Kelly Barnhill, MBA, CN, CCN, discusses nutrition in autism based on recent publications. She outlines research updates on amino acid patterns, probiotics, and dietary interventions, underscoring both what we know and what we don’t know. The speaker discusses the clinical interpretation and application of this research, touching on common nutrient deficiencies before the Q&A.

In this webinar:

0:00 – Introductions
2:00 – Prospective study on amino acid patterns
5:50 – Prospective Study on Probiotic Intervention
7:40 – Systematic Review of Dietary Intervention and Gut Health
10:54 – Bibliometric Analysis of Influential Articles
13:47 – Systematic Review of Probiotics in Autism
16:06 – Nutrition Reviews Study on Mediterranean Diet
19:28 – Study on Gluten- and Casein- Free Diet
21:48 – Review on Ketogenic Diet
26:16 – Food, Nutrition, and Autism
27:57 – Systematic Review – Food as Medicine
34:40 – Clinical interpretation and application
40:30 – Micronutrients
44:10 – Q&A

Prospective Study on Amino Acid Patterns 

Dr. Barnhill outlines a 2025 study on amino acid patterns in over 1,200 children (2-8 years) with autism. Researchers found lower levels of glutamine in children with autism and significant differences in several amino acids across groups (2:00). Specifically, the study noted that those with neurological impairment were deficient in amino acids that presented with susceptibility to neurocytotoxicity and oxidative stress, while those with nutritional concerns presented with a different set of issues, pointing more toward metabolic concerns. Barnhill explains that these findings substantiate clinical observations and suggest that specific amino acid imbalances may be related to different manifestations of autism, supporting the use of nutritional therapeutic intervention to balance amino acid levels. The speaker emphasizes that this is the only amino acid study presented in a prospective way that has been published in a reputable journal in the past few years. 

Amino Acid Patterns in Children with Autistic Spectrum Disorder: A Preliminary Biochemical Evaluation (Ferraro et al., 2025)

Prospective Study on Probiotic Intervention 

The presenter outlines another recent study that speaks to the concerns of effects of probiotic support for children with autism, AD/HD, and children with both diagnoses (AuDHD) (5:50). Children were given a probiotic or a placebo for three months. Researchers saw a significant improvement in hyperactivity and impulsivity in both the autism and ADHD groups. Most notably, the “comfort score” on a quality-of-life instrument showed significant improvement for autistic children. Barnhill notes that, although this is a small study, its findings support clinical observations that probiotics can improve gastrointestinal symptoms and other related issues in children with autism, potentially impacting their quality of life.

Effect of Probiotics on the Symptomatology of Autism Spectrum Disorder and/or Attention Deficit/Hyperactivity Disorder in Children and Adolescents: Pilot Study (Rojo-Marticella et al., 2025)

Systematic Review of Dietary Intervention and Gut Health 

Barnhill examines a systematic narrative review of all articles published between 2000 and 2024 related to autism, dietary interventions, probiotics, and the microbiome. (25-year review) (7:40). The review validated that dietary intervention can improve GI symptoms and gut health for children with autism, which in turn improves their quality of life. Researchers also identified a cycle where sensory processing issues lead to food avoidance (ARFID), which decreases microbiome diversity and increases harmful microbial species, leading to a neuroinflammatory process that affects behavior (9:12). The speaker asserts that this review provides a strong rationale for addressing GI and microbiome concerns as part of a comprehensive care plan for individuals with autism.

Unraveling the Connections: Eating Issues, Microbiome, and Gastrointestinal Symptoms in Autism Spectrum Disorder (Tomaszek et al., 2025)

Bibliometric Analysis of Influential Articles 

The speaker highlights another 25-year study that reviewed all publications on microbiome treatment in autism since 2000 to identify the most impactful and cited articles (10:54). This is one of the first in a series of bibliometric analyses. The study identified two landmark publications: a 2013 mouse model study that established the link between the gut microbiome and ASD, and a very early, relatively small study from 25 years ago that showed improvements in both GI symptoms and behavior in a small group of autistic children treated with an oral antibiotic. These two studies, along with many more, laid the groundwork for the growing field of gut-brain research in autism and further validated the clinical utility of targeting gut health.

Influential articles in autism and gut microbiota: bibliometric profile and research trends (Ying et al., 2025)

Systematic Review of Probiotics in Autism 

Barnhill discusses a systematic review that analyzed 10 completed and published clinical studies, as well as 18 ongoing clinical trials, on the use of probiotics in autism. (13:47). Reviewers found that probiotics can improve social behaviors, drastically improve GI symptoms, and positively alter the gut microbiome when used appropriately. The presenter emphasizes this paper as a valuable and easily accessible resource for clinicians and parents, as it provides research backing for the use of probiotics in addressing a range of symptoms beyond just GI issues – essentially describing what we’ve learned and why it’s important.

