Links for Keyword: Hormones & Behavior

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By Sabrina Malhi Researchers have found a possible link between the common hormone disorder PCOS and cognitive decline later in life. PCOS, which stands for polycystic ovary syndrome, is the most common endocrine disorder among women ages 15 to 44. However, it is often underdiagnosed because many of its symptoms, including abnormal menstrual cycles and excess hair, can be attributed to other causes. The syndrome was first described in 1935 by American gynecologists Irving F. Stein and Michael L. Leventhal. They published a paper documenting a group of women with lack of periods, excess body hair and enlarged ovaries with multiple cysts. Their work helped identify and characterize PCOS as it is known today. Health experts hypothesize that genetic factors could contribute to the development of the condition, but the exact causes are still unknown. Here’s what to know about PCOS and its potential link to cognitive health. PCOS is a chronic hormonal disorder characterized by overproduction of androgens, which are typically considered male hormones. High androgen levels can lead to irregular menstrual cycles and fertility issues when excessively produced in women. In the United States, 6 to 12 percent of people assigned female at birth who are of reproductive age are affected by PCOS, according to data from the Centers for Disease Control and Prevention. The condition is associated with an increased risk of obesity, high blood pressure, high cholesterol and endometrial cancer. PCOS is also often linked to insulin resistance, which can result in elevated blood sugar levels and an escalated risk of Type 2 diabetes. The condition can contribute to various metabolic issues, including high blood pressure, excess abdominal fat, and abnormal cholesterol or triglyceride levels. People with PCOS face an elevated risk of developing cardiovascular problems, such as high blood pressure, high cholesterol levels and an increased risk of heart disease. A recent study in the journal Neurology found that people with PCOS performed lower than normal on a suite of cognitive tests.

Related chapters from BN: Chapter 17: Learning and Memory; Chapter 12: Sex: Evolutionary, Hormonal, and Neural Bases
Related chapters from MM:Chapter 13: Memory and Learning; Chapter 8: Hormones and Sex
Link ID: 29132 - Posted: 02.06.2024

By Meeri Kim A woman’s menstrual cycle is driven by the ebb and flow of hormones that prepare the body for pregnancy. This symphony of hormones not only transforms the reproductive organs, but, according to recent research, also reshapes the brain. Live well every day with tips and guidance on food, fitness and mental health, delivered to your inbox every Thursday. Two studies released in October performed detailed brain scans of women at multiple points across the menstrual cycle, finding that the volume or thickness of certain regions change in sync with hormone levels. The areas of the brain highlighted by both studies are those in the limbic system, a group of brain structures that govern emotions, memory and behavior. “It’s like the brain being on a roller coaster every 28 days or so, depending on the length of the cycle,” said Erika Comasco, associate professor of women and children’s health at Uppsala University in Sweden, who was not involved in the research. “The importance of these studies is that they are building knowledge about the impact of these hormonal fluctuations on how the brain is structured.” “These brain changes may or may not alter the way we actually act, think and feel in our everyday lives. So the important next steps for the science are to put those pieces of the puzzle together,” said Adriene Beltz, associate professor of psychology at the University of Michigan, who was also not involved in the research. “Do the hormonal effects on brain structure influence how the brain works?” How hormones drive the menstrual cycle During a woman’s period, which marks the beginning of the menstrual cycle, hormones are at low levels. But they rise dramatically over a few weeks. Estrogen levels in the blood become eight times higher at ovulation around Day 14, while progesterone levels increase by 80-fold approximately seven days later. The production of follicle-stimulating hormone prompts the growth of an ovarian follicle into a mature egg, while a surge of luteinizing hormone triggers the release of the egg.

