Zhao Yueye, Liu Jianyi, Ma Xue'er, Huang Zi-Gang, Zhao Jingjing
School of Psychology, Shaanxi Normal University, Xi'an, 710062, Shaanxi, China.
The Key Laboratory of Biomedical Information Engineering of Ministry of Education, Institute of Health and Rehabilitation Science, School of Life Science and Technology, Xi'an Jiaotong University, No. 28 West Xianning Road, Xi'an, 710049, Shaanxi, China; Research Center for Brain-inspired Intelligence, Xi'an Jiaotong University, No. 28 West Xianning Road, Xi'an, 710049, Shaanxi, China.
Neuroimage. 2025 Mar;308:121071. doi: 10.1016/j.neuroimage.2025.121071. Epub 2025 Feb 1.
Previous research has shown that the thalamus is crucial in reading, with its function depending largely on its connections with the cortex. However, the relationship between the lateralization of thalamocortical connections and reading has not been well-explored. This study investigates the microstructure and its lateralization differences in thalamocortical white matter fiber tracts in individuals with varying reading abilities and explores their relationship with reading skills and early reading performances. The study involved 26 Mandarin-speaking adults with a history of reading difficulties and 35 typically developing Mandarin-speaking adults. Severity of reading difficulties were accessed via the Chinese Adult Reading History Questionnaire (C-ARHQ) self-reported by participants. Reading-related abilities including reading accuracy, phonological awareness, and rapid automatized naming were assessed. Neuroimaging data, including T1-weighted and diffusion-weighted images, were collected. Thalamocortical white matter fiber tracts were reconstructed using the constrained spherical deconvolution (CSD) model and grouped into six regions based on connections with bilateral brain areas. The Neurite Orientation Dispersion and Density Imaging (NODDI) model was employed to evaluate the microstructural properties of these tracts, calculating lateralization indices for the orientation dispersion index (ODI), neurite density index (NDI), and isotropic volume fraction (VISO). Results revealed that individuals with reading difficulties had significantly lower NDI values in the left and right frontal-thalamic and occipital-thalamic fiber tracts compared to good readers. Additionally, greater rightward lateralization of frontal-thalamic white matter fiber tracts was linked to poorer early reading performance in those with reading difficulties. Our study reveals atypical thalamocortical white matter connections in adults with a history of reading difficulties, and the lateralization of these connections is influenced by severity of early reading difficulties.
先前的研究表明，丘脑在阅读中起着关键作用，其功能很大程度上取决于与皮层的连接。然而，丘脑皮质连接的偏侧化与阅读之间的关系尚未得到充分探索。本研究调查了具有不同阅读能力的个体丘脑皮质白质纤维束的微观结构及其偏侧化差异，并探讨了它们与阅读技能和早期阅读表现的关系。该研究纳入了26名有阅读困难史的成年汉语使用者和35名发育正常的成年汉语使用者。通过参与者自我报告的中国成人阅读史问卷（C-ARHQ）评估阅读困难的严重程度。评估了包括阅读准确性、语音意识和快速自动命名在内的与阅读相关的能力。收集了神经影像学数据，包括T1加权和扩散加权图像。使用约束球形反卷积（CSD）模型重建丘脑皮质白质纤维束，并根据与双侧脑区的连接将其分为六个区域。采用神经突方向离散度和密度成像（NODDI）模型评估这些纤维束的微观结构特性，计算方向离散度指数（ODI）、神经突密度指数（NDI）和各向同性体积分数（VISO）的偏侧化指数。结果显示，与阅读能力良好的个体相比，有阅读困难的个体在左、右额丘脑和枕丘脑纤维束中的NDI值显著更低。此外，额丘脑白质纤维束向右更大程度的偏侧化与有阅读困难的个体较差的早期阅读表现有关。我们的研究揭示了有阅读困难史的成年人丘脑皮质白质连接存在异常，并且这些连接的偏侧化受早期阅读困难严重程度的影响。