Probiotics in autism spectrum disorders: a systematic review of clinical studies and future directions  (Barba-Vila et al., 2025)

Nutrition Reviews Study on Mediterranean Diet

Barnhill notes that we are seeing more and more solid research emerging about how dietary intervention benefits individuals across the board, highlighting that there is no one-size-fits-all approach for any of us and what that means for clinical applications. She outlines a 2025 evaluation of all studies on children (6-16 years) with autism and ADHD, examining responses to nutritional interventions (16:06). The paper concluded that 70% of individuals who followed a Mediterranean diet showed significant improvement in ADHD symptoms. It also noted significant improvements in depression (80%) and anxiety (50%). The speaker states that these results suggest that focusing on a whole, unprocessed Mediterranean-style diet can be a profound and effective intervention for improving neurological and mental health symptoms. 

Mediterranean Diet and Mental Health in Children and Adolescents: A Systematic Review (Camprodon-Boadas et al., 2025)

Study on Gluten- and Casein-Free Diet

The speaker outlines another 2025 study that evaluated a 12-week trial involving 80 children (4-10 years), using a strict, prescribed gluten- and casein-free diet in combination with and separate and distinct from a neurodevelopmental physical therapy program (19:28). Barnhill notes that families prepared meals on their own, meaning there was no technical control group. Researchers saw significant gains in gross motor skills and cognitive function only when the diet was combined with the therapy program. The dietary group alone showed no significant changes. This study suggests that a multidisciplinary, holistic approach is key, and that dietary interventions may be more effective when combined with other therapies.

Effect of Therapeutic Diet Along with Special Physiotherapy Program on Gross Motor Development and Cognitive Function in Autistic Children: A Randomized Controlled Trial (Alsayegh et al., 2025)

Review on Ketogenic Diet

A review of all published papers on the ketogenic diet for individuals with autism found that the diet is not appropriate for everyone due to the high heterogeneity of autism. However, Barnhill continues, it does hold great potential for some individuals by reducing bacterial dysbiosis, decreasing pro-inflammatory cytokines, enhancing gut health, and providing a neuroprotective effect via ketone bodies (21:48). Barnhill underscores that while the ketogenic diet can be effective for the right patient, it should only be implemented with professional guidance due to its complexity and potential dangers when applied inappropriately. More research is needed.

Exploring the potential of the ketogenic diet in autism spectrum disorder: metabolic, genetic, and therapeutic insights (Schrickel et al., 2025)

Food, Nutrition, and Autism

The presenter provides a summary article describing our current understanding of nutrition and autism from a societal and cultural perspective. The paper tangentially addresses all the issues that people in the US should be aware of and attuned to, including environmental and food exposures from prenatal to childhood. Barnhill asserts this study is foundational for building an appropriate dietary approach and understanding what barriers might exist (26:16). 

Food, nutrition, and autism: from soil to fork (Shepard et al., 2024) 

Systematic Review – Food as Medicine

The speaker notes a recent systematic review that addresses the use of dietary intervention and therapeutic nutritional support across various diagnoses (27:57). The authors highlight several publications that support the idea that food can be considered a form of medicine and is increasingly understood as a pharmaceutical component in health and medical diagnoses. Barnhill emphasizes the importance of not viewing food choices and dietary recommendations for autism as “other” to the general population’s nutritional understanding. Culturally, we continue to recognize that our diets are integral to health and need to be taken seriously. She states that “we need to hold autism research and interventions to the same standards.” This study ultimately resolidifies the interconnectedness of the gut and brain by highlighting the impact of microbiome health in the GI system on both the vagal nerve and cognition (31:00). 

Nutraceuticals in Psychiatric Disorders: A Systematic Review (Bozzatello et al., 2024)

Clinical interpretation and application

According to the presented information, Barnhill asserts that clinicians should assume that diet matters and that a nutritionist or dietary specialist should be included in care counseling and planning for children and adults with autism (34:40). She underscores the importance of avoiding packaged food products, ensuring fiber and water intake are sufficient, and addressing feeding concerns with care and compassion. She also suggests incorporating family and community into diet changes, meal preparation, and eating habits. The speaker also suggests working with a professional to outline any specialized diets (37:40). 

Micronutrients & Therapeutic Support

Barnhill lists common micronutrient deficiencies, including B vitamins, fat-soluble A and D, and Omega-3 fatty acids. She notes that addressing gaps with supplemental support is reasonable and appropriate to meet the minimal needs in the case that someone doesn’t have access to those nutrients via diet (40:30). She cautions viewers about the supplement market, noting that it is not regulated; and suggests consulting with someone well-versed in what’s needed and the efficacy of different brands before the Q&A (44:10). 

James McPartland, Ph.D., discusses current limitations in autism diagnosis and treatment, noting their reliance on behavioral observations despite the condition’s genetic and neurological underpinnings. He advocates integrating biomarkers as objective, measurable biological indicators that revolutionize clinical practice. The speaker details ongoing research into the N170 biomarker, its connection to social behavior and development, and potential for measuring intervention efficacy. McPartland outlines the collaborative work of the Autism Biomarkers Consortium for Clinical Trials (ABC-CT) and its implications for autism diagnosis and care.

