The Autism studies/research thread

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Researchers at Rambam Medical Center in Haifa have identified a genetic mutation linked to a certain type of autism, developmental delays and movement disorders.

The mutation in the TBCB gene (Tubulin Folding Cofactor B), discovered by Dr. Sharon Bratman-Morag and Dr. Karin Weiss, is carried by one in 80 Ashkenazi Jews.

If both parents carry the gene, there is a 25 precent chance that their child could inherit the condition and show related symptoms.

The Health Ministry incorporated a screening test for the TBCB gene mutation as part of the national healthcare basket in November, making it accessible to all couples planning for pregnancy.

“The discovery can help families understand the risks to their pregnancies,” Bratman-Morg told The Times of Israel. “It also shows the increasing capabilities of genetic screening.”

What is autism spectrum disorder?
The causes of autism can be genetic. Israeli researchers, for example, have found gene mutations that might cause SHANK3 autism, a type of genetic autism that affects one million people worldwide. People with this autism may have delayed or absent speech, difficulties with social interaction, motor impairment and repetitive behaviors.

Environmental factors can also cause ASD. A study by Dr. Haitham Amal of the Hebrew University of Jerusalem found a link between nitric oxide, a compound in air pollution, and autism.

A recent study by Ben-Gurion University in the Negev, Clalit Healthcare and the Health Ministry found a significant increase in ASD in Israel, rising from 14,914 in 2017 to 32,222 in 2021.

This figure corresponds to significant increases in ASD around the world.

The Ashkenazi gene connection
Bratman-Morag, who is currently doing an internship in clinical genetics at Rambam, said that during her rotation at the Rambam Genetic Institute under Dr. Karin Weiss’s supervision six years ago, she and Weiss met a family of Ashkenazi Jewish origin.

Both of their children had mild cognitive impairment and ASD. They also had a movement disorder known medically as hereditary spastic paraparesis. This disorder affects the spinal cord and nerves, causing stiffness in the leg muscles and making walking and balancing difficult.

“We couldn’t find an explanation for their symptoms using regular genetic tests,” Bratman-Morag said.

The researchers used a special test that looks at the exome, a part of the DNA used for making proteins and where many genetic diseases originate.

“We found that both children had two copies of a faulty version of the TBCB gene,” she said. “We saw that both parents were carriers with one normal copy of the gene and one faulty copy.”

In a healthy body, the TBCB gene helps maintain a cell’s shape and supports its structure. However, mutations in the TBCB gene can disrupt how cells work in the brain, causing developmental and movement disorders.

“The TBCB gene had never been connected to any disease before,” Bratman-Morag said.

To understand further, the researchers teamed up with scientists at the Technion Faculty of Medicine.

At Prof. Daniel Kornitzer’s lab, the researchers used a yeast model. At Prof. Adi Salzberg’s lab, they used a fly model, in which they did gene editing using CRISPR, a tool that allows scientists to make precise changes in the structure of DNA.

Yeast and flies are often used in scientific experiments because they share some genetic similarities with humans.

“We also tested the two patients’ cells at Dr. Weiss’s lab,” Bratman-Morag said.

The experiments confirmed that the TBCB genetic mutation could lead to ASD and related disorders.

In non-Jewish populations, Bratman-Morag said, the occurrence of TBCB is 5:100,000.

In Ashkenazi Jews, the rate is 1:80. During their years of research, the researchers found eight more patients around the world with the same mutation.

“All of them are Ashkenazi Jews,” she said.

TBCB genetic testing in the national healthcare basket
In November, the Health Ministry began to include the TBCB gene testing in the national healthcare basket. It is accessible to all Israelis and not only Ashkenazi Jews.

“Nowadays in Israel, many people can’t really tell their exact origin,” she said. “This fact, and the fact that the cost of genetic tests is lower than previously, helped the ministry’s decision of one screening test for all.”

When two parents are carriers of the gene, Bratman-Morag said, “they have a one in four possibility of having a child with this syndrome.

Then, parents have options.

They can choose to have an abortion, she said, or to have in-vitro fertilization with genetic screening, in which only embryos without two abnormal copies of the TBCB gene are put into the uterus.

The third option is to keep the pregnancy, she said.

A year after the child is born, she said, parents will be able to see if their child has difficulty with motor development.

In that case, “they can give the child physiotherapy at an early age and help them develop,” Bratman-Morag said.

The illness “causes them difficulties with walking, but they can learn to live with that,” she said.

To this end, a team of researchers from the United States of America has developed an advanced screening model to identify toddlers with autism from underserved areas. Their model holds the potential for accessible diagnosis for toddlers from culturally and linguistically diverse backgrounds.

