Khateb Asaid, Abutalebi Jubin, Michel Christoph M, Pegna Alan J, Lee-Jahnke Hannelore, Annoni Jean-Marie
Laboratory of Experimental Neuropsychology, Department of Neurology, Geneva University Hospitals, Geneva, Switzerland.
Int J Psychophysiol. 2007 Sep;65(3):201-13. doi: 10.1016/j.ijpsycho.2007.04.008. Epub 2007 Apr 29.
Language selection refers to the cognitive mechanism that allows bilinguals to communicate in one language or the other and to switch between languages depending on the listener. Previous studies suggested that various brain areas might be involved in this process. However, the question remains whether language selection is achieved through a language-specific mechanism or through a general cognitive control process. To address this question, we compared event-related potentials (ERPs) induced by language selection and task selection processes during image naming. ERPs were collected from bilingual subjects while tested in two different contexts: a monolingual task selection context (TSc) where a post-stimulus cue instructed subjects either to name the image or generate a corresponding verb in their first language (L1), and a bilingual language selection context (LSc) where the cue indicated to name the image either in the first or the second language. By comparing the ERPs induced by the same L1 naming as a function of context, we assumed that if the selection processes varied across contexts, then electric brain responses should differ rapidly after the cue presentation. Our analysis indicated that the first ERP differences accounting for the diverging processes involved appeared between approximately 220 and 300 ms after the cue. The estimation by source localisation of brain regions accounting for these differences pointed to an increased activation during LSc in the left middle frontal-precentral gyri, supramarginal and angular gyri. Our results suggest that language selection is achieved through a neural network involving areas implicated in both general cognitive processes and language processing.
语言选择是指一种认知机制，它使双语者能够根据听众的情况用一种语言或另一种语言进行交流，并在不同语言之间进行切换。先前的研究表明，这一过程可能涉及多个脑区。然而，语言选择是通过特定语言机制还是通过一般认知控制过程来实现的问题仍然存在。为了解决这个问题，我们比较了图像命名过程中语言选择和任务选择过程诱发的事件相关电位（ERP）。在两种不同情境下对双语受试者进行测试时收集ERP：一种是单语任务选择情境（TSc），刺激后提示指示受试者用其第一语言（L1）命名图像或生成相应动词；另一种是双语语言选择情境（LSc），提示指示受试者用第一语言或第二语言命名图像。通过比较相同L1命名在不同情境下诱发的ERP，我们假设，如果选择过程因情境而异，那么在提示呈现后，脑电反应应该会迅速不同。我们的分析表明，在提示后约220至300毫秒之间出现了首次反映不同过程的ERP差异。对解释这些差异的脑区进行源定位估计表明，在LSc期间，左侧额中回-中央前回、缘上回和角回的激活增加。我们的结果表明，语言选择是通过一个神经网络实现的，该网络涉及参与一般认知过程和语言处理的区域。
