Connectivity in ALS II (CoALS II): a study of structural and functional connectivity in ALS

Area of Science:

• Neuroscience
• Neurodegenerative Diseases
• Systems Biology

Background:

• Amyotrophic lateral sclerosis (ALS) is increasingly viewed as a network-level neurodegenerative disease.
• Previous research often studied white matter integrity or functional connectivity separately.
• The interplay between structure and function and its changes in ALS are not well understood.

Purpose of the Study:

• To investigate structure-function coupling in amyotrophic lateral sclerosis (ALS) using a multimodal approach.
• To understand how structural and functional brain networks are reorganized in ALS.
• To explore the relationship between white matter integrity and functional connectivity in ALS.

Main Methods:

• Multimodal connectomic analysis integrating cortical thickness, diffusion MRI, and functional MRI (resting-state and task-based).
• Graph-theoretical network analysis and ROI-wise correlation for structure-function correspondence.
• Utilized a 104-node parcellation based on the Desikan-Killiany atlas.

Main Results:

• ALS participants maintained global network topology but showed selective reorganization in motor and interhemispheric pathways.
• Cortical covariance networks had minimal association with functional dynamics.
• White matter connectivity derived from diffusion MRI remained aligned with functional organization, even enhancing during tasks.

Conclusions:

• Structure-function coupling in ALS is reorganized, not globally diminished.
• Robust white matter-function relationships persist alongside weaker cortical-function associations.
• Findings refine the disconnection model and emphasize multimodal metrics for ALS research and biomarker development.