Among youths with conduct disorder, those with callous-unemotional traits are at increased risk for persistent antisocial behaviour. Although callous-unemotional traits have been found to be associated with white-matter brain abnormalities, previous diffusion imaging studies were conducted in small samples, preventing examination of potential sex by callous-unemotional traits interaction effects on white matter. Here, we used tract-based spatial statistics at a whole-brain level and within regions of interest to compare the white matter correlates of callous-unemotional traits in female vs. male youths with conduct disorder, in a sample (n = 124) recruited through a multi-site protocol. A sex-specific association between callous-unemotional traits and white matter was found in the left uncinate fasciculus, where callous-unemotional traits were positively associated with axial diffusivity in males, while an opposite pattern was found in females. These findings are in line with previous studies suggesting that the uncinate fasciculus is a key tract implicated in the development of psychopathy, but also add to recent evidence showing that sexual dimorphism needs to be taken into account when examining the structural correlates of mental disorders in general, and callous-unemotional traits in conduct disorder in particular.

在有品行障碍的青少年中，那些具有冷酷无情特征的人持续反社会行为的风险增加。尽管已经发现冷酷无情的特征与脑白质异常有关，但之前的扩散成像研究是在小样本中进行的，从而阻止了通过冷酷无情的特征相互作用对白质的影响来检查潜在的性别。在这里，我们在全脑水平和感兴趣区域内使用基于区域的空间统计数据来比较样本中女性与男性青年与行为障碍的冷酷无情特征的白质相关性（n = 124）通过多站点协议招募。在左钩束中发现了冷酷无情特征与白质之间的性别特异性关联，其中冷酷无情特征与男性的轴向扩散性呈正相关，而在女性中发现了相反的模式。这些发现与先前的研究一致，表明钩状束是与精神病发展有关的关键通道，但也增加了最近的证据，表明在检查一般精神障碍的结构相关性时需要考虑性二态性，尤其是品行障碍中的冷酷无情特征。