The Inhibitory Effect of Emotional Conflict Control on Memory Retrieval

Abstract

Evidence is mounting that emotional conflict is mainly resolved by the rostral anterior cingulate inhibiting the processing of emotional distractors. However, this theory has not been verified from the perspective of memory retrieval. This experiment aimed to explore the offline effect of emotional conflict processing on memory retrieval. We adopted a modified encoding-retrieval paradigm to explore this issue. Participants' electroencephalography (EEG) signal were also collected. A face-word Stroop task was used to create the congruency factor. In addition, an old/new judgment task was used to evaluate the recognition performance. During the retrieval phase, the response time of the incongruent condition was longer and the recognition accuracy was lower compared with congruent and neutral conditions in the behavioral data. For event-related potentials (ERP), we detected two well-established old/new effects related to memory retrieval under both neutral and emotional conditions: the frontal negativity (FN400) related to familiarity-driven recognition and the late posterior negativity (LPN) related to reconstructive processing or evaluation of retrieval outcomes. More importantly, the old/new effects were missing for incongruent condition during the early stage of FN400 (300-400 ms). Besides, for LPN (700-900 ms), the old/new effects of the incongruent condition are greater than the congruent condition. The results prove that the encoding phase's emotional congruency factor has a regulatory effect on the retrieval phase's early familiarity processing and evaluation of retrieval outcomes. Our data confirm the inhibitory effect of emotional conflict control on memory retrieval and support the emotional conflict control mechanism found in previous studies.

Keywords: FN400; LPN; emotional conflict; event-related potentials; recognition memory.