientists understand what distinguishes optimism from pessimism in the brain. This is an important question because optimism is associated with better physical, mental and social health. The results were published on Monday in the Proceedings of the National Academy of Sciences USA. 'We tend to think of imagining the future as a deeply personal, subjective act,' says Kuniaki Yanagisawa, the study's lead author and a psychologist at Kobe University in Japan. 'Our study, however, shows that—especially for optimists—the way our brains do this can be similar' and suggests that such shared cognitive frameworks for imagining the future might explain why we 'click' with some people, he says. Prior studies have shown that optimists have larger social networks and higher acceptance by their peers. Yanagisawa wanted to understand 'whether this social success is just about personality,' he says, 'or if optimists might share a fundamental brain mechanism that makes it easier for them to form social connections.' [Sign up for Today in Science, a free daily newsletter] The researchers scanned participants in a functional magnetic resonance imaging (fMRI) machine while they imagined specific future events happening to either them or their spouse. Some of the events were positive; others were neutral or negative. Afterward the team had the participants take a questionnaire to determine their level of optimism or pessimism. The researchers conducted the study twice, once in a group of 37 participants and again in a group of 50. To analyze the brain scans, the researchers zoomed in on one region that's particularly active while imagining future events: the medial prefrontal cortex, located in the middle of the very front of the brain. They compared patterns of brain activation in each possible pair of participants and used statistical tests to determine how similar the activations were to each other in these pairs. The team found that only pairs consisting of two optimistic participants had similar brain activation; pairs where one or both participants were more pessimistic were dissimilar to each other. The researchers also found that optimistic people showed bigger differences between brain patterns for emotionally positive and negative events than pessimists did. A few prior studies of 'positive' social traits have shown similar results. A 2022 brain scan study showed that people who held a central position in their social network have similar activation patterns to one another—but that less central people had a lot of individual differences, or idiosyncrasies. The same pattern held true in another study of people with low versus high levels of loneliness. Elisa Baek, a social neuroscientist now at the University of Southern California and lead author of those two studies, refers to these results as examples of the 'Anna Karenina principle,' the idea that successful endeavors have similar characteristics but that unsuccessful ones are each different in their own way. 'One intriguing interpretation [of the optimism study], consistent with the Anna Karenina principle, is that there may be many different ways for a person to be pessimistic, while optimistic people tend to converge on a few shared mental models of a hopeful future,' Baek says. Together, these studies 'may point to a more general principle—that being 'on the same page' as others is a foundational mechanism that underlies the experience of social connection.' If there is an Anna Karenina principle at work for positive social traits, what would be causing it? After all, the traits we deem 'positive' vary greatly among different societies, so there's a risk of cultural bias. Yanagisawa thinks that these cultural values could actually be driving the effect—they orient people toward a specific goal that is valued in a society, such as being optimistic or having a lot of social connections, perhaps leading those individuals to behave and think similarly over time. It's also possible that optimism, as measured in this study, is picking up on related traits such as people's level of loneliness or position in a social network. 'These convergent findings raise an important question about the overlap between constructs such as optimism, loneliness and network centrality,' Baek says. 'Because the new study didn't control for loneliness or social network position, and my prior work didn't control for optimism, it is unclear how much these dimensions are overlapping or distinct.' Optimism and pessimism aren't unchanging traits; they tend to shift with age, although the trajectories vary from culture to culture. Nor is optimism an unquestioned good. 'Extreme optimism might not always be a good thing because we might not plan for the future as well as we should,' says Aleea Devitt, a psychologist at the University of Waikato in New Zealand, who studies future thinking. And 'pessimism may be a useful 'positive' trait in some situations; there's evidence that some people can be defensive pessimists, which can actually help them better prepare for the future.' Solve the daily Crossword
