Event Memory Is Strengthened and Integrated by Review: Retrieval Practice Offers Inconsistent Additional Benefit

<p>Retrieval practice enhances memory relative to restudy (the testing effect) and is proposed to preferentially integrate related information. However, whether these effects generalize to more-naturalistic events remains unclear, as the mechanisms recruited during review may depend on how underlying memories are structured. Across three pre-registered experiments (N=122), we tested whether retrieval practice selectively enhances memory for, and integration of, related naturalistic episodes. Participants encoded person-object-location events organized into related pairs sharing object identity and location category. Event pairs were reviewed via retrieval practice, restudy, or no review (Experiment 1 only), followed by a delayed memory and integration test after nocturnal sleep. The classic testing effect was weak-to-absent: retrieval practice enhanced subjective event memory relative to restudy, but showed no reliable objective memory advantage (recognition of person-location and person-object associations), and both review conditions outperformed no-review control on both measures. Evidence for a retrieval-specific integration advantage was similarly limited: in Experiment 1, retrieval practice enhanced associative inference (linking people across related events) relative to restudy and no-review control, but this advantage over restudy did not replicate in Experiments 2–3; both review conditions increased misattribution errors (details incorrectly attributed across paired events) relative to no-review control. Despite these inconsistent condition-level effects, integration and objective memory consistently covaried such that events with better objective memory were also more integrated with their pair mate. Together, retrieval practice's advantage over restudy, where present, was narrow and context-dependent, whereas integration-memory associations were more robust, suggesting integration broadly supports memory without retrieval practice preferentially promoting it.</p>