Disrupted small-world brain network in children with Down Syndrome

Abstract

Objective: To explore how the global organization or topology of the functional brain connectivity (FBC) is affected in Down Syndrome (DS).

Methods: As the brain is a highly complex network including numerous nonlinearly interacted neuronal areas, the FBCs of typically developing (TD) children and DS patients were computed using a nonlinear synchronization method. Then the differences in global organization of the obtained FBCs of the two groups were analyzed, in all electroencephalogram (EEG) frequency bands, in the framework of Small-Worldness Network (a network with optimum balance between segregation and integration of information).

Results: The topology of the functional connectivity of DS patients is disrupted in the whole brain in alpha and theta bands, and especially in the left intra-hemispheric brain networks in upper alpha band.

Conclusions: The global organization of the DS brain does not resemble a Small-World network, but it works as a random network.

Significance: It is the first study on global organization of the FBC in DS.

Keywords: Down Syndrome; Electroencephalogram; Functional brain connectivity; Small-Worldness; Visibility Graph Similarity.