Handouts are online HERE

In this webinar:

5:00 – The need for biomarkers in autism
11:00 – Practical considerations for clinical practice
13:30 – EEGs as a promising biomarker technology
20:00 – The N170 biomarker
28:00 – N170: social and behavioral development
34:00 – Confounds and responses to behavioral interventions
42:00 – Autism Biomarkers Consortium for Clinical Trials (ABC-CT)
47:00 – ABC-CT progress and impact
54:00 – Implications for clinical practice

The need for biomarkers in autism

highlighting that these methods have remained largely unchanged since the initial descriptions in 1943 (5:00). Although today we understand that autism is rooted in genetics and the brain, there are no biological assays—meaning no tests to aid in diagnosis, guide treatment selection, or measure intervention effectiveness. He explains that this lack of biological criteria impedes our ability to provide optimal care (8:17).

The presenter details various categories of biomarkers as defined by the FDA, each serving a distinct “context of use” or purpose:

• Diagnostic biomarkers are used to identify the condition.
• Susceptibility or risk markers can indicate the likelihood of developing autism.
• Pharmacodynamic or response biomarkers show changes in response to treatment.
• Prognostic biomarkers help to predict the course of development.
• Predictive biomarkers estimate response to specific treatments.
• Stratification biomarkers are used to subgroup the highly heterogeneous autistic population meaningfully. This last category, McPartland suggested, represents the “lowest hanging fruit” for immediate impact in autism.

Practical considerations for biomarker adoption in clinical settings include viability across the diverse autism population, cost-effectiveness, and accessibility (11:00).

EEG as a promising biomarker technology

McPartland presents various methods for measuring brain activity in autism, including electroencephalography (EEG), fMRI, PET scans, and eye tracking. He highlights EEG as an ideal technology that detects electrical activity produced by brain cells from the scalp. This technology offers many advantages, especially that it is non-invasive, movement tolerant, widely applicable, cost-effective, and accessible, as they are widely available in hospitals. EEGs have also been used effectively to understand social communicative development, supporting their use in autism research (13:18). The speaker notes the wide variability in clinical presentations of autism and the challenges this presents in using biomarkers for diagnostic purposes (18:00). 

The N170 biomarker and its Implications

The speaker describes the N170, an event-related potential (ERP) component measured by EEG. The N170 is a negative electrical spike that occurs around 170 milliseconds after seeing a human face. This indicates the brain’s rapid recognition of a face as a face, making it highly relevant to social communication (20:00). McPartland outlines a 2004 study that compared the N170 in autistic and allistic (non-autistic) adolescents and adults. Preliminary findings show that autistic participants exhibited a slower N170 response, which was replicated in a younger cohort. These findings, the speaker asserts, suggest a difference at the fundamental stages of face perception (22:30). Further research showed that the N170 latency correlated directly with impaired facial recognition abilities in autistic participants, providing crucial evidence that the N170 is not simply a brain anomaly, but a biomarker associated with a clinically relevant social function.

Event-related brain potentials reveal anomalies in temporal processing of faces in autism spectrum disorder (McPartland et al., 2004)

A biomarker for social behavior and development

To determine if the N170 response is meaningfully tied to social behavior, subsequent research by McPartland and colleagues compared brain responses to faces (social), letters (non-social, an autistic strength), and houses (control). Results indicated the N170 latency is specific to social stimuli, where similar slowness was not observed in response to letters (28:00). The only difference for letters was a tendency for autistic individuals to involve more of the right hemisphere, typically associated with faces (a difference in lateralization). These findings, the presenter asserts, confirm the N170 biomarker’s specificity to the social domain in autism, rather than a general indicator of slower sensory processing. As the findings were replicated in a younger cohort, this study also provides evidence of the N170 biomarker’s relevance to development (32:00). 

Atypical neural specialization for social percepts in autism spectrum disorder (McPartland et al., 2011)

Confounds and responses to behavioral interventions

McPartland briefly touches on research addressing confounds, such as eye gaze patterns. A 2021 study indicated that the N170 differences persisted even when eye gaze was experimentally controlled. This suggests that the brain difference is fundamental and not simply a consequence of where someone is looking, thus strengthening the validity of the N170 as a robust measure of underlying neural processes (34:00). Studies also show that the N170 biomarker may be sensitive to changes in clinical status following behavioral interventions. The speaker explains that this suggests potential for N170 to serve as a response biomarker, capable of measuring the effectiveness of therapeutic interventions (36:00). 