Related chapters from BN: Chapter 12: Sex: Evolutionary, Hormonal, and Neural Bases; Chapter 5: Hormones and the Brain
Related chapters from MM:Chapter 8: Hormones and Sex; Chapter 8: Hormones and Sex
Link ID: 29026 - Posted: 12.02.2023

Claudia López Lloreda The idea that the nervous system passes messages from one nerve cell to another only through synapses — the points where the cells link up end to end — is changing. Two studies show how messages can pass between cells over longer distances, through a ‘wireless’ nerve network in the worm Caenorhabditis elegans. Researchers had not appreciated the extent of this wireless communication, which happens when a molecule called a neuropeptide is released by one neuron and intercepted by another some distance away. The new studies, published in Nature1 and in Neuron2, map out the entire network of neuropeptide communication in a model organism for the first time. “We knew that these chemical connections existed, but this is probably the most comprehensive study in an entire nervous system,” says Gáspár Jékely, a neuroscientist at Heidelberg University in Germany who was not involved in the work. And what the research shows, he adds, is that “it’s not all about the synapses”. Researchers had previously worked out anatomical wiring maps — connectomes — showing how all the neurons in the fruit fly (Drosophila melanogaster) and in C. elegans are linked by their synapses. However, William Schafer, a neuroscientist at the MRC Laboratory of Molecular Biology in Cambridge, UK, wondered about the role of neuropeptides, which had been considered merely helpers in nervous-system messaging. “When I first started talking about this,” he says, “some people wondered, ‘is it all just kind of a soup’” where neuropeptides randomly float from one neuron to the next, “or can you really think about it like a network?” He and his colleagues analysed which neurons in the C. elegans nervous system expressed genes for certain neuropeptides and which ones expressed genes for the receptors of those neuropeptides. Using this data, the team predicted which pairs of nerve cells might be communicating wirelessly. On the basis of these results, the researchers generated a potential map of wireless connections in the worm, finding dense connectivity that looks very different from the anatomical wiring diagram of C. elegans. They published their findings in Neuron2 last week. © 2023 Springer Nature Limited

Related chapters from BN: Chapter 5: Hormones and the Brain; Chapter 7: Life-Span Development of the Brain and Behavior
Related chapters from MM:Chapter 8: Hormones and Sex; Chapter 13: Memory and Learning
Link ID: 29017 - Posted: 11.22.2023

By Bruce Bower Female chimps living in an East African forest experience menopause and then survive years, even decades, after becoming biologically unable to reproduce. The apes are the first known examples of wild, nonhuman primates to go through the fertility-squelching hormonal changes and live well beyond their reproductive years. The finding raises new questions about how menopause evolved, UCLA evolutionary anthropologist Brian Wood and colleagues conclude in the Oct. 27 Science. Until now, females who experience menopause and keep living for years have been documented only in humans and five whale species. It’s unclear what evolutionary benefit exists to explain such longevity past the point of being able to give birth and pass on one’s genes. Although evolutionary explanations for menopause remain debatable, the new finding reflects an especially close genetic relationship between humans and chimps, Wood says. “Both [species] are more predisposed to post-reproductive survival than other great apes.” Some evidence suggests that female fertility ends at similar ages in humans and chimps (Pan troglodytes) if our ape relatives live long enough, says anthropologist Kristen Hawkes of the University of Utah in Salt Lake City. But in other studies, female chimps, such as those studied by Jane Goodall at Tanzania’s Gombe National Park starting in 1960, aged quickly and often died in their early 30s, usually while still having menstrual cycles, she says. “What’s surprising [in Wood’s study] is so many females living so long after menopause,” Hawkes says. © Society for Science & the Public 2000–2023.

Related chapters from BN: Chapter 12: Sex: Evolutionary, Hormonal, and Neural Bases; Chapter 6: Evolution of the Brain and Behavior
Related chapters from MM:Chapter 8: Hormones and Sex
Link ID: 28975 - Posted: 10.28.2023

