Our finding is in agreement with a number of recent fMRI and combined EEG-fMRI studies that suggest that the DMN plays an active role in task-related processing. Spontaneous DMN fluctuations have been shown to affect visual task performance (Eichele et al., 2008) and during rest have inversely correlated with the frontal theta rhythm (Scheeringa et al., 2008), which is typically associated with cognitive processing. There is also evidence of transient event-related suppression of DMN regions related to increased cognitive load during a visual N-back task (Esposito et al., 2006; 2009a) and during motion discrimination (Singh and Fawcett, 2008) and auditory oddball tasks (Eichele et al., 2005), though in the latter case corresponding to an earlier component. This converging evidence supports the idea that DMN regions modulate selective attention for optimal allocation of attentional resources.
