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By Tom Zeller Jr. I have headaches. Not the low-grade, annoying, “I’ve got a headache” sort of headaches. I get those, too. Most everyone does, and they are a drag. No, when I say that I get headaches, I mean that at intervals that are largely unpredictable, a knot of pain rises deep inside my head, invariably sensed behind my right eyeball. It then swiftly clicks up through the intensity scale, racing past that dull ache you might get from staring at the screen too long, leapfrogging over that doozy you had the morning after your brother’s wedding, skipping past the agonizing-but-fleeting stab of an ice-cream headache, and arriving, within a matter of minutes, at a pain so piercing and sustained that I can only grip something sturdy, rock back and forth, and grunt until it subsides. Mine are what doctors call one of the “primary headaches” — recurring and often excruciating disorders that are not byproducts of another condition (or self-inflicted by last night’s cocktails), but relentless, and in many ways still poorly understood disorders unto themselves. We know them by common names like migraine, which affects tens of millions of Americans, disproportionately women. I suffer from another flavor known as cluster headaches (technically “trigeminal autonomic cephalalgias”). And there are others, with myriad and imperfectly drawn lines distinguishing them. If you experience migraines or cluster headaches — and research suggests that more than a billion people worldwide do — you probably know something about shuttling from doctor to doctor looking for someone who “gets it.” You know what it’s like to gladly gobble up pills that don’t really work and that leave you miserable in other ways. And you might even know the same sort of incredulous exasperation that has driven me to wonder, from my fetal position on the bathroom floor: “How is it possible that science can’t fix a damn headache?” © 2021 The New York Times Company

Keyword: Pain & Touch
Link ID: 27924 - Posted: 07.24.2021

Christie Wilcox One of the most well-studied synapses in the brain continues to surprise neuroscientists. According to a May 18 study in Nature Communications, mossy fiber synapses, so named because their terminals look a bit like moss growing on the axons, have an unexpected way of regulating the flow of information in the hippocampus: the postsynaptic cells that receive neurotransmitter signals can release their own glutamate to tamp down the transmission from the cell on the presynaptic side. This so-called retrograde signaling was totally unexpected and depends on calcium influx to the postsynaptic cell, meaning researchers might have to rethink the results of past experiments that used in vitro conditions with different calcium availability. The findings are “a big deal” for neuroscientists, says Chris McBain, a synaptic physiologist at the National Institutes of Health who was not involved in the study. “Retrograde glutamatergic signaling is a really rare occurrence in the central nervous system,” he notes, and to find it in mossy fibers “adds another layer of complexity onto one of the most complex synapses.” The researchers behind the new paper, led by neurophysiologist Peter Jonas of the Institute of Science and Technology Austria, were investigating the plasticity of hippocampal neurons, the dynamic changes in connections between cells that contribute to the functioning of neural circuits and that ultimately underlie learning, memory, and other cognitive abilities. János Szabadics, a neurophysiologist at the Institute of Experimental Medicine, Budapest, puts it quite simply: “Without synaptic plasticity, the brain would be just a bag of wires,” he says. © 1986–2021 The Scientist.

Keyword: Learning & Memory
Link ID: 27923 - Posted: 07.24.2021

Nidhi Subbaraman Maeve Wallace has studied maternal health in the United States for more than a decade, and a grim statistic haunts her. Five years ago, she published a study showing that being pregnant or recently having had a baby nearly doubles a woman’s risk of being killed1. More than half of the homicides she tracked, using data from 37 states, were perpetrated with a gun. In March 2020, she saw something she hadn’t seen before: a funding opportunity from the US National Institutes of Health (NIH) to study deaths and injuries from gun violence. She had mentioned firearms in her studies before. But knowing that the topic is politically fraught, she often tucked related terms and findings deep within her papers and proposals. This time, she says, she felt emboldened to focus on guns specifically, and to ask whether policies that restrict firearms for people convicted of domestic violence would reduce the death rate for new and expecting mothers. Male partners are the killers in nearly half of homicides involving women in the United States. “This call for proposals really motivated me to ask the research questions that I may not have otherwise asked,” says Wallace, an epidemiologist at Tulane University in New Orleans, Louisiana. Wallace’s group is one of several dozen funded by a new pool of federal money for gun-violence research in the United States, which has more firearm-related deaths than any other wealthy nation. Although other countries fund research on guns, it is often in the context of trafficking and armed conflict. US federal funding of gun-violence research has not reflected the death toll, researchers say. © 2021 Springer Nature Limited

