by Laura Dattaro Correcting a mutation in the autism gene SHANK3 in fetal mice lessens some autism-like behaviors after birth, according to a new study1. The work adds to evidence that gene therapy may help some people with SHANK3 mutations. In people, mutations in SHANK3 can lead to Phelan-McDermid syndrome, a condition that causes developmental delays and often autism. Up to 2 percent of people with autism have a mutation in SHANK32. “Our findings imply that early genetic correction of SHANK3 has the potential to provide therapeutic benefit for patients,” lead investigator Craig Powell, professor of neurobiology at the University of Alabama at Birmingham, wrote in an email. A 2016 study showed that correcting mutations in SHANK3 in both young and adult mice can decrease excessive grooming, which is thought to correspond to repetitive behaviors in people with autism. Last year, Powell and his team also showed that correcting SHANK3 mutations in adult mice eliminates some autism-like behaviors3. But the results were difficult to interpret. The team reversed the mutation using an enzyme called Cre-recombinase that could edit SHANK3 if the animals were given a drug called tamoxifen. Control mice in that study that did not receive tamoxifen but had the gene for Cre still showed behavior changes, raising the possibility that the enzyme affected their brains. © 2020 Simons Foundation

Related chapters from BN: Chapter 7: Life-Span Development of the Brain and Behavior
Related chapters from MM:Chapter 4: Development of the Brain
Link ID: 27270 - Posted: 05.29.2020

Peter Hess The relative contributions of genetic and environmental factors to autism and traits of the condition have held steady over multiple decades, according to a large twin study. Among tens of thousands of Swedish twins born over the span of 26 years, genetic factors have consistently had a larger impact on the occurrence of autism and autism traits than environmental factors have. The study suggests that genetics account for about 93 percent of the chance that a person has autism, and 61–73 percent of the odds she shows autism traits. The figures fall in line with previous work that shows genetics exert an outsized influence on autism odds. The findings also indicate that environmental factors are unlikely to explain the rise in autism prevalence. Otherwise, their contribution to autism among the twins would have also risen over time. “I think the relative consistency of the genetic and environmental factors underlying autism and autism traits is the most important aspect of this work,” says Mark Taylor, senior research specialist at the Karolinska Institutet in Stockholm, Sweden, who led the study. “Prior to our study, there had been no twin studies examining whether the genetic and environmental factors underlying autism had changed over time.” Family factors: The researchers analyzed data from two sources: 22,678 pairs of twins in the Swedish Twin Registry, who were born from 1982 to 2008; and 15,280 pairs of twins from the Child and Adolescent Twin Study in Sweden, born from 1992 to 2008. © 1986–2020 The Scientist.

Related chapters from BN: Chapter 7: Life-Span Development of the Brain and Behavior
Related chapters from MM:Chapter 4: Development of the Brain
Link ID: 27262 - Posted: 05.28.2020

by Peter Hess The relative contributions of genetic and environmental factors to autism and traits of the condition have held steady over multiple decades, according to a large twin study 1. Among tens of thousands of Swedish twins born over the span of 26 years, genetic factors have consistently had a larger impact on the occurrence of autism and autism traits than environmental factors have. The study suggests that genetics account for about 93 percent of the chance that a person has autism, and 61 to 73 percent of the odds she shows autism traits. The figures fall in line with previous work that shows genetics exert an outsized influence on autism odds. The findings also indicate that environmental factors are unlikely to explain the rise in autism prevalence. Otherwise, their contribution to autism among the twins would have also risen over time. “I think the relative consistency of the genetic and environmental factors underlying autism and autism traits is the most important aspect of this work,” says Mark Taylor, senior research specialist at the Karolinska Institutet in Stockholm, Sweden, who led the study. “Prior to our study, there had been no twin studies examining whether the genetic and environmental factors underlying autism had changed over time.” The researchers analyzed data from two sources: 22,678 pairs of twins in the Swedish Twin Registry, who were born from 1982 to 2008; and 15,280 pairs of twins from the Child and Adolescent Twin Study in Sweden, born from 1992 to 2008. © 2020 Simons Foundation

