A Network-Based Neurobiological Model of PTSD: Evidence From Structural and Functional Neuroimaging Studies
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Purpose of Review
Although a fine-grained understanding of the neurobiology of posttraumatic stress disorder (PTSD) is yet to be elucidated, the last two decades have seen a rapid growth in the study of PTSD using neuroimaging techniques. The current review summarizes important findings from functional and structural neuroimaging studies of PTSD, by primarily focusing on their relevance towards an emerging network-based neurobiological model of the disorder.
PTSD may be characterized by a weakly connected and hypoactive default mode network (DMN) and central executive network (CEN) that are putatively destabilized by an overactive and hyperconnected salience network (SN), which appears to have a low threshold for perceived saliency, and inefficient DMN-CEN modulation.
There is considerable evidence for large-scale functional and structural network dysfunction in PTSD. Nevertheless, several limitations and gaps in the literature need to be addressed in future research.
KeywordsPosttraumatic stress disorder Default mode network Central executive network Salience network Functional magnetic resonance imaging Structural MRI
The authors would like to thank the US Department of Veterans Affairs National Center for PTSD, the NIMH, and the Brain and Behavior Foundation for their support. We would also like to thank our colleagues for their thoughtful conversation while preparing this manuscript.
This work was supported by the US Department of Veterans Affairs (DVA) National Center for PTSD, NIH [MH-101498]; Brain and Behavior Foundation Young Investigator Award [NARSAD]. The content is solely the responsibility of the authors and does not necessarily represent the official views of the sponsors. The sponsors had no role in the preparation, review, or approval of the manuscript.
Compliance with Ethical Standards
Conflict of Interest
Teddy J. Akiki and Christopher L. Averill declare that they have no conflict of interest.
Chadi G. Abdallah has received grants from the NIH [MH-101498], the Brain and Behavior Foundation Young Investigator Award [NARSAD], and the US Department of Veterans Affairs (DVA) National Center for PTSD. Dr. Abdallah has served as a consultant or on advisory boards for Genentech and Janssen. He also serves as editor for the journal Chronic Stress published by SAGE Publications, Inc.
Human and Animal Rights and Informed Consent
This article does not contain any studies with human or animal subjects performed by any of the authors.
Papers of particular interest, published recently, have been highlighted as: • Of importance
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