School of Psychology, Deakin University, Geelong, Victoria, Australia.
Center for Neurodevelopmental and Imaging Research, Kennedy Krieger Institute, Baltimore, Maryland, USA.
Hum Brain Mapp. 2024 Oct;45(14):e70002. doi: 10.1002/hbm.70002.
Subtle motor signs are a common feature in children with attention-deficit/hyperactivity disorder (ADHD). It has long been suggested that white matter abnormalities may be involved in their presentation, though no study has directly probed this question. The aim of this study was to investigate the relationship between white matter organization and the severity of subtle motor signs in children with and without ADHD. Participants were 92 children with ADHD aged between 8 and 12 years, and 185 typically developing controls. Subtle motor signs were examined using the Physical and Neurological Examination for Soft Signs (PANESS). Children completed diffusion MRI, and fixel-based analysis was performed after preprocessing. Tracts of interest were delineated using TractSeg including the corpus callosum (CC), the bilateral corticospinal tracts (CST), superior longitudinal fasciculus, and fronto-pontine tracts (FPT). Fiber cross-section (FC) was calculated for each tract. Across all participants, lower FC in the CST was associated with higher PANESS Total score (greater motor deficits). Within the PANESS, similar effects were observed for Timed Left and Right maneuvers of the hands and feet, with lower FC of the CST, CC, and FPT associated with poorer performance. No significant group differences were observed in FC in white matter regions associated with PANESS performance. Our data are consistent with theoretical accounts implicating white matter organization in the expression of motor signs in childhood. However, rather than contributing uniquely to the increased severity of soft motor signs in those with ADHD, white matter appears to contribute to these symptoms in childhood in general.
微妙的运动迹象是注意缺陷多动障碍（ADHD）儿童的常见特征。长期以来，人们一直认为白质异常可能与他们的表现有关，但没有研究直接探讨这个问题。本研究旨在调查 ADHD 儿童和对照组儿童之间白质组织与微妙运动迹象严重程度之间的关系。参与者为 92 名 8 至 12 岁的 ADHD 儿童和 185 名对照组儿童。使用身体和神经检查软体征（PANESS）检查微妙的运动迹象。儿童完成弥散 MRI，预处理后进行固定点分析。使用 TractSeg 描绘感兴趣的束，包括胼胝体（CC）、双侧皮质脊髓束（CST）、上纵束和额桥束（FPT）。计算每个束的纤维交叉（FC）。在所有参与者中，CST 的 FC 越低，PANESS 总分（更多运动缺陷）越高。在 PANESS 中，手和脚的定时左右运动的相似效果也观察到，CST、CC 和 FPT 的 FC 越低，表现越差。在与 PANESS 表现相关的白质区域的 FC 中，未观察到组间差异。我们的数据与理论一致，即白质组织参与了儿童运动迹象的表达。然而，白质似乎并没有独特地导致 ADHD 儿童软运动迹象的严重程度增加，而是在儿童中普遍导致这些症状。
