How does cue predictability influence prospective memory? An fMRI study.

The study was aimed at investigating the neural correlates of cue predictability in prospective memory. To this end, two functional magnetic resonance (fMRI) experiments were performed, either in an event-based and in a time-based context. The results revealed that in the event-based task strategic monitoring was principally involved in predictable blocks, where the cue was not expected, and it was associated with a deactivation of the rostral prefrontal cortex. On the other hand, the superior parietal lobe was maximally active in blocks where the cue was expected. In the time-based task, the activation in the blocks where the cue was not expected was higher in the anterior cingulated cortex and superior frontal gyrus, while the caudate nucleus was active during the block requiring the monitoring of time, therefore likely reflected time processing processes. These results suggest that PM cue predictability influences monitoring processes and that neural correlates of strategic monitoring, but not maintaining processes, were task-specific.