By Jacqueline Howard and Deidre McPhillips, Most families of children with autism may face long wait times to diagnose their child with the disorder, and once a diagnosis is made, it sometimes may not be definitive. But now, two studies released Tuesday suggest that a recently developed eye-tracking tool could help clinicians diagnose children as young as 16 months with autism – and with more certainty. Kids’ developmental disability diagnoses became more common during pandemic, but autism rates held steady, CDC report says “This is not a tool to replace expert clinicians,” said Warren Jones, director of research at the Marcus Autism Center at Children’s Healthcare of Atlanta and Nien Distinguished Chair in Autism at Emory University School of Medicine, who was an author on both studies. Rather, he said, the hope with this eye-tracking technology is that “by providing objective measurements that objectively measure the same thing in each child,” it can help inform the diagnostic process. The tool, called EarliPoint Evaluation, is cleared by the US Food and Drug Administration to help clinicians diagnose and assess autism, according to the researchers. Traditionally, children are diagnosed with autism based on a clinician’s assessment of their developmental history, behaviors and parents’ reports. Evaluations can take hours, and some subtle behaviors associated with autism may be missed, especially among younger children. “Typically, the way we diagnose autism is by rating our impressions,” said Whitney Guthrie, a clinical psychologist and scientist at the Children’s Hospital of Philadelphia’s Center for Autism Research. She was not involved in the new studies, but her research focuses on early diagnosis of autism.

Related chapters from BN: Chapter 7: Life-Span Development of the Brain and Behavior; Chapter 10: Vision: From Eye to Brain
Related chapters from MM:Chapter 13: Memory and Learning; Chapter 7: Vision: From Eye to Brain
Link ID: 28904 - Posted: 09.13.2023

by Calli McMurray One of the co-directors of a now-shuttered Maryland psychology clinic implicated in 18 paper retractions has retired, Spectrum has learned. Prior to her retirement, Clara Hill was professor of psychology at the University of Maryland in College Park. Headshot of Clara Hill. Recent retirement: Clara Hill retired from the University of Maryland in the midst of 18 paper retractions after a 49-year career. Starting on 1 June, the American Psychological Association (APA) retracted 11 papers by Hill and her university colleagues Dennis Kivlighan, Jr. and Charles Gelso over issues with obtaining participant consent. The publisher plans to retract six more papers by the end of the year, according to an APA representative. On 13 August, Taylor & Francis retracted an additional paper led solely by Hill. The research was conducted at the Maryland Psychotherapy Clinic and Research Lab, where Hill, Kivlighan and Gelso were co-directors. The clinic had shut down as of 1 June. When asked about the circumstances surrounding Hill’s retirement, a university spokesperson told Spectrum in an email, “Dr. Clara Hill retired from UMD effective July 1, 2023.” After Spectrum asked again about the circumstances, a spokesperson replied, “This is all we’ll have for you on the faculty member’s retirement — thanks!” Hill worked at the university for 49 years. As of 1 August, Hill’s faculty page did not mention her retirement. By 14 August, her position had been amended to “Professor (Retired),” and a notice of her retirement had been added to the beginning of her biography. Spectrum left two voicemails on Hill’s university office phone and emailed her university address with requests for comment but did not hear back. The 11 papers retracted by the APA appeared in the Journal of Counseling Psychology, Dreaming and Psychotherapy. The additional retractions will come from the same titles, according to an APA representative. Hill conducted all 11 studies, whereas Kivlighan and Gelso conducted 10 and 6, respectively. © 2023 Simons Foundation

