By Benjamin Ehrlich Hour after hour, year after year, Santiago Ramón y Cajal sat alone in his home laboratory, head bowed and back hunched, his black eyes staring down the barrel of a microscope, the sole object tethering him to the outside world. His wide forehead and aquiline nose gave him the look of a distinguished, almost regal, gentleman, although the crown of his head was as bald as a monk’s. He had only a crowd of glass bottles for an audience, some short and stout, some tall and thin, stopped with cork and filled with white powders and colored liquids; the other chairs, piled high with journals and textbooks, left no room for anyone else to sit. Stained with dye, ink and blood, the tablecloth was strewn with drawings of forms at once otherworldly and natural. Colorful transparent slides, mounted with slivers of nervous tissue from sacrificed animals still gummy to the touch from chemical treatments, lay scattered on the worktable. With his left thumb and forefinger, Cajal adjusted the corners of the slide as if it were a miniature picture frame under the lens of his microscope. With his right hand, he turned the brass knob on the side of the instrument, muttering to himself as he drew the image into focus: brownish-black bodies resembling inkblots and radiating threadlike appendages set against a transparent yellow background. The wondrous landscape of the brain was finally revealed to him, more real than he could have ever imagined. In the late 19th century most scientists believed the brain was composed of a continuous tangle of fibers as serpentine as a labyrinth. Cajal produced the first clear evidence that the brain is composed of individual cells, later termed neurons, that are fundamentally the same as those that make up the rest of the living world. He believed that neurons served as storage units for mental impressions such as thoughts and sensations, which combined to form our experience of being alive: “To know the brain is equivalent to ascertaining the material course of thought and will,” he wrote. The highest ideal for a biologist, he declared, is to clarify the enigma of the self. In the structure of neurons, Cajal thought he had found the home of consciousness itself. © 2022 Scientific American

Keyword: Brain imaging
Link ID: 28278 - Posted: 04.13.2022

Max Kozlov When neuroscientist Jakob Seidlitz took his 15-month-old son to the paediatrician for a check-up last week, he left feeling unsatisfied. There wasn’t anything wrong with his son — the youngster seemed to be developing at a typical pace, according to the height and weight charts the physician used. What Seidlitz felt was missing was an equivalent metric to gauge how his son’s brain was growing. “It is shocking how little biological information doctors have about this critical organ,” says Seidlitz, who is based at the University of Pennsylvania in Philadelphia. Soon, he might be able to change that. Working with colleagues, Seidlitz has amassed more than 120,000 brain scans — the largest collection of its kind — to create the first comprehensive growth charts for brain development. The charts show visually how human brains expand quickly early in life and then shrink slowly with age. The sheer magnitude of the study, published in Nature on 6 April1, has stunned neuroscientists, who have long had to contend with reproducibility issues in their research, in part because of small sample sizes. Magnetic resonance imaging (MRI) is expensive, meaning that scientists are often limited in the number of participants they can enrol in experiments. “The massive data set they assembled is extremely impressive and really sets a new standard for the field,” says Angela Laird, a cognitive neuroscientist at Florida International University in Miami. Even so, the authors caution that their database isn’t completely inclusive — they struggled to gather brain scans from all regions of the globe. The resulting charts, they say, are therefore just a first draft, and further tweaks would be needed to deploy them in clinical settings. If the charts are eventually rolled out to paediatricians, great care will be needed to ensure that they are not misinterpreted, says Hannah Tully, a paediatric neurologist at the University of Washington in Seattle. “A big brain is not necessarily a well-functioning brain,” she says. © 2022 Springer Nature Limited

Keyword: Development of the Brain; Brain imaging
Link ID: 28277 - Posted: 04.09.2022

