'Nothing About Us, Without Us': Research Priorities for Autistic Girls, Women and Gender Diverse People in Australia.

Autistic girls, women and gender diverse people have specific needs that are underrepresented in research. Research priorities are often established by funding bodies, researchers, parents, carers and health professionals and may not meet the needs of the diverse Autistic community. This co-produced project aimed to identify what research would benefit the lives of Autistic girls, women and gender diverse people in Australia. We interviewed 47 Autistic girls, women and gender diverse people aged seven and above and obtained feedback from an additional 411 Autistic people through an online survey. Autistic young people identified six key research priorities including (1) better understanding and support at school, (2) understanding our experiences, strengths and challenges, (3) autism specific mental health support, (4) Autistic friendships and relationships, (5) experiences of gender diversity and (6) accommodations to make life easier for us. Eight key research priority areas were identified by Autistic adults including (1) understanding and supporting specific needs in adulthood, (2) experiences of trauma, abuse and sexual violence, (3) supporting mental health and wellbeing, (4) addressing barriers in healthcare, (5) understanding and supporting physical health needs, (6) addressing barriers in education and the workplace, (7) understanding the role of society, embracing neurodiversity and the importance of Autistic identity and (8) co-designing research and supports with Autistic people. We provide a discussion around the importance of focusing on these research priority areas in future autism research in Australia.

Perceived misdiagnosis of psychiatric conditions in autistic adults.

Background: Many autistic people, particularly women, do not receive an autism diagnosis until adulthood, delaying their access to timely support and clinical care. One possible explanation is that autistic traits may initially be misinterpreted as symptoms of other psychiatric conditions, leading some individuals to experience misdiagnosis of other psychiatric conditions prior to their autism diagnosis. However, little is currently known about the frequency and nature of psychiatric misdiagnoses in autistic adults. Methods: Using data collected in the first half of 2019 from an ongoing longitudinal register of autistic adults in the Netherlands, this study explored the frequency of perceived psychiatric misdiagnoses before receiving an autism diagnosis. Gender differences were also explored. A sample of 1211 autistic adults (52.6% women, mean age 42.3 years), the majority of whom were Dutch and relatively highly educated, was evaluated. Findings: Results showed that 24.6% (n = 298) of participants reported at least one previous psychiatric diagnosis that was perceived as a misdiagnosis. Personality disorders were the most frequent perceived misdiagnoses, followed by anxiety disorders, mood disorders, chronic fatigue syndrome/burnout-related disorders, and attention-deficit/hyperactivity disorder. Autistic women (31.7%) reported perceived misdiagnoses more frequently than men (16.7%). Women were specifically more likely than men to report perceived misdiagnoses of personality disorders, anxiety disorders, and mood disorders. Women also reported prior psychiatric diagnoses more often in general (65.8% versus 34.2% in men). Within the group of individuals with a prior diagnosis, perceived misdiagnoses were equally likely for men and women. Interpretation: One in four autistic adults, and one in three autistic women, reported at least one psychiatric diagnosis, obtained prior to being diagnosed with autism, that was perceived as a misdiagnosis. Inaccurate diagnoses are linked to long diagnostic pathways and delayed recognition of autism. These findings highlight the need for improved training of mental health practitioners, in order to improve their awareness of the presentation of autism in adulthood and of the complex relationship between autism and co-occurring conditions. The current study constitutes a first step towards showing that autistic adults, and particularly women, may be at greater risk of experiencing misdiagnoses. Future studies based on larger, more representative samples are required, to replicate current findings and provide more reliable estimates of the overall frequency of misdiagnoses as well as the frequency of misdiagnoses for specific psychiatric conditions. Funding: This study was made possible by funding from the Netherlands Organisation for Health Research and Development (ZonMW), project number 60-63600-98-834.

Predicting Communication Skills Outcomes for Preschool Children with Autism Spectrum Disorder Following Early Intervention.

