Cardiorespiratory Fitness as Protection Against the Development of Memory Intrusions: a Prospective Trauma Analogue Study

Abstract

Intrusive and distressing memories are at the core of post-traumatic stress disorder (PTSD). Since cardiorespiratory fitness (CRF) has been linked with improved mental health, emotion regulation, and memory function, CRF may, by promoting these capabilities, protect against the development of intrusions after trauma. We investigated this idea in 115 healthy individuals, using a trauma film to induce intrusions. As potential mediators, we assessed indices of pre-trauma mental health such as heart rate variability, subjective and psychobiological peri-traumatic responses, and memory. Critically, results showed that higher CRF was related to fewer intrusions, but no mediators emerged of the CRF-intrusion relationship. These results indicate that individuals displaying higher CRF are less prone to develop traumatic memory intrusions. This suggests that promoting fitness prior to possible trauma exposure may provide a useful strategy to boost resilience against the development of debilitating re-experiencing symptoms of PTSD.

Time-dependent emotional memory transformation: divergent pathways of item memory and contextual dependency

“…Likewise, immediately after the experience of trauma, initial recognition of central trauma aspects conceivably does not require presence of the original encoding context either, and can be remembered in any potential context, given the strength of trauma memories. Since reduced contextual dependency of memory has been related to increased number and distress of analogue traumatic intrusions (Meyer et al, 2017;Voorendonk et al, 2021), the risk of distressing intrusions immediately after the occurrence of a traumatic event should therefore be high. Indeed, trauma analogue studies (Rattel et al, 2019) and clinical observations (O'Donnell et al, 2007) show that shortly after an emotional event reexperiences occur frequently.…”

Context reexposure to bolster contextual dependency of emotional episodic memory

“…This may manifest itself in symptoms that are characteristic of anxiety disorders and posttraumatic stress disorder (PTSD) such as fear generalization and intrusive images (Acheson et al, 2012;Brewin et al, 2010;Ehlers & Clark, 2000;Lambert & McLaughlin, 2019;Liberzon & Abelson, 2016). In support of this idea, experimental studies have demonstrated that reductions in contextual dependency of memory indeed predict the occurrence or distress of analogue trauma intrusions (Bisby et al, 2010;Meyer et al, 2017;Voorendonk et al, 2021). Insights into how contextual dependency of emotional memory can be targeted is therefore of significant clinical interest.…”