Abby Olena Leptin is a hormone released by fat cells in adult organisms, and researchers have largely focused on how it controls appetite. In a study published May 18 in Science Signaling, the authors show that leptin promotes synapse formation, or synaptogenesis, in developing rodent neurons in culture. “This paper does a really wonderful job [breaking] down the mechanisms” of leptin signaling, and the authors look at changes in synaptic function, not just at the protein level, but also on a physiological level, says Laura Cocas, a neuroscientist at Santa Clara University who was not involved in the study. “Because all of the work on the paper is done in vitro, they can do very careful analysis . . . to break down each step in the signaling pathway.” When Washington State University neuroscientist Gary Wayman and his group started working on leptin about 10 years ago, most of the research had examined the hormone’s function in regulating satiety. But “we and others knew that leptin surged during a critical period of neuronal—and in particular synaptic—development in the brain,” he says. In people, this surge happens during the third trimester of fetal development and, in rodents, over the first few weeks of life. “This surge in leptin is independent of the amount of adipose tissue that’s present. And it does not control feeding during this period because feeding circuits have not developed, so we really wanted to understand what the developmental role was.” Wayman and colleagues focused on the hippocampus because, despite being one of the best-characterized regions in the brain, there wasn’t a lot of information out there about what the leptin receptors present were doing—particularly during development. Multiple groups had also shown that leptin injected in this brain region can improve cognition and act as an antidepressant. © 1986–2021 The Scientist.

Keyword: Obesity; Learning & Memory
Link ID: 27837 - Posted: 05.29.2021

By Thomas Ling Neuroscientists are poised to gain new insights into how our minds work, thanks to a breakthrough in non-invasive 3D brain scanning. Testing the new technique – which is called diffuse optical localisation imaging (DOLI) – researchers from the University of Zurich injected a live mouse with special fluorescent microdroplets that became distributed throughout the bloodstream. Highly efficient short-wave cameras (which take advantage of a near-infrared spectral window) tracked the fluorescent to draw a map of the deep cerebral network within the mouse’s brain. Previous microscopy techniques generated unclear images due to intense light scattering. However, the DOLI technique can create a clear picture of the brain at the capillary level by using a fluorescent filled with tiny lead-sulfide-based particles called quantum dots. Additionally, unlike past procedures, DOLI does not need to break the animal’s skull and scalp to work. It is hoped the new non-invasive technique will lead to a better understanding of how brains work, including how neurological diseases first form. “Enabling high-resolution optical observations in deep living tissues represents a long-standing goal in the biomedical imaging field,” said research team leader Prof Daniel Razansky, who published the group’s findings in Optica, The Optical Society’s journal. (C) BBC

Keyword: Brain imaging
Link ID: 27836 - Posted: 05.29.2021

Amanda Heidt A damaged drainage system in the brain might be behind the spotty performance of some Alzheimer’s therapies, according to a study published April 28 in Nature. Mice modeling the neurodegenerative disorder that received plaque-busting antibodies along with a treatment to stimulate the growth of lymphatic vessels in the brain saw many of their symptoms reversed. Mice with damaged lymphatics, on the other hand, didn’t respond as well to the antibodies. This suggests that dysfunctional lymphatics might hinder the performance of antibody-based immunotherapy, an approach that has had mixed results in clinical trials among Alzheimer’s patients. “Whenever a paper provides us with a novel way to look at Alzheimer’s, such as this one does . . . it opens up a world of possibilities,” says Gabrielle Britton, a neuroscientist at the Instituto de Investigaciones Científicas y Servicios de Alta Tecnología in Panama who was not involved in the research. “The methods are sound, and [the fact] that they use several different approaches that converge on the same findings suggests a very strong paper.” The buildup of amyloid-β plaques in the brain is a hallmark of the disease, and one of the most promising immunotherapies has been a monoclonal antibody called aducanumab that breaks them up. But two clinical trials were discontinued after they yielded contradictory results, and scientists have been working ever since to figure out why as the companies continue to move forward with new trials of the therapy. The working hypothesis, Britton tells The Scientist, is that the discrepancy stems from some unexplained variation among participants. © 1986–2021 The Scientist.

