Battlefield-like stress following simulated combat and suppression of attention bias to threat.

BACKGROUND Acute stress disorder involves prominent symptoms of threat avoidance. Preliminary cross-sectional data suggest that such threat-avoidance symptoms may also manifest cognitively, as attentional threat avoidance. Confirming these findings in a longitudinal study might provide insights on risk prediction and anxiety prevention in traumatic exposures. METHOD Attention-threat bias and post-traumatic symptoms were assessed in soldiers at two points in time: early in basic training and 23 weeks later, during advanced combat training. Based on random assignment, the timing of the repeat assessment occurred in one of two schedules: for a combat simulation group, the repeat assessment occurred immediately following a battlefield simulation exercise, and for a control group, the assessment occurred shortly before this exercise. RESULTS Both groups showed no threat-related attention bias at initial assessments. Following acute stress, the combat simulation group exhibited a shift in attention away from threat whereas the control group showed no change in attention bias. Stronger threat avoidance in the combat simulation group correlated with severity of post-traumatic symptoms. Such an association was not found in the control group. CONCLUSIONS Acute stress may lead some individuals to shift their attention away from threats, perhaps to minimize stress exposure. This acute attention response may come at a psychological cost, given that it correlates with post-traumatic stress disorder (PTSD) symptoms. Further research is needed to determine how these associations relate to full-blown PTSD in soldier and civilian populations.