Related chapters from BN: Chapter 7: Life-Span Development of the Brain and Behavior
Related chapters from MM:Chapter 13: Memory and Learning
Link ID: 28877 - Posted: 08.24.2023

by Giorgia Guglielmi Mice with a mutation that boosts the activity of the autism-linked protein UBE3A show an array of behaviors reminiscent of the condition, a new study finds. The behaviors differ depending on whether the animals inherit the mutation from their mother or their father, the work also reveals. The results add to mounting evidence that hyperactive UBE3A leads to autism. Duplications of the chromosomal region that includes UBE3A have been associated with autism, whereas deletions and mutations that destroy the gene’s function are known to cause Angelman syndrome, which is characterized by developmental delay, seizures, lack of speech, a cheerful demeanor and, often, autism. “UBE3A is on a lot of clinicians’ radar because it is well known to be causative for Angelman syndrome when mutated or deleted,” says lead investigator Mark Zylka, professor of cell biology and physiology at the University of North Carolina at Chapel Hill. “What our study shows is that just because you have a mutation in UBE3A, it doesn’t mean that it’s going to be Angelman syndrome.” In the cell, UBE3A is involved in the degradation of proteins, and “gain-of-function” mutations — which send the UBE3A protein into overdrive — result in enhanced degradation of its targets, including UBE3A itself. Studying the effects of these mutations could provide insight into how they affect brain development and suggest targets for therapies, says study investigator Jason Yi, assistant professor of neuroscience at Washington University in St. Louis, Missouri. Gain-of-function mutations in UBE3A can disrupt early brain development and may contribute to neurodevelopmental conditions that are distinct from Angelman syndrome, Yi and Zylka have shown in previous studies. One of the mutations they analyzed had been found in an autistic child, so the team used CRISPR to create mice with this mutation. © 2023 Simons Foundation

Related chapters from BN: Chapter 7: Life-Span Development of the Brain and Behavior
Related chapters from MM:Chapter 13: Memory and Learning
Link ID: 28857 - Posted: 07.27.2023

By Harrison Smith As a young boy in small-town Mississippi, Donald Triplett was oddly distant, with no apparent interest in his parents or anyone else who tried to make conversation. He was obsessed with spinning round objects and had an unusual way of speaking, substituting “you” for “I” and repeating words like “business” and “chrysanthemum.” He also showed a savant-like brilliance, naming notes as they were played on the piano and performing mental calculations with ease. When a visitor asked “87 times 23,” he didn’t hesitate before answering — correctly — “2,001.” Mr. Triplett would make medical history as “Case 1,” the first person formally diagnosed with autism. His upbringing and behavior were described at length in a 1943 scientific article by Austrian American psychiatrist Leo Kanner, “Autistic Disturbances of Affective Contact,” which outlined the developmental disability now known as autism spectrum disorder, or ASD. The article went on to describe 10 other autistic children, most of whom were locked away in state schools and hospitals while experiencing communication and behavior challenges. Checking in with his former subjects almost 30 years later, Kanner would write that institutionalization was “tantamount to a life sentence … a total retreat to near-nothingness.” Mr. Triplett, by contrast, gained acceptance and admiration while remaining a part of his community. With support from his family, which could afford to send him to Kanner and which later set up a trust fund to look after him, he graduated from college, got a job as a bank teller and found companionship in a morning coffee club at City Hall. He played golf, sang in a choir and traveled the world, visiting at least three-dozen countries and making it to Hawaii 17 times. By choice, he traveled alone, surprising relatives when he would announce at Sunday dinner that he had recently returned from seeing a golf tournament in California or, in search of an oyster dinner, driven his Cadillac to New Orleans.

Related chapters from BN: Chapter 7: Life-Span Development of the Brain and Behavior
Related chapters from MM:Chapter 13: Memory and Learning
Link ID: 28826 - Posted: 06.21.2023

