Jessica Koehler Ph.D. The only true voyage of discovery...would be not to visit strange lands, but to possess other eyes, to behold the universe through the eyes of another, of a hundred others, to behold the hundred universes that each of them beholds, that each of them is. Marcel Proust Perception is everything—and it is flawed. Most of us navigate our daily lives believing we see the world as it is. Our brains are perceiving an objective reality, right? Well, not quite. Everything we bring in through our senses is interpreted through the filter of our past experiences. Sensation is physical energy detection by our sensory organs. Our eyes, mouth, tongue, nose, and skin relay raw data via a process of transduction, which is akin to translation of physical energy—such as sound waves—into the electrochemical energy the brain understands. At this point, the information is the same from person to person—it is unbiased. To understand human perception, you must first understand that all information in and of itself is meaningless. Beau Lotto While Dr. Lotto's statement is bold, from the perspective of neuroscience, it is true. Meaning is applied to everything, from the simplest to the most complex sensory input. Our brain's interpretation of the raw sensory information is known as perception. Everything from our senses is filtered through our unique system of past experiences in the world. Usually, the meaning we apply is functional and adequate—if not fully accurate, but sometimes our inaccurate perceptions create real-world difficulty.

Keyword: Vision; Attention
Link ID: 27666 - Posted: 01.27.2021

by Peter Hess Mice missing a copy of the autism-linked gene MAGEL2 have trouble discerning between a familiar mouse and an unfamiliar one, but treating them with the social hormone vasopressin reverses this deficit, according to a new study. Mutations in or deletions of MAGEL2 are linked to autism and several related conditions, including Prader-Willi syndrome, which is characterized by intellectual disability, poor muscle tone, difficulty feeding and problems with social interactions. The new findings suggest that these social issues in people stem from impairments in vasopressin’s function in a brain region called the lateral septum, which relays signals between the hippocampus and the ventral tegmental area. They also hint that vasopressin treatment could remedy those issues, says Elizabeth Hammock, assistant professor of psychology and neuroscience at Florida State University in Tallahassee, who was not involved with the study. A 2020 study showed that low levels of vasopressin in cerebrospinal fluid can flag many infants who are later diagnosed with autism. But clinical trials have shown that either providing vasopressin or blocking its effects can improve social communication in autistic children. Because of these seemingly contradictory results, “a better understanding of how alterations in the vasopressinergic system leads to social deficits and how vasopressin administration could resolve some of these problems was needed,” says co-lead researcher Freddy Jeanneteau, professor of neuroscience at Montpellier University in Montpellier, France. © 2021 Simons Foundation

Keyword: Autism; Hormones & Behavior
Link ID: 27665 - Posted: 01.27.2021

By Clay Risen In 1978, James R. Flynn, a political philosopher at the University of Otago, in New Zealand, was writing a book about what constituted a “humane” society. He considered “inhumane” societies as well — dictatorships, apartheid states — and, in his reading, came across the work of Arthur R. Jensen, a psychologist at the University of California, Berkeley. Dr. Jensen was best known for an article he published in 1969 claiming that the differences between Black and white Americans on I.Q. tests resulted from genetic differences between the races — and that programs that tried to improve Black educational outcomes, like Head Start, were bound to fail. Dr. Flynn, a committed leftist who had once been a civil rights organizer in Kentucky, felt instinctively that Dr. Jensen was wrong, and he set out to prove it. In 1980 he published a thorough, devastating critique of Dr. Jensen’s work — showing, for example, that many groups of whites scored as low on I.Q. tests as Black Americans. But he didn’t stop there. Like most researchers in his field, Dr. Jensen had assumed that intelligence was constant across generations, pointing to the relative stability of I.Q. tests over time as evidence. But Dr. Flynn noticed something that no one else had: Those tests were recalibrated every decade or so. When he looked at the raw, uncalibrated data over nearly 100 years, he found that I.Q. scores had gone up, dramatically. “If you scored people 100 years ago against our norms, they would score a 70,” or borderline mentally disabled, he said later. “If you scored us against their norms, we would score 130” — borderline gifted. Just as groundbreaking was his explanation for why. The rise was too fast to be genetic, nor could it be that our recent ancestors were less intelligent than we are. Rather, he argued, the last century has seen a revolution in abstract thinking, what he called “scientific spectacles,” brought on by the demands of a technologically robust industrial society. This new order, he maintained, required greater educational attainment and an ability to think in terms of symbols, analogies and complex logic — exactly what many I.Q. tests measure. © 2021 The New York Times Company

