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By Kelly Servick The dark, thumping cavern of an MRI scanner can be a lonely place. How can scientists interested in the neural activity underlying social interactions capture an engaged, conversing brain while its owner is so isolated? Two research teams are advancing a curious solution: squeezing two people into one scanner. One such MRI setup is under development with new funding from the U.S. National Science Foundation (NSF), and another has undergone initial testing described in a preprint last month. These designs have yet to prove that their scientific payoff justifies their cost and complexity, plus the requirement that two people endure a constricted almost-hug, in some cases for 1 hour or more. But the two groups hope to open up new ways to study how brains exchange subtle social and emotional cues bound up in facial expressions, eye contact, and physical touch. The tool could “greatly expand the range of investigations possible,” says Winrich Freiwald, a neuroscientist at Rockefeller University. “This is really exciting.” Functional magnetic resonance imaging (fMRI), which measures blood oxygenation to estimate neural activity, is already a common tool for studying social processes. But compared with real social interaction, these experiments are “reduced and artificial,” says Lauri Nummenmaa, a neuroscientist at the University of Turku in Finland. Participants often look at static photos of faces or listen to recordings of speech while lying in a scanner. But photos can’t show the subtle flow of emotions across people’s faces, and recordings don’t allow the give and take of real conversation. © 2019 American Association for the Advancement of Science

Keyword: Brain imaging
Link ID: 26949 - Posted: 01.10.2020

Nell Greenfieldboyce Parrots can perform impressive feats of intelligence, and a new study suggests that some of these "feathered apes" may also practice acts of kindness. African grey parrots voluntarily helped a partner get a food reward by giving the other bird a valuable metal token that could be exchanged for a walnut, according to a newly published report in the journal Current Biology. "This was really surprising that they did this so spontaneously and so readily," says Désirée Brucks, a biologist at ETH Zürich in Switzerland who is interested in the evolution of altruism. Children as young as 1 seem highly motivated to help others, and scientists used to think this kind of prosocial behavior was uniquely human. More recent research has explored "helping" behavior in other species, everything from nonhuman primates to rats and bats. To see whether intelligent birds might help out a feathered pal, Brucks and Auguste von Bayern of the Max Planck Institute for Ornithology in Germany tested African grey parrots. They used parrots that had previously been trained to understand that specific tokens, in the form of small metal rings, could be traded for a food treat through an exchange window. In their experiment, this exchange window was covered up and closed on one bird's cage, making it impossible for that bird to trade. The bird had a pile of tokens in its cage but no way to use them. Meanwhile, its neighbor in an adjacent cage had an open exchange window — but no tokens for food. © 2020 npr

Keyword: Emotions; Evolution
Link ID: 26948 - Posted: 01.10.2020

Kristen S. Morrow Human beings used to be defined as “the tool-maker” species. But the uniqueness of this description was challenged in the 1960s when Dr. Jane Goodall discovered that chimpanzees will pick and modify grass stems to use to collect termites. Her observations called into question homo sapiens‘ very place in the world. Since then scientists’ knowledge of animal tool use has expanded exponentially. We now know that monkeys, crows, parrots, pigs and many other animals can use tools, and research on animal tool use changed our understanding of how animals think and learn. Studying animal tooling – defined as the process of using an object to achieve a mechanical outcome on a target – can also provide clues to the mysteries of human evolution. Our human ancestors’ shift to making and using tools is linked to evolutionary changes in hand anatomy, a transition to walking on two rather than four feet and increased brain size. But using found stones as pounding tools doesn’t require any of these advanced evolutionary traits; it likely came about before humans began to manufacture tools. By studying this percussive tool use in monkeys, researchers like my colleagues and I can infer how early human ancestors practiced the same skills before modern hands, posture and brains evolved. Understanding wild animals’ memory, thinking and problem-solving abilities is no easy task. In experimental research where animals are asked to perform a behavior or solve a problem, there should be no distractions – like a predator popping up. But wild animals come and go as they please, over large spaces, and researchers cannot control what is happening around them. © 2010–2020, The Conversation US, Inc.