by Sarah DeWeerdt Many papers about autism-linked genes note that the genes are expressed throughout both the central and the peripheral nervous systems. The proportion of such prolific genes may be as high as two-thirds, according to one 2020 analysis. Yet few studies delve into what those genes are actually doing outside the brain. That’s starting to change. Although autism is typically thought of as a brain condition, a critical mass of researchers has started to investigate how the condition alters neurons elsewhere in the body. Their work — part of a broader trend in neuroscience to look beyond the brain — hints that the role of the peripheral nervous system in autism is, well, anything but peripheral: Neuronal alterations outside the brain may help to explain a host of the condition’s characteristic traits. Much of the research so far focuses on touch and the workings of the gut, but there is increasing interest in other sensory and motor neurons, as well as the autonomic nervous system, which orchestrates basic body functions such as heartbeat, blood pressure, breathing and digestion. It’s difficult to pinpoint whether some autism traits arise in the peripheral nervous system or the central nervous system; in many cases, complex feedback loops link the two. “Your nervous system doesn’t know that we’ve divided it that way,” says Carissa Cascio, associate professor of psychiatry and behavioral sciences at Vanderbilt University in Nashville, Tennessee. But at least some peripheral changes may offer novel treatment targets. And drugs that act in the peripheral nervous system could also prove more effective and have fewer side effects than brain-based therapies, says Julia Dallman, associate professor of biology at the University of Miami in Coral Gables, Florida. © 2023 Simons Foundation

Related chapters from BN: Chapter 7: Life-Span Development of the Brain and Behavior; Chapter 13: Homeostasis: Active Regulation of the Internal Environment
Related chapters from MM:Chapter 13: Memory and Learning; Chapter 9: Homeostasis: Active Regulation of the Internal Environment
Link ID: 28739 - Posted: 04.15.2023

By Azeen Ghorayshi Morénike Giwa Onaiwu was shocked when day care providers flagged some concerning behaviors in her daughter, Legacy. The toddler was not responding to her name. She avoided eye contact, didn’t talk much and liked playing on her own. But none of this seemed unusual to Dr. Onaiwu, a consultant and writer in Houston. “I didn’t recognize anything was amiss,” she said. “My daughter was just like me.” Legacy was diagnosed with autism in 2011, just before she turned 3. Months later, at the age of 31, Dr. Onaiwu was diagnosed as well. Autism, a neurodevelopmental disorder characterized by social and communication difficulties as well as repetitive behaviors, has long been associated with boys. But over the past decade, as more doctors, teachers and parents have been on the lookout for early signs of the condition, the proportion of girls diagnosed with it has grown. In 2012, the Centers for Disease Control and Prevention estimated that boys were 4.7 times as likely as girls to receive an autism diagnosis. By 2018, the ratio had dipped to 4.2 to 1. And in data released by the agency last month, the figure was 3.8 to 1. In that new analysis, based on the health and education records of more than 226,000 8-year-olds across the country, the autism rate in girls surpassed 1 percent, the highest ever recorded. More adult women like Dr. Onaiwu are being diagnosed as well, raising questions about how many young girls continue to be missed or misdiagnosed. “I think we just are getting more aware that autism can occur in girls and more aware of the differences,” said Catherine Lord, a psychologist and autism researcher at the University of California, Los Angeles. © 2023 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: 28737 - Posted: 04.12.2023

By Emily Anthes The prevalence of autism spectrum disorder in American children rose between 2018 and 2020, continuing a long-running trend, according to a study released by the Centers for Disease Control and Prevention on Thursday. In 2020, an estimated one in 36 8-year-olds had autism, up from one in 44 in 2018. The prevalence was roughly 4 percent in boys and 1 percent in girls. The rise does not necessarily mean that autism has become more common among children, and it could stem from other factors, such as increased awareness and screening. “I have a feeling that this is just more discovery,” said Catherine Lord, a professor of psychiatry at the University of California, Los Angeles medical school, who was not involved in the research. “The question is what’s happening next to these kids, and are they getting services?” The rise was especially sharp among Black, Hispanic, and Asian or Pacific Islander children. For the first time, autism was significantly more prevalent among 8-year-olds in these groups than in white children, who have traditionally been more likely to receive autism diagnoses. “These patterns might reflect improved screening, awareness and access to services among historically underserved groups,” the researchers wrote. But why the prevalence in these children has surpassed that in white children is an open question that requires more investigation, Dr. Lord said. An accompanying study, also published on Thursday, suggests that the pandemic may have disrupted or delayed the detection of autism in younger children. © 2023 The New York Times Company