By Sandra G. Boodman Bridget Houser felt despairing. In the months before her 2018 wedding, Houser, who had never struggled with her weight, noticed that it inexplicably began to creep up. In response she doubled the length of her runs to eight miles, took back-to-back high intensity workout classes and often consumed only water, coffee and fruit during the day before a spartan, mostly vegetable, dinner. Yet no matter what Houser did, her weight stubbornly increased and her oval face grew round, a transformation that was glaringly obvious in comparison with her identical twin sister. Houser wondered whether the five pounds she gained despite her herculean effort was a corollary of other problems. For the previous two years she had battled a string of maladies: first daily headaches, then crippling anxiety, followed by insomnia, hair loss and acne, something she’d never endured as a teenager. “Stress was the universal explanation,” recalled Houser, a controller for a small business in Chicago. When doctors suggested that her upcoming marriage might be a cause of her problems, Houser considered, then rejected, the theory. It just didn’t jibe with her feelings. In early 2019, about six months after her wedding, Houser insisted that her doctors perform several tests. They ultimately revealed that her symptoms weren’t the result of stress or marital misgivings but of a serious illness that had been smoldering for years. After successful treatment followed by a long recovery Houser, now 34, feels far better than she did during those miserable years in her late 20s. “I wish I’d been nicer to myself and not blamed myself for what was going on,” she said.

Related chapters from BN: Chapter 5: Hormones and the Brain; Chapter 13: Homeostasis: Active Regulation of the Internal Environment
Related chapters from MM:Chapter 8: Hormones and Sex; Chapter 9: Homeostasis: Active Regulation of the Internal Environment
Link ID: 28951 - Posted: 10.10.2023

Heidi Ledford When Naomi Rance first started studying menopause and the brain, she pretty much had the field to herself. And what she was discovering surprised her. In studies of post-mortem brains, she had found neurons in a region called the hypothalamus that roughly doubled in size in women after menopause1. “This was changing so much in postmenopausal women,” says Rance, a neuropathologist at the University of Arizona in Tucson. “It had to be important.” This was the 1990s, and few other researchers were interested. Rance forged ahead on her own, painstakingly unravelling what the neurons were doing and finessing a way to study menopause symptoms in rats by tracking tiny temperature changes in their tails as a measure of hot flushes, a common symptom of menopause that is thought to be triggered in the hypothalamus. Thirty years later, a drug called fezolinetant, based on Rance’s discoveries, is being evaluated by the US Food and Drug Administration, with an approval decision expected in the first half of this year. If approved, fezolinetant could be a landmark: the first non-hormonal therapy to treat the source of hot flushes, a symptom that has become nearly synonymous with menopause and one that is experienced by about 80% of women going through the transition. (This article uses ‘women’ to describe people who experience menopause, while recognizing that not all people who identify as women go through menopause, and not all people who go through menopause identify as women.) Rance and others in the field, fezolinetant’s progress to this point is a sign that research into the causes and effects of menopausal symptoms is finally being taken seriously. In the next few years, the global number of postmenopausal women is expected to surpass one billion. But many women still struggle to access care related to menopause, and research into how best to manage such symptoms has lagged behind. That is slowly changing. Armed with improved animal models and a growing literature on the effects of existing treatments, more researchers are coming into the field to fill that gap. © 2023 Springer Nature Limited

Related chapters from BN: Chapter 17: Learning and Memory; Chapter 12: Sex: Evolutionary, Hormonal, and Neural Bases
Related chapters from MM:Chapter 13: Memory and Learning; Chapter 8: Hormones and Sex
Link ID: 28778 - Posted: 05.10.2023

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

Related chapters from BN: Chapter 12: Sex: Evolutionary, Hormonal, and Neural Bases; Chapter 5: Hormones and the Brain
Related chapters from MM:Chapter 8: Hormones and Sex; Chapter 8: Hormones and Sex
Link ID: 28658 - Posted: 02.08.2023

