By Gina Kolata Are you a man worried about your testosterone levels? Hoping to give them a boost? Tucker Carlson, the Fox News host, has a solution. A promotional video for a new installment in a video series by Mr. Carlson describes a “total collapse of testosterone levels in American men,” positing an explanation for what he and many conservatives see as a creeping loss of masculinity in today’s society. Chock-full of oiled, shirtless men performing vaguely masculine tasks, like turning over giant tires and throwing a javelin, the video has already been widely remarked upon on social media for its bizarre erotic imagery. But one shot in particular stands out: a naked man atop a rock pile, limbs outflung, exposing his genitals to the red light issuing from what appears to be a waist-high air purifier. Something very like the theme from “2001: A Space Odyssey” plays in the background. This is the treatment proposed by Mr. Carlson’s “documentary”: Revive your underperforming testicles with red light, in particular a device made by a little known company called Joovv. A leading endocrinologist says — no surprise — the whole thing is ridiculous, and not just because of the man receiving light therapy atop a pile of stone slabs in the dead of night. First, there is precious little evidence that testosterone “levels are declining by roughly 10 percent per decade, completely changing the way people are at the most fundamental level,” as Mr. Carlson has said. Studies examining changes in testosterone over time are challenging for several reasons, including difficulties in recruiting large populations of normal subjects, daily circadian changes in testosterone, and differences in testing methods over time, noted Dr. John Amory, an expert on male reproductive health at the University of Washington. © 2022 The New York Times Company

Keyword: Hormones & Behavior; Sexual Behavior
Link ID: 28298 - Posted: 04.23.2022

By Brittany Shammas and Timothy Bella William Husel, an Ohio doctor who was accused of killing 14 patients with what prosecutors described as “wildly excessive” doses of fentanyl between 2015 and 2018, was acquitted on all counts of murder Wednesday, concluding one of the most significant murder cases of its kind against a health-care professional. Husel, a onetime physician of the year trained at the Cleveland Clinic, faced one count of murder for each of the 14 critically ill patients he was accused of killing. The jury deliberated for seven days before finding him not guilty on all 14 counts in what was one of the largest murder trials in Ohio history. He had been charged with causing or hastening their deaths amid a period of lax oversight of fentanyl at Mount Carmel West, a Catholic hospital in Columbus. Husel would have faced life in prison with just one guilty verdict. While the synthetic opioid is significantly more powerful than morphine and has wreaked havoc on American streets, it can provide pain relief in medical settings that is crucial to end-of-life care. The alleged victims in the Ohio case suffered critical medical conditions including overdoses, cancer, strokes and internal bleeding. Prosecutors acknowledged that all were being kept alive on ventilators and that many of them were dying. “In truth, William Husel was an innocent man, and thank goodness the justice system prevailed,” Jose Baez, one of Husel’s defense attorneys, told reporters. The 46-year-old’s acquittal came after a two-month trial that triggered a debate on end-of-life medical care. Husel and Baez argued in the trial that the doctor offered comfort care for dying patients and was not trying to kill them. They pointed out that the doctor’s actions did not occur in secret — nurses were the ones to administer the doses — and alleged that hospital officials made Husel the villain after realizing the systemic failures at play. The fallout over the allegations at Mount Carmel West had repercussions: the firing of 23 employees; the resignation of the hospital’s chief executive, chief clinical officer and chief pharmacy officer; and Medicare and Medicaid funding for the institution was put in jeopardy. © 1996-2022 The Washington Post

