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Abstract
Alterations of volume in brain regions of interest (ROIs) are associated with post-traumatic stress disorder (PTSD). Most of the extant neuroimaging research in PTSD has studied adults. The present study extends this research by using data from children (N=11,869, M age =9.92) from the ABCD study, a multisite longitudinal long-term study of brain development and childhood health in the U.S. Traumatic events (TEs) and PTSD symptoms were measured through the K- SADS for DSM-5. Values of brain ROIs were assessed using structural MRI measures. The unidirectional model was able to detect the small differences from site variance in sMRI mediators (subc: VS<.009, SE<.004; cort: VS<.009, SE<.004). Additive genetic factors explained 23.49% of the variance in TEs, 41.73% in subcortical and 19.94% in cortical mediators, and residual 21.01% in PTSD symptoms. Environmental factors explained most of the variance in TEs (C=.61, E=.16) and PTSD symptoms (resC=.19, resE=.21), as well as unique environmental factors in the cortical mediators (cort=.66). TEs highly influenced PTSD symptoms (.92). However, the indirect effect of TEs on PTSD symptoms through the mediation of volume in brain ROIs was small to non-influential at this age (subc=-.0003-.001, cort=-.001- .002). Several estimates of mediation effects were notably higher than most. Regularization via elastic net is implemented to train the mediation model to reduce bias and noise from overfitting, and to select the ROIs with mediation effects that explain the data with increased sparsity.
Publication Date
2020
Disciplines
Life Sciences
Is Part Of
VCU Graduate Research Posters