Chapter 5. Hormones and the Brain

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Researchers at the University of Waterloo say they have developed a new, "kid-friendly" way of diagnosing autism in young children. It uses infrared technology to read the way a child's eyes move as they process the features of a person's face. "A neuro-typical child will spend a whole lot more time looking at the person's — or the face's — eye," Anita Layton, a professor of applied mathematics, pharmacy and biology, told CBC Kitchener-Waterloo. "A [child with autism] will look at the mouth a lot more." Layton and her team developed the technique by showing a group of 40 children 44 photographs on a screen connected to their eye-tracking device. The children were all around 5 years old. Seventeen had been previously diagnosed as on the spectrum, the other 23 were considered neuro-typical. The difference in eye tracking has been well documented, Layton said. Her team found a way to turn that difference into a diagnostic tool that works well for young children and even non-verbal kids on the more complicated end of the spectrum. Right now, the two most popular ways of diagnosing Autism Spectrum Disorder are by having the child or parent fill out a comprehensive questionnaire, or have the child evaluated by a psychologist. "It's not easy for a child. Imagine a four or five-year-old child, neuro-typical or [autistic] to sit there for a long time, to answer your questions. That simply is no fun for a kid," Layton said. The eye-tracking test, on the other hand, can be done in just a few minutes. ©2019 CBC/Radio-Canada

Keyword: Autism; Vision
Link ID: 26419 - Posted: 07.15.2019

Bethany Brookshire When researchers release a new finding about the brain, it’s often mice or rats who have run the mazes and taken the tests for science. People might wonder: Are rodents good substitutes for humans? Maybe for men, but what about women? That’s less likely, because most neuroscience experiments don’t use female rodents — a fact one scientist says comes from outdated ideas that should go into the scientific dustbin. For years, many scientists have dismissed female rodents as too variable to use in the lab, with tricky hormone surges that can affect behavior and compromise study results. In 2009, male lab mammals in neuroscience studies outnumbered females 5.5 to 1, according to a 2011 study in Neuroscience & Biobehavioral Reviews. “The idea that women are primarily driven by ovarian hormones [was] a narrative put in place intentionally in the Victorian era,” says Rebecca Shansky, a neuroscientist at Northeastern University in Boston. “That has also infiltrated the way we think about female animals” in science. Male animals can be just as “hormonal” as their female counterparts, Shansky argues in an essay published May 31 in Science, and it’s time that both sexes got equal attention in the lab. Here are five things to know about the issue of sex in the study of rodent brains. In humans, reproductive hormones such as estrogen and progesterone ebb and flow over a roughly 28-day cycle. In rodents, that cycle is compressed to four or five days. Estrogen or progesterone levels on one day could be up to four times as much as on the day before. |© Society for Science & the Public 2000 - 2019

Keyword: Sexual Behavior; Hormones & Behavior
Link ID: 26342 - Posted: 06.20.2019

By Lisa Feldman Barrett My husband found me sobbing on the kitchen floor. My job was in upheaval, my travel schedule was grueling, and with two hours left before my next departure, I’d discovered that my laptop was dead. This was the moment my husband walked in to console me, and in an impressive feat of bad timing, he also asked whether I was premenstrual. I went from sobbing to supernova in about two seconds, enraged by his presumption that surging female hormones were responsible for my emotional distress. The only thing that saved him was that, a few days later, I discovered that he’d been right. I am a scientist who studies the nature of emotions. For most of my scientific career, I didn’t believe that women systematically had emotional eruptions right before their period, even though I experienced them occasionally. Studies suggested that women who believe in premenstrual syndrome, when asked about it in retrospect, tend to misremember the symptoms as more severe than they were. The evidence for PMS overall was inconsistent. Certainly, I knew of no neurological reason that women should feel, just before their period, that the world was crashing down on them. My doubt was also political in nature. During my clinical internship over 20 years ago, my boss, a psychiatrist, asked me to research how PMS prevents women from thinking clearly. I told him he was a relic of the Stone Age. Women were as consistently clearheaded as men, if not more so. But recently, a researcher in my lab, Joe Andreano, an expert on female hormones, showed me some surprising data. As a woman’s levels of progesterone and estrogen vary, so does the connectivity between two brain networks: the default mode network and the salience network. These networks play key roles in creating your emotional life. If I hadn’t seen the data with my own eyes, I wouldn’t have believed it. © 2019 The New York Times Company