Keyword: Pain & Touch; Drug Abuse
Link ID: 28297 - Posted: 04.23.2022

By Katharine Q. Seelye Ursula Bellugi, a pioneer in the study of the biological foundations of language who was among the first to demonstrate that sign language was just as complex, abstract and systematic as spoken language, died on Sunday in San Diego. She was 91. Her death, at an assisted living facility, was confirmed by her son Rob Klima. Dr. Bellugi was a leading researcher at the Salk Institute for Biological Studies in San Diego for nearly five decades and, for much of that time, was director of its laboratory for cognitive neuroscience. She made significant contributions in three main areas: the development of language in children; the linguistic structure and neurological basis of American Sign Language; and the social behavior and language abilities of people with a rare genetic disorder, Williams syndrome. “She leaves an indelible legacy of shedding light on how humans communicate and socialize with each other,” Rusty Gage, president of the Salk Institute, said in a statement. Dr. Bellugi’s work, much of it done in collaboration with her husband, Edward S. Klima, advanced understanding of the brain and the origins of language, both signed and spoken. American Sign Language was first described as a true language in 1960 by William C. Stokoe Jr., a professor at Gallaudet University, the world’s only liberal arts university devoted to deaf people. But he was ridiculed and attacked for that claim. Dr. Bellugi and Dr. Klima, who died in 2008, demonstrated conclusively that the world’s signed languages — of which there are more than 100 — were actual languages in their own right, not just translations of spoken languages. Dr. Bellugi, who focused on American Sign Language, established that these linguistic systems were passed down, in all their complexity, from one generation of deaf people to the next. For that reason, the scientific community regards her as the founder of the neurobiology of American Sign Language. The couple’s work led to a major discovery at the Salk lab: that the left hemisphere of the brain has an innate predisposition for language, whether spoken or signed. That finding gave scientists fresh insight into how the brain learns, interprets and forgets language. © 2022 The New York Times Company

Keyword: Language; Laterality
Link ID: 28296 - Posted: 04.23.2022

Grace Browne In early February 2016, after reading an article featuring a couple of scientists at the Massachusetts Institute of Technology who were studying how the brain reacts to music, a woman felt inclined to email them. “I have an interesting brain,” she told them. EG, who has requested to go by her initials to protect her privacy, is missing her left temporal lobe, a part of the brain thought to be involved in language processing. EG, however, wasn’t quite the right fit for what the scientists were studying, so they referred her to Evelina Fedorenko, a cognitive neuroscientist, also at MIT, who studies language. It was the beginning of a fruitful relationship. The first paper based on EG’s brain was recently published in the journal Neuropsychologia, and Fedorenko’s team expects to publish several more. For EG, who is in her fifties and grew up in Connecticut, missing a large chunk of her brain has had surprisingly little effect on her life. She has a graduate degree, has enjoyed an impressive career, and speaks Russian—a second language–so well that she has dreamed in it. She first learned her brain was atypical in the autumn of 1987, at George Washington University Hospital, when she had it scanned for an unrelated reason. The cause was likely a stroke that happened when she was a baby; today, there is only cerebro-spinal fluid in that brain area. For the first decade after she found out, EG didn't tell anyone other than her parents and her two closest friends. “It creeped me out,” she says. Since then, she has told more people, but it's still a very small circle that is aware of her unique brain anatomy. © Condé Nast Britain 2022.

Keyword: Development of the Brain; Language
Link ID: 28295 - Posted: 04.20.2022

By Kim Tingley In March, neuroscientists and psychiatrists from the School of Medicine at Washington University, St. Louis, along with colleagues elsewhere, published a study in the journal Nature that sparked widespread discussion in their fields. Researchers, the study noted, are increasingly using magnetic resonance imaging — which can reveal the brain’s structure and activity — to try to find links between what is seen on an M.R.I., like cortical thickness or patterns of connection, and complicated psychological traits, like cognitive ability or mental-health conditions. In theory, such so-called brain-wide association studies could yield incredibly valuable insights. Knowing that a particular neurological feature makes someone more vulnerable to autism, Alzheimer’s or another disorder, for example, could help predict, prevent or treat that condition. Likewise, if we can link certain features to desirable traits, like academic achievement, it might be possible to take advantage of that knowledge. The problem, the Nature authors argued, is that neuroscientists often are searching for those associations in groups of study subjects that are too small, leading to results that are statistically “underpowered.” In general, they calculated, thousands of subjects should be included for a brain-wide association study to produce a finding that other studies can replicate. This was unwelcome news to many, in large part because M.R.I. machines are incredibly expensive to use, often at about $1,000 per hour, and funding is limited. Specific instances of underpowered studies are legion. So much so, says Terry Jernigan, director of the Center for Human Development at the University of California, San Diego, that singling out an example “would simply be unfair.” Indeed, according to a paper from 2020 in NeuroImage, the average number of study subjects in more than a thousand of the most cited brain-imaging papers, published between 1990 and 2012, was 12; the Nature paper calculated that the median sample size for neuroimaging studies uploaded to a popular open-access platform as of September 2021 was 23. © 2022 The New York Times Company