Keyword: Learning & Memory; Development of the Brain
Link ID: 27664 - Posted: 01.27.2021

By Linda Searing A surge in the number of U.S. residents who have died of a drug overdose — 81,230 in the 12 months ending last May — set a record for the most such deaths in a one-year span, according to a report issued by the Centers for Disease Control and Prevention. Overall, drug overdose deaths jumped by 18 percent from the previous year, with increases recorded in 46 states (by more than 20 percent in 25 of those states) and just four states recording a decrease. Deaths attributed to synthetic opioids, mainly fentanyl, increased 38 percent nationwide, but 98 percent in 10 western states. Overdose deaths tied to cocaine use, often involving co-use or mixing with fentanyl or heroin, increased about 26 percent, and deaths linked to psychostimulants, such as methamphetamine, increased 35 percent. The CDC noted that the death rate from drug overdoses accelerated as the coronavirus pandemic set in, disrupting daily life and leading to isolation, depression, anxiety and economic distress for many, including people with a substance use disorder. In a health alert, the CDC urged broader distribution and use of naloxone, a medication that can block the effects of an overdose, as well as expanded prevention and treatment for those struggling with drug use. A free and confidential hotline, offering information and treatment referral, can be reached by calling the Substance Abuse and Mental Health Services Administration at 800-662-4357.

Keyword: Drug Abuse
Link ID: 27663 - Posted: 01.27.2021

By Katherine J. Wu For a lesson in euphoria, look no further than a house cat twined around a twig of silver vine. When offered a snipping of the plant, which contains chemicals similar to the ones found in catnip, most domesticated felines will purr, drool and smoosh their faces into its intoxicating leaves and stems, then zonk out in a state of catatonic bliss. But the ecstatic rush might not be the only reason felines flock to these plants, new research suggests. Compounds laced into plants like silver vine and catnip might also help cats ward off mosquitoes, equipping them with a DIY pest repellent that’s far more fun to apply than a greasy coat of DEET. Other papers have pointed to the insect-deterring effects of catnip and similar plants. But the new study, published Wednesday in the journal Science Advances, is the first to draw a direct link between the plants and their protective effects on cats. “It’s a really interesting observation, that such a well-known behavior could be having this unappreciated benefit for cats,” said Laura Duvall, a mosquito researcher at Columbia University in New York who wasn’t involved in the study. Botanically speaking, catnip and silver vine are distant cousins. But both contain iridoids, a suite of chemicals that seem to potently tickle pleasure circuits in cats. To pinpoint the evolutionary roots of this plant-feline connection, a team of researchers led by Masao Miyazaki, a biochemist and veterinary scientist at Iwate University in Japan, corralled a menagerie of cats — some domestic, some wild — and monitored their responses to an iridoid extracted from silver vine, which thrives in many mountainous parts of Asia. Presented with scraps of paper dosed with iridoid, most of the cats initiated a ritualized rolling and rubbing. Some cats were so eager to engage with the compounds that they climbed up the sides of their cages — some of which were nearly four feet tall — to anoint themselves with chemical-soaked paper secured to the ceiling. © 2021 The New York Times Company

