Chapter 8. Hormones and Sex

Follow us on Facebook or subscribe to our mailing list, to receive news updates. Learn more.


Links 1 - 20 of 3175

By Azeen Ghorayshi An upsurge in teenagers requesting hormones or surgeries to better align their bodies with their gender identities has ignited a debate among doctors over when to provide these treatments. An international group of experts focused on transgender health last month released a draft of new guidelines, the gold standard of the field that informs what insurers will reimburse for care. Many doctors and activists praised the 350-page document, which was updated for the first time in nearly a decade, for including transgender people in its drafting and for removing language requiring adults to have psychological assessments before getting access to hormone therapy. But the guidelines take a more cautious stance on teens. A new chapter dedicated to adolescents says that they must undergo mental health assessments and must have questioned their gender identity for “several years” before receiving drugs or surgeries. Experts in transgender health are divided on these adolescent recommendations, reflecting a fraught debate over how to weigh conflicting risks for young people, who typically can’t give full legal consent until they are 18 and who may be in emotional distress or more vulnerable to peer influence than adults are. Some of the drug regimens bring long-term risks, such as irreversible fertility loss. And in some cases, thought to be quite rare, transgender people later “detransition” to the gender they were assigned at birth. Given these risks, as well as the increasing number of adolescents seeking these treatments, some clinicians say that teens need more psychological assessment than adults do. “They absolutely have to be treated differently,” said Laura Edwards-Leeper, a child clinical psychologist in Beaverton, Ore., who works with transgender adolescents. Dr. Edwards-Leeper was one of seven authors of the new adolescent chapter, but the organization that publishes the guidelines, the World Professional Association for Transgender Health, did not authorize her to comment publicly on the draft’s proposed wording. © 2022 The New York Times Company

Keyword: Sexual Behavior; Hormones & Behavior
Link ID: 28156 - Posted: 01.15.2022

By Sabrina Imbler Common bottlenose dolphins have sex frequently — very likely multiple times in a day. Copulation lasts only a few seconds, but social sex, which is used to maintain social bonds, can last much longer, happen more frequently and involve myriad heterosexual and homosexual pairings of dolphins and their body parts. Anything is possible, and, as new research suggests, probably pleasurable for swimmers of both sexes. According to a paper published on Monday in the journal Current Biology, female bottlenose dolphins most likely experience pleasure through their clitorises. The findings come as little surprise to scientists who research these dolphins. “The only thing that surprises me is how long it has taken us as scientists to look at the basic reproductive anatomy,” Sarah Mesnick, an ecologist at NOAA Fisheries who was not involved with the research, said, speaking of the clitoris. She added, “It took a team of brilliant women,” referring to two of the authors. “A lot of people assume that humans are unique in having sex for pleasure,” Justa Heinen-Kay, a researcher at the University of Minnesota who was not involved with the paper, wrote in an email. “This research challenges that notion.” And learning more about the anatomy of marine mammals’ genitalia has clear implications for their survival, Dr. Mesnick said: “The more we know about the social behavior of these animals, the better we’re able to understand their evolution and help use that to manage and conserve them.” Historically, researchers have focused on male genitalia, driven by prejudice toward male subjects, prejudice against female choice in sexual selection and the fact that it can be easier to study something that sticks out. “Female genitalia were assumed to be simple and uninteresting,” Dr. Heinen-Kay said. “But the more that researchers study female genitalia, the more we’re learning that this isn’t the case at all.” She added that this shift may be driven in part by the increasing number of women researchers. © 2022 The New York Times Company

