WITHDRAWN: Precuneal and amygdala spontaneous activity and functional connectivity in war-zone-related PTSD

Real-Time fMRI Neurofeedback with War Veterans with Chronic PTSD: A Feasibility Study

Many patients with post-traumatic stress disorder (PTSD), especially war veterans, do not respond to available treatments. Here, we describe a novel neurofeedback (NF) intervention using real-time functional magnetic resonance imaging for treating and studying PTSD. The intervention involves training participants to control amygdala activity after exposure to personalized trauma scripts. Three combat veterans with chronic PTSD participated in this feasibility study. All three participants tolerated well the NF training. Moreover, two participants, despite the chronicity of their symptoms, showed clinically meaningful improvements, while one participant showed a smaller symptom reduction. Examination of changes in resting-state functional connectivity patterns revealed a normalization of brain connectivity consistent with clinical improvement. These preliminary results support feasibility of this novel intervention for PTSD and indicate that larger, well-controlled studies of efficacy are warranted.

Reduced default mode network connectivity following combat trauma

Recent studies show decreased functional connectivity in the default mode network (DMN) in PTSD; however, few have directly examined combat trauma specifically. There is limited understanding of how combat itself may affect the DMN. Some literature suggests that trauma exposure, rather than PTSD, can disrupt the DMN. To further elucidate the effect of trauma and PTSD on the DMN, we investigated DMN functional connectivity during the resting-state in veterans with PTSD, combat-exposed controls, and never-traumatized healthy controls. Results revealed that DMN connectivity was reduced in veterans exposed to combat trauma with and without PTSD compared to healthy civilian controls. Specifically, both groups of veterans demonstrated weaker connectivity within a network involving the precuneus, medial prefrontal cortex (mPFC) and right superior parietal lobule regardless of whether the mPFC or precuneus was chosen as a seed region. Findings suggest that the experience of trauma, rather than the pathology of PTSD, may be related to DMN changes.

Altered resting-state functional connectivity of the amygdala in Chinese earthquake survivors

Posttraumatic stress disorder (PTSD) is linked to abnormal amygdala activities. This study measured amygdala functional connectivity using DSM-5 criteria. There were 33 participants in the PTSD group and 33 participants in a trauma-exposed control (TEC) group, who did not have PTSD according to the PTSD checklist of the DSM-5 (PCL-5). Our findings are as follows: (1) In the PTSD group, the amygdala had increased positive connectivity with the medial prefrontal cortex (mPFC) and hippocampus, and decreased positive connectivity with the inferior mPFC and insula. The amygdala had increased negative connectivity with the orbital prefrontal cortex and decreased negative connectivity with the insula in comparison with TEC group. (2) PCL of all participants was correlated with the connectivity between the amygdala and the mPFC, hippocampus, and insula. These regions overlapped with those identified in the between-group comparisons. However, there was no association between PCL of the PTSD group and connectivity in these regions. Abnormal functional connectivity between the amygdala and mPFC subdivisions, hippocampus, and insula reveals their importance in PTSD pathogenesis.