Functional magnetic resonance imaging study of children's brain development in phonological processing and speeded naming

The brain structure and language skills of children are understood to be in a phase of rapid development and are especially represented by key phonological-semantic expressions that actively develop with age. In the present study, resting-state functional magnetic resonance imaging data from 85 healthy children were retrospectively analyzed. Correlations of the phonological processing and speeded naming of specific brain regions of interest with age were assessed using the fractional amplitude of low-frequency fluctuations (fALFF), degree centrality (DC), regional homogeneity (ReHo), and chain mediation effect analysis. Our results suggest that the developmental stages of children's posterior cingulate gyrus (PCC) and right inferior frontal gyrus (IFG) mediate language development in children. Additionally, the functional similarity of the bilateral IFG triangular part was noted during development as was the stronger activation and higher local and whole-brain connectivity of the left IFG triangular part. Moreover, the PCC displayed stronger activation and higher local connectivity in the same period. Our data suggest that the development of the PCC and right IFG and the similarity of bilateral IFG function are important imaging markers of phonological processing and speeded naming in children and that the PCC and IFG show a more comprehensive development with age.