Michael Marshall One treatment for survivors of COVID-19 who have lost their sense of smell is 'smell training', in which they relearn prescribed scents, such as those of roses and lemons.Credit: Christine E. Kelly Early in the COVID-19 pandemic, it emerged that many people infected with the SARS-CoV-2 virus were losing their sense of smell — even without displaying other symptoms. Researchers also discovered that infected people could lose their sense of taste and their ability to detect chemically triggered sensations such as spiciness, called chemesthesis. Almost a year later, some still haven’t recovered these senses, and for a proportion of people who have, odours are now warped: unpleasant scents have taken the place of normally delightful ones. Nature surveys the science behind this potentially long-lasting and debilitating phenomenon. How many people with COVID-19 lose their sense of smell? The exact percentage varies between studies, but most suggest that smell loss is a common symptom. One review published last June1 compiled data from 8,438 people with COVID-19, and found that 41% had reported experiencing smell loss. In another study, published in August2, a team led by researcher Shima T. Moein at the Institute for Research in Fundamental Sciences in Tehran, Iran, administered a smell-identification test to 100 people with COVID-19 in which the subjects sniffed odours and identified them on a multiple-choice basis. Ninety-six per cent of the participants had some olfactory dysfunction, and 18% had total smell loss (otherwise known as anosmia). © 2021 Springer Nature Limited

Keyword: Chemical Senses (Smell & Taste)
Link ID: 27649 - Posted: 01.15.2021

By Gina Kolata In a small clinical trial, an experimental Alzheimer’s drug slowed the rate at which patients lost the ability to think and care for themselves, the drug maker Eli Lilly announced on Monday. The findings have not been published in any form, and not been widely reviewed by other researchers. If accurate, it is the first time a positive result has been found in a so-called Phase 2 study, said Dr. Lon S. Schneider, professor of psychiatry, neurology and gerontology at the University of Southern California. Other experimental drugs against Alzheimer’s were never tested in Phase 2 trials, moving straight to larger Phase 3 trials, or failed to produce positive results. The Phase 3 studies themselves have repeatedly had disappointing results. The two-year study involved 272 patients with brain scans indicative of Alzheimer’s disease. Their symptoms ranged from mild to moderate. The drug, donanemab, a monoclonal antibody, binds to a small part of the hard plaques in the brain made of a protein, amyloid, that are hallmarks of Alzheimer’s disease. Patients received the drug by infusion every four weeks. Participants who received the drug had a 32 percent deceleration in the rate of decline, compared with those who got a placebo. In six to 12 months, plaques were gone and stayed gone, said Dr. Daniel Skovronsky, the company’s chief scientific officer. At that point, patients stopped getting the drug — they got a placebo instead — for the duration of the study. The small study needs to be replicated, noted Dr. Michael Weiner, a leading Alzheimer’s researcher at the University of California, San Francisco. Still, “this is big news,” he said. “This holds out hope for patients and their families.” Eli Lilly did not release the sort of pertinent data needed for a thorough analysis, Dr. Schneider said. For example, the company provided only percentages describing declines in function among the participants, not the actual numbers. © 2021 The New York Times Company

Keyword: Alzheimers
Link ID: 27648 - Posted: 01.15.2021

By Jonathan Lambert One Volta’s electric eel — able to subdue small fish with an 860-volt jolt — is scary enough. Now imagine over 100 eels swirling about, unleashing coordinated electric attacks. Such a sight was assumed to be only the stuff of nightmares, at least for prey. Researchers have long thought that these eels, a type of knifefish, are solitary, nocturnal hunters that use their electric sense to find smaller fish as they sleep (SN: 12/4/14). But in a remote region of the Amazon, groups of over 100 electric eels (Electrophorus voltai) hunt together, corralling thousands of smaller fish together to concentrate, shock and devour the prey, researchers report January 14 in Ecology and Evolution. “This is hugely unexpected,” says Raimundo Nonato Mendes-Júnior, a biologist at the Chico Mendes Institute for Biodiversity Conservation in Brasilia, Brazil who wasn’t involved in the study. “It goes to show how very, very little we know about how electric eels behave in the wild.” Group hunting is quite rare in fishes, says Carlos David de Santana, an evolutionary biologist at the Smithsonian’s National Museum of Natural History in Washington, D.C. “I’d never even seen more than 12 electric eels together in the field,” he says. That’s why he was stunned in 2012 when his colleague Douglas Bastos, now a biologist at the National Institute of Amazonian Research in Manaus, Brazil, reported seeing more than 100 eels congregating and seemingly hunting together in a small lake in northern Brazil. © Society for Science & the Public 2000–2021.