Keyword: Hormones & Behavior; Sexual Behavior
Link ID: 26317 - Posted: 06.10.2019

By Mitch Leslie If papers published in the past 6 months are right, a single number is enough to show whether people are likely to suffer a premature heart attack, land first authorship on published papers, become dependent on alcohol, or put on fat around the middle. That magic number is the ratio between the lengths of the second and fourth fingers, known as the 2D:4D ratio. It tends to be lower in men—meaning their fourth fingers tend to be longer than their second—than in women. Researchers who believe in its predictive power say it reflects a fetus's exposure to testosterone and other hormones that guide development, including that of the brain. The idea that the lengths of human fingers reveal so much stems from the work of evolutionary biologist John Manning, now at Swansea University in the United Kingdom. But the field he inspired has ballooned beyond what he could have imagined. More than 1400 papers in just over 20 years have linked the finger ratio to attributes such as personality, cognitive abilities, and sexual orientation as well as to risk of illnesses such as cardiovascular disease, cancer, and amyotrophic lateral sclerosis. Researchers have even tried to use ratios gleaned from stenciled handprints on cave walls to determine whether the artists behind ancient paintings were men or women. But the notion has also riled plenty of critics, who argue that researchers who rely on the 2D:4D comparison have been seduced by a simplistic, faulty measure. Some doubters contend that the difference in ratios between the sexes is an illusion resulting from men's larger hands or that the measure itself is statistically problematic. "I'm skeptical about every single finding involving that ratio," says physiologist and biostatistician Douglas Curran-Everett of National Jewish Health in Denver. © 2019 American Association for the Advancement of Science

Keyword: Sexual Behavior; Hormones & Behavior
Link ID: 26311 - Posted: 06.07.2019

By Aiyana Bailin To my dismay, Simon Baron-Cohen’s recent article “The Concept of Neurodiversity is Dividing the Autism Community” perpetuates a common misunderstanding of the neurodiversity movement: that it views autism as a difference but not a disability. Baron-Cohen presents the issue as one of opposing sides: the medical model, which sees autism as a set of symptoms and deficits to be cured or treated, and the neurodiversity model, which he believes ignores any disabling aspects of autism. Unfortunately, this confuses the neurodiversity movement with the social model of disability, and it is an incomplete understanding of the social model at that. Before I go into details, let me summarize what the neurodiversity movement does believe: Autism and other neurological variations (learning disabilities, ADHD, etc.) may be disabilities, but they are not flaws. People with neurological differences are not broken or incomplete versions of normal people. Disability, no matter how profound, does not diminish personhood. People with atypical brains are fully human, with inalienable human rights, just like everyone else. People with disabilities can live rich, meaningful lives. Neurological variations are a vital part of humanity, as much as variations in size, shape, skin color and personality. None of us has the right (or the wisdom) to try and improve upon our species by deciding which characteristics to keep and which to discard. Every person is valuable. Disability is a complicated thing. Often, it’s defined more by society’s expectations than by individual conditions. Not always, but often. © 2019 Scientific American

Keyword: Autism
Link ID: 26310 - Posted: 06.07.2019

By Marisa Iati A bill in Alabama awaiting the governor’s signature would require people convicted of certain sex offenses to undergo “chemical castration” as a condition of parole — a requirement meant to keep perpetrators from committing similar crimes. The proposed law, passed by the state legislature, says a judge must order anyone convicted of a sex offense involving a child under the age of 13 to start receiving testosterone-inhibiting medication a month before their release from prison. Most offenders would have to pay for their treatment, which would be administered by the Department of Public Health, until a judge decides the medication is no longer necessary. Under the proposed law, a judge — and not a doctor — would tell the offender about the effects of the treatment. An offender could choose to stop getting the medication and return to prison to serve the remainder of their term. Anyone who stopped receiving the castration treatment without approval would be considered guilty of a Class C felony, punishable under Alabama law by up to 10 years in prison and a fine of up to $15,000. “Chemical castration” is a misnomer, as the process leaves the testes intact, can be reversed and does not prevent a man from reproducing. It does not guarantee a man’s sexual urge will be eliminated. (There’s no consensus on whether chemical castration would be effective for women.) © 1996-2019 The Washington Post