By Bonnie Berkowitz and  William Neff Creating a physique that can win at the highest level of professional bodybuilding requires superhuman self-discipline, intense training and genetic good fortune. Increasingly, say the people familiar with the culture and its consequences, it cannot be done without illicit drugs and a willingness to push a body to — or past — its limits. More than a dozen scientists, trainers, judges and competitors interviewed for this report said that just earning a pro card, an amateur’s ticket to the pro ranks, is very difficult without anabolic steroids. Winning a marquee title drug-free? Several people laughed at the question. “Impossible,” said Harrison Pope, one of the country’s leading anabolic-steroid researchers. The behemoths who win the best-known and most lucrative titles barely resemble the iconic, classically muscled champions of the past, such as Arnold Schwarzenegger, who won the sport’s premiere title, Mr. Olympia, seven times between 1970 and 1980. “Arnold Schwarzenegger would not win today,” said Brad Schoenfeld, a professor at Lehman College in New York and author of several books on bodybuilding and muscle growth. “He would not even get a pro card.” Although bodybuilders spend years lifting weights and honing each muscle, they don’t need to demonstrate strength for the judges beyond the ability to hold poses onstage. They only need to look strong. Some competitors — and a growing legion of young, mostly male admirers — chase that look by diving into a reckless pharmacological game of whack-a-mole that insiders say has grown more intense and dangerous as sheer size has trumped the “Greek god” ideal of previous generations.

Related chapters from BN: Chapter 12: Sex: Evolutionary, Hormonal, and Neural Bases; Chapter 5: Hormones and the Brain
Related chapters from MM:Chapter 8: Hormones and Sex; Chapter 8: Hormones and Sex
Link ID: 28588 - Posted: 12.10.2022

By Ingrid Wickelgren  Science has largely neglected pregnancy’s effect on the brain, even though it involves dramatic surges in steroid hormones, which are known to alter the organ. A decade ago neuroscientist Elseline Hoekzema, then a young postdoctoral fellow thinking about having her first child, and two of her female colleagues set out to bridge the knowledge gap. “There’s this enormous event involving such strong hormone changes,” says Hoekzema, now at Amsterdam University Medical Center. “It’s really weird that so little was known about this.” Their initial study, published in 2016, revealed for the first time that pregnancy produced significant structural changes in a woman’s brain that endured for at least two years after birth. Now in a new seven-year study, Hoekzema and her colleagues have seen the same structural changes in different women and have shown that pregnancy also alters the function of a key brain network involved in self-reflection. According to the work, which appeared on Nov. 22 in Nature Communications, the brain changes correlate with a mother’s enhanced bonding with her baby. The findings were derived from examining the female participants’ physiology and using questionnaires to assess their behavior and mental state. And for the first time in humans, the researchers found strong evidence that female hormones are behind it all. The biggest changes occur in a brain network that is active when the brain is idling—that is, when it is not engaged in any particular task—suggesting that pregnancy alters the organ’s baseline state. “[The researchers] are seeing these functional connectivity changes even at rest,” says Jodi Pawluski, a neuroscientist at the University of Rennes 1 in France, who studies the maternal brain and perinatal mental illness but was not involved in the study. “That speaks to the significance of this stage in a birthing person’s life and how it really is transformative in the brain.”

Related chapters from BN: Chapter 12: Sex: Evolutionary, Hormonal, and Neural Bases; Chapter 5: Hormones and the Brain
Related chapters from MM:Chapter 8: Hormones and Sex; Chapter 8: Hormones and Sex
Link ID: 28566 - Posted: 11.23.2022

