Retrieval memory is supported by distinct retrieval process known as recollection and familiarity. These two process have been associated with distinct event related potentials (ERPs). At the time of retrieval, familiarity is associated with modulation of the FN400, an enhanced positivity for old items relative to new items observed from approximately 400-600ms post stimulus onset. The FN400 tends to have mid-frontal scalp distribution which can extend to left and right frontal areas and central midline regions. In contrast, recollection has been linked with modulation of positive going waveform that emerges approximately 600ms post stimulus and is typically maximal over parietal sites and referred to as late positive component (LPC). In addition, FN400 is found to increase gradually as a function of item retrieval confidence whereas LPC is limited to high confidence retrieval response.