Keyword: Sexual Behavior; Aggression
Link ID: 26304 - Posted: 06.06.2019

by C.L. Lynch Everyone knows that autism is a spectrum. People bring it up all the time. “My son is on the severe end of the autism spectrum.” “We’re all a little autistic– it’s a spectrum.” “I’m not autistic but I’m definitely ‘on the spectrum.'” If only people knew what a spectrum is… because they are talking about autism all wrong. Let’s use the visible spectrum as an example. As you can see, the various parts of the spectrum are noticeably different from each other. Blue looks very different from red, but they are both on the visible light spectrum. Red is not “more blue” than blue is. Red is not “more spectrum” than blue is. When people discuss colours, they don’t talk about how “far along” the spectrum a colour is. They don’t say “my walls are on the high end of the spectrum” or “I look best in colours that are on the low end of the spectrum.” But when people talk about autism they talk as if it were a gradient, not a spectrum at all. People think you can be “a little autistic” or “extremely autistic,” the way a paint colour could be a little red or extremely red. An image of a colour gradient moving from white to red. The lightest zone is labelled How people think the spectrum looks But autism isn’t that simple. Autism isn’t a set of defined symptoms that collectively worsen as you move “up” the spectrum.

Keyword: Autism
Link ID: 26254 - Posted: 05.21.2019

Ruth Williams Sequencing the nuclear RNA of more than 100,000 individual postmortem brain cells from people with and without autism spectrum disorder indicates the types of genes dysregulated in the condition and the types of cells in which such dysregulation occurs. The results, reported in Science today (May 16), help narrow the focus of future ASD studies to the most likely molecular and cellular anomalies, say researchers. “It’s using the latest technology, it’s looking at the single cell level, and it validates and extends previous observations,” says autism researcher Daniel Geschwind of the University of California, Los Angeles, who was not involved in the research. “It takes the previous work and brings it to a level of resolution that we didn’t have before.” “This was an experiment that needed to be done,” adds geneticist Stephan Sanders of the University of California, San Francisco, writing in an email to The Scientist. “At the tissue level, it broadly replicates previous data in autism. Then, [it] provides a first look at which cell types are responsible for the differences.” ASD, which currently affects somewhere around 1 in 60 children in the United States, includes a broad range of conditions that are characterized by an impaired ability to communicate and interact socially. The heterogeneous nature of ASD has made studies of its molecular pathology difficult. Nevertheless, gene expression studies carried out on postmortem brain tissue from ASD patients have pointed to commonly affected pathways, including synapse function, says Dmitry Velmeshev, an author of the study and postdoc in the lab of neurologist Arnold Kriegstein, also an author. © 1986–2019 The Scientist

Keyword: Autism
Link ID: 26245 - Posted: 05.18.2019

By Jessica Wright, Clinicians can reliably diagnose autism in some toddlers roughly two years earlier than the typical age of diagnosis, a new study suggests. The researchers assessed more than 1,200 toddlers for autism at least twice using standard diagnostic tools. They diagnosed roughly one in three with the condition by age 2; 84 percent of these toddlers retained the label at their last visit, which was at age 3 on average. The finding suggests clinicians should take autism traits in toddlers seriously, says co-lead researcher Karen Pierce, professor of neurosciences at the University of California, San Diego. “If children meet criteria and they do show signs and symptoms, don’t wait; let’s get them the help and the treatment that they need,” Pierce says. Experts are divided on whether autism can reliably be diagnosed before age 3. The American Academy of Pediatrics recommends screening for autism starting at 18 months. However, the U.S. Preventive Services Task Force—a government panel that makes recommendations about preventive medicine—has said there is insufficient evidence to recommend universal screening before 3. The new study suggests that early screening and diagnosis may benefit some proportion of children: It indicates that some toddlers are likely to have clear enough signs of autism to warrant a diagnosis before 2 years of age, says Zachary Warren, associate professor of pediatrics, psychiatry and behavioral sciences at Vanderbilt University in Nashville, Tennessee. “The study shows that well-trained, expert teams evaluating young kids with autism are able to pick up concerns at fairly young ages for some kids,” says Warren, who was not involved in the work. “It’s an interesting and creative approach to understanding screening and diagnosis.” © 2019 Scientific American

