Li Min, Izumoto Maya, Wang Yide, Kato Yoko, Iwatani Yoshiko, Hirata Ikuko, Mizuno Yoshifumi, Tachibana Masaya, Mohri Ikuko, Kagitani-Shimono Kuriko
Osaka University, Department of Child Development, United Graduate School of Child Development, Suita, Osaka, Japan.
Research Center for Child Mental Development, University of Fukui, Fukui, Japan.
Neuroimage. 2024 Aug 15;297:120731. doi: 10.1016/j.neuroimage.2024.120731. Epub 2024 Jul 13.
Comprehension and pragmatic deficits are prevalent in autism spectrum disorder (ASD) and are potentially linked to altered connectivity in the ventral language networks. However, previous magnetic resonance imaging studies have not sufficiently explored the microstructural abnormalities in the ventral fiber tracts underlying comprehension dysfunction in ASD. Additionally, the precise locations of white matter (WM) changes in the long tracts of patients with ASD remain poorly understood. In the current study, we applied the automated fiber-tract quantification (AFQ) method to investigate the fine-grained WM properties of the ventral language pathway and their relationships with comprehension and symptom manifestation in ASD. The analysis included diffusion/T1 weighted imaging data of 83 individuals with ASD and 83 age-matched typically developing (TD) controls. Case-control comparisons were performed on the diffusion metrics of the ventral tracts at both the global and point-wise levels. We also explored correlations between diffusion metrics, comprehension performance, and ASD traits, and conducted subgroup analyses based on age range to examine developmental moderating effects. Individuals with ASD exhibited remarkable hypoconnectivity in the ventral tracts, particularly in the temporal portions of the left inferior longitudinal fasciculus (ILF) and the inferior fronto-occipital fasciculus (IFOF). These WM abnormalities were associated with poor comprehension and more severe ASD symptoms. Furthermore, WM alterations in the ventral tract and their correlation with comprehension dysfunction were more prominent in younger children with ASD than in adolescents. These findings indicate that WM disruptions in the temporal portions of the left ILF/IFOF are most notable in ASD, potentially constituting the core neurological underpinnings of comprehension and communication deficits in autism. Moreover, impaired WM connectivity and comprehension ability in patients with ASD appear to improve with age.
理解和语用缺陷在自闭症谱系障碍（ASD）中很普遍，并且可能与腹侧语言网络的连接改变有关。然而，先前的磁共振成像研究尚未充分探索ASD中理解功能障碍背后腹侧纤维束的微观结构异常。此外，ASD患者长束中白质（WM）变化的精确位置仍知之甚少。在本研究中，我们应用自动纤维束定量（AFQ）方法来研究腹侧语言通路的细粒度WM特性及其与ASD中理解和症状表现的关系。分析包括83名ASD个体和83名年龄匹配的典型发育（TD）对照的扩散/T1加权成像数据。在全局和逐点水平上对腹侧束的扩散指标进行病例对照比较。我们还探讨了扩散指标、理解表现和ASD特征之间的相关性，并根据年龄范围进行亚组分析以检查发育调节效应。ASD个体在腹侧束中表现出明显的连接不足，特别是在左下纵束（ILF）和下额枕束（IFOF）的颞部。这些WM异常与理解能力差和更严重的ASD症状相关。此外，ASD幼儿腹侧束中的WM改变及其与理解功能障碍的相关性比青少年更明显。这些发现表明，左ILF/IFOF颞部的WM破坏在ASD中最为明显，可能构成自闭症理解和沟通缺陷的核心神经学基础。此外，ASD患者受损的WM连接性和理解能力似乎随着年龄的增长而改善。
