Chapter 15. Emotions, Aggression, and Stress

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By Lisa Sanders, M.D. The voice on the phone was kind but firm: “You need to go to the emergency room. Now.” Her morning was going to be busy, replied the 68-year-old woman, and she didn’t feel well. Could she go later today or maybe tomorrow? No, said Dr. Benison Keung, her neurologist. She needed to go now; it was important. As she hung up the phone, tears blurred the woman’s already bad vision. She’d been worried for a while; now she was terrified. She was always healthy, until about four months earlier. It was a Saturday morning when she noticed that something seemed wrong with her right eye. She hurried to the bathroom mirror, where she saw that her right eyelid was drooping, covering the top half of the brown of her iris. On Monday morning, when she met her eye doctor, she was seeing double. Since then she’d had tests — so many tests — but received no answers. The woman walked to the bedroom where her 17-year-old granddaughter was still asleep. She woke her and asked for help getting dressed. Her hands were too weak for her to button her own clothes or tie her shoes. When she was completely dressed, she sent the girl to get her mother. She would need a ride to the hospital. She hadn’t been able to drive since she started seeing double. The events of the past few months had left the woman exhausted. First, she had seen her eye doctor. He took one look at her and told her that she had what’s called a third-nerve palsy. The muscles of the face and neck, he explained, are controlled by nerves that line up at the top of the spine. The nerve that controlled the eyelid, called the oculomotor nerve, was the third in this column. But he didn’t know what was affecting it or how to fix the problem. She needed to see a neuro-ophthalmologist, a doctor who specialized in the nerves that control the eyes. © 2021 The New York Times Company

Keyword: Movement Disorders; Neuroimmunology
Link ID: 27720 - Posted: 03.06.2021

By Susan Milius Grown-up giraffes just aren’t huggy, cuddling, demonstrative animals. So it took identity-recognition software grinding through five years of data to reveal that female social life matters to survival. The more gregarious adult female giraffes in northern Tanzania’s Tarangire ecosystem tend to live longer, concludes wildlife biologist Monica Bond of the University of Zurich. Females that typically hung around at least three others of their kind, were more likely to outlive those with fewer routine companions, Bond and colleagues report February 10 in Proceedings of the Royal Society B. In published science, the idea that giraffes even have social lives isn’t much more than a decade old, Bond says. (For the time being, Bond still treats giraffes as one species, Giraffa camelopardalis, until there’s more agreement on how many species there are.) Adult males spend most of their time in solitary searches for females willing to mate, but females often hang around in groups. Compared with bats clustering under a bridge or baboons grooming pals’ fur, even the most sociable female giraffes often look as if they just happen to be milling around feeding in the same shrubbery. These “loose” groups, as Bond describes them, don’t snuggle or groom each other. A group mostly just browses in the same vicinity, then may fray apart and reconfigure with different members in the fission-fusion pattern seen in many animals, such as dolphins. Yet closer looks have found that females, in their low-drama way, prefer certain neighbors and seem to avoid certain others. © Society for Science & the Public 2000–2021.

Keyword: Stress
Link ID: 27708 - Posted: 02.28.2021

By Cathleen O’Grady As Samuel West combed through a paper that found a link between watching cartoon violence and aggression in children, he noticed something odd about the study participants. There were more than 3000—an unusually large number—and they were all 10 years old. “It was just too perfect,” says West, a Ph.D. student in social psychology at Virginia Commonwealth University. Yet West added the 2019 study, published in Aggressive Behavior and led by psychologist Qian Zhang of Southwest University of Chongqing, to his meta-analysis after a reviewer asked him to cast a wider net. West didn’t feel his vague misgivings could justify excluding it from the study pool. But after Aggressive Behavior published West’s meta-analysis last year, he was startled to find that the journal was investigating Zhang’s paper while his own was under review. It is just one of many papers of Zhang’s that have recently been called into question, casting a shadow on research into the controversial question of whether violent entertainment fosters violent behavior. Zhang denies any wrongdoing, but two papers have been retracted. Others live on in journals and meta-analyses—a “major problem” for a field with conflicting results and entrenched camps, says Amy Orben, a cognitive scientist at the University of Cambridge who studies media and behavior. And not just for the ivory tower, she says: The research shapes media warning labels and decisions by parents and health professionals. © 2021 American Association for the Advancement of Science.