Keyword: Aggression
Link ID: 27922 - Posted: 07.24.2021

Amanda Heidt Scientists have discovered two types of glial cells in the brains of adult mice—an astrocyte and an oligodendrocyte progenitor cell—after nudging neural stem cells to rise from dormancy, according to a study published June 10 in Science. The results suggest new roles for glial cells, best known for providing support to neurons, and could prompt a better understanding of how brains remain plastic into adulthood, when the vast majority of neurons no longer undergo cell division. This study is “a very important addition to the whole story about these fascinating [stem] cells that exist in the adult brain of rodents that have the capacity to generate new cells,” says Arturo Alvarez-Buylla, a developmental neuroscientist at the University of California, San Francisco, who was not involved in the work. “Understanding adult stem cells is fundamental to really know the kinds of plasticity that exist after the developmental period is over.” Most mammalian brain cells, be they neurons or glia, are generated during embryonic development, and reservoirs of stem cells become largely, if not entirely, dormant in adulthood. The small trickle of activity that is left can help the brain respond to change, sometimes by generating new neurons to help with learning or by producing cells in response to injury or disease. One pool exists in the brains of adult humans and mice, in an area called the ventricular-subventricular zone (V-SVZ). The walls of the two lateral ventricles, cavities filled with cerebrospinal fluid, are lined with stem cells, and along these walls, the cells have a regional identity—where a stem cell lies on the wall dictates what it differentiates into. This feature has been well-characterized for neuronal subtypes, which are synthesized within discrete domains on the lateral wall. Glial cells are known to be generated at low levels along the septal wall, but the specific subtypes remain unknown because the cells along this wall generally remain inactive. © 1986–2021 The Scientist.

Keyword: Development of the Brain; Neurogenesis
Link ID: 27921 - Posted: 07.24.2021

Amanda Heidt Takotsubo syndrome, also known as broken heart syndrome, is a rare, reversible condition with symptoms mimicking a mild heart attack. A disease that disproportionately affects women, TTS is triggered by stressful events such as bankruptcy, the death of a loved one, or divorce, and results in a weakening of the heart’s left ventricle such that it becomes temporarily misshapen. Previous work has shown that TTS patients have elevated activity in their amygdala, a brain region involved in stress response. What has never been clear, however, is whether “this activity in the brain happens as a result of the syndrome or whether it began many years before,” says Shady Abohashem, a nuclear cardiologist at Harvard Medical School. Abohashem and his colleagues retrospectively analyzed full-body PET/CT scans from 104 patients, most of whom had cancer and 41 of whom had developed TTS since first being scanned, and 63 individually matched controls. The team calculated ratios of the activity in each person’s amygdala to that of two brain regions that attenuate the stress response, the temporal lobe and the prefrontal cortex. Higher amygdala activity was associated with an increased risk for TTS, and among those with the condition, patients with higher ratios had developed TTS roughly two years earlier following the imaging than those with lower ratios. “We can now show that this syndrome happens as a result of chronic stress over years that makes you vulnerable to developing the syndrome more easily and sooner than [less stressed] people,” Abohashem says. © 1986–2021 The Scientist.

