We found a significant main effect of task on both region- and edge-wise connectivity in a distributed network of regions incorporating primarily frontal and temporal cortices. These findings are consistent with activation-based studies showing greater prefrontal activation for B relative to A cue trials (27,29,67). In addition, we found strong task effects on connectivity of medial temporal regions, areas that have not been identified as key task-related regions in prior work. This likely reflects the differing sensitivities of beta series connectivity- and activation-based methods. The former are sensitive to task effects on interregional correlations in trial-to-trial variations of task-evoked responses, whereas the latter characterize mean differences in the strength of these responses. Consequently, the two do not always yield convergent findings (28) (Section S1 in Supplement 1).
