Chapter 15. Emotions, Aggression, and Stress

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By Gina Kolata For decades, researchers have suspected that people infected with an exceedingly common virus, Epstein-Barr, might be more likely to develop multiple sclerosis, a neurological illness that affects a million people in the United States. Now, a team of researchers reports what some say is the most compelling evidence yet of a strong link between the two diseases. The virus infects nearly everyone in their teen or young adult years, and very few go on to develop multiple sclerosis. The researchers also note that it is not the only known risk factor for people who develop the illness. But they say their data points to it being the clearest of them all. While it remains to be seen whether the finding will result in treatments or cures for multiple sclerosis, the study may further motivate research into therapies and vaccines for the condition. In their study, published Thursday in Science, the group examined data from 10 million people on active duty in the United States Armed Forces over two decades. The strength of their study, said its principal investigator, Dr. Alberto Ascherio, an epidemiologist at the Harvard T.H. Chan School of Public Health, is that they were able to follow people for years and ask whether infections with Epstein-Barr preceded multiple sclerosis. Among the service members in the study, 801 developed multiple sclerosis, a disabling disease that occurs when the immune system attacks the fatty insulation that protects nerves in the brain and spinal cord. Most who develop the disease are diagnosed between the ages of 20 and 50. The disease is rare, though — an individual’s chance of getting multiple sclerosis is half of one percent. At the same time, the virus in question, Epstein-Barr, is common, infecting nearly everyone in the population at some point. Although few are aware that they were infected, some develop mononucleosis. The virus remains in the body for life. © 2022 The New York Times Company

Keyword: Multiple Sclerosis; Neuroimmunology
Link ID: 28154 - Posted: 01.15.2022

By JP O'Malley Neuroscientist Antonio Damasio believes that the link between brain and body is the key to understanding consciousness. In his latest book, Feeling & Knowing: Making Minds Conscious, he explains why. Consciousness is what gives an individual a sense of self; it helps one stay in the present, remember the past and plan for the future. Many scientists have argued that consciousness is created by vast networks of nerve cells, or neurons, in the brain. While it’s clear that the brain plays a major role in conscious experiences, it doesn’t act alone, argues Damasio, director of the University of Southern California’s Brain and Creativity Institute. Instead, he argues, consciousness is generated by a variety of structures within an organism, some neural, some not. What’s more, feelings — mental experiences of body states — help connect the brain to the rest of the body. “The feelings that we have of, say, hunger or thirst, or pain, or well-being, or desire, etc. — these are the foundation of our mind,” Damasio says. In his view, feelings have played a central role in the life-regulating processes of animals throughout the history of life. In Feeling & Knowing, Damasio suggests that consciousness evolved as a way to keep essential bodily systems steady. This concept is also known as homeostasis, a self-regulating process that maintains stability amid ever-changing conditions. Consciousness emerged as an extension of homeostasis, Damasio argues, allowing for flexibility and planning in complex and unpredictable environments. © Society for Science & the Public 2000–2022.

Keyword: Consciousness; Emotions
Link ID: 28141 - Posted: 01.08.2022

By David J. Linden When a routine echocardiogram revealed a large mass next to my heart, the radiologist thought it might be a hiatal hernia—a portion of my stomach poking up through my diaphragm to press against the sac containing my heart. “Chug this can of Diet Dr. Pepper and then hop up on the table for another echocardiogram before the soda bubbles in your stomach all pop.” So I did. However, the resulting images showed that the mass did not contain the telltale signature of bursting bubbles in my stomach that would support a hernia diagnosis. A few weeks later, an MRI scan, which has much better resolution, revealed that the mass was actually contained within the pericardial sac and was quite large—about the volume of that soda can. Even with this large invader pressing on my heart, I had no symptoms and could exercise at full capacity. I felt great. The doctors told me that the mass was most likely to be a teratoma, a clump of cells that is not typically malignant. Their outlook was sunny. Riffing on the musical South Pacific, my cardiologist said, “We’re gonna pop that orange right out of your chest and send you on your way.” While I was recovering from surgery, the pathology report came back and the news was bad—it wasn’t a benign teratoma after all, but rather a malignant cancer called synovial sarcoma. Because of its location, embedded in my heart wall, the surgeon could not remove all of the cancer cells. Doing so would have rendered my heart unable to pump blood. The oncologist told me to expect to live an additional six to 18 months. (c) 2022 by The Atlantic Monthly Group.