Keyword: Stress
Link ID: 27920 - Posted: 07.24.2021

By Pam Belluck, Sheila Kaplan and Rebecca Robbins Two months before the Food and Drug Administration’s deadline to decide whether to approve Biogen’s controversial Alzheimer’s drug, aducanumab, a council of senior agency officials resoundingly agreed that there wasn’t enough evidence it worked. The council, a group of 15 officials who review complex issues, concluded that another clinical trial was necessary before approving the drug. Otherwise, one council member noted, approval could “result in millions of patients taking aducanumab without any indication of actually receiving any benefit, or worse, cause harm,” according to minutes of the meeting, obtained by The New York Times. “It is critical that the decision be made from a place of certainty,” the minutes said. The session, whose details have not been reported before, represented at least the third time that proponents of approving aducanumab in the F.D.A. had received a clear message that the evidence did not convincingly show the drug could slow cognitive decline. On June 7, the F.D.A. greenlighted the drug anyway — a decision that has been met with scathing rebuke from many Alzheimer’s experts and other scientists and calls for investigations into how the agency approved a treatment that has little evidence it helps patients. How and why the F.D.A. went ahead and approved the drug — an intravenous infusion, marketed as Aduhelm, that the company has since priced at $56,000 a year — has become the subject of intense scrutiny. Two congressional committees are investigating the approval and the price. Much is still unknown, but an examination by The Times has found that the process leading to approval took several unusual turns, including a decision for the F.D.A. to work far more closely with Biogen than is typical in a regulatory review. Allegations about the collaboration prompted the F.D.A. to conduct an internal inquiry after a consumer advocacy group called for an inspector general’s investigation, according to documents reviewed by The Times. The agency has not disclosed the inquiry. © 2021 The New York Times Company

Keyword: Alzheimers
Link ID: 27919 - Posted: 07.21.2021

by Peter Hess Neurons in mice with an autism-linked mutation sprout extraneous protrusions, an overgrowth that tracks with above-average motor learning. The animals lose both attributes when treated with an experimental drug that suppresses the activity of the Ras-ERK/MAPK cell signaling pathway, according to a new study. This pathway helps reshape neurons to change the strength of their connections in response to learning or other influences, part of a process known as neuroplasticity. “There is a balance between learning and forgetting in the brain,” says lead researcher Stelios Smirnakis, associate professor of neurology at Harvard University. “Understanding these pathways and how to balance them is of critical importance to a number of neurological disorders.” Hyperactivation of the Ras-ERK/MAPK pathway, which is also involved in cell growth, has been linked to cancer as well as multiple autism-related conditions. “A lot of genes in that pathway have been shown to underlie several forms of autism,” says Maria Chahrour, assistant professor of neuroscience at the University of Texas Southwestern Medical Center in Dallas, who was not involved in the study. “The pathway itself is also dysregulated in several forms of autism, so there’s a potential convergence.” The mice in the new work had an extra copy of the gene MECP2. As in previous studies and some other autism mouse models, the MECP2-duplication mice showed enhanced motor learning, mastering how to balance on a rotating rod more quickly than their wildtype counterparts. The animals’ motor learning prowess offers a model for studying how the repetitive behaviors seen in people with autism develop, the researchers say. © 2021 Simons Foundation

Keyword: Autism; Genes & Behavior
Link ID: 27918 - Posted: 07.21.2021

By Kim Tingley During menopause, which marks the end of a woman’s menstrual cycles, her ovaries stop producing the hormones estrogen and progesterone, bringing an end to her natural childbearing years. But those hormones also regulate how the brain functions, and the brain governs their release — meaning that menopause is a neurological process as well. “Many of the symptoms of menopause cannot possibly be directly produced by the ovaries, if you think about the hot flashes, the night sweats, the anxiety, the depression, the insomnia, the brain fog,” says Lisa Mosconi, an associate professor of neurology at Weill Cornell Medicine and director of its Women’s Brain Initiative. “Those are brain symptoms, and we should look at the brain as something that is impacted by menopause at least as much as your ovaries are.” In June, Mosconi and her colleagues published in the journal Scientific Reports one of the few studies to observe in detail what happens to the brain throughout the menopause transition, not just before and after. Using various neuroimaging techniques, they scanned the brains of more than 160 women between the ages of 40 and 65 who were in different stages of the transition to examine the organ’s structure, blood flow, metabolism and function; they did many of the same scans two years later. They also imaged the brains of men in the same age range. “What we found in women and not in men is that the brain changes quite a lot,” Mosconi says. “The transition of menopause really leads to a whole remodeling.” On average, women in the United States enter the menopause transition — defined as the first 12 consecutive months without a period — at around 50; once diagnosed, they are in postmenopause. But they may begin to have hormonal fluctuations in their 40s. (For some women, this happens in their 30s, and surgical removal of the ovaries causes immediate menopause, as do some cancer treatments.) Those fluctuations cause irregular periods and potentially a wide variety of symptoms, including hot flashes, insomnia, mood swings, trouble concentrating and changes in sexual arousal. During this phase, known as perimenopause, which averages four years in length (but can last from several months to a decade), Mosconi and colleagues observed that their female subjects experienced a loss of both gray matter (the brain cells that process information) and white matter (the fibers that connect those cells). Postmenopause, however, that loss stopped, and in some cases brain volume increased, though not to its premenopausal size. © 2021 The New York Times Company