Keyword: Evolution
Link ID: 26947 - Posted: 01.10.2020

By Philippa Roxby Health reporter A sleep disorder that can leave people gasping for breath at night could be linked to the amount of fat on their tongues, a study suggests. When sleep apnoea patients lost weight, it was the reduction in tongue fat that lay behind the resulting improvements, researchers said. Larger and fattier tongues are more common among obese patients. But the Pennsylvania team said other people with fatty tongues may also be at risk of the sleep disorder. The researchers now plan to work out which low-fat diets are particularly good at slimming down the tongue. Tongue tied "You talk, eat and breathe with your tongue - so why is fat deposited there?" said study author Dr Richard Schwab, of Perelman School of Medicine, Philadelphia. "It's not clear why - it could be genetic or environmental - but the less fat there is, the less likely the tongue is to collapse during sleep." Sleep apnoea is a common disorder that can cause loud snoring, noisy breathing and jerky movements when asleep. It can also cause sleepiness during the day, which can affect quality of life. The most common type is obstructive sleep apnoea, in which the upper airway gets partly or completely blocked during sleep. Those who are overweight or who have a large neck or tonsils are more likely to have the condition. Researchers at the Perelman School of Medicine, University of Pennsylvania, scanned 67 people with obstructive sleep apnoea who were obese and had lost 10% of their body weight, improving their symptoms improved by 30%. © 2020 BBC.

Keyword: Sleep; Obesity
Link ID: 26946 - Posted: 01.10.2020

By Veronique Greenwood The cuttlefish hovers in the aquarium, its fins rippling and large, limpid eyes glistening. When a scientist drops a shrimp in, this cousin of the squid and octopus pauses, aims and shoots its tentacles around the prize. There’s just one unusual detail: The diminutive cephalopod is wearing snazzy 3-D glasses. Putting 3-D glasses on a cuttlefish is not the simplest task ever performed in the service of science. “Some individuals will not wear them no matter how much I try,” said Trevor Wardill, a sensory neuroscientist at the University of Minnesota, who with other colleagues managed to gently lift the cephalopods from an aquarium, dab them between the eyes with a bit of glue and some Velcro and fit the creatures with blue-and-red specs. The whimsical eyewear was part of an attempt to tell whether cuttlefish see in 3-D, using the distance between their two eyes to generate depth perception like humans do. It was inspired by research in which praying mantises in 3-D glasses helped answer a similar question. The team’s results, published Wednesday in the journal Science Advances, suggest that, contrary to what scientists believed in the past, cuttlefish really can see in three dimensions. Octopuses and squid, despite being savvy hunters, don’t seem to have 3-D vision like ours. Previous work, more than 50 years ago, had found that one-eyed cuttlefish could still catch prey, suggesting they might be similar. But cuttlefish eyes often focus in concert when they’re hunting, and there is significant overlap in what each eye sees, a promising combination for generating 3-D vision. Dr. Wardill, Rachael Feord, a graduate student at the University of Cambridge, and the team decided to give the glasses a try during visits to the Marine Biological Lab in Woods Hole, Mass. The logic went like this: With each eye covered by a different colored lens, two different-colored versions of a scene, just slightly offset from each other, should pop out into a three-dimensional image. By playing a video on the tank wall of a scuttling pair of shrimp silhouettes, each a different color and separated from each other by varying amounts, the researchers could make a shrimp seem closer to the cuttlefish or farther away. If, that is, the cuttlefish experienced 3-D vision like ours. © 2020 The New York Times Company

