Developmental differences of large-scale functional brain networks for spoken word processing

A dual-stream dissociation for separate phonological and semantic processing has been implicated in adults' language processing, but it is unclear how this dissociation emerges with development. By employing a graph-theory based brain network analysis, we compared functional interaction architecture during a rhyming and meaning judgment task of children (aged 8-12) with adults (aged 19-26). We found adults had stronger func-tional connectivity strength than children between bilateral inferior frontal gyri and left inferior parietal lobule in the rhyming task, between middle frontal gyrus and angular gyrus, and within occipital areas in the meaning task. Meanwhile, adults but not children manifested between-task differences in these properties. In contrast, children had stronger functional connectivity strength or nodal degree in Heschl's gyrus, superior temporal gyrus, and subcortical areas. Our findings indicated spoken word processing development is characterized by increased functional specialization, relying on the dorsal and ventral pathways for phonological and semantic processing respectively.

Automated summary

Our study compared functional connectivity in language processing between children and adults using brain network analysis. We found that adults showed stronger connectivity between bilateral inferior frontal gyri and left inferior parietal lobule in the rhyming task, and between middle frontal gyrus and angular gyrus, as well as within occipital areas in the meaning task. Children, on the other hand, showed stronger connectivity in Heschl's gyrus, superior temporal gyrus, and subcortical areas. These findings suggest that the development of spoken word processing is characterized by increased functional specialization, with phonological and semantic processing relying on dorsal and ventral pathways, respectively.