By Alla Katsnelson A dog gives a protective bark, sensing a nearby stranger. A cat slinks by disdainfully, ignoring anyone and everyone. A cow moos in contentment, chewing its cud. At least, that’s what we may think animals feel when they act the way they do. We take our own lived experiences and fill in gaps with our imaginations to better understand and relate to the animals we encounter. Often, our assumptions are wrong. Take horse play, for example. Many people assume that these muscular, majestic animals are roughhousing just for the fun of it. But in the wild, adult horses rarely play. When we see them play in captivity, it isn’t necessarily a good sign, says Martine Hausberger, an animal scientist at CNRS at the University of Rennes in France. Hausberger, who raises horses on her farm in Brittany, began studying horse welfare about three decades ago, after observing that people who keep horses often misjudge cues about the animals’ behavior. Adult horses that play are often ones that have been restrained, Hausberger says. Play seems to discharge the stress from that restriction. “When they have the opportunity, they may exhibit play, and at that precise moment they may be happier,” she says. But “animals that are feeling well all the time don’t need this to get rid of the stress.” Scientists studying animal behavior and animal welfare are making important strides in understanding how the creatures we share our planet with experience the world. “In the last decade or two, people have gotten bolder and more creative in terms of asking what animals’ emotional states are,” explains Georgia Mason, a behavioral biologist and animal welfare scientist at the University of Guelph in Canada. They’re finding thought-provoking answers amid a wide array of animals. © Society for Science & the Public 2000–2022.

Keyword: Emotions; Evolution
Link ID: 28276 - Posted: 04.09.2022

By Paula Span On a recent afternoon in Bastrop, Texas, Janet Splawn was walking her dog, Petunia, a Pomeranian-Chihuahua mix. She said something to her grandson, who lives with her and had accompanied her on the stroll. But he couldn’t follow; her speech had suddenly become incoherent. “It was garbled, like mush,” Ms. Splawn recalled a few days later from a hospital in Austin. “But I got mad at him for not understanding. It was kind of an eerie feeling.” People don’t take chances when 87-year-olds develop alarming symptoms. Her grandson drove her to the nearest hospital emergency room, which then transferred her to a larger hospital for a neurology consultation. The diagnosis: a transient ischemic attack, or T.I.A. For decades, patients have been relieved to hear that phrase. The sudden onset of symptoms like weakness or numbness (often on one side), loss of vision (often in one eye) and trouble with language (speaking, understanding or both) — if resolved in a few minutes — is considered “transient.” Whew. But in a recent editorial in JAMA, two neurologists called for doctors and patients to abandon the term transient ischemic attack. It’s too reassuring, they argued, and too likely to lead someone with passing symptoms to wait until the next morning to call a doctor or let a week go by before arranging an appointment. That’s dangerous. Better, they said, to call a T.I.A. what it is: a stroke. More specifically, a minor ischemic stroke. (Almost 90 percent of strokes, which afflict 795,000 Americans a year, are ischemic, meaning they result from a clot that reduces blood flow to the brain.) Until recently, T.I.A.s “were played down,” said Dr. J. Donald Easton, a neurologist recently retired from the University of California, San Francisco, and an author of the editorial. “The person thinks, ‘Oh, it’s over. It goes away, so all is well.’ But all is not well. There’s trouble to come, and it’s coming soon.” The advent of brain imaging — first CT scans in the late 1970s, then the more precise M.R.I.s in the 1990s — has shown that many T.I.A.s, sometimes called ministrokes, cause visible and permanent brain damage. © 2022 The New York Times Company

Keyword: Stroke
Link ID: 28275 - Posted: 04.09.2022

By Lenny Bernstein Researchers have found variations in a small number of genes that appear to dramatically increase the likelihood of developing schizophrenia in some people. The interplay of a wide array of other genes is implicated for most people with schizophrenia, a severe brain disorder characterized by hallucinations, delusions and inability to function. But for some who possess mutations in the 10 genes identified in the new study, published Wednesday in the journal Nature, the likelihood of developing the disease can be 10, 20 and even 50 times greater. The discovery could one day lead to advances in diagnosis of, and therapy for, the disease, according to the lead author of the study, Tarjinder Singh, of the Broad Institute at MIT and Harvard, which led an effort that involved years of work by dozens of research institutions worldwide. “This is the biological clue that leads to better therapies,” Singh said in an interview. “But the key thing is, we haven’t had any meaningful clues for the longest time.” Ken Duckworth, chief medical officer for the National Alliance on Mental Illness, a nationwide advocacy group, said the study is an important development in the neuroscience that underlies schizophrenia. But he said it is difficult to predict how soon such basic research would pay off for people living with the disease. “This is a big step forward for science that may pay a long-term return for people with schizophrenia and the people who live with them,” Duckworth said. But, he said, “if this is a 17-inning game and they’ve gotten us from the first to the second inning, how does this help someone today?” Less than 1 percent of the U.S. population is believed to have schizophrenia, which is generally treated with an array of powerful antipsychotic medications. The disease reduces life expectancy by about 15 years, according to the new research. Scientists have long recognized a hereditary component to the disease, along with other factors such as environment. The work of isolating these genes could not have been accomplished even 10 or 15 years ago, Singh said, before the sequencing of the human genome and the spread of technology that allows such genetic detective work to be conducted in laboratories around the world. © 1996-2022 The Washington Post

