Dissociation between cognition and emotion regulation in patients with post-traumatic stress disorder: A combined gray matter volume and a delayed-response working memory task

Abstract

Abstract Post-traumatic stress disorder (PTSD) has been associated with cognitive and emotional dysregulation for inhibitory control, yet currently, there are no validated methods for dissociation between cognition and emotion regulation in patients with PTSD. Thus, this study evaluated the differential brain activation patterns associated with cognitive and emotional distractors during working memory (WM) maintenance for human faces between patients with PTSD and healthy controls (HCs) and assessed the relationship between changes in the activation patterns by the opposing effects of distraction types and gray matter volume (GMV). Twenty-four patients with PTSD and 24 HCs underwent T1-weighted magnetic resonance imaging (MRI) and event-related functional MRI (fMRI). PTSD symptoms were evaluated using the Clinically Administered PTSD Scale. Event-related fMRI data were recorded while subjects performed a delayed-response WM task with human face and trauma-related distractors. Compared to the HCs, the patients with PTSD showed significantly reduced GMV of the inferior frontal gyrus (IFG) and significantly higher GMV of the inferior temporal gyrus (p < 0.05). In the delayed-response WM tasks, the patients showed significantly increased activities in the superior temporal gyrus (STG) and middle temporal gyrus compared with HCs during a maintenance trial (p < 0.05). For the human face distractor trial, the patients showed significantly decreased activities in the superior frontal gyrus and IFG compared with HCs (p < 0.05). In addition, the patients showed lower scores and slower reaction times for the face recognition task with trauma-related distractors compared with HCs and showed significantly increased activities in the middle frontal gyrus and STG during the trauma-related distractor trial (p < 0.05). Differential brain activation patterns associated with the effects of distraction in PTSD patients may be linked to neural mechanisms with impairments in cognitive control for confusable distractors and in the ability to control emotional distraction.