Association of attention and memory biases for negative stimuli with post-traumatic stress disorder symptoms

Cognitive models have highlighted attentional and memory biases to negatively valenced emotional stimuli, and their association, in the development and maintenance of post-traumatic stress disorder (PTSD). However, research has focused mainly on attentional biases towards distracting (not task-relevant) negative stimuli and the links of attentional biases with memory remain underexplored. We manipulated attention during encoding of trauma-irrelevant negative and neutral words and examined the differential relationship of their encoding and recall with PTSD symptoms. Responders to the World Trade Center disaster performed tasks in which they read negative and neural words (full attention, FA) and reported the color of another set of such words (divided-attention, DA). Subsequently, participants used word stems to aid retrieval of words shown in both tasks. PTSD symptoms were associated with slower performance for negative vs neutral words in FA but not DA tasks. Furthermore, greater PTSD symptoms severity was associated with more accurate recall of negative vs neutral words, irrespective of whether words were presented on FA or DA tasks. These findings suggest that PTSD symptoms in a trauma-exposed population are related to encoding of trauma-irrelevant negative information when attention is fully deployed and subsequent recall of negative information, irrespective of whether attention was fully deployed.