Keyword: Aggression; Development of the Brain
Link ID: 27695 - Posted: 02.17.2021

By Sabrina Imbler Over the course of her 32 years, Cheyenne the red-bellied lemur has had many soul mates. Her first was a mate in the traditional sense, a male red-bellied lemur who lived monogamously with Cheyenne for many years at the Duke Lemur Center in Durham, N.C. When he died, the elderly Cheyenne moved on to Geb, a geriatric crowned lemur; his young mate, Aria, had recently left him for a an even younger lemur. Cheyenne and Geb shared several years of peaceful, platonic companionship until Geb died in 2018 at the venerable age of 26. Cheyenne now lives with Chloris, a 32-year-old ring-tailed lemur who has full cataracts in one eye and arthritis in her tail. The two spend their days as many couples do, elderly or not: sleeping, hanging out, grooming each other and cuddling. “Right now Chloris and Cheyenne are snuggled up like a yin-yang symbol,” Britt Keith, the head lemur keeper, said on a call from the D wing of the center, which houses many of the center’s geriatric lemurs. The goal of Cheyenne and Chloris’s pairing is not for them to breed; the lemurs are both post-reproductive females. Rather, it is companionship, the comfort of having someone to spend your twilight days with and a soft body to snuggle up to at night — and, in Cheyenne and Chloris’s case, also during the day. “They sleep a lot,” Ms. Keith said. In the wild, lemurs generally do not want for company. Red-bellied lemurs form extremely tight, long-term bonds with their mates, and pairs rarely stray more than than three dozen feet apart, according to Stacey Tecot, a lemur primatologist at the University of Arizona. Crowned lemurs like Geb and ring-tailed lemurs like Chloris are not monogamous but have rich social lives, said Nicholas Grebe, a postdoctoral researcher who studies lemur behavior at Duke University and who knows Cheyenne and Chloris. © 2021 The New York Times Company

Keyword: Emotions; Pain & Touch
Link ID: 27692 - Posted: 02.15.2021

By Brooke N. Dulka Think back to years past. When you were a kid, you most likely had more friends than you do now. There were probably a lot of children on the playground you considered a friend, but not all of these friendships were very deep. As you grew up, your friendship circle most likely grew smaller. Instead of having many superficial relationships, you now have just a few really important friendships. This is normal. When we are older, we tend to focus on maintaining positive, meaningful relationships. One idea suggests that we become more selective about our friends because we become increasingly aware of our own mortality. In other words, we have future-oriented cognition. However, a recent study published in Science on the wild chimpanzees living in Uganda’s Kibale National Park suggests that our friendships may not actually be tied to thinking about the future. Alexandra Rosati, an evolutionary psychologist at the University of Michigan and one of the study’s lead investigators, had heard about this long-term field study in Uganda. “It seemed like it all could sort of fit together, in this cool way, this primatology data to actually test this idea about human cognition,” she says. Advertisement In this study, a team of researchers analyzed 78,000 hours of observations of 21 male chimpanzees made between 1995 and 2016 at the Kibale National Park. According to Rosati, a unique feature of this study is the value that exists in the long-term collection of data. “We used 20 years of data for this paper. [It] lets us look at this really detailed information about what's going on in these chimpanzees’ social lives,” she says. The findings surprised her. © 2021 Scientific American

Keyword: Stress; Development of the Brain
Link ID: 27681 - Posted: 02.08.2021

By Jason Castro Pursued by poets and artists alike, beauty is ever elusive. We seek it in nature, art and philosophy but also in our phones and furniture. We value it beyond reason, look to surround ourselves with it and will even lose ourselves in pursuit of it. Our world is defined by it, and yet we struggle to ever define it. As philosopher George Santayana observed in his 1896 book The Sense of Beauty, there is within us “a very radical and wide-spread tendency to observe beauty, and to value it.” Philosophers such as Santayana have tried for centuries to understand beauty, but perhaps scientists are now ready to try their hand as well. And while science cannot yet tell us what beauty is, perhaps it can tell us where it is—or where it isn’t. In a recent study, a team of researchers from Tsinghua University in Beijing and their colleagues examined the origin of beauty and argued that it is as enigmatic in our brain as it is in the real world. There is no shortage of theories about what makes an object aesthetically pleasing. Ideas about proportion, harmony, symmetry, order, complexity and balance have all been studied by psychologists in great depth. The theories go as far back as 1876—in the early days of experimental psychology—when German psychologist Gustav Fechner provided evidence that people prefer rectangles with sides in proportion to the golden ratio (if you’re curious, that ratio is about 1.6:1). © 2021 Scientific American