Keyword: Attention; Consciousness
Link ID: 28138 - Posted: 01.05.2022

Leonard Mlodinow Charles Darwin created the most successful theory in the history of biology: the theory of evolution. He was also responsible for another grand theory: the theory of emotion, which dominated his field for more than a century. That theory was dead wrong. The most important tenet of his theory was that the mind consists of two competing forces, the rational and the emotional. He believed emotions played a constructive role in the lives of non-human animals, but in humans emotions were a vestige whose usefulness had been largely superseded by the evolution of reason. We now know that, on the contrary, emotions enhance our process of reasoning and aid our decision-making. In fact, we can’t make decisions, or even think, without being influenced by our emotions. Consider a pioneering 2010 study in which researchers analysed the work of 118 professional traders in stocks, bonds and derivatives at four investment banks. Some were highly successful, but many were not. The researchers’ goal was to understand what differentiated the two groups. Their conclusion? They had different attitudes toward the role of emotion in their job. The relatively less successful traders for the most part denied that emotion played a significant role. They tried to suppress their emotions, while at the same time denying that emotions had an effect on their decision-making. The most successful traders, in contrast, had a different attitude. They showed a great willingness to reflect on their emotion-driven behaviour. They recognised that emotion and good decision-making were inextricably linked. Accepting that emotions were necessary for high performance, they “tended to reflect critically about the origin of their intuitions and the role of emotion”. © 2021 Guardian News & Media Limited

Keyword: Emotions; Learning & Memory
Link ID: 28136 - Posted: 01.05.2022

By Jane E. Brody You’re probably familiar with these major risk factors for heart disease: high blood pressure, high cholesterol, smoking, diabetes, obesity and physical inactivity. And chances are your doctor has checked you more than once for these risks and, I would hope, offered advice or treatment to help ward off a heart attack or stroke. But has your doctor also asked about the level of stress in your life? Chronic psychological stress, recent studies indicate, may be as important — and possibly more important — to the health of your heart than the traditional cardiac risk factors. In fact, in people with less-than-healthy hearts, mental stress trumps physical stress as a potential precipitant of fatal and nonfatal heart attacks and other cardiovascular events, according to the latest report. The new study, published in November in JAMA, assessed the fates of 918 patients known to have underlying, but stable, heart disease to see how their bodies reacted to physical and mental stress. The participants underwent standardized physical and mental stress tests to see if their hearts developed myocardial ischemia — a significantly reduced blood flow to the muscles of the heart, which can be a trigger for cardiovascular events — during either or both forms of stress. Then the researchers followed them for four to nine years. Among the study participants who experienced ischemia during one or both tests, this adverse reaction to mental stress took a significantly greater toll on the hearts and lives of the patients than did physical stress. They were more likely to suffer a nonfatal heart attack or die of cardiovascular disease in the years that followed. I wish I had known that in 1982, when my father had a heart attack that nearly killed him. Upon leaving the hospital, he was warned about overdoing physical stresses, like not lifting anything heavier than 30 pounds. But he was never cautioned about undue emotional stress or the risks of overreacting to frustrating circumstances, like when the driver ahead of him drove too slowly in a no-passing zone. © 2022 The New York Times Company