Purpose: This study aims to assess changes in the receptive and expressive language skills and to determine if the baseline characteristics such as communication, cognitive and motor skills, predict outcomes in preschool children with Autism Spectrum Disorder (ASD) following early intervention. Methods: We recruited 64 children participating in the Early Start Denver Model (ESDM) early intervention program at an Autism Specific Early Learning and Care Center (ASELCC) in Australia. Baseline characteristics across various developmental domains was measured using the Mullen Scales of Early Learning (MSEL), Vineland Adaptive Behaviour Scales, 2nd Edition (VABS-II), and the ESDM Curriculum Checklist. Linear mixed-effects models were used to examine the effects of the intervention on outcomes. Fixed-effects such as time, groups (verbal and minimally verbal), and time-by-group interactions were assessed whilst adjusting for covariates. Further, multiple linear regression models were used to determine if the baseline characteristics were significant predictors of the outcomes following the early intervention. Results: Among the 64 children who participated in this study, 38 children were verbal, whereas 26 were deemed to have minimal verbal skills. The mean age of the sample was 4.1 years with a significant male predilection (83%) and from a culturally and linguistically diverse (CALD) background (64%). Findings of the linear mixed effects model showed significant within and between group differences in the ESDM subscales, indicating higher magnitude of changes in the verbal group compared to the minimally verbal group. Finally, the multiple linear regression models suggested that baseline MSEL visual reception and expressive language scores were predictive of changes in the ESDM receptive and expressive communication scores. Conclusion: Understanding a child's baseline skill levels may provide valuable clues regarding what interventions would work best, or which interventions may be less suitable for individual preschool-aged children with ASD.

'Living in a world that's not about us': The impact of everyday life on the health and wellbeing of autistic women and gender diverse people.

BACKGROUND: Autistic women and gender diverse people have specific needs related to their physical and mental health. They also experience more barriers to accessing services. While there are autobiographical accounts of the 'invisible' challenges that autistic women and gender diverse people face day-to-day, there has been limited research that explores how these experiences impact health and wellbeing. OBJECTIVES: This study aimed to understand the everyday experiences of autistic women and gender diverse people, and their impact on health and wellbeing. DESIGN: Qualitative methods were used to elicit rich information about the unique experiences of autistic women and gender diverse people. METHODS: We conducted semi-structured interviews with 31 autistic adults. The data were analysed using reflexive thematic analysis. RESULTS: We identified 3 themes and 10 subthemes. Our first theme described 'all the stuff that you have to do to get through life', including managing domestic tasks, parenting, unique health needs and co-occurring physical conditions. The second theme outlined the impact of 'living in a world that's not about us', describing how navigating the neurotypical world, managing gender role expectations and trying to fit impacts on mental health. Our third theme outlined the positive impacts of 'shedding all the layers and being myself', including the importance of formal identification, exploring autistic identity and community, and including autistic people in research to support them to 'have a good life on their own terms'. CONCLUSION: This study emphasized the importance of shifting the responsibility of health and wellbeing from the individual, and the importance of interpersonal, community, cultural, policy and societal factors in ensuring positive health outcomes for autistic women and gender diverse people. It also highlighted areas that enable autistic women and gender diverse people to flourish, including autistic community connectedness, positive relationships and autistic-affirming support from health professionals.

Influencing Best Practices for Genomic and Germline Testing in Urology.

INTRODUCTION: We evaluated germline and somatic testing practices and compared results from tissue and liquid biopsy specimens in a large community urology setting. METHODS: A retrospective analysis was performed on advanced prostate cancer patients from a single community practice between June 2016 and September 2021. Clinical data and sequencing results from tissue and liquid biopsy specimens were available for 389 patients. Genomic data were available for 81 tissues and 74 liquid biopsy specimens. Comparison of genomic findings included 81 tissues and 27 liquid biopsy specimens. The number of actionable biomarkers and patients screened and enrolled in clinical trials was assessed from germline and somatic testing. Frequency of pathogenically altered genes, alteration types, and biomarkers were assessed from tissue and liquid specimens. Alteration frequency was compared between specimen types for the top 25 altered genes. RESULTS: Clinically relevant alterations were found from germline and somatic testing in both tissue and liquid biopsy specimens. The frequency of microsatellite instability-high, tumor mutational burden-high, or alterations in homologous recombination repair genes was consistent with published findings. Concordance between tissue and liquid findings varied with low circulating tumor DNA. CONCLUSIONS: Germline and somatic testing is critical for treatment decisions and should be standard of care for community practices. Liquid biopsy is a viable alternative when circulating tumor DNA is high.

Interactions between the lipidome and genetic and environmental factors in autism.

