Time-varying Functional Connectivity Predicts Fluctuations in Sustained Attention in a Serial Tapping Task
The mechanisms for how large-scale brain networks contribute to sustained attention is unknown. Attention fluctuates from moment to moment and this continuous change is consistent with dynamic changes in functional connectivity between brain networks involved in the internal and external allocation of attention. In this study, we investigated how brain network activity varied across different levels of attentional focus (i.e., "zones"). Participants performed a finger-tapping task, and guided by previous research, in-the-zone performance or state was identified by low reaction time variability and out-of-the-zone as the inverse. Employing a novel method of time-varying functional connectivity, called the quasi-periodic pattern analysis (i.e., reliable network-level low-frequency fluctuations), we found that the activity between the default mode network (DMN) and task positive network is significantly more anti-correlated during in-the-zone states versus out-of-the-zone states. Furthermore, it is the fronto-parietal control network (FPCN) that drives this difference. Activity in the dorsal attention network (DAN) and DMN were desynchronized across both zone states. During in-the-zone periods, FPCN synchronized with DAN, while during out-of-the-zone periods, FPCN synchronized with DMN. In contrast, the ventral attention network synchronized more closely with DMN during in-the-zone periods compared to out-of-the-zone periods. These findings demonstrate that time-varying functional connectivity across different brain networks varies with fluctuations in sustained attention.