Keyword: Stress
Link ID: 28135 - Posted: 01.05.2022

By Molly Young Two distinguished academics walk into a restaurant in Manhattan. It is their first meeting — their first date, in fact — and the year is 2015. The man wears a down jacket against the icy winter evening. The woman has a shock of glossy white hair. The restaurant is on a cozy corner of the West Village and has foie gras on the menu. What the man doesn’t know is that the interior of his down jacket has suffered a structural failure, and the filling has massed along the bottom hem, forming a conspicuous bulge at his waist. As they greet each other, the woman perceives the bulge and asks herself: Is my date wearing a colostomy bag? They sit down to eat, but the woman is distracted. As they chat about their lives — former spouses, work, interests — the woman has “colostomy bag” on her mind. Is it or isn’t it? The two academics are of an age where such an intervention is, well, not exactly common, but not out of the realm of possibility. At the end of their dinner, the man takes the train back to Philadelphia, where he lives, and the woman returns to her apartment on the Upper West Side. Despite the enigma of the man’s midsection, the date is a success. It wasn’t until their third date that the question got resolved: no colostomy bag. “I was testing her,” Paul Rozin, one of the academics, later joked, “to see if she would put up with me.” (He wasn’t testing her. He was unaware of the bulge.) “I was worried,” said Virginia Valian, the other academic. It was fitting that an imaginary colostomy bag played a starring role in the couple’s first encounter. Paul Rozin is known for many things — he is an eminent psychologist who taught at the University of Pennsylvania for 52 years, and he has gathered honors and fellowships and published hundreds of influential papers and served on editorial boards and as chairman of the university’s department of psychology — but he is best known for his work on the topic of disgust. In the early 1980s, Rozin noticed that there was surprisingly little data available on this universal aspect of life. Odd, he thought, that of the six so-called basic emotions — anger, surprise, fear, enjoyment, sadness, disgust — the last had hardly been studied. © 2021 The New York Times Company

Keyword: Emotions
Link ID: 28129 - Posted: 12.29.2021

By Christof Koch A young Ernest Hemingway, badly injured by an exploding shell on a World War I battlefield, wrote in a letter home that “dying is a very simple thing. I’ve looked at death, and really I know. If I should have died it would have been very easy for me. Quite the easiest thing I ever did.” Years later Hemingway adapted his own experience—that of the soul leaving the body, taking flight and then returning—for his famous short story “The Snows of Kilimanjaro,” about an African safari gone disastrously wrong. The protagonist, stricken by gangrene, knows he is dying. Suddenly, his pain vanishes, and Compie, a bush pilot, arrives to rescue him. The two take off and fly together through a storm with rain so thick “it seemed like flying through a waterfall” until the plane emerges into the light: before them, “unbelievably white in the sun, was the square top of Kilimanjaro. And then he knew that there was where he was going.” The description embraces elements of a classic near-death experience: the darkness, the cessation of pain, the emerging into the light and then a feeling of peacefulness. Peace Beyond Understanding Near-death experiences, or NDEs, are triggered during singular life-threatening episodes when the body is injured by blunt trauma, a heart attack, asphyxia, shock, and so on. About one in 10 patients with cardiac arrest in a hospital setting undergoes such an episode. Thousands of survivors of these harrowing touch-and-go situations tell of leaving their damaged bodies behind and encountering a realm beyond everyday existence, unconstrained by the usual boundaries of space and time. These powerful, mystical experiences can lead to permanent transformation of their lives. © 2021 Scientific American,