Keyword: Evolution
Link ID: 27647 - Posted: 01.15.2021

Kayt Sukel Psychedelic drugs conjure images of tie-dyed tee shirts, Woodstock, and Vietnam War protests. While early research into the properties of drugs like psilocybin (magic mushrooms) and lysergic acid diethylamide (LSD) during the middle of the 20th century suggested therapeutic potential for diverse mental health conditions, their role in the 1960s anti-war and counterculture movement made them suspect by law enforcement. Not long after American psychologist Timothy Leary called for people to “turn on, tune in, and drop out,” endorsing the regular use of psychedelic drugs for health and well-being, the federal Controlled Substances Act classified them as highly dangerous Schedule 1 compounds, or drugs with “no currently accepted medical use and a high potential for abuse.” “Initially, psychedelics showed quite a lot of promise for treating a wide range of mental health conditions—in particular, addiction and post-traumatic stress disorder (PTSD),” says Anil Seth, co-director of the Sackler Centre for Consciousness Science at the University of Sussex in the United Kingdom. “There’s long been a blame game going regarding what led to these drugs being outlawed, mostly focusing on people like Timothy Leary promoting indiscriminate use of what we know are quite powerful drugs. But the end result was that, despite their promise, it became nearly impossible for anyone to do any research at all on them.” Over the past decade, however, there has been a revival of psychopharmacology and neuroscience research into the effects of psychedelic drugs. In fact, despite continuing legal barriers and funding challenges involved with using these banned drugs in research studies—many researchers wait years for Food and Drug Administration approvals and require funding from non-governmental agencies to move forward—several unique research centers, including the Centre for Psychedelic Research at Imperial College London and Johns Hopkins University’s Center for Psychedelics and Consciousness Research, are now actively studying LSD, psilocybin, and dimethyltryptamine (DMT), from both basic science and clinical perspectives. © 2021 The Dana Foundation

Keyword: Depression; Drug Abuse
Link ID: 27646 - Posted: 01.15.2021

Dana G Smith This is a modified excerpt from Inside Your Head 🧠, a weekly newsletter exploring why your brain makes you think, feel, and act the way you do, written by me, Elemental’s senior writer and a former brain scientist. Subscribe here so you won’t miss the next one. Last Wednesday was a dark day for the United States. I’m obviously not a political reporter, so I’m not going to talk about security breaches or the future of our democracy or just how terrifying and disgraceful what happened at the Capitol was (you should check out our sister publication GEN for those types of stories). But I am going to discuss what might have been going on in the brains of those who attempted the insurrection. Hatred and violence toward another group of people is an extension — and perversion — of our natural human tendency to classify “us” from “them.” Evolutionarily, group membership and the cooperation it facilitates was essential for human survival. Our species forms alliances easily, sometimes based on genetic or familial ties but sometimes more arbitrarily. Take affinity for a certain sports team; it says nothing about a person’s qualities and offers no real benefits, and yet people have literally killed opposing team’s fans. In-group/out-group categorizations are made almost instantaneously in the brain and, when paired with negative stereotypes, can result in feelings of fear, disgust, and dehumanization. Studies have shown that viewing pictures of people from a different race, for example, activates the amygdala — a brain region strongly implicated in fear.

Keyword: Emotions
Link ID: 27645 - Posted: 01.15.2021

by Sarah DeWeerdt Children with autism may have a subtly different set of bacteria in their gut than their non-autistic siblings, according to unpublished data presented virtually on Tuesday at the 2021 Society for Neuroscience Global Connectome. The prospect that manipulating the microbiome could ease gastrointestinal problems and other autism traits has tantalized many families of autistic children. But studies of the gut microbiome in people with autism are scarce and have shown conflicting results, and mouse studies can be difficult to interpret. For the new work, researchers recruited 111 families that each have two children — one with autism and one without — born within two years of each other and aged 2 to 7 years old. “We tried to be as careful as possible by using a control cohort that were siblings,” says study leader Maude David, assistant professor of microbiology at Oregon State University in Corvallis. This study design helped control for variables such as household environment, pets and other factors that can shape the microbiome, she says. The researchers collected stool samples from the children at three time points, two weeks apart. The repeated sampling reduced the likelihood that short-term shifts in the children’s gut microbiome — due to transient environmental influences, such as day-to-day dietary changes — would skew the results. © 2021 Simons Foundation

