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By Virginia Morell Humpback whales are known for their operatic songs that carry across the seas. Their calves, however, whisper, uttering soft squeaks and grunts to their mothers (which you can hear above). Now, a new study suggests that loud calf voices can also attract some unwanted visitors: male humpbacks, who might separate the pair by trying to mate with the mother, and killer whales, who dine on young humpbacks. To record their sounds, scientists placed temporary tagging devices on eight humpback whale mothers and calves in the Exmouth Gulf off Western Australia, where the young whales spend months suckling to gain enough weight for their annual migrations to the Antarctic or Arctic. After listening to the recordings, scientists say the calves’ careful whispers are not cries for food, as previously thought. Instead, they may help them stay in close contact with their mothers when swimming. And, say researchers, writing today in Functional Ecology, the low decibel sounds help keep would-be predators away from the “nursery.” © 2017 American Association for the Advancement of Science

Keyword: Animal Communication
Link ID: 23534 - Posted: 04.26.2017

By NICK WINGFIELD SEATTLE — Zoran Popović knows a thing or two about video games. A computer science professor at the University of Washington, Dr. Popović has worked on software algorithms that make computer-controlled characters move realistically in games like the science-fiction shooter “Destiny.” But while those games are entertainment designed to grab players by their adrenal glands, Dr. Popović’s latest creation asks players to trace lines over fuzzy images with a computer mouse. It has a slow pace with dreamy music that sounds like the ambient soundtrack inside a New Age bookstore. The point? To advance neuroscience. Since November, thousands of people have played the game, “Mozak,” which uses common tricks of the medium — points, leveling up and leader boards that publicly rank the performance of players — to crowdsource the creation of three-dimensional models of neurons. The Center for Game Science, a group at the University of Washington that Dr. Popović oversees, developed the game in collaboration with the Allen Institute for Brain Science, a nonprofit research organization founded by Paul Allen, the billionaire co-founder of Microsoft, that is seeking a better understanding of the brain. Dr. Popović had previously received wide attention in the scientific community for a puzzle game called “Foldit,” released nearly a decade ago, that harnesses the skills of players to solve riddles about the structure of proteins. The Allen Institute’s goal of cataloging the structure of neurons, the cells that transmit information throughout the nervous system, could one day help researchers understand the roots of neurodegenerative diseases like Alzheimer’s and Parkinson’s and their treatment. Neurons come in devilishly complex shapes and staggering quantities — about 100 million and 87 billion in mouse and human brains, both of which players can work on in Mozak. © 2017 The New York Times Company

Keyword: Brain imaging
Link ID: 23533 - Posted: 04.25.2017

Doing moderate exercise several times a week is the best way to keep the mind sharp if you're over 50, research suggests. Thinking and memory skills were most improved when people exercised the heart and muscles on a regular basis, a review of 39 studies found. This remained true in those who already showed signs of cognitive decline. Taking up exercise at any age was worthwhile for the mind and body, the Australian researchers said. Exercises such as T'ai Chi were recommended for people over the age of 50 who couldn't manage other more challenging forms of exercise, the study in the British Journal of Sports Medicine said. Physical activity has long been known to reduce the risk of a number of diseases, including type-2 diabetes and some cancers, and it is thought to play a role in warding off the brain's natural decline as we enter middle age. The theory is that through exercise the brain receives a greater supply of blood, oxygen and nutrients that boost its health as well as a growth hormone that helps the formation of new neurons and connections. In this analysis of previous studies, researchers from the University of Canberra looked at the effects of at least four weeks of structured physical exercise on the brain function of adults. In a variety of brain tests, they found evidence of aerobic exercise improving cognitive abilities, such as thinking, reading, learning and reasoning, while muscle training - for example, using weights - had a significant effect on memory and the brain's ability to plan and organise, the so-called executive functions. Joe Northey, study author and researcher from the Research Institute for Sport and Exercise at Canberra, said the findings were convincing enough to enable both types of exercise to be prescribed to improve brain health in the over-50s. © 2017 BBC.

