Max Kozlov A group of brain cells in mice becomes active both when the animals fight and when they watch other mice fight, a study1 shows. The work hints that such ‘mirror neurons’, which fire when an animal either observes or takes part in a particular activity, could shape complex social behaviours, such as aggression. The mirror neurons described in the study are the first to be found in the hypothalamus, an evolutionarily ancient brain region — suggesting that mirror neurons’ original purpose might have been to enhance defence and, ultimately, reproductive success, the authors speculate. The study was published in Cell on 15 February. “We’ve now shown that mirror neurons functionally participate in the behaviours they’re mirroring,” says Nirao Shah, a neuroscientist at Stanford University in California who co-authored the study. “That changes what we think about mirror neurons.” First identified in monkeys in the 1990s, mirror neurons generally fire when an animal takes a certain action, but they also fire when it sees another animal perform the same action. Previous work has linked mirror neurons’ activity to simple behaviours, such as reaching for an object, but not to complex social behaviours, such as fighting. But exactly how mirror-neuron activity contributes to cognitive functions has been controversial, says Pier Francesco Ferrari, a neuroethologist at the Institute of Cognitive Science Marc Jeannerod in Lyon, France. Some researchers have argued that the fact that mirror neurons fire both when an animal observes a behaviour and when it performs that behaviour itself shows that these neurons are involved in a higher-order awareness of others’ actions — and perhaps even contribute to empathy. But others say that there is little evidence to support this theory. © 2023 Springer Nature Limited

Keyword: Aggression; Attention
Link ID: 28674 - Posted: 02.18.2023

By McKenzie Prillaman Psychedelics go beneath the cell surface to unleash their potentially therapeutic effects. These drugs are showing promise in clinical trials as treatments for mental health disorders (SN: 12/3/21). Now, scientists might know why. These substances can get inside nerve cells in the cortex — the brain region important for consciousness — and tell the neurons to grow, researchers report in the Feb. 17 Science. Several mental health conditions, including depression and post-traumatic stress disorder, are tied to chronic stress, which degrades neurons in the cortex over time. Scientists have long thought that repairing the cells could provide therapeutic benefits, like lowered anxiety and improved mood. Psychedelics — including psilocin, which comes from magic mushrooms, and LSD — do that repairing by promoting the growth of nerve cell branches that receive information, called dendrites (SN: 11/17/20). The behavior might explain the drugs’ positive outcomes in research. But how they trigger cell growth was a mystery. It was already known that, in cortical neurons, psychedelics activate a certain protein that receives signals and gives instructions to cells. This protein, called the 5-HT2A receptor, is also stimulated by serotonin, a chemical made by the body and implicated in mood. But a study in 2018 determined that serotonin doesn’t make these neurons grow. That finding “was really leaving us scratching our heads,” says chemical neuroscientist David Olson, director of the Institute for Psychedelics and Neurotherapeutics at the University of California, Davis. © Society for Science & the Public 2000–2023.

Keyword: Drug Abuse; Depression
Link ID: 28673 - Posted: 02.18.2023

Jane Clinton For those of us who struggle to leave our beds in the winter, taunts of “lazy” could well be misplaced. New research suggests that while humans do not hibernate, we may need more sleep during the colder months. Analysis of people undergoing sleep studies found that people get more REM (rapid eye movement) sleep in the winter. While total sleep time appeared to be about an hour longer in the winter than the summer, this result was not considered statistically significant. However, REM sleep – known to be directly linked to the circadian clock, which is affected by changing light – was 30 minutes longer in the winter than in summer. The research suggests that even in an urban population experiencing disrupted sleep, humans experience longer REM sleep in winter than summer and less deep sleep in autumn. Researchers say if the study’s findings can be replicated in people with healthy sleep, this would provide the first evidence for a need to adjust sleep habits to season – perhaps by going to sleep earlier in the darker and colder months. Dr Dieter Kunz, corresponding author of the study, based at the Clinic for Sleep & Chronomedicine at the St Hedwig hospital, Germany, said: “Seasonality is ubiquitous in any living being on this planet. “Even though we still perform unchanged over the winter, human physiology is down-regulated, with a sensation of ‘running-on-empty’ in February or March. “In general, societies need to adjust sleep habits including length and timing to season, or adjust school and working schedules to seasonal sleep needs.”