Keyword: Brain imaging
Link ID: 28294 - Posted: 04.20.2022

pmByElizabeth Pennisi With more microbes than cells in our body, it’s not surprising that bacteria and other invisible “guests” influence our metabolism, immune system, and even our behavior. Now, researchers studying mice have worked out how bacteria in the mammalian gut can ping the brain to regulate an animal’s appetite and body temperature—and it involves the same molecular pathway the immune system uses to detect bacterial pathogens. “It’s quite an important finding,” says Antoine Adamantidis, a neuroscientist at the University of Bern who was not involved with the work. “Our life depends on food intake, and this is one more [thing] that bacteria can [influence].” Over the past 20 years, researchers have uncovered connections between the human gut and the rest of the body. They have linked certain intestinal microbes to conditions such as depression, multiple sclerosis, and immune system disorders; they have also documented nervous system connections between the gut and the brain. But researchers have been hard pressed to understand exactly how gut microbes—or the molecules they make—influence the brain. When certain gut bacteria infiltrate the rest of the body, our immune system picks up on them by sensing fragments of their cell walls, known as muropeptides. Our molecular detectors for these muropeptides, proteins called Nod2, coat the surfaces of cells involved in the body’s first line of defense. Ilana Gabanyi, a neuroimmunologist at the Pasteur Institute, wanted to know whether these molecular detectors also exist in the brain’s nerve cells. © 2022 American Association for the Advancement of Science.

Keyword: Obesity
Link ID: 28293 - Posted: 04.20.2022

Liam Drew James Johnson hopes to drive a car again one day. If he does, he will do it using only his thoughts. In March 2017, Johnson broke his neck in a go-carting accident, leaving him almost completely paralysed below the shoulders. He understood his new reality better than most. For decades, he had been a carer for people with paralysis. “There was a deep depression,” he says. “I thought that when this happened to me there was nothing — nothing that I could do or give.” But then Johnson’s rehabilitation team introduced him to researchers from the nearby California Institute of Technology (Caltech) in Pasadena, who invited him to join a clinical trial of a brain–computer interface (BCI). This would first entail neurosurgery to implant two grids of electrodes into his cortex. These electrodes would record neurons in his brain as they fire, and the researchers would use algorithms to decode his thoughts and intentions. The system would then use Johnson’s brain activity to operate computer applications or to move a prosthetic device. All told, it would take years and require hundreds of intensive training sessions. “I really didn’t hesitate,” says Johnson. The first time he used his BCI, implanted in November 2018, Johnson moved a cursor around a computer screen. “It felt like The Matrix,” he says. “We hooked up to the computer, and lo and behold I was able to move the cursor just by thinking.” Johnson has since used the BCI to control a robotic arm, use Photoshop software, play ‘shoot-’em-up’ video games, and now to drive a simulated car through a virtual environment, changing speed, steering and reacting to hazards. “I am always stunned at what we are able to do,” he says, “and it’s frigging awesome.” © 2022 Springer Nature Limited

Keyword: Brain imaging; Robotics
Link ID: 28292 - Posted: 04.20.2022

Rachel Zamzow Andrew Whitehouse never expected his work as an autism researcher to put him in danger. But that’s exactly what happened soon after he and his colleagues reported in 2020 that few autism interventions used in the clinic are backed by solid evidence. Within weeks, a range of clinicians, therapy providers and professional organizations had threatened to sue Whitehouse or had issued complaints about him to his employer. Some harassed his family, too, putting their safety at risk, he says. For Whitehouse, professor of autism research at the Telethon Kids Institute and the University of Western Australia in Perth, the experience came as a shock. “It’s so absurd that just a true and faithful reading of science leads to this,” he says. “It’s an untold story.” In fact, Whitehouse’s findings were not outliers. Another 2020 study—the Autism Intervention Meta-Analysis, or Project AIM for short—plus a string of reviews over the past decade also highlight the lack of evidence for most forms of autism therapy. Yet clinical guidelines and funding organizations have continued to emphasize the efficacy of practices such as applied behavior analysis (ABA). And early intervention remains a near-universal recommendation for autistic children at diagnosis. The field urgently needs to reassess those claims and guidelines, says Kristen Bottema-Beutel, associate professor of special education at Boston College in Massachusetts, who worked on Project AIM. “We need to understand that our threshold of evidence for declaring something evidence-based is rock-bottom low,” she says. “It is very unlikely that those practices actually produce the changes that we’re telling people they do.” © 1986–2022 The Scientist.