Related chapters from BN: Chapter 7: Life-Span Development of the Brain and Behavior
Related chapters from MM:Chapter 4: Development of the Brain
Link ID: 27256 - Posted: 05.20.2020

by Peter Hess Low levels of the hormone vasopressin in early infancy may presage an autism diagnosis in childhood, according to a new study1. Although preliminary, the results suggest that testing vasopressin levels — particularly in infants with high odds of having autism — could flag the condition in the first few months of life. Early identification would allow autistic children to start therapies far sooner than is currently possible, says co-lead investigator Karen Parker, associate professor of psychiatry and behavioral sciences at Stanford University in California. “By the time a child receives an autism diagnosis, they’re pretty far along the path of having these robust social impairments,” Parker says. Previous work has shown that autistic children have, on average, 66 percent less vasopressin in their cerebrospinal fluid than their neurotypical peers, and that low levels of vasopressin track with poor social skills. The new study found a similar trend in infants aged 3 months and younger. “The surprising thing is that this relationship extends to infancy,” before any observable autism traits have emerged, says Larry Young, chief of behavioral neuroscience and psychiatric disorders at Emory University in Atlanta, Georgia, who was not involved with the study. The results, if confirmed, suggest there is a direct biological connection between vasopressin release and autism, Young says. © 2020 Simons Foundation

Related chapters from BN: Chapter 7: Life-Span Development of the Brain and Behavior; Chapter 5: Hormones and the Brain
Related chapters from MM:Chapter 4: Development of the Brain; Chapter 8: Hormones and Sex
Link ID: 27243 - Posted: 05.12.2020

by Giorgia Guglielmi More than half of the genes expressed in the prefrontal cortex, a brain region that is implicated in autism, begin to change their expression patterns in late fetal development, according to a new study1. Previous studies have looked at how DNA variants can influence gene expression at specific developmental periods. This is the first to map their effects in a specific region over the full span of human brain development, says co-senior investigator Stephan Sanders, associate professor of psychiatry at the University of California, San Francisco. “If we ever really want to understand what autism is, understanding human fetal development of the brain is going to be absolutely critical,” Sanders says. Some of the changes in expression patterns vary depending on individual differences in neighboring DNA sequences, the study found. Some of that variation occurs in stretches of the genome linked to neurodevelopmental outcomes, such as how much schooling a person completes (a proxy for intelligence) or whether she develops schizophrenia. “This study creates a resource for trying to understand neurodevelopment and neuropsychiatric disorders,” Sanders says. Fetal expression: The researchers analyzed the prefrontal cortex of 176 postmortem brains from donors ranging in age from 6 weeks post-conception to 20 years. None had any known neuropsychiatric conditions or large-scale genetic anomalies. The team identified 23,782 genes expressed during brain development in the dorsolateral prefrontal cortex, a region implicated in many developmental conditions, including autism. © 2020 Simons Foundation

Related chapters from BN: Chapter 7: Life-Span Development of the Brain and Behavior
Related chapters from MM:Chapter 4: Development of the Brain
Link ID: 27239 - Posted: 05.08.2020

