Source-based morphometry analyses yield associations between large-scale structural brain networks and psychopathic traits in incarcerated adolescents.

Studies commonly report that youth with elevated psychopathic traits exhibit deficits within limbic and paralimbic regions, including reduced gray matter volume (GMV) in the amygdala, orbitofrontal cortex (OFC), and temporal pole. However, studies have also reported additional structural abnormalities in regions extending beyond limbic and paralimbic regions among youth with elevated psychopathic traits, including the middle frontal gyrus (MFG), inferior frontal gyrus (IFG), precuneus, inferior parietal lobule (IPL), and fusiform gyrus. This suggests youth with elevated psychopathic traits may be associated with deficits within large-scale structural networks. The current study investigated whether youth with elevated psychopathic traits were associated with such deficits through the use of source-based morphometry (SBM), a multivariate analysis of structural magnetic resonance imaging data. SBM uses Independent Component Analysis (ICA) to identify distinct sets of brain regions that form different large-scale structural networks. We investigated whether youth psychopathy scores, assessed via the Hare Psychopathy Checklist: Youth Version (PCL:YV), were associated with SBM loading coefficients among n = 413 incarcerated boys. Compared to participants scoring low on the PCL:YV, participants scoring high on the PCL:YV contributed less (i.e., exhibited reduced GMV) to large-scale structural networks containing limbic and paralimbic regions (e.g., the amygdala, insula, OFC, temporal pole, and posterior cingulate) and additional regions (e.g., the IFG, precuneus, IPL, and fusiform gyrus). Through the use of multivariate SBM analyses, the current study helps further improve our understanding of structural abnormalities among youth with elevated psychopathic traits.