Keyword: Autism
Link ID: 28291 - Posted: 04.20.2022

By Apoorva Mandavilli A small biotech company that trumpeted an exciting new treatment for Alzheimer’s disease is now under fire for irregularities in its research results, after several studies related to its work were retracted or questioned by scientific journals. The company, Cassava Sciences, based in Austin, Texas, announced last summer that its drug, simufilam, improved cognition in Alzheimer’s patients in a small clinical trial, describing it as the first such advance in treatment of the disease. Cassava later initiated a larger trial. The drug’s potential garnered enormous attention from investors. Alzheimer’s disease affects roughly six million Americans, a number that is expected to double by 2050, and an effective treatment would be lucrative. Cassava’s stock soared, by more than 1,500 percent at one point. The company was worth nearly $5 billion last summer. But many scientists have been deeply skeptical of the company’s claims, asserting that Cassava’s studies were flawed, its methods opaque and its results improbable. Families of some trial participants have said they see improvements. But critics noted that the trial reporting better cognition due to simufilam lacked a placebo group, and asserted that the Alzheimer’s patients were not followed long enough to confirm that any improvements in cognition were genuine. Some experts went further, accusing the company of manipulating its scientific results. In response to the allegations, in December The Journal of Neuroscience published “expressions of concern” regarding two brain studies authored by the company’s chief collaborator, Hoau-Yan Wang, a professor at the City University of New York. One was co-written by Lindsay H. Burns, chief scientist at Cassava. The journal editors also noted errors in the images accompanying the latter study. (An “expression of concern” indicates that the editors have reason to question the integrity and accuracy of a paper.) © 2022 The New York Times Company

Keyword: Alzheimers
Link ID: 28290 - Posted: 04.20.2022

Diana Kwon Susannah Cahalan was 24 years old when her world turned upside down. Cahalan was living a busy life as a news reporter at the New York Post when she suddenly began experiencing sensitivity to light, numbness in her limbs, and an unsettling feeling that something was not quite right in her body and her brain. One day at work, she found herself inexplicably going from crying hysterically to skipping giddily down a hall. After a seizure landed her in the hospital, her condition rapidly worsened. She started having delusions and hallucinations, believing that her father was a murderer, that she was being secretly recorded, and that she could age people using her mind. In a matter of weeks, walking, speaking, and swallowing became difficult. She eventually became immobile and unresponsive, lying in her hospital bed in a catatonic state. Despite her worsening condition, dozens of specialists from various fields—psychiatry, neurology, internal medicine—couldn’t figure out what was wrong. Numerous blood tests and brain scans failed to generate answers. To many who saw her, Cahalan’s condition looked indistinguishable from mental illnesses such as bipolar disorder or schizophrenia, in which people can experience delusions and hallucinations that make it difficult for them to distinguish what’s real and what’s not. It wasn’t until a neurologist asked Cahalan to draw a clock that the problem became clear. Cahalan had drawn all the numbers on just one side of the clock face, indicating that there was a problem in the functioning of one half of her brain. A brain biopsy confirmed what the doctor had suspected. Cahalan had anti-NMDAR encephalitis, a rare autoimmune disease in which the body produces antibodies that attack the NMDA receptor, a protein found throughout the brain. The condition had only been discovered in the early 2000s, just a few years prior to Cahalan’s diagnosis, by neurologist Josep Dalmau, then at the University of Pennsylvania. This diagnosis was much-needed good news for sufferers of the mysterious condition—their disease was treatable. After receiving immunotherapy, Cahalan was able to fully recover. © 1986–2022 The Scientist.