Keyword: Vision; Evolution
Link ID: 26945 - Posted: 01.09.2020

Amber Dance The girl tried hard to hold her arms and hands steady, but her fingers wriggled and writhed. If she closed her eyes, the squirming got worse. It wasn’t that she lacked the strength to keep her limbs still — she just didn’t seem to have control over them. Carsten Bönnemann remembers examining the teenager at a hospital in Calgary, Canada, in 2013. As a paediatric neurologist with the US National Institute of Neurological Disorders and Stroke in Bethesda, Maryland, he often travelled to weigh in on puzzling cases. But he had never seen anything like this. If she wasn’t looking at her limbs, the girl didn’t seem to have any clue where they were. She lacked the sense of her body’s position in space, a crucial ability known as proprioception. “This is something that just doesn’t occur,” says Bönnemann. His team sequenced the girl’s genes, and those of another girl with similar symptoms1, and found mutations in a gene called PIEZO2. Their timing was fortunate: just a few years earlier, researchers looking for the mechanisms that cells use to sense touch had found that the gene encoded a pressure-sensitive protein2. The discovery of Piezo2 and a related protein, Piezo1, was a high point in a decades-long search for the mechanisms that control the sense of touch. The Piezos are ion channels — gates in the cell membrane that allow ions to pass through — that are sensitive to tension. “We’ve learned a lot about how cells communicate, and it’s almost always been about chemical signalling,” says Ardem Patapoutian, a molecular neurobiologist at Scripps Research in La Jolla, California, whose group identified the Piezos. “What we’re realizing now is that mechanical sensation, this physical force, is also a signalling mechanism, and very little is known about it.” © 2020 Springer Nature Limited

Keyword: Pain & Touch
Link ID: 26944 - Posted: 01.09.2020

By Elizabeth Brico The statistics are heartbreaking. Each year in the U.S., about 32,000 newborns are diagnosed with neonatal abstinence syndrome, a form of withdrawal that can result from in utero exposure to a number of drugs taken by the mother during pregnancy. Opioids — both prescribed and illegal — are among the most common culprits. These medications can be necessary, even life-saving, but that doesn’t make the resultant NAS any easier to watch: Newborns who suffer from the syndrome may exhibit tremors, irritability, hyperactive reflexes, high-pitched crying, and other symptoms. But drugs are not solely to blame for the prolonged suffering many of these infants experience. The way NAS cases are handled also has a profound impact on their severity, and often leads to negative outcomes. Health care providers and law enforcement authorities have historically separated these fragile babies from their mothers, doling out severe punishments to the latter. Although there is a growing awareness that change is needed, many hospitals still use outdated approaches — and child welfare agencies are particularly behind the times in this arena. Recent studies suggest that policies that place blame on mothers only heighten a newborn’s suffering by preventing infants from accessing potent care for reducing withdrawal symptoms: contact with mom. Misperceptions about opioid addiction, dependency, and NAS are woven into the very fabric of U.S. and state law. In order to receive federal funding for child abuse prevention, health care workers are required to report substance-affected newborns to Child Protective Services. Additionally, states can require health care providers to report or test for drug exposure during pregnancy. In many cases, mothers are reported even if the exposure is the result of prescribed methadone or buprenorphine — opioid-based drugs commonly used to treat addiction.

Keyword: Drug Abuse; Development of the Brain
Link ID: 26943 - Posted: 01.09.2020

Emily Makowski Bruce McEwen, a neuroendocrinologist at Rockefeller University, died January 2 after a brief illness. He was 81 years old. McEwen is best known for his research on how stress hormones can reconfigure neural connections in the brain, according to a university statement. In 1968, McEwen and his colleagues discovered that the rat hippocampus is affected by the hormone cortisol, sparking further research into how hormones can enter the brain and affect mental functioning and mood. At the time, most scientists believed that the brain was not malleable after becoming fully developed, a line of thinking that McEwen’s research findings contradicted. In 1993, he coined the term allostatic load, which describes the physiological effects of chronic stress. With his wife, Karen Bulloch, a Rockefeller professor, he studied how immune cells in the brain increase during a person’s lifespan and can contribute to neurodegenerative disease. He also researched how sex hormones affect the central nervous system. Over the course of his career, which spanned six decades, McEwen received many accolades including the Pasarow Foundation award in neuropsychiatry, the Fondation Ipsen Neuronal Plasticity and Endocrine Regulation prizes, the Scolnick Prize in Neuroscience, and the William James Lifetime Achievement Award for Basic Research. He was a member of the National Academy of Sciences, the National Academy of Medicine, and the American Society of Arts and Sciences. “Bruce was a giant in the field of neuroendocrinology,” McEwen’s colleague Leslie Vosshall, a neuroscientist at Rockefeller, says in the statement. “He was a world leader in studying the impact of stress hormones on the brain, and led by example to show that great scientists can also be humble, gentle, and generous human beings.” © 1986–2020 The Scientist