Related chapters from BN: Chapter 7: Life-Span Development of the Brain and Behavior
Related chapters from MM:Chapter 13: Memory and Learning
Link ID: 28717 - Posted: 03.25.2023

ByRachel Zamzow A long-smoldering debate among scientists studying autism has erupted. At issue is language—for example, whether researchers should describe autism as a “disorder,” “disability,” or “difference,” and whether its associated features should be called “symptoms” or simply “traits.” In scientific papers and commentaries published in recent months, some have decried ableist language among their colleagues whereas others have defended traditional terminology—with both sides saying they have the best interests of autistic people in mind. The vitriol is harming the field and silencing researchers, some fear, but others see it as a long-overdue reckoning. Since autism’s earliest descriptions in the academic literature as a condition affecting social interaction and communication, researchers and clinicians have framed it as a medical disorder, with a set of symptoms to be treated. Historically, autistic children have been institutionalized and subjected to treatments involving physical punishment, food restriction, and electric shocks. Even today, the most widely used autism therapy—applied behavior analysis—is seen by some as a harmful tool of normalization. Many autistic people and their families have instead embraced the view that their difficulties lie not with their autism, but with a society that isn’t built to support them. But according to some autism researchers, the field still too often defaults to terms with negative connotations. For example, in addition to “symptom” and “disorder,” many scientists use the term “comorbid” rather than the more neutral “co-occurring” to describe conditions that tend to accompany autism. Similarly, some argue the oft-used phrase “people with autism,” as opposed to “autistic person,” can imply that autism is necessarily an unwanted harmful condition. In a recent survey of 195 autism researchers, 60% of responses included views about autistic people the study authors deemed dehumanizing, objectifying, or stigmatizing. Some responses described autistic people as “shut down from the outside world” or “completely inexpressive and apparently without emotions,” according to the November 2022 Frontiers in Psychology study. “What is worse than I thought was how blatant a lot of the content was, which shows that, for [a] large proportion of participants, they did not consider the things they were saying to be problematic at all,” says lead author Monique Botha, a psychologist at the University of Stirling.

Related chapters from BN: Chapter 7: Life-Span Development of the Brain and Behavior; Chapter 1: Introduction: Scope and Outlook
Related chapters from MM:Chapter 13: Memory and Learning; Chapter 1: Cells and Structures: The Anatomy of the Nervous System
Link ID: 28660 - Posted: 02.08.2023

by Peter Hess An autism-linked mutation in the gene CHD8 yields wildly different physical and behavioral traits in mice depending on their genetic backgrounds, according to a study of 33 mouse strains. The findings were published today in Neuron. The results serve as a stark reminder that traits associated with an autism-linked mutation reflect more than just that mutation, says senior investigator Pat Levitt, chair of developmental neurogenetics at Children’s Hospital Los Angeles in California. Differences in genetic background could also explain why some findings from autism model mice have failed to replicate across labs, he adds. People with CHD8 mutations often have autism, intellectual disability, gastrointestinal issues and macrocephaly — larger-than-average head size — but not all of them have all of these traits. This variability may stem from interactions between the mutations and other variants across the genome, says study investigator Manal Tabbaa, a postdoctoral research fellow in Levitt’s lab. The new work does not reveal how the same CHD8 mutation can affect different mice — or people — differently. But researchers could use the genetically diverse rodents to answer this question, and to better understand and model autism’s heterogeneity, Tabbaa and Levitt say. “This is such a comprehensive approach to understand a really clinically relevant question, and it’s almost unbelievable that just three people could do this amount of work, considering how much it looks like was done,” says Joseph Gleeson, professor of neurosciences at the University of California, San Diego, who was not involved in the study. “They are just scratching the surface of what could be really fantastic future efforts.” © 2023 Simons Foundation

