The neural substrates associated with attentional resources and difficulty of concurrent processing of the two verbal tasks

► We clarified the mechanism of divided attention during complex story comprehension. ► Fronto-parietal activations and temporal-fusiform deactivations were observed. ► Increase in synchronization between frontal and parietal regions was observed. ► Fronto-parietal and temporal-fusiform regions play crucial roles in the dual task.