Keyword: Alzheimers
Link ID: 27835 - Posted: 05.29.2021

By Mitch Leslie For the past 3 years, about 6000 middle-aged and elderly Australians have pumped iron, loaded up on greens and whole grains, strived to quell stress, and challenged their wits with computer exercises, all in an effort to preserve their cognition. They’re part of a clinical trial called Maintain Your Brain, one of about 30 current or planned studies that eschew pharmaceutical interventions and test whether altering multiple aspects of participants’ lives improves brain health. Such multidomain studies may finally reveal whether modifying diet, exercise, and other factors can slow cognitive decline as people age—or even prevent dementia. “There’s a lot of hope for multidomain trials,” says psychologist Kaarin Anstey of the University of New South Wales, Sydney, one of the principal investigators of the Maintain Your Brain trial, which will finish by the end of this year. Although people can’t escape some mental decline as they get older, lifestyle exerts a powerful influence over the risk of developing dementia—the type of severe cognitive impairment seen in conditions such as Alzheimer’s disease. Last year, an international committee of scientists and psychiatrists known as the Lancet Commission on dementia prevention, intervention, and care estimated that so-called modifiable factors account for 40% of dementia risk. Their report highlighted a dozen factors, including many familiar villains—diabetes, high blood pressure, smoking, obesity, and lack of exercise. Researchers are still probing exactly how these risk factors steal people’s faculties, but they’ve identified some likely mechanisms. Lack of physical activity may impair cognition, for instance, because exercise stimulates formation of new neurons and soothes brain inflammation. © 2021 American Association for the Advancement of Science.

Keyword: Alzheimers; Obesity
Link ID: 27834 - Posted: 05.29.2021

By Bill Hathaway A massive genome-wide association study (GWAS) of genetic and health records of 1.2 million people from four separate data banks has identified 178 gene variants linked to major depression, a disorder that will affect one of every five people during their lifetimes. The results of the study, led by the U.S. Department of Veterans Affairs (V.A.) researchers at Yale University School of Medicine and University of California-San Diego (UCSD), may one day help identify people most at risk of depression and related psychiatric disorders and help doctors prescribe drugs best suited to treat the disorder. The study was published May 27 in the journal Nature Neuroscience. For the study, the research team analyzed medical records and genomes collected from more than 300,000 participants in the V.A.’s Million Veteran Program (MVP), one of the largest and most diverse databanks of genetic and medical information in the world. These new data were combined in a meta-analysis with genetic and health records from the UK Biobank, FinnGen (a Finland-based biobank), and results from the consumer genetics company 23andMe. This part of the study included 1.2 million participants. The researchers crosschecked their findings from that analysis with an entirely separate sample of 1.3 million volunteers from 23andMe customers. When the two sets of data from the different sources were compared, genetic variants linked to depression replicated with statistical significance for most of the markers tested. Copyright © 2021 Yale University

Keyword: Depression; Genes & Behavior
Link ID: 27833 - Posted: 05.29.2021

By Virginia Hughes Late one evening last March, just before the coronavirus pandemic shut down the country, Mingzheng Wu, a graduate student at Northwestern University, plopped two male mice into a cage and watched as they explored their modest new digs: sniffing, digging, fighting a little. Sign up for Science Times: Get stories that capture the wonders of nature, the cosmos and the human body. With a few clicks on a nearby computer, Mr. Wu then switched on a blue light implanted in the front of each animal’s brain. That light activated a tiny piece of cortex, spurring neurons there to fire. Mr. Wu zapped the two mice at the same time and at the same rapid frequency — putting that portion of their brains quite literally in sync. Within a minute or two, any animus between the two creatures seemed to disappear, and they clung to each other like long-lost friends. “After a few minutes, we saw that those animals actually stayed together, and one animal was grooming the other,” said Mr. Wu, who works in the neurobiology lab of Yevgenia Kozorovitskiy. Mr. Wu and his colleagues then repeated the experiment, but zapped each animal’s cortex at frequencies different from the other’s. This time, the mice displayed far less of an urge to bond. The experiment, published this month in Nature Neuroscience, was made possible thanks to an impressive new wireless technology that allows scientists to observe — and manipulate — the brains of multiple animals as they interact with one another. “The fact that you can implant these miniaturized bits of hardware and turn neurons on and off by light, it’s just mind-blowingly cool,” said Thalia Wheatley, a social neuroscientist at Dartmouth College who was not involved in the work. © 2021 The New York Times Company

