(PS10-32) PTSD Symptom Clusters and Brain Networks: A Resting State Functional Connectivity Study

Abstract Text: Post-Traumatic Stress Disorder (PTSD) is a stress-related disorder that may develop following exposure to traumatic events and is characterized by three core symptom clusters: re-experiencing (Cluster B), avoidance/numbing (Cluster C), and hyperarousal (Cluster D). Resting state functional connectivity (rsFC) has provided critical insights into the neural mechanisms underlying PTSD through distinct brain networks, including the default mode network (DMN), affective network (AN), and salience network (SN). These networks are critical for self-referential processing, emotional regulation, and threat detection, all of which are disrupted in PTSD. While connectivity variation among these networks has been defined in PTSD, little work has investigated how they may relate to the diagnostic criteria of the disorder. In addition, the AN has yet to be investigated in relation to these Clusters, despite substantial evidence indicating its role in PTSD symptom experience. A better understanding of these relationships may have clinical implications and aid in individualized intervention determination. The present study examined the relationships between PTSD diagnostic Cluster scores and rsFC alterations in the DMN, AN, and SN in women with PTSD as a result of interpersonal violence (physical or sexual). Sixty-five participants completed the Life Events Checklist, Clinician-Administered PTSD Scale for DSM-IV-TR, and functional magnetic resonance imaging. Differences in rsFC were assessed by conducting voxelwise linear regressions using network node z-score correlation maps (3dttest++). Preliminary results indicated that CAPS cluster scores were significantly correlated to total PTSD symptom severity. In addition, connectivity between regions of the SN (anterior insula–rostral prefrontal cortex) was negatively correlated with Cluster D scores (peak MNI: -29.5, -54.5, 0.5; t = 3.47, pFWE < .05). Future analyses will examine the specific relationships between total PTSD symptom severity and Cluster scores with brain network connectivity. We will also test the strength of relationships between rsFC within the brain networks and PTSD Cluster scores.