Keyword: Autism
Link ID: 27644 - Posted: 01.15.2021

By Nicholas Bakalar People who consume a diet rich in vitamins C and E may be at reduced risk for Parkinson’s disease. Researchers followed 41,058 Swedish men and women for an average of 18 years, gathering data on their health and diet. They assessed intake of vitamins C and E as well as beta-carotene and a measure called NEAC, which takes into account all antioxidants from food and their interactions with each other. Over the course of the study, published in Neurology, there were 465 cases of Parkinson’s disease. After adjusting for age, sex, B.M.I., education, smoking, alcohol consumption and other characteristics, they found that compared with the one-third of people with the lowest intake of vitamin C or E, the one-third with the highest intake had a 32 percent reduced risk for Parkinson’s disease. Those in the highest one-third in consumption of both vitamins together had a 38 percent reduced risk. There was no effect for beta-carotene or the NEAC measure. The lead author, Essi Hantikainen, who was a researcher at the University of Milano-Bicocca when the work was done, said that more research needs to be done before drawing definitive conclusions or offering advice about diet or supplement use and the risk of Parkinson’s. Still, she said, “Implementation of a diet that includes foods rich in vitamins C and E might help protect against the development of Parkinson’s later in life. In any case, it’s never wrong to implement a healthy diet.” © 2021 The New York Times Company

Keyword: Parkinsons
Link ID: 27643 - Posted: 01.15.2021

By Roni Caryn Rabin Until March, when everything started tasting like cardboard, Katherine Hansen had such a keen sense of smell that she could recreate almost any restaurant dish at home without the recipe, just by recalling the scents and flavors. Then the coronavirus arrived. One of Ms. Hansen’s first symptoms was a loss of smell, and then of taste. Ms. Hansen still cannot taste food, and says she can’t even tolerate chewing it. Now she lives mostly on soups and shakes. “I’m like someone who loses their eyesight as an adult,” said Ms. Hansen, a realtor who lives outside Seattle. “They know what something should look like. I know what it should taste like, but I can’t get there.” A diminished sense of smell, called anosmia, has emerged as one of the telltale symptoms of Covid-19, the illness caused by the coronavirus. It is the first symptom for some patients, and sometimes the only one. Often accompanied by an inability to taste, anosmia occurs abruptly and dramatically in these patients, almost as if a switch had been flipped. Most regain their senses of smell and taste after they recover, usually within weeks. But in a minority of patients like Ms. Hansen, the loss persists, and doctors cannot say when or if the senses will return. Scientists know little about how the virus causes persistent anosmia or how to cure it. But cases are piling up as the coronavirus sweeps across the world, and some experts fear that the pandemic may leave huge numbers of people with a permanent loss of smell and taste. The prospect has set off an urgent scramble among researchers to learn more about why patients are losing these essential senses, and how to help them. “Many people have been doing olfactory research for decades and getting little attention,” said Dr. Dolores Malaspina, professor of psychiatry, neuroscience, genetics and genomics at Icahn School of Medicine at Mount Sinai in New York. “Covid is just turning that field upside down.” © 2021 The New York Times Company

Keyword: Chemical Senses (Smell & Taste)
Link ID: 27642 - Posted: 01.09.2021

Our staff took a look back at the papers we wrote about in 2020 that most shaped our understanding of autism and how to diagnose or treat it. Despite the chaos of this year, there were many to consider. But we reviewed them all, asked some researchers for input and winnowed the list down to 10. Some of our selections highlight new insights into factors that influence autism traits, including fever, mitochondria and exons — the protein-coding parts of genes. Others expand our understanding of the genes and genetic regions linked to autism, as well as their roles in related conditions. Two new gene therapies for autism-related syndromes also caught our eye. And we single out a study of the sperm from men who have children on the spectrum, and a look at what happens to the toddlers who screen positive for autism. Here are our picks for the past year’s most notable papers, in reverse chronological order. DNA helix1. Mutations in the same exon linked to similar autism traits People with autism who carry DNA variants in the same exon, or protein-coding region of a gene, have more similar cognitive abilities and behaviors than those who carry mutations in different regions of the same gene, this study found. A separate study detailed how one particular exon contributes to social behavior and cognitive abilities in mice; a third paper described a new tool that helps researchers determine how mutations in an exon affect the number of protein isoforms a gene can express. © 2021 Simons Foundation