Keyword: Autism
Link ID: 26243 - Posted: 05.17.2019

By Nicholette Zeliadt, Two drugs that alter the activity of the hormone vasopressin seem to improve social communication in people with autism. The findings come from two independent clinical trials published today in Science Translational Medicine. The results are encouraging, but some experts urge caution, saying the methods used to assess the drugs were not designed for that purpose. Vasopressin is related to oxytocin, a hormone thought to govern social bonding. But vasopressin’s link to autism is far from simple: There’s evidence implicating both too little and too much of the hormone in people with the condition. Advertisement The two drugs also target vasopressin in opposite ways. One of them, balovaptan, blocks a receptor for vasopressin in the brain and dampens the hormone’s activity. The other is a nasal spray containing vasopressin. Despite their opposing modes of action, both drugs appear to boost social function in autistic people; neither has serious side effects. The findings are noteworthy because no drugs are available to treat autism’s core traits, says Eric Hollander, professor of psychiatry and behavioral sciences at Albert Einstein College of Medicine in New York, who was not involved in either study. “These two studies provide important information that the vasopressin or vasopressin and oxytocin systems are important in social communication,” he says. “Different agents affecting these systems may ultimately be helpful in terms of new treatments for autism.” © 2019 Scientific American

Keyword: Autism; Hormones & Behavior
Link ID: 26202 - Posted: 05.03.2019

By Kelly Servick Many people with autism have trouble making eye contact, reading the emotions in other faces, and sharing affection. And no drugs are approved to treat such social impairments. Now, results from a small academic clinical trial suggest boosting levels of vasopressin—a hormone active in the brain that’s known to promote bonding in many animals—can improve social deficits in children with autism. But in a confusing twist, a larger, company-sponsored trial that took the reverse approach, tamping down vasopressin’s effects, also found some improvements in adults with autism. “I’ve never seen this before,” Kevin Pelphrey, a neuroscientist who studies autism at the University of Virginia in Charlottesville, says of the conflicting results. He and others say the vasopressin-blocking approach doesn’t have much support from previous animal research. The new study showed some benefits but failed to meet the main endpoint set out by investigators. Still, he says, both studies suggest vasopressin’s signaling in the brain plays a key role in autism and “give me a lot of renewed excitement” for treating the condition. Though vasopressin seems to stimulate social bonding in animals, the hormone’s activity in the brain isn’t fully understood, and its effects vary by species and context. Blocking its activity in the brains of some rodents prevents them from forming an attraction to a mate. But in a species of asocial hamster, injecting it into a male’s brain seems to stimulate aggression. © 2019 American Association for the Advancement of Science.