Autism omics research has historically been reductionist and diagnosis centric, with little attention paid to common co-occurring conditions (for example, sleep and feeding disorders) and the complex interplay between molecular profiles and neurodevelopment, genetics, environmental factors and health. Here we explored the plasma lipidome (783 lipid species) in 765 children (485 diagnosed with autism spectrum disorder (ASD)) within the Australian Autism Biobank. We identified lipids associated with ASD diagnosis (n = 8), sleep disturbances (n = 20) and cognitive function (n = 8) and found that long-chain polyunsaturated fatty acids may causally contribute to sleep disturbances mediated by the FADS gene cluster. We explored the interplay of environmental factors with neurodevelopment and the lipidome, finding that sleep disturbances and unhealthy diet have a convergent lipidome profile (with potential mediation by the microbiome) that is also independently associated with poorer adaptive function. In contrast, ASD lipidome differences were accounted for by dietary differences and sleep disturbances. We identified a large chr19p13.2 copy number variant genetic deletion spanning the LDLR gene and two high-confidence ASD genes (ELAVL3 and SMARCA4) in one child with an ASD diagnosis and widespread low-density lipoprotein-related lipidome derangements. Lipidomics captures the complexity of neurodevelopment, as well as the biological effects of conditions that commonly affect quality of life among autistic people.

The relationship between camouflaging and mental health in autistic children and adolescents.

Camouflaging involves the masking of autistic traits in social situations. While camouflaging may function as a potential barrier to the early diagnosis of autism, minimal research into camouflaging in autistic young people has been conducted. It is also important to evaluate the impact of camouflaging on the mental health of autistic children and adolescents. This study evaluated camouflaging in a sample of 359 female and 374 male autistic children and adolescents (4-17 years, 48.9% females). Findings indicated that camouflaging was a significant predictor of internalizing (i.e., anxiety, depression, somatic complaints) symptoms, when controlling for age, gender, and IQ. We also found evidence for some gender differences in camouflaging. Parents endorsed more autistic traits for females compared with males, whereas there were no differences in autistic traits across sex in the clinician-administered assessment. There was also evidence for a relationship between age and camouflaging, with adolescents showing a larger discrepancy between parent and clinician reported autistic traits. This has implications for clinical assessment and future research and is important for understanding how best to support the mental health of autistic children and adolescents.

Experiences of Performing Daily Activities in Middle-Aged and Older Autistic Adults: A Qualitative Study.

This is the first study to investigate instrumental activities of daily living in older autistic adults. We conducted interviews with fifteen adults (mean age = 60.1, SD = 7.4, range = 50-73) from Australia with no intellectual disability. Analysis included both deductive and inductive steps, to categorise responses using the Occupational Performance Model Australia and identify themes across participants' experiences. Strengths and challenges were unique to the individual, as were the methods they had developed to manage tasks. Challenges occurred mostly at the interaction between aspects of the environment (sensory, cognitive, social and cultural) and personal factors such as health conditions and sensory sensitivities. Enhanced person-environment fit is needed, as is a shift in wider sociocultural attitudes to enable comfort and autonomy in later life.

Patterns of sensory modulation by age and sex in young people on the autism spectrum.

Sensory modulation symptoms form a diagnostic criterion for autism spectrum disorder and are associated with significant daily functional limitations. Utilizing caregiver report on Short Sensory Profile-2 (SSP-2) for 919 autistic children (3-14.11 years), we examined the expression of sensory modulation symptoms by age and sex and investigated the existence of specific sensory modulation subtypes. Sensory modulation symptoms appeared to peak in frequency during middle childhood, particularly in sensory sensitivity and avoidance. Symptoms associated with sensory hypo-reactivity and seeking tended not differ between age cohorts. Males and females demonstrated similar overall sensory modulation profiles, however, females showed elevated symptoms relating to sensory sensitivity. Model-based cluster analysis revealed five interpretable sensory modulation subtypes which related to symptom severity (low, mid-range, high). Subtypes demonstrating mid-range symptom severity differed in focus on sensory hyper-reactivity or seeking symptoms. The findings of this study report for the first time that age-related differences in sensory modulation symptoms may be associated with sensory hyper-reactivity only. The subtyping results also suggest that sensory modulation symptom severity is a reliable means of classifying variance within autistic children, however, consideration of differences in the behavioral strategies employed by individuals to manage sensory modulation symptoms may inform tailored supportive strategies. LAY SUMMARY: We studied sensory symptoms such as over-responding, under-responding and sensation seeking behaviors in 919 autistic children and adolescents. We found that 6-12-year-olds and females displayed the most sensory over-responding symptoms. Autistic children could be grouped into mild, moderate, and severe levels of sensory symptoms, however, children differed in the type of strategies used to cope with their sensory symptoms meaning that they may require different intervention approaches.

