Trauma-Related Patterns of Threat Discrimination and Arousal: Insights from a VR Contextual Conditioning Paradigm

Exposure to trauma can impair the ability to distinguish safe contexts from dangerous ones, a hallmark of post-traumatic stress disorder (PTSD). Trauma-exposed (TE) individuals also often show heightened autonomic responses to both trauma-related cues and general stressors compared to trauma-naïve (TN) individuals. However, few studies examine how physiological reactivity differs between those who succeed or fail in discriminating safe and threatening contexts, and how trauma exposure impacts this ability. This study assessed threat discrimination and electrodermal activity (EDA) in TE (n = 17) and TN (n = 18) individuals to isolate the effects of trauma on these outcomes. Participants (mean age = 29.06 years; 54.3% female; 45.7% Asian) completed a virtual reality context-conditioning task with a "danger zone" (shocks applied) and a "safe zone" (shock-free). EDA, measured through skin conductance response (SCR) and skin conductance level (SCL), was recorded, and threat discrimination learning was evaluated via task-related questions. Results indicated similar threat discrimination abilities between TE and TN individuals, with comparable numbers of learners and non-learners in either group. TE and TN individuals showed no differences in SCL, regardless of learning status, though TE had lower overall SCR. Nonetheless, among learners, both groups demonstrated higher SCR in the danger zone than the safe zone. These findings suggest that trauma exposure may not impair threat discrimination learning, but may blunt physiological reactivity to acute threats. Future research could explore how trauma history, cognitive styles, and neurobiological factors shape threat learning and arousal.