Linking functional and structural brain organisation with behaviour in autism: a multimodal EU-AIMS Longitudinal...

Area of Science:

• Neuroscience
• Psychiatry
• Medical Imaging

Background:

• Autism spectrum disorder (ASD) research often analyzes brain structure and function separately.
• Integrating multimodal neuroimaging data can enhance sensitivity and reveal novel insights into brain organization in ASD.

Purpose of the Study:

• To identify novel brain-organization phenotypes in autism by integrating structural and functional neuroimaging data.
• To investigate the combined contributions of structural and functional brain properties to autism.

Main Methods:

• Utilized multimodal MRI (T1, diffusion-weighted, resting-state functional), behavioral, and clinical data from the EU AIMS Longitudinal European Autism Project (LEAP).
• Extracted grey matter density, probabilistic tractography connectivity, and connectopic maps, integrating them using Linked Independent Component Analysis.
• Employed linear mixed-effects models to assess group differences and associations with behavioral measures, accounting for covariates and longitudinal data.

Main Results:

• Identified a significant difference between autistic and non-autistic groups in one integrated component (p_adj=0.02).
• This component was primarily driven by the functional organization of the right fusiform gyrus (connectopic map 2).
• While nominal associations with behavioral measures were observed, none survived multiple comparison correction.

Conclusions:

• Functional brain phenotypes, specifically the topographic organization of functional connectivity, are key drivers of associations with autism.
• This multimodal approach reveals autism-specific functional connectivity patterns, expanding upon previous unimodal studies.
• Findings underscore the importance of integrating structural and functional neuroimaging for a comprehensive understanding of autism.