Related chapters from BN: Chapter 7: Life-Span Development of the Brain and Behavior
Related chapters from MM:Chapter 13: Memory and Learning
Link ID: 28657 - Posted: 02.08.2023

by Giorgia Guglielmi About five years ago, Catarina Seabra made a discovery that led her into uncharted scientific territory. Seabra, then a graduate student in Michael Talkowski’s lab at Harvard University, found that disrupting the autism-linked gene MBD5 affects the expression of other genes in the brains of mice and in human neurons. Among those genes, several are involved in the formation and function of primary cilia — hair-like protrusions on the cell’s surface that sense its external environment. “This got me intrigued, because up to that point, I had never heard of primary cilia in neurons,” Seabra says. She wondered if other researchers had linked cilia defects to autism-related conditions, but the scientific literature offered only sparse evidence, mostly in mice. Seabra, now a postdoctoral researcher in the lab of João Peça at the Center for Neuroscience and Cell Biology at the University of Coimbra in Portugal, is spearheading an effort to look for a connection in people: The Peça lab established a biobank of dental stem cells obtained from baby teeth of 50 children with autism or other neurodevelopmental conditions. And the team plans to look at neurons and brain organoids made from those cells to see if their cilia show any defects in structure or function. Other neuroscientists, too, are working to understand the role of cilia during neurodevelopment. Last September, for example, researchers working with tissue samples from mice discovered that cilia on the surface of neurons can form junctions, or synapses, with other neurons — which means cilia defects could, at least in theory, hinder the development of neural circuitry and activity. Other teams have connected several additional autism-related genes, beyond MBD5, to the tiny cell antennae. © 2023 Simons Foundation

Related chapters from BN: Chapter 7: Life-Span Development of the Brain and Behavior; Chapter 2: Functional Neuroanatomy: The Cells and Structure of the Nervous System
Related chapters from MM:Chapter 13: Memory and Learning; Chapter 2: Neurophysiology: The Generation, Transmission, and Integration of Neural Signals
Link ID: 28623 - Posted: 01.07.2023

by David Dobbs For 40 years, Leo Kanner and Hans Asperger have dominated virtually every story about the ‘pioneers of autism research.’ These two men published in 1943 and 1944, respectively, what were long accepted as the first descriptions of, as Kanner’s seminal paper claimed, ”children whose condition differs … markedly and uniquely from anything reported so far.” Both papers are absorbing, touching and authoritative. Both describe young people whose challenges defied the known diagnoses of the time but clearly fall into what we now call autism. And both offered a new diagnostic category for such people. Kanner’s 1943 paper, ”Autistic Disturbances of Affective Contact,” drew almost immediate attention. Within a year, he renamed the condition these children shared, dubbing it ‘early infantile autism,’ which soon became known as ‘autism’ or ‘Kanner’s syndrome.’ His articulation of the condition, based on observations of 11 children he and his associates treated in his Baltimore, Maryland, clinic, remained the standard well into the 1980s and involved three elements: Autism was a condition marked by: (1) emergence early in childhood, (2) deficits in communication and social interaction, and (3) restricted or repetitive behaviors and a desire for sameness. Even today, these three elements anchor the official diagnostic criteria in the American Psychiatric Association’s Diagnostic and Statistical Manual of Mental Disorders, as well as the widely used International Classification of Diseases and Related Health Problems. Asperger’s 1944 paper, which presented case studies on four children he and his colleagues had seen in his clinic in Vienna, Austria, made its impact far more slowly. In fact, because Asperger published in German (and in a German journal in the middle of a war that had essentially halted transatlantic scholarly exchange), the paper went largely unnoticed outside Europe for decades. Asperger’s descriptions resembled Kanner’s in many ways, although he outlined a wider apparent range of intelligence and capabilities than Kanner did, with some of his study participants reaching prominence in their fields. Asperger coined the diagnostic term ‘autistic psychopathy.’ © 2022 Simons Foundation