Keyword: Stress; Hormones & Behavior
Link ID: 26942 - Posted: 01.09.2020

By Rodrigo Pérez Ortega Nearly 2600 years ago, a man was beheaded near modern-day York, U.K.—for what reasons, we still don’t know—and his head was quickly buried in the clay-rich mud. When researchers found his skull in 2008, they were startled to find that his brain tissue, which normally rots rapidly after death, had survived for millennia—even maintaining features such as folds and grooves (above). Now, researchers think they know why. Using several molecular techniques to examine the remaining tissue, the researchers figured out that two structural proteins—which act as the “skeletons” of neurons and astrocytes—were more tightly packed in the ancient brain. In a yearlong experiment, they found that these aggregated proteins were also more stable than those in modern-day brains. In fact, the ancient protein clumps may have helped preserve the structure of the soft tissue for ages, the researchers report today in the Journal of the Royal Society Interface. Aggregated proteins are a hallmark of aging and brain diseases like Alzheimer’s. But the team didn’t find any protein clumps typical of those conditions in the ancient brain. The scientists still aren’t sure what made the proteins aggregate, but they suspect it could have something to do with the burial conditions, which appeared to take place as part of a ritual. In the meantime, the new findings could help researchers gather information from proteins of other ancient tissues from which DNA cannot be easily recovered. © 2019 American Association for the Advancement of Science

Keyword: Brain imaging; Glia
Link ID: 26941 - Posted: 01.09.2020

By Perri Klass, M.D. In December, the American Academy of Pediatrics put out a new clinical report on autism, an extensive document with an enormous list of references, summarizing 12 years of intense research and clinical activity. During this time, the diagnostic categories changed — Asperger’s syndrome and pervasive developmental disorder, diagnostic categories that once included many children, are no longer used, and we now consider all these children (and adults) to have autism spectrum disorder, or A.S.D. The salient diagnostic characteristics of A.S.D. are persistent problems with social communication, including problems with conversation, with nonverbal communication and social cues, and with relationships, together with restricted repetitive behavior patterns, including repetitive movements, rigid routines, fixated interests and sensory differences. Dr. Susan Hyman, the lead author on the new report, who is the division chief of developmental and behavioral pediatrics at Golisano Children’s Hospital at the University of Rochester, said in an email that much has changed over the past 12 years. She pointed in particular to increased medical awareness and understanding of conditions that often occur together with A.S.D., and to a greater emphasis on planning — together with families — how to support children as they grow. Dr. Susan E. Levy, a co-author of the statement who is a developmental behavioral pediatrician at Children’s Hospital of Philadelphia, said that one key message of the report is the emphasis on early identification and referral for treatment, even if a diagnosis of autism is suspected but not yet confirmed. The outcomes are better when treatment starts as early as possible, she said. The average age of diagnosis is now around 4 years, but the goal is to get it well under 2, she said. And children who are at higher risk — for example, those whose siblings have A.S.D. — should receive especially close screening and attention. © 2020 The New York Times Company