Keyword: Consciousness; Stress
Link ID: 28123 - Posted: 12.22.2021

By Lisa Sanders, M.D. The 66-year-old man had just started his third lap at the community swimming pool outside Poughkeepsie, N.Y., when it struck. As he was turning his head to take a breath, an octopus of pain wrapped around the right side of his skull, starting at the joint where the jaw connects and slamming across his face and head with tentacles of squeezing agony. For a moment he was paralyzed — first with pain, then with fear. He couldn’t breathe; he could barely move. He struggled to the side of the pool and hung on, his breath ragged through involuntarily clenched teeth. His wife hurried over. He was a good swimmer; what was wrong? She saw his lips move and leaned closer. His jaw was clenched. “I can’t speak,” he mumbled. She helped him out of the pool. “We’re going to go to urgent care,” she said as she handed him a towel. These strange pains had been tormenting the man for nearly three weeks. It started as a headache that woke him from a dead sleep, a squeezing pressure deep inside his brain. He got up and took some acetaminophen. When he awoke the next morning, the headache was gone, but the regions around his head and face where the pressure had been strongest felt strangely tender. He couldn’t even brush his hair on the right side of his head. Bizarre as this was, he most likely would have soon forgotten about it except that it happened again the next night — and just about every night since. The pain in his jaw started a couple of days later. Opening and closing his mouth, and especially chewing, made his jaw throb. Eating anything more solid than mashed potatoes triggered excruciating pain. He went to his dentist, who poked and prodded. The only tenderness was in the joint where the jaw attached to the skull. It’s most likely TMJ, the dentist concluded — temporomandibular joint pain. That joint and the many attached muscles make speech and facial expressions possible. Lots of people have pain there, the dentist added. Bad habits like jaw-clenching and tooth-grinding aggravate the joint. The treatment is behavior modification to unlearn these habits, and sometimes a bite block, a custom-made piece of acrylic worn at night to protect teeth from injury. © 2021 The New York Times Company

Keyword: Pain & Touch; Neuroimmunology
Link ID: 28113 - Posted: 12.15.2021

Jeanne Paz Blocking an immune system molecule that accumulates after traumatic brain injury could significantly reduce the injury’s detrimental effects, according to a recent mouse study my neuroscience lab and I published in the journal Science. The cerebral cortex, the part of the brain involved in thinking, memory and language, is often the primary site of head injury because it sits directly beneath the skull. However, we found that another region near the center of the brain that regulates sleep and attention, the thalamus, was even more damaged than the cortex months after the injury. This may be due to increased levels of a molecule called C1q, which triggers a part of the immune system called the classical complement pathway. This pathway plays a key role in rapidly clearing pathogens and dead cells from the body and helps control the inflammatory immune response. C1q plays both helpful and harmful roles in the brain. On the one hand, accumulation of C1q in the brain can trigger abnormal elimination of synapses – the structures that allow neurons to communicate with one another – and contribute to neurodegenerative disease. On the other hand, C1q is also involved in normal brain development and protects the central nervous system from infection. In the case of traumatic brain injury, we found that C1q lingered in the thalamus at abnormally high levels for months after the initial injury and was associated with inflammation, dysfunctional brain circuits and neuronal death. This suggests that higher levels of C1q in the thalamus could contribute to several long-term effects of traumatic brain injury, such as sleep disruption and epilepsy. © 2010–2021, The Conversation US, Inc.

Keyword: Brain Injury/Concussion; Neuroimmunology
Link ID: 28112 - Posted: 12.15.2021

By Erin Blakemore Anger — such as road rage and the simmering displeasure of the ongoing pandemic — is the watchword for 2021. But be careful — those big emotions could trigger a stroke. FAQ: What to know about the omicron variant of the coronavirus Researchers in a global study devoted to figuring out stroke triggers found that about 1 in 11 stroke patients experience anger or emotional upset in the hour before their stroke symptoms begin. The study, published in the European Heart Journal, looked at data from 13,462 patients in 32 countries who had strokes. The patients completed extensive questionnaires during the first three days after they were hospitalized, answering questions about their medical history and what they had been doing and feeling before their stroke. Just over 8 percent of the patients surveyed said they had experienced anger or emotional upset within a day of symptom onset, which served as the control period. Just over 9 percent said they had been angry or upset within an hour of the first symptoms of their stroke, which was the test period. The risk of a stroke was higher in the test period when compared with the control period, the researchers said. “Our research found that anger or emotional upset was linked to an approximately 30% increase in risk of stroke during one hour after an episode — with a greater increase if the patient did not have a history of depression,” Andrew Smyth, a professor of clinical epidemiology at NUI Galway in Ireland who co-led the study, said in a statement. Lower education upped the odds of having a stroke linked with anger or emotional upset, as well.