Keyword: Autism; Genes & Behavior
Link ID: 27641 - Posted: 01.09.2021

By Elizabeth Pennisi Hammer a nail into a tree, and it will get stuck. So why doesn’t the same thing happen to the sharp beaks of woodpeckers? Scientists say they finally have the answer. In a new study, researchers took high-speed videos of two black woodpeckers (Dryocopus martius) pecking away at hardwood trunks in zoos and analyzed them frame by frame to see how the head and beak moved throughout each peck. The bird’s secret: an ability to move its upper and lower beaks independently, the team reports this week at the virtual annual meeting of the Society for Integrative and Comparative Biology. Once the tip of the woodpecker’s bill hits the wood, the bird’s head rotates to the side ever so slightly, lifting the top part of the beak and twisting it a bit in the other direction, the videos reveal. This pull opens the bill a tiny amount and creates free space between the beak tip and the wood at the bottom of the punctured hole, so the bird can then easily retract its beak. Until now, scientists have thought woodpecker bills would need to be rigidly attached to the skull to successfully drill into the wood to find insect prey. But actually, the bill’s flexibility in these joints ensures that the bird’s signature “rat-a-tat-tat” doesn’t stop at “rat.” © 2021 American Association for the Advancement of Science.

Keyword: Brain Injury/Concussion; Evolution
Link ID: 27640 - Posted: 01.09.2021

By Pam Belluck Almost immediately, Dr. Hisam Goueli could tell that the patient who came to his psychiatric hospital on Long Island this summer was unusual. The patient, a 42-year-old physical therapist and mother of four young children, had never had psychiatric symptoms or any family history of mental illness. Yet there she was, sitting at a table in a beige-walled room at South Oaks Hospital in Amityville, N.Y., sobbing and saying that she kept seeing her children, ages 2 to 10, being gruesomely murdered and that she herself had crafted plans to kill them. “It was like she was experiencing a movie, like ‘Kill Bill,’” Dr. Goueli, a psychiatrist, said. The patient described one of her children being run over by a truck and another decapitated. “It’s a horrifying thing that here’s this well-accomplished woman and she’s like ‘I love my kids, and I don’t know why I feel this way that I want to decapitate them,’” he said. The only notable thing about her medical history was that the woman, who declined to be interviewed but allowed Dr. Goueli to describe her case, had become infected with the coronavirus in the spring. She had experienced only mild physical symptoms from the virus, but, months later, she heard a voice that first told her to kill herself and then told her to kill her children. At South Oaks, which has an inpatient psychiatric treatment program for Covid-19 patients, Dr. Goueli was unsure whether the coronavirus was connected to the woman’s psychological symptoms. “Maybe this is Covid-related, maybe it’s not,” he recalled thinking. “But then,” he said, “we saw a second case, a third case and a fourth case, and we’re like, ‘There’s something happening.’” Indeed, doctors are reporting similar cases across the country and around the world. A small number of Covid patients who had never experienced mental health problems are developing severe psychotic symptoms weeks after contracting the coronavirus. In interviews and scientific articles, doctors described: A 36-year-old nursing home employee in North Carolina who became so paranoid that she believed her three children would be kidnapped and, to save them, tried to pass them through a fast-food restaurant’s drive-through window. © 2020 The New York Times Company