Keyword: Alzheimers
Link ID: 23532 - Posted: 04.25.2017

By Lauren Gravitz, Connor was diagnosed with autism early — when he was just 18 months old. His condition was already obvious by then. “He was lining things up, switching lights on and off, on and off,” says his mother, Melissa. He was bright, but he didn’t speak much until age 3, and he was easily frustrated. Once he started school, he couldn’t sit still in class, called out answers without raising his hand and got visibly upset when he couldn’t master a math concept or a handwriting task quickly enough. “One time, he rolled himself up into the carpet like a burrito and wouldn’t come out until I got there,” Melissa recalls. (All families in this story are identified by first name only, to protect their privacy.) Connor was prescribed his first psychiatric drug, methylphenidate (Ritalin), at age 6. That didn’t last long, but when he was 7, his parents tried again. A psychiatrist suggested a low dose of amphetamine and dextroamphetamine (Adderall), a stimulant commonly used to treat attention deficit hyperactivity disorder (ADHD). The drug seemed to improve his time at school: He was able to sit still for longer periods of time and focus on what his teachers were saying. His chicken-scratch handwriting became legible. Then, it became neat. Then perfect. And then it became something Connor began to obsess over. “We were told that these are the gives and takes; if it’s helping him enough to get through school, you have to decide if it’s worth it,” Melissa says. It was worth it — for a while. © 2017 Scientific American

Keyword: Autism
Link ID: 23531 - Posted: 04.25.2017

By Clare Wilson Could fasting boost your brainpower? A stomach hormone that stimulates appetite seems to promote the growth of new brain cells and protect them from the effects of ageing – and may explain why some people say that fasting makes them feel mentally sharper. When ghrelin was first discovered, it became known as the hunger hormone. It is made by the stomach when it gets empty, and whenever we go a few hours without food its levels rise in our blood. But there is also evidence that ghrelin can enhance cognition. Animals that have reduced-calorie diets have better mental abilities, and ghrelin might be part of the reason why. Injecting the hormone into mice improves their performance in learning and memory tests, and seems to boost the number of neuron connections in their brains. Now Jeffrey Davies at Swansea University, UK, and his team have found further evidence that ghrelin can stimulate brain cells to divide and multiply, a process called neurogenesis. When they added the hormone to mouse brain cells grown in a dish, it switched on a gene known to trigger neurogenesis, called fibroblast growth factor. If the same effect happens in animals, this could be how ghrelin exerts its effects on memory, says Davies, whose work was presented at the British Neuroscience Association conference this month. © Copyright Reed Business Information Ltd.

Keyword: Obesity; Neurogenesis
Link ID: 23530 - Posted: 04.25.2017

Beau Lotto When you open your eyes, do you see the world as it really is? Do we see reality? Humans have been asking themselves this question for thousands of years. From the shadows on the wall of Plato’s cave in “The Republic” to Morpheus offering Neo the red pill or the blue bill in “The Matrix,” the notion that what we see might not be what is truly there has troubled and tantalized us. In the eighteenth century, the philosopher Immanuel Kant argued that we can never have access to the Ding an sich, the unfiltered “thing-in-itself ” of objective reality. Great minds of history have taken up this perplexing question again and again. They all had theories, but now neuroscience has an answer. The answer is that we don’t see reality. The world exists. It’s just that we don’t see it. We do not experience the world as it is because our brain didn’t evolve to do so. It’s a paradox of sorts: Your brain gives you the impression that your perceptions are objectively real, yet the sensory processes that make perception possible actually separate you from ever accessing that reality directly. Our five senses are like a keyboard to a computer — they provide the means for information from the world to get in, but they have very little to do with what is then experienced in perception. They are in essence just mechanical media, and so play only a limited role in what we perceive. In fact, in terms of the sheer number of neural connections, just 10 percent of the information our brains use to see comes from our eyes. The rest comes from other parts of our brains, and this other 90 percent is in large part what this book is about. Perception derives not just from our five senses but from our brain’s seemingly infinitely sophisticated network that makes sense of all the incoming information. © 2017 The Associated Press.