Keyword: Sexual Behavior; Evolution
Link ID: 28147 - Posted: 01.12.2022

Jon Hamilton When baby mice cry, they do it to a beat that is synchronized to the rise and fall of their own breath. It's a pattern that researchers say could help explain why human infants can cry at birth — and how they learn to speak. Mice are born with a cluster of cells in the brainstem that appears to coordinate the rhythms of breathing and vocalizations, a team reports in the journal Neuron. If similar cells exist in human newborns, they could serve as an important building block for speech: the ability to produce one or many syllables between each breath. The cells also could explain why so many human languages are spoken at roughly the same tempo. "This suggests that there is a hardwired network of neurons that is fundamental to speech," says Dr. Kevin Yackle, the study's senior author and a researcher at the University of California, San Francisco. Scientists who study human speech have spent decades debating how much of our ability is innate and how much is learned. The research adds to the evidence that human speech relies — at least in part — on biological "building blocks" that are present from birth, says David Poeppel, a professor of psychology and neural science at New York University who was not involved in the study. But "there is just a big difference between a mouse brain and a human brain," Poeppel says. So the human version of this building block may not look the same. © 2022 npr

Keyword: Language; Evolution
Link ID: 28144 - Posted: 01.08.2022

by Peter Hess Of all the brain chemistry that autism researchers study, few molecules have garnered as much attention as the so-called ‘social hormone,’ oxytocin. Some autistic children appear to have low blood levels of oxytocin, which has led several teams to test oxytocin delivered intranasally as an autism therapy. So far, though, such clinical trials have yielded inconsistent results. Here we explain what scientists know so far about oxytocin’s connection to autism. What does oxytocin do in the brain and body? Oxytocin serves multiple purposes, such as promoting trust between people, moderating our response to threats, and supporting lactation and mother-child bonding. The hormone is produced primarily in the hypothalamus, a brain region that mediates basic bodily functions, including hunger, thirst and body temperature. Oxytocin-producing neurons in the hypothalamus project into other parts of the brain, such as the nucleus accumbens, where the hormone regulates social-reward learning. In the brain’s sensory system, including the olfactory bulb, oxytocin seems to help balance excitatory and inhibitory signals, improving social-information processing, at least in rats. In the amygdala, oxytocin appears to help dull threat responses to negative social information and foster social recognition. The pituitary gland controls the release of oxytocin into the bloodstream. Blood oxytocin is crucial to start uterine muscle contractions during childbirth. It also supports lactation by facilitating the milk letdown reflex, stimulating the flow of milk into the nipple. © 2022 Simons Foundation

Keyword: Hormones & Behavior; Autism
Link ID: 28143 - Posted: 01.08.2022

By Bruce Bower Evidence that cross-continental Stone Age networking events powered human evolution ramped up in 2021. A long-standing argument that Homo sapiens originated in East Africa before moving elsewhere and replacing Eurasian Homo species such as Neandertals has come under increasing fire over the last decade. Research this year supported an alternative scenario in which H. sapiens evolved across vast geographic expanses, first within Africa and later outside it. The process would have worked as follows: Many Homo groups lived during a period known as the Middle Pleistocene, about 789,000 to 130,000 years ago, and were too closely related to have been distinct species. These groups would have occasionally mated with each other while traveling through Africa, Asia and Europe. A variety of skeletal variations on a human theme emerged among far-flung communities. Human anatomy and DNA today include remnants of that complex networking legacy, proponents of this scenario say. It’s not clear precisely how often or when during this period groups may have mixed and mingled. But in this framework, no clear genetic or physical dividing line separated Middle Pleistocene folks usually classed as H. sapiens from Neandertals, Denisovans and other ancient Homo populations. “Middle Pleistocene Homo groups were humans,” says paleoanthropologist John Hawks of the University of Wisconsin–Madison. “Today’s humans are a remix of those ancient ancestors.” © Society for Science & the Public 2000–2021.

