Effects on intrusive memories of playing Tetris with or without simultaneous and deliberate memory recall

Two interventions that tax visuospatial working memory (WM) may reduce intrusive memories despite differing procedurally: playing Tetris with or without memory recall. Accordingly, this study examined how engagement with negative memories influences intrusion frequency (Experiment 1) and WM load (Experiment 2). In Experiment 1 (N = 90), participants viewed a trauma film and were assigned to Tetris without memory recall, Tetris with memory recall, or a no-task control condition. Participants rated memory vividness and unpleasantness before and after the intervention and recorded film-related intrusions in a diary for 1 week. In Experiment 2 (N = 45), a reaction time task assessed whether brief memory reactivation (as used in the Tetris without memory recall condition) or concurrent, deliberate recall (as used in the Tetris with memory recall condition) differentially taxed WM. Experiment 1 showed that the Tetris with memory recall task led to the largest reductions in memory vividness, η_p ² = .09, p = .017, and unpleasantness, η_p ² = .09, p = .015, relative to the other conditions, but, unexpectedly, intrusion frequency did not differ between interventions, η_p ² = .02, BF₀₁ = 5.57, p = .448. Experiment 2 indicated that only simultaneous, deliberate recall imposed a WM load, η_p ² = .11, p = .032. The lack of effects on intrusive memories warrants consideration of methodological differences between this and prior Tetris research and highlights the need to clarify which elements and mechanisms of the intervention-whether implemented with or without deliberate recall-modulate intrusions before translating these findings into clinical practice.