Related chapters from BN: Chapter 7: Life-Span Development of the Brain and Behavior
Related chapters from MM:Chapter 13: Memory and Learning
Link ID: 28544 - Posted: 11.09.2022

by Angie Voyles Askham / Brain connectivity patterns in people with autism and other neuropsychiatric conditions are more closely related to genetics than to phenotypic traits, according to two new studies. The findings highlight why a single brain biomarker for autism has remained elusive, the researchers say. The condition’s genetic heterogeneity has hampered the search for a shared brain signature: More than 100 genes have been identified as strongly linked to autism, and multiple copy number variations (CNVs) — deleted or duplicated stretches of genetic code — can increase a person’s likelihood of the condition. Autism also often overlaps with other conditions, such as schizophrenia and attention-deficit/hyperactivity disorder (ADHD), making autism-specific markers difficult to disentangle. Common variants tied to autism overlap strongly with those linked to schizophrenia and high IQ, for example, whereas rare autism-linked variants track with low IQ. According to the new papers, however, autism’s genetic heterogeneity corresponds to similarly disparate maps of ‘functional connectivity’ — a measure of which brain areas activate in sync while the brain is at rest. “What we’re seeing is that these groups of variants have specific functional connectivity signatures,” says lead investigator Sébastien Jacquemont, associate professor of pediatrics at the University of Montreal in Canada. The findings need to be replicated, says Aaron Alexander-Bloch, assistant professor of psychiatry at the University of Pennsylvania and the Children’s Hospital of Philadelphia, who was not involved in the work, but they point to the importance of subgrouping study participants based on their underlying genetics. © 2022 Simons Foundation

Related chapters from BN: Chapter 7: Life-Span Development of the Brain and Behavior; Chapter 2: Functional Neuroanatomy: The Cells and Structure of the Nervous System
Related chapters from MM:Chapter 13: Memory and Learning; Chapter 2: Neurophysiology: The Generation, Transmission, and Integration of Neural Signals
Link ID: 28490 - Posted: 09.28.2022

by Charles Q. Choi Infection during pregnancy may be associated with having an autistic child simply because mothers of autistic children are prone to infections, a new study finds. The results suggest that “common infections during pregnancy do not seem increase their children’s risk of autism,” says study investigator Martin Brynge, a psychiatrist and doctoral student of global public health at the Karolinska Institutet in Stockholm, Sweden. “Prevention of maternal infections would likely not affect the prevalence of autism in the population.” A great deal of previous research has linked maternal infection during pregnancy with autism and intellectual disability in children. Whether the former causes the latter, however, has remained uncertain. For instance, both autism and intellectual disability are linked with gene variants that may influence the immune system, so mothers of children with either condition may also just be more vulnerable to serious infections. The new study analyzed data from 549,967 children, including 267,995 girls, living in Stockholm County who were born between 1987 and 2010; about 34,000 of the children had been exposed to a maternal infection requiring specialized health care, according to data from Sweden’s National Patient Register and National Medical Birth Register. Of the exposed children, 3.3 percent have autism, compared with 2.5 percent of unexposed children — a 16 percent increase in the chance of autism. But maternal infection in the year before pregnancy was also linked with a 25 percent greater chance of autism. “Mothers who had an infection during pregnancy may not be comparable to those mothers without infections,” Brynge says. “There may be systematic differences at the group level.” © 2022 Simons Foundation

Related chapters from BN: Chapter 7: Life-Span Development of the Brain and Behavior; Chapter 15: Emotions, Aggression, and Stress
Related chapters from MM:Chapter 13: Memory and Learning; Chapter 11: Emotions, Aggression, and Stress
Link ID: 28488 - Posted: 09.24.2022

by Nora Bradford A well-studied brain response to sound, called the M100, appears earlier in life in autistic children than in their non-autistic peers, according to a new longitudinal study. The finding suggests that the auditory cortex in children with autism matures unusually quickly, a growth pattern seen previously in other brain regions. “It’s a demonstration that when we look for autism markers in the brain, they can be very age-specific,” says lead investigator J. Christopher Edgar, associate professor of radiology at the Children’s Hospital of Philadelphia in Pennsylvania. For that reason, longitudinal studies such as this one — in which Edgar and his colleagues assessed children at up to three different ages — are essential, he adds. “If the two populations being studied have different rates of brain maturation, then the pattern of findings changes across time.” At the time of the first magnetoencephalography (MEG) scan, when the children were 6 to 9 years old, those with autism were more likely to have an M100 response to a barely audible tone in the right hemisphere than non-autistic children were. But this difference disappeared in the next two visits, presumably because the M100 response typically appears during early adolescence. By contrast, the M50 response, which occurs throughout life, beginning in utero, showed no significant difference between the two groups at any visit. The team also evaluated ‘phase locking,’ a measure of how similar a participant’s neural activity is from scan to scan within a certain frequency band. Autistic participants demonstrated more mature phase-locking patterns at the first visit, which then diminished at the later two visits. © 2022 Simons Foundation

