Trauma-analogue symptom variability predicted by inhibitory control and peritraumatic heart rate.

The reasons why some individuals who experience trauma develop post-traumatic stress disorder (PTSD) while others do not remain poorly understood, highlighting the complex interplay of encoding-related and intrapersonal factors. This study aimed to examine factors predicting variability in trauma-related symptom development. Using a trauma film paradigm in a healthy sample (N = 32), we investigated how inhibitory control and peritraumatic responses relate to the development of intrusive memories and self-assessed event impact. Peritraumatic heart rate was associated with more frequent, vivid, and distressing memory intrusions during the week following trauma-analogue exposure. It also predicted hyperarousal and avoidance symptoms, with the latter further linked to lower inhibitory control. In a cognitive-interference task conducted approximately one day after trauma-analogue exposure, negative trauma reminders increased response latencies. This reduced interference control was predicted by both lower inhibitory control and higher peritraumatic heart rate, and it was especially pronounced in individuals who reported a heightened overall event impact. In conclusion, inhibitory control and peritraumatic heart rate emerged as predictors of subsequent reminder interference, intrusions, and self-assessed event impact. These findings provide insights into physiological and behavioural mechanisms underlying variability in the development of trauma-analogue symptoms and related cognitive interference when exposed to trauma reminders in a healthy sample without a trauma history.