Keyword: Schizophrenia; Genes & Behavior
Link ID: 28274 - Posted: 04.09.2022

By Richard Sandomir Terry Wallis, who spontaneously regained his ability to speak after a traumatic brain injury left him virtually unresponsive for 19 years, and who then became a subject of a major study that showed how a damaged brain could heal itself, died on March 29 in a rehabilitation facility in Searcy, Ark. He was 57. He had pneumonia and heart problems, said his brother George Wallis, who confirmed the death. Terry Wallis was 19 when the pickup truck he was in with two friends skidded off a small bridge in the Ozark Mountains of northern Arkansas and landed upside down in a dry riverbed. The accident left him in a coma for a brief time, then in a persistent vegetative state for several months. One friend died; the other recovered. Until 2003, Mr. Wallis lay in a nursing home in a minimally conscious state, able to track objects with his eyes or blink on command. But on June 11, 2003, he effectively returned to the world when, upon seeing his mother, Angilee, he suddenly said, “Mom.” At the sight of the woman he was told was his adult daughter, Amber, who was six weeks old at the time of the accident, he said, “You’re beautiful,” and told her that he loved her. “Within a three-day period, from saying ‘Mom’ and ‘Pepsi,’ he had regained verbal fluency,” said Dr. Nicholas Schiff, a professor of neurology and neuroscience at Weill Cornell Medicine in Manhattan who led imaging studies of Mr. Wallis’s brain. The findings were presented in 2006 in The Journal of Clinical Investigation. “He was disoriented,” Dr. Schiff, in a phone interview, said of Mr. Wallis’s emergence. “He thought it was still 1984, but otherwise he knew all the people in his family and had that fluency.” Mr. Wallis’s brain scans — the first ever of a late-recovering patient — revealed changes in the strength of apparent connections within the back of the brain, which is believed to have helped his conscious awareness, and in the midline cerebellum, an area involved in motor control, which may have accounted for the very limited movement in his arms and legs while he was minimally conscious. © 2022 The New York Times Company

Keyword: Consciousness
Link ID: 28273 - Posted: 04.09.2022

Yasemin Saplakoglu A mosquito watches you through a lattice of microscopic lenses. You stare back, fly swatter in hand, closely tracking the bloodsucker with your humble single-lens eyes. But it turns out that the way you see each other — and the world — may have more in common than you might think. A study published last month in Science Advances found that inside mammalian eyes, mitochondria, the organelles that power cells, may serve a second role as microscopic lenses, helping to focus light on the photoreceptor pigments that convert the light into neural signals for the brain to interpret. The findings, which draw a striking parallel between mammalian eyes and the compound eyes of insects and other arthropods, suggest that our own eyes have hidden levels of optical complexity, and that evolution has found new uses for very old parts of our cellular anatomy. Abstractions navigates promising ideas in science and mathematics. Journey with us and join the conversation. The lens at the very front of the eye focuses light from the environment onto a thin layer of tissue called the retina in the back. There, photoreceptor cells — cones that paint our world in color and rods that help us navigate in low light — absorb the light and translate it into nerve signals that propagate into the brain. But light-sensitive pigments sit at the very ends of photoreceptors, right behind a thick bundle of mitochondria. The odd placement of this bundle turns the mitochondria into seemingly unnecessary, light-scattering obstacles. The mitochondria are the “final hurdle” for the light particles, said Wei Li, a senior investigator at the National Eye Institute and senior author on the paper. For years, vision scientists couldn’t make sense of this odd placement of these organelles — after all, most cells have their mitochondria hugging their center organelle, the nucleus. All Rights Reserved © 2022

