Fig. 2.

Generation of fMRI networks of interest. (A) Executive Network. The brain areas shown in green are composed of voxels that were significantly active (familiar minus unfamiliar) for any group at each time point (see Online Resources 3 for generation of executive network map). This executive network supports the executive processes required to perform the Verbal Working Memory Task. Mean and spatial variance measures were calculated across this network for all reported analyses. The executive network covers parts of bilateral inferior and middle frontal gyri, anterior cingulate cortex, and bilateral intraparietal sulcus. (B) Default Mode Network. This network is known to be more active during periods of rest than during externally-directed tasks. Suppression of this network is often required to successfully perform cognitively-challenging tasks with greater suppression required for more demanding task conditions. The brain regions shown in purple represent the default mode network across all groups at all timepoints (defined as unfamiliar minus familiar) and cover parts of posterior cingulate/precuneus and superior frontal gyrus. (D) Null Network. The brain regions shown in purple are all of the fMRI voxels that were not included in the executive network coverage (A) but were included in functional slice coverage