Dataset Information

Towards robust and replicable sex differences in the intrinsic brain function of autism.

ABSTRACT:

Background

Marked sex differences in autism prevalence accentuate the need to understand the role of biological sex-related factors in autism. Efforts to unravel sex differences in the brain organization of autism have, however, been challenged by the limited availability of female data.

Methods

We addressed this gap by using a large sample of males and females with autism and neurotypical (NT) control individuals (ABIDE; Autism: 362 males, 82 females; NT: 409 males, 166 females; 7-18 years). Discovery analyses examined main effects of diagnosis, sex and their interaction across five resting-state fMRI (R-fMRI) metrics (voxel-level Z?>?3.1, cluster-level P?ResultsDiscovery analyses in ABIDE revealed significant main effects of diagnosis and sex across the intrinsic functional connectivity of the posterior cingulate cortex, regional homogeneity and voxel-mirrored homotopic connectivity (VMHC) in several cortical regions, largely converging in the default network midline. Sex-by-diagnosis interactions were confined to the dorsolateral occipital cortex, with reduced VMHC in females with autism. All findings were robust to different pre-processing steps. Replicability in independent samples varied by R-fMRI measures and effects with the targeted sex-by-diagnosis interaction being replicated in the larger of the two replication samples-EU-AIMS LEAP.

Limitations

Given the lack of a priori harmonization among the discovery and replication datasets available to date, sample-related variation remained and may have affected replicability.

Conclusions

Atypical cross-hemispheric interactions are neurobiologically relevant to autism. They likely result from the combination of sex-dependent and sex-independent factors with a differential effect across functional cortical networks. Systematic assessments of the factors contributing to replicability are needed and necessitate coordinated large-scale data collection across studies.

SUBMITTER: Floris DL

PROVIDER: S-EPMC7923310 | biostudies-literature | 2021 Mar

REPOSITORIES: biostudies-literature

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Publications

Towards robust and replicable sex differences in the intrinsic brain function of autism.

Floris Dorothea L DL Filho José O A JOA Lai Meng-Chuan MC Giavasis Steve S Oldehinkel Marianne M Mennes Maarten M Charman Tony T Tillmann Julian J Dumas Guillaume G Ecker Christine C Dell'Acqua Flavio F Banaschewski Tobias T Moessnang Carolin C Baron-Cohen Simon S Durston Sarah S Loth Eva E Murphy Declan G M DGM Buitelaar Jan K JK Beckmann Christian F CF Milham Michael P MP Di Martino Adriana A

Molecular autism 20210301 1

<h4>Background</h4>Marked sex differences in autism prevalence accentuate the need to understand the role of biological sex-related factors in autism. Efforts to unravel sex differences in the brain organization of autism have, however, been challenged by the limited availability of female data.<h4>Methods</h4>We addressed this gap by using a large sample of males and females with autism and neurotypical (NT) control individuals (ABIDE; Autism: 362 males, 82 females; NT: 409 males, 166 females; ...[more]

PMID: 33648569

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Dataset Information

Towards robust and replicable sex differences in the intrinsic brain function of autism.

Background

Methods

Limitations

Conclusions

Publications

Towards robust and replicable sex differences in the intrinsic brain function of autism.

Similar Datasets

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