Effects of hearing words, imaging hearing words, and reading on auditory implicit and explicit memory tests

In four experiments, we examined the degree to which imaging written words as spoken by a familiar talker differs from direct perception (hearing words spoken by that talker) and reading words (without imagery) on implicit and explicit tests. Subjects first performed a surface encoding task on spoken, imagined as spoken, or visually presented words, and then were given either an implicit test (perceptual identification or stem completion) or an explicit test (recognition or cued recall) involving auditorily presented words. Auditory presentation at study produced larger priming effects than did imaging or reading. Imaging and reading yielded priming effects of similar magnitude, whereas imaging produced lower performance than reading on the explicit test of cued recall. Voice changes between study and test weakened priming on the implicit tests, but did not affect performance on the explicit tests. Imagined voice changes affected priming only in the implicit task of stem completion. These findings show that the sensitivity of a memory test to perceptual information, either directly perceived or imagined, is an important dimension for dissociating incidental (implicit) and intentional (explicit) retrieval processes.