Taking a walk through time: aversive memory re-experiencing may be linked to spatio-temporal distance

Abstract

Background: Individuals with posttraumatic stress disorder (PTSD) often report intrusive memories that appear to lack the appropriate spatio-temporal context. Objective: We examined whether focusing on the spatio-temporal context of aversive autobiographical memories reduces negative emotions, appraisals, and re-experiencing symptoms. Methods: We recruited 109 healthy adults and had them rate emotionality, vividness, and re-experiencing of an aversive autobiographical memory. Furthermore, we assessed automatic associations of idiosyncratic memory triggers with the concepts ‘past’ vs. ‘now’, and self-reported sense of memory closure and distancing. To manipulate spatio-temporal memory (re-)organization, the experimental group (n = 53) performed a lifeline exercise in virtual reality (VR), where participants symbolically placed memory triggers along a path representing their own personal life story. The control group (n = 56) completed a non-personalized VR task. Results: We found a marked decrease in negative emotions, negative appraisals, and re-experiencing in the following week, but on average, the lifeline exercise was not superior to the control condition. However, those in the lifeline group with stronger trigger-past associations subsequently exhibited a more pronounced reduction in re-experiencing. Also, participants with a higher subjective sense of memory distancing reported less re-experiencing. Conclusions: The findings lend tentative support for theoretical assumptions about PTSD, but the potential causal role of automatic associations with spatio-temporal information remains to be clarified.