Keyword: Emotions; Vision
Link ID: 27675 - Posted: 02.03.2021

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 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 Jelena Kecmanovic Across the spectrum, mental health problems seem to be on the rise. One-quarter of Americans reported moderate to severe depression this summer and another quarter said they suffered from mild depression, a recent study reported. These findings are similar to surveys done by the Census Bureau and the Centers for Disease Control and Prevention. A third of Americans now show signs of clinical anxiety or depression, Census Bureau finds. Former first lady Michelle Obama highlighted the problem for many when she said in August that she has been dealing with “low-grade depression.” As a psychologist, I hear almost daily how the combination of coronavirus, racial unrest, economic uncertainty and political crisis are leading many people to feel a lot worse than usual. “It is not at all surprising that we are seeing the significant increase in distress. It’s a normal reaction to an abnormal situation,” said Judy Beck, president of the Beck Institute for Cognitive Behavior Therapy in Philadelphia and author of the widely used mental health textbook “Cognitive Behavior Therapy: Basics and Beyond.” But an important difference exists between having depressive symptoms — such as sadness, fatigue and loss of motivation — and a full-blown major depressive episode that can affect your ability to function at work and home for weeks or months. The amount and duration of the symptoms, as well as the degree to which they impair one’s life all play a role in diagnosing clinical depression. Extensive research suggests that certain ways of thinking and behaving can hasten the plunge into clinical depression, while others can prevent it. As we head into winter, which can stress the coping skills of many people, here are some strategies that can help you resist the depressive downward spiral. 1. Reduce overthinking. When we feel down, we tend to think about the bad things repeatedly, often trying to figure out why they’ve happened. Research shows that some people are especially prone to this kind of “depressive rumination.” They overanalyze everything, hoping to think their way out of feeling bad, and fret about consequences of their sadness.

Keyword: Depression; Emotions
Link ID: 27599 - Posted: 11.30.2020

Janet M. Gibson Amusement and pleasant surprises – and the laughter they can trigger – add texture to the fabric of daily life. Those giggles and guffaws can seem like just silly throwaways. But laughter, in response to funny events, actually takes a lot of work, because it activates many areas of the brain: areas that control motor, emotional, cognitive and social processing. As I found when writing “An Introduction to the Psychology of Humor,” researchers now appreciate laughter’s power to enhance physical and mental well-being. People begin laughing in infancy, when it helps develop muscles and upper body strength. Laughter is not just breathing. It relies on complex combinations of facial muscles, often involving movement of the eyes, head and shoulders. Laughter – doing it or observing it – activates multiple regions of the brain: the motor cortex, which controls muscles; the frontal lobe, which helps you understand context; and the limbic system, which modulates positive emotions. Turning all these circuits on strengthens neural connections and helps a healthy brain coordinate its activity. By activating the neural pathways of emotions like joy and mirth, laughter can improve your mood and make your physical and emotional response to stress less intense. For example, laughing may help control brain levels of the neurotransmitter serotonin, similar to what antidepressants do. By minimizing your brain’s responses to threats, it limits the release of neurotransmitters and hormones like cortisol that can wear down your cardiovascular, metabolic and immune systems over time. Laughter’s kind of like an antidote to stress, which weakens these systems and increases vulnerability to diseases. © 2010–2020, The Conversation US, Inc.

