Investigating the Cognitive Neural Mechanisms of Socially Shared Retrieval-Induced Forgetting: Insights from Behavioral and Electrophysiological Evidence

Background: Social cognition research increasingly emphasizes cognitive processes in social contexts, with growing attention to socially shared retrieval-induced forgetting (SS-RIF). Behavioral evidence suggests that the mechanisms of SS-RIF are fundamentally aligned with those of retrieval-induced forgetting (RIF). However, SS-RIF differs from RIF due to the influence of social interaction factors. This study investigated the cognitive neural mechanisms of SS-RIF, focusing on its commonalities and distinctions from RIF. Methods: Experiment 1 examined neural evidence associated with retrieval-related processes. Twenty-eight university students participated in a within-subject design including retrieval practice, social retrieval practice, and baseline conditions. Correct recall rates and P2/FN400 amplitudes were measured. Experiment 2 investigated the temporal dynamics of inhibitory mechanisms by narrowing the design to SS-RIF only, using a within-participant design with first, second, and third repetition blocks occurring within the social retrieval phase, and recall was tested across two days. Results: Classic RIF and SS-RIF effects were observed, accompanied by neural activity indicative of inhibition during both retrieval practice and social retrieval conditions. These findings are consistent with the hypothesis that SS-RIF and RIF may share overlapping underlying cognitive operations. Typical RIF and SS-RIF phenomena were also observed across repetition conditions, while neural data showed no significant differences in P2 and FN400 amplitudes for SS-RIF, highlighting a distinction from patterns observed in RIF. Conclusions: Cognitive suppression accounts offer a compelling framework for explaining SS-RIF during social retrieval practice. However, compared with RIF, the duration of inhibition differs in SS-RIF. Unlike RIF, SS-RIF shows no reduction in specific EEG signal amplitudes over time. These findings provide cognitive neural evidence for inhibitory mechanisms in social retrieval and preliminary insights into the shared and distinct mechanisms of socially shared and individual RIF.