The N170 event-related potential reflects delayed neural response to faces when visual attention is directed to the eyes in youths with ASD (Parker et al., 2021)

Brief Report: Preliminary Evidence of the N170 as a Biomarker of Response to Treatment in Autism Spectrum Disorder (Kala et al., 2021)

Social attention: a possible early indicator of efficacy in autism clinical trials (Dawson et al., 2012)

Brain mechanisms of plasticity in response to treatments for core deficits in autism (Ventola et al., 2013)

Large-scale autism biomarkers consortium for clinical trials 

The presenter outlines the Large-Scale Autism Biomarkers Consortium Study, or the Autism Biomarkers Consortium for Clinical Trials (ABC-CT), a monumental effort to bridge the gap between scientific discovery and clinical application in autism. The overarching goal of the ABC-CT is to accelerate the development of effective treatments for social impairment in autism by identifying, developing, and validating a set of reliable, objective, and quantitative measures that can serve as biomarkers (42:00). McPartland notes the rationale for this multicenter research study, highlighting its potential for bridging the research-to-clinic gap. 

The main study is longitudinal, tracking participants between 6 and 11 years old across multiple time points to evaluate candidate biomarkers’ stability and sensitivity to change. A battery of measures was collected, including clinician and caregiver assessments, biospecimens (DNA samples), and lab-based measures like EEG, eye tracking, and behavior observations (45:00). The ABC-CT specifically investigates well-evidenced candidate biomarkers, such as N170. Candidate biomarkers must meet several criteria, including feasibility and construct validity.

Identifying Age Based Maturation in the ERP Response to Faces in Children With Autism: Implications for Developing Biomarkers for Use in Clinical Trials (Webb et al., 2022)

The Autism Biomarkers Consortium for Clinical Trials: Initial Evaluation of a Battery of Candidate EEG Biomarkers (Webb et al., 2023)

Progress and impact

To date, the ABC-CT reports high levels of successful data acquisition and acceptance of the N170 latency in upright human faces. Therefore, the FDA views the N170 as a promising stratification (subgrouping) biomarker for clinical trials. An eye-tracking biomarker has also been submitted, the Oculomotor Index of Orienting to Human Faces (47:00). In 2020, ABC-CT was renewed for a follow-up study to evaluate long-term stability, sensitivity to change, and longitudinal predictive value in the original cohort. Data collection occurred from May 2021 to August 2022, and a confirmation study was completed in March 2025. A feasibility study was also launched in August of 2024 (49:00). McPartland underscores the importance of increasing inclusivity in neuroscience studies, specifically of autistic people with intellectual disabilities. He presents N170 latency replication studies in this group (50:30). 

Implications for clinical practice

The speaker reiterates the potential impact of ABC-CT as a collaborative effort to develop objective tools that can address the heterogeneity of autism, improve the design and efficiency of clinical trials, and ultimately lead to more personalized and effective treatments for autistic individuals. He reiterates that rigorous study of biomarkers like the N170 holds immense implications for improving clinical understanding and care for autistic individuals via subgrouping, measurements of treatment effectiveness, earlier identification, and enhanced clinical trials (54:00). The presenter asserts that a biomarker’s utility is a “moving target,” evaluated for its purpose in a particular situation. The ongoing research into the N170 and other biomarkers represents a critical step towards a future where objective biological measures significantly enhance clinical understanding and intervention for autism. McPartland provides thanks and acknowledgments before the Q&A (55:02). 

Originally published November 4, 2024

Francesca Solmi, Ph.D., discusses the intricate link between autism and eating disorders. She outlines common eating disorders, noting their overlapping symptoms and similarities to autism traits. The speaker explores potential mechanisms for the connection between eating disorders and autism, including communication difficulties, sensory sensitivities, and emotion regulation. Solmi emphasizes Avoidant/Restrictive Food Intake Disorder (ARFID) and its relevance to autism, underscoring the need for more research and services for this often overlooked condition. The presenter considers future research directions before the Q&A.  

Handouts are online HERE

In this webinar:

1:30 – Common eating disorders
8:00 – Autism and eating disorders
11:00 – Trajectories of autistic traits and eating disorders
20:00 – Potential linking mechanisms
28:00 – Emotion regulation
34:50 – Avoidant/Restrictive Food Intake Disorder (ARFID) and Autism
40:00 – Future research
42:00 – Q&A

Overview of Eating Disorders 

Solmi defines eating disorders as severe psychiatric conditions that typically emerge in early to mid-adolescence. She describes common eating conditions, including Anorexia Nervosa, Bulimia Nervosa, Binge Eating Disorder, and OSFED (Other Specified Feeding or Eating Disorder), highlighting the significant symptom overlaps across conditions (1:35).

• Anorexia Nervosa – frequently the youngest age of onset. Characterized by an intense fear of weight gain, extreme dietary restriction, and often low body weight. Some individuals may also engage in bingeing and purging.
• Bulimia Nervosa – slightly later onset and involves episodes of binging followed by compensatory behaviors like self-induced vomiting or excessive exercise.
• Binge Eating Disorder – the most recently recognized diagnosis. It involves bingeing without compensatory behaviors, often accompanied by feelings of shame or guilt.
• OSFED (Other Specified Feeding and Eating Disorder) is a residual category for individuals whose symptoms don’t fully meet the criteria for other diagnoses. 