Keyword: Hormones & Behavior; Sexual Behavior
Link ID: 27917 - Posted: 07.21.2021

By Jonathan Lambert Winter on the Qinghai-Tibetan Plateau is unfriendly to pikas. Temperatures across the barren, windy highlands routinely dip below –30° Celsius, and the grass that typically sustains the rabbitlike mammals becomes dry and brittle. It would seem the perfect time for these critters to hibernate, or subsist on stores of grass in burrows to stay warm, like the North American pika. Instead, plateau pika (Ochotona curzoniae) continue foraging in winter, but reduce their metabolism by about 30 percent to conserve energy, researchers report July 19 in the Proceedings of the National Academy of Sciences. Some pikas also resort to unusual rations: yak poop. Camera data from four sites confirmed that pikas regularly brave the cold to forage. “Clearly they’re doing something fancy with their metabolism that’s not hibernation,” says John Speakman, an ecophysiologist at the University of Aberdeen in Scotland. Speakman and colleagues measured daily energy expenditure of 156 plateau pikas in summer and winter, and implanted 27 animals with temperature sensors. While many nonhibernating animals keep warm in winter by using more energy, these pikas did the opposite (SN: 1/22/14). On average, pikas reduced their metabolism by 29.7 percent, in part by cooling their bodies a couple degrees overnight. The animals were also less active, relative to summertime levels. © Society for Science & the Public 2000–2021.

Keyword: Obesity
Link ID: 27916 - Posted: 07.21.2021

By Gretchen Reynolds We all know that lifting weights can build up our muscles. But by changing the inner workings of cells, weight training may also shrink fat, according to an enlightening new study of the molecular underpinnings of resistance exercise. The study, which involved mice and people, found that after weight training, muscles create and release little bubbles of genetic material that can flow to fat cells, jump-starting processes there related to fat burning. The results add to mounting scientific evidence that resistance exercise has unique benefits for fat loss. They also underscore how extensive and interconnected the internal effects of exercise can be. Many of us pigeonhole resistance training as muscle building, and with good reason. Lifting weights — or working against our body weight as we bob through push-ups, squats or chair dips — will noticeably boost our muscles’ size and strength. But a growing number of studies suggest weight training also reshapes our metabolisms and waistlines. In recent experiments, weight workouts goosed energy expenditure and fat burning for at least 24 hours afterward in young women, overweight men and athletes. Likewise, in a study I covered earlier this month, people who occasionally lifted weights were far less likely to become obese than those who never lifted. But how weight training revamps body fat remains murky. Part of the effect occurs because muscle is metabolically active and burns calories, so adding muscle mass by lifting should increase energy expenditure and resting metabolic rates. After six months of heavy lifting, for example, muscles will burn more calories just because they are larger. But that doesn’t fully explain the effect, because adding muscle mass requires time and repetition, while some of the metabolic effects of weight training on fat stores seem to occur immediately after exercise. © 2021 The New York Times Company