Keyword: Evolution; Sexual Behavior
Link ID: 28111 - Posted: 12.15.2021

By Pam Belluck What if something in the blood of an athlete could boost the brainpower of someone who doesn’t or can’t exercise? Could a protein that gets amplified when people exercise help stave off symptoms of Alzheimer’s and other memory disorders? That’s the tantalizing prospect raised by a new study in which researchers injected sedentary mice with blood from mice that ran for miles on exercise wheels, and found that the sedentary mice then did better on tests of learning and memory. The study, published Wednesday in the journal Nature, also found that the type of brain inflammation involved in Alzheimer’s and other neurological disorders was reduced in sedentary mice after they received their athletic counterparts’ blood. “We’re seeing an increasing number of studies where proteins from outside the brain that are made when you exercise get into the brain and are helpful for improving brain health, or even improving cognition and disease,” said Rudolph Tanzi, a professor of neurology at Massachusetts General Hospital and Harvard Medical School. He led a 2018 study that found that exercise helped the brains of mice engineered to have a version of Alzheimer’s. The most promising outcome would be if exercise-generated proteins can become the basis for treatments, experts said. The study, led by researchers at Stanford School of Medicine, found that one protein — clusterin, produced in the liver and in heart muscle cells — seemed to account for most of the anti-inflammatory effects. But several experts noted that recent studies have found benefits from other proteins. They also said more needs to be learned about clusterin, which plays a role in many diseases, including cancer, and may have negative effects in early stages of Alzheimer’s before brain inflammation becomes dominant. © 2021 The New York Times Company

Keyword: Alzheimers; Hormones & Behavior
Link ID: 28108 - Posted: 12.11.2021

By Elizabeth Preston A person trying to learn the way around a new neighborhood might spend time studying a map. You would probably not benefit from being carried rapidly through the air, upside-down in the dark. Yet that’s how some baby bats learn to navigate, according to a study published last month in Current Biology. As their mothers tote them on nightly trips between caves and certain trees, the bat pups gain the skills they need to get around when they grow up. Mothers of many bat species carry their young while flying, said Aya Goldshtein, a behavioral ecologist at the Max Planck Institute of Animal Behavior in Konstanz, Germany. Egyptian fruit bats, for example, are attached to their mothers continuously for the first three weeks of life. While a mother searches for food, her pup clings to her body with two feet and its jaw, latching its teeth around her nipple. Mothers can still be seen flying with older pups that weigh 40 percent of what they do. It hadn’t been clear why the moms go to this length, instead of leaving pups in the cave where they roost, as some other species do. Dr. Goldshtein worked with Lee Harten, a behavioral ecologist at Tel Aviv University in Israel, where both she and Dr. Goldshtein were graduate students at the time in the lab of Yossi Yovel, a study co-author, to make sense of this maternal mystery. The researchers captured Egyptian fruit bat mothers and pups from a cave just outside Tel Aviv. They attached a tag holding a radio transmitter and miniature GPS device to each bat’s fur that would drop off after a couple of weeks. Then, the researchers brought the bats back to their cave. To track the bats, Dr. Harten held an antenna while standing on the roof of a 10-story building with a view of the cave. She directed Dr. Goldshtein, who was on foot or in a car with her own antenna, to follow the radio signals of bat pairs as they flew out at night. But again and again, there was a problem: The pup’s movement would suddenly stop, while the mother’s signal disappeared. “At the beginning we thought that we were doing our job wrong, and just losing the bats,” Dr. Harten said. © 2021 The New York Times Company