Keyword: Vision
Link ID: 28272 - Posted: 04.06.2022

By Ingrid K. Williams This article is part of a limited series on artificial intelligence’s potential to solve everyday problems. Imagine a test as quick and easy as having your temperature taken or your blood pressure measured that could reliably identify an anxiety disorder or predict an impending depressive relapse. Health care providers have many tools to gauge a patient’s physical condition, yet no reliable biomarkers — objective indicators of medical states observed from outside the patient — for assessing mental health. But some artificial intelligence researchers now believe that the sound of your voice might be the key to understanding your mental state — and A.I. is perfectly suited to detect such changes, which are difficult, if not impossible, to perceive otherwise. The result is a set of apps and online tools designed to track your mental status, as well as programs that deliver real-time mental health assessments to telehealth and call-center providers. Psychologists have long known that certain mental health issues can be detected by listening not only to what a person says but how they say it, said Maria Espinola, a psychologist and assistant professor at the University of Cincinnati College of Medicine. With depressed patients, Dr. Espinola said, “their speech is generally more monotone, flatter and softer. They also have a reduced pitch range and lower volume. They take more pauses. They stop more often.” Patients with anxiety feel more tension in their bodies, which can also change the way their voice sounds, she said. “They tend to speak faster. They have more difficulty breathing.” Today, these types of vocal features are being leveraged by machine learning researchers to predict depression and anxiety, as well as other mental illnesses like schizophrenia and post-traumatic stress disorder. The use of deep-learning algorithms can uncover additional patterns and characteristics, as captured in short voice recordings, that might not be evident even to trained experts. © 2022 The New York Times Company

Keyword: Depression; Schizophrenia
Link ID: 28271 - Posted: 04.06.2022

ByTess Joosse My dog Leo clearly knows the difference between my voice and the barks of the beagle next door. When I speak, he looks at me with love; when our canine neighbor makes his mind known, Leo barks back with disdain. A new study backs up what I and my fellow dog owners have long suspected: Dogs’ brains process human and canine vocalizations differently, suggesting they evolved to recognize our voices from their own. “The fact that dogs use auditory information alone to distinguish between human and dog sound is significant,” says Jeffrey Katz, a cognitive neuroscientist at Auburn University who is not involved with the work. Previous research has found that dogs can match human voices with expressions. When played an audio clip of a lady laughing, for example, they’ll often look at a photo of a smiling woman. But how exactly the canine brain processes sounds isn’t clear. MRI has shown certain regions of the dog brain are more active when a pup hears another dog whine or bark. But those images can’t reveal exactly when neurons in the brain are firing, and whether they fire differently in response to different noises. So in the new study, Anna Bálint, a canine neuroscientist at Eötvös Loránd University, turned to an electroencephalogram, which can measure individual brain waves. She and her colleagues recruited 17 family dogs, including several border collies, golden retrievers, and a German shepherd, that were previously taught to lie still for several minutes at a time. The scientists attached electrodes to each dog’s head to record its brain response—not an easy task, it turns out. Unlike humans’ bony noggins, dog heads have lots of muscles that can obstruct a clear readout, Bálint says. © 2022 American Association for the Advancement of Science.

Keyword: Language; Animal Communication
Link ID: 28270 - Posted: 04.06.2022

By Jessica Contrera The carpet cleaner heaves his machine up the stairs, untangles its hoses and promises to dump the dirty water only in the approved toilet. Another day scrubbing rugs for less than $20 an hour. Another Washington area house with overflowing bookshelves and walls covered in travel mementos from places he would love to go one day. But this was not that day. “Tell me about this stain,” 46-year-old Vaughn Smith asks his clients. “Well,” says one of the homeowners, “Schroeder rubbed his bottom across it.” Vaughn knows just what to do about that, and the couple, Courtney Stamm and Kelly Widelska, know they can trust him to do it. They’d been hiring him for years, once watching him erase even a splattered Pepto Bismol stain. But this time when Vaughn called to confirm their January appointment, he quietly explained that there was something about himself that he’d never told them. That he rarely told anyone. And well, a reporter was writing a story about it. Could he please bring her along? Now as they listen to Vaughn discuss the porousness of wool, and the difference between Scotchgard and sanitizer, they can’t help but look at him differently. Once the stool stain is solved, Kelly just has to ask. “So, how many languages do you speak?” “Oh goodness,” Vaughn says. “Eight, fluently.” “Eight?” Kelly marvels. “Eight,” Vaughn confirms. English, Spanish, Bulgarian, Czech, Portuguese, Romanian, Russian and Slovak. “But if you go by like, different grades of how much conversation,” he explains, “I know about 25 more.” Vaughn glances at me. He is still underselling his abilities. By his count, it is actually 37 more languages, with at least 24 he speaks well enough to carry on lengthy conversations. He can read and write in eight alphabets and scripts. He can tell stories in Italian and Finnish and American Sign Language. He’s teaching himself Indigenous languages, from Mexico’s Nahuatl © 1996-2022 The Washington Post