However, there is a lack of valid ASD screening measures, particularly among the under-resourced and culturally and linguistically diverse (CLD) communities. Physical barriers like distance, combined with social and cultural barrier, often delay in screening, negatively impacting the neurodevelopment of toddlers. Researchers are now focusing on the development of tools that can help in early diagnosis, along with training the primary care (PC) and early intervention (EI) providers.

Advancing research, a team of researchers led by Dr. Roula Choueiri from the Kennedy Krieger Institute, USA, developed a new, interactive screening model called the Rapid Interactive Screening Test for Autism in Toddlers (RITA-T). The developed model offers precise and quick diagnosis for kids between the age of 18 to 36 months. It can help PC and EI providers in the diagnosis of high-risk toddlers and help family members with important information and referrals. This study, published in Pediatric Investigation on September 27, 2024, explores the potential of RITA-T to improve early identification of high-risk toddlers from underserved areas. Explaining more about the study, Dr. Choueiri says, “For our study, we compared the demographic and socioeconomic traits of two groups of toddlers diagnosed with ASD. One group underwent the RITA-T screening and the other did not.”

Over the course of a 14-month long study, the team trained EI providers and assisted PC providers in implementing the RITA-T model in their practice. PC providers used the RITA-T alongside the standard Modified Checklist for Autism in Toddlers, revised with follow-up (MCHAT-R/F). These cases were then recommended to specific urban tertiary care centers called the Autism-R diagnosis clinic. For the group that did not perform RITA-T screening, the MCHAT-R score and a parent-completed questionnaire were necessary and these patients were recommended to standard Autism-S clinic.

In both the groups, toddlers underwent 90-minute diagnostic evaluations conducted at these centers by neurodevelopmental pediatricians or neurology nurse practitioners. The team of researchers then assessed demographic and socioeconomic factors, including gender, race, ethnicity, travel time, and wait times for diagnosis. Some statistical tests were performed to compare the data collected from the two groups.

The findings revealed interesting insights into the demographic and socioeconomic characteristics. While the gender and age of the toddlers belonging to both the groups were similar, there was a significant difference in travel time and wait time. Toddlers in the RITA-T group traveled longer distances for their evaluations but shorter wait times from referral to appointment.

The study also considered the Area of Deprivation Index (ADI), which combines socioeconomic indicators like income, education, employment, housing, and transportation, to identify areas with high levels of deprivation. The ADI score for toddlers referred to through the RITA-T system was high, indicating that they come from neighborhoods with deprived socioeconomic conditions. Additionally, households in the RITA-T group had lower incomes compared to the non-RITA-T group.

These findings support the success of the RITA-T screening approach. Since the PC questionnaire was not mandatory for RITA-T-based screening, the diagnosis became easily-accessible for families, who are not conversant with English as a language. It also allowed screening of patients staying further away from urban centers. Maria DeMeo, a pediatric nurse practitioner at Boston Children’s Hospital and a member of the research team, mentions, “More patient referrals during the study period may have resulted from the RITA-T method’s ability to streamline and expedite the entire screening process.”

While these findings are significant, this observational study included more patients screened via RITA-T model, which led to comparison between two unbalanced group sizes. Also, the data regarding the race and ethnicity of the patients was not very clear. However, the participating EI and PC practitioners agreed that using the RITA-T model and integrating it into their programs was easy. Sharing his concluding thoughts with us, Dr. Choueiri says, “The model definitely improves wait time and access to diagnostic services. It also reduces the burden of excessive paperwork, making it easier for family members.”

A new study published in the Journal of Attention Disorders has revealed key factors linked to maladaptive daydreaming in neurodivergent adults. Emotional dysregulation, internalized stigma, escapism, and self-esteem emerged as significant predictors, varying across individuals with autism spectrum disorder, ADHD, and both diagnoses. These findings offer insights into how neurodivergent individuals use vivid daydreaming as a coping mechanism for emotional and social challenges.

Maladaptive daydreaming is a condition in which individuals engage in excessive, vivid, and immersive fantasies that interfere with their ability to function in daily life. Unlike ordinary daydreaming, which is often brief and inconsequential, maladaptive daydreaming is characterized by a loss of control, where individuals feel compelled to spend hours absorbed in their imagined worlds. This behavior frequently disrupts important activities, such as work or relationships, and can cause significant distress.

Maladaptive daydreaming is a relatively new and understudied area of research, although it is gaining more recognition among researchers and the general population, especially online,” said study author Anna Pyszkowska of the University of Silesia in Katowice.