Keyword: Learning & Memory; Animal Migration
Link ID: 28102 - Posted: 12.08.2021

By Sabrina Imbler The male Bornean rock frog cannot scream over the sound of a waterfall. Instead, he threatens other frogs with his feet. The frog intimidates his male competitors with a can-can-like gesture: kicking his leg up into the air, fully extending his splayed foot, and dragging it down toward the ground. This foot-flagging display may not sound threatening to a human, but its effect has to do with a frog’s visual perception. To a frog, the world contains two kinds of objects: things that are worms, and things that are not worms. If a frog sees a skinny object moving parallel to its long axis — like how a worm travels along the ground — it sees dinner. But if a frog sees a similar shape moving perpendicular its long axis — very unlike a worm — it sees a threat to flee from. Scientists call this latter movement the anti-worm stimulus, and it strikes fear into the hearts of frogs. Frogs likely evolved this visual system to hunt worms and stay safe from larger predators. Now, researchers suggest some male frogs have evolved to take advantage of their froggy brethren’s fears by kicking and lowering their legs in a gesture that looks a lot like an anti-worm signal, as a way to frighten their competition. In a paper published Wednesday in Proceedings of the Royal Society B, researchers reveal that they could amplify the foot-flagging behavior of Bornean rock frogs by giving the frogs a dose of testosterone. The hormone acts on the muscles in the frog’s leg to exaggerate the gesture, meaning the more testosterone coursing through the frog, the bigger the foot-flagging display. This flamboyant foot display, intensified by the sex hormone, suggests the frogs evolved a way to exploit their competitors’ unusual visual system to appear more dangerous to other frogs. © 2021 The New York Times Company

Keyword: Aggression; Hormones & Behavior
Link ID: 28087 - Posted: 11.20.2021

by Angie Voyles Askham An intranasal form of the hormone oxytocin is no more effective than placebo at increasing social behaviors in autistic children, according to what may be the largest clinical trial of the treatment to date. The results were published today in The New England Journal of Medicine. Because of oxytocin’s role in strengthening social bonds, researchers have considered it as a candidate treatment for autism for more than a decade. Small trials hinted that the hormone could improve social skills in some autistic people, such as those with low blood levels of oxytocin or infants with Prader-Willi syndrome, an autism-related condition. But the new results, based on 250 autistic children, suggest that “oxytocin, at least in its current form, is probably not helpful for the majority of kids with autism,” says Evdokia Anagnostou, professor of pediatrics at University of Toronto in Canada, who was not involved in the new work. The null results “change things,” says lead researcher Linmarie Sikich, associate professor of psychiatry and behavioral sciences at the Duke Center for Autism and Brain Development in Durham, North Carolina. “Most people still felt like there was a good chance that this would be treatment for many people with autism.” This type of research is prone to publication bias, in which non-significant results are less likely to be published than significant ones, says Daniel Quintana, senior researcher in biological psychiatry at the University of Oslo in Norway, who was not involved in the study. For that reason, the new work is “an important contribution to the field,” he says, but “it does not alone put to rest the idea of using intranasal oxytocin as an autism treatment.” © 2021 Simons Foundation

Keyword: Autism; Hormones & Behavior
Link ID: 28036 - Posted: 10.16.2021

By Jamie Friedlander Serrano My dad was planning a trip to Cannon Beach, a small coastal town in Oregon that I love. Yet when I sat down to email him some recommendations, I drew a blank. I couldn’t remember the name of the state park we visited or the breakfast spot we adored. Even the name of the hotel we stayed at eluded me. U.S. coronavirus cases tracker and map Since giving birth to my year-old daughter, I’ve had countless moments like this. I have trouble recalling words, forget to respond to text messages, and even missed an appointment. What I’m experiencing is often called “mommy brain”— the forgetful, foggy and scatterbrained feeling many pregnant women and new mothers experience. But is mommy brain real? Anecdotally, yes. Ask any new mom if she has felt the above, and she'll likely say she has — as many as 80 percent of new moms report feelings of mommy brain. Scientifically, it also appears the answer is yes: A growing body of research supports the argument that moms' brains change during pregnancy and after giving birth. A clear explanation for the phenomenon still remains somewhat elusive, however. There are countless variables that experts say contribute to mommy brain, such as fluctuating hormones postpartum, sleep deprivation in dealing with a new baby, anxiety over new parenthood, elevated stress levels, and a general of lives that having a baby forces. Put together, it’s only natural that changes in mental processing would occur, says Moriah Thomason, Barakett associate professor of child and adolescent psychiatry at New York University School of Medicine. When our brain needs to make space for a new priority — keeping a baby alive — remembering a grocery list takes a back seat. “Does it mean that you literally cannot do those things that you used to do as well? Probably not,” she says. “It’s just not the most important thing for you to be accessing.” © 1996-2021 The Washington Post