Keyword: Obesity
Link ID: 27915 - Posted: 07.21.2021

By Linda Searing Keeping your brain active later in life may delay by as much as five years the onset of Alzheimer’s disease, the most common type of dementia. Research published in the journal Neurology found that cognitively stimulating activities that involve seeking or processing information — such as reading books, magazines or newspapers, writing letters, playing card games, board games or checkers, and doing puzzles — seemed to add dementia-free time to older people’s lives. The research involved 1,903 people (average age was 80), none of whom had dementia at the start of the study and who were tracked and tested for up to 22 years. In that time, 457 participants developed Alzheimer’s. That occurred on average at age 94 for people who did the most brain-stimulating activities later in life, compared with developing Alzheimer’s at age 89 for those with the least amount of cognitive activity. Alzheimer’s, considered a degenerative brain disease, affects memory, thinking and behavior, with symptoms eventually becoming severe enough to interfere with once-routine daily tasks. Today, about 6.2 million Americans 65 and older have the disease, two-thirds of them women, according to the Alzheimer’s Association. That number is expected to reach nearly 13 million by 2050, unless ways are discovered to prevent, cure or slow the disease. The researchers found that neither education nor cognitive activity early in life were associated with the age at which a person developed Alzheimer’s. Rather, it’s what you do later in life that seems to make a difference. And, as the lead author of the story said, “It’s never too late to start doing the kinds of inexpensive, accessible activities” tracked in the study, “even in your 80s.”

Keyword: Alzheimers; Learning & Memory
Link ID: 27914 - Posted: 07.21.2021

By Pam Belluck He has not been able to speak since 2003, when he was paralyzed at age 20 by a severe stroke after a terrible car crash. Now, in a scientific milestone, researchers have tapped into the speech areas of his brain — allowing him to produce comprehensible words and sentences simply by trying to say them. When the man, known by his nickname, Pancho, tries to speak, electrodes implanted in his brain transmit signals to a computer that displays his intended words on the screen. His first recognizable sentence, researchers said, was, “My family is outside.” The achievement, published on Wednesday in the New England Journal of Medicine, could eventually help many patients with conditions that steal their ability to talk. “This is farther than we’ve ever imagined we could go,” said Melanie Fried-Oken, a professor of neurology and pediatrics at Oregon Health & Science University, who was not involved in the project. Three years ago, when Pancho, now 38, agreed to work with neuroscience researchers, they were unsure if his brain had even retained the mechanisms for speech. “That part of his brain might have been dormant, and we just didn’t know if it would ever really wake up in order for him to speak again,” said Dr. Edward Chang, chairman of neurological surgery at University of California, San Francisco, who led the research. The team implanted a rectangular sheet of 128 electrodes, designed to detect signals from speech-related sensory and motor processes linked to the mouth, lips, jaw, tongue and larynx. In 50 sessions over 81 weeks, they connected the implant to a computer by a cable attached to a port in Pancho’s head, and asked him to try to say words from a list of 50 common ones he helped suggest, including “hungry,” “music” and “computer.” As he did, electrodes transmitted signals through a form of artificial intelligence that tried to recognize the intended words. © 2021 The New York Times Company

Keyword: Brain imaging; Language
Link ID: 27913 - Posted: 07.17.2021

By Elizabeth Pennisi In hyenas as well as humans, it pays to be born to high-ranking parents. A new study reveals how power is passed down in these matriarchal mammals: Elite hyena cubs cultivate their mom’s friends, who help keep them fed and protected throughout their lives. The work drives home the role moms and dads play in shaping the social world of their children, says Josh Firth, a social networks researcher at the University of Oxford who was not involved with the study. “We tend to think about who we are connected to as a product of our doing, but it’s a product of our parents as well.” Chimpanzees, hyenas, and other social animals live in hierarchical societies. Those at the top eat first, and are typically surrounded by a gang that protects them from other members of their species that try to challenge their status. High rank tends to be inherited, but it’s been unclear how subsequent generations end up with the same type of ruling clan their parents do. Do they recruit their own powerful allies, or inherit them? Erol Akçay, a theoretical biologist at the University of Pennsylvania, and behavioral ecologist Amiyaal Ilany, now at Bar-Ilan University, decided to analyze the work of Kay Holekamp. A behavioral ecologist at Michigan State University, Holekamp’s team had been following the lives of a clan of spotted hyenas (Crocuta crocuta) in Kenya for almost 30 years. Day after day, the researchers have recorded the activity of the hyenas, including their interactions with and proximity to other hyenas, to understand the species’ behavior and ecology. They have also kept track of the pedigrees and social status of each female and its offspring. © 2021 American Association for the Advancement of Science.