“There is some research about maladaptive daydreaming and its correlations with autistic or ADHD traits, but no study has investigated these aspects simultaneously. We wanted to see if there are significant differences in maladaptive daydreaming rates in these populations. Additionally, we wanted to examine whether individuals on the autism spectrum, with ADHD, or with AuDHD vary in how they experience maladaptive daydreaming, including whether there are different predictors.”

The researchers conducted their study by recruiting participants who had been formally diagnosed with autism spectrum disorder, ADHD, or both conditions. Participants were primarily recruited online through neurodivergent advocacy groups and mental health clinics in Poland. The sample included 139 individuals with ADHD, 74 with autism, and 80 with both diagnoses.

The study found that maladaptive daydreaming was similarly prevalent across all three groups, with 37% to 46% of participants meeting the criteria. However, the key factors contributing to the condition varied among the groups.

Emotional dysregulation emerged as a significant predictor of maladaptive daydreaming, particularly for individuals with autism. Difficulties in identifying and managing emotions were strongly linked to excessive daydreaming in this group, suggesting that daydreaming may serve as a coping mechanism for emotional challenges.

contrast, among participants with ADHD, only certain aspects of emotional dysregulation, such as difficulty accepting emotional responses, predicted maladaptive daydreaming. This finding indicates that the role of emotional dysregulation differs based on the neurodevelopmental condition.

Escapism, particularly self-suppression escapism, was another consistent predictor of maladaptive daydreaming across all groups. This supports the idea that maladaptive daydreaming functions as a way to avoid negative emotions or difficult realities.

Internalized stigma, including feelings of alienation and social withdrawal due to societal judgment, was strongly associated with maladaptive daydreaming, especially among individuals with autism. These findings highlight the social and emotional burdens faced by neurodivergent individuals, which may drive them to retreat into fantasy worlds.

In terms of self-esteem, low self-competence was linked to maladaptive daydreaming in individuals with autism, while higher self-liking predicted lower levels of daydreaming in participants with ADHD.

Interestingly, while ADHD symptoms were more strongly associated with maladaptive daydreaming than autistic traits, individuals with both diagnoses displayed unique patterns. These participants exhibited higher levels of emotional dysregulation, internalized stigma, and self-suppression escapism compared to those with only ADHD or autism. This suggests that the interplay of symptoms from both conditions exacerbates the factors contributing to maladaptive daydreaming.

“The key takeaway is that maladaptive daydreaming is, in fact, associated with attention and emotion dysregulations, and can also be considered as one’s way of escaping from an unpleasant reality,” Pyszkowska told PsyPost. “The latter is additionally important in the neuroatypical population as they often experience stigma and discrimination that may lead to internalized stigma: a situation when you accept and internalize negative stereotypes about yourself and apply them to your own self-perception.”


“Our research showed that the more internalized stigma and dysregulation you experience, the more you want to escape from this reality into your daydreams. Interestingly, there were differences in predictions of maladaptive daydreaming in our three populations studied which showed that it is important to investigate these topics in complex ways.”

However, as with all research, there are some limitations. The sample size was relatively small, especially for the autism-only group, and participants were recruited online, which may have introduced bias. “The sample in this study may be biased as the invitation informed participants that the study was investigating daydreaming in the neurodivergent population,” Pyszkowska noted. “This may have led to the overrepresentation of maladaptive daydreamers, as the topic attracted their attention.”

Future research could address these limitations by including larger and more diverse samples. Further investigation into the content and functions of daydreaming, particularly how it varies across neurodivergent populations, would also provide deeper insights. Exploring potential interventions, such as emotion regulation training or stigma reduction programs, could help individuals manage maladaptive daydreaming more effectively.

A new study from UCLA Health adds to the growing body of evidence on the cognitive benefits of speaking multiple languages, finding that multilingualism not only enhances general cognitive abilities but also may help reduce certain symptoms and bolster control of daily thoughts and actions in children with and without autism.

The study, published in the journal Autism Research, found parents of autistic and non-autistic children in multilingual households reported their children had stronger overall executive function, including the ability to focus, understand other people’s perspectives, communication and reduced levels of repetitive behaviors, compared to children in mono-lingual households.

“It turns out that speaking multiple languages, whether or not you have a diagnosis of autism, is associated with better inhibition, better shifting or flexibility, and also better perspective taking ability,” said study lead author Dr. Lucina Uddin, a UCLA Health Psychiatry and Biobehavioral Sciences Professor and Director of the UCLA Brain Connectivity and Cognition Laboratory.

Conducted initially at the University of Miami, the study recruited more than 100 autistic and non-autistic children ages 7 to 12 from both monolingual and multilingual households. Most of the multilingual households spoke Spanish and English at home.