Keyword: Vision
Link ID: 23529 - Posted: 04.25.2017

By Diana Kwon Most of us will laugh at a good joke, but we also laugh when we are not actually amused. Fake chuckles are common in social situations—such as during an important interview or a promising first date. “Laughter is really interesting because we observe it across all human cultures and in other species,” says Carolyn McGettigan, a cognitive neuroscientist at Royal Holloway, University of London. “It's an incredibly important social signal.” In a 2013 study, McGettigan, then a postdoctoral researcher at University College London, and her colleagues scanned the brains of 21 participants while they passively listened to clips of laughter elicited by funny YouTube videos or produced on command (with instructions to sound as natural as possible). Subjects whose medial prefrontal cortex “lit up” more when hearing the posed laughter were better at detecting whether laughs were genuine or not in a subsequent test. (This brain region is involved in understanding the viewpoint of others.) “If you hear a laugh that seems ambiguous in terms of what the person means,” McGettigan explains, “it makes sense that you're going to try to work out why this person sounds like this.” In a follow-up study in 2016, McGettigan and her colleagues recruited a fresh set of participants to rate the laugh tracks on various qualities, such as authenticity and positivity. They compared these findings with the original brain data and found that the activity in the medial prefrontal cortex was negatively correlated with the genuineness of the laughs. Their analyses also revealed that both types of laughter engaged the auditory cortices, although activity in these brain regions increased as the laughs became happier, more energetic and more authentic. © 2017 Scientific American,

Keyword: Emotions
Link ID: 23528 - Posted: 04.24.2017

Austin Frakt The burden of substance abuse disorders can fall heavily on the families and friends of those who battle addictions. But society also pays a great deal through increased crime. Treatment programs can reduce those costs. For at least two decades, we’ve known substance use and crime go hand in hand. More than half of violent offenders and one-third of property offenders say they committed crimes while under the influence of alcohol or drugs. Researchers with the Centers for Disease Control and Prevention recently estimated that prescription opioid abuse, dependence and overdoses cost the public sector $23 billion a year, with a third of that attributable to crime. An additional $55 billion per year reflects private-sector costs attributable to productivity losses and health care expenses. About 80,000 Americans are incarcerated for opioid-related crimes alone. The total annual economic burden of all substance use disorders — not just those involving opioids — is in the hundreds of billions of dollars. In an editorial accompanying the C.D.C. researchers’ study, Harold Pollack, co-director of the University of Chicago Crime Lab, wrote that opioid-associated crime, like all crime, extracts an even larger toll when you consider its impact on families and communities. “The most important reason to support treatment is to improve the well-being and social function of people with addiction disorders,” Mr. Pollack said. But there are other social benefits. When the criminally active get help for this, “the economic value of crime reduction largely or totally offsets the costs of treatment,” he added. Relative to the costs of crime alone, treatment for substance use disorders is a good deal. Even though a typical burglary may result in a few thousand dollars of tangible losses, researchers have estimated that people are willing to pay 10 times that amount to avoid that loss and 100 times more to avoid armed robbery. This reflects the fact that crime exacts a large psychological toll — the threat or climate of it is far more costly than the crimes themselves. © 2017 The New York Times Company

Keyword: Drug Abuse
Link ID: 23527 - Posted: 04.24.2017

Jonathan Rée Beau Lotto is a gung-ho neuroscientist. “[The] great minds of history,” he says, “had theories, but now neuroscience has an answer.” The latest research has, it seems, established that everything you experience “takes place in the brain” and that “you never, ever see reality!” (Lotto loves his italics and exclamation marks.) Your brain may be beautiful, but “what makes it beautiful is that it is delusional” and you should therefore get shot of your inhibitions and summon the courage to “deviate!” Perhaps we should back up a little. Early in the book, Lotto mentions a French scientist called Michel Chevreul who started working at the Gobelins textile factory in Paris in the 1820s. Chevreul had to deal with complaints about coloured yarns that seemed to fade after being woven into tapestries, and his patient chemical analyses did not get him anywhere. But then he shifted his attention from the science of dyestuffs to the psychology of perception, and he was on the way to a solution: colours, he discovered, change their appearance when looked at side by side. I needed respite from Lotto’s exclamation marks so I spent an afternoon in the British Library looking through a gorgeous old volume in which Chevreul expounded his “law of the simultaneous contrast of colours”. Chevreul began by showing how a black line has drastic effects on the appearance of adjacent colours, and how a red patch makes its surroundings look green. He then discussed the difference between colours in an object and colours in a painting, and offered suggestions about the design of picture frames and the use of colour in theatre; and he finished with wonderful planting plans for beds of multicoloured crocuses and dahlias. The book is itself an exuberant work of art, with tinted pages and fold-out arrays of coloured dots looking like prototypes of the spot paintings of Damien Hirst.