Keyword: Autism
Link ID: 26940 - Posted: 01.07.2020

By Brooke Siem The prescriptions began in the wake of my father’s sudden death when I was 15: Wellbutrin XL and Effexor XR for anxiety and depression, two separate doses of Synthroid to right a low-functioning thyroid, a morning and nighttime dose of tetracycline for acne, birth control to regulate the unpleasant side effects of womanhood, and four doses of Sucralfate to be taken at each meal and before bedtime — all given to me by the time I was old enough to vote. My general practitioner asked what Sucralfate was after I’d finished rattling off my prescriptive party mix during our first appointment. I was 22 and a recent Manhattan transplant. I had an apartment in Murray Hill and a job waiting tables at a local Italian restaurant. “It’s for something called bile reflux disease,” I said. “I used to randomly puke up bile all the time.” “Huh. Never heard of it.” He ripped off a completed prescription slip and scribbled across the new blank page. “You should really get the prescription for antidepressants from a psychiatrist, but I’ll give it to you along with all the rest since you’ve been on it for so long. And whenever you come back, maybe we should do a physical.” At the time, it never occurred to me that my medication needed monitoring or that perhaps my doctor should do a physical before sending me to the pharmacy. Not only was this five-minute exchange routine, but at no point during my years in the American mental health system did a psychiatrist, psychologist, doctor or pharmacist suggest that I consider reevaluating the decision to take antidepressants. Therefore, I believed that my only choices were to cope with depression or cope with antidepressants, and that depression would always thump inside me with the regularity of my own pulse.

Keyword: Depression; Drug Abuse
Link ID: 26939 - Posted: 01.07.2020

By Matthew Hutson When you are stuck on a problem, sometimes it is best to stop thinking about it—consciously, anyway. Research has shown that taking a break or a nap can help the brain create pathways to a solution. Now a new study expands on the effect of this so-called incubation by using sound cues to focus the sleeping mind on a targeted problem. When humans sleep, parts of the brain replay certain memories, strengthening and transforming them. About a decade ago researchers developed a technique, called targeted memory reactivation (TMR), aimed at further reinforcing selected memories: when a sound becomes associated with a memory and is later played during sleep, that memory gets reactivated. In a study published last November in Psychological Science, scientists tested whether revisiting the memory of a puzzle during sleep might also improve problem-solving. About 60 participants visited the laboratory before and after a night of sleep. In an evening session, they attempted spatial, verbal and conceptual puzzles, with a distinct music clip repeating in the background for each, until they had worked on six puzzles they could not solve. Overnight they wore electrodes to detect slow-wave sleep—slumber's deepest phase, which may be important for memory consolidation—and a device played the sounds assigned to three of the six unsolved puzzles. The next day, back at the lab, the participants attempted the six puzzles again. (Each repeated the experiment with a different set of puzzles the following night.) All told, the subjects solved 32 percent of the sound-prompted puzzles versus 21 percent of the untargeted puzzles—a boost of more than 50 percent. © 2020 Scientific American

Keyword: Sleep; Learning & Memory
Link ID: 26938 - Posted: 01.07.2020

Natalie C Tronson Ph.D. We all have a strong intuitive sense of what memory is: it’s the conscious recollection of events, people, and places from our past. And it’s something we often wish we were better at so we didn’t continuously lose our keys, forget where our car was parked, and we could remember more facts for exams, remember people’s birthdays, or what I came all the way upstairs to grab. But memory is so much more. Memory is also how I can find my way around the town I live in now—and how I can still find my way around the town I grew up in, despite the many changes over the 25 years since I left. It’s how I know how to drive the car, and how I can sing four verses of Mary Had a Little Lamb to my child sitting in the back seat demanding that I sing. It’s why I know to stop at the red light, go at the green, and avoid the stretch of road that has been under construction for the past six months. It’s also one reason why I feel anxious when pedestrians run across the street randomly, and why our cats come running home when they hear the front door of our house open. That’s a lot of different types of memory just for a quick drive home: memory for spatial learning, verbal memory for songs, motor learning for driving, and episodic memory, among others, are in there too. Not only are there a lot of different types of memory, but there is also a lot of real estate and energy in our brains (and in the brains of many other species) taken up for learning and memory processes. © 2020 Sussex Publishers, LLC