Parents were asked to score their child’s executive function skills, which are often affected by autism spectrum disorder. Skills assessed included:

Inhibition: the ability to suppress doing something irrelevant or get distracted.
Working memory: the ability to keep something in mind, such as remembering a phone number.
Shifting: the ability to switch between two or more different tasks, such as playing with toys and cleaning up after.
Parents were also asked to score some of the core abilities affected by autism such as the ability to understand different perspectives, social communication and repetitive behaviors.

Results from the survey found multilingualism is associated with better inhibition, shifting and perspective taking skills in children both with and without autism.

“If you have to juggle two languages, you have to suppress one in order to use the other. That’s the idea, that inhibition might be bolstered by knowing two languages,” Uddin said.

Speaking multiple languages also positively affected some of the core symptoms of autism, resulting in improved communication, reduced repetitive behaviors and improved perspective taking skills, Uddin said.

Uddin said there can be a concern among parents of autistic children that speaking multiple languages could contribute to delays in their child’s development relating to language learning. However, she said the evidence so far has suggested no negative impacts and possible long-term benefits.

From these findings, Uddin is expanding the study and addressing limitations. The new study will recruit about 150 children with autism and will include more executive function and language tests as well as brain imaging.

Layer 5 pyramidal neurons play a critical role in integrating and distributing information across neural circuits in the brain. These neurons are found in the outer layers of the brain and are particularly important in processing and relaying information. A recent study conducted by researchers from VIB-KU Leuven and the University of Dundee focused on two specific types of these neurons: intratelencephalic (IT) neurons and pyramidal tract (PT) neurons. Each type has distinct functions and synaptic properties that influence how they communicate within neural networks.

Intratelencephalic (IT) neurons
A type of pyramidal neuron that connects different regions within the cerebral cortex. IT neurons play a role in higher-order cognitive functions.

Pyramidal tract (PT) neurons
Neurons that project information from the cerebral cortex to the brainstem and spinal cord. PT neurons are involved in motor control and other functions.

Using proteomics to study mouse neurons
The research team utilized proteomics, a technique for analyzing the protein composition of cells, to map the synaptic proteins of IT and PT neurons in mice. Synapses, the points of communication between neurons, contain a variety of proteins that determine how signals are transmitted. By comparing the synaptic proteins of these two neuron types, the team identified both shared and unique features.

Synapse
A structure that allows neurons to communicate with each other. It consists of a presynaptic terminal, synaptic cleft and postsynaptic membrane, where chemical signals are exchanged.

These differences are not merely structural but are also functional. Variations in protein composition between IT and PT neurons could impact how they contribute to brain function and may explain their differential vulnerabilities to neurodevelopmental and psychiatric conditions.

Implications for autism and schizophrenia
The study highlights that IT neurons might be more susceptible to disruptions linked to autism spectrum disorders. Further research supported by the Simons Foundation will explore how genes associated with autism might alter the synaptic composition and connectivity of IT neurons. Understanding these differences could provide insights into why certain neurons are more prone to being affected by these conditions, although the findings are still limited to preclinical models.

PT neurons, on the other hand, may have vulnerabilities tied to other neurological or psychiatric disorders. The research underscores the need to profile additional neuron types to develop a more comprehensive understanding of their roles in both health and disease.

Future research directions
The team aims to expand this synaptic profiling approach to include other neuron types across the brain. Such work could pave the way for identifying new targets for therapeutic interventions. However, the current study does not directly translate to human health as it was conducted on mouse neurons. Further studies are required to confirm whether these findings are applicable to humans.

How Neandertal DNA May Affect the Way We Think).

Neandertal DNA has also been associated with substance use such as drinking and smoking. Other genetic variants seem to increase pain sensitivity and prompt people to consume more pain medications. And a subset of Neandertal DNA variants may increase some people’s likelihood of developing attention deficit hyperactivity disorder (ADHD), although these variants are slowly disappearing from the modern human genome.
One particularly intriguing connection that the two of us have been investigating is the possible link between Neandertal ancestry and autism. We first became interested in this link when we learned of the parallels between some of the brain connectivity patterns in visual- and social-process­ing pathways in nonautistic people who have more Neandertal DNA and people on the autism spectrum. People with autism often have enhanced visuospatial abilities—for instance, they tend to excel at picking out a target shape from a sea of distracting shapes in cognitive tests. At the same time, challenges with social cognition are typically central to the autistic experience and call to mind the reduced connectivity in those same neural pathways in nonautistic people with more Neandertal DNA. We also knew that just as Neandertals had smaller cerebellums than early modern humans did, which may have influenced their social cognitive abilities, people with autism consistently exhibit reduced volume in subregions of the cerebellum.