Keyword: Stroke; Emotions
Link ID: 28109 - Posted: 12.15.2021

ByEmily Underwood Scientists have argued for decades over whether humans have pheromones, chemical compounds that trigger aggression and mating in insects and other animals. Although the notion has great popular appeal—search Amazon for “pheromone” and you’ll get the idea—there’s scant evidence for this kind of signal in our species. A new study could change that. Researchers have identified an odorless compound emitted by people—and in particular babies—called hexadecanal, or HEX, that appears to foster aggressive behavior in women and blunt it in men. “We cannot say that this is a pheromone,” says study author Noam Sobel, a neuroscientist at the Weizmann Institute of Science. “But we can say that it’s a molecule expressed by the human body that influences human behavior, specifically aggressive behavior, in a predicted manner.” Humans emit HEX from their skin, saliva, and feces, and it’s among the most abundant molecules babies emit from their heads. When researchers isolated the odorless compound and piped it into mouse cages, it had a relaxing effect on the animals, says Sobel, who studies the role of scent in human interactions. To test how HEX affects people, Eva Mishor, who earned her Ph.D. in Sobel’s lab, created a series of computer games designed to evoke intense frustration—and a measurable response to it—in 126 human participants. Half of the volunteers wore a HEX-infused adhesive strip on their upper lips while they played, whereas the other half wore strips that smelled identical but were HEX-free. In one task, participants negotiated with an unseen partner to divvy up a sum of virtual money. The participants thought they were playing with another person, but they were actually playing against computers. If a player offered their “partner” anything less than 90% of the whole amount, the computer rejected their proposals with a bright red “NO!” preventing them from earning any money. © 2021 American Association for the Advancement of Science.

Keyword: Chemical Senses (Smell & Taste); Aggression
Link ID: 28086 - Posted: 11.20.2021

Esther Landhuis Dogs that habitually hear a bell at chow time become classically conditioned to drool at the mere chime, as the physiologist Ivan Pavlov showed in the 1890s: Their brains learn to associate the bell with food and instruct the salivary glands to respond accordingly. More than a century later, in a paper published today in Cell, the neuroimmunologist Asya Rolls has shown that a similar kind of conditioning extends to immune responses. Using state-of-the-art genetic tools in mice, her team at the Technion in Haifa, Israel, identified brain neurons that became active during experimentally induced inflammation in the abdomen. Later, the researchers showed that restimulating those neurons could trigger the same types of inflammation again. “This is an outstanding body of work,” said Kevin Tracey, a neurosurgeon and president of the Feinstein Institutes for Medical Research in Manhasset, New York. It “establishes that the classic concept of immunological memory can be represented in neurons.” Others before Rolls have suggested that the brain could remember and retrieve immune responses, he said, but “she proved it.” Abstractions navigates promising ideas in science and mathematics. Journey with us and join the conversation. Ruslan Medzhitov, an immunologist at the Yale School of Medicine in New Haven, Connecticut, considers the new research “very provocative.” But unlike other groundbreaking studies that push boundaries and challenge conventional concepts, he said that this one also evokes “the ‘Oh, it makes sense’ type of reaction.” All Rights Reserved © 2021

Keyword: Neuroimmunology
Link ID: 28071 - Posted: 11.13.2021

By Raleigh McElvery While the brain and spinal cord have their own squad of specialized immune cells, the peripheral immune system is armed with a larger battalion of proteins, cells and entire organs, such as the spleen, that ward off invaders. Over the past decade, researchers have made great progress in understanding how the peripheral immune system affects neural activity: how immune signals that originate outside the central nervous system can affect cognitive processes, social behavior, neurodegeneration, and more. In fact, they have learned that immune cells from the periphery routinely patrol the central nervous system and support its function. In a new study, researchers showed for the first time that—just as the brain remembers people, places, smells, and so on—it also stores what they call “memory traces” of the body’s past infections. Reactivating the same brain cells that encode this information is enough to swiftly summon the peripheral immune system to defend at-risk tissues. In some ways, this is not an entire surprise. It is clear the peripheral immune system is capable of retaining information about past infections to fight off future ones—otherwise, vaccines would not work. But Asya Rolls, a neuroimmunologist at Technion–Israel Institute of Technology and the paper’s senior author, says the study expands this concept of classical immunologic memory. Initially, she was taken aback that the brain could store traces of immune activity and use them to trigger such a precise response. “I was amazed,” she says. Rolls’s team focused on a brain region called the insular cortex, which senses the body’s internal state through visceral signals such as temperature, pain, hunger and—the researchers reasoned—perhaps immune activity. They studied strains of mice with a type of gut inflammation known as colitis and used fluorescent markers to take snapshots of the groups of brain cells in the insular cortex that became active during the infection. © 2021 Scientific American