Keyword: Hormones & Behavior; Sexual Behavior
Link ID: 28033 - Posted: 10.13.2021

Allison Aubrey The "diet" in diet drinks may be a false promise for some soda lovers. True, they deliver the fizz and taste of a soda experience, without the calories. Yet, new research shows they also can leave people with increased food cravings. A study published recently in JAMA Network Open adds to the evidence that drinks made with sucralose may stimulate the appetite, at least among some people, and the study gives some clues as to why. "We found that females and people with obesity had greater brain reward activity" after consuming the artificial sweetener, says study author Katie Page, a physician specializing in obesity at the University of Southern California. Both groups also had a reduction in the hormone that inhibits appetite, and they ate more food after they consumed drinks with sucralose, compared with after regular sugar-sweetened drinks. In contrast, the study found males and people of healthy weight did not have an increase in either brain reward activity or hunger response, suggesting they're not affected in the same way. The study notes that most earlier research focused on males and people of normal weight. But this finding suggests that diet drinks sweetened with sucralose could be disadvantageous to the people who could benefit most from an effective diet strategy. © 2021 npr

Keyword: Obesity; Sexual Behavior
Link ID: 28027 - Posted: 10.09.2021

By Tara Ellison As menopause hit, I found I wasn’t as interested in intimacy as I used to be. Sex started to feel like a box that needed to be checked a couple of times a week, and that was causing problems in my marriage. But it wasn’t just sex. I felt was slowing down in many areas. After hot flashes in my 40s had sent me running to the gynecologist for help, I’d been using bioidentical creams to balance my declining hormones. When, at 51, I confided to a friend that I’d had limited success with what my doctor prescribed, she said that she was thriving on something called hormonal “pellets.” I grilled her about them and then made an appointment with her practitioner, an internal medicine doctor. He ordered extensive lab work, which showed that my testosterone levels were very low, which can happen with aging. The doctor said I had two options: do nothing, which he said would eventually likely lead to loss of muscle, decreased bone density and a host of other health complications. Or up my testosterone. Testosterone therapy for women is a hotly debated subject. Studies suggest that testosterone can heighten libido in women with hypoactive sexual desire disorder (HSDD), at least in the short term. A recent statement by a group of international medical societies involved with women’s health endorsed the use of testosterone therapy in women for HSDD, and specifically excluded pellets and injectables as “not recommended.” It also cautioned there was not enough data to support the use of testosterone therapy for cognitive performance.

Keyword: Sexual Behavior; Hormones & Behavior
Link ID: 28009 - Posted: 09.29.2021

By Kimberly Hickok Seahorses are some of the most dazzling fish in the sea. They’re also the only group of animals in which the males, not the females, go through pregnancy and give birth. Now, new research finds the male’s brood pouch—which can hold up to 1000 baby seahorses at a time—develops and functions like a human placenta. “Evolution is just mind boggling,” says Camilla Whittington, an evolutionary biologist at the University of Sydney who led the new work. The study is the first to thoroughly examine how males nurture their young brood while they’re still in the pouch, says Mari Kawaguchi, an evolutionary biologist at Sophia University in Tokyo. Kawaguchi, who has studied seahorses for some 2 decades, has long suspected pregnant seahorses develop something resembling a placenta. Now, at last, there’s proof. Male seahorses start their path toward fatherhood with a dance. They twirl together with their chosen female under the water, changing colors and linking tails as they pirouette around a shared holdfast. Next, they align the female’s ovipositor with the male’s pouch opening so the female can deposit her eggs. Once the deed is done, the male gently sways to settle the eggs. Ten days to 6 weeks later, depending on the species, the male spends hours in labor, pumping and thrusting to force hundreds of tiny babies out into the water. There, they drift until they are grown. As for dad, he is ready for another round of courtship within hours after birth. But during pregnancy, males have one goal: Provide the embryos with everything they need, from oxygen to nutrients to antibodies. “One of the biggest challenges that all pregnant parents have is getting oxygen to their embryos and carbon dioxide away from the embryos,” Whittington says. “That’s really what motivated our study–how do those baby seahorses actually breathe, if you will, inside the brood pouch?” © 2021 American Association for the Advancement of Science.