A small study funded by the National Institutes of Health suggests that sleep problems among children who have a sibling with autism spectrum disorder (ASD) may further raise the likelihood of an ASD diagnosis, compared to at-risk children who do not have difficulty sleeping. Previous research has shown that young children who have a sibling with ASD are at a higher risk for also being diagnosed with the condition. The study appears in The American Journal of Psychiatry. If confirmed by other studies, the findings may give clinicians a tool to identify sleep problems early and provide interventions to reduce their effects on the health and development of children with autism. The findings may also provide insights into the potential role of sleep problems in the development of ASD. The study was conducted by Annette M. Estes, Ph.D., of the University of Washington Autism Center in Seattle, and colleagues in the NIH Autism Centers of Excellence Infant Brain Imaging Study Network. NIH funding was provided by the Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD) and the National Institute of Mental Health. “The results are a promising lead,” said Alice Kau, Ph.D., of NICHD’s Intellectual and Developmental Disabilities Branch. “If confirmed by more in-depth studies, patterns of sleep disturbance in early life might be used to pinpoint increased risk for ASD among young children already at risk because they have a sibling with ASD.” The researchers analyzed data from a long-term study of children who do and do not have siblings with ASD. When the children were 6 and 12 months of age, parents were asked to respond to an infant temperament questionnaire that asks how much difficulty their child has falling asleep at bedtime and falling back to sleep after waking up during the night. At these time intervals, the children also received MRI scans to track their brain development. At 24 months, the children were assessed for ASD.

Related chapters from BN: Chapter 7: Life-Span Development of the Brain and Behavior; Chapter 14: Biological Rhythms, Sleep, and Dreaming
Related chapters from MM:Chapter 4: Development of the Brain; Chapter 10: Biological Rhythms and Sleep
Link ID: 27238 - Posted: 05.08.2020

by Laura Dattaro / Autistic people have atypical activity in a part of the brain that regulates attention, according to a new study1. The researchers measured pupil responses as a proxy for brain activity in a brain region known as the locus ceruleus. Located in the brain stem, the region plays a key role in modulating activity throughout the brain, in part by controlling attention. It can broaden and narrow pupils to adjust how much visual information a person receives, for example. Because of this, researchers can use pupil size to infer activity in the region and gauge a person’s focus on a task; a wider pupil indicates increased focus. The locus ceruleus may also be key to regulating the balance between excitatory and inhibitory brain signals. Some research indicates this equilibrium is disrupted in autism, suggesting the region plays a role in the condition’s underlying biology. In the new study, researchers compared autistic and typical people’s pupil responses when performing a task with and without a distracting sound. Typical people’s pupils grew larger when hearing the sound, suggesting a boost in focus directed by the locus ceruleus. By contrast, the pupils of autistic people did not widen, indicating they do not modulate their attention in the same way. This might have profound consequences for autistic people’s sensory experience, the researchers say. © 2020 Simons Foundation

Related chapters from BN: Chapter 7: Life-Span Development of the Brain and Behavior; Chapter 18: Attention and Higher Cognition
Related chapters from MM:Chapter 4: Development of the Brain; Chapter 14: Attention and Higher Cognition
Link ID: 27231 - Posted: 05.05.2020

By Emily Willingham Professional burnout is all too familiar: Go at something too hard for too long, and the motivational tank empties. But burnout for an autistic person isn’t always about overwork, Dora Raymaker, an autistic systems scientist at Portland State University (PSU), found in a study of autistic workers. Instead, the need to mask autistic behaviors through a workday with nonautistic people can cause chronic exhaustion, reduced ability to tolerate stimuli like light or sound, and loss of skills, the study showed through interviews and a survey of social media comments. The work, which Raymaker’s team published last month, highlights a new trend in autism research. Raymaker and colleagues are part of a small but growing number of research teams with autistic members. These groups are shifting the focus in autism research from cause and cure to practical steps, including ones that help autistic people in settings such as the workplace. And they’re publishing some of their findings in a new journal, Autism in Adulthood, which is dedicated to including the perspectives of autistic people in what it publishes. Interest in those perspectives is “skyrocketing,” says Christina Nicolaidis, a co-author on the burnout study. Nicolaidis, a professor in the School of Social Work at PSU, has an adult son who is autistic. Although much research on autism has focused on children, autistic adults who came of age in the 1990s and early 2000s are joining the field and bringing a focus on their own experience. One member of that cohort is TC Waisman, a doctoral candidate at the University of Calgary studying how faculty and staff can improve autistic students’ college experiences. Waisman says she sees researchers increasingly “respecting us as our own self-determined culture and foregrounding our needs in studies.” © 2020 American Association for the Advancement of Science