Keyword: Schizophrenia
Link ID: 27639 - Posted: 12.31.2020

David Eagleman When he was two years old, Ben stopped seeing out of his left eye. His mother took him to the doctor and soon discovered he had retinal cancer in both eyes. After chemotherapy and radiation failed, surgeons removed both his eyes. For Ben, vision was gone forever. But by the time he was seven years old, he had devised a technique for decoding the world around him: he clicked with his mouth and listened for the returning echoes. This method enabled Ben to determine the locations of open doorways, people, parked cars, garbage cans, and so on. He was echolocating: bouncing his sound waves off objects in the environment and catching the reflections to build a mental model of his surroundings. Echolocation may sound like an improbable feat for a human, but thousands of blind people have perfected this skill, just like Ben did. The phenomenon has been written about since at least the 1940s, when the word “echolocation” was first coined in a Science article titled “Echolocation by Blind Men, Bats, and Radar.” How could blindness give rise to the stunning ability to understand the surroundings with one’s ears? The answer lies in a gift bestowed on the brain by evolution: tremendous adaptability. Whenever we learn something new, pick up a new skill, or modify our habits, the physical structure of our brain changes. Neurons, the cells responsible for rapidly processing information in the brain, are interconnected by the thousands—but like friendships in a community, the connections between them constantly change: strengthening, weakening, and finding new partners. The field of neuroscience calls this phenomenon “brain plasticity,” referring to the ability of the brain, like plastic, to assume new shapes and hold them. More recent discoveries in neuroscience suggest that the brain’s brand of flexibility is far more nuanced than holding onto a shape, though. To capture this, we refer to the brain’s plasticity as “livewiring” to spotlight how this vast system of 86 billion neurons and 0.2 quadrillion connections rewires itself every moment of your life.

Keyword: Sleep
Link ID: 27638 - Posted: 12.31.2020

By Veronique Greenwood Zipping through water like shimmering arrowheads, cuttlefish are swift, sure hunters — death on eight limbs and two waving tentacles for small creatures in their vicinity. They morph to match the landscape, shifting between a variety of hues and even textures, using tiny structures that expand and contract beneath their skin. They even seem to have depth perception, researchers using tiny 3-D vision glasses found, placing them apart from octopuses and squids. And their accuracy at striking prey is remarkable. But for cuttlefish, these physical feats in pursuit of food are not the whole story. A new study published this month in the journal Royal Society Open Science shows that there is even more to cuttlefish cognition than scientists may have known. The sea creatures appear to be capable of performing calculations that are more complicated than simply “more food is better.” Presented with a choice between one shrimp or two, they will actually choose the single shrimp when they have learned through experience that they are rewarded for this choice. While the braininess of their octopus cousins gets a lot of attention, researchers who study animal cognition have uncovered surprising talents in cuttlefish over the years. For instance, the cephalopods will hunt fewer crabs during the day if they learn that shrimp, their preferred food, is predictably available during the night. That shows that they can think ahead. Chuan-Chin Chiao, a biologist at National Tsing Hua University in Taiwan, and an author of the current paper alongside his colleague Tzu-Hsin Kuo, has found in the past that cuttlefish that are hungry will choose a bigger, harder-to-catch shrimp to attack, and those that are not will choose smaller, easier-to-catch ones. But researchers have also found that animals do not always make decisions that seem logical at first glance. Like humans, whose behavior rarely fits economists’ visions of what an ideal, rational creature would do, animals respond to their environments using learned experiences. © 2020 The New York Times Company

Keyword: Attention; Evolution
Link ID: 27637 - Posted: 12.31.2020

By Elizabeth Preston When Jessica Yorzinski chased great-tailed grackles across a field, it wasn’t a contest to see who blinked first. But she did want the birds to blink. Dr. Yorzinski had outfitted the grackles, which look a bit like crows but are in another family of birds, with head-mounted cameras pointing back at their faces. Like other birds, grackles blink sideways, flicking a semitransparent membrane across the eye. Recordings showed that the birds spent less time blinking during the riskiest parts of a flight. The finding was published Wednesday in Biology Letters. Dr. Yorzinski, a sensory ecologist at Texas A&M University, had been wondering how animals balance their need to blink with their need to get visual information about their environments. Humans, she said, “blink quite often, but when we do so we lose access to the world around us. It got me thinking about what might be happening in other species.” She worked with a company that builds eye-tracking equipment to make a custom bird-size headpiece. Because a bird’s eyes are on the sides of its head, the contraption held one video camera pointed at the left eye and one at the right, making the bird resemble a sports fan in a beer helmet. The headpiece was connected to a backpack holding a battery and transmitter. Dr. Yorzinski captured 10 wild great-tailed grackles, which are common in Texas, to wear this get-up. She used only male birds, which are big enough to carry the equipment without trouble. Each bird wore the camera helmet and backpack while Dr. Yorzinski encouraged it to fly by chasing it across an outdoor enclosure. © 2020 The New York Times Company