The speaker emphasizes the severity of these conditions, noting their association with higher mortality rates (5:00). Despite this, eating disorders are often under-researched compared to other mental health disorders. She also notes their high prevalence in girls and women, suggesting underdiagnosis in men (6:30).  

The Link Between Autism and Eating Disorders 

Solmi discusses the connection between autism and eating disorders. A study by Westwood and colleagues revealed elevated autistic traits in people with anorexia nervosa. Similarly, people with autism and anorexia nervosa mentioned rigidity or rules, intense interests, difficulties recognizing hunger, and social difficulties (8:00). A significant challenge in this research, the presenter explains, is distinguishing between pre-existing autistic traits and those that may be mimicked by severe malnutrition in anorexia nervosa. 

Autism Spectrum Disorder in Anorexia Nervosa: An Updated Literature Review (Westwood et al., 2016)

Research on Autistic Traits and Disordered Eating Trajectories

Solmi presents findings from a study investigating whether autistic traits were present before the onset of disordered eating behaviors (11:00). Researchers found that children who later developed disordered eating behaviors exhibited higher levels of autistic traits at age seven, and these differences persisted throughout adolescence. The speaker asserts that these findings suggest autistic traits may precede the onset of disordered eating (17:00). The study also revealed that more severe eating disorder symptoms correlated with higher autistic trait scores from age seven onwards, indicating a strong association with more severe presentations of eating disorders.

Trajectories of autistic social traits in childhood and adolescence and disordered eating behaviours at age 14 years: A UK general population cohort study (Solmi et al., 2020)

Potential Mechanisms Linking Autism and Eating Disorders 

The presenter explores several mechanisms as potential links between autism and eating disorders. For example, as friendships become more important in adolescence, struggles with social interaction can exacerbate mental health difficulties, with eating disorders potentially serving as a coping mechanism. Children with social communication difficulties may also be more susceptible to bullying, which can lead to internalized weight-stigmatizing thoughts and behaviors like dieting (20:00). Young people with autism often exhibit more sedentary behaviors compared to their peers, which can increase BMI and vulnerability to weight-based stigmas (23:00). 

Emotion regulation difficulties are also common in both autism and eating disorders. Solmi outlines a recent study showing that individuals who later developed anorexia nervosa symptoms exhibited less improvement in emotion regulation skills from early to mid-childhood compared to their peers, where differences emerged around age five (30:00). Further, in girls, social cognition explained around half of the association between emotion regulation difficulties and disordered eating. The association in boys was less clear, likely due to smaller sample sizes (35:00).

The presenter notes that sensory sensitivities, a core aspect of avoidant/restrictive food intake disorder (ARFID), are frequently reported by people with anorexia nervosa. For example, in a qualitative study on autism and anorexia in women, emerging themes included difficulty with sensory sensitivities, social interactions and relationships, and challenges with emotions (33:00). 

A mixed-methods approach to conceptualizing friendships in anorexia nervosa (Datta et al., 2021)

Autism Spectrum Disorder and Obesity in Children: A Systematic Review and Meta-Analysis (Sammels et al., 2022)

Emotional dysregulation in childhood and disordered eating and self-harm in adolescence: prospective associations and mediating pathways (Warne et al., 2022)

“For Me, the Anorexia is Just a Symptom, and the Cause is the Autism”: Investigating Restrictive Eating Disorders in Autistic Women (Brede et al., 2020)

Avoidant/Restrictive Food Intake Disorder (ARFID) and Autism

Solmi discusses ARFID, a disorder now included in the eating and feeding disorder family, noting its relevance to autism. Its three main aspects include limited interest in food, sensory sensitivities (e.g., avoiding specific foods due to texture), and concerns about adverse consequences from eating (34:50). The speaker emphasizes the limited epidemiological research on ARFID, the lack of services (especially for people who are not severely underweight), and the need for more studies to understand its prevalence, risk factors, and effective treatments (37:00).

Future Research Directions 

According to the presenter, future research should aim to understand the complex links between autism and eating disorders more comprehensively. Key areas of investigation include the connections between sensory sensitivities and ARFID, gender differences in the association of autistic traits and eating disorders, links between other autistic traits and different eating disorder presentations, physiological factors like the gut-brain response, and age of autism diagnosis in those with and without eating disorders. These avenues of research, Solmi asserts, will improve diagnostic tools and help to develop better prevention and care strategies (40:00). The speaker summarizes main points before the Q&A (42:20). 

April 15, 2025

The prevalence of autism among children in the United States was updated this week, with the latest data from the U.S. Centers for Disease Control and Prevention (CDC) estimating that 1 in every 31 children was diagnosed with the condition in 2022. This marks a continued upward trajectory from the CDC’s prior estimate of 1 in 36 children in 2020.

One report found that 1 in 36 8-year-old children have been diagnosed with autism, according to 2020 data from 11 states.