Related chapters from BN: Chapter 7: Life-Span Development of the Brain and Behavior
Related chapters from MM:Chapter 4: Development of the Brain
Link ID: 27223 - Posted: 04.30.2020

By Neil Genzlinger Mel Baggs, whose forthright writings and films about being a nonverbal person with autism made an impact in the fields of neurodiversity and disability rights, died on April 11 in Burlington, Vt., at age 39. Anna Baggs, Mx. Baggs’s mother, said the cause was believed to be respiratory failure, though numerous health problems may also have played a part. Mx. Baggs, a vigorous blogger, used the term “genderless” as a self-description. “I like that it just means lack of gender, and has no spoken or unspoken secondary meaning,” read a 2018 entry on the blog “Cussin’ and Discussin’: Mel being human in a world that says I’m not.” Many friends and admirers posting about Mx. Baggs’s death on social media used gender-neutral pronouns, while others used the traditional feminine ones. Gender issues, though, were not Mx. Baggs’s major concern. Of more urgency was conveying that people who think and communicate in nontraditional ways are fully human, and that humanness is a spectrum, not something that can be reduced to a normal/abnormal dichotomy. Many people were introduced to these ideas through Mx. Baggs’s short film “In My Language,” posted on the internet in 2007 and given wide exposure through coverage on CNN. For three minutes it shows Mx. Baggs fiddling with the knob on a dresser drawer, rubbing against a book and more. Then it offers “a translation,” as the film puts it. “The previous part of this video was in my native language,” a synthesized voice says. “Many people have assumed that when I talk about this being my language, that means that each part of the video must have a particular symbolic message within it designed for the human mind to interpret. But my language is not about designing words or even visual symbols for people to interpret. It is about being in a constant conversation with every aspect of my environment.” By the time “In My Language” was posted, Mx. Baggs had already drawn considerable attention in the autism world for creating the website “Getting the Truth Out,” a response to an awareness campaign by the Autism Society of America called “Getting the Word Out,” which Mx. Baggs thought made autistic people objects of pity. Part of that attention was skepticism about Mx. Baggs’s claims. Autism online forums can be caustic, with sharp divisions among various factions, and the harshest detractors have accused Mx. Baggs of being a fake. © 2020 The New York Times Company

Related chapters from BN: Chapter 7: Life-Span Development of the Brain and Behavior
Related chapters from MM:Chapter 4: Development of the Brain
Link ID: 27218 - Posted: 04.29.2020

by Peter Hess The mood-stabilizing drug lithium eases repetitive behaviors seen in mice missing SHANK3, an autism gene, according to a new study1. The findings suggest lithium merits further study as a treatment for some people with autism, even though the drug has troublesome side effects, including tremors and impaired memory. “Lithium is, of course, a rather difficult, non-ideal treatment,” says lead investigator Gina Turrigiano, professor of vision science at Brandeis University in Waltham, Massachusetts. “It’s really hard to get people on a lithium regimen that they can tolerate well.” But understanding why lithium works may set the stage for better treatments, she says. About 1 percent of people with autism have mutations in SHANK3. Deletion or mutation of the gene can also lead to Phelan-McDermid syndrome, which is characterized by intellectual disability, delayed speech and, often, autism. Case studies of people with Phelan-McDermid syndrome also suggest that lithium eases behavior problems associated with the condition2. Previous work has shown that SHANK3 helps stabilize neuronal circuits by adjusting excitatory and inhibitory signaling like a thermostat. This process, called homeostatic plasticity, allows neurons to respond to changes in sensory input. © 2020 Simons Foundation

