The effect of pre-existing memory representations on repetitionrelated N250r and N400

Studies of repetition priming have found two face-sensitive event-related potential(ERP) components:the N250 r showing positive deflection at frontal region and negative deflection at temporal region, and the N400 showing positive deflection at frontal and centro-parietal regions, both of which depend in part upon the presence or absence of a pre-existing face representation. However, the N250 r is rarely reported for a repetition interval between immediate repetition and 3 min; in addition, whether different types of representations function in the same way is also of interest. The goal of the present experiment is to compare the ERP patterns for faces versus letter strings as a function of the pre-existing memory representation with a repetition interval of 1.5 min on average. We found reliable frontally positive N250 r and N400 for famous faces and words; marginally significant effects for pseudo-words;and only the centro-parietal N400 for unfamiliar faces.Collectively, the N250 r persists in the present intermediate intervals, and both the frontal N250 r and the frontal N400 are domain-general, sensitive to the pre-existing memory representation.