Fig. 3.

Older age is associated with greater functional network segregation and network balance across adolescence. A-B) Age is positively associated with the principal components of network segregation (Panel A) and network balance (Panel B). Principal components are residualized against neighborhood poverty, sex, race, head motion, scan type, mean functional connectivity, family income, and parental education. C-D) Individual graphs from the youngest (8.75 y; Panel C) and oldest (19.75 y; Panel D) participant in the sample. These graphs provide a qualitative illustration of the association between age and network segregation across the sample. Each color represents a brain network, each colored line represents a within-network connection, and each gray line represents a between-network connection. For visualization purposes, only connections stronger than .30 are depicted (isolate nodes at the top right corner represent nodes without connections stronger than .30). Nodes with stronger connectivity are closer together. Overall, functional networks are more segregated (i.e., distance is shorter among nodes within networks and greater among nodes between networks) in older (Panel D) compared to younger (Panel C) youth. Spring graphs generated in Cytoscape (Shannon et al., 2003).