Keyword: Emotions; Neuroimmunology
Link ID: 27597 - Posted: 11.30.2020

By Bethany Brookshire A hungry brain craves food. A lonely brain craves people. After spending a day completely isolated from anyone else, people’s brains perked up at the sight of social gatherings, like a hungry person’s brain seeing food, scientists report November 23 in Nature Neuroscience. Cognitive neuroscientist Livia Tomova, then at MIT, and her colleagues had 40 participants fast for 10 hours. At the end of the day, certain nerve cells in the midbrain fired up in response to pictures of pizza and chocolate cake. Those neurons — in the substantia nigra pars compacta and ventral tegmental area — produce dopamine, a chemical messenger associated with reward (SN: 8/27/15). On a different day, the same people underwent 10 hours of isolation (no friends, no Facebook and no Instagram). That evening, neurons in the same spot activated in response to pictures of people chatting or playing team sports. The more hunger or isolation the subject reported, the stronger the effect (SN: 10/4/17). In people who reported that they were generally more lonely, the social responses were blunted. “We don’t really know what causes that,” Tomova says. “Maybe being isolated doesn’t really affect them as much, because it’s something that is not that different, perhaps, from their everyday life.” The midbrain, which plays an important role in people’s motivation to seek food, friends, gambling or drugs, responds to food and social signals even when people aren’t hungry or lonely. After all, a person always could eat or hang out. But hunger and loneliness increased the reaction and made people’s responses specific to the thing they were missing. The findings “speak to our current state,” says Tomova, now at the University of Cambridge. COVID-19 has left many more socially isolated, putting mental as well as physical health at stake (SN: 3/29/20) and leaving people with cravings for more than food. “It’s important to look at the social dimension of this kind of crisis.” L. Tomova et al. Acute social isolation evokes midbrain craving responses similar to hunger. Nature Neuroscience. Published online November 23, 2020. doi: 10.1038/s41593-020-00742-z. = © Society for Science & the Public 2000–2020

Keyword: Stress; Obesity
Link ID: 27594 - Posted: 11.27.2020

By Lisa Feldman Barrett Five hundred million years ago, a tiny sea creature changed the course of history: It became the first predator. It somehow sensed the presence of another creature nearby, propelled or wiggled its way over, and deliberately ate it. This new activity of hunting started an evolutionary arms race. Over millions of years, both predators and prey evolved more complex bodies that could sense and move more effectively to catch or elude other creatures. Eventually, some creatures evolved a command center to run those complex bodies. We call it a brain. This story of how brains evolved, while admittedly just a sketch, draws attention to a key insight about human beings that is too often overlooked. Your brain’s most important job isn’t thinking; it’s running the systems of your body to keep you alive and well. According to recent findings in neuroscience, even when your brain does produce conscious thoughts and feelings, they are more in service to the needs of managing your body than you realize. And in stressful times like right now, this curious perspective on your mental life may actually help to lessen your anxieties. Much of your brain’s activity happens outside your awareness. In every moment, your brain must figure out your body’s needs for the next moment and execute a plan to fill those needs in advance. For example, each morning as you wake, your brain anticipates the energy you’ll need to drag your sorry body out of bed and start your day. It proactively floods your bloodstream with the hormone cortisol, which helps make glucose available for quick energy. Your brain runs your body using something like a budget. A financial budget tracks money as it’s earned and spent. The budget for your body tracks resources like water, salt and glucose as you gain and lose them. Each action that spends resources, such as standing up, running, and learning, is like a withdrawal from your account. Actions that replenish your resources, such as eating and sleeping, are like deposits. The scientific name for body budgeting is allostasis. It means automatically predicting and preparing to meet the body’s needs before they arise. © 2020 The New York Times Company