Keyword: Vision; Evolution
Link ID: 27636 - Posted: 12.22.2020

by Sarah DeWeerdt A drug that has been tested in clinical trials as a treatment for depression restores social memory in a mouse model of 22q11.2 deletion syndrome, according to a new study. The findings hint that the drug might also be useful to treat social cognitive difficulties in people with conditions such as autism, experts say. People who are missing one copy of a chromosomal region known as 22q11.2 have heart abnormalities, distinctive facial features and an increased risk of schizophrenia and other psychiatric conditions. About 16 percent have autism. People with the syndrome also have a smaller-than-average hippocampus, a structure that functions as the brain’s memory hub. The findings extend what researchers know about the role of the hippocampus in social behavior by suggesting that a small region of the hippocampus known as CA2 springs to life when an animal encounters an individual it hasn’t met before. A strength of the study is that it describes the basic biology of a brain circuit, shows how that circuit is disrupted in a mouse model and identifies a therapeutic target to reverse those disruptions, says Anthony LaMantia, professor of developmental disorders and genetics at Virginia Polytechnic Institute and State University in Blacksburg, who was not involved in the work. “This is one of the best papers sort of going from soup to nuts that has come out.” Previous studies showed that CA2 is crucial for social memory, the ability to recognize and remember others. “But we really didn’t have a good handle on what type of information CA2 was providing to the rest of the brain,” says study leader Steven Siegelbaum, professor of neuroscience and pharmacology at Columbia University. © 2020 Simons Foundation

Keyword: Autism; Genes & Behavior
Link ID: 27635 - Posted: 12.22.2020

Robin McKie, Science Editor Anne Abbott is a scientist on a mission. She believes large numbers of debilitating strokes can be prevented without surgical interventions. Lifestyle changes and medication alone can make massive improvements to people at risk from the thickening of their arteries. It is not an attitude that has endeared her to the medical establishment, however. For years, it has attempted to block her work while instead pressing for increasing use of carotid surgery and stents, she told the Observer last week. “I was told not to publish my research findings,” said Abbott, associate professor of neuroscience at Monash University in Melbourne. “I was shocked. Then it became hard to submit grant applications to continue my research. People would say ‘yes’ to my proposals, then at the last minute, they would back out. If you can’t put a grant in, it could be the end of your research career.” But now Abbott’s efforts have received global recognition – thanks to the judges of the John Maddox prize. Named after the former editor of Nature, and organised by the journal and the charity Sense About Science, the international awards are given to researchers who stand up for sound science. Past winners have included scientists who have been persecuted for speaking out about the dangers of rainforest destruction, the bleaching of coral reefs and the misuse of vitamin C supplements as “treatments” for cancer. This year, US health chief Anthony Fauci and his South African counterpart Salim Abdool Karim were jointly awarded the main John Maddox prize for “communicating the complex science of Covid-19 in the midst of international uncertainty and anxiety”. However, the judges also gave an early career award to Abbott for her perseverance in challenging traditional surgical and stenting procedures as the main way to treat patients at risk of strokes. (A stent is a tiny tube that can be placed into an artery or vein.) © 2020 Guardian News & Media Limited

Keyword: Stroke
Link ID: 27634 - Posted: 12.22.2020

By Isabella Backman Even tough male chimps need their moms. Chimpanzees live in a male-dominated society, where most of their valuable allies are other males. However, as young male chimpanzees become adults, they continue to maintain tight bonds with their mothers, a new study reveals. And for about one-third of them, this mother-son relationship is the closest one they have. The dramatic changes of adolescence are difficult for chimps, just like they are for humans, says Elizabeth Lonsdorf, a primatologist at Franklin & Marshall College who was not involved in the study. And “sure enough,” she says, “their moms remain a key social partner during this turbulent time.” Previous research has shown chimpanzee mothers provide their sons support that goes far beyond nursing. Young male chimps that are close with their moms grow bigger and have a greater chance of survival. What’s more, losing their mothers after weaning, but before age 12, hinders the ability of young chimps to compete with other males and reproduce. To see whether this bond extends later into life, researchers followed 29 adolescent (9 to 15 years old) and young adult (16 to 20 years old) male chimpanzees at a research site in Kibale National Park in Uganda. For 3 years, they observed the chimps from a distance, recording any social interaction they witnessed. These included grooming, comforting behaviors such as holding hands or shoulder pats, looking back for or waiting for other individuals, offering support during conflicts, and sitting near each other. © 2020 American Association for the Advancement of Science.