Keyword: Aggression; Sexual Behavior
Link ID: 27832 - Posted: 05.27.2021

Linda Geddes Science correspondent A blind man has had his sight partly restored after a form of gene therapy that uses pulses of light to control the activity of nerve cells – the first successful demonstration of so-called optogenetic therapy in humans. The 58-year-old man, from Brittany in northern France, was said to be “very excited” after regaining the ability to recognise, count, locate and touch different objects with the treated eye while wearing a pair of light-stimulating goggles, having lost his sight after being diagnosed with retinitis pigmentosa almost 40 years ago. The breakthrough marks an important step towards the more widespread use of optogenetics as a clinical treatment. It involves modifying nerve cells (neurons) so that they fire electrical signals when they’re exposed to certain wavelengths of light, equipping neuroscientists with the power to precisely control neuronal signalling within the brain and elsewhere. Christopher Petkov, a professor of comparative neuropsychology at Newcastle University medical school, said: “This is a tremendous development to restore vision using an innovative approach. The goal now is to see how well this might work in other patients with retinitis pigmentosa.” This group of rare, genetic disorders, which involves the loss of light-sensitive cells in the retina, affects more than 2 million people worldwide, and can lead to complete blindness. © 2021 Guardian News & Media Limited

Keyword: Vision
Link ID: 27831 - Posted: 05.27.2021

By Jackie Rocheleau It’s an attractive idea: By playing online problem-solving, matching and other games for a few minutes a day, people can improve such mental abilities as reasoning, verbal skills and memory. But whether these games deliver on those promises is up for debate. “For every study that finds some evidence, there’s an equal number of papers that find no evidence,” says Bobby Stojanoski, a cognitive neuroscientist at Western University in Ontario (SN: 3/8/17; SN: 5/9/17). Now, in perhaps the biggest real-world test of these programs, Stojanoski and colleagues pitted more than 1,000 people who regularly use brain trainers against around 7,500 people who don’t do the mini brain workouts. There was little difference between how both groups performed on a series of tests of their thinking abilities, suggesting that brain training doesn’t live up to its name, the scientists report in the April Journal of Experimental Psychology: General. “They put brain training to the test,” says Elizabeth Stine-Morrow, a cognitive aging scientist at the University of Illinois at Urbana-Champaign. While the study doesn’t show why brain trainers aren’t seeing benefits, it does show there is no link “between the amount of time spent with the brain training programs and cognition,” Stine-Morrow says. “That was pretty cool.” © Society for Science & the Public 2000–2021

Keyword: Learning & Memory
Link ID: 27830 - Posted: 05.27.2021

By Sofia Moutinho Neotropical river otters spend most of their time alone, but that doesn’t stop them from being big chatterboxes. These animals—which live in Central and South America—make a variety of squeaks and growls to convey everything from surprise to playfulness, a new study has found. The discovery could help reveal how communication evolved in all otters—and perhaps help protect these endangered animals. “The study is an in-depth and insightful investigation into the vocal repertoire of this understudied otter species,” says Alexander Saliveros, a biologist and otter expert at the University of Exeter who was not part of the research. All otters make sounds like growls and squeaks to communicate. Some social species, such as the Amazon’s giant otter (Pteronura brasiliensis), use up to 22 different call types. Others, like the lonesome North American river otter (Lontra canadensis), only have four known calls. But the neotropical river otter (L. longicaudis) has largely remained a mystery. Solitary inhabitants of rivers and lakes, they come together only once a year to mate. That makes their communication especially hard to study, says Sabrina Bettoni, a bioacoustician at the University of Vienna. So Bettoni observed three pairs of playful neotropical river otters—orphans living in a shelter on the island of Santa Catarina, off the southern coast of Brazil. The animals were kept in female-male couples year-round at the Institute Ekko Brazil, a nonprofit focused on wildlife protection. Bettoni recorded every vocalization the animals made. Then, she and colleagues analyzed the sound waves to make sure they were distinct calls with unique properties. Bettoni also spent 3 months observing the animals to understand what calls they used in which situations. © 2021 American Association for the Advancement of Science.

