A systematic review and meta-analysis of the effectiveness of experimental techniques in altering intrusive memories of lab-analogue trauma

Abstract

Abstract Experiencing trauma can lead to intrusive memories, a hallmark symptom of post-traumatic stress disorder and transdiagnostic feature of stress-related disorders. Understanding why intrusions increase or decrease is pivotal in developing effective interventions to safeguard mental wellness following trauma. Building on lab-analogue trauma paradigms, we conducted a pre-registered (PROSPERO: CRD42021224835)meta-analysis to investigate the effectiveness of experimental techniques in either reducing or increasing intrusion frequency (e.g., assessed with a daily diary), intrusion-related distress and symptoms. Aggregating data from 126 articles examining 118 techniques with 584 effect sizes and 11,132 participants, we found that techniques hypothesized to reduce intrusion frequency significantly decreased intrusion frequencies, intrusion-related distress and symptoms (g = 0.11— 0.49). Moreover, techniques hypothesized to increase intrusions significantly increased intrusion frequencies and their associated distress (g = -0.15 — -0.19). Moderator and focal analyses showed that behavioral techniques tapping into imagery-based processing (e.g. playing Tetris following trauma reminder) were most effective in reducing intrusion frequency and symptoms (g = 0.22 — 0.68). However, those targeting verbal-based processing (e.g., rumination, adding contextual information) significantly increased intrusions, albeit to a small degree (g = -0.29 — -0.30). We further supplement the meta-analysis with a website that allows researchers to analyze the dataset to facilitate research synthesis and future endeavor. While techniques that reduce intrusions can inform the development of evidence-based interventions to reduce intrusions in real life, techniques that may (inadvertently) increase intrusions underscore vulnerabilities factors and thus can inform preventive measures.