Barbeau Elise B, Chai Xiaoqian J, Chen Jen-Kai, Soles Jennika, Berken Jonathan, Baum Shari, Watkins Kate E, Klein Denise
Cognitive Neuroscience Unit, Montreal Neurological Institute, McGill University, 3801 Rue University, Montreal, QC, Canada H3A 2B4; Center for Research on Brain, Language and Music (CRBLM), McGill University, 3640 rue de la Montagne, Montreal, QC, Canada H3G 2A8.
Cognitive Neuroscience Unit, Montreal Neurological Institute, McGill University, 3801 Rue University, Montreal, QC, Canada H3A 2B4.
Neuropsychologia. 2017 Apr;98:169-176. doi: 10.1016/j.neuropsychologia.2016.10.003. Epub 2016 Oct 7.
Research to date suggests that second language acquisition results in functional and structural changes in the bilingual brain, however, in what way and how quickly these changes occur remains unclear. To address these questions, we studied fourteen English-speaking monolingual adults enrolled in a 12-week intensive French language-training program in Montreal. Using functional MRI, we investigated the neural changes associated with new language acquisition. The participants were scanned before the start of the immersion program and at the end of the 12 weeks. The fMRI scan aimed to investigate the brain regions recruited in a sentence reading task both in English, their first language (L1), and in French, their second language (L2). For the L1, fMRI patterns did not change from Time 1 to Time 2, while for the L2, the brain response changed between Time 1 and Time 2 in language-related areas. Of note, for the L2, there was higher activation at Time 2 compared to Time 1 in the left inferior parietal lobule (IPL) including the supramarginal gyrus. At Time 2 this higher activation in the IPL correlated with faster L2 reading speed. Moreover, higher activation in the left IPL at Time 1 predicted improvement in L2 reading speed from Time 1 to Time 2. Our results suggest that learning-induced plasticity occurred as early as 12 weeks into immersive second-language training, and that the IPL appears to play a special role in language learning.
迄今为止的研究表明，第二语言习得会导致双语者大脑在功能和结构上发生变化，然而，这些变化以何种方式以及多快发生仍不清楚。为了解决这些问题，我们对14名以英语为母语的单语成年人进行了研究，他们参加了蒙特利尔为期12周的强化法语培训项目。我们使用功能磁共振成像（fMRI）来研究与新语言习得相关的神经变化。参与者在沉浸式课程开始前和12周结束时接受扫描。fMRI扫描旨在研究在句子阅读任务中，他们的第一语言（L1）英语和第二语言（L2）法语所激活的脑区。对于L1，fMRI模式从时间1到时间2没有变化，而对于L2，在与语言相关的区域，大脑反应在时间1和时间2之间发生了变化。值得注意的是，对于L2，在包括缘上回在内的左侧顶下小叶（IPL），时间2的激活程度高于时间1。在时间2时，IPL中这种更高的激活与更快的L2阅读速度相关。此外，时间1时左侧IPL中更高的激活预示着从时间1到时间2 L2阅读速度的提高。我们的研究结果表明，学习诱导的可塑性在沉浸式第二语言训练12周时就已出现，并且IPL似乎在语言学习中发挥着特殊作用。