This wealth of data from genetics, neuro­imaging and brain reconstruction prompted the two of us to question whether Neandertal DNA could be influencing autism susceptibility in modern human populations. Our laboratories set out to address this important question together, accessing genetic data on both autistic and nonautistic people from several large, well-established databases. We were also interested in looking at Neandertal DNA according to ethnic background because there is a lot of variability across modern populations. For instance, people of African ancestry tend to have less Neandertal DNA than Asian and European people. Thus, it was important to match our groups of autistic and nonautistic people according to ethnicity.

When studying Neandertal DNA in the modern human genome, scientists typically investigate single points in the DNA that vary across populations. These points of variation are known as single nucleotide polymorphisms (SNPs, pronounced “snips”). We were very interested in studying common and rare Neandertal SNPs separately because the rarer a DNA variant is, the more likely it is to be harmful and the less likely it is to be passed down to offspring. What we found was that autistic people tend to have more rare Neandertal SNPs than ethnically matched nonautistic people have. It’s important to note that autistic people don’t necessarily have more Neandertal DNA in general—they’re not more “Neandertal” than the next person. It’s just that the Neandertal DNA they carry includes more of the rare variants than nonautistic people tend to have.

Neandertal DNA variants appear to be influencing development of autism in measurable ways across ethnicities.

We also investigated SNPs that specifically influence gene activity in the brain. We were able to identify 25 of these Neandertal-derived expression quantitative trait loci (eQTLs), as they are known, that were overrepresented in our autism groups. For example, about 80 percent of white Hispanic autistic males with epilepsy carried a particular Neandertal SNP in the USP47 gene, compared with 15 percent of those in the nonautistic control group. Although the function of USP47 is poorly understood, this gene has tentative links with epilepsy, which often co-occurs with autism.

In addition, we found a mutation in the COX10 gene that occurred more frequently in Black people with autism than in Black people without autism. Animals genetically engineered so that their COX10 is inactive tend to have a functional imbalance between the activity of excitatory neurons and inhibitory ones in the brain that is very characteristic of conditions like autism.

We don’t yet have a clear idea of what all these Neandertal SNPs are doing in people with autism. They appear to be influencing development of the condition in measurable ways across all ethnicities studied. And our research suggests that many of the rare Neandertal-derived SNPs, which are associated with autism, help to orchestrate neural connectivity, which in turn may affect how neurons communicate with one another. But precisely how these variants are affecting brain development remains to be determined. In all likelihood, there is no single answer.

Genetics is an extremely complicated field of study. Although the human genome was sequenced more than 20 years ago, our understanding of molecular networks and how they influence organ development and function is still relatively rudimentary. As we dig deeper into how Neandertal DNA is influencing our genes, it is important to accept the complexity of the problem. There are more than 78,000 modern human genes that have mixed with nearly the same number of Neandertal genes. Humans can wrap their minds around a three-dimensional problem, but a 78,000D problem is rather more difficult! Fortunately, modern computers executing art­i­fic­ial-­intel­li­gence code can handle the analytical burden that our brains cannot.

Our initial study tagged Neandertal DNA in partial genome sequences that constitute just 1 percent or so of the entire human genome. In the next phase of our research we will scan recently available complete genome sequences from modern human families with a propensity for autism. By expanding our search area for ancient DNA from genes to regions between genes, we will be able to investigate millions of additional eQTLs, which regulate the intensity of gene expression much as a dimmer switch controls the amount of light coming from a bulb. Once we map these eQTLs to Neandertal-derived DNA variations in a modern human genome, we will be able to infer whether some Neandertal DNA is measurably altering gene expression.

A complete genome search will allow us to identify eQTLs from the Neandertal lineage that are involved in the function and development of not only the brain as a whole but also specific brain tissues and regions, such as the cerebellum. We may find that H. sapiens inherited entirely new neurodevelopmental traits from Neandertals that did not exist in our lineage until the two groups interbred. A more likely scenario, however, is that the introduction of Neandertal DNA into H. sapiens modified, but did not override or replace, genetic control mechanisms for extraordinarily complex brain conditions such as autism, ADHD and depression.

If we can identify the exact neurodevelopmental pathways controlled by mixed Neandertal/H. sapiens gene regulatory networks, we may be able to figure out how ancient DNA reconfigured gene expression in the brain at the point of hybridization. This type of knowledge would have a variety of potential therapeutic applications within the burgeoning field of personalized medicine.

We aren’t interested only in Neandertal DNA. It may be that hybridization in general, not just DNA inherited from Neandertals specifically, contributes to autism susceptibility—the result of a type of genetic mismatch, if you will. If that’s the case, we might also expect to see DNA from other cousins, the Denisovans, who also interbred with early H. sapiens, playing roles in autism and other neurological conditions in ethnic groups of people today who carry Denisovan DNA (primarily people of Asian and Native American ancestry). We will be looking for signs of Denisovan influence in the next phase of our research.

