Retrieval-induced forgetting in implicit memory tests: The role of test awareness

Abstract

A number of studies using the retrieval-practice paradigm have shown that inhibition can play a role in retrieval from memory (for a review, see Anderson, 2003). In the retrieval-practice paradigm, participants first study a number of category-exemplar pairs, followed by retrieval practice with half of the studied exemplars from half of the studied categories. Retrieval practice is carried out using a category-plus-word-stem cued recall task. Their memory is then tested for both practiced and unpracticed exemplars. Typically, results show an increase in recall for practiced items (RPϩ items) and a decrease in recall for unpracticed items (RPϪ items) that belong to the same category as the practiced items, when compared with exemplars from categories that received no retrieval practice (NRP items). In this final recall test, the names of the studied categories are used as cues.Anderson and Spellman (1995) adapted the retrievalpractice paradigm and found retrieval-induced forgetting using independent extralist retrieval cues. These results led Anderson and Spellman to conclude that retrievalinduced forgetting is an inhibitory effect and that the relation between the category and the exemplar or between the practiced and unpracticed items within the category is not inhibited, but rather the unpracticed item itself. They considered cue-independent forgetting to be an empirical criterion for inhibition.However, if retrieval-induced forgetting is due to item inhibition, it should also be found using different types of tests. In principle, the retrieval-induced forgetting effect should be found with any type of test assessing the activation of the inhibited item. A number of studies have investigated the validity of this claim using implicit memory tasks rather than the category-cued recall task used traditionally in the test phase of the retrieval-practice paradigm. Unlike what is done in explicit memory tasks such as category-cued recall, no reference is made to the study phase in implicit memory tasks.Butler, Williams, Zacks, and Maki (2001) used a wordfragment completion task to test implicit memory in the retrieval-practice paradigm. They did not obtain retrievalinduced forgetting. Nor did they obtain retrieval-induced forgetting in several experiments with explicit tests of memory such as word-fragment-cued recall, categoryplus-word-fragment-cued recall, and category-plus-stemcued recall. They found retrieval-induced forgetting only in the standard category-cued recall condition. Therefore, retrieval-induced forgetting seems to depend more on visually presenting a part of the target item than on whether the final memory test is implicit or explicit. In addition, Butler et al. note that most participants detected the connection between the test phase and the study and practice phases. Therefore, the word-fragment completion task could not be regarded as truly implicit.Perfect, Moulin, Conway, and Perry (2002) used five different tests of implicit memory in the retrieval-practice paradigm: category generation, cate...

Effects of retrieval practice on conceptual explicit and implicit consumer memory

“…Finally, during the test phase, Cadburys is cued from a different product category such as 'Chocolate'. In tests of implicit memory, the independent probe technique has been used recently by Camp, Pecher, and Schmidt (2005). They found that retrieval-induced forgetting was present only for participants who were aware of the relationship between the study and test phases.…”

“…However, research that has made use of such measures indicates that many participants do become aware spontaneously of the study-test relationship even if not informed by the experimenter (e.g. Bowers & Schacter, 1990;Camp et al, 2005;Mulligan et al, 1999). The issue at stake here relates to the distinction between retrieval intention and awareness (Richardson-Klavehn & Gardiner, 1995;Richardson-Klavhen et al, 1996).…”

“…Awareness refers to the extent to which the participant is conscious of the fact that some test items appeared as study items. In the Camp et al (2005) study, participants were classified as test aware if they indicated knowledge of the overlap between the study and test phase and, crucially, continued to use incidental (implicit) retrieval strategies as indicated by responses on the post-test questionnaire. Thus these findings do not contradict the findings of Experiment 2 as in this experiment participants were aware and made use of the assigned retrieval strategies, again as indicted by responses on the post-test questionnaire.…”

Reassessing critiques of the independent probe method for studying inhibition.

“…A broad base of findings supports cue independence under many conditions in both episodic and semantic memory (e.g., M. C. Anderson & Bell, 2001; M. C. Anderson, Green, & McCulloch, 2000;M. C. Anderson & Spellman, 1995;Aslan, Bäuml, & Grundgeiger, 2007;Camp, Pecher, & Schmidt, 2005;Levy, McVeigh, Marful, & Anderson, 2007;MacLeod & Saunders, 2005;Saunders & MacLeod, 2006;Shivde & Anderson, 2001; for exceptions, see Camp, Pecher, & Schmidt, 2007;Perfect et al, 2004;Williams & Zacks, 2001). Thus, retrieval often appears to induce RIF that reflects changes to the state of the competitor, consistent with inhibition.…”

“…The nature of this influence, at present, is unclear. On the one hand, Perfect et al (2004) and Camp et al (2005) argued that covertly recalling the practiced category may trigger recall of practiced items (e.g., Orange) that would then block unpracticed items (e.g., Banana). If so, blocking could explain independent probe impairment, albeit with complex assumptions about the cues participants use.…”