Keyword: Biological Rhythms; Sleep
Link ID: 28672 - Posted: 02.18.2023

By Sheryl Gay Stolberg and Ellen Barry Lynn Rivers, a Democrat from Michigan, opened up about her diagnosis with bipolar disorder during a radio call-in show when she first ran for Congress. Her opponents had been hinting she had mental health problems. She decided, spur of the moment, to let it out. “Finally, I just said, ‘Are you asking me if I have depression? Yes, and so do thousands and millions of other people,’” she recalled. “I was like, ‘OK, here we go. The ball is thrown at you, just hit it.’ And so I did.” That was 1994. Ms. Rivers was elected, despite a Republican tidal wave, and served four terms. Now another Democrat, Senator John Fetterman of Pennsylvania, has announced that he has entered a hospital to be treated for clinical depression. Politicians of both parties are praising him for his openness. Mental health experts say he is a powerful symbol — especially for men, who are less likely to seek treatment for depression and suffer higher rates of suicide. Yet the stigma around mental illness remains strong — especially in politics, where questions about temperament can determine a candidate’s electability. Mr. Fetterman and others face a continuing challenge: How much do they really want to say? “We’ve come a long way; people are willing to say they have a diagnosis or that they’re going to therapy,” said Patrick J. Kennedy, a scion of the political Kennedy family, who disclosed his treatment for bipolar disorder and drug abuse when he was a congressman from Rhode Island. “But we’re still not in a place where people are comfortable saying any more than that. And really the question with Senator Fetterman is: How much is he going to disclose?” Clinical depression, also called major depression, is a severe form of the disease. Symptoms may include feelings of sadness, hopelessness or guilt; angry outbursts; loss of pleasure in ordinary activities; fatigue; anxiety; reduced appetite; and thoughts of suicide. In recent years, there have been great strides in treatment. © 2023 The New York Times Company

Keyword: Depression; Stroke
Link ID: 28671 - Posted: 02.18.2023

By Laura Sanders You’d be forgiven for thinking that depression has a simple explanation. The same mantra — that the mood disorder comes from a chemical imbalance in the brain — is repeated in doctors’ offices, medical textbooks and pharmaceutical advertisements. Those ads tell us that depression can be eased by tweaking the chemicals that are off-kilter in the brain. The only problem — and it’s a big one — is that this explanation isn’t true. The phrase “chemical imbalance” is too vague to be true or false; it doesn’t mean much of anything when it comes to the brain and all its complexity. Serotonin, the chemical messenger often tied to depression, is not the one key thing that explains depression. The same goes for other brain chemicals. The hard truth is that despite decades of sophisticated research, we still don’t understand what depression is. There are no clear descriptions of it, and no obvious signs of it in the brain or blood. The reasons we’re in this position are as complex as the disease itself. Commonly used measures of depression, created decades ago, neglect some important symptoms and overemphasize others, particularly among certain groups of people. Even if depression could be measured perfectly, the disorder exists amid myriad levels of complexity, from biological confluences of minuscule molecules in the brain all the way out to the influences of the world at large. Countless combinations of genetics, personality, history and life circumstances may all conspire to create the disorder in any one person. No wonder the science is stuck. So here, up front, is your fair warning: There will be no satisfying wrap-up at the end of this story. You will not come away with a scientific explanation for depression, because one does not exist. But there is a way forward for depression researchers, Aftab says. It requires grappling with nuances, complexity and imperfect data. © Society for Science & the Public 2000–2023.

