br Materials and methods br Results br
Materials and methods
Discussion In the present study, we investigated neural response patterns of all four central subcomponents of reading, i.e. prelexical, orthographic, phonological, and lexico-semantic processing in a large sample of normally developing German-speaking children aged nine to 13 years. We systematically examined how the core regions of the widespread reading system of children (cf. Martin et al., 2015) c-myc inhibitor linked to each of the component processes and observed both significant overlap as well as partly distinct neural response patterns. In particular, prelexical processing was not entirely confined to the posterior vOT but was associated with additional activity in the SPL and even the frontal system (PRG). Consistent with our predictions, orthographic processing was associated with neural activity in the vOT, including the FG and ITG, accompanied by activity in the IFG. Notably, phonological processing was the only component process eliciting activity in all four core regions of the child reading system. Compared to orthographic processing, we observed additional activity in the MTG and PPC as well as more distributed activity in the IFG. Similar to phonological processing, the MTG was involved in semantic processing. The bilateral SMA showed pronounced involvement in all subcomponent tasks except for prelexical processing.
Conclusion Our attempt to “neurofunctionally dissect” the widespread core reading system of children into its basic subcomponents showed both similarities and differences across the four component processes. The most striking finding is that the vOT was not only in charge of low-level orthographic processing but appeared to be involved in all four components (cf. Schurz et al., 2010). Similarly, the IFG was not only activated by lexico-semantic categorization (Glezer et al., 2016; Montant et al., 2011) and glucose was true when differences in within-scanner performance were taken into account to partial out potential differences in task demands. Thus, the present data support the idea of an interactive network account of visual word processing. Whether those regions addressing all subcomponents of reading (i.e., vOT, IFG) may serve as potential hubs within such an interactive network needs further investigation.
Conflict of interest
Funding This work was supported by the German Federal Ministry of Education and Research (Bundesministerium für Bildung und Forschung, BMBF) with grants FKZ 01GJ1010A and 01GJ1404.