Related chapters from BN: Chapter 7: Life-Span Development of the Brain and Behavior; Chapter 16: Psychopathology: Biological Basis of Behavior Disorders
Related chapters from MM:Chapter 4: Development of the Brain; Chapter 12: Psychopathology: The Biology of Behavioral Disorders
Link ID: 27215 - Posted: 04.27.2020

by Lauren Schenkman Mice with mutations in a gene called DLG2 are anxious and asocial; they also sleep poorly and overgroom themselves, according to a new study1. These characteristics resemble those seen in some people with autism. The results offer the first evidence that mutations in DLG2 may account for some of the condition’s behavioral traits. “This study is a baby step indicating DLG2’s implication in [autism’s] core behavioral symptoms,” says lead investigator Soo Young Kim, assistant professor of pharmacy at Yeungnam University in Gyeongsan, South Korea. A 2013 study reported that mice and people with DLG2 mutations have differences in learning, attention and other cognitive processes2. Last year, a study of nearly 500 families with two or more autistic children identified DLG2 as a candidate gene for autism3. The new work offers “a more full picture” of DLG2’s effect on behavior, says Seth Grant, professor of molecular neuroscience at the University of Edinburgh in Scotland. Grant led the 2013 work but was not involved in the new study. “It’s a useful contribution.” Kim and her colleagues bred male mice that have two mutant copies of DLG2. The animals lack the corresponding protein, which forms part of a neuron’s scaffolding. DLG4, another gene implicated in autism, has a similar role. © 2020 Simons Foundation

Related chapters from BN: Chapter 7: Life-Span Development of the Brain and Behavior; Chapter 16: Psychopathology: Biological Basis of Behavior Disorders
Related chapters from MM:Chapter 4: Development of the Brain; Chapter 12: Psychopathology: The Biology of Behavioral Disorders
Link ID: 27212 - Posted: 04.24.2020

by Peter Hess Early sleep problems predict repetitive behaviors later in childhood1. And toddlers who overreact or underreact to sensory stimuli have more repetitive behaviors and other autism traits later on2. Together, the findings from two independent studies suggest that early behavioral differences may set the stage for restricted and repetitive behaviors, a core characteristic of autism also associated with other conditions of brain development. The studies also highlight areas for early intervention, particularly if further research identifies causal links between these traits. “Addressing sleep problems might be able to improve trajectories,” says Annette Estes, director of the University of Washington Autism Center in Seattle, who led the sleep study. Autistic children are twice as likely to have trouble sleeping as typical children. Their poor sleep has been linked to severe traits including severe repetitive and restricted behaviors. The new study is unusual in that it links sleep problems with a subset of ‘higher-order’ restrictive and repetitive behaviors that include restricted interests, rituals or routines and an insistence on sameness. The study involved 38 autistic children aged 2 to 6 years and 19 children with developmental delay aged 2 to 4. Parents completed a standardized questionnaire about their children’s sleep problems at age 4 — including difficulty falling asleep, short sleep duration and parasomnias such as sleepwalking and night terrors. Clinicians assessed autism traits, including repetitive behaviors, around age 2 and at two or three later points in time. © 2020 Simons Foundation

Related chapters from BN: Chapter 7: Life-Span Development of the Brain and Behavior; Chapter 14: Biological Rhythms, Sleep, and Dreaming
Related chapters from MM:Chapter 4: Development of the Brain; Chapter 10: Biological Rhythms and Sleep
Link ID: 27208 - Posted: 04.22.2020

by Laura Dattaro Children with autistic older siblings have bigger neural responses than controls do in the brain networks that process faces, according to a new study1. The researchers followed these children from infancy to age 7, looking for relationships between neural signals and the children’s face-processing abilities that remained consistent during this period of development. The work is the first to track face processing in so-called ‘baby sibs’ — children who have autistic older siblings. Baby sibs are 20 times as likely to be diagnosed with autism as typical children are, and they often show autism traits early in life. For this reason, researchers frequently study them to get new clues about autism’s underlying biology. The new study shows the importance of monitoring neural activity and behavior over time to better understand autism, says lead investigator Tony Charman, chair of clinical child psychology at King’s College London in the United Kingdom. “If you measure both the neurocognitive abilities and the behaviors at multiple time points, maybe you get a better handle on the causal mechanisms,” Charman says. “If you understand the mechanisms, you’ve got at least a basis for talking about mechanistic-based interventions” — targeted therapies that might help ease autism traits. The team used electroencephalography (EEG) to measure the brain’s responses to faces and objects. One distinctive response, called the P1, occurs about 100 milliseconds after seeing any visual stimulus and is usually larger and faster when looking at a face. The N170 follows about 70 milliseconds later, mostly in the brain’s right hemisphere. This response is thought to mark the moment when the brain distinguishes a face from an object, or one face from another. In autistic children, the N170 is slower than in typical children2. © 2020 Simons Foundation

