Data_Sheet_1.DOCX

The present functional magnetic resonance imaging (fMRI) study investigated influences of language contexts on inhibitory control and the underlying neural processes. Thirty Cantonese–Mandarin–English trilingual speakers, who were highly proficient in Cantonese (L1) and Mandarin (L2), and moderately proficient in English (L3), performed a picture-naming task in three dual-language contexts (L1-L2, L2-L3, and L1-L3). After each of the three naming tasks, participants performed a flanker task, measuring contextual effects on the inhibitory control system. Behavioral results showed a typical flanker effect in the L2-L3 and L1-L3 condition, but not in the L1-L2 condition, which indicates contextual facilitation on inhibitory control performance by the L1-L2 context. Whole brain analysis of the fMRI data acquired during the flanker tasks showed more neural activations in the right prefrontal cortex and subcortical areas in the L2-L3 and L1-L3 condition on one hand as compared to the L1-L2 condition on the other hand, suggesting greater involvement of the cognitive control areas when participants were performing the flanker task in L2-L3 and L1-L3 contexts. Effective connectivity analyses displayed a cortical-subcortical-cerebellar circuitry for inhibitory control in the trilinguals. However, contrary to the right-lateralized network in the L1-L2 condition, functional networks for inhibitory control in the L2-L3 and L1-L3 condition are less integrated and more left-lateralized. These findings provide a novel perspective for investigating the interaction between bilingualism (multilingualism) and inhibitory control by demonstrating instant behavioral effects and neural plasticity as a function of changes in global language contexts.

本项功能性磁共振成像（fMRI）研究探讨了语言环境对抑制控制及其潜在神经过程的影响。三十位精通粤语（L1）、普通话（L2）并具备一定英语（L3）水平的粤语-普通话-英语三语者参与了本研究。受试者在三种双语言情境（L1-L2、L2-L3和L1-L3）下执行了图片命名任务。在每个命名任务之后，参与者均完成了侧翼任务，以测量语境对抑制控制系统的影响。行为结果表明，在L2-L3和L1-L3条件下出现了典型的侧翼效应，而在L1-L2条件下则未出现，这表明L1-L2语境对抑制控制性能的促进作用。对侧翼任务期间获取的全脑fMRI数据进行整体分析显示，与L1-L2条件相比，L2-L3和L1-L3条件下右侧前额叶皮层和皮层下区域表现出更多的神经激活，这暗示了当参与者在L2-L3和L1-L3语境下执行侧翼任务时，认知控制区域的参与度更高。有效连接性分析揭示了三语者中用于抑制控制的皮质-皮层下-小脑回路。然而，与L1-L2条件下的右侧偏侧化网络相反，L2-L3和L1-L3条件下的抑制控制功能网络整合度较低，且更为左侧偏侧化。这些发现为探讨双语（多语）与抑制控制之间的相互作用提供了新的视角，通过展示全球语言环境变化所带来的即时行为效应和神经可塑性，提供了新的研究思路。