Latest news with #CurrentBiology
Gizmodo
a day ago
- Health
- Gizmodo
Brain Scans Reveal Why Waking Up Is Sometimes Such a Difficult Experience
Want to wake up feeling great? The secret might not be so simple as a multi-step nighttime routine, early bedtime, or a no-device rule. A new study suggests that how we fall asleep and how we wake up the next day may not be so similar as we once thought. Neuroscientists tracked 20 people's brain activity as they woke up from sleep—sometimes naturally, sometimes by setting off an alarm—recording more than 1,000 awakenings in total. They found a pattern of neural activity signaled waking, but that the pattern was slightly different in people who were deep in dream-laden REM sleep as opposed to those in non-REM sleep. And people woken from REM sleep were more likely to say they felt tired on waking. 'The surprise is how consistent [this pattern] was across every awakening and also how it related to the subjective measures,' Francesca Siclari, the study's senior author and neuroscientist at the Netherlands Institute for Neuroscience, told Nature. The results were published this week in Current Biology. Each participant had 256 sensors attached to their scalps, which allowed the researchers to track their brain activity at a second-to-second timescale. From there, the researchers were able to reconstruct a visual map of each participant's brain activity and compared it to how sleepy each participant said they were on waking. They found that when people were roused during REM sleep, a neural 'wave of activation' moved from the front to the back of the brain: the prefrontal cortex, which manages executive function and decision-making, fired up first, followed by a slow 'wave' of alertness that ended at the region associated with vision. During non-REM sleep, the wave started in a central 'hotspot' and then progressed along the same front-to-back pattern. The findings could help researchers tease out why some people who struggle with sleep find it hard to wake up feeling refreshed, although more work is needed to understand whether other issues during sleep, like movement, may be at play. Less subjective measures of wakefulness could also help refine the results. 'Knowing exactly how brain activity is characterized during a normal awakening [means] we can better compare it to these abnormal awakenings,' Siclari told Nature.
Irish Examiner
3 days ago
- Science
- Irish Examiner
Does your cat prefer to sleep on their left side? Scientists have investigated why...
Why do I snore? What possible purpose does it serve? Our ancient hominid ancestors can't have snored; the noise would have drawn predators, such as leopards, to the sleeper. Natural selection would soon have eliminated such a tendency. Cats don't snore but they have other sleeping foibles. Alanna, our pussy, slumbers through much of the day. But she won't curl up just anywhere; she commandeers the highest available location before nodding off. That would have made good survival sense to her wild forebears. An approaching predator is easier to spot from above and is less likely to notice the sleeper. Enemies, apart from eagles, having to attack uphill from below, would be at a tactical disadvantage. But Alanna has another quirk; she always sleeps lying on her left side. I used to think that such traits were peculiar to her but, according to a paper just published in Current Biology, they aren't. Every domestic cat, it seems, has a preferred sleeping position and each one always chooses to lie on a particular side of the body. Could this 'lateral bias' be down to 'handedness'? About one in ten people is left-handed. It used be thought that ciotógs were more talented and creative than the rest of the common herd. The most famous lefties were Leonardo da Vinci and Vincent van Gogh. Barack Obama and Bill Gates both write with the left hand. However, researchers at Cornell University found no evidence that 'kicking with the left foot' meant that you were more gifted. 'Pawedness', the animal equivalent of handedness, is found in many, perhaps all, vertebrates: Parrots prefer to hold food items in one claw rather than the other. Pregnant cows sleep more often lying on their left side than on the right, whereas non-pregnant ones show no side preference. Amphibians and reptiles have similar biases. Whether fish exhibit pawedness, is uncertain. Nor is the choice of side written in stone; most dogs, for example, are right-pawed, although bitches and pups, according to one study, are more likely to be lefties. Lateral bias in sleeping positions of domestic cats: About two-thirds of cats prefer to sleep on their left side. Pictures of cats from unsplash: left cat courtesy of Noah Dustin von Weissenfluh (@noah_dustin), right cat courtesy of Gleb Kuzmenko (@badfantasy) Researchers, led by Sevim Isparta of Italy's Bari Aldo Moro University, have studied handedness in domestic cats. Examining 408 Youtube videos of sleeping pussies, they found that 65% of them sleep on their left side, while 35% chose the right. There is a division of labour between the two sides of the brain. Each side specialises in particular tasks. The right hemisphere, say the researchers, 'is dominant for threat processing and, in most species, animals react faster when a predator is approaching from the left side'. It analyses spatial information while the right amygdala responds to dangers and threats. If a cat, sleeping on its left side, is awakened by the approach of a predator, the threat would be detected in the cat's left visual field. The left side of the brain controls the right side of the body, so left visual information is processed in the right hemisphere. Sleeping on the left side, therefore, may have evolved as a 'fight or flight' mechanism to help the cat respond more quickly to danger and hunt for prey more efficiently. Left-oriented sleeper Alanna agrees! Read More Demand for ejiao has soared — which is bad news for donkeys
Gizmodo
4 days ago
- Health
- Gizmodo
Most Cats Sleep on Their Left Side, and Scientists Think They Know Why