Exploring Cultural Differences in Autistic Traits: A Factor Analytic Study of Children with Autism in China and the Netherlands.

Autism spectrum disorders are diagnosed globally, but recognition, interpretation and reporting may vary across cultures. To compare autism across cultures it is important to investigate whether the tools used are conceptually equivalent across cultures. This study evaluated the factor structure of the parent-reported Autism Spectrum Quotient Short Form in autistic children from China (n = 327; 3 to 17 years) and the Netherlands (n = 694; 6 to 16 years). Confirmatory factor analysis did not support the two-factor hierarchical model previously identified. Exploratory factor analysis indicated culturally variant factor structures between China and the Netherlands, which may hamper cross-cultural comparisons. Several items loaded onto different factors in the two samples, indicating substantial variation in parent-reported autistic traits between China and the Netherlands.

The use of everyday and assistive technology in the lives of older autistic adults.

LAY ABSTRACT: Technology has the potential to help people with various support needs live more autonomous lives. This includes autistic individuals. In this article, we look at how older autistic adults use technology in their daily lives. Past research examining technology use and autism has mainly focused on helping children to learn new skills. To date, very little research has been conducted looking at how to create and design technology for use by older autistic adults. This is concerning because older autistic adults will likely have supports needs that match or exceed those of similarly aged non-autistic individuals. In this article, we spoke to autistic adults over 50 years about their daily experiences and how they use technology. We identified some important ways that older autistic adults use technology in their daily lives, as well as a number of support needs and barriers to technology use. Based on the findings, we were able to provide some guidelines and recommendations for technology developers and service providers to assist with designing, creating and using technology with older autistic adults.

Autism-related dietary preferences mediate autism-gut microbiome associations.

There is increasing interest in the potential contribution of the gut microbiome to autism spectrum disorder (ASD). However, previous studies have been underpowered and have not been designed to address potential confounding factors in a comprehensive way. We performed a large autism stool metagenomics study (n = 247) based on participants from the Australian Autism Biobank and the Queensland Twin Adolescent Brain project. We found negligible direct associations between ASD diagnosis and the gut microbiome. Instead, our data support a model whereby ASD-related restricted interests are associated with less-diverse diet, and in turn reduced microbial taxonomic diversity and looser stool consistency. In contrast to ASD diagnosis, our dataset was well powered to detect microbiome associations with traits such as age, dietary intake, and stool consistency. Overall, microbiome differences in ASD may reflect dietary preferences that relate to diagnostic features, and we caution against claims that the microbiome has a driving role in ASD.

Clinical outcomes and associated predictors of early intervention in autism spectrum disorder: a study protocol.

INTRODUCTION: Research highlights the importance of early intervention for children with autism spectrum disorder with better outcomes associated with earlier access to early intensive intervention (EII) programmes. However, there is significant variability in response to EII despite children receiving the same programmes. METHODS AND ANALYSIS: A prospective, multisite cohort study using a pre-post design assesses the predictors of early intervention outcomes for children who receive EII through six early intervention services (Autism Specific Early Learning and Care Centres, ASELCCs) across Australia. Child and family characteristics at entry to and exit from ASELCCs are ascertained using measures of autism symptoms (Autism Diagnostic Observation Schedule-2; Social Communication Questionnaire); cognitive, language and developmental skills (Mullen Scale of Early Learning); adaptive function (Vineland Adaptive Behaviour Scale-second Edition); behaviours (Child Behaviour Checklist-1.5 to 5 years; Restricted Repetitive Behaviour Scale); parental stress (Parent Stress Index-4 Short Form); quality of life (Quality of Life in Autism Scale) and a semistructured family history questionnaire for sociodemographic, family and psychosocial characteristics. Characteristics at entry are used as predictors of outcome at exit following EII approximately 12 months later. The change in score from baseline to exit will be the primary outcome of interest. The mediating role of family and psychosocial factors will also be considered. ETHICS APPROVAL: University of New South Wales Human Research Ethics Committee (HC14267). DISSEMINATION OF RESULTS: Findings will be published in peer-reviewed journals and presented at conferences. A report summarising data and the interpretation of data will be published.

Evaluating the latent structure of the non-social domain of autism in autistic adults.