Keyword: Schizophrenia; Neuroimmunology
Link ID: 28289 - Posted: 04.20.2022

Joan L. Luby, M.D., John N. Constantino, M.D., Deanna M. Barch, Ph.D. Numerous studies of children in the US across decades have shown striking correlations between poverty and less-than-optimal physical and mental health and developmental outcomes. Trauma, poor health care, inadequate nutrition, and increased exposures to psychosocial stress and environmental toxins—all of which have significant negative developmental impact—are likely to be involved. The effects of elevated stress on child-caregiver relationships appear to be particularly detrimental, unsurprising in that nurturing and supportive caregiver relationships are foundational for healthy development in early childhood. For adults whose job options are unconducive to their role as parents (such as working multiple jobs or night shift hours), or for whom family support is unavailable, or for those do not have the material resources they need, the resulting stress may result in sleep disruption, depression, and anxiety—all of which translate to poor developmental trajectories for their children. Other health and developmental risks often associated with poverty include lead and other pollutants in air and water, poor nutrition (often related to living in “food desert” areas where healthy foods such as fresh fruits and vegetables are scarce), neighborhood violence, and trauma. “Toxic stress” that exceeds a child’s ability to adapt can occur when the burden of stressful life experience overwhelms the brain’s regulatory capacity, or when the compensatory abilities of brain and body are compromised. A lack of cognitive stimulation (due to such factors as the absence of books and educational materials in the home, poor immersion in language, and a lack of after school or other enrichment activities) or disruption of sleep and circadian rhythms (by neighborhood noise or parents’ irregular work schedules) is likely to impact brain development and emotional and behavioral regulation when these systems are rapidly developing. © 2022 The Dana Foundation.

Keyword: Development of the Brain; Brain imaging
Link ID: 28288 - Posted: 04.16.2022

By Sabrina Imbler 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. One morning in the Panamanian rainforest, a small fruit bat sized up his competition. The odds did not appear to be in his favor. The winged mammal, a Seba’s short-tailed bat, weighed about half an ounce. But his six opponents, fringe-lipped bats, were twice as heavy and occupying the shrouded corner where the small bat wanted to roost. Even worse, the larger bats are known to feast on small animals, such as frogs, katydids and smaller bats — including Seba’s short-tailed bats. None of this fazed the Seba’s short-tailed bat, which proceeded to scream, shake his wings and hurl his body at the posse of bigger bats, slapping one in the face more than 50 times. “I’ve never seen anything like it,” said Ahana Aurora Fernandez, a behavioral biologist at the Natural History Museum, Berlin, who viewed a recording of the bats but was not involved in the research that produced it. “It’s one bat against six,” Dr. Fernandez said. “He shows no fear at all.” The tiny bat’s belligerence paid off as the big bats fled. The corner clear, the Seba’s short-tailed bat moved in, joined a minute later by his female companion, who had nonchalantly watched the fight from nearby. This fun-size brawl and two similar bat bullying incidents in other roosts were observed by Mariana Muñoz-Romo, a biologist at the Smithsonian Tropical Research Institute, and her colleagues, who had been monitoring the sexual preferences of the larger fringe-lipped bats. In a paper published in March in the journal Behaviour, they asked how often tiny bats antagonize bigger ones. When it comes with a risk of being eaten, why pick a fight? The researchers originally set out to study fringe-lipped bats, who were recently discovered to smear a sticky, fragrant substance on their arms, potentially to attract mates. The animals also have impressive appetites, and have been observed eating sizable frogs. © 2022 The New York Times Company