Keyword: Depression
Link ID: 28670 - Posted: 02.15.2023

By Veronique Greenwood It is the rare person who likes hearing their own voice on a recording. It sounds fake, somehow — like it belongs to someone else. For neuroscientists, that quality of otherness is more than a curiosity. Many mysteries remain about the origins of hallucinations, but one hypothesis suggests that when people hear voices, they are hearing their own thoughts disguised as another person’s by a quirk of the brain. Scientists would like to understand what parts of the brain allow us to recognize ourselves speaking, but studying this using recordings of people’s own voices has proved tricky. When we talk, we not only hear our voice with our ears, but on some level we feel it as the sound vibrations travel through the bones of the skull. A study published Wednesday in the journal Royal Society Open Science attempted a workaround. A team of researchers investigated whether people could more accurately recognize their voices if they wore bone-conduction headphones, which transmit sound via vibration. They found that sending a recording through the facial bones made it easier for people to tell their voices apart from those of strangers, suggesting that this technology provides a better way to study how we can tell when we are speaking. That is a potentially important step in understanding the origins of hallucinated voices. Recordings of our voices tend to sound higher than we expect, said Pavo Orepic, a postdoctoral researcher at the Swiss Federal Institute of Technology who led the study. The vibration of the skull makes your voice sound deeper to yourself than to a listener. But even adjusting recordings so they sound lower doesn’t recreate the experience of hearing your own voice. As an alternative, the team tried using bone-conduction headphones, which are commercially available and often rest on a listener’s cheekbones just in front of the ear. © 2023 The New York Times Company

Keyword: Schizophrenia; Hearing
Link ID: 28669 - Posted: 02.15.2023

By Allison Whitten The neocortex stands out as a stunning achievement of biological evolution. All mammals have this swath of tissue covering their brain, and the six layers of densely packed neurons within it handle the sophisticated computations and associations that produce cognitive prowess. Since no animals other than mammals have a neocortex, scientists have wondered how such a complex brain region evolved. The brains of reptiles seemed to offer a clue. Not only are reptiles the closest living relatives of mammals, but their brains have a three-layered structure called a dorsal ventricular ridge, or DVR, with functional similarities to the neocortex. For more than 50 years, some evolutionary neuroscientists have argued that the neocortex and the DVR were both derived from a more primitive feature in an ancestor shared by mammals and reptiles. Now, however, by analyzing molecular details invisible to the human eye, scientists have refuted that view. By looking at patterns of gene expression in individual brain cells, researchers at Columbia University showed that despite the anatomical similarities, the neocortex in mammals and the DVR in reptiles are unrelated. Instead, mammals seem to have evolved the neocortex as an entirely new brain region, one built without a trace of what came before it. The neocortex is composed of new types of neurons that seem to have no precedent in ancestral animals. The paper describing this work, which was led by the evolutionary and developmental biologist Maria Antonietta Tosches, was published last September in Science. This process of evolutionary innovation in the brain isn’t limited to the creation of new parts. Other work by Tosches and her colleagues in the same issue of Science showed that even seemingly ancient brain regions are continuing to evolve by getting rewired with new types of cells. The discovery that gene expression can reveal these kinds of important distinctions between neurons is also prompting researchers to rethink how they define some brain regions and to reassess whether some animals might have more complex brains than they thought. All Rights Reserved © 2023

Keyword: Development of the Brain; Evolution
Link ID: 28668 - Posted: 02.15.2023

By Stephani Sutherland Tara Ghormley has always been an overachiever. She finished at the top of her class in high school, graduated summa cum laude from college and earned top honors in veterinary school. She went on to complete a rigorous training program and build a successful career as a veterinary internal medicine specialist. But in March 2020 she got infected with the SARS-CoV-2 virus—just the 24th case in the small, coastal central California town she lived in at the time, near the site of an early outbreak in the COVID pandemic. “I could have done without being first at this,” she says. Almost three years after apparently clearing the virus from her body, Ghormley is still suffering. She gets exhausted quickly, her heartbeat suddenly races, and she goes through periods where she can't concentrate or think clearly. Ghormley and her husband, who have relocated to a Los Angeles suburb, once spent their free time visiting their “happiest place on Earth”—Disneyland—but her health prevented that for more than a year. She still spends most of her days off resting in the dark or going to her many doctors' appointments. Her early infection and ongoing symptoms make her one of the first people in the country with “long COVID,” a condition where symptoms persist for at least three months after the infection and can last for years. The syndrome is known by medical professionals as postacute sequelae of COVID-19, or PASC. People with long COVID have symptoms such as pain, extreme fatigue and “brain fog,” or difficulty concentrating or remembering things. As of February 2022, the syndrome was estimated to affect about 16 million adults in the U.S. and had forced between two million and four million Americans out of the workforce, many of whom have yet to return. Long COVID often arises in otherwise healthy young people, and it can follow even a mild initial infection. The risk appears at least slightly higher in people who were hospitalized for COVID and in older adults (who end up in the hospital more often). Women and those at socioeconomic disadvantage also face higher risk, as do people who smoke, are obese, or have any of an array of health conditions, particularly autoimmune disease. Vaccination appears to reduce the danger but does not entirely prevent long COVID.