Keyword: Sexual Behavior; Evolution
Link ID: 28004 - Posted: 09.25.2021

By Leigh Weingus I’ve struggled with sleep since I was a teenager, and have spent almost as long trying to fix it. I’ve absorbed countless books and articles on getting better sleep that instructed me to go blue-light free at least two hours before bedtime, take nightly baths to lower my body temperature, keep my phone far from my bedroom and avoid caffeine after 12 p.m. In between all my diligent sleep hygiene work, I couldn’t help but feel like there was a larger force at play. My sleep seemed to change throughout my menstrual cycle, for example, getting worse in the days before my period and significantly better afterward. When I was pregnant, I experienced the best sleep of my life, and when I stopped breastfeeding, I didn’t sleep for days. I finally started to ask myself: When we talk about getting better sleep, why aren’t we talking more about hormones? According to the National Sleep Foundation, the lifetime risk of insomnia is 40 percent higher for women than it is for men. Blaming this discrepancy entirely on hormones oversimplifies it — women also tend to take on the bulk of household worrying and emotional labor, and they tend to experience higher levels of anxiety. But according to Mary Jane Minkin, an obstetrician-gynecologist and clinical professor in the Department of Obstetrics, Gynecology, and Reproductive Sciences at the Yale School of Medicine, anecdotal evidence and studies suggest that hormones likely play a role.

Keyword: Sleep; Hormones & Behavior
Link ID: 28000 - Posted: 09.22.2021

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

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

by Rachel Zamzow The X chromosome holds stronger-than-expected genetic sway over the structure of several brain regions, a new study finds. The X-linked genes that may underlie this oversized influence have ties to autism and intellectual disability. “There were already hints that the X chromosome was likely to be conspicuous, with how involved it is with the brain,” says lead investigator Armin Raznahan, chief of the section on developmental neurogenomics at the U.S. National Institute of Mental Health. Many X chromosome genes — including those at the root of several autism-related conditions, such as fragile X syndrome and Rett syndrome — are expressed in the brain, for example. But the new findings suggest that the X chromosome, despite containing only 5 percent of the human genome, has a privileged role in shaping the brain — one that may be particularly relevant to developmental conditions. What’s more, this influence may be stronger in men than in women, the study shows. “What they’re showing is X is fundamentally different,” says David Glahn, professor of psychology at Harvard University, who was not involved in the new study. “It’s off the scale.” Research over the past decade has linked genetic variation to shifts in brain features, such as overall size or patterns of connectivity between regions, Glahn says. But “the X chromosome and the Y chromosome are fundamentally understudied,” because including them requires extra analytical legwork, he says. © 2021 Simons Foundation

Keyword: Development of the Brain; Genes & Behavior
Link ID: 27992 - Posted: 09.15.2021