Keyword: Neuroimmunology
Link ID: 28069 - Posted: 11.09.2021

Sruthi S. Balakrishnan For nearly two decades, academic and industry researchers working to find ways to slow the progression of Alzheimer’s disease have focused chiefly on the amyloid-β plaques that accumulate among neurons. Dozens of clinical trials have tested drugs designed to remove or reduce these plaques, but successes have been few. Aducanumab, Biogen’s amyloid-attacking antibody drug (brand name Aduhelm) that was approved earlier this year following a long drought in new treatments for Alzheimer’s disease (AD), has been mired in controversy after scientists raised questions about the drug’s efficacy. This lack of progress has prompted many research groups to look instead at non-neuronal cells in the brain, and in particular, at immune cells known as microglia. Vital in both developing and mature brains, these cells help shape neurons, control how they communicate, keep an eye out for pathogenic intruders, and mediate neuroinflammation. This last role has emerged as particularly important as researchers uncover evidence that inflammation is linked to many neurological diseases—including AD—as well as to other conditions associated with aging. Many scientists have been waiting for the pharmaceutical industry to take notice of this link. “We knew all this ten years before, the rest of the world just didn’t pay attention to it,” says Jean Harry, a neurotoxicologist at the National Institute of Environmental Health Sciences in Durham, North Carolina. Key players in driving change have been recent genome-wide association studies (GWAS), which have pointed to AD–associated mutations in genes that are highly expressed in microglia, strengthening the evidence for links between these cells and the disease. “You can’t ignore it anymore,” says Bobbi Fleiss, a microglial neurobiologist at RMIT University in Melbourne, Australia. © 1986–2021 The Scientist.

Keyword: Glia; Neuroimmunology
Link ID: 28019 - Posted: 10.02.2021

By Sierra Carter Black women who have experienced more racism throughout their lives have stronger brain responses to threat, which may hurt their long-term health, according to a new study I conducted with clinical neuropsychologist Negar Fani and other colleagues. I am part of a research team that for more than 15 years has studied the ways stress related to trauma exposure can affect the mind and body. In our recent study, we took a closer look at a stressor that Black Americans disproportionately face in the United States: racism. My colleagues and I completed research with 55 Black women who reported how much they’d been exposed to traumatic experiences, such as childhood abuse and physical or sexual violence, and to racial discrimination, experiencing unfair treatment due to race or ethnicity. We asked them to focus on a task that required attention while simultaneously looking at stressful images. We used functional MRI to observe their brain activity during that time. We found that Black women who reported more experiences of racial discrimination had more response activity in brain regions that are associated with vigilance and watching out for threat — that is, the middle occipital cortex and ventromedial prefrontal cortex. Their reactions were above and beyond the response caused by traumatic experiences not related to racism. Our research suggests that racism had a traumalike effect on Black women’s health; being regularly attuned to the threat of racism can tax important body-regulation tools and worsen brain health.

