Novelty–retrieval–extinction paradigm to decrease high-intensity fear memory recurrence

The retrieval–extinction paradigm based on memory reconsolidation can prevent fear memory recurrence more effectively than the extinction paradigm. High-intensity fear memories tend to resist reconsolidation. Novelty–retrieval–extinction can promote the reconsolidation of fear memory lacking neuroplasticity in rodents; however, whether it could effectively promote high-intensity fear memory reconsolidation in humans remains unclear. Using 120 human participants, we implemented the use of the environment (novel vs. familiar) with the help of virtual reality technology. Novelty environment exploration was combined with retrieval–extinction in fear memory of two intensity levels (normal vs. high) to examine whether novelty facilitates the reconsolidation of high-intensity fear memory and prevents recurrence. Skin conductance responses were used to clarify novelty–retrieval–extinction effects at the behavioral level across three experiments. Retrieval–extinction could prevent the reinstatement of normal-intensity fear memory; however, for high-intensity fear memory, only the novelty–retrieval–extinction could prevent recurrence; we further validated that novelty–retrieval–extinction may be effective only when the environment is novel. Although the high-intensity fear memory is higher than normal-intensity in this study, it may be insufficient relative to fear experienced in real-world contexts or by individuals with mental disorders. To some extent, these findings indicate that the novelty–retrieval–extinction paradigm could prevent the recurrence of high-intensity fear memory, and we infer that novelty of environment may play an important role in novelty–retrieval–extinction paradigm. The results of this study have positive implications for the existing retrieval extinction paradigm and the clinical treatment of phobia.