Brain Functional Connectivity Dynamics in Autism in the Context of Restrictive, Repetitive and Stereotyped Behaviors

摘要

We investigate potential underlying differences in the functional connectivity (FC) profiles of individuals with autism spectrum disorder (ASD) who have severe issues with restrictive, repetitive and stereotypical patterns of behaviour (RRBs), those who have only mild issues, and controls. The focus is on the time-frequency dynamics of FCs that exhibit significant inter-group differences in strength. We introduce a novel measure of coherence volatility, and one of randomness based on 2D entropy over the time-frequency plane. These, together with a raw coherence measure, are computed over distinct frequency bands in wavelet-transform coherence maps. The raw coherence measure inversely correlates with severity of RRBs for multiple FCs which involve the frontal lobe. Volatility positively correlates with RRB severity for a number of FCs, suggesting more frequent attention shifts in ASD, but negatively in one case. Raw coherence suggests ASD groups with severe and mild RRBs share characteristics that distinguish them from controls, while the analyses of volatility, entropy, and phase support the notion of distinct profiles for severe and mild RRBs. Overall findings support the concept of broad heterogeneity in ASD.