Keyword: Stress; Brain Injury/Concussion
Link ID: 28015 - Posted: 10.02.2021

By Joshua Rapp Learn Giraffes don’t fight much, says Jessica Granweiler, a master’s student at the University of Manchester in England who studies nature’s tallest mammals. When they do, look out. “Fighting is extremely rare because it’s extremely violent,” Ms. Granweiler said. When older adult males joust for territory or mating rights, their hornlike pairs of ossicones thrust with the force of their long necks and can cut into their opponents’ flesh, wounding and sometimes even killing a combatant. But some forms of giraffe dueling serve other purposes. In a study published last month in the journal Ethology, Ms. Granweiler and her colleagues reported some discoveries about sparring behavior that help giraffes establish social hierarchies. They showed that the animals didn’t take advantage of smaller members of their herds, but rather practiced their head butts with males of similar stature in ways that to a human might even appear fair or honorable. Such findings could aid in the conservation of the dwindling populations of the animals. Ms. Granweiler and her colleagues observed social behavior in giraffes at the small Mogalakwena River Reserve in South Africa from November 2016 to May 2017. They began to record the details of these fights — basically a who-fought-who, and how in the giraffe world. They were surprised to find that giraffes, like humans, can be righties or southpaws when it comes to sparring. Even the youngest animals showed a clear preference, although unlike humans it seemed they were evenly split between lefties and righties. The researchers also noticed that the younger males sparred more with each other, and nearly always chose opponents similar in size to themselves — there wasn’t a lot of bullying going on. A bar brawl effect went on as well, where one sparring match seemed to infect the crowd and prompt more fights around them. © 2021 The New York Times Company

Keyword: Aggression; Sexual Behavior
Link ID: 27997 - Posted: 09.18.2021

by Giorgia Guglielmi Severe infections during early childhood are linked to autism — at least in some boys, a new study in mice and people suggests. The findings were published today in Science Advances. Researchers analyzed the health records of millions of children in the United States and found that boys diagnosed with autism are more likely than non-autistic boys to have had an infection requiring medical attention between age 1 and a half and 4. The study also showed that provoking a strong immune response in newborn mice with only one copy of TSC2, a gene tied to autism, leads to social memory problems in adult male rodents. In people, mutations in TSC2 cause tuberous sclerosis, a condition characterized by non-cancerous tumors and skin growths. About half of all people with tuberous sclerosis also have autism. “If the TSC2 mutation was sufficient to cause autism, then everyone with that mutation would have autism — but they don’t,” says senior investigator Alcino Silva, director of the Integrative Center for Learning and Memory at the University of California, Los Angeles. A child’s chances of having autism rise with severe infections in the child or his mother, previous studies show, but not all children who contract serious infections go on to be diagnosed with autism. The new study is the first to examine the relationship between immune activation and a specific genetic variant tied to autism, Silva says. The findings suggest that genetics and severe infection represent a ‘two-hit’ scenario for autism. © 2021 Simons Foundation

Keyword: Autism; Development of the Brain
Link ID: 27996 - Posted: 09.18.2021

By Lisa Sanders, M.D. The young woman was awakened by the screams of her 39-year-old husband. “Please make it stop!” he shouted, leaping from the bed. “It hurts!” He paced back and forth across the room, arms crossed over his chest as if to protect himself. Two days earlier, he had inhaled a breath mint when his wife startled him. He felt it move slowly down his throat as he swallowed repeatedly. His chest had hurt ever since. But not like this. The man squirmed miserably throughout the short drive to the emergency room at Westerly Hospital, near the Rhode Island and Connecticut border. No position was comfortable. Everything hurt. Even breathing was hard. Although the doctors in the E.R. immediately determined that the young man wasn’t having a heart attack, it was clear something was very wrong. His blood pressure was so low that it was hard to measure. A normal blood pressure may be 120/80. On arrival, his was 63/32. With a pressure this low, blood couldn’t get everywhere it was needed — a condition known as shock. His lips, hands and feet had a dusky hue from this lack of well-​oxygenated blood. He was given intravenous fluids to bring up his pressure, and when that didn’t work, he was started on medications for it. Three hours later, he was on two of these medicines and his fourth liter of fluid. Despite that, his pressure remained in the 70s. He had to be put on a breathing machine to help him keep up with his body’s demand for more oxygen. The most common cause of shock is infection. But this man, as sick as he was, had no signs of infection. The medical team started him on antibiotics anyway. Could the painful mint have torn his esophagus? Up to 50 percent of patients with that injury will die. A CT scan showed no evidence of perforation or of fluid in his chest. What else could this be? There was no sign of a clot keeping blood from entering the lungs, another cause of deadly low blood pressure. An ultrasound of the heart showed that he had some fluid in the sac called the pericardium, which contains and protects the heart, but not enough to interfere with how well it was beating. He was tested for Covid and for recreational drugs — both negative. © 2021 The New York Times Company