Nicola Davis Regular doses of a hormone may help to boost cognitive skills in people with Down’s syndrome, a pilot study has suggested. Researchers fitted seven men who have Down’s syndrome with a pump that provided a dose of GnRH, a gonadotropin-releasing hormone, every two hours for six months. Six out of the seven men showed moderate cognitive improvements after the treatment, including in attention and being able to understand instructions, compared with a control group who were not given the hormone. However, experts raised concerns about the methods used in the study, urging caution over the findings. The team behind the work said brain scans of the participants, who were aged between 20 and 37, given the hormone suggest they underwent changes in neural connectivity in areas involved in cognition. “[People] with Down’s syndrome have cognitive decline which starts in the 30s,” said Prof Nelly Pitteloud, co-author of the study from the University of Lausanne. “I think if we can delay that, this would be great, if the therapy is well tolerated [and] without side effects.” Writing in the journal Science, Pitteloud and colleagues said they previously found mice with an extra copy of chromosome 16 experienced an age-related decline in cognition and sense of smell, similar to that seen in people with Down’s syndrome – who have an extra copy of chromosome 21. In a series of experiments, the team found regular doses of gonadotropin-releasing hormone boosted both the sense of smell and cognitive performance of these mice. Pitteloud said no side effects were seen in the participants and that the hormone is already used to induce puberty in patients with certain disorders. “I think these data are of course very exciting, but we have to remain cautious,” said Pitteloud. She said larger, randomised control studies are now needed to confirm that the improvements were not driven by patients becoming less stressed during assessments and thus performing better. Prof Michael Thomas of Birkbeck, University of London, who studies cognitive development across the lifespan in Down’s syndrome, said the results were exciting. “For parents, this is good news: interventions can still yield benefits across the lifespan,” he said, although he noted it is not clear how applicable the hormone therapy would be for children. © 2022 Guardian News & Media Limited

Related chapters from BN: Chapter 7: Life-Span Development of the Brain and Behavior; Chapter 12: Sex: Evolutionary, Hormonal, and Neural Bases
Related chapters from MM:Chapter 13: Memory and Learning; Chapter 8: Hormones and Sex
Link ID: 28462 - Posted: 09.03.2022

By Azeen Ghorayshi Marcia Herman-Giddens first realized something was changing in young girls in the late 1980s, while she was serving as the director for the child abuse team at Duke University Medical Center in Durham, N.C. During evaluations of girls who had been abused, Dr. Herman-Giddens noticed that many of them had started developing breasts at ages as young as 6 or 7. “That did not seem right,” said Dr. Herman-Giddens, who is now an adjunct professor at the University of North Carolina Gillings School of Global Public Health. She wondered whether girls with early breast development were more likely to be sexually abused, but she could not find any data keeping track of puberty onset in girls in the United States. So she decided to collect it herself. A decade later, she published a study of more than 17,000 girls who underwent physical examinations at pediatricians’ offices across the country. The numbers revealed that, on average, girls in the mid-1990s had started to develop breasts — typically the first sign of puberty — around age 10, more than a year earlier than previously recorded. The decline was even more striking in Black girls, who had begun developing breasts, on average, at age 9. The medical community was shocked by the findings, and many were doubtful about a dramatic new trend spotted by an unknown physician assistant, Dr. Herman-Giddens recalled. “They were blindsided,” she said. But the study turned out to be a watershed in the medical understanding of puberty. Studies in the decades since have confirmed, in dozens of countries, that the age of puberty in girls has dropped by about three months per decade since the 1970s. A similar pattern, though less extreme, has been observed in boys. Although it is difficult to tease apart cause and effect, earlier puberty may have harmful impacts, especially for girls. Girls who go through puberty early are at a higher risk of depression, anxiety, substance abuse and other psychological problems, compared with peers who hit puberty later. Girls who get their periods earlier may also be at a higher risk of developing breast or uterine cancer in adulthood. © 2022 The New York Times Company

Related chapters from BN: Chapter 7: Life-Span Development of the Brain and Behavior; Chapter 12: Sex: Evolutionary, Hormonal, and Neural Bases
Related chapters from MM:Chapter 13: Memory and Learning; Chapter 8: Hormones and Sex
Link ID: 28332 - Posted: 05.21.2022

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

Related chapters from BN: Chapter 12: Sex: Evolutionary, Hormonal, and Neural Bases; Chapter 5: Hormones and the Brain
Related chapters from MM:Chapter 8: Hormones and Sex; Chapter 8: Hormones and Sex
Link ID: 28298 - Posted: 04.23.2022

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

Related chapters from BN: Chapter 5: Hormones and the Brain; Chapter 7: Life-Span Development of the Brain and Behavior
Related chapters from MM:Chapter 8: Hormones and Sex; Chapter 13: Memory and Learning
Link ID: 28143 - Posted: 01.08.2022