Like the ADHD-related Neandertal variants that are gradually getting winnowed out of the modern human genome, the rare Neandertal variants that autistic people have may be getting weeded out of the gene pool, too. Some rare Neandertal DNA is probably fading away simply as a result of what population geneticists call the law of large numbers, which predicts that uncommon and rare DNA, regardless of its effects on the organism, will tend to slowly disappear from a large breeding population over time. But other Neandertal DNA may be rare because it is modestly harmful, affecting an individual’s ability to have children and pass down their DNA.

We know from research that, on average, people with autism are significantly less likely than the general population to have children, although there are certainly some who do have kids. But we don’t know whether their reproductive rates are lower because people on the autism spectrum face challenges with romantic relationships or because they are more likely to have certain health-related disorders such as polycystic ovary syndrome that affect fertility. The answer is probably multifactorial. But regardless of the reasons, fewer offspring means fewer genetic variants associated with autism get passed down over time. So, if these variants aren’t getting passed down as often, why are they still sticking around in the human genome, albeit in low numbers?

When it comes to autism, the medical community has traditionally focused on the deficits and challenges that people with the condition may experience. This approach is rooted in the medical model of disability, which in the case of neurodevelopmental differences holds that they should be treated medically with a focus on “fixing” or managing the condition and a goal of normalizing the person’s behavior. But the autism spectrum is also associated with traits that may have been adaptive during more recent human brain evolution—enhanced visuospatial processing, high intelligence, exceptional memory and creativity, among others. Multiple genetics studies have found that many of the common genetic variants associated with autism are also associated with high intelligence, enhanced cognitive ability and educational attainment.

In addition, family members of people on the spectrum are more likely to have careers in fields related to science and technology and, according to our recent study, are also likely to carry some of these same rare Neandertal variants. Therefore, although autistic people have lower reproductive rates on average, their nonautistic (though potentially still neurodivergent) family members may also be helping to keep this DNA in the gene pool. In other words, even as some evolutionary factors are working to push these autism-related Neandertal-derived genetic variants out of the human genome, other factors are working to retain them.

Although we don’t yet know whether the Neandertal DNA associated with autism is also linked to intelligence, savant­ism or general creativity, we are slowly connecting the dots. If such a relation exists, it suggests that intermixing with Neandertals has affected multiple aspects of brain evolution in our species. In this way, Neandertal DNA is not only a part of the story of autism and other neurodevelopmental and psychological conditions; it’s central to the story of all of us.

Major Depressive Disorder (MDD) disrupts neurological structures and cognitive functions, yet its brain mechanisms remain unclear.

Researchers conducted a retrospective study to assess the impact of MDD on brain activity using electroencephalography (EEG) power spectral analysis and asymmetry metrics.
They obtained EEG recordings from 48 patients with MDD and 78 healthy controls. The data were segmented into 2-second windows (1,024 data points) and analyzed using the Welch method with a Hanning time window and 50% overlap. They calculated absolute and relative power, along with asymmetry values, in the theta, alpha, and beta frequency bands.

The results showed significantly higher absolute and relative power in the theta and beta bands and decreased power in the alpha band in patients with MDD compared to healthy controls. Asymmetry analysis revealed significant differences in the theta band (F7-F8, C3-C4, T3-T4, T5-T6), alpha band (F7-F8, C3-C4, T3-T4, T5-T6, O1-O2), and beta band (C3-C4, T3-T4, T5-T6, P3-P4).

Investigators concluded that MDD alters brain mechanisms and cognitive functions, with theta and beta asymmetry serving as potential biomarkers. The findings supported previous research linking MDD to impairments in memory, attention, and neuroanatomical connectivity.

A study published in 2023 revealed there's a difference in how children with autism or ADHD clear the common plastic additive bisphenol A (BPA), compared to neurotypical children.

BPA is used in a lot of plastics and plastic production processes, and can also be found inside food and drink cans. However, previous research has also linked it to health issues involving hormone disruption, including breast cancer and infertility.

Researchers from Rowan University and Rutgers University in the US looked at three groups of children: 66 with autism, 46 with ADHD, and 37 neurotypical kids. In particular, they analyzed the process of glucuronidation, a chemical process the body uses to clear out toxins within the blood through urine.

They found that kids with ASD and ADHD couldn't clear out BPA and another similar compound called diethylhexyl phthalate (DEHP) with as much efficiency as other kids, potentially leading to longer exposure to their toxic effects.

