How emotional memory affects face remembering: an ERP investigation

It is known that the longer an information has been memorized, the stronger is its memory trace. At the same time it is known that the emotionally-valenced information has a stronger memory trace than neutral one. Interactive effects between these factors are largely unknown. In this study electrical neuroimaging signals were recorded in healthy controls to explore the neural mechanism of memory for faces of different emotional valence, sex, learning context and temporal recency. In a study phase participants familiarized with the fictional police dossier of 10 victims of dramatic deaths including homicide or earthquake (depicted as attractive and nice persons of about 45 years), twice a day for seven days before EEG recordings. Hundreds of famous movie stars (overlearned), victims (recent) and new faces were presented in an old/new recognition task. ERP responses showed a modulation of anterior N2 and FN400 as a function of face familiarity (with no differences between overlearned and recent faces), while parietal late positivity was sensitive to engram temporal recency (it was much larger to overlearned than recent faces, paralleling behavioral data). However, LP amplitude did not differ to overlearned vs. recent same-sex faces, showing how emotional memory can enhance faces remembering. A late frontal negativity revealed sensitive to source memory.