Keyword: Autism; Hormones & Behavior
Link ID: 26197 - Posted: 05.02.2019

By Gina Kolata The Court of Arbitration for Sport in Zurich has ruled that women with very high testosterone levels — far above the normal range — cannot compete against other women in races from 400 meters to one mile unless they take drugs to suppress production of the hormone. The ruling prevents Caster Semenya, 28, an elite runner and Olympic champion from South Africa, from competing in those races because her testosterone levels are naturally very high. She had challenged attempts to disqualify her from racing as a woman. The science underpinning that decision is complicated, raising difficult questions about biology, fairness and gender identity. What is testosterone? Where does it come from in women? It’s a hormone, an androgen, that has a variety of effects on the body. Women and men produce testosterone, but women don’t make nearly as much In men, high levels of testosterone are made by the testes. Much lower levels are produced in the adrenal glands, which rest above the kidneys. Women also make testosterone in their adrenal glands, and in their ovaries. But testes produce much more: Testosterone levels in men are 295 to 1,150 nanograms per deciliter of blood, while the levels in the women are 12 to 61 nanograms per deciliter of blood. Testosterone “builds muscle,” said Dr. Benjamin D. Levine, who studies sex differences in athletic performance at the University of Texas Southwestern Medical Center. “It builds skeletal muscle, it builds cardiac muscle. It increases the number of red blood cells.” The effects are seen whether the hormone is naturally present or introduced with drugs. In one of the most infamous examples, women who represented East Germany at the Olympic Games in the ’70s and ’80s achieved astounding success after they were unknowingly doped with anabolic steroids including testosterone. “The science is quite clear,” said Dr. Aaron Baggish of Massachusetts General Hospital, who is an expert on testosterone’s effects. “An androgenized body has a performance advantage.” © 2019 The New York Times Company

Keyword: Sexual Behavior; Hormones & Behavior
Link ID: 26196 - Posted: 05.02.2019

By Simon Baron-Cohen At the annual meeting of the International Society for Autism Research (INSAR) in Montreal, Canada, this week, one topic likely to be widely debated is the concept of neurodiversity. It is dividing the autism community, but it doesn’t have to. The term “neurodiversity” gained popular currency in recent years but was first used by Judy Singer, an Australian social scientist, herself autistic, and first appeared in print in the Atlantic in 1998. Neurodiversity is related to the more familiar concept of biodiversity, and both are respectful ways of thinking about our planet and our communities. The notion of neurodiversity is very compatible with the civil rights plea for minorities to be accorded dignity and acceptance, and not to be pathologized. And whilst the neurodiversity movement acknowledges that parents or autistic people may choose to try different interventions for specific symptoms that may be causing suffering, it challenges the default assumption that autism itself is a disease or disorder that needs to be eradicated, prevented, treated or cured. Many autistic people—especially those who have intact language and no learning difficulties such that they can self-advocate—have adopted the neurodiversity framework, coining the term “neurotypical” to describe the majority brain and seeing autism as an example of diversity in the set of all possible diverse brains, none of which is “normal” and all of which are simply different. © 2019 Scientific American

Keyword: Autism
Link ID: 26185 - Posted: 04.30.2019

Jessica Wright Sequencing can identify mutations linked to autism even before a child’s birth—especially in cases where doctors suspect problems, two new studies suggest. In the studies, scientists sequenced fetal DNA only when ultrasounds revealed atypical development of limbs or other organs, and they gave families only the results that seemed to explain those problems But there is a real risk that others might use the technique to test for mutations in any fetus—and to relay all the results to parents—without proper oversight, says Ronald Wapner, professor of obstetrics and gynecology at the Columbia Institute for Genomic Medicine, who led one of the studies. “Not everybody should be doing this; it should be in the hands of people that have expertise,” he says. Other types of analyses already detect mutations in a fetus: Some detect large DNA segments that are swapped between chromosomes, and others can pick up on missing or duplicated copies of DNA fragments. The new studies are among the first to scan for mutations across the fetal exome—essentially, the collection of genes in a genome. The field is fraught with ethical questions, including whether parents might choose to terminate a pregnancy based on the results. But the researchers note that most of the mutations they found pose serious health risks, which could be treated at birth or in utero. © 1986 - 2019 The Scientist

