Attention to novel and target stimuli in trauma survivors.

Trauma and its consequences can have lasting biological and cognitive effects on those who experience them. This study investigated the extent to which trauma, posttraumatic stress disorder (PTSD), and dissociation influenced attention to basic auditory stimuli in a sample of military cadets. After filling out a series of psychometric questionnaires, 27 male military cadets varying in their trauma history participated in the "novelty" oddball task in which participants were asked to count high-pitched tones while ignoring other auditory stimuli. Electroencephalogram (EEG) was continually recorded in order to assess P300 responses, an event-related potential (ERP) associated with attention and memory processes. Trauma history only, and not dissociation or PTSD scores, predicted smaller P300 amplitudes to target tones. To distracting novel sounds, only trauma history and dissociation predicted unique variance in P300 amplitudes. The findings suggest that PTSD may not be central to the attentional disturbances found in traumatized samples, while trauma history and dissociation may play a more important role. Future studies investigating attentional processes post trauma should utilize dissociation scales and a non-trauma sample.