The Effect of Forgetting Strategies on Memory Performance: Behavioral and Electroencephalography Evidence

Background/Objectives: This study aimed to examine the effect of different forgetting strategies on intentional forgetting, specifically comparing the passive decay strategy ('forgetting by keeping the mind blank') and the active rehearsal strategy ('forgetting by rehearsing other words'). Methods: An item-method directed forgetting paradigm was used in a between-subjects design while the electroencephalogram (EEG) was recorded. Results: Behavioral results showed that both strategies produced a robust directed forgetting (DF) effect, but participants in the active rehearsal group recognized more to-be-remembered (TBR) words. Event-related potential (ERP) results indicated that both groups exhibited a DF effect in the cue-induced P2-P3 complex. Compared to the passive decay group, the active rehearsal group did not show a DF effect in the cue-induced later positive component (LPC); instead, a significant DF effect appeared in the P600 during the test phase. Time-frequency results showed that the passive decay group exhibited a significant DF effect in the 9-25 Hz frequency band during the late stage of cue processing, while the active rehearsal group showed a reversed DF effect in the 8-16 Hz frequency band during the mid-stage of cue processing. Conclusions: These findings indicate that forgetting strategies do not affect the recognition performance of to-be-forgotten (TBF) words. The active rehearsal strategy led participants to shift attention from TBF to TBR words, resulting in better TBR recognition performance in this group.