Keyword: Stress
Link ID: 27593 - Posted: 11.27.2020

By Lindsay Gray When Herbert Weinstein stood trial for the murder of his wife in 1992, his attorneys were struck by the measured calm with which he recounted her death and the events leading up to it. He made no attempt to deny that he was culpable, and yet his stoicism in the face of his wildly uncharacteristic actions led his defense to suspect that he might not be. Weinstein underwent neuroimaging tests, which confirmed what his attorneys had suspected: a cyst had impinged upon large parts of Weinstein’s frontal lobe, the seat of impulse control in the brain. On these grounds, they reasoned he should be found not guilty by reason of insanity, despite Weinstein’s free admission of guilt. Guilt is difficult to define, but it pervades every aspect of our lives, whether we’re chastising ourselves for skipping a workout, or serving on the jury of a criminal trial. Humans seem to be hardwired for justice, but we’re also saddled with a curious compulsion to diagram our own emotional wiring. This drive to assign a neurochemical method to our madness has led to the generation of vast catalogs of neuroimaging studies that detail the neural underpinnings of everything from anxiety to nostalgia. In a recent study, researchers now claim to have moved us one step closer to knowing what a guilty brain looks like. Since guilt carries different weight depending on context or culture, the authors of the study chose to define it operationally as the awareness of having harmed someone else. A series of functional magnetic resonance imaging (fMRI) experiments across two separate cohorts, one Swiss and one Chinese, revealed what they refer to as a “guilt-related brain signature” that persists across groups. Since pervasive guilt is a common feature in severe depression and PTSD, the authors suggest that a neural biomarker for guilt could offer more precise insight into these conditions and, potentially, their treatment. But brain-based biomarkers for complex human behaviors also lend themselves to the more ethically fraught discipline of neuroprediction, an emergent branch of behavioral science that combines neuroimaging data and machine learning to forecast how an individual is likely to act based on how their brain scans compare to those of other groups. © 2020 Scientific American,

Keyword: Stress; Brain imaging
Link ID: 27591 - Posted: 11.21.2020

By Lisa Sanders, M.D. It started to drizzle just moments after the 24-year-old man crossed the finish line of the 2017 New York City Marathon. It was his first marathon, and he felt both elated and exhausted as the medal given for completing the brutal race was draped around his neck. A goody bag containing an energy drink was put in his left hand. It felt strangely heavy. His whole body ached and trembled with fatigue, but somehow that left arm felt even more tired. Unconcerned, he switched the bag to his right hand and went in search of his partner. Recovery took longer than he expected. It was a day and a half before his legs were strong enough for him to walk down stairs facing forward, rather than the sideways shuffle that his tired muscles insisted on. But by the end of the week he felt mostly normal. Only that left shoulder remained tired, sore and stiff. He went to a nearby walk-in clinic just south of City Hall. The nurse practitioner who examined him thought he had a rotator-cuff injury. She recommended a nonsteroidal anti-inflammatory like ibuprofen, physical therapy and time. The ibuprofen didn’t help much; neither did the physical therapy. That weekend he headed to the gym — his first workout since the race. He did his usual set of reps on his right biceps and triceps. But when he transferred the 25-pound dumbbell to his left hand, it seemed heavier. He struggled through two curls, but on the third the muscles in his arm turned wobbly. He grabbed the weight with his right hand and lowered it to the ground. By the time he got home, straightening his aching arm was excruciating, as if the muscles were too short to allow a full extension. That scared him. And it only got worse. The next day his whole arm was achy and tight. He couldn’t even work on his computer. Thinking back, the young runner questioned the assumption — shared by both him and the nurse practitioner — that the injury had occurred during the race. Now he suspected it started weeks earlier. © 2020 The New York Times Company

Keyword: Movement Disorders; Neuroimmunology
Link ID: 27587 - Posted: 11.21.2020

Diana Kwon It all began with a cough. Three years ago Tracey McNiven, a Scottish woman in her mid-30s, caught a bad chest infection that left her with a persistent cough that refused to subside, even after medication. A few months later strange symptoms started to appear. McNiven noticed numbness spreading through her legs and began to feel that their movement was out of her control. When she walked, she felt like a marionette, with someone else pulling the strings. Over the course of two weeks the odd loss of sensation progressively worsened. Then, one evening at home, McNiven's legs collapsed beneath her. “I was lying there, and I felt like I couldn't breathe,” she recalls. “I couldn't feel below my waist.” McNiven's mother rushed her to the hospital where she remained for more than half a year. During her first few weeks in the hospital, McNiven endured a barrage of tests as doctors tried to uncover the cause of her symptoms. It could be a progressive neurodegenerative condition such as motor neuron disease, they thought. Or maybe it was multiple sclerosis, a disease in which the body's own immune cells attack the nervous system. Bafflingly, however, the brain scans, blood tests, spinal taps and everything else came back normal. McNiven's predicament is not uncommon. According to one of the most comprehensive assessments of neurology clinics to date, roughly a third of patients have neurological symptoms that are deemed to be either partially or entirely unexplained. These may include tremor, seizures, blindness, deafness, pain, paralysis and coma and can parallel those of almost any neurological disease. In some patients, such complications can persist for years or even decades; some people require wheelchairs or cannot get out of bed. Although women are more often diagnosed than men, such seemingly inexplicable illness can be found in anyone and across the life span. © 2020 Scientific American