BACKGROUND: The social domain of autism has been studied in depth, but the relationship between the non-social traits of autism has received less attention. The Diagnostic and Statistical Manual of Mental Disorders (DSM-5) outlines four criteria that make up the non-social domain including repetitive motor movements, insistence on sameness, restricted interests and sensory sensitivity. There is a lack of research into the relationship between these four criteria. This study aimed to evaluate the relationship between the non-social traits of autism in a large sample of autistic adults. It explored whether these traits are best conceptualised as four distinct factors, or exist along a single dimension. METHODS: Participants included autistic adults from the Netherlands Autism Register. The four components identified within the DSM-5 non-social domain were measured by items from the Adult Routines Inventory, the Autism Spectrum Quotient short and the Sensory Perception Quotient short. Confirmatory factor analysis, as well as exploratory factor analysis and exploratory structural equation modelling, was implemented to examine the relationship between these four criteria. RESULTS: Results indicated that a four-factor model provided the best fit, mapping onto the DSM-5 criteria. These four factors were moderately correlated, suggesting that four distinct, yet related factors best describe the non-social domain of autism. The one-factor model did not provide a good fit, highlighting that the non-social domain of autism is not a unitary construct. LIMITATIONS: The study included autistic adults who were cognitively able to complete the self-report measures. This may limit the generalisability of the findings to those who are less able to do so. CONCLUSIONS: This study provided evidence for the multidimensional nature of the non-social domain of autism. Given only two of the four criteria within the non-social domain need to be endorsed for a diagnosis of autism, there is room for substantial variation across individuals, who will have a unique profile within the non-social domain. The results have implications for our understanding of the heterogeneous nature of autistic traits, as well as for how we conceptualise autism as a diagnostic category. This is important for the provision of diagnosis and support within research and clinical practice.

Analysis of common genetic variation and rare CNVs in the Australian Autism Biobank.

BACKGROUND: Autism spectrum disorder (ASD) is a complex neurodevelopmental condition whose biological basis is yet to be elucidated. The Australian Autism Biobank (AAB) is an initiative of the Cooperative Research Centre for Living with Autism (Autism CRC) to establish an Australian resource of biospecimens, phenotypes and genomic data for research on autism. METHODS: Genome-wide single-nucleotide polymorphism genotypes were available for 2,477 individuals (after quality control) from 546 families (436 complete), including 886 participants aged 2 to 17 years with diagnosed (n = 871) or suspected (n = 15) ASD, 218 siblings without ASD, 1,256 parents, and 117 unrelated children without an ASD diagnosis. The genetic data were used to confirm familial relationships and assign ancestry, which was majority European (n = 1,964 European individuals). We generated polygenic scores (PGS) for ASD, IQ, chronotype and height in the subset of Europeans, and in 3,490 unrelated ancestry-matched participants from the UK Biobank. We tested for group differences for each PGS, and performed prediction analyses for related phenotypes in the AAB. We called copy-number variants (CNVs) in all participants, and intersected these with high-confidence ASD- and intellectual disability (ID)-associated CNVs and genes from the public domain. RESULTS: The ASD (p = 6.1e-13), sibling (p = 4.9e-3) and unrelated (p = 3.0e-3) groups had significantly higher ASD PGS than UK Biobank controls, whereas this was not the case for height-a control trait. The IQ PGS was a significant predictor of measured IQ in undiagnosed children (r = 0.24, p = 2.1e-3) and parents (r = 0.17, p = 8.0e-7; 4.0% of variance), but not the ASD group. Chronotype PGS predicted sleep disturbances within the ASD group (r = 0.13, p = 1.9e-3; 1.3% of variance). In the CNV analysis, we identified 13 individuals with CNVs overlapping ASD/ID-associated CNVs, and 12 with CNVs overlapping ASD/ID/developmental delay-associated genes identified on the basis of de novo variants. LIMITATIONS: This dataset is modest in size, and the publicly-available genome-wide-association-study (GWAS) summary statistics used to calculate PGS for ASD and other traits are relatively underpowered. CONCLUSIONS: We report on common genetic variation and rare CNVs within the AAB. Prediction analyses using currently available GWAS summary statistics are largely consistent with expected relationships based on published studies. As the size of publicly-available GWAS summary statistics grows, the phenotypic depth of the AAB dataset will provide many opportunities for analyses of autism profiles and co-occurring conditions, including when integrated with other omics datasets generated from AAB biospecimens (blood, urine, stool, hair).