Keyword: Vision
Link ID: 23526 - Posted: 04.24.2017

By Cormac McCarthy I call it the Kekulé Problem because among the myriad instances of scientific problems solved in the sleep of the inquirer Kekulé’s is probably the best known. He was trying to arrive at the configuration of the benzene molecule and not making much progress when he fell asleep in front of the fire and had his famous dream of a snake coiled in a hoop with its tail in its mouth—the ouroboros of mythology—and woke exclaiming to himself: “It’s a ring. The molecule is in the form of a ring.” Well. The problem of course—not Kekulé’s but ours—is that since the unconscious understands language perfectly well or it would not understand the problem in the first place, why doesnt it simply answer Kekulé’s question with something like: “Kekulé, it’s a bloody ring.” To which our scientist might respond: “Okay. Got it. Thanks.” Why the snake? That is, why is the unconscious so loathe to speak to us? Why the images, metaphors, pictures? Why the dreams, for that matter. A logical place to begin would be to define what the unconscious is in the first place. To do this we have to set aside the jargon of modern psychology and get back to biology. The unconscious is a biological system before it is anything else. To put it as pithily as possibly—and as accurately—the unconscious is a machine for operating an animal. All animals have an unconscious. If they didnt they would be plants. We may sometimes credit ours with duties it doesnt actually perform. Systems at a certain level of necessity may require their own mechanics of governance. Breathing, for instance, is not controlled by the unconscious but by the pons and the medulla oblongata, two systems located in the brainstem. Except of course in the case of cetaceans, who have to breathe when they come up for air. An autonomous system wouldnt work here. The first dolphin anesthetized on an operating table simply died. (How do they sleep? With half of their brain alternately.) But the duties of the unconscious are beyond counting. Everything from scratching an itch to solving math problems. © 2017 NautilusThink Inc,

Keyword: Language; Consciousness
Link ID: 23525 - Posted: 04.22.2017

By Chris Baraniuk Bat-detecting drones could help us find out what the animals get up to when flying. Ultrasonic detectors on drones in the air and on the water are listening in on bat calls, in the hope of discovering more about the mammals’ lives beyond the reach of ground-based monitoring devices. Drone-builder Tom Moore and bat enthusiast Tom August have developed three different drones to listen for bat calls while patrolling a pre-planned route. Since launching the scheme, known as Project Erebus, in 2014, they have experimented with two flying drones and one motorised boat, all equipped with ultrasonic detectors. The pair’s latest tests have demonstrated the detection capabilities of the two airborne drone models: a quadcopter and a fixed-wing drone. Last month, the quadcopter successfully followed a predetermined course and picked up simulated bat calls produced by an ultrasonic transmitter. The bat signal Moore says one of the major hurdles is detecting the call of bats over the noise of the drones’ propellers, which emit loud ultrasonic frequencies. They overcame this with the quadcopter by dangling the detector underneath the body and rotors of the drone. This is not such a problem for the water-based drone. Last year, Moore and August tested a remote-controlled boat in Oxfordshire, UK, and picked up bat calls thought to belong to common pipistrelle and Daubenton’s bats. The different species often emit different ultrasonic frequencies. © Copyright Reed Business Information Ltd.

Keyword: Hearing; Animal Migration
Link ID: 23524 - Posted: 04.22.2017

By Meredith Knight A complex cascade of biochemical signals determines what we eat, when we eat and how much we eat. Our digestive tracts and fat cells are known to secrete hormones that drive our hunger levels and our sense of satisfaction after eating. Now a new player has come to the table, our bones. A paper published this March in Nature shows bone cells secrete a hormone called lipocalin 2—and it has a surprising effect in mouse experiments of reducing appetite and stabilizing blood sugar independently of other hormones Stavroula Kousteni, a physiologist at Columbia University College of Physicians and Surgeons, and her colleagues showed 90 percent of the hormone lipocalin 2 was produced by osteoblasts, bone cells that create the chemicals necessary to build new bone. Because of its chemical structure scientists previously thought fat cells made the hormone. Lipocalin 2 is released after eating and reaches peak levels about an hour after a meal. When researchers genetically designed mice with defective lipocalin 2 genes in bone, the mice had 20 percent more body fat than mice that had the defective gene inserted into fatty tissue. The animals also ate 16 percent more chow. When mice with the broken gene were injected with lipocalin 2, their feeding behavior returned to normal. Injections of the hormone even reduced eating and improved blood sugar and insulin regulation in healthy mice. “In general, we found we could improve their metabolic phenotype,” Kousteni says. © 2017 Scientific American

