Disrupted small-world brain network in children with Down Syndrome

Area of Science:

• Neuroscience
• Network Science
• Developmental Disorders

Background:

• The brain's functional brain connectivity (FBC) forms a complex network critical for cognitive functions.
• Down Syndrome (DS) is associated with altered brain development and function, but its impact on global FBC topology remains underexplored.

Purpose of the Study:

• To investigate the global organization and topology of FBC in individuals with DS compared to typically developing (TD) individuals.
• To analyze differences in FBC network properties across various electroencephalogram (EEG) frequency bands.

Main Methods:

• Computed FBCs for TD children and DS patients using a nonlinear synchronization method.
• Analyzed global network organization using Small-Worldness Network framework, assessing segregation and integration.
• Examined differences across all EEG frequency bands, focusing on alpha and theta bands.

Main Results:

• The functional connectivity topology in DS patients is globally disrupted across alpha and theta EEG bands.
• Significant alterations are particularly pronounced in left intra-hemispheric brain networks within the upper alpha band.
• DS brain networks exhibit deviations from Small-World properties.

Conclusions:

• The global organization of the DS brain's functional connectivity deviates significantly from Small-World network characteristics.
• Instead of an optimized balance, DS brain networks function more like random networks.
• This research provides the first analysis of global FBC organization in Down Syndrome, highlighting topological disruptions.