Department of Linguistics and Phonetics, Lund University, Lund, Sweden.
Department of Clinical Sciences Lund, Medical Radiation Physics, Lund University, Lund, Sweden.
Hum Brain Mapp. 2021 Oct 15;42(15):5037-5050. doi: 10.1002/hbm.25598. Epub 2021 Jul 20.
People learn new languages with varying degrees of success but what are the neuroanatomical correlates of the difference in language-learning aptitude? In this study, we set out to investigate how differences in cortical morphology and white matter microstructure correlate with aptitudes for vocabulary learning, phonetic memory, and grammatical inferencing as measured by the first-language neutral LLAMA test battery. We used ultra-high field (7T) magnetic resonance imaging to estimate the cortical thickness and surface area from sub-millimeter resolved image volumes. Further, diffusion kurtosis imaging was used to map diffusion properties related to the tissue microstructure from known language-related white matter tracts. We found a correlation between cortical surface area in the left posterior-inferior precuneus and vocabulary learning aptitude, possibly indicating a greater predisposition for storing word-figure associations. Moreover, we report negative correlations between scores for phonetic memory and axial kurtosis in left arcuate fasciculus as well as mean kurtosis, axial kurtosis, and radial kurtosis of the left superior longitudinal fasciculus III, which are tracts connecting cortical areas important for phonological working memory.
人们在学习新语言时取得的成功程度各不相同，但语言学习能力的差异在神经解剖学上有哪些关联呢？在这项研究中，我们旨在探讨皮质形态和白质微观结构的差异如何与词汇学习、语音记忆和语法推断能力相关联，这些能力是通过母语中立的 LLAMA 测试套件来衡量的。我们使用超高场（7T）磁共振成像来从亚毫米分辨率的图像体积中估计皮质厚度和表面积。此外，扩散峰度成像被用于从已知的语言相关白质束中映射与组织微观结构相关的扩散特性。我们发现左侧后下顶叶小脑中回的皮质表面积与词汇学习能力呈正相关，这可能表明其更倾向于存储单词-图形的联想。此外，我们报告了语音记忆得分与左侧弓状束的轴向峰度以及左侧 III 型上纵束的平均峰度、轴向峰度和径向峰度之间的负相关，这些束连接着对语音工作记忆很重要的皮质区域。
