Comparing older and younger adults in an event-based prospective memory paradigm containing an output monitoring component

Two experiments with younger and older adults were conducted to investigate the output-monitoring component of event-based prospective memory. In the standard form of the task, participants must remember to press a key when a certain class of items is encountered. To evaluate output monitoring, event-based cues were repeated and participants were asked to press a different key if they could remember that an earlier response was made to a particular cue. Younger adults forgot fewer of their successful responses, but displayed a distinct bias to claim that they had responded earlier when actually they had forgotten to respond. By contrast, older adults displayed this bias much less frequently. Elaborated responding to cues had the effect of improving the performance of younger, but not older adults. The results are discussed in terms of natural repetitions and omission errors that might be made in everyday prospective memory tasks.