Revisiting the Role of Rehearsal in Intentional Forgetting: A Test of the Selective Rehearsal Account

In the item-method directed forgetting (DF) paradigm, participants study one item at a time, each followed by an instruction to remember (R) or to forget (F) that item. Previous studies have suggested that intentional forgetting occurs by terminating further rehearsal of F items, thus reducing their encoding into the long-term store. We tested the prediction that preventing rehearsal using another resource-demanding task should mimic the DF effect. In Experiments 1a and 1b, we compared a typical DF condition to a condition in which participants performed an alphanumeric equation distraction task to prevent rehearsal. Experiment 1a revealed that an intent to forget reduced memory more than did interfering with rehearsal using this distractor task. In Experiment 1b, we equated rehearsal strategies between conditions and found that preventing rehearsal by an F cue or by a distractor task produced equivalent results. In Experiment 2, implementing a distractor task during R cue presentation reduced memory but did not do so during F cue presentation. We suggest that two critical mechanisms are at play during encoding in intentional forgetting: the selective enhancement of R items by rehearsal and the selective removal of F items.