Maturation Trajectories of Cortical Resting-State Networks Depend on the Mediating Frequency Band
This research addresses the neural mechanisms of cortical maturation, relevant for understanding typical and atypical development, but is incremental as it builds on known network reorganization.
The study investigated how different cortical frequency bands mediate the maturation of resting-state networks from childhood to adulthood, finding that gamma band networks follow an asymptotic trajectory with increased integration, while beta band networks follow a linear trajectory with increased segregation, with minimal spatial overlap in hubs.
The functional significance of resting state networks and their abnormal manifestations in psychiatric disorders are firmly established, as is the importance of the cortical rhythms in mediating these networks. Resting state networks are known to undergo substantial reorganization from childhood to adulthood, but whether distinct cortical rhythms, which are generated by separable neural mechanisms and are often manifested abnormally in psychiatric conditions, mediate maturation differentially, remains unknown. Using magnetoencephalography (MEG) to map frequency band specific maturation of resting state networks from age 7 to 29 in 162 participants (31 independent), we found significant changes with age in networks mediated by the beta (13-30Hz) and gamma (31-80Hz) bands. More specifically, gamma band mediated networks followed an expected asymptotic trajectory, but beta band mediated networks followed a linear trajectory. Network integration increased with age in gamma band mediated networks, while local segregation increased with age in beta band mediated networks. Spatially, the hubs that changed in importance with age in the beta band mediated networks had relatively little overlap with those that showed the greatest changes in the gamma band mediated networks. These findings are relevant for our understanding of the neural mechanisms of cortical maturation, in both typical and atypical development.