Keyword: Animal Communication; Language
Link ID: 27829 - Posted: 05.27.2021

By Charles Q. Choi Precise control of the tongue is often vital in life, from the way frogs capture flies to human speech (SN: 1/31/17). But much remains unknown about how the brain controls the tongue, given how its quick motions are difficult to track. Now, experiments show that the brain circuits in mice that help the tongue lick water may be the same ones that help primates reach out to grasp objects, scientists report online May 19 in Nature. Using high-speed video, neuroscientist Tejapratap Bollu and colleagues recorded the sides and bottoms of mouse tongues as the rodents drank from a waterspout. With the help of artificial intelligence to develop 3-D simulations of the appendages, the researchers discovered that successful licks required previously unknown corrective movements, too fast to be seen in standard video. These adjustments came after the tongue missed unseen or distant droplets, or when the spout was unexpectedly retracted a millimeter or more. Inhibiting a brain region that controls the body’s voluntary motions impaired these corrections, suggesting this brain area was behind these movements. These newfound corrective motions are similar to ones that primates use when reaching out with their limbs for uncertain targets, the researchers say. Those primate adjustments are also controlled by similar brain circuits as those used by the mice. “This to me shows that mammalian brains use similar principles to control the tongue and the limb,” says Bollu, now at the Salk Institute for Biological Studies in La Jolla, Calif. “Everything we know about reaching in the primates can also be used to understand how the brain controls [tongue] movements.” © Society for Science & the Public 2000–2021.

Keyword: Movement Disorders
Link ID: 27828 - Posted: 05.27.2021

R. Douglas Fields The raging bull locked its legs mid-charge. Digging its hooves into the ground, the beast came to a halt just before it would have gored the man. Not a matador, the man in the bullring standing eye-to-eye with the panting toro was the Spanish neuroscientist José Manuel Rodriguez Delgado, in a death-defying public demonstration in 1963 of how violent behavior could be squelched by a radio-controlled brain implant. Delgado had pressed a switch on a hand-held radio transmitter to energize electrodes implanted in the bull’s brain. Remote-controlled brain implants, Delgado argued, could suppress deviant behavior to achieve a “psychocivilized society.” Unsurprisingly, the prospect of manipulating the human mind with brain implants and radio beams ignited public fears that curtailed this line of research for decades. But now there is a resurgence using even more advanced technology. Laser beams, ultrasound, electromagnetic pulses, mild alternating and direct current stimulation and other methods now allow access to, and manipulation of, electrical activity in the brain with far more sophistication than the needlelike electrodes Delgado stabbed into brains. Billionaires Elon Musk of Tesla and Mark Zuckerberg of Facebook are leading the charge, pouring millions of dollars into developing brain-computer interface (BCI) technology. Musk says he wants to provide a “superintelligence layer” in the human brain to help protect us from artificial intelligence, and Zuckerberg reportedly wants users to upload their thoughts and emotions over the internet without the bother of typing. But fact and fiction are easily blurred in these deliberations. How does this technology actually work, and what is it capable of? All Rights Reserved © 2021

Keyword: Robotics; Attention
Link ID: 27827 - Posted: 05.19.2021

By Laura Sanders The key ingredient in the illicit drug known as Ecstasy or Molly may offer profound relief from post-traumatic stress disorder. When paired with intense talk therapy, MDMA drastically eased symptoms in people who had struggled with severe PTSD for years, a new study reports. “This is a big deal,” says Steven Gold, a clinical psychologist in Fort Lauderdale and professor emeritus at Nova Southeastern University in Plantation, Fla. “All other things being equal, the use of psychedelic medication can significantly improve the outcome.” The results, published May 10 in Nature Medicine, are preliminary. But the findings offer hope to the millions of people worldwide who have PTSD, for whom new treatments are desperately needed. Antidepressants such as Zoloft and Paxil are often prescribed, but the drugs don’t work for an estimated 40 to 60 percent of people with PTSD. Ninety people participated in the new study, which took place at 15 clinical sites in the United States, Canada and Israel. All the participants received 15 therapy sessions with therapists trained to guide people as they experienced the drug. Half of the participants received MDMA in three eight-hour therapy sessions; the other half received placebos during three eight-hour therapy sessions. True to its nickname Ecstasy, MDMA evokes feelings of bliss and social connectedness. The participants took the drug (or the placebo) while wearing eye covers and listening to music, and occasionally talking with their therapist about their experience. © Society for Science & the Public 2000–2021.

