Event-related potential evidence for memory prioritization modulated by social labels

OBJECTIVE: We investigated whether semantic activation induced by social labels modulates memory prioritization during encoding, as indexed by event-related potentials (ERPs). Specifically, we examined semantic processing and attentional allocation during encoding to identify the stage at which memory enhancement arises. METHODS: The experiment consisted of a semantic categorization task during encoding followed by a surprise free-recall test. Participants were assigned to one of two task conditions. In task 1, they judged whether a word belonged to the self category or to non-self categories (friend, irrelevant). In task 2, they judged whether a word belonged to the self or friend category. RESULTS: We analyzed the N400 and P3b components of ERP data recorded during encoding. Greater N400 attenuation was observed in the self condition in task 1 but not in task 2. Parietal P3b amplitude was larger in the self condition than in the friend and the irrelevant conditions. In the surprise free-recall test, recall performance was highest for self items followed by friend items, and lowest for irrelevant items. CONCLUSION: Recall performance demonstrated both a self-prioritization effect and a friend advantage. These results indicate that self-prioritization is more strongly associated with attentional allocation during encoding than with task-driven semantic processing.