Keyword: Learning & Memory
Link ID: 26937 - Posted: 01.07.2020

By Jane E. Brody If you live with or work with someone who suffers from migraine, there’s something very important you should know: A migraine is not “just a headache,” as many seem to think. Nor is it something most sufferers can simply ignore and get on with their lives. And if you are a migraine sufferer, there’s something potentially life-changing that you should know: There are now a number of medications available that can either prevent or alleviate many attacks, as well as a newly marketed wearable nerve-stimulating device that can be activated by a smartphone to relieve the pain of migraine. Migraine is a neurological disorder characterized by recurrent attacks of severe, often incapacitating headache and dysfunction of the autonomic nervous system, which controls the body’s myriad automatic activities like digestion and breathing. The throbbing or pulsating pain of migraine is often accompanied by nausea and vomiting. Translation: Migraine is a headache, all right, but with body-wide effects because the brain converses with the rest of the body. It is often severe enough to exact a devastating toll on someone’s ability to work, interact with others, perform the tasks of daily life, or even be in a normal living environment. When in the throes of a migraine attack, sufferers may be unable to tolerate light, noise, smells or even touch. Dr. Stephen Silberstein, a neurologist at Thomas Jefferson University and director of the Jefferson Headache Center, told me “There are 47 million people in this country with migraine, and for six million, the condition is chronic, which means they have more than 15 headache days a month,” he said. “It’s time to destigmatize migraine and provide sufferers with effective treatment,” said Dr. David W. Dodick, neurologist at the Mayo Clinic in Scottsdale. “They’re not fakers, weak individuals who are trying to get out of work.” © 2020 The New York Times Company

Keyword: Pain & Touch
Link ID: 26936 - Posted: 01.07.2020

By James Gallagher Health and science correspondent An early life full of neglect, deprivation and adversity leads to people growing up with smaller brains, a study suggests. The researchers at King's College London were following adopted children who spent time in "hellhole" Romanian orphanages. They grew up with brains 8.6% smaller than other adoptees. The researchers said it was the "most compelling" evidence of the impact on the adult brain. The appalling care at the orphanages came to light after the fall of Romania's communist dictator Nicolae Ceausescu in 1989. "I remember TV pictures of those institutions, they were shocking," Prof Edmund Sonuga-Barke, who now leads the study following those children, told the BBC. He described the institutions as "hellholes" where children were "chained into their cots, rocking, filthy and emaciated". The children were physically and psychologically deprived with little social contact, no toys and often ravaged by disease. The children studied had spent between two weeks and nearly four years in such institutions. Previous studies on children who were later adopted by loving families in the UK showed they were still experiencing mental health problems in adulthood. Higher levels of traits including autism, attention deficit hyperactivity disorder (ADHD) and a lack of fear of strangers (disinhibited social engagement disorder) have all been documented. The latest study, published in Proceedings of the National Academy of Sciences, is the first to scan the brains for answers. There were 67 Romanian adoptees in the study and their brains were compared to 21 adoptees who did not suffer early life deprivation. "What we found is really quite striking," Prof Sonuga-Barke told the BBC. First the total brain volume - the size of the brain - was 8.6% smaller in the Romanian adoptees on average. And the longer they spent in the Romanian orphanages, the greater the reduction in brain size. © 2020 BBC.

