Abstract
The purpose of this study was to compare, across the lifespan, different costs that can occur in a prospective memory task. Specifically, we were interested in investigating the costs of responding to both activated (i.e., monitoring costs) and deactivated intentions (i.e., aftereffects). In two experiments, children, younger, and older adults performed an event-based prospective memory task consisting of four blocks (a baseline block, a prospective memory block without the occurrence of prospective memory cues, a prospective memory block with the occurrence of prospective memory cues, and a deactivation block in which unexpected no-more-relevant prospective memory cues occurred). The results revealed that monitoring costs and aftereffects were present in all age groups. Although children engaged in monitoring, their prospective memory performance was lower than for young and older adults.
Moreover, aftereffects of responding to deactivated intentions were more pronounced in children and older adults. In Experiment 2, we were interested in examining whether these costs would be modulated by the type of prospective memory cues (semantic vs. perceptual). In fact, aftereffects were modulated by cue type with semantic cues producing higher costs than perceptual cues. These outcomes shed light on the different sources and the extent of cognitive costs resulting from responding to activated and deactivated intentions across the lifespan.