Abstract
Exposure to stress and trauma is associated with military deployments, leading to a high prevalence of Posttraumatic Stress Disorder (PTSD). PTSD is associated with an attentional bias toward threatening stimuli and scanning behavior which is indicative of hypervigilance in the context of static scenes. Work exploring the impact of PTSD on visual attention during natural viewing of a threatening environment, is limited. Our recent work revealed that PTSD impacted eye-movement during a low-threat visual search task in an open virtual environment (VE) where cognitive load was increased, suggesting PTSD impacts visual attention. Here, we extended this work by developing stress-inducing VEs, where eye-movement was recorded from military personnel (active duty/veteran) with and without PTSD during a self-paced search task in four different open-world desktop VEs, that varied by stress (high/low) and theme (neutral/military). High-stress conditions included flashbangs and context-consistent sounds (e.g., loud gunfire or heavy construction). Low-stress conditions had no flashbangs and scenic sounds (e.g., birds). Preliminary results (N = 6 per group) found that the PTSD group had significantly increased individual fixation and blink durations, decreased fixation and saccade rates, and more horizontal saccades. Additionally, we observed an interaction where the Non-PTSD group showed larger differences in eye-movement behavior between the high and low-stress conditions, compared to the PTSD group. Thus far, our stress-inducing VEs appear to elicit noticeable differences in eye-movement between PTSD and Non-PTSD individuals. Preliminary findings suggest those with PTSD may be hypervigilant towards threatening objects regardless of the stress condition, supporting the theory of an attentional bias towards threats. This work will allow us to evaluate how stress impacts deployment of overt attention, which is critical for understanding how military personnel may function when completing duty relevant tasks.