Keyword: Development of the Brain; Stress
Link ID: 26935 - Posted: 01.07.2020

Ryan F. Mandelbaum Scientists have uncovered a new kind of electrical process in the human brain that could play a key role in the unique way our brains compute. Our brains are computers that work using a system of connected brain cells, called neurons, that exchange information using chemical and electric signals called action potentials. Researchers have discovered that certain cells in the human cortex, the outer layer of the brain, transmit signals in a way not seen in corresponding rodent cells. This process might be important to better understanding our unique brains and to improving programs that are based on a model of the human brain. “Human neurons may be more powerful computational devices than previously thought,” study corresponding author Matthew Larkum at Humboldt University of Berlin told Gizmodo in an email. Human brains have a thick cortex, especially the second and third layers (L2/3) from the surface. These layers contain brain cells with lots of branches, called dendrites, that connect them to and exchange information with other brain cells. The researchers acquired and analyzed slices of L2/3 tissue from patients with epilepsy and tumors, focusing specifically on these dendrites. Larkum explained via email that epilepsy surgeries provided a sufficient amount of available cortex tissue, while the tumor patient tissue was used to ensure that the observations weren’t unique to people with epilepsy. The team hooked the tissues to a patch clamp—essentially a system that constructs an electrical circuit from the cells and a measurement instrument—and used fluorescing microscope to observe the action of these L2/3 cells. The team noticed that inputted electrical currents ignited more action potentials than they would in rodent cells and that a chemical that should have blocked the dendrites’ activity did not completely do so. © 2020 G/O Media Inc.

Keyword: Learning & Memory
Link ID: 26934 - Posted: 01.04.2020

By Simon Makin For many people battling addictions, seeing drug paraphernalia—or even places associated with past use—can ignite cravings that make relapse more likely. Associating environmental cues with pleasurable experiences is a basic form of learning, but some researchers think such associations can “hijack” behavior, contributing to problems such as addiction and eating disorders. Researchers led by neuroscientist Shelly Flagel of the University of Michigan have found a brain circuit that may control this hijacking; rats that exhibit a type of compulsive behavior show different brain connectivity and activity than those that do not, and manipulation of the circuit altered their behavior. These findings may help researchers understand why some individuals are more susceptible to impulse-control disorders. “This is technically a really excellent study,” says neuroscientist Jeff Dalley of the University of Cambridge, who was not involved in the work. In the study, published last September in eLife, researchers showed rats an inert lever shortly before delivering a tasty treat via a chute, then sorted them into groups based on their responses. All rats learned to associate the lever with the treat, but some—dubbed “goal trackers”—began to approach the food chute directly after seeing the lever, whereas inherent “sign trackers” kept compulsively returning to the lever itself. The team suspected that two brain regions were involved: the paraventricular nucleus of the thalamus (PVT), which drives behavior, and the prelimbic cortex, which is involved in reward learning. The researchers used a technique called chemogenetics to alter neurons in the circuit connecting these regions, which let them turn on or inhibit signals from the prelimbic cortex using drugs. Activating the circuit reduced sign trackers' tendency to approach the lever but did not affect goal trackers. Deactivating it drew goal trackers to the lever (sign-tracking behavior), without affecting preexisting sign trackers. The team also found increased dopamine, a chemical messenger involved in reward processing, in the newly sign-tracking brains. © 2020 Scientific American

Keyword: Drug Abuse
Link ID: 26933 - Posted: 01.04.2020

By Sharon Jayson AUSTIN, Texas — Retired state employees Vickey Benford, 63, and Joan Caldwell, 61, are Golden Rollers, a group of the over-50 set that gets out on assorted bikes — including trikes for adults they call “three wheels of awesome” — for an hour of trail riding and camaraderie. “I love to exercise, and I like to stay fit,” said Caldwell, who tried out a recumbent bike, a low-impact option that can be easier on the back. “It keeps me young.” Benford encouraged Caldwell to join the organized rides, which have attracted more than 225 riders at city rec centers and senior activity centers. The cyclists can choose from a small, donated fleet of recumbent bikes, tandem recumbents and tricycles. “With seniors, it’s less about transportation and more about access to the outdoors, social engagement and quality of life,” said Christopher Stanton, whose idea for Golden Rollers grew out of the Ghisallo Cycling Initiative, a youth biking nonprofit he founded in 2011. But that’s not all, according to brain scientists. They point to another important benefit: Exercising both body and brain can help people stay healthier longer. The new thinking about aging considers not just how long one lives, but how vibrant one stays later in life. “If you’re living, you want to be living well,” said Tim Peterson, an assistant professor of internal medicine at the Washington University School of Medicine in St. Louis. “Most people who were interested in life span and were studying genes — which control life span — switched to ‘healthspan.’” “Healthspan,” a coinage now gaining traction, refers to the years that a person can expect to live in generally good health — free of chronic illnesses and cognitive decline that can emerge near life’s end. Although there’s only so much a person can do to delay the onset of disease, there’s plenty that scientists are learning to improve your chances of a better healthspan. © 2020 Kaiser Family Foundation