• The CDC reported shifts in racial and ethnic disparities in autism prevalence – for the first time in years of CDC data collection, non-white children are identified as having autism at higher rates than white children;
• The findings represent a nearly 20 percent increase over the 1 in 44 estimates based on 2018 data;
• As in the past, among racial groups, Black children with autism and co-occurring intellectual disability are identified at significantly higher rates — suggesting that some Black children without intellectual disabilities are too-often missed;
• Autism is nearly four times more prevalent in boys; among girls, prevalence is 1 in 88.

This latest announcement underscores the urgent need to invest in peer-reviewed, biological research about co-occurring conditions and autism and appropriate medical care for individuals across the spectrum. As science continues to reveal the complex and diverse nature of autism, it is clear that targeted funding is urgently needed to support the researchers and clinicians working on the front lines of investigation.

Since 1995, the Autism Research Institute (ARI) has brought together leading experts to explore the biological underpinnings and co-occurring medical conditions associated with autism. We proudly stand with others in the autism community in calling for sustained and meaningful investment in research that safeguards the health of autistic people.

You can help move research forward

You make a difference and help come up with information and solutions that have a direct impact on improving the health and well-being of people with autism. 

Emily Ferguson, Ph.D., discusses self-regulation strategies for self-injurious behaviors (SIB). She outlines recent research on the frequency and distribution of different SIBs across a large sample, underscoring the importance of assessing individual behavior severity instead of an overall SIB score. The presenter considers the role of emotion regulation in SIB interventions. Ferguson considers emotion recognition, coping strategies, and prevention methods and provides free online resources for parents and clinicians.

In this webinar:

2:25 – Self-injurious behavior and autism
7:20 – Study: Frequency and distribution of unique SIBs
10:30 – Results
17:25 – Summary
19:45 – Helpful questions
22:20 – Adult self-reports
24:12 – Dialectical behavior therapy (DBT)
27:00 – Emotion regulation (ER) and challenging behaviors
30:45 – Emotion recognition and ER strategies
33:55 – Prevention
39:30 – Resources
42:40 – Q&A

Self-injurious behavior and autism

Ferguson explains that self-injurious behaviors (SIBs) are present in 40 – 50% of autistic people. They often persist in varying forms and intensities across the lifespan and significantly increase the likelihood of tissue damage or physical injury, hospitalization, and more restrictive residential placements (2:25). Common forms of repetitive behaviors include head-banging, skin-scratching, self-hitting, hair-pulling, lip or cheek-biting, nail-biting, skin-picking, and hitting against hard objects. Research shows that lower speech production, lower cognitive functioning, greater emotion dysregulation, greater sensory sensitivity, sex, and age are all linked to greater severity of SIB (6:30). The presenter notes that measurements and conceptualization of SIB vary across studies (5:25).

Frequency and distribution of unique SIBs

The speaker outlines her recent publication on the frequency and distribution of unique SIBs across a large sample. The study uses 593 survey responses to explore speech level, cognitive function, emotion dysregulation, and sensory sensitivities for each of the eleven most common non-suicidal SIBs (7:20).

Roughly 30-50% of caregivers reported mild to severe concerns for many types of SIB, highlighting the importance of looking at severity for every kind of SIB instead of an overall score. Results show that higher emotion dysregulation, or difficulty managing, responding, or calming strong emotions, was significantly associated with greater severity of nine types of SIB ranging from self-hitting to skin-picking (10:30). Higher sensory hypersensitivity was associated with greater severity of self-scratching (with and without tissue damage), repetitive hair-twirling, and skin-picking and lip-biting (with and without tissue damage). Ferguson asserts these findings indicate that these types of SIB may be a means of self-soothing or communicating distress in response to overwhelming sensory stimuli (13:30).

Self-scratching, self-hitting, and lip-biting (with tissue damage) were significantly associated with lower IQ, suggesting that the presence of intellectual disabilities (ID) might increase the risk of engaging in specific types of SIB. The study also found that youth who speak in full sentences demonstrate lower severity of self-hitting and head-banging than youth who use no words to communicate. Ferguson reiterates that self-hitting and head-banging may be a way of communicating, especially for autistic people with ID who are non-verbal (15:45). 

She summarizes research findings, reiterating the important insights we can gain by examining the severity of unique types of SIB rather than their overall occurrence. She notes that head-banging and self-hitting can result in serious physical harm, posing a greater risk to those with lower IQs and speech ability (17:25). 

The speaker suggests asking these questions to help determine causes and care strategies for SIB (19:45):

• Is the situation placing demands that exceed ER skills? (Adaptive emotion regulation (ER) skills)
• Is the behavior in response to unmet sensory needs or sensory overload? (Sensory dysregulation)
• Are the demands on the individual too high or low for their cognitive level? (Cognitive capacities)
• Does this person have a functional way to communicate? (Adequacy of communication system)

•  Exploring the Heterogeneity of Self-Injurious Behaviors in Autistic Youth: Patterns, Predictors, and Implications for Intervention (Ferguson et al., 2025)

Adult Self-Reports

The presenter outlines a recent study by Moseley and colleagues that asked autistic adults about the perceived role of non-suicidal SIBs (a more extensive list than the previous study). Participants reported hurting themselves in order to feel something, change emotional pain into something physical, relieve stress or pressure, deal with frustration, shock or hurt someone, self-punishment, and to prevent hurting themselves in other ways (22:20). 

