Natalia Mesa Cravings for sugary treats and other “wants” in humans are driven by the activity of dopamine-producing cells in our mesolimbic system. Experimental research now suggests that a similar system might also exist in honeybees (Apis mellifera), spurring them to “want” to search for sources of nectar. In a study published today (April 28) in Science, researchers found that bees’ dopamine levels were elevated during the search for food and dropped once the food was consumed. Dopamine may also help trigger a hedonic, or pleasant, “memory” of the sugary treat, the researchers say, as dopamine levels rose again when foragers danced to tell other foragers about the foods’ locations. “The whole story is new. To show that there is a wanting system in insects is generally new,” says study coauthor Martin Giurfa, a neuroscientist at Paul Sabatier University in Toulouse, France. “Bees are truly amazing.” In both humans and invertebrates, dopamine is known to be involved in learning and reward. Giurfa and his team have been studying the neurotransmitter in bees, and several years ago, they characterized many of the neural pathways that involved dopamine. “We found so many so diverse pathways that we said, ‘There might be more than just representing reinforcement, representing punishment, representing reward.’” He began to look for other roles dopamine might play in honeybee behavior. bee next to pink flower © 1986–2022 The Scientist.

Keyword: Drug Abuse; Evolution
Link ID: 28305 - Posted: 04.30.2022

By Helen Ouyang After an hour-and-a-half bus ride last November, Julia Monterroso arrived at a white Art Deco building in West Hollywood, just opposite a Chanel store and the Ivy, a restaurant famous for its celebrity sightings. Monterroso was there to see Brennan Spiegel, a gastroenterologist and researcher at Cedars-Sinai who runs one of the largest academic medical initiatives studying virtual reality as a health therapy. He started the program in 2015 after the hospital received a million-dollar donation from an investment banker on its board. Spiegel saw Monterroso in his clinic the week before and thought he might be able to help alleviate her symptoms. Monterroso is 55 and petite, with youthful bangs and hair clipped back by tiny jeweled barrettes. Eighteen months earlier, pain seized her lower abdomen and never went away. After undergoing back surgery in September to treat a herniated disc — and after the constant ache in her abdomen worsened — she had to stop working as a housecleaner. Eventually, following a series of tests that failed to reveal any clear cause, she landed in Spiegel’s office. She rated her pain an 8 on a 10-point scale, with 10 being the most severe. Chronic pain is generally defined as pain that has lasted three months or longer. It is one of the leading causes of long-term disability in the world. By some measures, 50 million Americans live with chronic pain, in part because the power of medicine to relieve pain remains woefully inadequate. As Daniel Clauw, who runs the Chronic Pain and Fatigue Research Center at the University of Michigan, put it in a 2019 lecture, there isn’t “any drug in any chronic-pain state that works in better than one out of three people.” He went on to say that nonpharmacological therapy should instead be “front and center in managing chronic pain — rather than opioids, or for that matter, any of our drugs.” Virtual reality is emerging as an unlikely tool for solving this intractable problem. The V.R. segment in health care alone, which according to some estimates is already valued at billions of dollars, is expected to grow by multiples of that in the next few years, with researchers seeing potential for it to help with everything from anxiety and depression to rehabilitation after strokes to surgeons strategizing where they will cut and stitch. In November, the Food and Drug Administration gave authorization for the first V.R. product to be marketed for the treatment of chronic pain. © 2022 The New York Times Company