Keyword: Aggression; Sexual Behavior
Link ID: 27912 - Posted: 07.17.2021

Tanya T. Nguyen, M.D., Dilip V. Jeste, M.D. In James Hilton’s 1933 novel Lost Horizons, Shangri-La was a magical utopia where people lived well beyond 100 years. But now, less than a century later, it seems we are well on our way to making Hilton’s vision a reality. The US Census Bureau reported in 2020 that the average life expectancy has increased from 47 in 1900 to over 80 years today, while the number of people over age 60 exceeds children under 15 for the first time ever. By 2060, the average lifespan will approach 90 years. Astonishingly, more than half of the babies born today will live to age 100 and beyond, which will make Hilton’s seemingly far-fetched vision come to pass. One might think that people living longer would represent an enormous, thrilling milestone. But unfortunately, aging is rarely perceived that way. The increase in older people—metaphorically termed a “silver tsunami” since the 1980s—has economic implications, including unimaginable healthcare costs. Certain segments of western culture sadly equate aging with such “d” words as degeneration, decline, disability, diseases, dementia, depression, and death. Policy makers and economists are outspoken in their fear that spending money on older people’s care will mean less money for children and younger adults, who represent the future. This attitude—commonly labeled ageism—is analogous to such phenomena as sexism, racism, and bias against certain sexual orientations. Ageism has made many older people feel guilty about living longer and becoming a potential burden. They think—and are encouraged by society to think—that aging is an incurable disease. © 2021 The Dana Foundation.

Keyword: Development of the Brain
Link ID: 27911 - Posted: 07.17.2021

Researchers at the University of Chicago and Argonne National Laboratory have imaged an entire mouse brain across five orders of magnitude of resolution, a step which researchers say will better connect existing imaging approaches and uncover new details about the structure of the brain. The advance, which was published on June 9 in NeuroImage, will allow scientists to connect biomarkers at the microscopic and macroscopic level. It leveraged existing advanced X-ray microscopy techniques to bridge the gap between MRI and electron microscopy imaging, providing a viable pipeline for multiscale whole brain imaging within the same brain. “Our lab is really interested in mapping brains at multiple scales to get an unbiased description of what brains look like,” said senior author Narayanan “Bobby” Kasthuri, assistant professor of neurobiology at UChicago and scientist at Argonne. “When I joined the faculty here, one of the first things I learned was that Argonne had this extremely powerful X-ray microscope, and it hadn’t been used for brain mapping yet, so we decided to try it out.” The microscope uses a type of imaging called synchrotron-based X-ray tomography, which can be likened to a “micro-CT”, or micro-computerized tomography scan. Thanks to the powerful X-rays produced by the synchrotron particle accelerator at Argonne, the researchers were able to image the entire mouse brain—roughly one cubic centimeter—at the resolution of a micron, 1/10,000 of a centimeter. It took roughly six hours to collect images of the entire brain, adding up to around 2 terabytes of data. This is one of the fastest approaches for whole brain imaging at this level of resolution.

