Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2025 Jun 4;16(1):33.
doi: 10.1186/s13229-025-00667-z.

Subgrouping autism and ADHD based on structural MRI population modelling centiles

Affiliations

Subgrouping autism and ADHD based on structural MRI population modelling centiles

Clara Pecci-Terroba et al. Mol Autism. .

Abstract

Background: Autism and attention deficit hyperactivity disorder (ADHD) are two highly heterogeneous neurodevelopmental conditions with variable underlying neurobiology. Imaging studies have yielded varied results, and it is now clear that there is unlikely to be one characteristic neuroanatomical profile of either condition. Parsing this heterogeneity could allow us to identify more homogeneous subgroups, either within or across conditions, which may be more clinically informative. This has been a pivotal goal for neurodevelopmental research using both clinical and neuroanatomical features, though results thus far have again been inconsistent with regards to the number and characteristics of subgroups.

Methods: Here, we use population modelling to cluster a multi-site dataset based on global and regional centile scores of cortical thickness, surface area and grey matter volume. We use HYDRA, a novel semi-supervised machine learning algorithm which clusters based on differences to controls and compare its performance to a traditional clustering approach.

Results: We identified distinct subgroups within autism and ADHD, as well as across diagnosis, often with opposite neuroanatomical alterations relatively to controls. These subgroups were characterised by different combinations of increased or decreased patterns of morphometrics. We did not find significant clinical differences across subgroups.

Limitations: Crucially, however, the number of subgroups and their membership differed vastly depending on chosen features and the algorithm used, highlighting the impact and importance of careful method selection.

Conclusions: We highlight the importance of examining heterogeneity in autism and ADHD and demonstrate that population modelling is a useful tool to study subgrouping in autism and ADHD. We identified subgroups with distinct patterns of alterations relative to controls but note that these results rely heavily on the algorithm used and encourage detailed reporting of methods and features used in future studies.

Keywords: ADHD; Autism; Neuroimaging; Population modelling; Structural MRI; Subgrouping.

PubMed Disclaimer

Conflict of interest statement

Declarations. Ethics approval and consent to participate: Ethical approval and informed consent were obtained for each primary study. The Cambridge Psychology Research Ethics Committee (PRE.2020.104) deemed that secondary analysis of deidentified data did not require ethical oversight. Consent for publication: Not applicable. Competing interests: RAIB, MVL, and M-CL are Associate Editors, and EA and BC are Editorial Board members of Molecular Autism. SBC is a former Editor-in-Chief of the journal. ETB reports consultancy work for Boehringer Ingelheim, Sosei Heptares, SR One, and GlaxoSmithKline. ETB, RAIB, JS, and AFA-B are cofounders of Centile Bioscience. PDA receives research support from Biohaven Pharmaceuticals. M-CL has received editorial honorarium from SAGE Publications. RN reported receiving grants from Brain Canada, Hoffman La Roche, Otsuka Pharmaceuticals, and Maplight Therapeutics outside the submitted work. EA reported receiving grants from Roche and Anavex; receiving nonfinancial support from AMO Pharma and CRA-Simons Foundation; and receiving personal fees from Roche, Impel, Ono, and Quadrant outside the submitted work.

Figures

Fig. 1
Fig. 1
Scatter plot showing distribution of individuals across UMAP embeddings (X1 and X2), coloured by subgroup. Each row corresponds to a different set of features: a global, b regional uncorrected, c regional corrected. Scatter plots for the combined dataset are also coloured in by diagnostic
Fig. 2
Fig. 2
Violin plots showing the difference between controls and subgroups for the main global features: total grey matter volume (GMV), mean cortical thickness (CT), total surface area (SA), white matter volume (WMV), subcortical grey matter volume (sGMV), ventricular volume (V). Each row corresponds to a different dataset. a HYDRA, b UMAP and K-medoids
Fig. 3
Fig. 3
Autism regional features results. a Differences in regional features between controls and autism subgroups, both uncorrected and corrected for global effects. The brain plots show Cohen’s d effect size, where red represents a positive effect size (subgroup > control), and blue a negative effect size (subgroup < control). Significant regions are outlined in black. b Alluvial showing flow of participants across techniques for the uncorrected and corrected cases. The colour indicates the subgroups identified by HYDRA
Fig. 4
Fig. 4
ADHD regional features results. a Differences in regional features between controls and ADHD subgroups, both uncorrected and corrected for global effects. The brain plots show Cohen’s d effect size, where red represents a positive effect size (subgroup > control), and blue a negative effect size (subgroup < control). Significant regions are outlined in black. b Alluvial showing flow of participants across techniques for the uncorrected and corrected cases. The colour indicates the subgroups identified by HYDRA
Fig. 5
Fig. 5
Combined dataset regional features results. a Differences in regional features between controls and Autism and ADHD Subgroups, both uncorrected and corrected for global effects. The brain plots show Cohen’s d effect size, where red represents a positive effect size (subgroup > control), and blue a negative effect size (subgroup < control). Significant regions are outlined in black. b Alluvial showing flow of participants across techniques for the uncorrected and corrected cases. The colour indicates the subgroups identified by HYDRA

References

    1. Lenroot RK, Yeung PK. Heterogeneity within autism spectrum disorders: what have we learned from neuroimaging studies? Front Hum Neurosci. 2013;7:733. - PMC - PubMed
    1. Karalunas SL, Nigg JT. Heterogeneity and subtyping in attention-deficit/hyperactivity disorder—considerations for emerging research using person-centered computational approaches. Biol Psychiatry. 2020;88:103–10. - PMC - PubMed
    1. Lombardo MV, Lai MC, Baron-Cohen S. Big data approaches to decomposing heterogeneity across the autism spectrum. Mol Psychiatry. 2019;24:1435–50. - PMC - PubMed
    1. Lai MC, Lombardo MV, Chakrabarti B, Baron-Cohen S. Subgrouping the Autism “Spectrum": Reflections on DSM-5. PLoS Biol. 2013;11: e1001544. - PMC - PubMed
    1. Courchesne E. Brain development in autism: Early overgrowth followed by premature arrest of growth. Ment Retard Dev Disabil Res Rev. 2004;10:106–11. - PubMed

MeSH terms

LinkOut - more resources