Size matters: Increased grey matter in boys with conduct problems and callous–unemotional traits

TLDR

Adult psychopathy imaging reveals limbic and prefrontal abnormalities, yet no structural brain study has examined children with conduct problems and callous‑unemotional traits. The study compared whole‑brain grey matter volumes and concentrations in boys with elevated callous‑unemotional conduct problems versus typically developing boys, focusing on four predefined regions of interest. Voxel‑based morphometry of sMRI scans from 23 CU‑conduct boys and 25 controls, with probability maps and four a priori ROIs, assessed grey‑matter volume and concentration while controlling for cognition and hyperactivity‑inattention. CU‑conduct boys showed higher grey‑matter concentration in medial orbitofrontal and anterior cingulate cortices and larger grey‑matter volume and concentration in bilateral temporal lobes, suggesting delayed cortical maturation in regions linked to decision making, morality, and empathy.

Abstract

Brain imaging studies of adults with psychopathy have identified structural and functional abnormalities in limbic and prefrontal regions that are involved in emotion recognition, decision-making, morality and empathy. Among children with conduct problems, a small subgroup presents callous-unemotional traits thought to be antecedents of psychopathy. No structural brain imaging study has examined this subgroup of children. The present study used voxel-based morphometry to compare whole brain grey matter volumes and concentrations of boys with elevated levels of callous-unemotional conduct problems and typically developing boys and explored four a priori regions of interest. sMRI scans were collected from 23 boys with elevated levels of callous-unemotional conduct problems (mean age = 11 years 8 months) and 25 typically developing boys (mean age = 11 years 6 months) selected from a community sample of children. Data were analysed using optimized voxel-based morphometry. Study-specific probability maps were created and four a priori regions of interest identified (orbitofrontal, anterior cingulate and anterior insular cortices and amygdala). Both grey matter volume and concentration were examined controlling for cognitive ability and hyperactivity-inattention symptoms. Boys with callous-unemotional conduct problems, as compared with typically developing boys, presented increased grey matter concentration in the medial orbitofrontal and anterior cingulate cortices, as well as increased grey matter volume and concentration in the temporal lobes bilaterally. These findings may indicate a delay in cortical maturation in several brain areas implicated in decision making, morality and empathy in boys with callous-unemotional conduct problems.