Intranetwork and internetwork functional connectivity alterations in post-traumatic stress disorder

Background: A large number of previous neuroimaging studies have explored the functional alterations of post traumatic stress disorder (PTSD). However, abnormalities in the functional architecture of resting-state networks in PTSD were rarely elucidated. Methods: This study used independent component analysis to explore the resting state intranetwork and internetwork functional connectivity differences between 20 PTSD patients and 20 matched healthy controls (HCs). Results: Selective alterations of intranetwork and internetwork intrinsic functional connectivities were found in the PTSD patients. Compared with HCs, the PTSD patients exhibited significantly decreased network connectivity within the anterior default mode network, posterior default mode network (pDMN), salience network (SN), sensory motor network, and auditory network. Furthermore, the PTSD patients exhibited increased internetwork connectivity between SN and pDMN. Limitations: This study lacked recruitment of trauma exposed HCs, which limits our ability to determine whether the alterations are caused by PTSD or trauma exposure. Conclusion: The findings suggested that the PTSD patients exhibited abnormal functional connectivity at the brain network level. Notably, the enhanced internetwork connectivity between SN and pDMN in the PTSD patients may be associated with hyperarousal and heightened anxiety in PTSD. (C) 2015 Elsevier B.V. All rights reserved.