Keyword: Obesity
Link ID: 23523 - Posted: 04.22.2017

Paula Span “During the past four weeks, have you been tired? Been exhausted? Had difficulty getting motivated to do anything at all?” These questions — which a substantial chunk of the population probably could answer in the affirmative — appeared on a questionnaire used in a major European study published recently in The New England Journal of Medicine. The authors were researching the effectiveness of a drug that is widely, if controversially, used to treat older adults with subclinical hypothyroidism, better known as a slightly underactive thyroid. So many Americans take that medication — levothyroxine (brand name Synthroid) — that it topped the list of prescription drugs dispensed in the United States in 2015, according to the research firm QuintilesIMS Institute. With 121 million prescriptions annually, levothyroxine outpaced statins, blood pressure meds — and everything else. A Johns Hopkins survey published last year found that more than 15 percent of older Americans were taking it. So you’d think these study results would come as shocking news: The European team reported that in older people with mild hypothyroidism, the drug had no significant effect on symptoms. At all. Instead, the results bolstered what a number of geriatricians and endocrinologists have suspected for years. “It’s a strong signal that this is an overused medication,” said Dr. Juan Brito, an endocrinologist at the Mayo Clinic. “Some people really need this medicine, but not the vast majority of people who are taking it.” © 2017 The New York Times Company

Keyword: Hormones & Behavior
Link ID: 23522 - Posted: 04.22.2017

By Emily Langer Jaak Panksepp, a neuroscientist who helped reveal the emotional lives of animals by tickling rats and listening to their ultrasonic laughter in experiments that upended his field and opened new possibilities for the treatment of depression and other forms of mental illness, died April 18 at his home in Bowling Green, Ohio. He was 73. The cause was cancer, said his wife, Anesa Miller. For much of his career, Dr. Panksepp was brushed aside by colleagues who accepted the prevailing notion that emotions were uniquely human experiences. Dr. Panksepp — along with many pet owners — suspected otherwise, and he sought to prove his intuition through the rigors of science. “People don’t have a monopoly on emotion,” he once said. “Rather, despair, joy and love are ancient, elemental responses that have helped all sorts of creatures survive and thrive in the natural world.” He was long associated with Bowling Green State University where, in the late 1990s, he conducted the experiments with lab rats that would vault him to national renown. He recalled walking into the laboratory one day and remarking to an assistant, “Let’s go tickle some rats.” He credited a graduate student with repurposing a bat detector — a tool capable of recording high-pitched sounds — as the instrument they would use to listen into the rats’ laughterlike chirps. “Lo and behold,” he told the Toledo Blade in 1998, “it sounded like a playground!” © 1996-2017 The Washington Post

Keyword: Emotions
Link ID: 23521 - Posted: 04.22.2017

By BENEDICT CAREY Well-timed pulses from electrodes implanted in the brain can enhance memory in some people, scientists reported on Thursday, in the most rigorous demonstration to date of how a pacemaker-like approach might help reduce symptoms of dementia, head injuries and other conditions. The report is the result of decades of work decoding brain signals, helped along in recent years by large Department of Defense grants intended to develop novel treatments for people with traumatic brain injuries, a signature wound of the Iraq and Afghanistan wars. The research, led by a team at the University of Pennsylvania, is published in the journal Current Biology. Previous attempts to stimulate human memory with implanted electrodes had produced mixed results: Some experiments seemed to sharpen memory, but others muddled it. The new paper resolves this confusion by demonstrating that the timing of the stimulation is crucial. Zapping memory areas when they are functioning poorly improves the brain’s encoding of new information. But doing so when those areas are operating well — as they do for stretches of the day in most everyone, including those with deficits — impairs the process. “We all have good days and bad days, times when we’re foggy, or when we’re sharp,” said Michael Kahana, who with Youssef Ezzyat led the research team. “We found that jostling the system when it’s in a low-functioning state can jump it to a high-functioning one.” Researchers cautioned that implantation is a delicate procedure and that the reported improvements may not apply broadly. The study was of epilepsy patients; scientists still have much work to do to determine whether this approach has the same potential in people with other conditions, and if so how best to apply it. But in establishing the importance of timing, the field seems to have turned a corner, experts said. © 2017 The New York Times Company