Sophie Fessl The hormone irisin is necessary for the cognitive benefits of exercise in healthy mice and can rescue cognitive decline associated with Alzheimer’s disease, according to a study published August 20 in Nature Metabolism. According to the authors, these results support the hypothesis that irisin undergirds the cognitive benefits of exercise—a link that has been long debated. In addition, this study has “paved the way for thinking whether irisin could be a therapeutic agent against Alzheimer’s disease,” says biologist Steffen Maak with the Leibniz Institute for Farm Animal Biology in Germany, who has been critical of the methods used to study irisin in the past and was not involved in the study. Many studies have found that exercise is good for the brain, but the molecular mechanisms responsible for the cognitive boost have remained elusive. During her postdoctoral studies, neuroscientist Christiane Wrann found that the gene that codes for irisin becomes highly expressed in the brain during exercise—one of the first studies linking irisin with the brain. See “Irisin Skepticism Goes Way Back” When she joined the faculties at Massachusetts General Hospital and Harvard Medical School, she decided to investigate the hormone further. Wrann, who holds a patent related to irisin and is academic cofounder and consultant for Aevum Therapeutics, a company developing drugs that harness the protective molecular mechanisms of exercise to treat neurodegenerative and neuromuscular disorders, began to investigate whether irisin mediates the positive effects of exercise on the brain. © 1986–2021 The Scientist.

Keyword: Learning & Memory; Hormones & Behavior
Link ID: 27985 - Posted: 09.13.2021

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

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

by Angie Voyles Askham Male mice exposed to atypically low levels of a placental hormone in the womb have altered brain development and asocial behaviors, according to a new study. The findings may help explain why preterm birth — which coincides with a deficiency in hormones made by the placenta — is linked to an increased likelihood of having autism. The hormone, called allopregnanolone, crosses the blood-brain barrier, binds to receptors for the chemical messenger gamma-aminobutyric acid (GABA) and helps regulate aspects of neurodevelopment, including the growth of new neurons. Its levels typically peak in the fetus during the second half of gestation. In the new study, researchers engineered a mouse model to have low fetal levels of allopregnanolone, mimicking the hormone’s loss due to preterm birth or placental dysfunction. The male mice in particular have structural changes in the cerebellum, a brain region known for balance and motor control, and exhibit more pronounced autism-like traits than control mice or female model mice. The new model “has a good translational potential for understanding the underlying mechanisms of sex differences in neurodevelopmental conditions such as autism,” says Amanda Kentner, professor of psychology at the Massachusetts College of Pharmacy and Health Sciences in Boston, who was not involved in the work. Injecting a pregnant mouse with allopregnanolone partway through gestation decreased the likelihood that its offspring would have autism-like traits, the researchers found. © 2021 Simons Foundation

Keyword: Autism; Development of the Brain
Link ID: 27977 - Posted: 09.04.2021

Nicola Davis Premature babies appear to feel less pain during medical procedures when they are spoken to by their mothers, researchers have found. Babies that are born very early often have to spend time in neonatal intensive care units, and may need several painful clinical procedures. The situation can also mean lengthy separation from parents. Now researchers say they have found the sound of a mother’s voice seems to decrease the pain experienced by their baby during medical procedures. Dr Manuela Filippa, of the University of Geneva and first author of the study, said the research might not only help parents, by highlighting that they can play an important role while their baby is in intensive care, but also benefit the infants. Advertisement Last man out: the haunting image of America’s final moments in Afghanistan “We are trying to find non-pharmacological ways to lower the pain in these babies,” she said, adding that there was a growing body of evidence that parental contact with preterm babies could be important for a number of reasons, including attachment. Filippa said the team focused on voice because it was not always possible for parents to hold their babies in intensive care, while voice could be a powerful tool to share emotion. Mothers’ voices were studied in particular because infants would already have heard it in the womb. But Filippa said that did not mean a father’s voice could not become as familiar over time. “We are [also] running studies on fathers’ vocal contacts,” she said. Writing in the journal Scientific Reports, Filippa and colleagues at the University of Geneva, Parini hospital in Italy and the University of Valle d’Aosta, report how they examined the pain responses of 20 premature babies in neonatal intensive care to a routine procedure in which the foot is pricked and a few drops of blood collected. © 2021 Guardian News & Media Limited

Keyword: Pain & Touch; Development of the Brain
Link ID: 27973 - Posted: 09.01.2021