Effect of the congruity of emotional contexts at encoding on source memory: Evidence from ERPs

Emotion's influence on source memory has proven more elusive and the lack of studies investigates the effect of the congruent emotional contexts on source memory. Here, we investigated these issues using event-related potentials (ERPs) to assess emotional-induced neural correlates. During encoding, congruent word-picture (a word 'shoes' - a picture described shoes) and incongruent word-picture (a word 'pepper' - a picture described shoes) with a prompt (Common? or Natural?) were presented. At retrieval, participants indicated which prompts were concomitantly presented with the word during encoding. Behavioral results revealed that source memory accuracy was enhanced in the neutral contexts compared to the negative contexts, and enhanced in the incongruent condition relative to the congruent condition, suggesting that emotional contexts impaired source memory performance, and incongruent information enhanced source memory. ERPs results showed that early P2 old/new effect (150-250 ms) and FN400 old/new effect (300-450 ms) were observed for words with correct source that had been encoded in the congruent emotional contexts, and that a larger parietal old/new effect, between 500 and 700 ms, was observed for words with correct source that had been encoded in the incongruent condition than in the congruent condition, irrespective the nature of context. The ERPs results indicate that retrieval of source details for the associated emotionally congruent information supports the idea that emotional events could attract more attentional resources, and reflects the contribution of familiarity-based process. Meanwhile, retrieval of source details for the associated incongruent information reflects a stronger contribution of recollection-based process.