Connectional axis of individual functional variability: Patterns, structural correlates, and relevance for...

Area of Science:

• Neuroscience
• Cognitive Science
• Human Brain Imaging

Background:

• The human cerebral cortex displays complex functional synchronization across regions, but individual differences in functional connections are significant.
• The spatial organization and developmental relevance of functional connectivity (FC) variability across the brain's connectome remain poorly understood.

Purpose of the Study:

• To identify and characterize the spatial organization of functional connectivity variability across the human connectome.
• To investigate the relationship between functional connectivity variability, structural connectivity, cognitive development, and higher-order cognition.

Main Methods:

• Analysis of macroscale functional synchronization and individual variability in functional connections across the human connectome.
• Identification of a connectional axis based on edge-level FC variability.
• Examination of the association between this axis, structural connectivity variability, developmental changes in youth, and cognitive performance.

Main Results:

• A distinct connectional axis of FC variability was identified, decreasing from within-network to between-network connections and from association to sensorimotor networks.
• This axis correlates with the spatial pattern of structural connectivity variability and shows developmental refinement in youth, indicated by an increasing flatter slope.
• The slope of the connectional variability axis is positively associated with performance in higher-order cognitive tasks.

Conclusions:

• A novel connectional axis of functional variability, linked to structural connectome variability, has been revealed in the human brain.
• This axis undergoes refinement during development and is functionally relevant, showing a positive relationship with higher-order cognitive abilities.