Keyword: Drug Abuse
Link ID: 27662 - Posted: 01.23.2021

By Stephani Sutherland Patrick Thornton, a 40-year-old math teacher in Houston, Tex., relies on his voice to clearly communicate with his high school students. So when he began to feel he was recovering from COVID, he was relieved to get his voice back a month after losing it. Thornton got sick in mid-August and had symptoms typical of a moderate case: a sore throat, headaches, trouble breathing. By the end of September, “I was more or less counting myself as on the mend and healing,” Thornton says. “But on September 25, I took a nap, and then my mom called.” As the two spoke, Thornton’s mother remarked that it was great that his voice was returning. Something was wrong, however. “I realized that some of the words didn’t feel right in my mouth, you know?” he says. They felt jumbled, stuck inside. Thornton had suddenly developed a severe stutter for the first time in his life. “I got my voice back, but it broke my mouth,” he says. After relaying the story over several minutes, Thornton sighs heavily with exhaustion. The thought of going back to teaching with his stutter, “that was terrifying,” he says. In November Thornton still struggled with low energy, chest pain and headaches. And “sometimes my heart rate [would] just decide that we’re being chased by a tiger out of nowhere," he adds. His stutter only worsened by that time, Thornton says, and he worried that it reflected some more insidious condition in his brain, despite doctors’ insistence that the speech disruption was simply a product of stress. © 2021 Scientific American,

Keyword: Learning & Memory; Schizophrenia
Link ID: 27661 - Posted: 01.23.2021

by Angie Voyles Askham Mutations that affect a histone called H3.3 can lead to a neurodegenerative condition marked by developmental delay and congenital anomalies, according to a new study. Histones act as spools for DNA, making it possible to pack the strands of genetic material tightly within the nucleus. They also serve as gatekeepers for protein production, physically blocking proteins from interacting with genes, or allowing them access to turn genes on and off. Autism has been tied to mutations in proteins that modify histones and disrupt this gatekeeping process. The new work is among the first to link atypical neurodevelopment and degeneration to mutations that affect a histone itself. It focuses on 46 people with a mutation in either of two genes that code for H3.3. All have a diagnosis of developmental delay. Many also have other medical conditions, such as seizures, heart defects and atypical development of the head and face. “We see this [result] as a Rosetta Stone,” says lead researcher Elizabeth Bhoj, assistant professor of pediatrics and human genetics at the University of Pennsylvania. In addition to providing information about this particular cohort, the findings could help explain the role that histones play in neurodevelopmental conditions in general, she says. Earlier studies have associated H3.3 with cancer, but none of the participants in the new study have tumors. About 21 percent, however, show signs of neurodegeneration, and 26 percent have shrinkage in the cerebral cortex, the brain’s outer layer, suggesting the condition may be progressive. “It’s an impressive collection of novel mutations that seem to be converging on a set of clinical features,” says James Noonan, associate professor of genetics and neuroscience at Yale School of Medicine, who was not involved in the study. © 2021 Simons Foundation

Keyword: Autism; Epigenetics
Link ID: 27660 - Posted: 01.23.2021

By Mitch Leslie Spitting cobras protect themselves by shooting jets of venom into the eyes of their attackers. A new study suggests that over the course of several million years, all three groups of spitters independently tailored the chemistry of their toxins in the same way to cause pain to a would-be predator. The work provides a novel example of convergent evolution that “deepens our understanding of this unique system” for delivering venom, says Timothy Jackson, an evolutionary toxinologist at the University of Melbourne. Like other cobras, spitting cobras will bite attackers in self-defense. Spitting is their signature move, however, and the snakes are crack shots. They can direct a stream of venom into an attacker’s face from more than 2 meters away, aiming for the eyes. The behavior is such a formidable defense that it evolved independently three times: in Asian cobras, African cobras, and a cobra cousin called the rinkhals (Hemachatus haemachatus) that lives in southern Africa. Scientists previously found the venom of some other snakes evolved to better subdue their prey. By analyzing the venoms of 17 spitting and nonspitting species—and measuring their effects—venom biologist Nicholas Casewell of the Liverpool School of Tropical Medicine and colleagues tested whether the makeup of spitting cobra venom had also changed over time to become a more effective defense. © 2021 American Association for the Advancement of Science.