Related chapters from BN: Chapter 7: Life-Span Development of the Brain and Behavior; Chapter 9: Hearing, Balance, Taste, and Smell
Related chapters from MM:Chapter 13: Memory and Learning; Chapter 6: Hearing, Balance, Taste, and Smell
Link ID: 28478 - Posted: 09.17.2022

by Charles Q. Choi Children with autism show atypical development of brain regions connected to the amygdala, an almond-size brain structure involved in processing fear and other emotions, a new study finds. The brain regions most affected vary between autistic boys and girls, the study also shows, adding to the growing body of evidence for sex differences in autism, researchers say. “Better understanding of amygdala development and its connectivity can aid in the development of novel biomarkers to study brain and social health,” says Emma Duerden, assistant professor of applied psychology at Western University in London, Canada, who was not involved in the study. The amygdala is a central hub for brain circuits involved in social function. Previous studies have found it to be enlarged in some autistic children compared with non-autistic children, a difference that may be linked with anxiety and depression. In the new study, researchers used structural magnetic resonance imaging to track the growth of 32 brain regions with direct connections to the amygdala. The study participants included 282 autistic children, 93 of whom are female, and 128 non-autistic children, 61 of whom are female. The researchers scanned each child up to four times — when the children were 39, 52, 64 and 137 months old, on average. They also measured the children’s autism traits and social difficulties using a questionnaire filled out by parents, called the Social Responsiveness Scale-2. Autistic children had larger amygdala-connected brain regions than non-autistic children at all ages. The differences grew over time and were most apparent among the autistic children with prominent social difficulties. The researchers found no differences in the size of brain areas not directly connected to the amygdala between children with and without autism. © 2022 Simons Foundation

Related chapters from BN: Chapter 7: Life-Span Development of the Brain and Behavior; Chapter 15: Emotions, Aggression, and Stress
Related chapters from MM:Chapter 13: Memory and Learning; Chapter 11: Emotions, Aggression, and Stress
Link ID: 28398 - Posted: 07.14.2022

by Charles Q. Choi The primordial cells that give rise to most other brain cells do not proliferate in a typical way in autistic people — and that could explain how common traits emerge from a range of genetic origins, according to a new study. The idea that autism disrupts the proliferation of neural precursor cells isn’t new, but until now, few studies had investigated how that difference arises. In the new study, scientists fashioned neural precursor cells out of cord blood cells from five autistic boys ages 4 to 14 and, to serve as controls, either their non-autistic brothers or unrelated non-autistic people. Three of the autistic children have idiopathic cases, in which there is no known genetic cause for their autism; the other two have deletions in 16p11.2, a chromosomal region linked to autism and other neuropsychiatric conditions. Three of the autistic children have macrocephaly, or a large head. Neural precursors from the autistic boys all proliferated in atypical ways, the scientists found. Among children with macrocephaly, this growth was accelerated, leading to 28 to 55 percent more cells than in the non-autistic controls after six days. In contrast, cells from the other two boys, both with idiopathic autism, grew more slowly and more of those cells died, yielding 40 to 65 percent fewer cells than in controls after six days. “Despite the fact that these individuals are genetically distinct, especially the idiopathic individuals, it is amazing they have a common developmental process dysfunction — control of proliferation,” says study co-lead investigator Emanuel DiCicco-Bloom, professor of neuroscience, cell biology and pediatrics at Rutgers University in Piscataway, New Jersey. © 2022 Simons Foundation