Keyword: Brain imaging
Link ID: 27910 - Posted: 07.17.2021

By Emily Anthes Johnson & Johnson’s beleaguered Covid-19 vaccine may be associated with a small increased risk of Guillain–Barré syndrome, a rare but potentially serious neurological condition, federal officials said on Monday. The Food and Drug Administration has added a warning about the potential side effect to its fact sheets about the vaccine. The risk appears to be very small. So far, there have been 100 reports of the syndrome in people who had received the Johnson & Johnson vaccine. Nearly 13 million doses of the vaccine have been administered in the United States. Here are answers to some common questions about the syndrome and its connection to vaccination. What is Guillain-Barré syndrome? Guillain-Barré is a rare condition in which the body’s immune system attacks nerve cells. It can cause muscle weakness and paralysis. Although the symptoms often pass within weeks, in some cases, the condition can cause permanent nerve damage. In the United States, there are typically 3,000 to 6,000 cases of the syndrome per year, according to the Centers for Disease Control and Prevention. It is most common in adults over 50. The precise cause of the syndrome is unknown, but in many cases the condition follows another illness or infection, such as the flu. It has also been reported in people with Covid-19. This is not the first vaccine that has been linked to Guillain-Barré, although the risk appears to be tiny. A large swine flu vaccination campaign in 1976 led to a small uptick in the incidence of syndrome; the vaccine caused roughly one extra case of Guillain-Barré for every 100,000 people vaccinated. The seasonal flu shot is associated with roughly one to two additional cases for every million vaccines administered. © 2021 The New York Times Company

Keyword: Movement Disorders; Neuroimmunology
Link ID: 27909 - Posted: 07.14.2021

By Melissa J. Coleman, Eric Fortune A fundamental feature of vocal communication is taking turns: when one person says something, the other person listens and then responds. Turn-taking requires precise coordination of the timing of signals between individuals. We have all found over the past year communicating over Zoom that disruptions of the timing of auditory cues—like those annoying delays caused by poor connections—make effective communication difficult and frustrating. How do the brains of two individuals synchronize their activity patterns for rapid turn-taking during vocal communication? We addressed this question in a recently published paper by studying turn-taking in a specialist, the plain-tailed wren (Pheugopedius euophrys), which sings precisely timed duets. Our findings demonstrate the ability to coordinate relies on sensory cues from one partner that temporarily inhibit vocalizations in the other. These birds sing duets in which females and males alternate their vocalizations, called syllables, so rapidly it sounds as if a single bird is singing. These wrens live in dense bamboo on the slopes of the Andes. To study the neural basis of duet singing, we flew to Ecuador where we loaded up a truck with equipment and drove to a remote field-site called the Yanayacu Biological Field Station and Center for Creative Studies. Much of our equipment required electricity, so we had to bring car batteries for backup and used a six-meter copper rod that we drove into the soft mountain earth for our electrical ground. Our “lab bench” was a door that we placed on two Pelican suitcases. First, we had to catch pairs of wrens, so we hacked through bamboo with machetes and set up mist nets. We then attracted pairs to the nets by playing the duets of wrens. To see how neurons responded during duets, we surgically implanted very small wires into a specific region of the brain, called HVC. Neurons in this region are responsible for producing the song—that is, they are premotor—and they also respond to auditory signals. To transmit the neural signals (i.e., action potentials) to a computer, a small wireless digital transmitter was then connected to the wires. We then had to wait for the birds to sing their remarkable duets. © 2021 Scientific American,

Keyword: Animal Communication; Language
Link ID: 27908 - Posted: 07.14.2021

By Michael Pollan After a half century spent waging war on drugs, Americans seem ready to sue for peace. The 2020 elections brought plenty of proof that voters have leapt ahead of politicians in recognizing both the failures of the drug war and the potential of certain illicit drugs as powerful tools for healing. Ballot initiatives in five states — four of them traditionally red — legalized some form of cannabis use. By substantial margins, Oregon passed two landmark drug reform initiatives: Fifty-nine percent of voters supported Measure 110, which decriminalized the possession of small quantities of all drugs, even hard ones like heroin and cocaine. A second proposal, Measure 109, specifically legalized psilocybin therapy, directing the state’s health department to license growers of so-called magic mushrooms and train facilitators to administer them beginning in 2023. In the past two years, a new drug policy reform movement called Decriminalize Nature has persuaded local governments in a half dozen municipalities, including Washington, D.C., to decriminalize “plant medicines” such as psilocybin, ayahuasca, iboga and the cactuses that produce mescaline. Last month, the California State Senate passed a bill that would make legal the personal possession, use and “social sharing” of psychedelics, including LSD and MDMA, a.k.a. Ecstasy or Molly. Political opposition to all these measures has been notably thin. Neither party, it seems, has the stomach for persisting in a war that has achieved so little while doing so much damage, especially to communities of color and our civil liberties. But while we can now begin to glimpse an end to the drug war, it is much harder to envision what the drug peace will look like. How will we fold these powerful substances into our society and our lives so as to minimize their risks and use them most constructively? The blunt binaries of “Just say no” that have held sway for so long have kept us from having this conversation and from appreciating how different one illicit drug is from another. © 2021 The New York Times Company