Keyword: Learning & Memory; Epilepsy
Link ID: 23520 - Posted: 04.21.2017

Hannah Devlin Science correspondent They feel no pain, don’t get cancer and look like baggy-skinned sausages with teeth: the naked mole rat is already famously weird. Now scientists have discovered what could be the subterranean rodents’ strangest trait yet: they can survive without oxygen by switching to a metabolic strategy normally used by plants. By switching from a glucose-based metabolic system, which depends on oxygen, to one that uses fructose instead, mole rats can cope with nearly twenty minutes in air with 0% oxygen. Under the same conditions, a human would die within minutes. “The naked mole rat has simply rearranged some basic building-blocks of metabolism to make it super-tolerant to low oxygen conditions,” said Thomas Park, professor of biological sciences at the University of Illinois at Chicago, who made the discovery after studying the species for 18 years. The apparently unique metabolic strategy probably evolved along with the mole rats’ niche life-style, he said. The animals live in stuffy, hyper-crowded burrows, with chambers in which a hundred-odd colony mates sleep together in a heap of hairless bodies. Scientists were aware that oxygen supplies in the mole rats’ tunnels drop to levels that would be unsurvivable for other land mammals, but until now had not tested the limits of their ability to cope with oxygen deprivation, or how this works biologically. In the latest study, published in the journal Science, the team found that mole rats showed no ill effects after five hours breathing air with 5% oxygen – slightly lower that oxygen levels at the summit of Everest. Laboratory mice, by contrast, died within ten minutes. © 2017 Guardian News and Media Limited

Keyword: Obesity
Link ID: 23519 - Posted: 04.21.2017

By TANYA FRANK It begins in the laundry room in the early hours of the morning. I find him alone, tracing the wires of the telephone circuit board. “This is how they are monitoring us,” my son whispers. “We have to cut some stuff out, change the receiver, I can do it.” “Who?” I ask. “Who is monitoring us? And why?” He puts a finger to his lips to quiet me, and begins rifling through the tool kit. He doesn’t seem quite sure what he is looking for. He has never rerouted wires in his life, and besides, it is 2009 and we have suspended our landline. These wires that my 19-year-old is obsessing over are part of a defunct apparatus from a bygone age. I shiver in this damp afterthought of a room, but not from the concrete floor under my bare feet. I’m a Londoner with a tolerance for winter. It’s nerves that have me shaking. I am scared of my own child. My partner is in San Francisco, and we are in Los Angeles. There is no national health system here. We are unmoored, just my boy and me above a twinkling metropolis of strangers. “We can’t trust anybody,” he writes. “Our computers and phones are bugged. Listen, hear that?” I shake my head, unable to detect anything. “It’s a helicopter spying on us.” When it sinks in that this is not a delirium that can be eased with Advil and a good night’s sleep, and when I stop denying that my son is armed, I take him to the closest psychiatric hospital, where he is involuntarily held for 72 hours, considered a danger to himself or others. His symptomology is examined and classified as if he is some rare and delicate butterfly, and he emerges with a label: schizoaffective disorder. It is a complex condition with traits of both schizophrenia (a thought disorder) and bipolar (a mood disorder). Basically, my son had a psychotic break. That’s what they call it when someone disintegrates from his psyche. © 2017 The New York Times Company

