background In explicit memory tasks an emotional enhancement effect has frequently be found for various stimuli, like words, pictures and faces. Less is known about emotional effects in implicit memory, where task performance is facilitated without conscious awareness of prior learning experiences. Some kinds of implicit memory tasks also seem to be affected by emotional content. However, it remains unclear whether processing enhancement of emotional words also occurs in perceptually driven implicit tasks, as it has been found for explicit memory tasks.
aim We compared perceptual implicit priming and explicit recognition memory for emotional and neutral words within one study. 
methods Fifty-one healthy women studied 240 visually and auditorily presented words under deep and shallow encoding instructions during day 1. After a 24h-interval perceptual implicit memory was tested visually with a word-fragment- completion (wfc) task, followed by an explicit visual recognition task.
results In both tasks, emotional positive and negative words were preferentially processed compared to neutral words; more emotional words were filled in into the word fragments and were recognized explicitly. Priming but not recognition suffered from cross-modality manipulation, while recognition but not priming was facilitated by deep encoding.
conclusions Even a perceptual implicit task, which does not require semantic, conceptual processing, is not immune against the facilitating effects of emotional content. Both the explicit and the perceptual implicit memory task show better performance for emotional words compared to neutral ones. Moreover, this enpresentaties was biased towards positive words for implicit memory and towards negative words for explicit memory suggesting a valence-specific dissociation of emotional enhancement effects in implicit and explicit forms of memory. Further, the findings support a dissociation between explicit and implicit memory with respect to levels-ofprocessing and cross-modality manipulations.