Keyword: Language; Autism
Link ID: 28269 - Posted: 04.06.2022

Dustin Jones Researchers from Sweden and the United Kingdom teamed up to sniff out the answer to a question practically every person has pondered at one time or another: what is the best smell out there? They found that most people, despite coming from different cultures and backgrounds, find vanilla to be the most pleasant smell on the planet more often than not. Sour, stinky feet? Not so much. The collaborative study between Sweden's Karolinska Institutet and the University of Oxford found that people share similar preferences when it comes to smell, regardless of cultural background. And according to the results, vanilla is the most pleasing smell around, followed by ethyl butyrate, which smells like peaches. Artin Arshamian, researcher at Karolinska and one of the study's authors, said humans may have similar olfactory preferences because it helped early humans survive. Which may very well explain why stinky feet came in dead last as far as appealing odors are concerned. According to the study, the pleasantness of a smell can be attributed to the structure of an edible item's odor molecule 41% of the time. Simply put, humans likely enjoy many of the same smells, more often than not, because of a deep-rooted sense that an item is safe to eat. Sponsor Message "We wanted to examine if people around the world have the same smell perception and like the same types of [odor], or whether this is something that is culturally learned," Arshamian said. "Traditionally it has been seen as cultural, but we can show that culture has very little to do with it." © 2022 npr

Keyword: Chemical Senses (Smell & Taste)
Link ID: 28268 - Posted: 04.06.2022

Hannah Devlin Science correspondent The largest genetic study of Alzheimer’s to date has provided compelling evidence linking the disease to disruption in the brain’s immune system. The study, using the genomes of 100,000 people with Alzheimer’s and 600,000 healthy people, identified 75 genes linked to an increased risk of the disease, including 42 that had not previously been implicated. The findings suggest degeneration in the brains of dementia patients could be spurred on by “over-aggressive” activity in the brain’s immune cells, called microglia. Prof Julie Williams, the director of the UK Dementia Research Institute at Cardiff University and a co-author of the study, said the findings could help reignite efforts to find an effective treatment. “This is an enormous clue to what’s going wrong,” she said. “Eight or nine years ago we weren’t working on the immune system. The genetics has refocused us.” The study, the largest of its kind to date, also allowed scientists to devise a genetic risk score that could predict which patients with cognitive impairment would, within three years of first showing symptoms, go on to develop Alzheimer’s. The score is not intended for clinical use at the moment, but could be used when recruiting people for clinical trials of drugs aimed at treating the disease in the earliest stages. Alzheimer’s disease is the most common cause of dementia, which affects more than 850,000 people in the UK. Despite the huge burden of the disease, there have been no new drugs for it in the past two decades, with the exception of Aducanumab, controversially licensed in the US but unavailable in Europe and the UK. Previous research has shown that while lifestyle factors such as smoking, exercise and diet influence Alzheimer’s risk, 60%-80% of the disease risk is based on genetics. However, Williams said, drug development was heavily influenced by the study of families with rare genetic mutations causing early onset Alzheimer’s. © 2022 Guardian News & Media Limited