Keyword: Evolution; Emotions
Link ID: 27633 - Posted: 12.22.2020

by Peter Hess Two types of neurons process social information, a new mouse study suggests, but only one is disrupted in mice missing the autism-linked gene FMR1. The neurons reside in a brain region called the hypothalamus, and both send signals via the hormone oxytocin. The deletion of FMR1, however, affects these cells differently: The loss of FMR1 in the smaller, ‘parvocellular’ neurons diminishes the mice’s interest in social interactions — but only those involving peers, the new work shows. The gene’s loss from the larger, ‘magnocellular’ neurons, by contrast, does not disrupt the animals’ interactions with either peers or parents. “There are a lot of different types of social behaviors, and not all of them are impaired in autism,” says lead investigator Gül Dölen, assistant professor of neuroscience at Johns Hopkins University in Baltimore, Maryland. Whereas peer-to-peer social interactions are troublesome for many autistic people, other social interactions — such as parental connections — are on par with those seen in non-autistic people, she says. This new understanding of the different neurons’ functions could help explain why clinical trials of oxytocin for treating autism traits have shown mixed results. It could also help scientists develop more effective treatments, experts say. “There are these two different kinds of neurons that we’ve known about for a really long time, and each of their contributions to social behavior has never really been dissected out,” says Larry Young, chief of behavioral neuroscience and psychiatric disorders at Emory University in Atlanta, Georgia, who was not involved with the study. “It’s really important for the future of drug development.” © 2020 Simons Foundation

Keyword: Autism; Hormones & Behavior
Link ID: 27632 - Posted: 12.19.2020

By Diana Kwon Seizures are like storms in the brain—sudden bursts of abnormal electrical activity that can cause disturbances in movement, behavior, feelings and awareness. For people with epilepsy, not knowing when their next seizure will hit can be psychologically debilitating. Clinicians have no way of telling people with epilepsy whether a seizure will likely happen five minutes from now, five weeks from now or five months from now, says Vikram Rao, a neurologist at the University of California, San Francisco. “That leaves people in a state of looming uncertainty.” Despite the apparent unpredictability of seizures, they may not actually be random events. Hints of cyclical patterns associated with epilepsy date back to ancient times, when people believed seizures were tied to the waxing and waning of the moon. While this particular link has yet to be definitively proven, scientists have pinpointed patterns in seizure-associated brain activity. Studies have shown that seizures are more likely during specific periods in the day, indicating an association with sleep–wake cycles, or circadian rhythms. In 2018, Rao and his colleagues reported the discovery of long-term seizure-associated brain rhythms—most commonly in the 20- to 30-day range—which they dubbed as “multidien” (multiday) rhythms. By examining these rhythms in brain activity, the group has now demonstrated that seizures can be forecast 24 hours in advance—and in some patients, up to three days prior. Their findings, published December 17 in Lancet Neurology, raise the possibility of eventually providing epilepsy patients with seizure forecasts that could predict the likelihood that a seizure will occur days in advance. © 2020 Scientific American,

Keyword: Epilepsy
Link ID: 27631 - Posted: 12.19.2020

Mercedes Burns An Asian water dragon hatched from an egg at the Smithsonian National Zoo, and her keepers were shocked. Why? Her mother had never been with a male water dragon. Through genetic testing, zoo scientists discovered the newly hatched female, born on Aug. 24, 2016, had been produced through a reproductive mode called parthenogenesis. Parthenogenesis is a Greek word meaning “virgin creation,” but specifically refers to female asexual reproduction. While many people may assume this behavior is the domain of science fiction or religious texts, parthenogenesis is surprisingly common throughout the tree of life and is found in a variety of organisms, including plants, insects, fish, reptiles and even birds. Because mammals, including human beings, require certain genes to come from sperm, mammals are incapable of parthenogenesis. Creating offspring without sperm Sexual reproduction involves a female and a male, each contributing genetic material in the form of eggs or sperm, to create a unique offspring. The vast majority of animal species reproduce sexually, but females of some species are able to produce eggs containing all the genetic material required for reproduction. Females of these species, which include some wasps, crustaceans and lizards, reproduce only through parthenogenesis and are called obligate parthenogens. A larger number of species experience spontaneous parthenogenesis, best documented in animals kept in zoo settings, like the Asian water dragon at the National Zoo or a blacktip shark at the Virginia Aquarium. Spontaneous parthenogens typically reproduce sexually, but may have occasional cycles that produce developmentally ready eggs. © 2010–2020, The Conversation US, Inc.

Keyword: Sexual Behavior
Link ID: 27630 - Posted: 12.19.2020