Keyword: Aggression; Hearing
Link ID: 28287 - Posted: 04.16.2022

By Sharon Oosthoek Despite their excellent vision, one city-dwelling colony of fruit bats echolocates during broad daylight — completely contrary to what experts expected. A group of Egyptian fruit bats (Rousettus aegyptiacus) in downtown Tel Aviv uses sound to navigate in the middle of the day, researchers report in the April 11 Current Biology. The finding greatly extends the hours during which bats from this colony echolocate. A few years ago, some team members had noticed bats clicking while they flew under low-light conditions. The midday sound-off seems to help the bats forage and navigate, even though they can see just fine. Bats that are active during the day are unusual. Out of the more than 1,400 species, roughly 10 are diurnal. What’s more, most diurnal bats don’t use echolocation during the day, relying instead on their vision to forage and avoid obstacles. They save echolocation for dim light or dark conditions. So that’s why, two years ago, a group of Tel Aviv researchers were surprised when they noticed a bat smiling during the day. They were looking over photos from their latest study of Egyptian fruit bats when they noticed one with its mouth slightly parted and upturned. “When an Egyptian fruit bat is smiling, he’s echolocating — he’s producing clicks with his tongue and his mouth is open,” says Ofri Eitan, a bat researcher at Tel Aviv University. “But this was during the day, and these bats see really well.” When Eitan and his colleagues looked through other photos — thousands of them — many showed smiling bats in broad daylight. The team showed in 2015 that the diurnal Egyptian fruit bats do use echolocation outdoors under various low light conditions, at least occasionally. But the researchers hadn’t looked at whether the bats were echolocating during midday hours when light levels are highest. © Society for Science & the Public 2000–2022.

Keyword: Hearing; Evolution
Link ID: 28286 - Posted: 04.16.2022

Kayt Sukel Each night, as you transition into deep sleep from wakefulness, your body undergoes a remarkable transformation. Your muscles relax. Your breathing slows. Your temperature and blood pressure drop. Even your brain activity changes, decelerating into slow, coordinated waves. Despite these remarkable physiological changes, scientists are now learning that the brain is far from idle during sleep. Rather, it remains hard at work, facilitating memory and learning while uncoupled from the external world. “For a long time, we believed that being awake all day depleted you and that sleep was what was required to restore and reinvigorate the whole body, including the brain,” says Robert Stickgold, a pioneering sleep researcher at Harvard Medical School. “It turns out that rest has very little to do with the function of sleep—rather, our brain is sorting and consolidating the information we learned during the day so we can better access it when it’s needed.” Anyone who has ever pulled an all-nighter knows the effect that sleep deprivation can have on cognitive function, including one’s ability to learn and retain new information. Yet, over the last few decades, neuroscientists across the globe have learned that sleep plays an integral role in memory—and it is a role that is highly conserved across the animal kingdom. To better understand how sleep helps us remember, these researchers have been working to characterize not only the physiological changes observed during sleep, but also the neural mechanisms underlying them. Nearly every animal on earth, from fruit flies to non-human primates, experiences some form of sleep, a naturally recurring state of altered consciousness and inhibited sensory activity. And while the exact amount of time spent in slumber, and the patterns of neural activity, differ from animal to animal, humans are no different. We need sleep to thrive. © 2022 The Dana Foundation.

Keyword: Sleep; Learning & Memory
Link ID: 28285 - Posted: 04.16.2022

by Peter Hess Two separate sets of neurons govern the social difficulties and repetitive behaviors associated with mutations in TSHZ3, a top autism candidate gene, according to a new mouse study. The results could help advance a circuit-level understanding of autism, says co-lead investigator Laurent Fasano, senior researcher at the French National Center for Scientific Research and Aix-Marseille University in Marseille, France. “Although we know that the results obtained with animal models will not necessarily be transposable to humans, we hope that our results will stimulate additional studies that will benefit autistic people.” In the new work, Fasano and his colleagues homed in on cortical projection neurons, which connect the cerebral cortex to other brain regions, and striatal cholinergic interneurons, which produce the chemical messenger acetylcholine in the striatum. Together, these cell types form part of the corticostriatal circuit, the dysfunction of which has been implicated in autism. “Whereas many studies have linked defective development and function of the corticostriatal pathway to autism, there is little evidence for an implication of striatal cholinergic interneurons,” says co-lead investigator Lydia Kerkerian-Le Goff, senior researcher at the French National Center for Scientific Research and Aix-Marseille University. Picking out specific cell types in the corticostriatal circuit and linking them to distinct autism-related behaviors is important, says Michael Ragozzino, professor of behavioral neuroscience at the University of Illinois Chicago, who was not involved in the study. The study’s results suggest that repetitive behaviors and social deficits, autism’s core traits, have different neurobiological roots, he says. “This may also suggest that different therapeutics may need to be developed to effectively treat both symptom domains.” © 2022 Simons Foundation