Keyword: Drug Abuse; Depression
Link ID: 27907 - Posted: 07.14.2021

By Jaime Chambers Wiggles and wobbles and a powerful pull toward people — that’s what 8-week-old puppies are made of. From an early age, dogs outpace wolves at engaging with and interpreting cues from humans, even if the dogs have had less exposure to people, researchers report online July 12 in Current Biology. The result suggests that domestication has reworked dogs’ brains to make the pooches innately drawn to people — and perhaps to intuit human gestures. Compared with human-raised wolf pups, dog puppies that had limited exposure to people were still 30 times as likely to approach a strange human, and five times as likely to approach a familiar person. “I think that is by far the clearest result in the paper, and is powerful and meaningful,” says Clive Wynne, a canine behavioral scientist at Arizona State University in Tempe who was not involved in the study. Wolf pups are naturally less entranced by people than dogs are. “When I walked into the [wolf] pen for the first time, they would all just run into the corner and hide,” says Hannah Salomons, an evolutionary anthropologist studying dog cognition at Duke University. Over time, Salomons says, most came to ignore her, “acting like I was a piece of furniture.” But dogs can’t seem to resist humans’ allure (SN: 7/19/17). They respond much more readily to people, following where a person points, for example. That ability may seem simple, but it’s a skill even chimpanzees — humans’ close relatives — don’t show. Human babies don’t learn how to do it until near their first birthday. © Society for Science & the Public 2000–2021

Keyword: Evolution; Learning & Memory
Link ID: 27906 - Posted: 07.14.2021

By Gretchen Reynolds Exercise can freshen and renovate the white matter in our brains, potentially improving our ability to think and remember as we age, according to a new study of walking, dancing and brain health. It shows that white matter, which connects and supports the cells in our brains, remodels itself when people become more physically active. In those who remain sedentary, on the other hand, white matter tends to fray and shrink. The findings underscore the dynamism of our brains and how they constantly transform themselves — for better and worse — in response to how we live and move. The idea that adult brains can be malleable is a fairly recent finding, in scientific terms. Until the late 1990s, most researchers believed human brains were physically fixed and inflexible after early childhood. We were born, it was thought, with most of the brain cells we would ever have and could not make more. In this scenario, the structure and function of our brains would only decline with age. But science advanced, thankfully, and revised that gloomy forecast. Complex studies using specialized dyes to identify newborn cells indicated that some parts of our brains create neurons deep into adulthood, a process known as neurogenesis. Follow-up studies then established that exercise amplifies neurogenesis. When rodents run, for example, they pump out three or four times as many new brain cells as inactive animals, while in people, beginning a program of regular exercise leads to greater brain volume. In essence, this research shows, our brains retain lifelong plasticity, changing as we do, including in response to how we exercise. These past studies of brain plasticity generally focused on gray matter, though, which contains the celebrated little gray cells, or neurons, that permit and create thoughts and memories. Less research has looked at white matter, the brain’s wiring. Made up mostly of fat-wrapped nerve fibers known as axons, white matter connects neurons and is essential for brain health. But it can be fragile, thinning and developing small lesions as we age, dilapidations that can be precursors of cognitive decline. Worryingly, it also has been considered relatively static, with little plasticity, or ability to adapt much as our lives change. © 2021 The New York Times Company

Keyword: Learning & Memory; Alzheimers
Link ID: 27905 - Posted: 07.14.2021