Influence of acute stress on attentional bias toward threat: How a previous trauma exposure disrupts threat apprehension.

While previous trauma exposure is known to be a risk factor for the development and maintenance of many psychological disorders, it remains unclear how it increases individual risk for prospective psychopathology in the aftermath of a new trauma exposure. The aim of this study was to investigate how a prior exposure to trauma affects attentional processing of threat before and after an acute stress task. Specifically, we assessed attentional biases to threat before and after a cold pressor task in 17 individuals who have been exposed to trauma (TE) compared to 18 individuals without trauma exposure (NTE). Behavioral results showed difficulties to disengage from threat in TE but not in the control group prior to stress induction, as well as a switch to an attentional bias toward threat after the cold pressor task in the TE group. For the ERPs, we highlighted (1) decreased N1 negativity in response to threatening stimuli after an acute stress in both groups, and (2) a parallel increase in P1 for such stimuli only in the TE group. Those results suggest a vulnerability presented by previously traumatized individuals when dealing with threats as well as an acute responsitity toward stress. Those results are interpreted in regards with the theorical models of stress and anxiety.