Keyword: Pain & Touch; Evolution
Link ID: 27659 - Posted: 01.23.2021

Bob McDonald Scientists used raw eggs to simulate the damaging effects on the brain from strikes to the head, with surprising results. If someone calls you an egghead, they are not too far off. Think about it: an egg has a hard outer shell; a liquid interior, which is the white of the egg; and liquid yolk surrounded by a membrane suspended in the centre. Your head also has a hard outer skull and liquid, called the cerebrospinal fluid, inside of it — which, among other things, acts as a shock absorber around the squishy brain. In a research paper in the journal Physics of Fluids, scientists from Villanova University in Pennsylvania conducted rather simple kitchen style experiments on raw eggs to simulate strikes to the head that could lead to concussion. They wanted to determine how much shock absorbing protection the egg white would provide the yolk and how much the yolk would be distorted out of shape during an impact. The results were not what they expected. Applying force to monitor yolk deformation In order to see the yolks in action, the egg material was placed in a clear plastic container that was mounted on springs and filmed with high speed cameras. First, they hit it in a straight line by dropping a 1.77 kg weight on it from a height of one metre. representing a direct blow to the head. To their surprise, the yolk remained suspended in the egg white and did not change shape or break as the container suddenly accelerated downwards. This could be because liquids cannot be compressed, and since the two liquids are almost the same density, both of them moved together as one unit. ©2021 CBC/Radio-Canada.

Keyword: Brain Injury/Concussion
Link ID: 27658 - Posted: 01.23.2021

By Diana Kwon Obsessive-compulsive disorder (OCD) is marked by repetitive, anxiety-inducing thoughts, urges and compulsions, such as excessive cleaning, counting and checking. These behaviors are also prevalent in the general population: one study in a large sample of U.S. adults found more than a quarter had experienced obsessions or compulsions at some point in their life. Although most of these individuals do not develop full-blown OCD, such symptoms can still interfere with daily life. A new study, published on January 18 in Nature Medicine, hints that these behaviors may be alleviated by stimulating the brain with an electrical current—without the need to insert electrodes under the skull. Robert Reinhart, a neuroscientist at Boston University, and his group drew on two parallel lines of research for this study. First, evidence suggests that obsessive-compulsive behaviors may arise as a result of overlearning habits—leading to their excessive repetition—and abnormalities in brain circuits involved in learning from rewards. Separately, studies point to the importance of high-frequency rhythms in the so-called high-beta/low-gamma range (also referred to as simply beta-gamma) in decision-making and learning from positive feedback. Drawing on these prior observations, Shrey Grover, a doctoral student in Reinhart’s lab, hypothesized with others in the team that manipulating beta-gamma rhythms in the orbitofrontal cortex (OFC)—a key region in the reward network located in the front of the brain—might disrupt the ability to repetitively pursue rewarding choices. In doing so, the researchers thought, the intervention could reduce obsessive-compulsive behaviors associated with maladaptive habits. To test this hypothesis, Grover and his colleagues carried out a two-part study. The first segment was aimed at identifying whether the high-frequency brain activity influenced how well people were able to learn from rewards. The team recruited 60 volunteers and first used electroencephalography to pinpoint the unique frequencies of beta-gamma rhythms in the OFC that were active in a given individual while that person took part in a task that involved associating symbols with monetary wins or losses. Previous work had shown that applying stimulation based on the particular patterns of rhythms in a person’s brain may enhance the effectiveness of the procedure. © 2021 Scientific American

Keyword: OCD - Obsessive Compulsive Disorder
Link ID: 27657 - Posted: 01.20.2021

Katherine J. Wu In a perfect world, the entrance to every office, restaurant and school would offer a coronavirus test — one with absolute accuracy, and able to instantly determine who was virus-free and safe to admit and who, positively infected, should be turned away. That reality does not exist. But as the nation struggles to regain a semblance of normal life amid the uncontrolled spread of the virus, some scientists think that a quick test consisting of little more than a stinky strip of paper might at least get us close. The test does not look for the virus itself, nor can it diagnose disease. Rather, it screens for one of Covid-19’s trademark signs: the loss of the sense of smell. Since last spring, many researchers have come to recognize the symptom, which is also known as anosmia, as one of the best indicators of an ongoing coronavirus infection, capable of identifying even people who don’t otherwise feel sick. A smell test cannot flag people who contract the coronavirus and never develop any symptoms at all. But in a study that has not yet been published in a scientific journal, a mathematical model showed that sniff-based tests, if administered sufficiently widely and frequently, might detect enough cases to substantially drive transmission down. Daniel Larremore, an epidemiologist at the University of Colorado, Boulder, and the study’s lead author, stressed that his team’s work was still purely theoretical. Although some smell tests are already in use in clinical and research settings, the products tend to be expensive and laborious to use and are not widely available. And in the context of the pandemic, there is not yet real-world data to support the effectiveness of smell tests as a frequent screen for the coronavirus. Given the many testing woes that have stymied pandemic control efforts so far, some experts have been doubtful that smell tests could be distributed widely enough, or made sufficiently cheat-proof, to reduce the spread of infection. © 2021 The New York Times Company

