Qualitative effects of directed forgetting on memory

Participants studied to-be-remembered (TBR) and to-be-forgotten (TBF) words and received a memory test on all the words. For each recollected word, participants also indicated whether they had a remember or a know type memory. TBF words were recollected less often than TBR words. Moreover, there were fewer remembered memories of TBF words than of TBR words whereas the number of known memories was the same for both types of words. This was so regardless of whether the wards had been studied at a shallow (Experiment I) or a deep (Experiment 2) level. In Experiment 3, participants made both WK and sure/not sure judgments. An interaction emerged between word type and memory type but not between word type and confidence level. Thus, we showed that the attempt to forget has a qualitative effect on memory which cannot be entirely reduced to a change in confidence.