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

Abstract

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.

Keywords: Cognitive control; Heart rate; IES; Intrusive memories; Trauma film paradigm.

Fig. 1

Visualization of trauma-analogue paradigm and follow up. Note. T1: After we measured participants’ baseline inhibition, they watched trauma-analogue and control scenes while their electrocardiogram was recorded. After each scene, participants rated the emotions felt during the exposure. T2: Participants came back to the lab after a delay for a cognitive-interference task in which reminders from the movie scenes or non-reminders were presented preceding trials which varied in cognitive control demands. From the first to the sixth day after trauma-analogue exposure participants reported potential intrusive memories. On day 7 participants filled out the Impact of Event scale.

Fig. 2

Example trial of the cognitive-interference task (T2). Note. The trial following the reminder or non-reminder would take either the form of a congruent, a baseline or an incongruent trial in a counter-balanced manner. For purpose of display examples of all conditions are shown. The task-irrelevant reminder / non-reminder, either negative or neutral, would be followed by a fixation cross. The subsequent task-relevant trial required the participant to quickly count the number of symbols presented. The trials varied in cognitive control demand, with congruent trials displaying digits matching the number of symbols, a baseline condition using hashtag symbols, and incongruent trials showing digits mismatched with the symbol count. The image shown is for illustrative purposes and was not part of the original stimulus material used in the study.

Fig. 3

Mean Memory intrusion frequency and intrusion quality over six days following T1. Note. Ratings for intrusion frequency and quality are averaged over participants (frequency was measured with 0–4+; distress and vividness with a sliding scale from 0 to 100). Intrusions were assessed daily for six days, beginning 24 h after participants left the lab after the trauma-analogue exposure at T1.

Fig. 4

Reaction times for incongruent trials with primes grouped by valence. Note. The y-axis represents the mean reaction time scores (ms = milliseconds) for facilitating interpretation, though all analyses were done with log-transformed median reaction times per participant and condition. Error bars represent the standard errors. *p < .05; **p < .01; *** p < .001.

Fig. 5

Mean Magnitude Effect for negative reminders versus negative non-reminders between groups with more versus less self-assessed event impact. Note. Event Impact measured with Impact of Event scale (IES), ms = milliseconds, * p < .05.