• A ‘choice’, an ‘addiction’, a way ‘out of the lost’: exploring self-injury in autistic people without intellectual disability (Moseley et al., 2019)

Dialectical behavior therapy (DBT)

Dialectical Behavior Therapy (DBT) was developed for people with borderline personality disorder but can be applied to people across the spectrum of life. DBT is often a first-line treatment for people who engage in SIB or have suicidal thoughts or tendencies. It works to identify and distinguish repetitive behaviors, accepting the ones that serve a good purpose while changing others that increase the risk of harm to self or others (24:21). 

Emotion regulation and challenging behaviors

The speaker outlines the pathway from difficulties with ER to challenging behavior presentation and considers the role that self-regulation has in SIB interventions (27:00):

 Individual factors (hungry or tired) → precipitating cues (loud/surprising noise) → difficulty identifying and labeling emotions (overwhelmed) →  negative experience continues or increases (no coping strategy) → challenging behavior is expressed.

Emotion recognition

Emotion recognition can be difficult for everyone, and creating a personalized feeling chart can significantly help. Ferguson discusses how to make a feeling chart that captures the sounds and feelings of one’s emotions as well as what someone needs in those moments (30:45). 

Emotion regulation (ER) strategies

ER strategies include coping skills and co-regulation techniques, which the speaker suggests should be practiced daily. For caretakers, it is essential to do these things with their child or patient to model effective coping strategies. Ferguson highlights the benefits of parent skills training and provides a free training video that teaches some quick coping skills for calming down and returning to a place where you can work through problems and big emotions more effectively (31:40). 

• https://www.youtube.com/watch?v=0cq5RuE8SXk

Prevention

SIB prevention techniques focus on reducing the likelihood of distressing situations or contexts. If an SIB consistently occurs in a specific location, consider what about that place may cause distress to you or your child. It’s also helpful to note setting events, like sleep, that can affect irritability and ER throughout the day (33:55). The Research Units in Behavioral Intervention (RUBI) provides free online materials to help with SIB prevention.

• https://academic.oup.com/book/1248/chapter/140180019

Functional behavior analyses of problem behaviors are commonly used to identify antecedents, behaviors, and consequences and can help identify positive and negative communication cycles. Ferguson emphasizes that behavioral approaches must be strengths-based and aimed at reducing negative impact. Other prevention methods include mental health therapies and parent training in behavior management, as outlined in the RUBI resources and Parent-Child Interaction Therapy (ages 2 – 7) (35:55). The speaker shares a clinical guide for treating severe behaviors, toolkits, and ECHO training (39:30) before the Q&A (42:40). 

Resources provided during the talk and in text:

• Article by Dr. Ferguson mentioned in the talk: https://onlinelibrary.wiley.com/doi/full/10.1002/aur.3269
• ECHO Autism Challenging Behavior: https://echoautism.org/challenging-behavior/
• Autism Speaks Challenging Behavior Toolkit: https://www.autismspeaks.org/tool-kit/challenging-behaviors-tool-kit
• RUBI intervention online materials: https://academic.oup.com/book/1248/chapter/140180019
• Moseley article referenced during the talk: https://link.springer.com/content/pdf/10.1186/s13229-019-0267-3.pdf

Originally published December 3, 2024.

Dr. Bradley Ferguson, PhD, a 2024 research grant recipient, discusses emerging research on the interaction of GI symptoms and stress in autism. He outlines recent investigations highlighting the connection between GI issues, cortisol levels, and internal and external behaviors. The speaker discusses electrodermal activity (sweat) as a way to measure and predict problem behaviors and considers the potential for treating stress to alleviate GI symptoms. Ferguson underscores the importance of real-world data and outlines ongoing work funded by ARI, which uses smartwatches to monitor physical and social indicators of stress behavior over three weeks. He describes current hypotheses and potential implications for this work before the Q&A.

In this webinar:

1:30 – Stress and the gut
6:30 – Stress and communication
13:13 – Electrodermal activity
17:20 – Treating the stress response
25:30 – Ongoing work
31:47 – “CORE Autism” smartwatch app
37:45 – Implications
39:35 – Summary
42:00 – Q&A

The gut and stress

The prevalence of co-occurring gastrointestinal (GI) issues in autism ranges from 9 to 91%, with constipation being the most common (1:30). Research shows that many autistic people have a heightened stress response which activates the sympathetic nervous system – fight or flight mode – and inhibits stomach function. Ferguson and his team look at GI issues through a stress lens, suggesting that activation of the sympathetic nervous system is related to a lot of GI issues (3:00). He outlines past work that shows a positive relationship between levels of cortisol, a stress marker, and constipation (4:30). Similar work shows that having co-occurring anxiety significantly altered parasympathetic nervous system activity in the lower GI tract, meaning that anxiety is related to GI symptoms in autism (5:40). 