Keyword: Autism
Link ID: 28284 - Posted: 04.16.2022

By Andrew Jacobs Psychedelic compounds like LSD, Ecstasy and psilocybin mushrooms have shown significant promise in treating a range of mental health disorders, with participants in clinical studies often describing tremendous progress taming the demons of post-traumatic stress disorder, or finding unexpected calm and clarity as they face a terminal illness. But exactly how psychedelics might therapeutically rewire the mind remains an enigma. A group of neuroscientists in London thought advanced neuroimaging technology that peered deep into the brain might provide some answers. They included 43 people with severe depression in a study sponsored by Imperial College London, and gave them either psilocybin, the active ingredient in magic mushrooms, or a conventional antidepressant; the participants were not told which one they would receive. Functional magnetic resonance imaging, which captures metabolic function, took two snapshots of their brain activity — the day before receiving the first dose and then roughly three weeks after the final one. What they found, according to a study published Monday in the journal Nature Medicine, was illuminating, both figuratively and literally. Over the course of three weeks, participants who had been given the antidepressant escitalopram reported mild improvement in their symptoms, and the scans continued to suggest the stubborn, telltale signs of a mind hobbled by major depressive disorder. Neural activity was constrained within certain regions of the brain, a reflection of the rigid thought patterns that can trap those with depression in a negative feedback loop of pessimism and despair. By contrast, the participants given psilocybin therapy reported a rapid and sustained improvement in their depression, and the scans showed flourishes of neural activity across large swaths of the brain that persisted for the three weeks. That heightened connectivity, they said, resembled the cognitive agility of a healthy brain that, for example, can toggle between a morning bout of melancholia, a stressful day at work and an evening of unencumbered revelry with friends. © 2022 The New York Times Company

Keyword: Depression; Drug Abuse
Link ID: 28283 - Posted: 04.13.2022

by Niko McCarty A new miniature, head-mounted microscope can simultaneously record the activity of thousands of neurons at different depths within the brains of freely moving mice. The smallest functional two-photon microscope to date, it can image neurons almost anywhere in the brain, with subcellular resolution. The device, called MINI2P (miniature two-photon microscope), can also collect data from the same cluster of neurons over several weeks, making it useful for long-term behavioral studies. “If you really want to understand what is behind cognition or failures in cognition, like in autism, you need to look at the interaction between neurons,” says lead investigator Edvard Moser, professor of neuroscience at the Kavli Institute for Systems Neuroscience in Trondheim, Norway. Other devices that measure neuronal activity, such as Neuropixels 2.0, record signals from more than 10,000 sites in the brain at once. But they have a low spatial resolution and cannot always determine which specific neuron is firing at any given time. Other miniature microscopes have also, traditionally, relied on visible light, which illuminates the surface of tissue, but are limited to imaging about 2,000 neurons. The new device can monitor a brain area measuring 500 by 500 micrometers and can capture data on more than 10,000 neurons at once. A typical mouse brain is roughly the size of a pea and contains about 85 million neurons. The MINI2P uses infrared light to capture the activity of neurons engineered to express GCaMP, a protein that binds to calcium ions during an action potential and emits a fluorescent signal in reply. The microscope measures that fluorescence using an infrared laser beam. © 2022 Simons Foundation

Keyword: Brain imaging
Link ID: 28282 - Posted: 04.13.2022

Rhitu Chatterjee For the first time in a decade, overdose deaths among teens in the United States rose dramatically in 2020 and kept rising through 2021 as well. That's according to the results of a new study published Tuesday in JAMA. "This is very alarming because what we've seen in other parts of the population is that when overdose death rates start to rise, they tend to continue to do so for quite some time," says Joe Friedman, a public health researcher at the University of California, Los Angeles, and the lead author of the new study. "We're still really in the early days in terms of teen overdose. And that makes this an especially important time to intervene," he adds. Friedman and his colleagues found that fatal overdoses among adolescents nearly doubled from 492 in 2019 to 954 in 2020, an increase of 94%. There was an additional 20% rise in 2021 compared to the previous year. The highest rates were among Native American and Alaskan Native teens, followed by Latino teens. "For decades, we've seen overdose rates rising among adults, and teens have been insulated from that," says Friedman. "And now, for the first time, the overdose crisis is reaching teens as well." It appears that the rise in deaths was fueled not by greater numbers of teens using drugs – substance use in this age group actually went down during the pandemic – but by use of dangerous and highly potent forms of fentanyl. The study found that fentanyl-related deaths increased from 253 in 2019 to 680 the following year. And in 2021, 77% of all teen overdose deaths involved fentanyl. © 2022 npr

