Disrupted brain network topology in pediatric posttraumatic stress disorder: A resting-state fMRI study
Xueling Suo1, Du Lei1, Kaiming Li1
1Huaxi MR Research Center (HMRRC), Department of Radiology, West China Hospital of Sichuan University, Chengdu, Sichuan, China.
Insights
Pediatric posttraumatic stress disorder (PTSD) shows altered brain functional connectome topology, shifting towards regular networks. These changes in brain connectivity may serve as biomarkers for pediatric PTSD.
Area of Science:
- Neuroscience
- Psychiatry
- Network Science
Background:
- Children exposed to natural disasters face risks for developing posttraumatic stress disorder (PTSD).
- Graph theory analysis of the brain's functional connectome is increasingly used for neuropsychiatric disorders.
- Limited research exists on the functional connectome's topological properties in pediatric PTSD.
Purpose of the Study:
- To investigate the topological properties of the whole-brain functional connectome in children with PTSD.
- To compare the functional connectome network characteristics between pediatric PTSD patients and trauma-exposed controls.
Main Methods:
- Recruited 28 pediatric PTSD patients and 26 trauma-exposed controls from 4,200 screened subjects post-earthquake.
- Acquired resting-state functional magnetic resonance imaging (fMRI) data.
- Constructed functional connectomes using partial correlation coefficients for 90 brain regions and applied graph theory analysis.
Main Results:
- Both groups exhibited a 'small-world' brain network topology.
- The pediatric PTSD group showed increased clustering coefficient, normalized characteristic path length, and local efficiency, indicating a shift towards regular networks.
- PTSD connectomes displayed enhanced nodal centralities in default mode and salience networks, and reduced centralities in central-executive networks.
- Left superior frontal gyrus clustering coefficient and nodal efficiency correlated with PTSD symptom severity.
Conclusions:
- Disrupted functional connectome topology is evident in pediatric PTSD.
- These topological alterations may elucidate the pathogenesis of pediatric PTSD.
- Altered brain network properties could serve as potential biomarkers for pediatric PTSD.
Abstract:
Children exposed to natural disasters are vulnerable to the development of posttraumatic stress disorder (PTSD). Recent studies of other neuropsychiatric disorders have used graph-based theoretical analysis to investigate the topological properties of the functional brain connectome. However, little is known about this connectome in pediatric PTSD. Twenty-eight pediatric PTSD patients and 26 trauma-exposed non-PTSD patients were recruited from 4,200 screened subjects after the 2008 Sichuan earthquake to undergo a resting-state functional magnetic resonance imaging scan. Functional connectivity between 90 brain regions from the automated anatomical labeling atlas was established using partial correlation coefficients, and the whole-brain functional connectome was constructed by applying a threshold to the resultant 90 * 90 partial correlation matrix. Graph theory analysis was then used to examine the group-specific topological properties of the two functional connectomes. Both the PTSD and non-PTSD control groups exhibited "small-world" brain network topology. However, the functional connectome of the PTSD group showed a significant increase in the clustering coefficient and a normalized characteristic path length and local efficiency, suggesting a shift toward regular networks. Furthermore, the PTSD connectomes showed both enhanced nodal centralities, mainly in the default mode- and salience-related regions, and reduced nodal centralities, mainly in the central-executive network regions. The clustering coefficient and nodal efficiency of the left superior frontal gyrus were positively correlated with the Clinician-Administered PTSD Scale. These disrupted topological properties of the functional connectome help to clarify the pathogenesis of pediatric PTSD and could be potential biomarkers of brain abnormalities.
