(FEF), and the middle frontal gyrus (Supplementary Table 2). The core network mainly included the anterior cingulate, the bilateral insular and dorso-lateral prefrontal cortices. The visual network included the retinotopic occipital cortex and temporal–occipital regions dedicated to visual processing. The sensory-motor network included the precentral, postcentral, and medial frontal gyri, the primary sensory-motor cortices, and the supplementary motor area. Among these five brain networks, only the ventral and the dorsal attention networks were found to be significantly correlated with the P300 reference time-course (Table 1). Analysis of the time-averaged network response (fMRI activation) to the presentation of targets showed that only the ventral attention network consistently responded to the rare stimuli, whereas the averaging procedure seemed to attenuate the signals of the dorsal attention network (Fig. 4). In addition, event-related responses were observed for the visual network and the core network, with larger intensity and shorter duration for the former one, whereas the activity of the sensory-motor network did not seem to be time-locked to the stimulus presentation.