Keyword: Stress; Drug Abuse
Link ID: 27826 - Posted: 05.19.2021

Veronique Greenwood The hydra is a simple creature. Less than half an inch long, its tubular body has a foot at one end and a mouth at the other. The foot clings to a surface underwater — a plant or a rock, perhaps — and the mouth, ringed with tentacles, ensnares passing water fleas. It does not have a brain, or even much of a nervous system. And yet, new research shows, it sleeps. Studies by a team in South Korea and Japan showed that the hydra periodically drops into a rest state that meets the essential criteria for sleep. On the face of it, that might seem improbable. For more than a century, researchers who study sleep have looked for its purpose and structure in the brain. They have explored sleep’s connections to memory and learning. They have numbered the neural circuits that push us down into oblivious slumber and pull us back out of it. They have recorded the telltale changes in brain waves that mark our passage through different stages of sleep and tried to understand what drives them. Mountains of research and people’s daily experience attest to human sleep’s connection to the brain. But a counterpoint to this brain-centric view of sleep has emerged. Researchers have noticed that molecules produced by muscles and some other tissues outside the nervous system can regulate sleep. Sleep affects metabolism pervasively in the body, suggesting that its influence is not exclusively neurological. And a body of work that’s been growing quietly but consistently for decades has shown that simple organisms with less and less brain spend significant time doing something that looks a lot like sleep. Sometimes their behavior has been pigeonholed as only “sleeplike,” but as more details are uncovered, it has become less and less clear why that distinction is necessary. All Rights Reserved © 2021

Keyword: Sleep; Evolution
Link ID: 27825 - Posted: 05.19.2021

By Peter Mundy Since the modern era of research on autism began in the 1980s, questions about social cognition and social brain development have been of central interest to researchers. This year marks the 20th anniversary of the first annual meeting of the International Society for Autism Research (INSAR), and it is evident in this year’s meeting that the growth of social-cognitive neuroscience over the past two decades has significantly enriched autism science. For those unfamiliar with the term, social-cognitive neuroscience is the study of the brain systems that are involved in the causes and effects of social behaviors and social interaction. Some of these involve brain systems involved in thinking about other people’s thoughts or intentions, empathizing, social motivation and the impact of social attention on an individual’s thinking and emotions. At the same time, research with and for autistic people has also enriched social-cognitive neuroscience and the understanding of how our social minds develop. Autism spectrum disorder (ASD) is a complex and heterogeneous part of the human condition, or neurodiversity. It is associated with a wide range of life outcomes, from “disorder” or the profound challenges that encumber about 30 percent of affected individuals with minimal language and intellectual disability, to “differences” among people who have well-above-average abilities and accomplishments. Regardless of their outcomes, though, people on the autism spectrum travel a different path of social-cognitive neurodevelopment that appears to begin in infancy. For example, many experience some level of difficulty with social-cognitive mentalizing, also known as “theory of mind”—the mental representation of other people’s thoughts, perspectives, beliefs, intentions or emotions, which enables us to understand or predict their behaviors. © 2021 Scientific American