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

Related chapters from BN: Chapter 12: Sex: Evolutionary, Hormonal, and Neural Bases; Chapter 18: Attention and Higher Cognition
Related chapters from MM:Chapter 8: Hormones and Sex; Chapter 14: Attention and Higher Cognition
Link ID: 28033 - Posted: 10.13.2021

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

Related chapters from BN: Chapter 5: Hormones and the Brain; Chapter 15: Emotions, Aggression, and Stress
Related chapters from MM:Chapter 8: Hormones and Sex; Chapter 11: Emotions, Aggression, and Stress
Link ID: 27981 - Posted: 09.08.2021

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

Related chapters from BN: Chapter 12: Sex: Evolutionary, Hormonal, and Neural Bases; Chapter 5: Hormones and the Brain
Related chapters from MM:Chapter 8: Hormones and Sex; Chapter 8: Hormones and Sex
Link ID: 27917 - Posted: 07.21.2021

By Sally Satel For over a half-century, steroid drugs have been a mainstay of medical care, widely used to treat inflammatory illness such as asthma, skin conditions and autoimmune diseases. Less is known about their dramatic and sometimes frightening long-term effects on mood, personality and thinking. I took steroids years ago, and the side effects changed my life. Steroid medications mimic a natural hormone in the body called glucocorticoid, which suppresses immune system processes that trigger inflammation, the sources of many autoimmune and chronic disease. In 1948, glucocorticoid was first used for a chronic inflammatory disease, rheumatoid arthritis, which causes joint deformity and chronic pain. Two years later, the American physician behind the breakthrough therapy was one of the winners of the Nobel Prize. Steroids have been prescribed for many other conditions since then. One steroid, dexamethasone, has been used for people with severe cases of covid-19 and President Trump was given it when he was hospitalized for the disease in October. My story starts in 1977. I was finishing my senior year as a biology major at Cornell University when I was diagnosed with Crohn’s disease, a form of inflammatory disease in which the body’s immune system attacks the gastrointestinal tract. I had a relatively mild case — transient pain, causing me to rush to the nearest ladies’ room, and find some blood in the bowl — and so I was able to finish my final year on time and begin a PhD program in evolutionary biology that summer. My predoctoral project entailed measuring the jaw muscles of tadpoles using jewelers’ tools and a dissecting microscope. Within weeks, though, I had a “flare” in the parlance of gastroenterology — I felt weak and was having increased bouts of blood-streaked diarrhea. In mid-October, I spent five days at the hospital where my symptoms resolved on a daily regimen of 60 mg of the potent steroid prednisone. I was discharged on 60 mg per day and felt fine for a week. But soon my brain began to feel like cotton wrapped in yards of gauze. I tried to study for an upcoming quiz but I couldn’t concentrate. © 1996-2020 The Washington Post

Related chapters from BN: Chapter 5: Hormones and the Brain
Related chapters from MM:Chapter 8: Hormones and Sex
Link ID: 27609 - Posted: 12.07.2020

By Lisa Sanders, M.D. The waiter had barely put the plate in front of her when the 46-year-old woman felt the color drain from her face. She was in Fresno, Calif., on a work trip and had come to a restaurant to meet an old friend for dinner. But all of a sudden her stomach dropped — the way it might on a roller-coaster ride. A sudden coolness on her face told her she’d broken out in a sweat. She felt dizzy and a little confused. She saw the alarmed face of her friend and knew she looked as bad as she felt. She excused herself and carefully made her way to the bathroom. She sat in front of the vanity and supported her head on her arms. There was the now-familiar stabbing pain in her stomach. She wasn’t sure how long she stayed like that. Was it 10 minutes? 15? At last she felt as if she could get up. As she hurried to meet her friend at the entrance, she felt the contents of her stomach surging upward. She covered her mouth as vomit shot between her fingers. She lowered her head and bolted through the doorway, trying not to see the horrified faces of the diners. In the parking lot, the rush of stomach contents continued until she was completely empty. Exhausted, she sank into the seat of her friend’s car. She was too sick to go back to her hotel, her friend said. Instead the friend would take her to her house, until she felt better. The next thing the woman remembered was that she was sitting on the floor of her friend’s shower, hot water pounding her back. When she could, she crawled into bed. She slept until late the next morning. She thanked her friend, canceled her morning meetings and later that day headed home to Stockton, Calif. © 2020 The New York Times Company