Keyword: Alzheimers; Genes & Behavior
Link ID: 28267 - Posted: 04.06.2022

By Carolyn Gramling Modern mammals are known for their big brains. But new analyses of mammal skulls from creatures that lived shortly after the dinosaur mass extinction shows that those brains weren’t always a foregone conclusion. For at least 10 million years after the dinosaurs disappeared, mammals got a lot brawnier but not brainier, researchers report in the April 1 Science. That bucks conventional wisdom, to put it mildly. “I thought, it’s not possible, there must be something that I did wrong,” says Ornella Bertrand, a mammal paleontologist at the University of Edinburgh. “It really threw me off. How am I going to explain that they were not smart?” Modern mammals have the largest brains in the animal kingdom relative to their body size. How and when that brain evolution happened is a mystery. One idea has been that the disappearance of all nonbird dinosaurs following an asteroid impact at the end of the Mesozoic Era 66 million years ago left a vacuum for mammals to fill (SN: 1/25/17). Recent discoveries of fossils dating to the Paleocene — the immediately post-extinction epoch spanning 66 million to 56 million years ago — does reveal a flourishing menagerie of weird and wonderful mammal species, many much bigger than their Mesozoic predecessors. It was the dawn of the Age of Mammals. Before those fossil finds, the prevailing wisdom was that in the wake of the mass dino extinction, mammals’ brains most likely grew apace with their bodies, everything increasing together like an expanding balloon, Bertrand says. But those discoveries of Paleocene fossil troves in Colorado and New Mexico, as well as reexaminations of fossils previously found in France, are now unraveling that story, by offering scientists the chance to actually measure the size of mammals’ brains over time. © Society for Science & the Public 2000–2022.

Keyword: Evolution
Link ID: 28266 - Posted: 04.02.2022

ByKelly Servick An experimental pain drug that may offer an alternative to opioids has shown promise in two small clinical trials for acute pain, its developer announced today. Vertex Pharmaceuticals’s compound, called VX-548, outperformed a placebo in phase 2 trials for two types of postsurgical pain, the company said in a press release. The results pave the way for larger trials that could lead to regulatory approval. “This is a major advance in the effort to supersede opioids,” says John Wood, a neurobiologist at University College London who has studied the cellular channel that VX-548 targets. “These results are terrific, and the side effect profile is very good.” Opioids are powerful pain relievers, but they can cause side effects including slowed breathing, and they come with the potential for addiction. An epidemic of overdose deaths has prompted a hunt for safer alternatives. The new trials grew out of research into sodium channels on the surface of pain-sensing neurons, which let them fire electrical signals. One such channel, called Nav1.8, is crucial to relaying pain signals to the spinal cord from nerves throughout the body. People with genetic mutations that make Nav1.8 hyperactive can suffer pain even in the absence of injury. But relieving pain by blocking either Nav1.8 or another channel, Nav1.7, has proved difficult. One issue is their structure closely resembles those of other sodium channels, which regulate vital functions in the heart, muscles, and brain. To be safe, a compound needs to target the channel of interest and not accidentally target these other, critical channels. Vertex has spent years developing highly specific Nav1.8-blocking drugs, but it has abandoned previous candidates before they reached pivotal phase 3 trials. One drug, known as VX-150, succeeded in three phase 2 clinical studies but never advanced to larger ones, in part because its high dose might be impractical for clinical use. “We wanted to have higher potency,” explains Vertex Chief Scientific Officer David Altshuler. © 2022 American Association for the Advancement of Science.

Keyword: Pain & Touch
Link ID: 28265 - Posted: 04.02.2022

Jonathan Franklin Legendary actor Bruce Willis announced Wednesday his departure from the big screen following his diagnosis with aphasia, which is "impacting his cognitive abilities," his family said in a statement. While details of what led to Willis' aphasia diagnosis are unknown at this time, medical experts stress the importance of the brain condition and how its specifically treated — depending on its severity. "[At some point], people will know somebody who's had a stroke and has aphasia," Dr. Swathi Kiran, professor of neurorehabilitation at Boston University, told NPR. Bruce Willis stepping away from acting for health reasons, his family says Aphasia is defined as a condition that affects the ability to speak, write and understand language, according to the Mayo Clinic. The brain disorder can occur after strokes or head injuries — and can even lead in some cases to dementia. "As a result of this and with much consideration Bruce is stepping away from the career that has meant so much to him," his daughter, Rumer Willis, said on Instagram. "This is a really challenging time for our family and we are so appreciative of your continued love, compassion and support." Medical experts say the impacts of aphasia can vary, depending on the person's diagnosis. But mainly, the condition affects a person's ability to communicate — whether it's written, spoken or both. People living with aphasia can experience changes in their ability to communicate; as they may find difficulty finding words, using words out of order or will even speak in a short manner, according to the American Speech-Language-Hearing Association. © 2022 npr