Keyword: Autism
Link ID: 27824 - Posted: 05.19.2021

By Nicholas Bakalar Long-term exposure to air pollution has many health consequences, including accelerating brain aging and increasing the risk for dementia. Now new research suggests that short-term exposure to polluted air, even at levels generally considered “acceptable,” may impair mental ability in the elderly. Scientists studied 954 men, average age 69, living in the greater Boston area. The men were tested at the start of the study and several times over the next 28 days using the Mini-Mental State Examination, or MMSE, a widely used test of cognitive ability. The test includes simple questions like “What year is this?” and “What season is it?,” and requires tasks like counting backward by sevens from 100. Correctly answering fewer than 25 of its 30 questions suggests mild dementia. Over the month, the researchers measured air levels of what’s known as PM 2.5, particles of soot and other fine particulate matter with a diameter of up to 2.5 microns, small enough to enter the lungs and move into bloodstream. There is no safe level of PM 2.5, but the Environmental Protection Agency considers air acceptable when it is under 12 micrograms per cubic meter. During the testing period, PM 2.5 levels in Boston averaged 10.77. Higher PM 2.5 was consistently associated with lower test scores. In weeks with the highest levels of air pollution, the men were 63 percent more likely to score below 25 on the MMSE than in weeks with the lowest levels. The study, in Nature Aging, adjusted for age, B.M.I., coronary heart disease, diabetes, alcohol consumption, smoking, high blood pressure and other factors. Dr. Andrea A. Baccarelli, the senior author and a professor of environmental science at the Columbia Mailman School of Public Health, said that these short-term effects may be reversible. “When air pollution goes down,” he said, “the brain reboots and goes back to normal. However, if repeated, these episodes produce long-term damage to the brain.” © 2021 The New York Times Company

Keyword: Learning & Memory; Neurotoxins
Link ID: 27823 - Posted: 05.19.2021

Ian Sample Science editor A man who was paralysed from the neck down in an accident more than a decade ago has written sentences using a computer system that turns imagined handwriting into words. It is the first time scientists have created sentences from brain activity linked to handwriting and paves the way for more sophisticated devices to help paralysed people communicate faster and more clearly. The man, known as T5, who is in his 60s and lost practically all movement below his neck after a spinal cord injury in 2007, was able to write 18 words a minute when connected to the system. On individual letters, his “mindwriting” was more than 94% accurate. Frank Willett, a research scientist on the project at Stanford University in California, said the approach opened the door to decoding other imagined actions, such as 10-finger touch typing and attempted speech for patients who had permanently lost their voices. “Instead of detecting letters, the algorithm would be detecting syllables, or rather phonemes, the fundamental unit of speech,” he said. Amy Orsborn, an expert in neural engineering at the University of Washington in Seattle, who was not involved in the work, called it “a remarkable advance” in the field. Scientists have developed numerous software packages and devices to help paralysed people communicate, ranging from speech recognition programs to the muscle-driven cursor system created for the late Cambridge cosmologist Stephen Hawking, who used a screen on which a cursor automatically moved over the letters of the alphabet. To select one, and to build up words, he simply tensed his cheek. © 2021 Guardian News & Media Limited

Keyword: Brain imaging; Robotics
Link ID: 27822 - Posted: 05.15.2021

By Gina Kolata Obesity has stalked Marleen Greenleaf, 58, all of her life. Like most people with obesity, she tried diet after diet. But the weight always came back. With that, she has suffered a lifetime of scorn and stigma. Jeering comments from strangers when she walked down the street. Family members who told her, when she trained for a half-marathon, “I don’t think it’s good for you.” Then, in 2018, Ms. Greenleaf, an administrator at a charter school in Washington, D.C., participated in a clinical trial for semaglutide, which is a new type of obesity drug, known as incretins. Over the course of the 68-week study, Ms. Greenleaf slowly lost 40 pounds. Until then, she had always believed that she could control her weight if she really tried. “I thought I just needed more motivation,” she said. But when she took semaglutide, she said that “immediately, the urge to eat just dissipated.” Incretins appear to elicit significant weight loss in most patients, enough to make a real medical and aesthetic difference. But experts hope that the drugs also do something else: change how society feels about people with obesity, and how people with obesity feel about themselves. If these new drugs allow obesity to be treated like a chronic disease — with medications that must be taken for a lifetime — the thought is that doctors, patients and the public might understand that obesity is truly a medical condition. © 2021 The New York Times Company