Keyword: Attention; Emotions
Link ID: 27586 - Posted: 11.18.2020

By Jessica Wapner We are living through an inarguably challenging time. The U.S. has been facing its highest daily COVID-19 case counts yet. Uncertainty and division continue to dog the aftermath of the presidential election. And we are heading into a long, cold winter, when socializing outdoors will be less of an option. We are a nation and a world under stress. But Andrew Huberman, a neuroscientist at Stanford University who studies the visual system, sees matters a bit differently. Stress, he says, is not just about the content of what we are reading or the images we are seeing. It is about how our eyes and breathing change in response to the world and the cascades of events that follow. And both of these bodily processes also offer us easy and accessible releases from stress. Huberman’s assertions are based on both established and emerging science. He has spent the past 20 years unraveling the inner workings of the visual system. In 2018, for example, his lab reported its discovery of brain pathways connected with fear and paralysis that respond specifically to visual threats. And a small but growing body of research makes the case that altering our breathing can alter our brain. In 2017 Mark Krasnow of Stanford University, Jack Feldman of the University of California, Los Angeles, and their colleagues identified a tight link between neurons responsible for controlling breathing and the region of the brain responsible for arousal and panic. This growing understanding of how vision and breathing directly affect the brain—rather than the more nebulous categories of the mind and feelings—can come in handy as we continue to face mounting challenges around the globe, across the U.S. and in our own lives. Scientific American spoke with Huberman about how it all works. © 2020 Scientific American

Keyword: Stress; Vision
Link ID: 27584 - Posted: 11.18.2020

By Catherine Zuckerman It’s 3 a.m. and you’ve been struggling for hours to fall asleep. Morning draws nearer and your anxiety about being exhausted the next day intensifies — yet again. If this sounds familiar, you’re not alone. Among the many disruptions of 2020, insomnia may rank high on the list. Data on how the pandemic has affected sleep is limited because biomedical research can take years to shake out and most studies to date have been small. But evidence from China and Europe suggests that prolonged confinement is altering sleep in adults as well as children. Doctors in the United States are seeing it too. “I think Covid and the election have affected sleep and could be considered a kind of trauma,” said Nancy Foldvary-Schaefer, director of the Cleveland Clinic Sleep Disorders Center. “A lot of people that I talk to — patients and non-patients and colleagues and family — have more anxiety generally now probably because of these two stressors, and high anxiety is clearly associated with insomnia.” Whether you’re suddenly tossing and turning at bedtime or waking up in the middle of the night, the first step toward better sleep is to figure out what’s triggering your insomnia. Once you do that, you can take action to prevent it from becoming chronic — a clinical sleep disorder that should be treated by a sleep-medicine specialist. Stressful and upsetting experiences like the death of a loved one or the loss of a job — two widespread realities of Covid-19 — are known psychological triggers for insomnia. If your insomnia is tied to such an event, the quickest way to get help is to call your doctor. One thing many doctors suggest is cognitive behavioral therapy, or C.B.T. C.B.T., or C.B.T.-I. for insomnia, is a standard treatment for both acute and chronic insomnia and includes a variety of techniques. Meditation, mindfulness and muscle relaxation can help people whose sleep problems are tied to a stressful event. C.B.T. for insomnia typically lasts from six to eight weeks and “works in about two-thirds to three-quarters of patients,” said Jennifer Martin, a psychologist and professor of medicine at the University of California, Los Angeles, David Geffen School of Medicine. © 2020 The New York Times Company