Related chapters from BN: Chapter 5: Hormones and the Brain; Chapter 13: Homeostasis: Active Regulation of the Internal Environment
Related chapters from MM:Chapter 8: Hormones and Sex; Chapter 9: Homeostasis: Active Regulation of the Internal Environment
Link ID: 27498 - Posted: 09.30.2020

David Cox Gérard Karsenty was a young scientist trying to make a name for himself in the early 1990s when he first stumbled upon a finding that would go on to transform our understanding of bone, and the role it plays in our body. Karsenty had become interested in osteocalcin, one of the most abundant proteins in bone. He suspected that it played a crucial role in bone remodelling – the process by which our bones continuously remove and create new tissue – which enables us to grow during childhood and adolescence, and also recover from injuries. Intending to study this, he conducted a genetic knockout experiment, removing the gene responsible for osteocalcin from mice. However to his dismay, his mutant mice did not appear to have any obvious bone defects at all. “For him, it was initially a total failure,” says Mathieu Ferron, a former colleague of Karsenty who now heads a research lab studying bone biology at IRCM in Montreal. “In those days it was super-expensive to do modification in the mouse genome.” But then Karsenty noticed something unexpected. While their bones had developed normally, the mice appeared to be both noticeably fat and cognitively impaired. “Mice that don’t have osteocalcin have increased circulating glucose, and they tend to look a bit stupid,” says Ferron. “It may sound silly to say this, but they don’t learn very well, they appear kind of depressed. But it took Karsenty and his team some time to understand how a protein in bone could be affecting these functions. They were initially a bit surprised and terrified as it didn’t really make any sense to them.” © 2020 Read It Later, Inc.

Related chapters from BN: Chapter 5: Hormones and the Brain; Chapter 17: Learning and Memory
Related chapters from MM:Chapter 8: Hormones and Sex; Chapter 13: Memory and Learning
Link ID: 27473 - Posted: 09.16.2020

by Chloe Williams A new wireless device activates a mouse’s neurons as it navigates a cage with food, hiding places and other mice, allowing researchers to study social behavior in a realistic environment1. Experiments using this setup suggest that oxytocin has distinct effects in different contexts — which may be particularly important as researchers explore the hormone’s value as a potential treatment for autism. The device makes use of optogenetics, a technique in which researchers use pulses of light to activate or silence neurons. Autism researchers have used the approach to manipulate neural circuits in mice, but traditional optogenetic devices involve a fiber-optic cable, which tethers the animal and interferes with social interactions. Other wireless devices have been able to activate neurons without a tether, but researchers have mostly used them to study social behavior involving just two mice interacting for only about 15 minutes in an otherwise empty cage — a scenario that fails to capture a full range of mouse behaviors2. The new wireless device, powered by two watch batteries, consists of a light-emitting diode attached to an optical fiber that is implanted into the brain. It has an on-off switch that allows researchers to control it remotely using a magnet placed inside the cage. Using this setup, researchers can modulate brain activity in a group of mice as they roam for days through a cage that has hiding places, platforms, a nest, food and water. The device’s designers tested it in mice engineered to express light-sensitive proteins in part of the hypothalamus. This region produces the hormone oxytocin, generally thought to reduce aggression and enhance social bonds. When delivered as a nasal spray, it improves social skills in some people with autism. © 2020 Simons Foundation

Related chapters from BN: Chapter 5: Hormones and the Brain; Chapter 12: Sex: Evolutionary, Hormonal, and Neural Bases
Related chapters from MM:Chapter 8: Hormones and Sex; Chapter 8: Hormones and Sex
Link ID: 27369 - Posted: 07.16.2020