Keyword: Attention; Learning & Memory
Link ID: 28667 - Posted: 02.15.2023

By Ted Alcorn Ever wake up regretting the last round of drinks from the previous night? There’s a medicine that might help. A recent study adds to the evidence that people who binge-drink may benefit from taking a dose of the medication naltrexone before consuming alcohol, a finding that may be welcomed now that alcohol-related deaths in the United States have surpassed 140,000 a year. Nearly half of American drinkers reported bingeing, defined as more than four drinks in a sitting for men and more than three for women, in the previous month, according to a U.S. government health survey. Some may view binge-drinking as harmless because the habit is widespread and a low percentage of binge drinkers are dependent on alcohol, according to experts. But it is considered a major risk factor for alcohol-related illness and injuries, and it heightens the possibility that an individual will develop an alcohol disorder. In the study, which was published in December in the American Journal of Psychiatry, 120 men who wanted to reduce bingeing but were not severely dependent on alcohol were given naltrexone to take whenever they felt a craving for alcohol or anticipated a period of heavy drinking. Naltrexone, which blocks endorphins and reduces the euphoria of intoxication, was approved in the United States for the treatment of alcohol dependence nearly 30 years ago. But it is typically prescribed for patients with more severe alcohol disorders to take daily to abstain from drinking. The new study’s targeted approach, in which patients were advised to take the pill one hour before they expected to drink, is less common, although studies going back decades have also demonstrated the effectiveness of the as-needed dosing method. © 2023 The New York Times Company

Keyword: Drug Abuse
Link ID: 28666 - Posted: 02.15.2023

Jon Hamilton When Tom's epileptic seizures could no longer be controlled with drugs, he started considering surgery. Tom – who asked that we not use his last name because he worries that employers might be alarmed by his medical history – was hoping doctors could remove the faulty brain tissue that sometimes caused him to convulse and lose consciousness. He underwent a grueling evaluation at the epilepsy center at the University of California, San Diego. Doctors removed a piece of his skull and placed electrodes on the surface of his brain. He spent a week in the hospital while doctors watched him having seizures. Then, he got bad news. "You're not an optimal surgery patient," he recalled the doctors telling him." We don't feel safe operating on you." That was in 2009. In 2018, with epilepsy taking a heavy toll on his work and family life, Tom went back to his doctors at UCSD to discuss treatment options. This time he met with Dr. Jerry Shih, the center's director. "I told him, you know what, we're in a unique situation now where we have some of the newer technologies that were not available" in 2009, Shih says. This time, the team inserted tiny electrodes into Tom's brain to find the primary source of his seizures. Then, in 2019, they used a laser to remove that bit of his brain. © 2023 npr