Keyword: Hormones & Behavior; Neuroimmunology
Link ID: 27981 - Posted: 09.08.2021

By Cara Giaimo Giraffes seem above it all. They float over the savanna like two-story ascetics, peering down at the fray from behind those long lashes. For decades, many biologists thought giraffes extended this treatment to their peers as well, with one popular wildlife guide calling them “aloof” and capable of only “the most casual” associations. Sign up for Science Times Get stories that capture the wonders of nature, the cosmos and the human body. Get it sent to your inbox. But more recently, as experts have paid closer attention to these lanky icons, a different social picture has begun to emerge. Female giraffes are now known to enjoy yearslong bonds. They have lunch buddies, stand guard over dead calves and stay close with their mothers and grandmothers. Females even form shared day care-like arrangements, called crèches, in which they take turns babysitting and feeding each others young. Observations like these have reached a critical mass, said Zoe Muller, a wildlife biologist who completed her Ph.D. at the University of Bristol in England. She and Stephen Harris, also at Bristol, recently reviewed hundreds of giraffe studies to look for broader patterns. Their analysis, published on Tuesday in the journal Mammal Review, suggests that giraffes are not loners, but socially complex creatures, akin to elephants or chimpanzees. They’re just a little more subtle about it. Dr. Muller’s sense of giraffes as secret socialites began in 2005, when she was researching her master’s thesis in Laikipia, Kenya. There to collect data on antelopes, she found herself drawn to the ganglier ungulates. “They are so weird to look at,” she said. “If somebody described them to you, you wouldn’t believe they even really existed.” After noticing that the same giraffes tended to spend time together — they looked “like teenagers hanging out,” she said — Dr. Muller started to read up on their lifestyles. “I was really surprised to see that all the scientific books said that they were completely non-sociable,” she said. “I thought, ‘Well, hang on. That’s not what I see at all.’” © 2021 The New York Times Company

Keyword: Evolution; Emotions
Link ID: 27945 - Posted: 08.11.2021

Max G. Levy Agony is contagious. If you drop a thick textbook on your toes, circuits in your brain’s pain center come alive. If you pick it up and accidentally drop it on my toes, hurting me, an overlapping neural neighborhood will light up in your brain again. “There's a physiological mechanism for emotional contagion of negative responses like stress and pain and fear,” says Inbal Ben-Ami Bartal, a neuroscientist at Tel-Aviv University in Israel. That's empathy. Researchers debate to this day whether empathy is a uniquely human ability. But more scientists are finding evidence suggesting it exists widely, particularly in social mammals like rats. For the past decade, Bartal has studied whether—and why—lab rodents might act on that commiseration to help pals in need. Picture two rats in a cage. One roams freely, while the other is constrained in a vented plexiglass tunnel with a small door that only opens from the outside. Bartal, along with teams at UC Berkeley and the University of Chicago, has shown that the free rat may feel their trapped fellow’s distress and learn to open the door. This empathic pull is so strong that rats will rescue their roommates instead of feasting on piles of chocolate chips. (Disclosure: I have three pet rats. My sources confirm that chocolate chips are borderline irresistible.) But there's been a catch: Bartal’s experiments over the years have shown that rats only help others they perceive as members of their social group—specific pals or entire genetic strains they recognize. So does this mean they can't empathize with strangers? In new results appearing in the journal eLife in July, Bartal and her adviser from Berkeley, Daniela Kaufer, uncovered a surprise. Rats do show the neural signatures of empathy for trapped strangers, but that alone isn’t enough to make them help. While seeing a trapped stranger lights up parts of the brain associated with empathy, only seeing a familiar rat or breed elicits a rush of activity in the brain’s so-called reward center, the nucleus accumbens—so only those rats get rescued. © 2021 Condé Nast

Keyword: Emotions; Evolution
Link ID: 27943 - Posted: 08.11.2021