EVENT-RELATED POTENTIALS OF VERBAL ENCODING INTO EPISODIC MEMORY - DISSOCIATION BETWEEN THE EFFECTS OF SUBSEQUENT MEMORY PERFORMANCE AND DISTINCTIVENESS

Episodic memory encoding and distinctiveness detection were examined u sing event-related potentials (ERP) in a single-trial word list learni ng paradigm with free recall following distraction. To manipulate dist inctiveness, encoding of high- and very low-frequency words was contra sted. Amplitudes of the N400 and late positive component (LPC) were la rger for low- than for high-frequency words, and ERPs were more positi ve for subsequently recalled than not recalled words. This subsequent memory effect was dissociated from the correlates of distinctiveness b y polarity for the N400 and by time course for the LPC and dissociable into two effects. The data suggest that the first subsequent memory e ffect, which occurred for both word categories, is more directly relat ed to episodic memory formation, whereas the second effect, which occu rred for high-frequency words only, is related to processes influencin g episodic encoding success indirectly.