If you're a cat owner, chances are you spend an unhealthy amount of time scrolling through your photo gallery, reviewing adorable photos of your cats for the thousandth time. While doing so, perhaps you've noticed that your cats appear to favor a certain side while sleeping. And if that happens to be the left side, new scientific research suggests you're right. This could be a survival strategy for cats, according to a recent study published in Current Biology. In the paper, the researchers explain that in mammals such as cats, the right hemisphere of the brain controls the left visual field, spatial awareness, and quick responses to threats. Sleeping on the left allows the right hemisphere of a cat's brain to be readily available to identify and coordinate a rapid escape, the scientists claim. Virtually all animals are at risk to predators while sleeping. That's a problem for cats (at least in their pre-domesticated natural state), who spend around 12 to 16 hours each day sleeping. For that reason, cats usually sleep in locations they consider safe. But the researchers were curious as to whether cats evolved other tactics to stay safe during and immediately after their frequent naps. To answer this question, the researchers analyzed 408 publicly available YouTube videos featuring cats sleeping on their sides, with the requirement that the nap had to be uninterrupted for at least ten seconds. They found that in two-thirds of the videos, the cats preferred to sleep on their left side, which the researchers then attempted to explain in terms of neuroscience. 'Since cats prefer to sleep in elevated positions, upon awakening they would immediately see predators or prey with the left side of their visual field,' the study authors explained in a statement. 'Since the right hemisphere has advanced spatial abilities and can quickly coordinate rapid escape and possibly also hunting functions, left-side sleeping would provide evolutionary benefits as a survival strategy.' Scientists Want to See Videos of Your Cat for a New Study But as the scientists themselves admit, this conclusion warrants further investigation to explore other potential factors that influence a cat's favored sleeping position. While their analysis of the videos turned up a statistically significant leftward bias at the population level, 'we obviously have no information about the sex or pregnancy status of the videotaped cats,' they wrote in the paper. Indeed, pregnancy might be another complicating variable, a trend scientists previously observed for pregnant cows. Additionally, 'pawedness'—the cat version of right- or left-handedness—should also be taken into consideration for future research, the scientists said. Overall, the authors conclude that this finding, while subject to debate, 'could provide an excellent opportunity to study the emergence of asymmetries at the population level, while also helping us to learn more about the nature of one of our favorite pets.' A quick and very unscientific population survey among Gizmodo and Kotaku's cat owners affirmed the study's findings, showing a slightly greater tendency for cats to favor their left side while sleeping. I was also able to confirm that my roommate's two cats both tend to curl up on their left side. There were, however, some outlier cases, such as Kotaku staff writer Zachary Zwiezen's feline companion, who reportedly 'just does the super tight curl and turns into a strange organic shape that, while cute, lacks any sides.' To gather more data, we'd like to invite our readers to share their cats' favored sleeping position in the comments. Photo evidence is encouraged.
New York Times
4 days ago
- Science
- New York Times
This Golden Fungus Is Spreading Wildly in North America's Forests
For a few years, foragers and fungi enthusiasts around the Midwest have been seeing something yellow. The butter-colored flushes of the golden oyster mushroom are difficult to miss. They bloom on dead or decaying trees, and they have become profuse in states around the Great Lakes. The fungi, which are native to Asia, are good to eat and easy to grow. But a new study shows that they may also be sapping the resources of native mushrooms. And their footprint is spreading fast. 'I don't think anyone would hesitate to call it invasive,' said Aishwarya Veerabahu, a mycologist and doctoral student at the University of Wisconsin-Madison and an author of the study, published Wednesday in the journal Current Biology. She and her colleagues call the golden oyster 'a literal and figurative bright yellow warning' in the study, adding that 'as of now, there are no management strategies available to control its spread.' The mushrooms were almost certainly introduced to the United States by humans, Ms. Veerabahu said. Golden oyster mushrooms and growing kits for them are sold in stores, and the fungus may have spread from backyards or compost piles. Want all of The Times? Subscribe.
Yahoo
08-07-2025
- Science
- Yahoo
Researchers unravel mystery of why cats prefer sleeping on their left
While watching hours of cat videos on social media, scientists in Germany have noticed something strange: Most cats appear to prefer sleeping on their left side. Now, a study published in the journal Current Biology has confirmed this peculiar preference and shed light on what is likely an evolutionary survival strategy. The cat nap scientists say the brain structure of cats means they may be able to react more quickly to predators or prey upon waking on their left side. Animals are of course particularly vulnerable while sleeping, and cats spend 12 to 16 hours a day doing so, often in slightly elevated positions such as on steps or sofas. A team led by Onur Güntürkün from Germany's Ruhr University Bochum analysed 408 YouTube videos of sleeping cats. Around two-thirds of the animals were said to prefer a left-sided sleeping position. The reason they believe that cats are faster to detect threats on one side is that the two hemispheres of the brain are specialized for different tasks. According to Güntürkün's team, the right hemisphere dominates spatial attention, the processing of dangers and the coordination of rapid escape movements. Cats sleeping on their left side perceive their surroundings upon waking with the left half of their visual field, which is processed in the right hemisphere. If a cat sleeps on its right side, its left visual field is restricted by its own body. "We are inclined to believe that the significant leftward bias in sleeping position in cats may have been evolutionarily driven by hemispheric asymmetries of threat processing," the researchers conclude. In fact, it's not just cats - the researchers believe that in most species, animals react more quickly when a predator approaches from the left. But there is still much mystery to the habits of a house cat, the authors admit. "Additional factors cannot be excluded," the scientists say, calling for further research into the development of such asymmetries.
