Exploring the spatio-temporal functional connectome in PTSD: evidence of static and dynamic network alterations

Abstract

Few studies with substantial sample size have investigated the neural pathophysiology of post-traumatic stress disorder (PTSD). We aimed to characterize both static and dynamic functional network connectivity (dFNC) in a large, homogeneous, treatment-naïve PTSD cohort. Resting-state fMRI data from 70 PTSD patients and 68 demographically matched, trauma-exposed control (TEC) participants were analyzed using independent component analysis (ICA) and a sliding-window k-means clustering approach. PTSD patients exhibited widespread alterations in both static intrinsic functional connectivity (iFC) and dFNC, spanning frontoparietal, subcortical, and visual networks. Variations in static iFC were significantly correlated with symptom severity (primarily measured by Clinician-Administered Posttraumatic Stress Disorder Scale and Hamilton Anxiety Rating Scale scores). Significant group differences in dFNC connectivity patterns were identified in six of the seven dynamic states (States 1–3 and 5–7), while no significant between-group differences were observed in the temporal properties (fractional occupancy, mean dwell time, and transition rates) across any of the states. These convergent results provide additional evidence for iFC and dFNC dysregulation in PTSD, suggesting that network-level abnormalities particularly within frontoparietal, primary sensory and subcortical systems may contribute to the neural mechanisms of the disorder. Not applicable.