Keyword: Schizophrenia
Link ID: 23518 - Posted: 04.21.2017

Laura Sanders Plasma taken from human umbilical cords can rejuvenate old mice’s brains and improve their memories, a new study suggests. The results, published online April 19 in Nature, may ultimately help scientists develop ways to stave off aging. Earlier studies have turned up youthful effects of young mice’s blood on old mice (SN: 12/27/14, p. 21). Human plasma, the new results suggest, confers similar benefits, says study coauthor Joseph Castellano, a neuroscientist at Stanford University. The study also identifies a protein that’s particularly important for the youthful effects, a detail that “adds a nice piece to the puzzle,” Castellano says. Identifying the exact components responsible for rejuvenating effects is important, says geroscientist Matt Kaeberlein of the University of Washington in Seattle. That knowledge will bring scientists closer to understanding how old tissues can be rejuvenated. And having the precise compounds in hand means that scientists might have an easier time translating therapies to people. Kaeberlein cautions that the benefits were in mice, not people. Still, he says, “there is good reason to be optimistic that some of these approaches will have similar effects on health span in people.” Like people, as mice age, brain performance begins to slip. Compared with younger generations, elderly mice perform worse on some tests of learning and memory, taking longer to remember the location of an escape route out of a maze, for instance. Researchers suspect that these deficits come from age-related trouble in the hippocampus, a brain structure important for learning and memory. |© Society for Science & the Public 2000 - 2017

Keyword: Development of the Brain
Link ID: 23517 - Posted: 04.20.2017

Carl Zimmer The oldfield mouse doesn’t seem extraordinary. With soulful black eyes and tiny teacup ears, the rodent lives a humdrum life scurrying about meadows and beaches in the Southeast. But field biologists have long known that when it comes to sex and family life, this mouse is remarkable: Peromyscus polionotus is monogamous — an exception among mammals — and a solicitous parent. Fathers and mothers will dig burrows together and build elaborate nests when pups are on the way; after they’re born, the father will help tend to the pups, retrieving them when they fall out of the nest, licking them, and huddling to keep them warm. In a pioneering study published on Wednesday in the journal Nature, researchers at Harvard University identified a genetic basis for this distinctive behavior. It is the first time that scientists have linked DNA to variations in parenting habits among mammals. Dieter Lukas, an evolutionary biologist at the University of Cambridge who was not involved in the research, hailed the study as a sophisticated tour de force, saying that uncovering these links “is like designing a tool to follow individual threads through a large colorful tapestry.” The findings may one day help scientists make sense of how human couples bond and care for their children. Mammals share many of the genes governing the production of hormones and neurotransmitters in the brain. Variations in how they function may explain why most species are promiscuous, why a few are monogamous — and why some, like humans, are somewhere in between. “We can go from the bottom up and build our knowledge base, and then ask questions about human biology,” said Gene E. Robinson, a biologist at the University of Illinois who was not involved in the new work. © 2017 The New York Times Company

Keyword: Sexual Behavior; Genes & Behavior
Link ID: 23516 - Posted: 04.20.2017

Amber Dance Biologist Leo Smith held an unusual job while an undergraduate student in San Diego. Twice a year, he tagged along on a chartered boat with elderly passengers. The group needed him to identify two particular species of rockfish, the chilipepper rockfish and the California shortspine thornyhead. Once he’d found the red-orange creatures, the passengers would stab themselves in the arms with the fishes’ spines. Doing so, the seniors believed, would relieve their aching arthritic joints. Smith, now at the University of Kansas in Lawrence, didn’t think much of the practice at the time, but now he wonders if those passengers were on to something. Though there’s no evidence that anything in rockfish venom can alleviate pain — most fish stings are, in fact, quite painful themselves — some scientists suspect fish venom is worth a look. Studying the way venom molecules from diverse fishes inflict pain might help researchers understand how nerve cells sense pain and lead to novel ways to dull the sensation. Smith is one of a handful of scientists who are studying fish venoms, and there’s plenty to investigate. An estimated 7 to 9 percent of fishes, close to 3,000 species, are venomous, Smith’s work suggests. Venomous fishes are found in freshwater and saltwater, including some stingrays, catfishes and stonefishes. Some, such as certain fang blennies, are favorites in home aquariums. Yet stinging fishes haven’t gotten the same attention from scientists as snakes and other venomous creatures. |© Society for Science & the Public 2000 - 2017

Keyword: Pain & Touch; Neurotoxins
Link ID: 23515 - Posted: 04.20.2017