Keyword: Drug Abuse
Link ID: 28281 - Posted: 04.13.2022

By Jake Buehler Earthen piles built by a chicken-like bird in Australia aren’t just egg incubators — they may also be crucial for the distribution of key nutrients throughout the ecosystem. In the dry woodlands of South Australia, sandy mounds rise between patches of many-stemmed “mallee” eucalyptus trees. These monuments — big enough to smother a parking space — are nests, painstakingly constructed by the malleefowl bird. By inadvertently engineering a patchwork of nutrients and churned soil, the industrious malleefowl may be molding surrounding plant and soil communities and even blunting the spread of fire, researchers report March 27 in the Journal of Ecology. Such ecosystem impacts suggest malleefowl conservation could benefit many species, says Heather Neilly, an ecologist at the Australian Landscape Trust in Calperum Station. The species is currently listed as “vulnerable” and declining by the International Union for Conservation of Nature. Some animals — termed “ecosystem engineers” — produce habitats for other species by shaping the environment around them. Beavers build dams that create homes for pond-dwelling lifeforms. In deserts, owls and giant lizards support plant and animal life with their burrows (SN: 10/8/19; SN: 1/19/21). “In Australia in particular, the focus has largely been on our array of digging mammals,” Neilly says. But malleefowl (Leipoa ocellata) — found throughout western and southern Australia — also perturb the soil. They and their close relatives are “megapodes,” a group of fowl native to Australasia and the South Pacific that have the unusual habit of incubating their eggs much like alligators do: in a massive pile of rotting compost. Heat from the decaying vegetation — locked in with an insulating sand layer on top — regulates the eggs’ temperature, and the young scratch their way to the surface upon hatching. © Society for Science & the Public 2000–2022.

Keyword: Sexual Behavior; Evolution
Link ID: 28280 - Posted: 04.13.2022

By Annie Roth and Hisako Ueno The reign of Japan’s monkey queen has just begun. Last year, Yakei, a 9-year-old female Japanese macaque, fought several other macaques, including her own mother, to become the alpha of her troop. That made Yakei the first known female troop leader in the history of Takasakiyama Natural Zoological Garden in Southern Japan, which was established in 1952 and is home to over 1,000 macaques. But during her first breeding season as queen, which began in November 2021 and concluded in March 2022, a messy love triangle threatened to weaken her grip on power. According to officials at the park, the macaque that Yakei showed interest in mating with, a 15-year-old male named Goro, rejected her advances despite their coupling during a previous breeding season. Meanwhile, an 18-year-old macaque named Luffy did his best to woo Yakei, much to her displeasure. Japanese macaques are polyamorous and scientists were worried that Yakei would not be able to maintain her status while pursuing and rejecting potential mates. Tensions run high during breeding season, and a challenge from a spurned male could easily rob Yakei, an average-sized female, of her rank. Yakei rose to power by defeating her troop’s alpha male, but he was elderly and less formidable than the average young male. Fortunately for Yakei, no other macaques attempted to usurp her throne this season and the queen remained the troop’s alpha at the end of March, according to reserve officials. Her continued rule has surprised scientists and given them an opportunity to observe how macaque society functions under a matriarchy. Despite having to maintain her supremacy, Yakei managed to have a successful breeding season. After Goro gave her the cold shoulder, she spent many weeks playing the field, expressing interest in no fewer than five males. Among these males was Chris, a male ranked 10th in the troop, and Shikao, who holds the rank just below Chris. But the only male the reserve is sure she mated with was Maruo. Maruo, Yakei’s mate. © 2022 The New York Times Company

Keyword: Aggression; Sexual Behavior
Link ID: 28279 - Posted: 04.13.2022