Keyword: Development of the Brain
Link ID: 26932 - Posted: 01.04.2020

Jerold Chun, M.D., Ph.D. Alzheimer’s disease (AD) is the most common cause of dementia, currently affecting an estimated 5.8 million Americans. It has been over a century since AD was first described, but it is still not sufficiently well understood to enable development of drugs to treat it. As lifespan continues to rise and for myriad other reasons, the number of AD cases per state in the US is predicted to increase 12 to 43 percent over the next five years. The lack of disease-modifying treatments may reflect a feature of AD pathology that was first noted in its initial description: the vast heterogeneity of the hallmark “senile plaques” that are found in all AD brains. When Alois Alzheimer and Oskar Fischer described the first cases of AD, they noted plaque accumulations of a protein called amyloid that builds up in between brain cells and interrupts cell-to-cell communication; amyloid plaques vary in size, shape, abundance, and location within the brain. “Among the plaques in the cerebral cortex many were of an extraordinary size, such as I have never seen,” Alois Alzheimer stated. “Some evidently arose from the fusion of smaller ones since they contained several central cores, but others had one exceptionally big central core and uncommonly large halo.” Disease heterogeneity extends to behavior and includes varying age of onset, symptoms, and disease progression. Some variability may be explained by genetic heterogeneity, since more than 33 AD risk factor genes have been identified via a technique called “genome wide association studies” (GWAS), which broadly samples DNA from cells outside of the brain to identify mutations that are present in every cell of the body. None of these genes, however, are considered to cause AD. © 2020 The Dana Foundation

Keyword: Alzheimers; Genes & Behavior
Link ID: 26931 - Posted: 01.04.2020

By Knvul Sheikh When researchers began tinkering with a class of tranquilizer drugs called benzodiazepines in the 1950s, they felt they had uncovered a solution to modern anxiety and insomnia. Benzodiazepines worked quickly and effectively to quell racing heartbeats and dismiss spinning thoughts. The dozen or so different types — including Xanax, Valium, Ativan and Klonopin — became the most frequently prescribed drugs around the world, even as concerns arose about their potential side effects and addictive properties. “Patients themselves, and not the medical profession, were the first to realize that long-term use of benzodiazepines can cause problems,” wrote Dr. Heather Ashton, a British psychopharmacologist. She said that patients who had been on the medications for months or years would come to her with fears that the drugs were making them more ill. Some continued to have symptoms of depression or anxiety. Others had developed muscle weakness, memory lapses, or heart or digestive issues. Dr. Ashton would dedicate much of her career to listening to hundreds of patients’ experiences and rigorously collecting data. The result of her work, in 1999, was “Benzodiazepines: How They Work And How To Withdraw.” Now known simply as “The Ashton Manual,” it has become a cornerstone for those looking to quit the drugs safely. Addiction researchers worldwide still cite it in studies on benzodiazepines. And patient support groups have translated and distributed it in about a dozen languages. Dr. Ashton died on Sept. 15, 2019, at her home in Newcastle upon Tyne, England. She was 90. Her death, which had not been widely reported, was confirmed by her son John. Image“Benzodiazepines: How They Work and How to Withdraw,” better known as “The Ashton Manual,” has become a cornerstone for those looking to quit anxiety drugs safely. © 2020 The New York Times Company

Keyword: Drug Abuse
Link ID: 26930 - Posted: 01.04.2020