Keyword: Epilepsy
Link ID: 28665 - Posted: 02.15.2023

By Erin Garcia de Jesús A female giraffe has a great Valentine’s Day gift for potential mates: urine. Distinctive anatomy helps male giraffes get a taste for whether a female is ready to mate, animal behaviorists Lynette and Benjamin Hart report January 19 in Animals. A pheromone-detecting organ in giraffes has a stronger connection to the mouth than the nose, the researchers found. That’s why males scope out which females to mate with by sticking their tongues in a urine stream. Animals such as male gazelles will lick fresh urine on the ground to track if females are ready to mate. But giraffes’ long necks and heavy heads make bending over to investigate urine on the ground an unstable and vulnerable position, says Lynette Hart, of the University of California, Davis. The researchers observed giraffes (Giraffa giraffa angolensis) in Etosha National Park in Namibia in 1994, 2002 and 2004. Bull giraffes nudged or kicked the female to ask her to pee. If she was a willing participant, she urinated for a few seconds, while the male took a sip. Then the male curled his lip and inhaled with his mouth, a behavior called a flehmen response, to pull the female’s scent into two openings on the roof of the mouth. From the mouth, the scent travels to the vomeronasal organ, or VNO, which detects pheromones. The Harts say they never saw a giraffe investigate urine on the ground. Unlike many other mammals, giraffes have a stronger oral connection — via a duct — to the VNO, than a nasal one, examinations of preserved giraffe specimens showed. One possible explanation for the difference could be that a VNO-nose link helps animals that breed at specific times of the year detect seasonal plants, says Benjamin Hart, a veterinarian also at the University of California, Davis. But giraffes can mate any time of year, so the nasal connection may not matter as much. © Society for Science & the Public 2000–2023.

Keyword: Chemical Senses (Smell & Taste); Sexual Behavior
Link ID: 28664 - Posted: 02.15.2023

By Erin Garcia de Jesús Forget screwdrivers or drills. A stick and a straw make for a great cockatoo tool kit. Some Goffin’s cockatoos (Cacatua goffiniana) know whether they need to have more than one tool in claw to topple an out-of-reach cashew, researchers report February 10 in Current Biology. By recognizing that two items are necessary to access the snack, the birds join chimpanzees as the only nonhuman animals known to use tools as a set. The study is a fascinating example of what cockatoos are capable of, says Anne Clark, a behavioral ecologist at Binghamton University in New York, who was not involved in the study. A mental awareness that people often attribute to our close primate relatives can also pop up elsewhere in the animal kingdom. A variety of animals including crows and otters use tools but don’t deploy multiple objects together as a kit (SN: 9/14/16; SN: 3/21/17). Chimpanzees from the Republic of Congo’s Noubalé-Ndoki National Park, on the other hand, recognize the need for both a sharp stick to break into termite mounds and a fishing stick to scoop up an insect feast (SN: 10/19/04). Researchers knew wild cockatoos could use three different sticks to break open fruit in their native range of Indonesia. But it was unclear whether the birds might recognize the sticks as a set or instead as a chain of single tools that became necessary as new problems arose, says evolutionary biologist Antonio Osuna Mascaró of the University of Veterinary Medicine Vienna. © Society for Science & the Public 2000–2023.

Keyword: Learning & Memory; Evolution
Link ID: 28663 - Posted: 02.11.2023

By Elizabeth Preston A fully grown male orca is one of the planet’s fiercest hunters. He’s a wily, streamlined torpedo who can weigh as much as 11 tons. No other animal preys on him. Yet in at least one population, these apex predators struggle to survive without their moms, who catch their food and even cut it up for them. Scientists have previously seen that some killer whale mothers share food with their grown sons. In a study published Wednesday in Current Biology, researchers found that this prolonged feeding carries a huge reproductive cost for mothers. Killer whales, actually the largest members of the dolphin family, swim throughout the world’s oceans. Yet they live in discrete populations with their own territories, dialects and hunting customs. A group that spends much of the year off the coast of British Columbia, Washington and Oregon is known as the southern residents. They eat mainly Chinook salmon, which have been increasingly hard to find. “Killer whales worldwide are doing fine,” said Michael Weiss, research director at the Center for Whale Research in Friday Harbor, Wash. But the southern residents, with a population of just 73, are considered endangered. These whales stay with their birth family for their whole lives. The families are led by matriarchs who can live 80 to 90 years. Yet the females stop reproducing in midlife: Orcas and a few other whale species are the only mammals, besides humans, known to undergo menopause. To try to explain menopause, scientists have looked for ways that matriarchs encourage the survival of their children and grandchildren. A 2012 study of southern resident killer whales, along with their neighbors, the northern residents, showed that the presence of older moms helped adult offspring stay alive — especially sons. Males over age 30 were eight times more likely to die in the year following their own mothers’ deaths. © 2023 The New York Times Company