Keyword: Chemical Senses (Smell & Taste)
Link ID: 27656 - Posted: 01.20.2021

By Cathleen O’Grady Golden paper wasps have demanding social lives. To keep track of who’s who in a complex pecking order, they have to recognize and remember many individual faces. Now, an experiment suggests the brains of these wasps process faces all at once—similar to how human facial recognition works. It’s the first evidence of insects identifying one another using “holistic” processing, and a clue to why social animals have evolved such abilities. The finding suggests holistic processing might not require big, complex brains, says Rockefeller University neuroscientist Winrich Freiwald, who wasn’t involved with the research. “It must be so hard to train these animals, so I find it fascinating how one can get such clear results,” he says. Most people recognize faces not from specific features, such as a unique beauty spot or the shape of a nose, but by processing them as a whole, taking in how all the features hang together. Experiments find that people are good at discriminating between facial features—like noses—when they see them in the context of a face but find it much harder when the features are seen in isolation. Other primates, including chimpanzees and rhesus macaques, use such holistic processing. And studies have even found that honey bees and wasps, trained to recognize human faces, have more difficulty with partial faces than whole ones, suggesting holistic processing. But biologists didn’t know whether insects actually use holistic processing naturally with each other. © 2021 American Association for the Advancement of Science.

Keyword: Attention; Evolution
Link ID: 27655 - Posted: 01.20.2021

By Amy Barrett Amy Barrett: So, let’s start at the very beginning. What’s involved in forming a thought? David Badre: Forming a thought is sort of the core problem, that’s a big mystery in human psychology and neuroscience. This book is kind of asking the next question; how do we go from a thought that we have, that we form. Some idea about what we want to do, some task we want to take, some goal that we have. How do we translate that into the actions we need to do to actually achieve that? And that’s something that we kind of take for granted. We do it at lots of times during the course of our day. And these can be big goals. You know, you want to go to university or you want to start a business or something. But it can also be just simple everyday goals like going and getting a cup of coffee, which is the example I use in the book. All of that requires making a link between this idea you have, a goal you have, and the actual actions. It turns out that’s not a trivial thing. The brain requires a special class of mechanisms to do that. And those are called cognitive control mechanisms by scientists. And that’s really what the book is about, because it affects so many aspects of our lives. How we do that translation between our thoughts and how we behave. (C)BBC

Keyword: Attention
Link ID: 27654 - Posted: 01.20.2021

Researchers from the National Institutes of Health have discovered Jekyll and Hyde immune cells in the brain that ultimately help with brain repair but early after injury can lead to fatal swelling, suggesting that timing may be critical when administering treatment. These dual-purpose cells, which are called myelomonocytic cells and which are carried to the brain by the blood, are just one type of brain immune cell that NIH researchers tracked, watching in real-time as the brain repaired itself after injury. The study, published in Nature Neuroscience, was supported by the National Institute of Neurological Disorders and Stroke (NINDS) Intramural Research Program at NIH. “Fixing the brain after injury is a highly orchestrated, coordinated process, and giving a treatment at the wrong time could end up doing more harm than good,” said Dorian McGavern, Ph.D., NINDS scientist and senior author of the study. Cerebrovascular injury, or damage to brain blood vessels, can occur following several conditions including traumatic brain injury or stroke. Dr. McGavern, along with Larry Latour, M.D., NINDS scientist, and their colleagues, observed that a subset of stroke patients developed bleeding and swelling in the brain after surgical removal of the blood vessel clot responsible for the stroke. The swelling, also known as edema, results in poor outcomes and can even be fatal as brain structures become compressed and further damaged. To understand how vessel injury can lead to swelling and to identify potential treatment strategies, Dr. McGavern and his team developed an animal model of cerebrovascular injury and used state-of-the-art microscopic imaging to watch how the brain responded to the damage in real-time.