"Detoxification of these two plasticizers is compromised in children with ASD and ADHD," wrote the researchers in their published paper. "Consequently, their tissues are more exposed to these two plasticizers."

It was only in the case of BPA that the difference was statistically significant though: the efficiency was reduced by about 11 percent for kids with ASD and 17 percent for kids with ADHD, compared with the control group of children.

The researchers think that gene mutations in certain individuals means that BPA can't be cleared as well as it needs to be, which means the substance sticks around in the body. That potentially could cause damage in terms of neuron development and operation.

Conditions like ASD and ADHD are thought to involve a combination of genetic and environmental influences, and this new study brings together both of them. However, it's only part of the story – not every child with a neurodevelopmental disorder had problems flushing out BPA, so there are other factors at play, too.

Work is continuing to identify how exactly ASD and ADHD develop in people – whether it's in utero before birth for example, or later on in life – as the data isn't enough to show whether BPA exposure causes either disorder.

A mom's health during pregnancy is not likely to influence her child's risk of autism, a new study argues.

Many previous studies have reported such a link, but researchers say nearly all these associations can be explained by other autism risk factors -- genetics, pollution exposure, access to health care and the like.

"Our study shows that there is no convincing evidence that any of these other diagnoses in the mother can cause autism," senior researcher Magdalena Janecka, an associate professor of child and adolescent psychiatry at NYU Grossman School of Medicine in New York City, said in a news release.

"Many mothers of children with autism feel guilty about it, thinking that they did something wrong during pregnancy, and it is heartbreaking," Janecka said. "I think showing that these things are not going to cause autism is important and may lead to more effective ways to support autistic children and their families."

For the study, researchers analyzed more than 1.1 million pregnancies among 600,000 mothers listed in a national registry in Denmark.

The team used medical records to check each woman for more than 1,700 distinct diagnoses.

They then corrected for health factors that could offer an alternative explanation for the purported link between a pregnant woman's health and her child's autism.

After accounting for these confounding factors, the team found that 30 diagnoses among mothers were still statistically associated with autism in children. For example, it appeared as though diabetes increased autism risk by 19%, and depression by 49%.

But researchers then compared children with autism to their siblings, to test if these health problems in mom happened alongside autism rather that causing it.

If a mom had the same health problems during pregnancies of children with and without autism, that would suggest factors other than her illness were influencing her child's risk of autism, researchers reasoned.

For example, genetics related to depression are closely tied to those of autism, researchers noted. A woman suffering depression during pregnancy likely shares genes with her child that cause both depression and autism, rather than depression somehow affecting the fetus and causing autism.

After accounting for such familial factors, the only maternal diagnosis still associated with autism was pregnancy complications related to the fetus, researchers found.

“Our interpretation is that these fetal diagnoses likely do not cause autism, but are instead early signs of it," Janecka said.

However, researchers noted that their findings should be tested in other groups of people, to verify that a mom's health does not influence autism risk.

In a recent study published in the journal Translational Psychiatry, a group of researchers investigated the relationship between common genetic variants associated with autism and structural variations in white matter among term-born neonates, highlighting potential associations that may contribute to future research on early autism markers rather than serving as definitive biomarkers.

Background
White matter develops rapidly during pregnancy and infancy, forming essential neural connections that support cognition and motor function. Genetic factors play a crucial role in this process, but their exact influence remains unclear.

Advances in neuroimaging now allow researchers to map these early brain changes, shedding light on how genetic predisposition shapes neural pathways. Understanding these links may lead to earlier interventions, improving outcomes for children at risk of autism.

While studies have explored white matter differences in older children, little is known about how genetic variants influence neonatal brain structure, necessitating further investigation.

About the Study
The present study analyzed white matter structures in 221 term-born infants of European ancestry from the Developing Human Connectome Project. Advanced diffusion-weighted imaging was used to capture high-resolution brain scans, allowing researchers to examine microscopic fiber density and macrostructural morphology. Data preprocessing included noise reduction, motion correction, and normalization to a study-specific brain template.

Genetic analysis involved saliva samples collected at birth or 18 months, which were processed to identify common genetic markers associated with autism. Quality control measures ensured data reliability, excluding samples with incomplete genetic information. Polygenic scores, representing cumulative autism risk, were calculated based on genome-wide association studies and adjusted for ancestry differences.

Statistical models assessed the relationship between genetic risk and white matter structure, accounting for variables such as total brain volume, gestational age, and sex. A gene-set enrichment analysis was conducted to identify biological pathways linked to white matter alterations associated with autism. Additional analyses were performed to explore whether specific genetic pathways influenced structural differences in white matter connectivity.

