Patients with post-traumatic stress disorder (PTSD) have shown disturbances in visual information treatment. However, most of studies demonstrated attentional bias towards emotional stimuli by using non-ecological paradigm. The paradigm of change blindness offers the possibility of studying sensitivity to the sudden irruption of visual information with ecological stimuli.

To compare the explicit detection with the implicit detection by using respectively motor response and eye tracking in patients with PSTD and controls.

Fifteen patients with PTSD and fifteen healthy controls had to detect changes in 96 scenes with (1) no change, (2) one neutral change or (3) one emotional pleasant or unpleasant change. We measured the participant's speed and accuracy in explicitly reporting the changes via motor responses, and their capacity to implicitly detect changes via eye movements.

The patients showed a trend towards slower explicit detection for the emotional change (P = 0.06) and more specifically for unpleasant change (P = 0.054). The two groups did not differ for implicit detection.

Patients tend to explicitly detect more slowly emotional change (but not neutral), especially for unpleasant change. This could be the result of a lack of access to consciousness of the emotional information. The emotional visual information treatment in PSTD could require more attentional processes than the non-emotional visual information and then lead to a decrease of the available attentional resources for the explicit task.

The authors have not supplied their declaration of competing interest.