Keyword: Brain Injury/Concussion
Link ID: 27653 - Posted: 01.20.2021

Michelle Andrews Once the rules for implementing it are worked out, a bill signed into federal law in December will eliminate the required five-month waiting period for diagnosed ALS patients to begin disability benefits, enabling quicker Medicare coverage as well. LumiNola/Getty Images Anita Baron first noticed something was wrong in August 2018, when she began to drool. Her dentist chalked it up to a problem with her jaw. Then her speech became slurred. She managed to keep her company going — it offers financing to small businesses — but working became increasingly difficult for her as her speech worsened. Finally, nine months, four neurologists and countless tests later, Baron, now 66, got a diagnosis: amyotrophic lateral sclerosis. ALS, often called Lou Gehrig's disease after the New York Yankees first baseman who died of the disease in 1941, destroys motor neurons, causing people to lose control of their limbs, their speech and, ultimately, their ability to breathe. It's usually fatal in two to five years, though about 10% of people survive ten years or more. People with ALS often must quit their jobs — and sometimes their spouses do, too, to provide care — leaving families in financial distress. A decade-long campaign by advocates highlighting this predicament notched a victory last month when Congress passed a bill opening key support programs earlier for ALS patients. © 2021 npr

Keyword: ALS-Lou Gehrig's Disease
Link ID: 27652 - Posted: 01.20.2021

Daniel Osorio The neuroscientist Michael Land, who has died aged 78 from respiratory disease, was the Marco Polo of the visual sciences. He visited exotic parts of the animal kingdom, and showed that almost every way humans have discovered to bend, reflect, shape and image light with mirrors and lenses is also used by some creature’s eye. His research revealed the many different ways in which animals see their own versions of reality, often to find members of the opposite sex. His 1976 discovery that prawns focus light not by lenses, but with a structure of mirror-lined boxes, helped lead to the discovery of a method to focus X-rays, and in the 1990s he developed a simple device to track humans’ gaze as they move their eyes while doing everyday tasks. Land’s PhD thesis at University College London in the early 1960s, on how scallops evade the attacks of predatory starfish, turned out to be a serendipitous choice. He was supposed to investigate what passes for the brain of this shellfish, but found its eyes far more interesting. Scallops have many pinhead-sized eyes, just inside the lip of the shell. Rather than focusing light with a lens as people do, they use a concave mirror in the manner of a Newtonian telescope. Moving from UCL, with his first wife, Judith (nee Drinkwater), to the University of California, Berkeley, in 1968, he turned his attention to jumping spiders. These arachnids do not build webs but are visual hunters. Each of their four pairs of eyes has a different task, and Land showed how the most acute of these eyes moves to detect prey and mates. © 2021 Guardian News & Media Limited

Keyword: Vision; Evolution
Link ID: 27651 - Posted: 01.20.2021

Catherine S. Woolley, Ph.D. Sex differences in the brain are real, but they are not what you might think. They’re not about who is better at math, reading a map, or playing chess. They’re not about being sensitive or good at multi-tasking, either. Sex differences in the brain are about medicine and about making sure that the benefits of biomedical research are relevant for everyone, both men and women. You may be surprised to learn that most animal research is done in males. This is based on an erroneous view that hormonal cycles complicate studies in female research animals, and an assumption that the sexes are essentially the same down at cellular and molecular levels. But these beliefs are starting to change in neuroscience. New research shows that some fundamental molecular pathways in the brain operate differently in males and females, and not just by a little. In some cases, molecular sex differences are all-or-nothing. Recognition that male and female brains differ at a molecular level has the potential to transform biomedical research. Drugs act on molecular pathways. If those pathways differ between the sexes, we need to know how they differ as early as possible in the long (and expensive) process of developing new medicines and treatments for disease. The bulk of public attention to brain sex differences is focused on structural differences and their purported relationship to behavior or cognition. Yet structural sex differences are actually quite small, and their interpretation is often based on gender stereotypes with little to no scientific justification. © 2021 The Dana Foundation

Keyword: Sexual Behavior; Brain imaging
Link ID: 27650 - Posted: 01.15.2021

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