Study Results
Infants with higher autism polygenic scores showed a significant increase in fiber-bundle cross-section in the left superior corona radiata, a brain region crucial for motor and cognitive functions. This suggests that genetic predisposition to autism may shape early white matter organization, though further studies are needed to confirm its significance for later developmental outcomes.

Further analysis indicated that microscopic white matter properties remained unchanged, while macrostructural differences were prominent in the superior corona radiata and related tracts. These findings align with previous studies reporting increased white matter volume in infants and toddlers later diagnosed with autism. However, the study did not find significant microstructural differences, suggesting that the observed changes are more related to fiber bundle cross-section rather than density or organization at the microscopic level.

A deeper investigation into brain connectivity patterns revealed that infants with higher autism polygenic scores had increased cross-sectional areas in additional white matter tracts, including pathways involved in sensorimotor and cognitive processing. These changes could play a role in the atypical brain connectivity observed in individuals with autism.

Genetic pathway analysis revealed that the autism-associated variants linked to white matter changes were overrepresented in genes related to neuronal connectivity and synaptic function. Notably, genes such as MAPT, KCNN2, and DSCAM—previously implicated in autism risk—were highlighted in the study, reinforcing the hypothesis that white matter alterations are linked to neurodevelopmental processes essential for cognitive and motor function.

While statistically significant, the effect sizes were small, and some findings—such as those related to the right superior corona radiata—did not survive multiple testing corrections, indicating the need for further validation.

These findings suggest that white matter alterations in neonates reflect genetic influences on early brain development rather than serving as definitive biomarkers for autism. If validated in larger studies, these results could have profound implications for early screening and intervention strategies, enabling proactive developmental support before behavioral symptoms emerge.

Conclusions
To summarize, these findings emphasize the profound impact of genetics on early brain development. By identifying structural brain differences at birth, researchers move closer to understanding autism’s earliest origins.

Detecting these alterations early could contribute to research on personalized interventions, allowing for targeted therapies before behavioral symptoms emerge. However, the study does not suggest that current neuroimaging techniques can reliably predict autism in neonates. As neuroscience advances, integrating genetic insights with neuroimaging may help predict neurodevelopmental outcomes, ultimately improving the lives of individuals with autism and their families.

Future research should explore how these early structural changes relate to long-term cognitive and behavioral development, shaping new strategies for early intervention and support.

Infection with whooping cough in infants increases their risk of developing autism spectrum disorder, according to a new study led by scientists at Trinity College Dublin (TCD).

Although the researchers identify whooping cough – also known as pertussis – as a risk factor for autism in a study published by iScience, they say it’s difficult to pinpoint the precise risk involved.

“It is impossible to put a number on this, or to define how much is down to whooping cough,” said immunologist Prof Kingston Mills, who supervised the research led by Dr Eoin O’Neill along with Prof Marina Lynch.

“There have been a few reports showing associations between viral or bacterial infections in pregnancy and autism in offspring,” Prof Mills said.

Whooping cough is a highly infectious bacterial disease affecting the respiratory tract.

“Furthermore, children that have recovered from severe pertussis as infants often have neurodevelopment defects and learning difficulties.

“This is the first report to show a direct link between infection and development of ASD and the first to provide mechanistic insight,” he added.

Meanwhile, scientists also know autistic children are more likely to have had neonatal or early childhood infections compared with the general population.

“We showed that early in life, when the immune system is still immature infection with whooping cough is not confined to the respiratory tract, and bacteria spread to the brain,” he said.

“This results in inflammation in the brain, which negatively impacts immune cells that have a positive effect on neurons. This infection-induced inflammation gives rise to neurodevelopment defects, which results in ASD-like behaviours later in life.”

In Sweden, he said, there was a steep rise in whooping cough incidence between 1984 and 1994 after pertussis vaccination programme was halted which was associated with an increase in ASD numbers.

“The resumption of the pertussis vaccination programme in Sweden in the mid 1990s, following the development of a new pertussis vaccine, was associated with a decline in the prevalence of ASD at a time of global increases in the incidence of autism,” he said.

“This abrupt fall in ASD rates contrasted markedly with worldwide trends during the same period, confounding expected increases in ASD recognition, diagnosis and reporting over time.”

“Vaccination against whooping cough in pregnancy should not only prevent pertussis in the neonatal offspring, who are most susceptible to severe disease, but may also reduce the possibility of developing ASD later in life,” said Prof Mills, who is working on developing a new pertussis vaccine that will be delivered nasally.

Once translated to humans this vaccine holds hope of eliminating community spread of bacteria that has been resurgent in recent years, he said. “It also holds hope of reducing the indigence of neurodevelopment and learning defect seen in children that have recovered from whooping cough.”