Keyword: Sexual Behavior; Evolution
Link ID: 28662 - Posted: 02.11.2023

By Erin Blakemore Tinnitus — a ringing or whistling sound in the ears — plagues millions worldwide. Though the estimates of those bothered by the condition vary, a new study suggests they may have something in common: exposure to road traffic noise at home. The paper, published in Environmental Health Perspectives, looked to Denmark to find a potential link between road noise and tinnitus levels. The nationwide study included data on 3.5 million Danish residents who were 30 and older between 2000 and 2017. Over that time, 40,692 were diagnosed with tinnitus. When the researchers calculated likely traffic and noise levels at the quietest facade of their residences in that period, they found those living with louder road noise were more likely to be diagnosed with tinnitus than those who lived in quieter areas. People’s risk rose 6 percent with every 10-decibel increase in road traffic noise compared with controls. Levels rose the longer a person had been exposed to higher road traffic noise. Women, people without a previous history of hearing loss, and people with higher education and income were at increased risk. The study did not find an association between railway noise and tinnitus diagnoses. Though the paper shows an association between tinnitus and traffic noise, it does not prove that one causes the other. The researchers say it’s important to learn more about the potential effects of residential noise exposure — and posit that if traffic noise does cause tinnitus, it might do so by disrupting people’s sleep. “We know that traffic noise can make us stressed and affect our sleep. And that tinnitus can get worse when we live under stressful situations and we do not sleep well,” said Jesper Hvass Schmidt, an associate professor at the University of Southern Denmark and the paper’s co-author, in a news release.

Keyword: Hearing
Link ID: 28661 - Posted: 02.11.2023

ByRachel Zamzow A long-smoldering debate among scientists studying autism has erupted. At issue is language—for example, whether researchers should describe autism as a “disorder,” “disability,” or “difference,” and whether its associated features should be called “symptoms” or simply “traits.” In scientific papers and commentaries published in recent months, some have decried ableist language among their colleagues whereas others have defended traditional terminology—with both sides saying they have the best interests of autistic people in mind. The vitriol is harming the field and silencing researchers, some fear, but others see it as a long-overdue reckoning. Since autism’s earliest descriptions in the academic literature as a condition affecting social interaction and communication, researchers and clinicians have framed it as a medical disorder, with a set of symptoms to be treated. Historically, autistic children have been institutionalized and subjected to treatments involving physical punishment, food restriction, and electric shocks. Even today, the most widely used autism therapy—applied behavior analysis—is seen by some as a harmful tool of normalization. Many autistic people and their families have instead embraced the view that their difficulties lie not with their autism, but with a society that isn’t built to support them. But according to some autism researchers, the field still too often defaults to terms with negative connotations. For example, in addition to “symptom” and “disorder,” many scientists use the term “comorbid” rather than the more neutral “co-occurring” to describe conditions that tend to accompany autism. Similarly, some argue the oft-used phrase “people with autism,” as opposed to “autistic person,” can imply that autism is necessarily an unwanted harmful condition. In a recent survey of 195 autism researchers, 60% of responses included views about autistic people the study authors deemed dehumanizing, objectifying, or stigmatizing. Some responses described autistic people as “shut down from the outside world” or “completely inexpressive and apparently without emotions,” according to the November 2022 Frontiers in Psychology study. “What is worse than I thought was how blatant a lot of the content was, which shows that, for [a] large proportion of participants, they did not consider the things they were saying to be problematic at all,” says lead author Monique Botha, a psychologist at the University of Stirling.