Keyword: Pain & Touch; Vision
Link ID: 28304 - Posted: 04.27.2022

By Michele Lent Hirsch Sleep problems are a hallmark of modern American life — perhaps never more so than recently. In 2016, the Centers for Disease Control and Prevention found that a third of Americans were getting too little sleep at night. But then came the stressors of the pandemic, job losses, disrupted schedules and closed schools, which kept record numbers of Americans up at night or unable to wake up in the morning. As many as 2 in 3 Americans reported getting either too much or too little sleep, in a survey from the American Psychological Association during the pandemic’s second year. And the insomnia of the past two years may be stubbornly hanging on: Many people continue having more trouble falling asleep or staying asleep or have seen unusual shifts in their sleep schedules. All of this is taking a toll. “These different types of sleep changes seem to be closely related to [problems with] mental health,” says Karianne Dion, a graduate student in clinical psychology at the University of Ottawa. Research she co-wrote, published in the Journal of Sleep Research in 2021, found “worse symptoms of stress, anxiety, and depression” among those who are sleeping less or going to bed later and waking up later than before. Researchers have long known that anxiety and depression can lead to sleeplessness, while sleeping poorly can increase the likelihood of anxiety and depression. But a good night’s rest is also critical for a strong immune system, as well as for health overall. Insufficient sleep over time is associated with a greater risk of diabetes, high blood pressure and heart disease, according to the CDC. It can lead to memory and cognitive issues as well. So how can we get the sleep we need? Here’s how to solve seven common problems that can interfere with your rest and your health. © 1996-2022 The Washington Post

Keyword: Sleep
Link ID: 28303 - Posted: 04.27.2022

By Hope Reese Can we do without love? For many years, the neuroscientist Stephanie Ortigue believed that the answer was yes. Even though she researched the science of human connections, Dr. Ortigue — an only child and, in her 20s and 30s, contentedly single — couldn’t completely grasp its importance in her own life. “I told myself that being unattached made me a more objective researcher: I could investigate love without being under its spell,” she writes in her new book, “Wired for Love: A Neuroscientist’s Journey Through Romance, Loss and the Essence of Human Connection.” But then, in 2011, at age 37, she met John Cacioppo at a neuroscience conference in Shanghai. Dr. Cacioppo, who popularized the concept that prolonged loneliness can be as toxic to health as smoking, intrigued her. The two scientists fell hard for each other and married. She took his last name and they soon became colleagues at the University of Chicago’s Pritzker School of Medicine (where she now directs the Brain Dynamics Laboratory) — forming a team at home and in the lab. “Wired for Love” is the neurobiological story of how love rewires the brain. It’s also a personal love story — one that took a sad turn when John died of cancer in March 2018. Here, Dr. Cacioppo discusses what exactly love does to the brain, how to fight loneliness and how love is, literally, a product of the imagination. You went from being happily single, to coupled, to then losing your husband. How did meeting him bring your research on love to life? Sign Up for Love Letter Your weekly dose of real stories that examine the highs, lows and woes of relationships. This newsletter will include the best of Modern Love, weddings and love in the news. Get it sent to your inbox. When we first met, we spoke for three hours, but I couldn’t feel time go by. I felt euphoria — from the rush of dopamine. I blushed — a sign of adrenaline. We became closer, physically, and started imitating each other. This was from the activation of mirror neurons, a network of brain cells that are activated when you move or feel something, and when you see another person moving. When you have a strong connection with someone, the mirror neuron system is boosted. © 2022 The New York Times Company

Keyword: Sexual Behavior; Emotions
Link ID: 28302 - Posted: 04.27.2022

By Melinda Wenner Moyer The more popular antidepressants become, the more questions they raise. The drugs are one of the most widely prescribed types of medications in the United States, with more than one out of eight Americans over 18 having recently taken them, according to a survey from the Centers for Disease Control and Prevention. Yet we know very little about how well antidepressants work over the long term, and especially how they affect overall quality of life, experts say. Most clinical drug trials have followed people taking antidepressants for only eight to 12 weeks, so it’s unclear what happens when patients take them for longer than that, said Gemma Lewis, a research psychologist at University College London who studies the causes, treatment and prevention of depression and anxiety. “We definitely need longer follow-ups of people who are using or are not using antidepressants, to see what the long-term outcomes are,” Dr. Lewis said. A study published yesterday in the journal PLoS One aimed to close this knowledge gap by comparing, over the course of two years, the changes in quality of life reported by Americans with depression who took antidepressants versus the changes reported by those with the same diagnosis who did not take the medications. The study included people who took all types of antidepressants, including selective serotonin reuptake inhibitors like Prozac, serotonin-norepinephrine reuptake inhibitors like Effexor and older antidepressants such as clomipramine and phenelzine. Researchers assessed both mental and physical quality of life with a survey that asked questions about subjects’ physical health, energy levels, mood, pain and ability to perform daily activities, among other things. The paper found no significant differences in the changes in quality of life reported by the two groups, which suggests that antidepressant drugs may not improve long-term quality of life. Both groups reported slight increases in the mental aspects of quality of life over time, and slight drops in their physical quality of life. But the study is imperfect, researchers say, and it certainly doesn’t settle the debate over the effectiveness of these drugs. © 2022 The New York Times Company

