Department of Psychology, Box 351525, University of Washington, Seattle, WA 98195, USA; Institute for Learning and Brain Sciences, Box 357988, University of Washington, Seattle, WA 98195, USA; Department of Psychology and Human Development, 230 Appleton Place, Vanderbilt University, Nashville, TN 37203, USA.
Department of Psychology, Box 351525, University of Washington, Seattle, WA 98195, USA; Institute for Learning and Brain Sciences, Box 357988, University of Washington, Seattle, WA 98195, USA.
Brain Lang. 2019 Oct;197:104665. doi: 10.1016/j.bandl.2019.104665. Epub 2019 Aug 27.
Bilingual language control is characterized by the ability to select from amongst competing representations based on the current language in use. According to the Conditional Routing Model (CRM), this feat is underpinned by basal-ganglia signal-routing mechanisms, and may have implications for cognitive flexibility. The current experiment used dynamic causal modeling of fMRI data to compare network-level brain functioning in monolinguals and bilinguals during a task that required productive (semantic decision) and receptive (language) switches. Consistent with the CRM, results showed that: (1) both switch types drove activation in the basal ganglia, (2) bilinguals and monolinguals differed in the strength of influence of dorsolateral prefrontal cortex (DLPFC) on basal ganglia, and (3) differences in bilingual language experience were marginally related to the strength of influence of the switching drives onto basal ganglia. Additionally, a task-by-group interaction was found, suggesting that when bilinguals engaged in language-switching, their task-switching costs were reduced.
双语语言控制的特点是能够根据当前使用的语言从竞争的表现中进行选择。根据条件路由模型 (CRM)，这一壮举是由基底神经节信号路由机制支撑的，可能对认知灵活性有影响。当前的实验使用功能磁共振成像 (fMRI)数据的动态因果建模来比较双语者和单语者在需要生产性 (语义决策) 和接受性 (语言) 转换的任务中的网络级大脑功能。与 CRM 一致的结果表明：(1) 两种转换类型都驱动了基底神经节的激活，(2) 双语者和单语者在背外侧前额叶皮层 (DLPFC) 对基底神经节的影响强度上存在差异，(3) 双语语言经验的差异与转换驱动力对基底神经节的影响强度呈边缘相关。此外，还发现了一个任务-组间的交互作用，表明当双语者进行语言转换时，他们的任务转换成本降低了。