Keyword: Language; Stroke
Link ID: 28264 - Posted: 04.02.2022

By Lisa Sanders, M.D. The 51-year-old man sat at his desk preparing for his next online meeting when he suddenly became aware of a familiar stiffness and exhaustion. Had he slept badly? Or was this the beginning of one of his strange episodes? As the symptoms worsened, he had his answer. He knew that when he started to feel this way, the only recourse was to get into bed before he got any weaker. As he made his way slowly down the hall, his legs felt heavy, as if he were wearing ankle weights. Just lifting them was real work. He passed his wife’s home office without a word. She knew just from looking at him that he would probably have to spend the rest of the day in bed. For much of their 30-year marriage, he had these strange spells; he would suddenly feel exhausted and weak and have to lie down. He couldn’t work. He was a software engineer, and any mental exertion was too much for him. Once the fatigue fully set in — maybe after the first hour or so — he couldn’t walk, couldn’t stand, couldn’t even sit up. It was as if his body was totally out of gas, worse than how it felt when he ran a marathon. He would lie in a dark room, too weak to even hold up a book and too tired to think. But by the next morning, he would usually be fine, brimming with energy and enthusiasm, like normal. It was so strange. After more than 20 years, they both had come to expect these episodes. For most of that time, the spells were infrequent, maybe once a month. But recently they became more frequent. The monthly episodes became weekly, then a couple of times a week. They often came, as they did that morning, out of nowhere. Just before leaving his office, he sent an email to the woman he was to meet online. Sorry, he wrote, I’m not feeling well. Could we reschedule? Seeing a Psychiatrist Over the years the man saw many doctors. They had their theories, but so far none panned out. A few were convinced that he had periodic paralysis, a disorder sometimes linked to thyroid disease, where patients become temporarily paralyzed by too much or too little potassium in the bloodstream. But his potassium was always normal, even during these episodes. © 2022 The New York Times Company

Keyword: Pain & Touch
Link ID: 28263 - Posted: 04.02.2022

Dolphins are known to use physical contact like petting and rubbing to bond with their closest allies. But for more distant contacts, male dolphins bond by trading whistles instead. KELSEY SNELL, HOST: You know those friends who live far away, but you still stay in touch? You can't really hug, so you call or text them instead. Well, dolphins do something sort of similar. AILSA CHANG, HOST: That, my friends, is whistling. A new study found that the male bottlenose dolphins in Western Australia whistle to the other male dolphins they don't have strong bonds with. SNELL: University of Bristol marine biologist Emma Chereskin is the lead author of the study. She explains that male bottlenose dolphins have an alliance structure. They have their closest circle where the bonds are strong. EMMA CHERESKIN: They often use physical touch, so rubbing their fins together, swimming side by side. CHANG: Then there is another circle where the bonds are weaker and they don't use as much physical touch, but they do whistle to identify themselves and to keep alliances intact. In other words, they bond at a distance. Sound familiar? SNELL: That was a whistle exchange between three dolphins. The researchers gave them names - Kooks (ph), Spirit and Guppy. CHERESKIN: They're saying, hi, I'm Kooks. I'm right here. And then Spirit would reply, hi, I'm Spirit. I'm also right here. And then Guppy gets in on it towards the end. He's saying, hi, I'm Guppy. I'm also here. CHANG: The study tests the social bonding hypothesis of Robin Dunbar. He proposed that animal vocalizations evolved as a form of vocal grooming to replace physical grooming. Karl Berg from the University of Texas Rio Grande Valley says this study advances that hypothesis. KARL BERG: These dolphin groups can be in really large groups in the dark ocean where visual communication isn't going to be possible. It makes sense that this vocal communication system is very important to them. © 2022 npr

