Default mode network scaffolds immature frontoparietal network in cognitive development
Cerebral Cortex November 1, 2022 Menglu Chen, Ying He, Lei Hao et al.
The default mode network (DMN) and the frontal parietal network (FPN) mature at different rates in children, with the DMN reaching adult-like levels earlier than the FPN. In a longitudinal developmental fMRI study using an n-back task with 528 children and 103 young adults, children showed greater improvement over time but still performed worse than adults. Children had weaker DMN deactivation and FPN activation but stronger coupling between DMN and FPN regions. The coupling between the posterior cingulate cortex and dorsolateral prefrontal cortex mediated the relationship between age and working memory-related functional coupling, and together with task-invoked PCC activity, accounted for children's behavioral improvement. The DMN appears to provide a scaffolding effect supporting the immature FPN during executive function development.