Keyword: Autism; Genes & Behavior
Link ID: 26168 - Posted: 04.24.2019

Nicola Davis Philandering men have unfaithfulness written all over their faces, according to research that suggests men and women are able to spot cheating chaps just by looking at them. Experts found men with more “masculine” faces were more likely to be thought to be unfaithful, and such men also self-reported more cheating or “poaching” of other men’s partners. However, they stressed the results were modest, and said people should be wary of deciding whether someone is a love rat based on impressions of facial features alone. The team said being suspicious of men with masculine features – such as a strong browridge, strong jaw and thinner lips – might have offered an evolutionary advantage, allowing heterosexual women to spot a flaky partner and men to recognise a potential rival who might seduce their partner or leave them raising someone else’s child. Previous research has suggested women are able to spot unfaithful men from their mugshot, with the masculinity of the man’s face a key factor in the judgment, while weaker effects have been found for men weighing up images of women. However, it was unclear whether people could also spot a philanderer of the same sex. Writing in the journal Royal Society Open Science, researchers described how they asked heterosexual white participants to judge the facial features of 189 white adults who had been photographed and taken part in previous research. Overall, 293 men and 472 women rated pictures of women, while 299 men and 452 women judged images of men, rating on a scale of one to 10 how likely they thought each person was to be unfaithful. © 2019 Guardian News & Media Limited

Keyword: Sexual Behavior; Evolution
Link ID: 26147 - Posted: 04.17.2019

By Denise Gellene Paul Greengard, an American neuroscientist whose 15-year quest to understand how brain cells communicate provided new insights into psychological diseases and earned him a Nobel Prize, and who used his entire $400,000 award to create an academic prize in memory of the mother he never knew, died on Saturday in Manhattan. He was 93. His death was confirmed by Rockefeller University, where he had worked since 1983. Dr. Greengard received the 2000 Nobel Prize in Physiology or Medicine with Dr. Arvid Carlsson of Sweden and Dr. Eric R. Kandel of the United States for independent discoveries related to the ways brain cells relay messages about movement, memory and mental states. Their discoveries offered new insights into disorders linked to errors in cell communication, such as Parkinson’s disease, schizophrenia, bipolar disorder and drug addiction. Dr. Greengard’s research described how cells react to dopamine, an important chemical messenger in the brain. His work provided the underlying science for many antipsychotic drugs, which modulate the strength of chemical signals in the brain. “Our work shows the details of how dopamine produces these effects — in other words, what’s wrong in these diseases and what can be done to correct them,” Dr. Greengard said. Dr. Greengard’s research extended from the late 1960s to the mid-1980s. For much of the period, his work was ignored. A majority of biologists believed brain cells communicated through the use of electrical signals. To them, the only thing that mattered was whether a cell fired off a signal. © 2019 The New York Times Company

Keyword: Drug Abuse; Schizophrenia
Link ID: 26139 - Posted: 04.15.2019

Wency Leung A new Canadian study on how the birth control pill affects a woman’s ability to think is the latest to address a decades-old knowledge gap researchers say needs to be fixed: How oral contraceptives impact the brain. The study aims to test the working memory of around 60 young women who use oral contraceptives, says researcher Laura Gravelsins, a PhD student with the Einstein Lab on cognitive neuroscience, gender and health at the University of Toronto. Gravelsins is among a number of researchers exploring an area that has historically been overlooked. Since the introduction of the pill in the 1960s, hormonal contraceptives – which contain estrogen, progestin, or a combination of both – have become a preferred option for many women. Yet, due, in part, to past assumptions that the brain operates separately from the rest of body and a general lack of research into women’s health, scientists are only now investigating how they may influence mood and cognition. Another area that needs exploration is how sex hormones, including those naturally produced by the body, influence developing brains. At the University of British Columbia, researchers are currently recruiting 300 girls, ages 13 to 15, to study what role sex hormones may play in their emotional development. “We need more research,” says Dr. Gillian Einstein, a professor of psychology at University of Toronto and the Wilfred and Joyce Posluns Chair in Women’s Brain Health and Aging. “Women should demand more research on this.”