Keyword: Sleep; Stress
Link ID: 27581 - Posted: 11.16.2020

Alison Abbott Two years ago, immunologist and medical-publishing entrepreneur Leslie Norins offered to award US$1 million of his own money to any scientist who could prove that Alzheimer’s disease was caused by a germ. The theory that an infection might cause this form of dementia has been rumbling for decades on the fringes of neuroscience research. The majority of Alzheimer’s researchers, backed by a huge volume of evidence, think instead that the key culprits are sticky molecules in the brain called amyloids, which clump into plaques and cause inflammation, killing neurons. Norins wanted to reward work that would make the infection idea more persuasive. The amyloid hypothesis has become “the one acceptable and supportable belief of the Established Church of Conventional Wisdom”, says Norins. “The few pioneers who did look at microbes and published papers were ridiculed or ignored.” In large part, this was because some early proponents of the infection theory saw it as a replacement for the amyloid hypothesis. But some recent research has provided intriguing hints that the two ideas could fit together — that infection could seed some cases of Alzheimer’s disease by triggering the production of amyloid clumps. The data hint at a radical role for amyloid in neurons. Instead of just being a toxic waste product, amyloid might have an important job of its own: helping to protect the brain from infection. But age or genetics can interrupt the checks and balances in the system, turning amyloid from defender into villain. And that idea suggests new avenues to explore for potential therapies. To test the theory further, scientists are now developing animal models that mimic Alzheimer’s disease more closely. “We are taking the ideas seriously,” says neuroscientist Bart de Strooper, director of the UK Dementia Research Institute at University College London. © 2020 Springer Nature Limited

Keyword: Alzheimers; Neuroimmunology
Link ID: 27571 - Posted: 11.07.2020

The membranes surrounding our brains are in a never-ending battle against deadly infections, as germs constantly try to elude watchful immune cells and sneak past a special protective barrier called the meninges. In a study involving mice and human autopsy tissue, researchers at the National Institutes of Health and Cambridge University have shown that some of these immune cells are trained to fight these infections by first spending time in the gut. “This finding opens a new area of neuroimmunology, showing that gut-educated antibody-producing cells inhabit and defend regions that surround the central nervous system,” said Dorian McGavern, Ph.D., senior investigator at NINDS and co-senior author of the study, which was published in Nature. The central nervous system (CNS) is protected from pathogens both by a three-membrane barrier called the meninges and by immune cells within those membranes. The CNS is also walled off from the rest of the body by specialized blood vessels that are tightly sealed by the blood brain barrier. This is not the case, however, in the dura mater, the outermost layer of the meninges. Blood vessels in this compartment are not sealed, and large venous structures, referred to as the sinuses, carry slow moving blood back to the heart. The combination of slow blood flow and proximity to the brain requires strong immune protection to stop potential infections in their tracks. “The immune system has invested heavily in the dura mater,” said Dr. McGavern. “The venous sinuses within the dura act like drainage bins, and, consequently, are a place where pathogens can accumulate and potentially enter the brain. It makes sense that the immune system would set up camp in this vulnerable area.”

Keyword: Neuroimmunology
Link ID: 27569 - Posted: 11.07.2020

Elena Renken More than a century ago, the zoologist Richard Semon coined the term “engram” to designate the physical trace a memory must leave in the brain, like a footprint. Since then, neuroscientists have made progress in their hunt for exactly how our brains form memories. They have learned that specific brain cells activate as we form a memory and reactivate as we remember it, strengthening the connections among the neurons involved. That change ingrains the memory and lets us keep memories we recall more often, while others fade. But the precise physical alterations within our neurons that bring about these changes have been hard to pin down — until now. In a study published last month, researchers at the Massachusetts Institute of Technology tracked an important part of the memory-making process at the molecular scale in engram cells’ chromosomes. Neuroscientists already knew that memory formation is not instantaneous, and that the act of remembering is crucial to locking a memory into the brain. These researchers have now discovered some of the physical embodiment of that mechanism. The MIT group worked with mice that had a fluorescent marker spliced into their genome to make their cells glow whenever they expressed the gene Arc, which is associated with memory formation. The scientists placed these mice in a novel location and trained them to fear a specific noise, then returned them to this location several days later to reactivate the memory. In the brain area called the hippocampus, the engram cells that formed and recalled this memory lit up with color, which made it easy to sort them out from other brain cells under the microscope during a postmortem examination. All Rights Reserved © 2020

Keyword: Learning & Memory; Stress
Link ID: 27567 - Posted: 11.04.2020