Keyword: Autism
Link ID: 28660 - Posted: 02.08.2023

By Betsy Mason Some fish can recognize their own faces in photos and mirrors, an ability usually attributed to humans and other animals considered particularly brainy, such as chimpanzees, scientists report. Finding the ability in fish suggests that self-awareness may be far more widespread among animals than scientists once thought. “It is believed widely that the animals that have larger brains will be more intelligent than animals of the small brain,” such as fish, says animal sociologist Masanori Kohda of Osaka Metropolitan University in Japan. It may be time to rethink that assumption, Kohda says. Kohda’s previous research showed that bluestreak cleaner wrasses can pass the mirror test, a controversial cognitive assessment that purportedly reveals self-awareness, or the ability to be the object of one’s own thoughts. The test involves exposing an animal to a mirror and then surreptitiously putting a mark on the animal’s face or body to see if they will notice it on their reflection and try to touch it on their body. Previously only a handful of large-brained species, including chimpanzees and other great apes, dolphins, elephants and magpies, have passed the test. In a new study, cleaner fish that passed the mirror test were then able to distinguish their own faces from those of other cleaner fish in still photographs. This suggests that the fish identify themselves the same way humans are thought to — by forming a mental image of one’s face, Kohda and colleagues report February 6 in the Proceedings of the National Academy of Sciences. “I think it’s truly remarkable that they can do this,” says primatologist Frans de Waal of Emory University in Atlanta who was not involved in the research. “I think it’s an incredible study.” © Society for Science & the Public 2000–2023.

Keyword: Attention; Evolution
Link ID: 28659 - Posted: 02.08.2023

By Susan Dominus For the past two or three years, many of my friends, women mostly in their early 50s, have found themselves in an unexpected state of suffering. The cause of their suffering was something they had in common, but that did not make it easier for them to figure out what to do about it, even though they knew it was coming: It was menopause. The symptoms they experienced were varied and intrusive. Some lost hours of sleep every night, disruptions that chipped away at their mood, their energy, the vast resources of good will that it takes to parent and to partner. One friend endured weeklong stretches of menstrual bleeding so heavy that she had to miss work. Another friend was plagued by as many as 10 hot flashes a day; a third was so troubled by her flights of anger, their intensity new to her, that she sat her 12-year-old son down to explain that she was not feeling right — that there was this thing called menopause and that she was going through it. Another felt a pervasive dryness in her skin, her nails, her throat, even her eyes — as if she were slowly calcifying. Then last year, I reached the same state of transition. Technically, it is known as perimenopause, the biologically chaotic phase leading up to a woman’s last period, when her reproductive cycle makes its final, faltering runs. The shift, which lasts, on average, four years, typically starts when women reach their late 40s, the point at which the egg-producing sacs of the ovaries start to plummet in number. In response, some hormones — among them estrogen and progesterone — spike and dip erratically, their usual signaling systems failing. During this time, a woman’s period may be much heavier or lighter than usual. As levels of estrogen, a crucial chemical messenger, trend downward, women are at higher risk for severe depressive symptoms. Bone loss accelerates. In women who have a genetic risk for Alzheimer’s disease, the first plaques are thought to form in the brain during this period. Women often gain weight quickly, or see it shift to their middles, as the body fights to hold onto the estrogen that abdominal fat cells produce. The body is in a temporary state of adjustment, even reinvention, like a machine that once ran on gas trying to adjust to solar power, challenged to find workarounds. © 2023 The New York Times Company

Keyword: Hormones & Behavior; Sexual Behavior
Link ID: 28658 - Posted: 02.08.2023

by Peter Hess An autism-linked mutation in the gene CHD8 yields wildly different physical and behavioral traits in mice depending on their genetic backgrounds, according to a study of 33 mouse strains. The findings were published today in Neuron. The results serve as a stark reminder that traits associated with an autism-linked mutation reflect more than just that mutation, says senior investigator Pat Levitt, chair of developmental neurogenetics at Children’s Hospital Los Angeles in California. Differences in genetic background could also explain why some findings from autism model mice have failed to replicate across labs, he adds. People with CHD8 mutations often have autism, intellectual disability, gastrointestinal issues and macrocephaly — larger-than-average head size — but not all of them have all of these traits. This variability may stem from interactions between the mutations and other variants across the genome, says study investigator Manal Tabbaa, a postdoctoral research fellow in Levitt’s lab. The new work does not reveal how the same CHD8 mutation can affect different mice — or people — differently. But researchers could use the genetically diverse rodents to answer this question, and to better understand and model autism’s heterogeneity, Tabbaa and Levitt say. “This is such a comprehensive approach to understand a really clinically relevant question, and it’s almost unbelievable that just three people could do this amount of work, considering how much it looks like was done,” says Joseph Gleeson, professor of neurosciences at the University of California, San Diego, who was not involved in the study. “They are just scratching the surface of what could be really fantastic future efforts.” © 2023 Simons Foundation