Keyword: Hormones & Behavior; Sexual Behavior
Link ID: 26110 - Posted: 04.03.2019

By Tiffany Hsu Amazon has removed the online listings for two books that claim to contain cures for autism, a move that follows recent efforts by several social media sites to limit the availability of anti-vaccination and other pseudoscientific material. The books, “Healing the Symptoms Known as Autism” and “Fight Autism and Win,” which had previously been listed for sale in Amazon’s marketplace, were not available on Wednesday. The company confirmed that the listings had been removed, but declined to discuss why or whether similar books would be taken down in the future. Several such books were still listed on Wednesday. In an article published this week, Wired magazine noted that Amazon is crowded with titles promoting unproven treatments for autism that include “sex, yoga, camel milk, electroconvulsive therapy and veganism.” There is no cure for autism spectrum disorder, but there are medications that can help address associated symptoms like high energy levels and depression, according to the Centers for Disease Control and Prevention. The agency has found that as many as a third of parents with an autistic child have tried treatments that most pediatricians do not recommend, and that up to 10 percent may be using potentially dangerous tactics. The books that were listed on Amazon were both written more than five years ago and have together generated more than 600 customer reviews. “Healing the Symptoms Known as Autism” recommends that autistic children drink and bathe in chlorine dioxide, a compound often referred to as “Miracle Mineral Solution.” In 2010, the Food and Drug Administration described it as “a potent bleach used for stripping textiles and industrial water treatment” that “can cause nausea, vomiting, diarrhea, and symptoms of severe dehydration.” Representative Adam Schiff, Democrat of California, wrote an open letter this month to Jeff Bezos, Amazon’s chief executive, chiding the company about the failure of its algorithms to “distinguish quality information from misinformation or misleading information.” © 2019 The New York Times Company

Keyword: Autism; Neuroimmunology
Link ID: 26033 - Posted: 03.14.2019

Laura Sanders Young nerve cells derived from people with autism are precocious, growing bigger and developing sooner than cells taken from people without autism, a new study shows. The results, described January 7 in Nature Neuroscience, hint that in some cases nerve cells veer off course early in brain development to ultimately cause the disorder. As a proxy of brain growth, researchers led by Simon Schafer of the Salk Institute in La Jolla, Calif., transformed skin cells from people with and without autism into stem cells that then developed into nerve cells in the lab. Along the way, the scientists monitored the cells’ growth and the behavior of their genes. Compared with cells derived from five people without autism, cells from eight people with autism grew bigger, with longer and more elaborate branches, the researchers found. Three-dimensional balls called organoids made of the autism-derived cells were bulkier, too. In addition to this physical development, a group of genes important for brain development switched on sooner. Trouble in the autism-derived cells, however, actually began a bit earlier, just as the cells were on the cusp of becoming nerve cells. At the neural stem cell stage, certain spots of these cells’ chromatin — tightly packed genetic material — were more open and accessible than they should have been, an unfolding that can lead to abnormally active genes. The results show that open chromatin “can have major effects on neuronal development,” says neuroscientist David Amaral of the University of California, Davis. |© Society for Science & the Public 2000 - 2018.

Keyword: Autism
Link ID: 25856 - Posted: 01.11.2019

By Jane E. Brody Dr. Gayatri Devi’s patient, a 55-year-old former headmistress, had good reason to be distraught. The woman had a yearlong history of progressive memory loss and behavioral problems and was referred to Dr. Devi, a neurologist, with a possible diagnosis of frontotemporal dementia. As Dr. Devi recounted in the journal Obstetrics & Gynecology, the woman’s once prodigious memory had seriously deteriorated and she’d become increasingly irritable. She had difficulty organizing tasks, keeping track of belongings, setting goals, making plans and seeing them through. Yet the results of medical and neurological tests and brain scans were normal. Noting that the woman had gone through menopause a year earlier, Dr. Devi traced her symptoms to the decline in estrogen stimulation of the brain that occurs in all women at menopause with varying effects. Some are more sensitive to falling estrogen levels than others. With a likely diagnosis of menopause-related cognitive impairment, the doctor prescribed hormone-replacement therapy. Within 15 months, the woman’s behavioral symptoms had disappeared and her learning ability and memory were back to normal. She was able to complete a demanding graduate program and assume a new leadership position in education. This woman’s case was admittedly extreme, but Dr. Devi told me that “60 percent of women go through menopause-related cognitive impairment” that, when serious enough to be brought to medical attention, is too often misdiagnosed as “mild cognitive impairment,” a precursor to dementia. © 2018 The New York Times Company

Keyword: Hormones & Behavior; Development of the Brain
Link ID: 25793 - Posted: 12.17.2018