Classifying implicit memory tests: Category association and anagram solution

In three experiments we investigated the nature of two implicit memory tests, free associating to category names and solving anagrams, by manipulating several variables during study. Additional implicit and explicit tests were included for comparison (word fragment completion and free recall). Primed category association responded like free recall by showing an advantage from generating words relative to reading them out of context, a levels of processing effect, and no effect of study modality (visual or auditory). The results of these variables on anagram solution were less clear cut, but tended to resemble the effects of primed word fragment completion (a modality effect, only a slight levels of processing effect, and little priming from pictures). Dissociations were obtained between explicit and implicit tests (e.g., free recall and primed fragment completion), but more importantly between implicit tests (e.g., primed fragment completion and category association). Because implicit tests can be dissociated, no single system underlies their performance; we emphasize instead their processing requirements to explain dissociations among tests.