Related chapters from BN: Chapter 7: Life-Span Development of the Brain and Behavior; Chapter 18: Attention and Higher Cognition
Related chapters from MM:Chapter 4: Development of the Brain; Chapter 14: Attention and Higher Cognition
Link ID: 27204 - Posted: 04.17.2020

by Alla Katsnelson Several regions in the outer layer of the brain are thicker in children and young adults with autism than in their typical peers, a new study finds. The differences are greatest in girls, in children aged 8 to 10 years, and in those with a low intelligence quotient (IQ)1. During typical development, the brain’s outer layer, called the cerebral cortex, thickens until about age 2 and then grows gradually thinner into adolescence as the brain matures. The new study, one of the largest to investigate cortical thickness in autism, aligns with others that indicate this trajectory differs in people with the condition. The findings suggest that brain structure does not change in a uniform way in autism, but instead varies with factors such as age, gender and IQ, says lead researcher Mallar Chakravarty, assistant professor of psychiatry at McGill University in Montreal, Canada. These variations could help explain the inconsistent findings about cortical thickness and autism seen in earlier studies that did not consider such factors, says Christine Wu Nordahl, associate professor of psychiatry and behavioral sciences at the University of California, Davis MIND Institute, who was not involved in the work. “I think this is the type of study we need to be doing as a field, more and more,” she says. The researchers began with unprocessed magnetic resonance imaging (MRI) brain scans of 3,145 participants from previous studies conducted at multiple institutions. © 2020 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 4: Development of the Brain; Chapter 1: Cells and Structures: The Anatomy of the Nervous System
Link ID: 27188 - Posted: 04.14.2020

by Michael Marshall Some people with autism have an unusually large head: This fact has been known since autism was first described in the 1940s. But debate about this finding has raged ever since. How many people with autism have a large head? What causes the enlargement? And does it have any bearing on outcome? Here is what researchers do and do not know about head size in autism. What proportion of people with autism have a large head? When Leo Kanner first described 11 children with autism in a 1943 paper, he noted many unusual features. “Five had relatively large heads,” he reported, and he said no more on the matter. But the sample size was small. Many other scientists noted the same link over the following decades. A 1999 review estimated that 20 percent of people with autism have statistically large head size, or ‘macrocephaly’1. In 2011, the Autism Phenome Project refined this estimate to 15 percent of autistic boys2. The team followed boys with autism from their diagnosis throughout childhood. They focused on whether head size is disproportionate to the rest of the body, rather than simply large. The researchers call this ‘disproportionate megalencephaly’ and say it marks a distinct subgroup of autistic people. “We’ve defined a big-brain form of autism,” says lead investigator David Amaral, distinguished professor of psychiatry and behavioral sciences at the University of California, Davis MIND Institute. No one contests the 15 percent figure, but scientists differ in their interpretation of the finding. “It only applies to a small proportion of children with autism,” says Katarzyna Chawarska, Emily Fraser Beede Professor of Child Psychiatry at Yale University. © 2020 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 4: Development of the Brain; Chapter 1: Cells and Structures: The Anatomy of the Nervous System
Link ID: 27179 - Posted: 04.10.2020

