EVENT-RELATED POTENTIAL CORRELATES OF IMPLICIT PRIMING AND EXPLICIT MEMORY TASKS

The difference between implicit and explicit memory was examined using event-related potentials (ERP). 16 college students read a study list of 100 words (50 high-emotion and 50 low-emotion) from a video monito r. They then performed a perceptual identification (P.I.) task in whic h they attempted to identify each of a series of 100 words (including 50 from the study list) presented at recognition threshold. Finally, t he subjects performed a yes-no recognition task in which they were pre sented with the other 50 words from the first list and 50 new words (s uprathreshold), and they had to identify which ones had been seen in t he study list. Subjects were more likely to identify studied than nons tudied words in the perceptual identification task; there was no effec t of emotion. In the yes-no recognition task, more high than low-emoti on words were responded to correctly for the old words, whereas more l ow than high-emotion words were responded to correctly for the new wor ds. Data from 11 of the subjects contained enough artifact-free trials for ERP analysis. Analysis revealed that in both the perceptual ident ification task and the yes-no recognition task, P3 amplitude was large r for old than new words, and emotionality had no effect. Analysis of ERPs in the perceptual identification task averaged according to behav ioral response, as well as according to prior study effect showed that P3 amplitude was larger for the studied words than non-studied words, regardless of behavioral response. This effect is electrophysiologica l evidence that a specific event occurs in the brain in response to th e presentation of studied words, whether or not those words are consci ously perceived. P3 latency differed as a function of previous study i n the yes-no task but not the perceptual identification task.