语言功能偏侧化及其与利手、功能连接的关系

Language lateralization, handedness and functional connectivity

对大脑语言功能偏侧化的探索起始于早期对脑损伤病人的研究。现代脑影像学研究发现,语言功能偏侧化涉及额叶、颞叶、扣带回、梭状回和辅助运动区等脑区。语言偏侧化与利手和静息态功能连接之间的关系表现为:右利手的语言优势位于左半球,而左利手的则分布在左半球、右半球或两个半球;语言功能偏侧化与利手系数、静息态半球内功能连接之间具有正相关关系,与半球间功能连接呈负相关,并且语言功能偏侧化与静息态功能连接之间的关系在左右利手个体之间存在差异。总之,大脑语言功能偏侧化、利手和静息态功能连接三者之间存在相互影响,基于脑连接和遗传机制的研究将有望揭示出其底层的神经生理机制。

Language lateralization is one of the most obvious characteristics of brain functional lateralization. Previous neuroimaging studies identified numerous brain regions associated with language lateralization, such as the frontal and temporal lobes, the cingulate and fusiform gyrus, the supplementary motor area, and so on. This review synthesizes current published literature relevant to language lateralization, with an emphasis on handedness and functional connectivity. Our findings show that language lateralization is positively correlated with handedness and intra-hemisphere connectivity but is negatively correlated with inter-hemispheric connectivity. Moreover, the left-and right-handers exhibit different correlation profiles between language lateralization and functional connectivity. We discuss the relationship between language lateralization, handedness, and functional connectivity, and we propose areas for further research.