My dissertation project tested current theories of the picture superiority effect (better memory for pictures than words). A popular theory is dual coding (Paivio, 1991), which states that pictures are better remembered because they are encoded with two specific codes (pictorial and verbal) while words elicit just a single code (verbal). The extra code associated with pictures give them an advantage during retrieval. A more recent theory (transfer appropriate processing) discussed by Weldon and Roediger (1987) also claims that pictures and words elicit different types of information at encoding, but further states that the type of processing engaged by the retrieval task is also important. According to the theory, if the retrieval task requires conceptual processing, any items that are encoded with more conceptual processing will be more likely retrieved than items encoded with little or no conceptual processing. It is believed that pictures are encoded with more conceptual processing and this is why they are better recalled on conceptual memory tests. For tasks that require perceptual processing (e.g., traditional implicit memory tasks) a match in the type of percept encoded during study will be important. If words are used as cues on perceptual tests, studied words will be better recalled. If pictures are the cues on the perceptual test, studied pictures will be better recalled. Weldon and Roediger (1987) presented data which supported these predictions of the theory.