Keyword: Autism; Genes & Behavior
Link ID: 28657 - Posted: 02.08.2023

ByKatherine Kornei In the summer of 2021, a 54-year-old man was brought to a hospital in Northern California after an unexplained seizure. When an MRI revealed a mysterious mass in the left side of his brain, he was transferred to the University of California, San Francisco (UCSF), Medical Center. A brain biopsy and other tests revealed not a tumor, but an incredibly rare infection of the central nervous system caused by the amoeba Balamuthia mandrillaris. One of several “brain-eating” amoebae that occasionally spark headlines, the pathogen kills more than 90% of people who contract it. But despite initial setbacks, the patient survived and has largely recovered after experimental treatment with a decades-old drug. As his UCSF medical team recounted in a paper last month, a desperate hunt for a cure led them to a study published several years ago in which researchers showed a drug originally developed in Europe to quell urinary tract infections was effective against Balamuthia in the laboratory. That discovery sent the medical team rushing to obtain the drug, nitroxoline, from abroad so it could be given for the first time to a Balamuthia patient. Researchers not involved with the case call the man’s recovery a breakthrough in treating a brain infection that’s long been presumed to be a death sentence. “It’s the best that I ever remember seeing with Balamuthia,” says Dennis Kyle, a cell biologist at the University of Georgia, Athens, who studies amoebic diseases. The drug, which is not approved for regular use in the United States, has also been effective against other pathogenic amoebae in laboratory tests, according to the UCSF team. Balamuthia mandrillaris was first identified in 1986—not in a hospital but at the San Diego Wild Animal Park, where staff were eagerly anticipating the birth of a mandrill, the largest species of monkey. But one day, Nyani, the mother-to-be, began dragging her right arm on the ground. Within 48 hours she became lethargic, and she eventually stopped moving and died. A postmortem evaluation of Nyani’s brain tissue revealed hemorrhaging and centimeter-scale lesions. The culprits were plainly visible: Amoebae were eating Nyani’s brain.

Keyword: Miscellaneous
Link ID: 28656 - Posted: 02.04.2023

By McKenzie Prillaman A newfound species of frog doesn’t ribbit. In fact, it doesn’t make any sound at all. Many frogs have unusual characteristics, from turning translucent to being clumsy jumpers (SN: 12/22/22; 6/15/22). The recently discovered amphibian lacks a voice. It joins a group of seven other voiceless frog species called spiny-throated reed frogs that reside in East Africa. Instead of croaking, the spines on male frogs’ throats might help their female counterparts recognize potential mates via touch, sort of like braille, says conservation biologist Lucinda Lawson of the University of Cincinnati. Lawson and colleagues spotted the little frog, only about 25 millimeters long, in 2019 while surveying wildlife in Tanzania’s Ukaguru Mountains. The team immediately recognized the animal, now named Hyperolius ukaguruensis, as a spiny-throated reed frog. But something seemed off. “It [was] the wrong color,” Lawson says. Most frogs from this group are green and silver, but this one was gold and brown. Some quick measurements to check if the peculiar frog simply had trivial color variations or if it could be a new species revealed that its eyes were smaller than other spiny-throated reed frogs. The researchers agreed: “Let’s do some genetics,” Lawson says. They ran DNA tests on two frogs that looked like they belonged to the suspected new species, as well as 10 individuals belonging to known spiny-throated species. Comparing the golden frogs’ genetic makeup with that of the others revealed the oddballs were genetically distinct, Lawson and colleagues report February 2 in PLOS ONE. © Society for Science & the Public 2000–2023.

Keyword: Animal Communication; Sexual Behavior
Link ID: 28655 - Posted: 02.04.2023