I think I will forget: exploring the relationship between posttraumatic stress disorder symptoms and prospective memory in everyday life.

People with Posttraumatic Stress Disorder (PTSD) symptoms often report impaired prospective memory (PM) - the ability to remember future intentions. However, evidence for the relationship between PTSD symptoms and PM performance in the general population varies by assessment method. To minimise self-report biases and maximise ecological validity and experimenter control, we developed a novel, naturalistic PM paradigm - Modified-Actual Week - to assess naturalistic PM performance. Our non-clinical student/community sample (N = 262) completed 16 researcher-dictated PM tasks over four days and reported subjective PM, PTSD symptoms, and metacognitive beliefs (i.e. beliefs about own cognitive processes, including confidence in memory ability). We examined the relationship between PM and PTSD symptoms and whether metacognitive beliefs might partially explain this relationship. PM performance was unrelated to PTSD symptom severity but was weakly correlated with metacognitive beliefs. For PTSD symptom clusters, only hyperarousal correlated significantly with PM performance. Self-report PM showed a small correlation with PM performance, which was stronger among people with higher PTSD symptoms. The results indicate that subjective PM complaints in relation to PTSD symptoms are more closely tied to metacognitive beliefs than to measurable performance deficits, highlighting a dissociation between self-report and performance-based PM measures in the context of PTSD symptoms.