Keyword: Animal Communication; Evolution
Link ID: 28262 - Posted: 04.02.2022

Elena Renken Even when it’s not apparent, cells in our tissues and organs are constantly on the move. In fact, the ability of cells to get where they need to go is essential to our health and survival. Skin cells migrate to heal wounds. Immune system cells migrate to fight infections. “Every day, you look at your body and it’s not changing much,” said Peter Devreotes, a professor of cell biology at the Johns Hopkins University School of Medicine. “But the cells within it are migrating constantly.” It starts from the earliest stages of life. When we are embryos just a few weeks old, a special population of “neural crest” cells in our back suddenly spreads through the body to become a wide range of essential tissues — bones, cartilage and nerves in the face, tendons, pigment cells in the skin, parts of the heart and more. But how do these cells know where to go? Studies long suggested that they were following chemical trails to their routes. Biologists traditionally saw these chemical gradients as simple and the cells as mere followers: Like dogs trotting toward the scent of food, the cells sensed the gradient and followed the stream of signals back to the source. Countless examples of this have been found among bacteria and other cells navigating through the wild, as well as inside larger organisms. When you nick your skin, for instance, the tissue around the cut releases a cloud of molecules that attract immune cells nearby. The immune cells crawl toward it and stave off infection. Yet scientists also came to understand that this system can’t sustain many of the migrations that unfold in the body. The structure of simple passive gradients is too fragile and too easily disrupted. Simple gradients like these don’t always reach far enough to guide cells’ lengthier journeys, and they may dissipate too quickly to maintain migrations that take longer. Raising the sensitivity of the cells might seem like a way to offset those problems, but then cells might often be too flooded with signals to sense where they come from. For a simple gradient to work, it has to be perfect, and nothing can go awry. But in reality, cells must find a way to navigate under all kinds of conditions. All Rights Reserved © 2022

Keyword: Development of the Brain
Link ID: 28261 - Posted: 03.30.2022

By Gina Kolata Last week, two patients asked Dr. Stanley L. Hazen, a cardiologist at the Cleveland Clinic, how much daily alcohol consumption would be good for their cardiac health. He gave them both well-accepted medical advice — an average of about one drink a day helps the heart. “I didn’t give it a second thought,” he said. Then he saw a paper published in JAMA Network Open whose findings upended his thinking about what to tell patients. The paper, he said, “totally changes my life.” Its conclusion: There is no level of drinking that does not confer heart disease risk. The risk is small if people have an average of seven drinks a week when compared with none. But it increases quickly as the level of alcohol consumption rises. “Dose matters a lot,” said Dr. Krishna G. Aragam, a preventive cardiologist at Massachusetts General Hospital and an author of the study. “Just realize that, as you go up beyond modest ranges, the risk goes up quite a bit.” The study, which may help resolve medical disputes over the effects of alcohol on the heart, involved sophisticated analyses of the genes and medical data of nearly 400,000 people who participate in the U.K. Biobank, a British repository that investigators use to study genes and their relation to health. The average age of subjects selected for the alcohol study was 57, and they reported consuming an average of 9.2 drinks a week. Some researchers have reported that drinking modestly protects the heart because moderate drinkers as a group have less heart disease than those who drink heavily or those who abstain. Dr. Aragam and his colleagues also saw that effect. But the reason, they report, is not that alcohol protects the heart. It is that light to moderate drinkers — those who consume up to 14 drinks a week — tend to have other characteristics that decrease their risk, like smoking less, exercising more and weighing less than those who drink more heavily and those who do not drink. © 2022 The New York Times Company

Keyword: Drug Abuse
Link ID: 28260 - Posted: 03.30.2022

By Ariana Eunjung Cha People with “chemo brain” and covid brain fog could not seem more different: Those with “chemo brain” have a life-threatening disease for which they’ve taken toxic drugs or radiation. Many of those with covid brain fog, in contrast, describe themselves as previously healthy people who have had a relatively mild infection that felt like a cold. So when Stanford University neuroscientist Michelle Monje began studies on long covid, she was fascinated to find similar changes among patients in both groups, in specialized brain cells that serve as the organ’s surveillance and defense system. “It was really quite striking,” Monje said. In cancer patients undergoing treatment, a malfunction in those same cells, known as microglia, are believed to be a cause of the fuzzy thinking that many describe. Scientists have also theorized that in Alzheimer’s disease, these cells may be impeded, making it difficult for them to counteract the cellular wear and tear of aging. Monje’s project is part of a crucial and growing body of research that suggests similarities in the mechanisms of post-covid cognitive changes and other long-studied brain conditions, including “chemo brain,” Alzheimer’s and other post-viral syndromes following infections with influenza, Epstein-Barr, HIV or Ebola. “There is humongous overlap” between long covid and these other conditions, said Avindra Nath, intramural clinical director of the neurological disorders and stroke unit of the National Institutes of Health. Pre-covid, much of the medical research into brains (as well as other organs) was siloed by disease. But during the pandemic, as diverse scientists banded together to understand a complex, multi-organ disease, commonalities among the conditions began coming to light. © 1996-2022 The Washington Post

Keyword: Alzheimers; Learning & Memory
Link ID: 28259 - Posted: 03.30.2022