In a 2019 study, Ferguson and colleagues used caregiver questionnaires for 340 autistic children and adolescents to assess correlations between GI conditions and behavior issues (6:30). Results showed that across all ages, 65% experienced constipation, 50% experienced stomach aches, 29% experienced diarrhea, and 23% experienced nausea, where 53% were taking medications for other conditions (ADHD, seizures), and 93% were not taking any GI meds (9:30). In children between the ages of 1 and 5, nausea significantly predicted aggression. Ferguson says that this correlation is likely to do with the children’s inability to communicate their nausea, which leads them to act out. In participants between 6 and 18 years old, anxiety, withdrawn behavior, and somatic complaints were 11% more likely to experience aggression, stomachaches, and nausea, respectively, and less likely to experience certain other GI symptoms (10:55).

The speaker summarizes research findings to date, highlighting that non-verbal young children may use aggression to communicate somatic complaints and that older children have more internalizing behaviors associated with GI symptoms. 

Associations between cytokines, endocrine stress response, and gastrointestinal symptoms in autism spectrum disorder (Ferguson et al., 2016)

Psychophysiological Associations with Gastrointestinal Symptomatology in Autism Spectrum Disorder (Ferguson et al., 2016)

The Relationship Among Gastrointestinal Symptoms, Problem Behaviors, and Internalizing Symptoms in Children and Adolescents With Autism Spectrum Disorder (Ferguson et al., 2019)

Electrodermal activity and problem behavior

Electrodermal activity, or skin sweat, is part of the stress response triggered by the sympathetic nervous system. Using a smartwatch, researchers were able to track skin conductance (sweat) from baseline to post-behavior levels (13:13). Results showed a rise in sweat about 60% of the time prior to a problem behavior occurring and a return to baseline afterward about 45% of the time. The average rise in skin conductance before a behavior was around 10 minutes (15:15). 

Examining the Association Between Electrodermal Activity and Problem Behavior in Severe Autism Spectrum Disorder: A Feasibility Study (Ferguson et al., 2019)

Treating the stress response

Ferguson and his team assessed a trial of propranolol, a beta blocker (blocks stress response), in children and youth with autism. Results showed a significant reduction in anxiety for the propranolol group compared to controls (17:20). He outlines an fMRI study on the relationship between GI issues and amygdalar activity. The study revealed that participants taking propranolol (which crosses the blood-brain barrier) showed a neutral relationship between GI symptoms and amygdala activity. In contrast, those taking nadolol (which does not cross the blood-brain barrier) or a placebo showed a positive correlation. Ferguson explains that these findings indicate that propranolol is blocking the stress response, which may be related to GI issues (19:25). Future research will include transcutaneous vagus nerve stimulation (tVNS) to test the effect of parasympathetic nervous system (rest and digest) activation on GI symptoms (23:45). 

Ongoing work

The research outlined to this point has been strictly lab-based, and the speaker highlights the need for real-world “ecological” monitoring of stress behavior. Lab studies are often stressful in and of themselves, so they may not reflect real-world functioning. Ferguson’s ongoing study, funded by ARI, aims to examine differences in verbal social communication data from 30 autistic people with GI symptoms and 30 without over a three-week period. Data will be collected using smartwatches that track pulse-rate variability, or the time variation between heartbeats, measured with photoplethysmography (PPG). Researchers will also examine differences in autonomic nervous system functioning in relation to GI symptoms (25:30). 

Verbal and social activity will be recorded on a smartwatch app that Ferguson and his team developed called “CORE Autism (31:47).” The app measures the total time spoken by a participant. It has reached 90% agreement between what researchers hear and what the algorithm hears (35:35). The speaker underscores the importance of real-world data and how much we miss with typical laboratory-based questionnaires. Researchers hypothesize that pulse rate variability will be significantly lower for the group with GI issues, indicating a higher stress response. They also hypothesize that there is less social communication among the GI group, possibly due to increased stress (36:48).

Ferguson emphasizes that findings from this study will provide real-world evidence of stress and sociability, allowing a potentially different take on the connection between GI issues and stress for autistic people. For example, if stress is heightened in the GI group, implications for treatment could be huge. The presenter notes that more research could be done to address what happens to GI symptoms when stress is addressed and vice versa (37:45). This study will be finished in 2026. 

Summary

Ferguson reviews the presentation, highlighting that GI symptoms like constipation are prevalent in autism and often associated with stress response and internalizing behaviors, which may differ by age. The stress response may also precede problem behaviors in autism, providing treatment options based on stress reduction via pharmacological, vagal, and behavioral avenues. While preliminary data are exciting, more research is needed in these areas (39:35). Ferguson provides thanks and acknowledgments before the Q&A, where he discusses enteroception, SSRIs, nutrition, smartwatch usage, and more (42:00). 

Originally published November 19, 2024