The Role of Comorbidity on Retention in HIV Care.

Retention is a central component of the Cascade, facilitating monitoring of comorbidity. Country-specific definitions differ and may suit stable and functioning clients, while not appropriately classifying complex clinical presentations characterized by comorbidity. A retrospective file review of 363 people living with HIV attending a Sydney HIV clinic was conducted. Retention was compared with Australian (attendance once/12-months) and World Health Organization (attendance 'appropriate to need') recommendations to identify those attending according to the Australian definition, but not clinician recommendations (AUnotWHO). Multivariable logistic regression analyses determined the impact of age/sex and clinician-assessed comorbidity on retention. Most (97%) participants were considered retained according to the Australian definition, but only 56.7% according to clinician recommendations. Those with psychosocial comorbidity alone were less likely to be in the AUnotWHO group (OR 0.51, 95%CI 0.27-0.96, p = 0.04). The interaction of physical and psychosocial comorbidity was predictive of poor retention (Wald test: χ2 = 6.39, OR 2.39 [95% CI 1.15-4.97], p = 0.01), suggesting a syndemic relationship.

Early Parenting Characteristics Associated with Internalizing Symptoms Across Seven Waves of the Longitudinal Study of Australian Children.

The aim of this study was to identify whether parenting style during a child's toddler years predicts the course of the child's internalising symptoms throughout early to middle childhood. The current study uses data from waves 1 to 7 (acquired biennially) of the infant cohort (N = 4494) of Growing up in Australia: the Longitudinal Study of Australian Children (LSAC), a population-based longitudinal study. Latent class growth analysis identified four distinct longitudinal trajectories of internalizing symptoms: Low stable (66% of the children), High increasing (7%), Low increasing (17%) and High decreasing (10%). Multinomial logistic regression indicated that low self-efficacy and socioeconomic disadvantage during the toddler years were significant predictors of unfavourable (i.e., increasing) trajectories of internalizing symptoms across later childhood. Parenting hostility was a significant predictor of the low increasing trajectory. Additionally, male children were more likely than females to follow unfavourable trajectories. However, low parenting warmth was not predictive of increasing symptoms across time. Our findings highlight the importance of parenting factors in a child's early years, particularly the potentially detrimental outcomes associated with parental hostility and low self-efficacy.

Short report: Social communication difficulties and restricted repetitive behaviors as predictors of anxiety in adults with autism spectrum disorder.

Autism spectrum disorder and anxiety are highly comorbid conditions. Understanding the underlying traits of anxiety in autism spectrum disorder is crucial to prevent and treat it efficiently. Hence, this study determined whether social communication difficulties or restricted repetitive behaviors are stronger risk factors for anxiety symptoms in autistic adults in a large cohort. Data on 742 autistic adults from the Netherlands Autism Register were included in the study. Hierarchical regression was implemented to evaluate whether social communication difficulties (Autism-Spectrum Quotient social behavior factor) and restricted repetitive behaviors (Adult Routines Inventory) were predictive of anxiety (Hospital Anxiety and Depression Scale) controlling for age and sex. When considered together, restricted repetitive behaviors stood out as significant positive predictors of anxiety symptoms (lower-order restricted repetitive behaviors, ß = 0.32, p < 0.001; higher-order restricted repetitive behaviors, ß = 0.15, p = 0.001), whereas social communication difficulties did not (ß = 0.06, p = 0.11). Sex did not moderate these associations (p > 0.05). Non-social autistic traits are stronger predictors of anxiety symptoms than social traits in autistic adults. Increased attention to restricted repetitive behaviors should be given to improve current support programs for autistic adults with anxiety and to identify autistic individuals at risk.

The promise of functional near-infrared spectroscopy in autism research: What do we know and where do we go?

Functional near-infrared spectroscopy (fNIRS) is a neuroimaging technique that has been gaining increasing interest as a method to investigate the brain function of individuals on the autism spectrum. It is a non-invasive, portable and relatively motion-tolerant method of measuring haemodynamic activity in the brain. fNIRS can be particularly effective for quantifying brain function in challenging clinical populations. In light of this, there is a growing body of fNIRS literature focusing on individuals on the autism spectrum. The aim of this review is to evaluate and summarise key studies from the literature and discuss their implications for the field. Potential limitations of the fNIRS approach and resolution of these issues based on emerging fNIRS research are also discussed.