Clinical Correlates of Resting-State Functional Magnetic Resonance Imaging in Military Personnel with Adulthood—Onset War—Related Post—Traumatic Stress Disorder
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Clinical Correlates of Resting-State Functional Magnetic Resonance Imaging in Military Personnel with Adulthood—Onset War—Related Post—Traumatic Stress Disorder
Investigation of the neural substrates of post-traumatic stress disorder (PTSD) in military personnel using whole-brain approaches remains scarce, hindering the development of circuit-based neuromodulatory interventions.
Objectives:
This study aimed to identify potential associations between clinical symptoms and whole-brain resting-state functional connectivity with magnetic resonance imaging in military personnel with adulthood-onset war-related PTSD.
Methods:
Thirty-seven soldiers from the Canadian Armed Forces with moderate to severe treatment-resistant PTSD participated in this study. We assessed PTSD, anxiety and depressive symptoms, quality of life, and time since trauma. We characterized the whole-brain functional connectome using independent component analysis and regions of interest (ROI)-to-ROI connectivity, as well as its topology using graph theory.
Results:
Greater severity of PTSD and anxiety symptoms was associated with lower connectivity (r < 0) between the default mode network (DMN) and frontoparietal network. Greater severity of PTSD symptoms was also associated with a higher nodal clustering coefficient of the inferior parietal lobule from the DMN. Greater severity of anxiety symptoms and longer time since trauma was the only clinical variables that correlated with higher connectivity patterns, all involving the visual networks (the frontoparietal-visual, the visual-DMN, and within-visual networks).
Conclusions:
This work contributes to identifying brain targets for the development of personalized neuromodulatory interventions. In particular, the DMN may be a promising target to alleviate PTSD symptoms, and the visual network may be a target to treat comorbid anxiety symptoms.
Impact Statement
This work aimed to identify clinical correlates of resting-state functional connectivity in military personnel with post-traumatic stress disorder (PTSD) refractory to psychotherapy and pharmacotherapy (N = 37). Our findings indicate that increasing connectivity between the default mode and frontoparietal networks may be a promising therapeutic target to alleviate PTSD symptoms with personalized neuromodulatory interventions, whereas reducing connectivity within the visual network may constitute a target to treat comorbid anxiety. They also emphasize the importance of investigating clinical correlates using whole-brain methods to uncover new target engagement for therapeutic brain circuitry candidates.
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