By Lydia Denworth, It is lunchtime on a Sunday in January. At a long table inside a delicatessen in midtown Manhattan, a group of young people sit together over sandwiches and salads. Most of them have their phones out. One boy wears headphones around his neck. But there is less conversation than you might expect from a typical group of friends: One of the boys seems to talk only to himself, and a girl looks anxious and occasionally flaps her hands. The young people in this group are all on the spectrum. They met through a program organized by the nonprofit Actionplay, in which young people with autism or other disabilities work together to write and stage a musical. Each Sunday, the members refine characters and the script, block scenes and compose songs—and then some of them head across the street to have lunch together. “You meet other people just like you,” says Lexi Spindel, 15. The members share a group text in which they call themselves the Wrecking Crew. A few months ago, six of the girls went to see the movie “Frozen II” together. And Lexi and Actionplay veteran Adelaide DeSole, 21, spent a long afternoon at the Spindels’ apartment over the holiday season. The two young women played games and watched “SpongeBob SquarePants” and “Kung Fu Panda” on television. “That was the first time my daughter had a friend over,” says Lexi’s father, Jay Spindel. “That never happened before Actionplay.” © 2020 Simons Foundation

Related chapters from BN: Chapter 7: Life-Span Development of the Brain and Behavior; Chapter 19: Language and Lateralization
Related chapters from MM:Chapter 4: Development of the Brain; Chapter 15: Language and Lateralization
Link ID: 27178 - Posted: 04.10.2020

A new study in Neuron offers clues to why autism spectrum disorder (ASD) is more common in boys than in girls. National Institutes of Health scientists found that a single amino acid change in the NLGN4 gene, which has been linked to autism symptoms, may drive this difference in some cases. The study was conducted at NIH’s National Institute of Neurological Disorders and Stroke (NINDS). Researchers led by Katherine Roche, Ph.D., a neuroscientist at NINDS, compared two NLGN4 genes, (one on the X chromosome and one on the Y chromosome), which are important for establishing and maintaining synapses, the communication points between neurons. Every cell in our body contains two sex chromosomes. Females have two X chromosomes; males have one X and one Y chromosome. Until now, it was assumed that the NLGN4X and NLGN4Y genes, which encode proteins that are 97% identical, functioned equally well in neurons. But using a variety of advanced technology including biochemistry, molecular biology, and imaging tools, Dr. Roche and her colleagues discovered that the proteins encoded by these genes display different functions. The NLGN4Y protein is less able to move to the cell surface in brain cells and is therefore unable to assemble and maintain synapses, making it difficult for neurons to send signals to one another. When the researchers fixed the error in cells in a dish, they restored much of its correct function. “We really need to look at NLGN4X and NLGN4Y more carefully,” said Thien A. Nguyen, Ph.D., first author of the study and former graduate student in Dr. Roche’s lab.

Related chapters from BN: Chapter 7: Life-Span Development of the Brain and Behavior
Related chapters from MM:Chapter 4: Development of the Brain
Link ID: 27165 - Posted: 04.03.2020

by Laura Dattaro / Mice missing an autism gene called SHANK3 respond to much lighter touches than typical mice do, according to a new study1. And this hypersensitivity seems to result from the underactivity of neurons that normally dampen sensory responses. The study is the first to examine sensory sensitivity in mice missing SHANK3. Mice with mutations in other genes tied to autism, including MECP2 and GABRB3, have also been shown to be hypersensitive to puffs of air blown onto their backs. Up to 90 percent of autistic people have sensory problems, including hypersensitivity to sensations such as sound or touch. These disruptions may underlie many of the difficulties autistic people face in navigating the world, says lead investigator Guoping Feng, professor of neuroscience at the Massachusetts Institute of Technology. “Sensory overload is one of the reasons that autistic people cover their ears, [hide] in corners, want to be quiet,” Feng says. “It’s important to understand mechanisms.” Up to 2 percent of people with autism have a mutation in SHANK3, which encodes a protein needed for neurons to communicate with one another2. Autism is also common in people with Phelan-McDermid syndrome, a condition caused by deletions of the chromosomal region in which SHANK3 is located. Other experts also say the study underscores the importance of studying sensory problems in autistic people. “Hyperreactivity to sensory input might be connected with autism in a really deep way,” says Sam Wang, professor of neuroscience at Princeton University, who was not involved in the work. “If sensory experience in the first few years of life is necessary for setting up a model of the world, an understanding of the world, then sensory processing would be a gateway to all kinds of other difficulties.” © 2020 Simons Foundation

