Assessing activation without source monitoring in the DRM false memory paradigm

Four experiments examined whether studying a single Deese/Roediger-McDermott (DRM) list produces semantic priming for nonstudied critical items (CIs) and semantic + repetition priming for studied associates. After 30 s of mental arithmetic that followed the study of a DRM list, priming was assessed in a lexical decision task when the nonwords were either pronounceable (Experiment 1) or pseudohomophones (Experiments 2-4). Priming was measured relative to a baseline containing exactly the same CIs and associates that had not been primed by their related DRM lists. Significant CI semantic priming effects occurred in all four experiments, whether or not there was within-test priming from a related associate preceding the CI by 3-7 items. To our knowledge, these are the first experiments using standard DRM study procedures to provide a convincing demonstration of a genuine CI semantic priming effect in a delayed indirect memory test that should be free of intentional retrieval strategies. Discussion focuses on measuring long-term semantic activation effects without the influence of source monitoring in a lexical decision task.