Emotion enhances metamemory judgments: An event-related potential comparison of judgments of learning and judgments...

In episodic memory, emotional items often can be remembered better than neutral ones, whereas this emotional salience effect is not observed in source memory (neutral extrinsic or contextual details). However, it remains unclear whether this dissociation is evident in subjective metamemory judgments-specifically judgments of learning (JOLs) and judgments of sources (JOSs). To reveal the effects of emotions on these two types of metamemory judgments and their neural mechanisms, we used different emotion (negative, positive, and neutral) pictures with neutral contextual details. Results revealed that both JOLs and JOSs showed emotional salience effects, supporting the universal role of emotion as a metamemory cue. Event-related potential (ERP) results revealed shared neural mechanisms underlying both judgment types: early automatic processing (evidenced by enhanced P200 and reduced N400) and late controlled processing (late positive components). Crucially, the neural activity within this shared subjective pathway was functionally dissociated from the encoding processes diagnostic of subsequent memory success. Both judgment types exhibited right-hemisphere lateralization for high versus low metamemory ratings. Nevertheless, JOLs elicited more widespread and sustained neural activity patterns than JOSs in both emotion-neutral contrasts and high-low rating differences. These findings support the Dual-basis theory of metamemory (experience-belief interaction) and suggest that item and source metamemory judgments rely on partially distinct neural mechanisms. This provides neurophysiological insights for optimizing metacognitive training strategies.