Attention bias variability as a cognitive marker of PTSD: A comparison of eye-tracking and reaction time methodologies

Identification of reliable behavioral markers for posttraumatic stress disorder (PTSD) can offer objective measures beyond self-reports to aid in diagnosis, treatment, and prevention. Attention bias variability (ABV), defined as fluctuations in attention toward or away from threat-related stimuli, has been associated with PTSD. Reaction time-based ABV (RT-ABV) has been extensively studied and shown to be linked with PTSD symptomatology. An eye-tracking-based ABV index (ET-ABV) was only recently introduced, and results show that it may be associated with trauma exposure rather than with PTSD symptoms. However, these two ABV types have yet to be studied within the same sample. The current study explored the association between trauma exposure, PTSD symptom severity, and ABV measures, applying both the classic RT-ABV and the new ET-ABV in the same sample. Participants with PTSD (n = 41), trauma-exposed healthy controls (TEHC; n = 71), and non-trauma-exposed healthy controls (HC; n = 38) completed an eye-tracking free-viewing matrix task and a response-based dot-probe task using the same threat-related stimuli (angry faces) across tasks. Results indicate that both RT-ABV and ET-ABV were significantly higher in participants with PTSD compared to participants in the TEHC and HC groups, with no significant difference between the latter groups. Additional analyses indicate that although moderately correlated, each of the ABV measures explains unique portions of the variance in PTSD severity. This study replicates and extends prior findings on the association between ABV and PTSD and highlights the potential of ET-ABV as a novel and reliable marker for PTSD severity.