Related chapters from BN: Chapter 7: Life-Span Development of the Brain and Behavior
Related chapters from MM:Chapter 13: Memory and Learning
Link ID: 28363 - Posted: 06.11.2022

by Laura Dattaro Two new studies untangle how various classes of genetic variants underpin the vast differences in traits seen among people diagnosed with autism. The studies were published yesterday in Nature Genetics. “The fundamental question behind this is heterogeneity in autism,” says Varun Warrier, a postdoctoral researcher in Simon Baron-Cohen’s lab at the University of Cambridge in the United Kingdom and an investigator on one of the studies. The presence and intensity of core autism traits and co-occurring conditions vary widely among autistic people. The new studies, from largely independent teams, sought to unravel how different categories of genetic variants — rare, common, inherited and spontaneous — contribute to this heterogeneity. Though the two sets of findings conflict in some ways — potentially because of methodological differences — the papers add to the evidence that common and rare variants contribute to autism’s genetic architecture differently, says Yufeng Shen, associate professor of systems biology at Columbia University, who was not involved in either study. “When we say different, it’s not black and white,” Shen says. “They overlap, but it seems like, qualitatively, they have different contributions.” Warrier and his colleagues analyzed genetic and behavioral data from 12,893 autistic people. The data came from the Autism Genetic Resource Exchange, the Longitudinal European Autism Project, the Simons Simplex Collection and SPARK. (The Simons Simplex Collection and SPARK are funded by the Simons Foundation, Spectrum’s parent organization.) © 2022 Simons Foundation

Related chapters from BN: Chapter 7: Life-Span Development of the Brain and Behavior
Related chapters from MM:Chapter 13: Memory and Learning
Link ID: 28356 - Posted: 06.07.2022

by Rachel Zamzow Inflammation may inflate or thin out brain regions tied to autism and schizophrenia, researchers report in a new study. The findings add nuance to the long-held hypothesis that immune activation elevates the risk for neurodevelopmental conditions. Autism, for example, is associated with prenatal exposure to infection, previous studies show. Taking a different approach, the new work focuses on how a genetic predisposition to inflammation affects brain development in the general population, says John Williams, research fellow at the University of Birmingham in the United Kingdom, who conducted the work with lead researcher Rachel Upthegrove, professor of psychiatry and youth mental health at the university. By pinpointing where inflammation leaves its mark in the brain, the findings serve as a guidepost for future studies of people with neuropsychiatric conditions, he says. “We think that it points to something that’s fairly transdiagnostic.” For their analyses, the team drew on brain imaging and genetic data from 10,828 women and 9,860 men in the general population who participated in the UK Biobank. They explored how 1,436 possible structural changes in the brain track with having single-nucleotide variants previously shown to increase circulating levels of five inflammatory molecules — interleukin 1 (IL-1), IL-2, IL-6, C-reactive protein and brain-derived neurotrophic factor. Three variants thought to boost IL-6 were associated with 33 structural changes, most notably increased volume in the middle temporal gyrus and fusiform gyrus, and decreased cortical thickness in the superior frontal gyrus — all brain areas implicated in autism. Variants associated with other inflammatory molecules did not track with brain changes, the researchers found. © 2022 Simons Foundation

Related chapters from BN: Chapter 7: Life-Span Development of the Brain and Behavior; Chapter 2: Functional Neuroanatomy: The Cells and Structure of the Nervous System
Related chapters from MM:Chapter 13: Memory and Learning; Chapter 2: Neurophysiology: The Generation, Transmission, and Integration of Neural Signals
Link ID: 28317 - Posted: 05.07.2022

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

Related chapters from BN: Chapter 7: Life-Span Development of the Brain and Behavior
Related chapters from MM:Chapter 13: Memory and Learning
Link ID: 28291 - Posted: 04.20.2022

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

Related chapters from BN: Chapter 7: Life-Span Development of the Brain and Behavior
Related chapters from MM:Chapter 13: Memory and Learning
Link ID: 28284 - Posted: 04.16.2022