Related chapters from BN: Chapter 7: Life-Span Development of the Brain and Behavior; Chapter 8: General Principles of Sensory Processing, Touch, and Pain
Related chapters from MM:Chapter 4: Development of the Brain; Chapter 5: The Sensorimotor System
Link ID: 27151 - Posted: 03.30.2020

Peter Hess The coronavirus pandemic has shuttered universities and institutes, leaving scientists scrambling to continue their research. Hundreds of colleges and universities in the United States have dispatched students home and are aiming to transition to remote learning. Scientific organizations are canceling conferences or moving them online. And scientists have had to put research projects and clinical trials on hold. These decisions—all done with the intention of slowing the pandemic—may stall and stymie research, with long-term consequences for the field. It may also hurt career prospects for graduate students who rely on conference presentations to gain exposure. “From everything that we’re seeing, this isn’t like a two-week hiatus,” says Helen Egger, chair of the child and adolescent psychiatry department at NYU Langone Health in New York City. “We’re in the middle of the hurricane, and there’s no indication how much worse it’s going to get or when it will end.” One long-term benefit is that the crisis may give universities and professional organizations a crash course in embracing technology. “These types of experiences—as long as we are having them, unfortunately—are giving autism [researchers] and other researchers more skills to be able to have online conferences and online teaching as needed,” says Steven Kapp, lecturer in psychology at the University of Portsmouth in the United Kingdom. Backup plans: Some labs were prepared to meet the challenge, and they quickly put their emergency plans into place when news of the pandemic intensified. But, illustrating how rapidly the situation is changing, some of their plans derailed over the weekend. © 1986–2020 The Scientist

Related chapters from BN: Chapter 1: Introduction: Scope and Outlook; Chapter 7: Life-Span Development of the Brain and Behavior
Related chapters from MM:Chapter 20: ; Chapter 4: Development of the Brain
Link ID: 27132 - Posted: 03.21.2020

By Scott Barry Kaufman For many years, researchers have treated the individual traits and characteristics of autistic people as an enduring essence of their autism-- in isolation of the social context and without even asking autistic people what their social life is actually like. However, perspective matters. Who is to say it's autistic people who are the "awkward" ones? A number of myths about autistic people abound. For one, it's a great myth that autistic people lack empathy. This is how they were depicted for so many years in the clinical literature and in the media-- as emotionless, socially clueless robots. However, the more you get to know an autistic person, the more you realize just how caring they can be, even though they may have some difficulties reading social cues. As Steve Silberman points out, empathy is a two-way street. Another common misconception is that autistic people aren't social. I really like some recent approaches that add greater complexity to this issue, showing that when you take a contextual strengths-based approach you can see that people on the autism spectrum are much more social than researchers ever realized. The lens upon which we look at a person matters. As Megan Clark and Dawn Adams put it, "When autism is viewed through a deficit lens the strengths, positive attributes and interests of individuals on the spectrum can be overshadowed." In one recent study, Clark and Adams asked 83 children on the autism spectrum (aged 8 to 15 years) various questions about themselves. When asked "What do you like most about yourself?", the most common themes were "I am a good friend or person to be around" and "I am good at particular things."When asked "What do you enjoy the most?", one of the most endorsed themes was social interaction. © 2020 Scientific American

Related chapters from BN: Chapter 7: Life-Span Development of the Brain and Behavior
Related chapters from MM:Chapter 4: Development of the Brain
Link ID: 27121 - Posted: 03.16.2020