A two-process model of strategic monitoring in event-based prospective memory: Activation/retrieval mode and checking

Theorists have suggested that individuals may remember to execute event-based intended actions by deploying executive or attentional resources to monitor for the markers or target events that indicate that it is appropriate to execute the intended actions (e.g., McDaniel Einstein, 2000; Shallice & Burgess, 199 1), but these strategic monitoring views are not specific about the processes that strategic monitoring entails. A more specific idea is outlined here (see also Guynn, 2001) and an experiment with results consistent with this view is reported. According to this two-process view, strategic monitoring entails maintaining the cognitive system in a prospective memory retrieval mode, which may be mediated by increased activation of the prospective memory representation, plus checking whether the circumstances to execute the intended action are present. In the current experiment, concurrent task impairment on nontarget trials, on which participants were instructed to press a key if they saw a target event (i.e., experimental trials), relative to trials on which participants were not instructed to press a key if they saw a target event (i.e., control trials), provided a footprint of strategic monitoring. An interaction of trial type and whether the experimental and control trials alternated or were blocked revealed greater impairment on experimental trials relative to control trials when the trials were blocked than when the trials alternated. Performance on experimental trials did not vary whether the trials alternated or were blocked, while performance on control trials was significantly worse when the trials alternated than when the trials were blocked. The results are consistent with the two-process view and the idea that participants maintained a retrieval mode/activation and checked on experimental trials, neither maintained a retrieval mode/activation nor checked on blocked control trials, and maintained a retrieval mode/activation but did not check on alternating control trials.