Fu Linyan, Wang Yue, Fang Hui, Xiao Xiang, Xiao Ting, Li Yun, Li Chunyan, Wu Qiaorong, Chu Kangkang, Xiao Chaoyong, Ke Xiaoyan
Nanjing Brain Hospital Affiliated to Nanjing Medical University, Child Mental Health Research Center, Nanjing 210029, China.
Nanjing Brain Hospital Affiliated to Nanjing Medical University, Child Mental Health Research Center, Nanjing 210029, China.
Neuroscience. 2020 Apr 15;432:137-149. doi: 10.1016/j.neuroscience.2020.02.028. Epub 2020 Feb 27.
Some previous studies have demonstrated atypical brain lateralization in autism spectrum disorder (ASD). However, most of these reports have focused on language-related asymmetries in adults, and the developmental trajectory of hemispheric asymmetries in the important phase that occurs at 2-5 years of age remains unclear. Thus, we used structural magnetic resonance imaging and diffusion tensor imaging (DTI) in a longitudinal study of grey matter (GM) asymmetries across all cortical parcellation units (PUs) and white matter (WM) lateralization across the WM skeleton using voxel-based morphometry and tract-based spatial statistics (TBSS) in 34 toddlers with ASD and a matched group of 26 toddlers with developmental delay (DD) at 2-3 years old and with follow-up at 4-5 years of age. We found the total brain volume and fractional anisotropy (FA) of WM was higher in the ASD group than in the DD group at baseline and 2 years later. The ASD and DD groups showed a rightward asymmetry in a large number of cortical PUs and in the WM skeleton at both time points. GM lateralization was associated with the social and communicative disturbances observed in ASD at baseline, while WM asymmetry was significantly related to social disturbances and repetitive behaviours seen at 4-5 years of age. In conclusion, both ASD and DD toddlers had widespread rightward asymmetry, and the patterns of lateralization were similar across the groups. GM and WM showed asynchronous development of hemispheric asymmetries at 2-5 years of age, and this lateralization was associated with ASD symptoms.
先前的一些研究已经证明自闭症谱系障碍（ASD）存在非典型的大脑偏侧化。然而，这些报告大多集中在成年人与语言相关的不对称性上，而在2至5岁这一重要阶段半球不对称性的发育轨迹仍不清楚。因此，我们在一项纵向研究中，对34名患有ASD的幼儿和一组与之匹配的26名患有发育迟缓（DD）的幼儿进行了结构磁共振成像和扩散张量成像（DTI），这些幼儿在2至3岁时进行研究，并在4至5岁时进行随访，采用基于体素的形态测量法和基于纤维束的空间统计（TBSS）来研究所有皮质分区单元（PU）的灰质（GM）不对称性以及整个白质骨架的白质（WM）偏侧化。我们发现，在基线时以及2年后，ASD组的全脑体积和WM的分数各向异性（FA）均高于DD组。在两个时间点，ASD组和DD组在大量皮质PU和WM骨架中均表现出右侧不对称。GM偏侧化与基线时ASD中观察到的社交和沟通障碍相关，而WM不对称与4至5岁时出现的社交障碍和重复行为显著相关。总之，患有ASD和DD的幼儿均存在广泛的右侧不对称，且各组间的偏侧化模式相似。在2至5岁时，GM和WM表现出半球不对称的异步发育，这种偏侧化与ASD症状相关。
