Abstract Introduction: Posttraumatic stress disorder (PTSD) is a highly prevalent disorder with important social consequences. Several models have been developed with the aim of understanding the mechanisms underlying its symptoms. Intrusions are idiosyncratic symptoms that commonly take the form of involuntary recollection of images or flashbacks about the traumatic event. Objective: To review how memory is conceptualized in each of these models and the implications for clinical practice. Methods: A narrative review of the literature was conducted through analysis of the perspectives of memory in theoretical models of PTSD. Results: Two main perspectives were identified: 1) models in which specific mechanisms of memory for processing traumatic events are proposed, especially those based on clinical studies, and 2) models in which common mnemonic mechanisms are utilized to explain the phenomenon, primarily based on basic experimental research studies investigating memory. The different theories based on these approaches have led to distinct psychotherapy interventions. Conclusion: In order to clarify these discrepancies, future research should aim for the methodological rigor of experimental studies, while maintaining the ecological applicability of findings. Cognitive experimental psychopathology is therefore an area on which research funding should be focused. Such studies could elucidate the role of mnemonic aspects in PTSD and how they impact psychological treatments.