Keyword: Depression
Link ID: 28301 - Posted: 04.27.2022

By Linda Searing Already known to help ease depression, regular exercise may also help prevent it, with people who exercised just half the recommended weekly amount lowering their risk for depression by 18 percent, according to research published in the journal JAMA Psychiatry. However, those who were more active, meeting at least the minimum recommended physical activity level, reduced their risk for depression by 25 percent, compared with inactive people. The findings stem from the analysis of data from 15 studies, involving 191,130 adults who were tracked for at least three years. Those who met activity guidelines did at least 150 minutes a week of moderate-intensity activity, such as brisk walking, as recommended in the Physical Activity Guidelines for Americans. Mental health experts note that nearly 10 percent of American adults struggle with some form of depression each year. Antidepressant medication and talk therapy are commonly prescribed treatments, but exercise is also considered an effective treatment. Exercise sparks the brain’s release of endorphins, sometimes referred to as feel-good hormones. It can also quiet the mind, quelling the cycle of negative thoughts that often accompany depression, and can help reduce stress, improve sleep and boost self-esteem. Urging doctors to encourage their patients to increase their physical activity, the researchers wrote that the study’s findings suggest “significant mental health benefits from being physically active, even at levels below the public health recommendations.” If less-active participants in the study had exercised more, they say, 11.5 percent of depression cases could have been prevented.

Keyword: Depression
Link ID: 28300 - Posted: 04.27.2022

Carrie Arnold Playing the mating game is risky. Organisms must cope with the existential risk that swiping right on the wrong choice could doom future generations to a lifetime of bad genes. They also have to contend with more immediate burdens and risks: Participants need to gather resources for courting and summon energy to pursue a potential partner. Animals engaged in amorous activities also make easy targets for predators. Small wonder, then, that when times are good, the roundworm Caenorhabditis elegans doesn’t bother with the process. As a mostly hermaphroditic species (with a few males thrown in for variety), a C. elegans worm usually self-fertilizes its eggs until its sperm stash is depleted late in life; only then does it produce a pheromone to attract males and stay in the reproductive game. But when environmental conditions become stressful, the worms become sexually attractive much sooner. For them, sex is the equivalent of a Hail Mary pass — a desperate gamble that if their offspring are more genetically diverse, some will fare better under the new, rougher conditions. Scientists thought this stress-induced shift was purely fleeting. But recently when scientists at Tel Aviv University raised C. elegans in too-warm conditions for more than 10 generations, they discovered that the worms continued to be sexually attractive for several more generations after they were moved to cooler surroundings. It’s an observation that highlights how inheritance does not always reduce to a simple accounting of the genes in organisms, and it may point to a mechanism that works in tandem with traditional natural selection in shaping the evolution of some organisms. As the new paper in Developmental Cell shows, the cause of this trait wasn’t a genetic change to the worm’s DNA but rather an inherited “epigenetic” change that influenced how the DNA was used. The researchers — senior author Oded Rechavi, a biologist at Tel Aviv University, first author Itai Toker (now a postdoctoral fellow at Columbia University) and their colleagues — identified a small RNA molecule that can be passed between generations to signal for production of the pheromone. In effect, this heritable RNA molecule improves the odds that the worms will evolve in stressful times. All Rights Reserved © 2022

Keyword: Sexual Behavior; Epigenetics
Link ID: 28299 - Posted: 04.23.2022

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