Keyword: Obesity; Hormones & Behavior
Link ID: 27821 - Posted: 05.15.2021

Rebecca Brooker & Tristin Nyman Even before the pandemic, there was plenty for expectant mothers to worry about. Pregnant women must withstand a barrage of arguably well-intentioned, but often hyperbolic, warnings about their health and what’s to come, including concerns about everything from what to eat, to what to wear, to how to feel. Health professionals know that mothers-to-be experience predictable increases in anxiety levels before infants are born. Maternal mental health has been steadily deteriorating in the U.S., particularly among poor and minority women. The calls to “be afraid, be very afraid” are, of course, countered by the equally strong cautions for pregnant women to not worry too much, lest it lead to long-term negative outcomes for them and their infants. Such warnings are not entirely off base. Maternal stress hormones cross the placenta and affect the vulnerable fetus. Fetal exposure to the stress hormone cortisol has been linked to an array of negative outcomes, including miscarriage and preterm birth, and irritable temperament for the child and increased risk of emotional problems during childhood. One thing researchers know is that anxious mothers tend to have anxious children. This common, albeit not prescriptive, phenomenon is likely due to numerous factors, both pre- and postpartum. In our laboratory, we focus on what happens when women start their pregnancies already worried or anxious and what clues we can uncover about how to help them and their children. Our research suggests that worry during pregnancy can have long-term impacts on how mothers’ brains communicate – but also that there might be some simple steps that can help rein in the effects. © 2010–2021, The Conversation US, Inc.

Keyword: Sexual Behavior; Hormones & Behavior
Link ID: 27820 - Posted: 05.15.2021

By Sofia Moutinho There’s no 9-to-5 for female northern elephant seals. After the winter breeding season, the animals spend more than 19 hours—and up to 24 hours—per day hunting in the northern Pacific Ocean, killing up to 2000 small fish daily to survive, according to a new study of these elusive animals. The work, made possible by cameras and devices attached to the seals’ heads, could also help scientists monitor other deep-ocean life. “This study is fascinating,” says Jeremy Goldbogen, a marine biologist at Stanford University who was not part of the research. “The advanced technology provides unprecedented levels of detail on where and when the elephant seals forage in a deep, dark ocean.” Northern elephant seals (Mirounga angustirostris) are mysterious animals. They appear onshore, on some Pacific Coast beaches, only twice a year: in late December or early January to mate or give birth, and about 2 months later to shed their fur. They spend the rest of their time, almost 10 months, fishing. Males, which can weigh up to 2 tons—about the weight of a small truck—hunt big fish close to the coast. Females, which are only about one-third of the size, hunt smaller fish in a deep-sea region known as the twilight zone. To get food from the zone, which reaches depths of 1500 meters, the females must hold their breath for up to 1.5 hours. “The physiological challenges that these animals face to meet their daily energetic demand is an extraordinary feat,” Goldbogen says. To find out how the females survive on the small fish—some of which are just 2 centimeters long—Japanese and U.S. researchers attached infrared video cameras with depth sensors to the heads of 48 female elephant seals. They also attached GPS trackers and a special device that could count every time a seal opened its mouth. (The researchers called their device the Kami Kami Logger, after the Japanese sound for biting, similar to the English “chomp chomp.”) © 2021 American Association for the Advancement of Science

Keyword: Sleep
Link ID: 27819 - Posted: 05.15.2021

Linda Geddes It’s a common enough scenario: you walk into your local supermarket to buy some milk, but by the time you get to the till, the milk bottle has turned into a talking fish. Then you remember you’ve got your GCSE maths exam in the morning, but you haven’t attended a maths lesson for nearly three decades. Dreams can be bafflingly bizarre, but according to a new theory of why we dream, that’s the whole point. By injecting some random weirdness into our humdrum existence, dreams leave us better equipped to cope with the unexpected. The question of why we dream has long divided scientists. Dreams’ subjective nature, and the lack of any means of recording them, makes it fiendishly difficult to prove why they occur, or even how they differ between individuals. “While various hypotheses have been put forward, many of these are contradicted by the sparse, hallucinatory, and narrative nature of dreams, a nature that seems to lack any particular function,” said Erik Hoel, a research assistant professor of neuroscience at Tufts University in Massachusetts, US. Inspired by recent insights into how machine “neural networks” learn, Hoel has proposed an alternative theory: the overfitted brain hypothesis. © 2021 Guardian News & Media Limited

Keyword: Sleep
Link ID: 27818 - Posted: 05.15.2021